refactor(arbiter-client): rewrite errors to terrros

.claude/memory/feedback_widget_decomposition.md

@@ -1,11 +0,0 @@
----
-name: Widget decomposition and provider subscriptions
-description: Prefer splitting screens into multiple focused files/widgets; each widget subscribes to its own relevant providers
-type: feedback
----
-
-Split screens into multiple smaller widgets across multiple files. Each widget should subscribe only to the providers it needs (`ref.watch` at lowest possible level), rather than having one large screen widget that watches everything and passes data down as parameters.
-
-**Why:** Reduces unnecessary rebuilds; improves readability; each file has one clear responsibility.
-
-**How to apply:** When building a new screen, identify which sub-widgets need their own provider subscriptions and extract them into separate files (e.g., `widgets/grant_card.dart` watches enrichment providers itself, rather than the screen doing it and passing resolved strings down).

.gitattributes

@@ -1 +0,0 @@
-* text=auto eol=lf

.gitignore

@@ -3,4 +3,3 @@ scripts/__pycache__/
 .DS_Store
 .cargo/config.toml
 .vscode/
-docs/superpowers

.woodpecker/server-test.yaml

@@ -24,4 +24,4 @@ steps:
       - mise install rust 
       - mise install protoc
       - mise install cargo:cargo-nextest
-      - mise exec cargo:cargo-nextest -- cargo nextest run --no-fail-fast --all-features
+      - mise exec cargo:cargo-nextest -- cargo nextest run --no-fail-fast

AGENTS.md

@@ -6,7 +6,7 @@ This file provides guidance to Codex (Codex.ai/code) when working with code in t
 
 Arbiter is a **permissioned signing service** for cryptocurrency wallets. It consists of:
 - **`server/`** — Rust gRPC daemon that holds encrypted keys and enforces policies
-- **`operator/`** — Flutter desktop app (macOS/Windows) with a Rust backend via Rinf
+- **`useragent/`** — Flutter desktop app (macOS/Windows) with a Rust backend via Rinf
 - **`protobufs/`** — Protocol Buffer definitions shared between server and client
 
 The vault never exposes key material; it only produces signatures when requests satisfy configured policies.
@@ -28,7 +28,7 @@ Key versions: Rust 1.93.0 (with clippy), Flutter 3.38.9-stable, protoc 29.6, die
 |---|---|
 | `arbiter-proto` | Generated gRPC stubs + protobuf types; compiled from `protobufs/*.proto` via `tonic-prost-build` |
 | `arbiter-server` | Main daemon — actors, DB, EVM policy engine, gRPC service implementation |
-| `arbiter-operator` | Rust client library for the operator side of the gRPC protocol |
+| `arbiter-useragent` | Rust client library for the user agent side of the gRPC protocol |
 | `arbiter-client` | Rust client library for SDK clients |
 
 ### Common Commands
@@ -66,11 +66,11 @@ cargo insta review
 The server is actor-based using the **kameo** crate. All long-lived state lives in `GlobalActors`:
 
 - **`Bootstrapper`** — Manages the one-time bootstrap token written to `~/.arbiter/bootstrap_token` on first run.
-- **`Vault`** — Holds the encrypted root key and manages the Sealed/Unsealed vault state machine. On unseal, decrypts the root key into a `memsafe` hardened memory cell.
-- **`FlowCoordinator`** — Coordinates cross-connection flow between operators and SDK clients.
+- **`KeyHolder`** — Holds the encrypted root key and manages the Sealed/Unsealed vault state machine. On unseal, decrypts the root key into a `memsafe` hardened memory cell.
+- **`MessageRouter`** — Coordinates streaming messages between user agents and SDK clients.
 - **`EvmActor`** — Handles EVM transaction policy enforcement and signing.
 
-Per-connection actors live under `actors/operator/` and `actors/client/`, each with `auth` (challenge-response authentication) and `session` (post-auth operations) sub-modules.
+Per-connection actors live under `actors/user_agent/` and `actors/client/`, each with `auth` (challenge-response authentication) and `session` (post-auth operations) sub-modules.
 
 **Database:** SQLite via `diesel-async` + `bb8` connection pool. Schema managed by embedded Diesel migrations in `crates/arbiter-server/migrations/`. DB file lives at `~/.arbiter/arbiter.sqlite`. Tests use a temp-file DB via `db::create_test_pool()`.
 
@@ -100,41 +100,20 @@ diesel migration generate <name> --migration-dir crates/arbiter-server/migration
 diesel migration run --migration-dir crates/arbiter-server/migrations
 ```
 
-### Code Conventions
+## User Agent (Flutter + Rinf at `useragent/`)
 
-**`#[must_use]` Attribute:**
-Apply the `#[must_use]` attribute to return types of functions where the return value is critical and should not be accidentally ignored. This is commonly used for:
+The Flutter app uses [Rinf](https://rinf.cunarist.org) to call Rust code. The Rust logic lives in `useragent/native/hub/` as a separate crate that uses `arbiter-useragent` for the gRPC client.
 
-- Methods that return `bool` indicating success/failure or validation state
-- Any function where ignoring the return value indicates a logic error
-
-Do not apply `#[must_use]` redundantly to items (types or functions) that are already annotated with `#[must_use]`.
-
-Example:
-
-```rust
-#[must_use]
-pub fn verify(&self, nonce: i32, context: &[u8], signature: &Signature) -> bool {
-    // verification logic
-}
-```
-
-This forces callers to either use the return value or explicitly ignore it with `let _ = ...;`, preventing silent failures.
-
-## Operator (Flutter + Rinf at `operator/`)
-
-The Flutter app uses [Rinf](https://rinf.cunarist.org) to call Rust code. The Rust logic lives in `operator/native/hub/` as a separate crate that uses `arbiter-operator` for the gRPC client.
-
-Communication between Dart and Rust uses typed **signals** defined in `operator/native/hub/src/signals/`. After modifying signal structs, regenerate Dart bindings:
+Communication between Dart and Rust uses typed **signals** defined in `useragent/native/hub/src/signals/`. After modifying signal structs, regenerate Dart bindings:
 
 ```sh
-cd operator && rinf gen
+cd useragent && rinf gen
 ```
 
 ### Common Commands
 
 ```sh
-cd operator
+cd useragent
 
 # Run the app (macOS or Windows)
 flutter run
@@ -146,4 +125,4 @@ rinf gen
 flutter analyze
 ```
 
-The Rinf Rust entry point is `operator/native/hub/src/lib.rs`. It spawns actors defined in `operator/native/hub/src/actors/` which handle Dart↔server communication via signals.
+The Rinf Rust entry point is `useragent/native/hub/src/lib.rs`. It spawns actors defined in `useragent/native/hub/src/actors/` which handle Dart↔server communication via signals.

ARCHITECTURE.md

@@ -0,0 +1,155 @@
+# Arbiter
+
+Arbiter is a permissioned signing service for cryptocurrency wallets. It runs as a background service on the user's machine with an optional client application for vault management.
+
+**Core principle:** The vault NEVER exposes key material. It only produces signatures when a request satisfies the configured policies.
+---
+
+## 1. Peer Types
+
+Arbiter distinguishes two kinds of peers:
+
+- **User Agent** — A client application used by the owner to manage the vault (create wallets, approve SDK clients, configure policies).
+- **SDK Client** — A consumer of signing capabilities, typically an automation tool. In the future, this could include a browser-based wallet.
+
+---
+
+## 2. Authentication
+
+### 2.1 Challenge-Response
+
+All peers authenticate via public-key cryptography using a challenge-response protocol:
+
+1. The peer sends its public key and requests a challenge.
+2. The server looks up the key in its database. If found, it increments the nonce and returns a challenge (replay-attack protection).
+3. The peer signs the challenge with its private key and sends the signature back.
+4. The server verifies the signature:
+   - **Pass:** The connection is considered authenticated.
+   - **Fail:** The server closes the connection.
+
+### 2.2 User Agent Bootstrap
+
+On first run — when no User Agents are registered — the server generates a one-time bootstrap token. It is made available in two ways:
+
+- **Local setup:** Written to `~/.arbiter/bootstrap_token` for automatic discovery by a co-located User Agent.
+- **Remote setup:** Printed to the server's console output.
+
+The first User Agent must present this token alongside the standard challenge-response to complete registration.
+
+### 2.3 SDK Client Registration
+
+There is no bootstrap mechanism for SDK clients. They must be explicitly approved by an already-registered User Agent.
+
+---
+
+## 3. Server Identity
+
+The server proves its identity using TLS with a self-signed certificate. The TLS private key is generated on first run and is long-term; no rotation mechanism exists yet due to the complexity of multi-peer coordination.
+
+Peers verify the server by its **public key fingerprint**:
+
+- **User Agent (local):** Receives the fingerprint automatically through the bootstrap token.
+- **User Agent (remote) / SDK Client:** Must receive the fingerprint out-of-band.
+
+> A streamlined setup mechanism using a single connection string is planned but not yet implemented.
+
+---
+
+## 4. Key Management
+
+### 4.1 Key Hierarchy
+
+There are three layers of keys:
+
+| Key | Encrypts | Encrypted by |
+|---|---|---|
+| **User key** (password) | Root key | — (derived from user input) |
+| **Root key** | Wallet keys | User key |
+| **Wallet keys** | — (used for signing) | Root key |
+
+This layered design enables:
+
+- **Password rotation** without re-encrypting every wallet key (only the root key is re-encrypted).
+- **Root key rotation** without requiring the user to change their password.
+
+### 4.2 Encryption at Rest
+
+The database stores everything in encrypted form using symmetric AEAD. The encryption scheme is versioned to support transparent migration — when the vault unseals, Arbiter automatically re-encrypts any entries that are behind the current scheme version. See [IMPLEMENTATION.md](IMPLEMENTATION.md) for the specific scheme and versioning mechanism.
+
+---
+
+## 5. Vault Lifecycle
+
+### 5.1 Sealed State
+
+On boot, the root key is encrypted and the server cannot perform any signing operations. This state is called **Sealed**.
+
+### 5.2 Unseal Flow
+
+To transition to the **Unsealed** state, a User Agent must provide the password:
+
+1. The User Agent initiates an unseal request.
+2. The server generates a one-time key pair and returns the public key.
+3. The User Agent encrypts the user's password with this one-time public key and sends the ciphertext to the server.
+4. The server decrypts and verifies the password:
+   - **Success:** The root key is decrypted and placed into a hardened memory cell. The server transitions to `Unsealed`. Any entries pending encryption scheme migration are re-encrypted.
+   - **Failure:** The server returns an error indicating the password is incorrect.
+
+### 5.3 Memory Protection
+
+Once unsealed, the root key must be protected in memory against:
+
+- Memory dumps
+- Page swaps to disk
+- Hibernation files
+
+See [IMPLEMENTATION.md](IMPLEMENTATION.md) for the current and planned memory protection approaches.
+
+---
+
+## 6. Permission Engine
+
+### 6.1 Fundamental Rules
+
+- SDK clients have **no access by default**.
+- Access is granted **explicitly** by a User Agent.
+- Grants are scoped to **specific wallets** and governed by **policies**.
+
+Each blockchain requires its own policy system due to differences in static transaction analysis. Currently, only EVM is supported; Solana support is planned.
+
+Arbiter is also responsible for ensuring that **transaction nonces are never reused**.
+
+### 6.2 EVM Policies
+
+Every EVM grant is scoped to a specific **wallet** and **chain ID**.
+
+#### 6.2.1 Transaction Sub-Grants
+
+Arbiter maintains an ever-expanding database of known contracts and their ABIs. Based on contract knowledge, transaction requests fall into three categories:
+
+**1. Known contract (ABI available)**
+
+The transaction can be decoded and presented with semantic meaning. For example: *"Client X wants to transfer Y USDT to address Z."*
+
+Available restrictions:
+- Volume limits (e.g., "no more than 10,000 tokens ever")
+- Rate limits (e.g., "no more than 100 tokens per hour")
+
+**2. Unknown contract (no ABI)**
+
+The transaction cannot be decoded, so its effects are opaque — it could do anything, including draining all tokens. The user is warned, and if approved, access is granted to all interactions with the contract (matched by the `to` field).
+
+Available restrictions:
+- Transaction count limits (e.g., "no more than 100 transactions ever")
+- Rate limits (e.g., "no more than 5 transactions per hour")
+
+**3. Plain ether transfer (no calldata)**
+
+These transactions have no `calldata` and therefore cannot interact with contracts. They can be subject to the same volume and rate restrictions as above.
+
+#### 6.2.2 Global Limits
+
+In addition to sub-grant-specific restrictions, the following limits can be applied across all grant types:
+
+- **Gas limit** — Maximum gas per transaction.
+- **Time-window restrictions** — e.g., signing allowed only 08:00–20:00 on Mondays and Thursdays.

CLAUDE.md

@@ -1 +1,128 @@
-Refer to @AGENTS.md for instructions.
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+Arbiter is a **permissioned signing service** for cryptocurrency wallets. It consists of:
+- **`server/`** — Rust gRPC daemon that holds encrypted keys and enforces policies
+- **`useragent/`** — Flutter desktop app (macOS/Windows) with a Rust backend via Rinf
+- **`protobufs/`** — Protocol Buffer definitions shared between server and client
+
+The vault never exposes key material; it only produces signatures when requests satisfy configured policies.
+
+## Toolchain Setup
+
+Tools are managed via [mise](https://mise.jdx.dev/). Install all required tools:
+```sh
+mise install
+```
+
+Key versions: Rust 1.93.0 (with clippy), Flutter 3.38.9-stable, protoc 29.6, diesel_cli 2.3.6 (sqlite).
+
+## Server (Rust workspace at `server/`)
+
+### Crates
+
+| Crate | Purpose |
+|---|---|
+| `arbiter-proto` | Generated gRPC stubs + protobuf types; compiled from `protobufs/*.proto` via `tonic-prost-build` |
+| `arbiter-server` | Main daemon — actors, DB, EVM policy engine, gRPC service implementation |
+| `arbiter-useragent` | Rust client library for the user agent side of the gRPC protocol |
+| `arbiter-client` | Rust client library for SDK clients |
+
+### Common Commands
+
+```sh
+cd server
+
+# Build
+cargo build
+
+# Run the server daemon
+cargo run -p arbiter-server
+
+# Run all tests (preferred over cargo test)
+cargo nextest run
+
+# Run a single test
+cargo nextest run <test_name>
+
+# Lint
+cargo clippy
+
+# Security audit
+cargo audit
+
+# Check unused dependencies
+cargo shear
+
+# Run snapshot tests and update snapshots
+cargo insta review
+```
+
+### Architecture
+
+The server is actor-based using the **kameo** crate. All long-lived state lives in `GlobalActors`:
+
+- **`Bootstrapper`** — Manages the one-time bootstrap token written to `~/.arbiter/bootstrap_token` on first run.
+- **`KeyHolder`** — Holds the encrypted root key and manages the Sealed/Unsealed vault state machine. On unseal, decrypts the root key into a `memsafe` hardened memory cell.
+- **`MessageRouter`** — Coordinates streaming messages between user agents and SDK clients.
+- **`EvmActor`** — Handles EVM transaction policy enforcement and signing.
+
+Per-connection actors live under `actors/user_agent/` and `actors/client/`, each with `auth` (challenge-response authentication) and `session` (post-auth operations) sub-modules.
+
+**Database:** SQLite via `diesel-async` + `bb8` connection pool. Schema managed by embedded Diesel migrations in `crates/arbiter-server/migrations/`. DB file lives at `~/.arbiter/arbiter.sqlite`. Tests use a temp-file DB via `db::create_test_pool()`.
+
+**Cryptography:**
+- Authentication: ed25519 (challenge-response, nonce-tracked per peer)
+- Encryption at rest: XChaCha20-Poly1305 (versioned via `scheme` field for transparent migration on unseal)
+- Password KDF: Argon2
+- Unseal transport: X25519 ephemeral key exchange
+- TLS: self-signed certificate (aws-lc-rs backend), fingerprint distributed via `ArbiterUrl`
+
+**Protocol:** gRPC with Protocol Buffers. The `ArbiterUrl` type encodes host, port, CA cert, and bootstrap token into a single shareable string (printed to console on first run).
+
+### Proto Regeneration
+
+When `.proto` files in `protobufs/` change, rebuild to regenerate:
+```sh
+cd server && cargo build -p arbiter-proto
+```
+
+### Database Migrations
+
+```sh
+# Create a new migration
+diesel migration generate <name> --migration-dir crates/arbiter-server/migrations
+
+# Run migrations manually (server also runs them on startup)
+diesel migration run --migration-dir crates/arbiter-server/migrations
+```
+
+## User Agent (Flutter + Rinf at `useragent/`)
+
+The Flutter app uses [Rinf](https://rinf.cunarist.org) to call Rust code. The Rust logic lives in `useragent/native/hub/` as a separate crate that uses `arbiter-useragent` for the gRPC client.
+
+Communication between Dart and Rust uses typed **signals** defined in `useragent/native/hub/src/signals/`. After modifying signal structs, regenerate Dart bindings:
+
+```sh
+cd useragent && rinf gen
+```
+
+### Common Commands
+
+```sh
+cd useragent
+
+# Run the app (macOS or Windows)
+flutter run
+
+# Regenerate Rust↔Dart signal bindings
+rinf gen
+
+# Analyze Dart code
+flutter analyze
+```
+
+The Rinf Rust entry point is `useragent/native/hub/src/lib.rs`. It spawns actors defined in `useragent/native/hub/src/actors/` which handle Dart↔server communication via signals.

IMPLEMENTATION.md

@@ -8,10 +8,10 @@ This document covers concrete technology choices and dependencies. For the archi
 
 ### Authentication Result Semantics
 
-Authentication no longer uses an implicit success-only response shape. Both `client` and `operator` return explicit auth status enums over the wire.
+Authentication no longer uses an implicit success-only response shape. Both `client` and `user-agent` return explicit auth status enums over the wire.
 
-- **Client:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `APPROVAL_DENIED`, `NO_OPERATORS_ONLINE`, or `INTERNAL`
-- **Operator:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `BOOTSTRAP_REQUIRED`, `TOKEN_INVALID`, or `INTERNAL`
+- **Client:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `APPROVAL_DENIED`, `NO_USER_AGENTS_ONLINE`, or `INTERNAL`
+- **User-agent:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `BOOTSTRAP_REQUIRED`, `TOKEN_INVALID`, or `INTERNAL`
 
 This makes transport-level failures and actor/domain-level auth failures distinct:
 
@@ -22,50 +22,52 @@ Clients are expected to handle these status codes directly and present the concr
 
 ### New Client Approval
 
-When a client whose public key is not yet in the database connects, all connected operators are asked to approve the connection. The first operator to respond determines the outcome; remaining requests are cancelled via a watch channel.
+When a client whose public key is not yet in the database connects, all connected user agents are asked to approve the connection. The first agent to respond determines the outcome; remaining requests are cancelled via a watch channel.
 
 ```mermaid
 flowchart TD
     A([Client connects]) --> B[Receive AuthChallengeRequest]
     B --> C{pubkey in DB?}
 
-    C -- yes --> G[Generate AuthChallenge]
+    C -- yes --> D[Read nonce\nIncrement nonce in DB]
+    D --> G
 
-    C -- no --> E[Ask all Operators:\nClientConnectionRequest]
+    C -- no --> E[Ask all UserAgents:\nClientConnectionRequest]
     E --> F{First response}
     F -- denied --> Z([Reject connection])
-    F -- approved --> F2[Cancel remaining\nOperator requests]
-    F2 --> F3[INSERT client]
-    F3 --> G
+    F -- approved --> F2[Cancel remaining\nUserAgent requests]
+    F2 --> F3[INSERT client\nnonce = 1]
+    F3 --> G[Send AuthChallenge\nwith nonce]
 
-    G --> H[Send AuthChallenge\ntimestamp + random bytes]
-    H --> I[Receive AuthChallengeSolution]
-    I --> K{Signature valid?}
-    K -- no --> Z
-    K -- yes --> J([Session started])
+    G --> H[Receive AuthChallengeSolution]
+    H --> I{Signature valid?}
+    I -- no --> Z
+    I -- yes --> J([Session started])
 ```
 
-Auth challenges are generated from fresh random bytes plus a nanosecond timestamp. The server keeps the issued challenge only in the in-flight authentication state for that connection, then verifies the signature against the same canonical challenge payload.
+### Known Issue: Concurrent Registration Race (TOCTOU)
 
-The authentication schema stores peer identity, not replay counters:
+Two connections presenting the same previously-unknown public key can race through the approval flow simultaneously:
 
-- `program_client` stores the SDK client's public key, metadata binding, and timestamps.
-- `operator_client` stores the Operator public key and timestamps.
-- Neither table stores an authentication nonce, and challenge generation does not update either table.
+1. Both check the DB → neither is registered.
+2. Both request approval from user agents → both receive approval.
+3. Both `INSERT` the client record → the second insert silently overwrites the first, resetting the nonce.
+
+This means the first connection's nonce is invalidated by the second, causing its challenge verification to fail. A fix requires either serialising new-client registration (e.g. an in-memory lock keyed on pubkey) or replacing the separate check + insert with an `INSERT OR IGNORE` / upsert guarded by a unique constraint on `public_key`.
+
+### Nonce Semantics
+
+The `program_client.nonce` column stores the **next usable nonce** — i.e. it is always one ahead of the nonce last issued in a challenge.
+
+- **New client:** inserted with `nonce = 1`; the first challenge is issued with `nonce = 0`.
+- **Existing client:** the current DB value is read and used as the challenge nonce, then immediately incremented within the same exclusive transaction, preventing replay.
 
 ---
 
 ## Cryptography
 
 ### Authentication
-- **Client protocol:** ML-DSA
-
-### User-Agent Authentication
-
-Operator authentication supports multiple signature schemes because platform-provided "hardware-bound" keys do not expose a uniform algorithm across operating systems and hardware.
-
-- **Supported schemes:** ML-DSA
-- **Why:** Secure Enclave (MacOS) support them natively, on other platforms we could emulate while they roll-out
+- **Signature scheme:** ed25519
 
 ### Encryption at Rest
 - **Scheme:** Symmetric AEAD — currently **XChaCha20-Poly1305**
@@ -86,7 +88,7 @@ Operator authentication supports multiple signature schemes because platform-pro
 
 ### Request Multiplexing
 
-Both `client` and `operator` connections support multiple in-flight requests over one gRPC bidi stream.
+Both `client` and `user-agent` connections support multiple in-flight requests over one gRPC bidi stream.
 
 - Every request carries a monotonically increasing request ID
 - Every normal response echoes the request ID it corresponds to
@@ -115,52 +117,6 @@ The central abstraction is the `Policy` trait. Each implementation handles one s
 4. **Evaluate** — `Policy::evaluate` checks the decoded meaning against the grant's policy-specific constraints and returns any violations.
 5. **Record** — If `RunKind::Execution` and there are no violations, the engine writes to `evm_transaction_log` and calls `Policy::record_transaction` for any policy-specific logging (e.g., token transfer volume).
 
-The detailed branch structure is shown below:
-
-```mermaid
-flowchart TD
-    A[SDK Client sends sign transaction request] --> B[Server resolves wallet]
-    B --> C{Wallet exists?}
-
-    C -- No --> Z1[Return wallet not found error]
-    C -- Yes --> D[Check SDK client wallet visibility]
-
-    D --> E{Wallet visible to SDK client?}
-    E -- No --> F[Start wallet visibility voting flow]
-    F --> G{Vote approved?}
-    G -- No --> Z2[Return wallet access denied error]
-    G -- Yes --> H[Persist wallet visibility]
-    E -- Yes --> I[Classify transaction meaning]
-    H --> I
-
-    I --> J{Meaning supported?}
-    J -- No --> Z3[Return unsupported transaction error]
-    J -- Yes --> K[Find matching grant]
-
-    K --> L{Grant exists?}
-    L -- Yes --> M[Check grant limits]
-    L -- No --> N[Start execution or grant voting flow]
-
-    N --> O{Operator decision}
-    O -- Reject --> Z4[Return no matching grant error]
-    O -- Allow once --> M
-    O -- Create grant --> P[Create grant with user-selected limits]
-    P --> Q[Persist grant]
-    Q --> M
-
-    M --> R{Limits exceeded?}
-    R -- Yes --> Z5[Return evaluation error]
-    R -- No --> S[Record transaction in logs]
-    S --> T[Produce signature]
-    T --> U[Return signature to SDK client]
-
-    note1[Limit checks include volume, count, and gas constraints.]
-    note2[Grant lookup depends on classified meaning, such as ether transfer or token transfer.]
-
-    K -. uses .-> note2
-    M -. checks .-> note1
-```
-
 ### Policy Trait
 
 | Method | Purpose |
@@ -192,7 +148,7 @@ flowchart TD
 Every grant has two layers:
 
 - **Shared (`evm_basic_grant`)** — wallet, chain, validity period, gas fee caps, transaction count rate limit. One row per grant regardless of type.
-- **Specific** — policy-owned tables (`evm_ether_transfer_grant`, `evm_token_transfer_grant`) holding type-specific configuration.
+- **Specific** — policy-owned tables (`evm_ether_transfer_grant`, `evm_token_transfer_grant`, etc.) holding type-specific configuration.
 
 `find_all_grants` uses a `#[diesel::auto_type]` base join between the specific and shared tables, then batch-loads related rows (targets, volume limits) in two additional queries to avoid N+1.
 
@@ -215,6 +171,7 @@ These are checked centrally in `check_shared_constraints` before policy evaluati
 - **Only EIP-1559 transactions are supported.** Legacy and EIP-2930 types are rejected outright.
 - **No opaque-calldata (unknown contract) grant type.** The architecture describes a category for unrecognised contracts, but no policy implements it yet. Any transaction that is not a plain ETH transfer or a known ERC-20 transfer is unconditionally rejected.
 - **Token registry is static.** Tokens are recognised only if they appear in the hard-coded `arbiter_tokens_registry` crate. There is no mechanism to register additional contracts at runtime.
+- **Nonce management is not implemented.** The architecture lists nonce deduplication as a core responsibility, but no nonce tracking or enforcement exists yet.
 
 ---
 
@@ -222,5 +179,5 @@ These are checked centrally in `check_shared_constraints` before policy evaluati
 
 The unsealed root key must be held in a hardened memory cell resistant to dumps, page swaps, and hibernation.
 
-- **Current:** A dedicated memory-protection abstraction is in place, with `memsafe` used behind that abstraction today
-- **Planned:** Additional backends can be introduced behind the same abstraction, including a custom implementation based on `mlock` (Unix) and `VirtualProtect` (Windows)
+- **Current:** Using the `memsafe` crate as an interim solution
+- **Planned:** Custom implementation based on `mlock` (Unix) and `VirtualProtect` (Windows)

README.md

@@ -4,7 +4,7 @@
 ## Security warning
 Arbiter can't meaningfully protect against host compromise. Potential attack flow:
 - Attacker steals TLS keys from database
-- Pretends to be server; just accepts operator challenge solutions
+- Pretends to be server; just accepts user agent challenge solutions
 - Pretend to be in sealed state and performing DH with client
 - Steals user password and derives seal key
 

app/.dart_tool/extension_discovery/README.md

@@ -0,0 +1,31 @@
+Extension Discovery Cache
+=========================
+
+This folder is used by `package:extension_discovery` to cache lists of
+packages that contains extensions for other packages.
+
+DO NOT USE THIS FOLDER
+----------------------
+
+ * Do not read (or rely) the contents of this folder.
+ * Do write to this folder.
+
+If you're interested in the lists of extensions stored in this folder use the
+API offered by package `extension_discovery` to get this information.
+
+If this package doesn't work for your use-case, then don't try to read the
+contents of this folder. It may change, and will not remain stable.
+
+Use package `extension_discovery`
+---------------------------------
+
+If you want to access information from this folder.
+
+Feel free to delete this folder
+-------------------------------
+
+Files in this folder act as a cache, and the cache is discarded if the files
+are older than the modification time of `.dart_tool/package_config.json`.
+
+Hence, it should never be necessary to clear this cache manually, if you find a
+need to do please file a bug.

app/.dart_tool/extension_discovery/vs_code.json

@@ -0,0 +1 @@
+{"version":2,"entries":[{"package":"app","rootUri":"../","packageUri":"lib/"}]}

app/.dart_tool/package_config.json

@@ -0,0 +1,178 @@
+{
+  "configVersion": 2,
+  "packages": [
+    {
+      "name": "async",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/async-2.13.0",
+      "packageUri": "lib/",
+      "languageVersion": "3.4"
+    },
+    {
+      "name": "boolean_selector",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/boolean_selector-2.1.2",
+      "packageUri": "lib/",
+      "languageVersion": "3.1"
+    },
+    {
+      "name": "characters",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/characters-1.4.0",
+      "packageUri": "lib/",
+      "languageVersion": "3.4"
+    },
+    {
+      "name": "clock",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/clock-1.1.2",
+      "packageUri": "lib/",
+      "languageVersion": "3.4"
+    },
+    {
+      "name": "collection",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/collection-1.19.1",
+      "packageUri": "lib/",
+      "languageVersion": "3.4"
+    },
+    {
+      "name": "cupertino_icons",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/cupertino_icons-1.0.8",
+      "packageUri": "lib/",
+      "languageVersion": "3.1"
+    },
+    {
+      "name": "fake_async",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/fake_async-1.3.3",
+      "packageUri": "lib/",
+      "languageVersion": "3.3"
+    },
+    {
+      "name": "flutter",
+      "rootUri": "file:///Users/kaska/.local/share/mise/installs/flutter/3.38.9-stable/packages/flutter",
+      "packageUri": "lib/",
+      "languageVersion": "3.8"
+    },
+    {
+      "name": "flutter_lints",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/flutter_lints-6.0.0",
+      "packageUri": "lib/",
+      "languageVersion": "3.8"
+    },
+    {
+      "name": "flutter_test",
+      "rootUri": "file:///Users/kaska/.local/share/mise/installs/flutter/3.38.9-stable/packages/flutter_test",
+      "packageUri": "lib/",
+      "languageVersion": "3.8"
+    },
+    {
+      "name": "leak_tracker",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/leak_tracker-11.0.2",
+      "packageUri": "lib/",
+      "languageVersion": "3.2"
+    },
+    {
+      "name": "leak_tracker_flutter_testing",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/leak_tracker_flutter_testing-3.0.10",
+      "packageUri": "lib/",
+      "languageVersion": "3.2"
+    },
+    {
+      "name": "leak_tracker_testing",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/leak_tracker_testing-3.0.2",
+      "packageUri": "lib/",
+      "languageVersion": "3.2"
+    },
+    {
+      "name": "lints",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/lints-6.1.0",
+      "packageUri": "lib/",
+      "languageVersion": "3.8"
+    },
+    {
+      "name": "matcher",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/matcher-0.12.17",
+      "packageUri": "lib/",
+      "languageVersion": "3.4"
+    },
+    {
+      "name": "material_color_utilities",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/material_color_utilities-0.11.1",
+      "packageUri": "lib/",
+      "languageVersion": "2.17"
+    },
+    {
+      "name": "meta",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/meta-1.17.0",
+      "packageUri": "lib/",
+      "languageVersion": "3.5"
+    },
+    {
+      "name": "path",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/path-1.9.1",
+      "packageUri": "lib/",
+      "languageVersion": "3.4"
+    },
+    {
+      "name": "sky_engine",
+      "rootUri": "file:///Users/kaska/.local/share/mise/installs/flutter/3.38.9-stable/bin/cache/pkg/sky_engine",
+      "packageUri": "lib/",
+      "languageVersion": "3.8"
+    },
+    {
+      "name": "source_span",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/source_span-1.10.2",
+      "packageUri": "lib/",
+      "languageVersion": "3.1"
+    },
+    {
+      "name": "stack_trace",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/stack_trace-1.12.1",
+      "packageUri": "lib/",
+      "languageVersion": "3.4"
+    },
+    {
+      "name": "stream_channel",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/stream_channel-2.1.4",
+      "packageUri": "lib/",
+      "languageVersion": "3.3"
+    },
+    {
+      "name": "string_scanner",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/string_scanner-1.4.1",
+      "packageUri": "lib/",
+      "languageVersion": "3.1"
+    },
+    {
+      "name": "term_glyph",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/term_glyph-1.2.2",
+      "packageUri": "lib/",
+      "languageVersion": "3.1"
+    },
+    {
+      "name": "test_api",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/test_api-0.7.7",
+      "packageUri": "lib/",
+      "languageVersion": "3.5"
+    },
+    {
+      "name": "vector_math",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/vector_math-2.2.0",
+      "packageUri": "lib/",
+      "languageVersion": "3.1"
+    },
+    {
+      "name": "vm_service",
+      "rootUri": "file:///Users/kaska/.pub-cache/hosted/pub.dev/vm_service-15.0.2",
+      "packageUri": "lib/",
+      "languageVersion": "3.5"
+    },
+    {
+      "name": "app",
+      "rootUri": "../",
+      "packageUri": "lib/",
+      "languageVersion": "3.10"
+    }
+  ],
+  "generator": "pub",
+  "generatorVersion": "3.10.8",
+  "flutterRoot": "file:///Users/kaska/.local/share/mise/installs/flutter/3.38.9-stable",
+  "flutterVersion": "3.38.9",
+  "pubCache": "file:///Users/kaska/.pub-cache"
+}

app/.dart_tool/package_graph.json

@@ -0,0 +1,230 @@
+{
+  "roots": [
+    "app"
+  ],
+  "packages": [
+    {
+      "name": "app",
+      "version": "1.0.0+1",
+      "dependencies": [
+        "cupertino_icons",
+        "flutter"
+      ],
+      "devDependencies": [
+        "flutter_lints",
+        "flutter_test"
+      ]
+    },
+    {
+      "name": "flutter_lints",
+      "version": "6.0.0",
+      "dependencies": [
+        "lints"
+      ]
+    },
+    {
+      "name": "flutter_test",
+      "version": "0.0.0",
+      "dependencies": [
+        "clock",
+        "collection",
+        "fake_async",
+        "flutter",
+        "leak_tracker_flutter_testing",
+        "matcher",
+        "meta",
+        "path",
+        "stack_trace",
+        "stream_channel",
+        "test_api",
+        "vector_math"
+      ]
+    },
+    {
+      "name": "cupertino_icons",
+      "version": "1.0.8",
+      "dependencies": []
+    },
+    {
+      "name": "flutter",
+      "version": "0.0.0",
+      "dependencies": [
+        "characters",
+        "collection",
+        "material_color_utilities",
+        "meta",
+        "sky_engine",
+        "vector_math"
+      ]
+    },
+    {
+      "name": "lints",
+      "version": "6.1.0",
+      "dependencies": []
+    },
+    {
+      "name": "stream_channel",
+      "version": "2.1.4",
+      "dependencies": [
+        "async"
+      ]
+    },
+    {
+      "name": "meta",
+      "version": "1.17.0",
+      "dependencies": []
+    },
+    {
+      "name": "collection",
+      "version": "1.19.1",
+      "dependencies": []
+    },
+    {
+      "name": "leak_tracker_flutter_testing",
+      "version": "3.0.10",
+      "dependencies": [
+        "flutter",
+        "leak_tracker",
+        "leak_tracker_testing",
+        "matcher",
+        "meta"
+      ]
+    },
+    {
+      "name": "vector_math",
+      "version": "2.2.0",
+      "dependencies": []
+    },
+    {
+      "name": "stack_trace",
+      "version": "1.12.1",
+      "dependencies": [
+        "path"
+      ]
+    },
+    {
+      "name": "clock",
+      "version": "1.1.2",
+      "dependencies": []
+    },
+    {
+      "name": "fake_async",
+      "version": "1.3.3",
+      "dependencies": [
+        "clock",
+        "collection"
+      ]
+    },
+    {
+      "name": "path",
+      "version": "1.9.1",
+      "dependencies": []
+    },
+    {
+      "name": "matcher",
+      "version": "0.12.17",
+      "dependencies": [
+        "async",
+        "meta",
+        "stack_trace",
+        "term_glyph",
+        "test_api"
+      ]
+    },
+    {
+      "name": "test_api",
+      "version": "0.7.7",
+      "dependencies": [
+        "async",
+        "boolean_selector",
+        "collection",
+        "meta",
+        "source_span",
+        "stack_trace",
+        "stream_channel",
+        "string_scanner",
+        "term_glyph"
+      ]
+    },
+    {
+      "name": "sky_engine",
+      "version": "0.0.0",
+      "dependencies": []
+    },
+    {
+      "name": "material_color_utilities",
+      "version": "0.11.1",
+      "dependencies": [
+        "collection"
+      ]
+    },
+    {
+      "name": "characters",
+      "version": "1.4.0",
+      "dependencies": []
+    },
+    {
+      "name": "async",
+      "version": "2.13.0",
+      "dependencies": [
+        "collection",
+        "meta"
+      ]
+    },
+    {
+      "name": "leak_tracker_testing",
+      "version": "3.0.2",
+      "dependencies": [
+        "leak_tracker",
+        "matcher",
+        "meta"
+      ]
+    },
+    {
+      "name": "leak_tracker",
+      "version": "11.0.2",
+      "dependencies": [
+        "clock",
+        "collection",
+        "meta",
+        "path",
+        "vm_service"
+      ]
+    },
+    {
+      "name": "term_glyph",
+      "version": "1.2.2",
+      "dependencies": []
+    },
+    {
+      "name": "string_scanner",
+      "version": "1.4.1",
+      "dependencies": [
+        "source_span"
+      ]
+    },
+    {
+      "name": "source_span",
+      "version": "1.10.2",
+      "dependencies": [
+        "collection",
+        "path",
+        "term_glyph"
+      ]
+    },
+    {
+      "name": "boolean_selector",
+      "version": "2.1.2",
+      "dependencies": [
+        "source_span",
+        "string_scanner"
+      ]
+    },
+    {
+      "name": "vm_service",
+      "version": "15.0.2",
+      "dependencies": []
+    }
+  ],
+  "configVersion": 1
+}

app/.dart_tool/version

@@ -0,0 +1 @@
+3.38.9

docs/ARCHITECTURE.md

@@ -1,334 +0,0 @@
-# Arbiter
-
-Arbiter is a permissioned signing service for cryptocurrency wallets. It runs as a background service on the user's machine with an optional client application for vault management.
-
-**Core principle:** The vault NEVER exposes key material. It only produces signatures when a request satisfies the configured policies.
----
-
-## 1. Peer Types
-
-Arbiter distinguishes two kinds of peers:
-
-- **Operator** — A client application used by the owner to manage the vault (create wallets, approve SDK clients, configure policies).
-- **SDK Client** — A consumer of signing capabilities, typically an automation tool. In the future, this could include a browser-based wallet.
-- **Recovery Operator** — A dormant recovery participant with narrowly scoped authority used only for custody recovery and operator replacement.
-
----
-
-## 2. Authentication
-
-### 2.1 Challenge-Response
-
-All peers authenticate via public-key cryptography using a challenge-response protocol:
-
-1. The peer sends its public key and requests a challenge.
-2. The server looks up the key in its database. If found, it generates a fresh challenge from random bytes plus the current timestamp.
-3. The peer signs the canonical challenge payload with its private key and sends the signature back.
-4. The server verifies the signature:
-   - **Pass:** The connection is considered authenticated.
-   - **Fail:** The server closes the connection.
-
-Authentication challenges are per-connection, ephemeral values. They are not persisted in the peer tables, and peer records store no challenge state.
-
-### 2.2 Operator Bootstrap
-
-On first run — when no Operators are registered — the server generates a one-time bootstrap token. It is made available in two ways:
-
-- **Local setup:** Written to `~/.arbiter/bootstrap_token` for automatic discovery by a co-located Operator.
-- **Remote setup:** Printed to the server's console output.
-
-The first Operator must present this token alongside the standard challenge-response to complete registration.
-
-### 2.3 SDK Client Registration
-
-There is no bootstrap mechanism for SDK clients. They must be explicitly approved by an already-registered Operator.
-
----
-
-## 3. Multi-Operator Governance
-
-When more than one Operator is registered, the vault is treated as having multiple operators. In that mode, sensitive actions are governed by voting rather than by a single operator decision.
-
-### 3.1 Voting Rules
-
-Voting is based on the total number of registered operators:
-
-- **1 operator:** no vote is needed; the single operator decides directly.
-- **2 operators:** full consensus is required; both operators must approve.
-- **3 or more operators:** quorum is `floor(N / 2) + 1`.
-
-For a decision to count, the operator's approval or rejection must be signed by that operator's associated key. Unsigned votes, or votes that fail signature verification, are ignored.
-
-Examples:
-
-- **3 operators:** 2 approvals required
-- **4 operators:** 3 approvals required
-
-### 3.2 Actions Requiring a Vote
-
-In multi-operator mode, a successful vote is required for:
-
-- approving new SDK clients
-- granting an SDK client visibility to a wallet
-- approving a one-off transaction
-- approving creation of a persistent grant
-- approving operator replacement
-- approving server updates
-- updating Shamir secret-sharing parameters
-
-### 3.3 Special Rule for Key Rotation
-
-Key rotation always requires full quorum, regardless of the normal voting threshold.
-
-This is stricter than ordinary governance actions because rotating the root key requires every operator to participate in coordinated share refresh/update steps. The root key itself is not redistributed directly, but each operator's share material must be changed consistently.
-
-### 3.4 Root Key Custody
-
-When the vault has multiple operators, the vault root key is protected using Shamir secret sharing.
-
-The vault root key is encrypted in a way that requires reconstruction from user-held shares rather than from a single shared password.
-
-For ordinary operators, the Shamir threshold matches the ordinary governance quorum. For example:
-
-- **2 operators:** `2-of-2`
-- **3 operators:** `2-of-3`
-- **4 operators:** `3-of-4`
-
-In practice, the Shamir share set also includes Recovery Operator shares. This means the effective Shamir parameters are computed over the combined share pool while keeping the same threshold. For example:
-
-- **3 ordinary operators + 2 recovery shares:** `2-of-5`
-
-This ensures that the normal custody threshold follows the ordinary operator quorum, while still allowing dormant recovery shares to exist for break-glass recovery flows.
-
-### 3.5 Recovery Operators
-
-Recovery Operators are a separate peer type from ordinary vault operators.
-
-Their role is intentionally narrow. They can only:
-
-- participate in unsealing the vault
-- vote for operator replacement
-
-Recovery Operators do not participate in routine governance such as approving SDK clients, granting wallet visibility, approving transactions, creating grants, approving server updates, or changing Shamir parameters.
-
-### 3.6 Sleeping and Waking Recovery Operators
-
-By default, Recovery Operators are **sleeping** and do not participate in any active flow.
-
-Any ordinary operator may request that Recovery Operators **wake up**.
-
-Any ordinary operator may also cancel a pending wake-up request.
-
-This creates a dispute window before recovery powers become active. The default wake-up delay is **14 days**.
-
-Recovery Operators are therefore part of the break-glass recovery path rather than the normal operating quorum.
-
-The high-level recovery flow is:
-
-```mermaid
-sequenceDiagram
-    autonumber
-    actor Op as Ordinary Operator
-    participant Server
-    actor Other as Other Operator
-    actor Rec as Recovery Operator
-
-    Op->>Server: Request recovery wake-up
-    Server-->>Op: Wake-up pending
-    Note over Server: Default dispute window: 14 days
-
-    alt Wake-up cancelled during dispute window
-        Other->>Server: Cancel wake-up
-        Server-->>Op: Recovery cancelled
-        Server-->>Rec: Stay sleeping
-    else No cancellation for 14 days
-        Server-->>Rec: Wake up
-        Rec->>Server: Join recovery flow
-        critical Recovery authority
-            Rec->>Server: Participate in unseal
-            Rec->>Server: Vote on operator replacement
-        end
-        Server-->>Op: Recovery mode active
-    end
-```
-
-### 3.7 Committee Formation
-
-There are two ways to form a multi-operator committee:
-
-- convert an existing single-operator vault by adding new operators
-- bootstrap an unbootstrapped vault directly into multi-operator mode
-
-In both cases, committee formation is a coordinated process. Arbiter does not allow multi-operator custody to emerge implicitly from unrelated registrations.
-
-### 3.8 Bootstrapping an Unbootstrapped Vault into Multi-Operator Mode
-
-When an unbootstrapped vault is initialized as a multi-operator vault, the setup proceeds as follows:
-
-1. An operator connects to the unbootstrapped vault using an Operator and the bootstrap token.
-2. During bootstrap setup, that operator declares:
-   - the total number of ordinary operators
-   - the total number of Recovery Operators
-3. The vault enters **multi-bootstrap mode**.
-4. While in multi-bootstrap mode:
-   - every ordinary operator must connect with an Operator using the bootstrap token
-   - every Recovery Operator must also connect using the bootstrap token
-   - each participant is registered individually
-   - each participant's share is created and protected with that participant's credentials
-5. The vault is considered fully bootstrapped only after all declared operator and recovery-share registrations have completed successfully.
-
-This means the operator and recovery set is fixed at bootstrap completion time, based on the counts declared when multi-bootstrap mode was entered.
-
-### 3.9 Special Bootstrap Constraint for Two-Operator Vaults
-
-If a vault is declared with exactly **2 ordinary operators**, Arbiter requires at least **1 Recovery Operator** to be configured during bootstrap.
-
-This prevents the worst-case custody failure in which a `2-of-2` operator set becomes permanently unrecoverable after loss of a single operator.
-
----
-
-## 4. Server Identity
-
-The server proves its identity using TLS with a self-signed certificate. The TLS private key is generated on first run and is long-term; no rotation mechanism exists yet due to the complexity of multi-peer coordination.
-
-Peers verify the server by its **public key fingerprint**:
-
-- **Operator (local):** Receives the fingerprint automatically through the bootstrap token.
-- **Operator (remote) / SDK Client:** Must receive the fingerprint out-of-band.
-
-> A streamlined setup mechanism using a single connection string is planned but not yet implemented.
-
----
-
-## 5. Key Management
-
-### 5.1 Key Hierarchy
-
-There are three layers of keys:
-
-| Key | Encrypts | Encrypted by |
-|---|---|---|
-| **User key** (password) | Root key | — (derived from user input) |
-| **Root key** | Wallet keys | User key |
-| **Wallet keys** | — (used for signing) | Root key |
-
-This layered design enables:
-
-- **Password rotation** without re-encrypting every wallet key (only the root key is re-encrypted).
-- **Root key rotation** without requiring the user to change their password.
-
-### 5.2 Encryption at Rest
-
-The database stores everything in encrypted form using symmetric AEAD. The encryption scheme is versioned to support transparent migration — when the vault unseals, Arbiter automatically re-encrypts any entries that are behind the current scheme version. See [IMPLEMENTATION.md](IMPLEMENTATION.md) for the specific scheme and versioning mechanism.
-
----
-
-## 6. Vault Lifecycle
-
-### 6.1 Sealed State
-
-On boot, the root key is encrypted and the server cannot perform any signing operations. This state is called **Sealed**.
-
-### 6.2 Unseal Flow
-
-To transition to the **Unsealed** state, an Operator must provide the password:
-
-1. The Operator initiates an unseal request.
-2. The server generates a one-time key pair and returns the public key.
-3. The Operator encrypts the user's password with this one-time public key and sends the ciphertext to the server.
-4. The server decrypts and verifies the password:
-   - **Success:** The root key is decrypted and placed into a hardened memory cell. The server transitions to `Unsealed`. Any entries pending encryption scheme migration are re-encrypted.
-   - **Failure:** The server returns an error indicating the password is incorrect.
-
-### 6.3 Memory Protection
-
-Once unsealed, the root key must be protected in memory against:
-
-- Memory dumps
-- Page swaps to disk
-- Hibernation files
-
-See [IMPLEMENTATION.md](IMPLEMENTATION.md) for the current and planned memory protection approaches.
-
----
-
-## 7. Permission Engine
-
-### 7.1 Fundamental Rules
-
-- SDK clients have **no access by default**.
-- Access is granted **explicitly** by an Operator.
-- Grants are scoped to **specific wallets** and governed by **policies**.
-
-Each blockchain requires its own policy system due to differences in static transaction analysis. Currently, only EVM is supported; Solana support is planned.
-
-Arbiter is also responsible for ensuring that **transaction nonces are never reused**.
-
-### 7.2 EVM Policies
-
-Every EVM grant is scoped to a specific **wallet** and **chain ID**.
-
-#### 7.2.0 Transaction Signing Sequence
-
-The high-level interaction order is:
-
-```mermaid
-sequenceDiagram
-    autonumber
-    actor SDK as SDK Client
-    participant Server
-    participant operator as Operator
-
-    SDK->>Server: SignTransactionRequest
-    Server->>Server: Resolve wallet and wallet visibility
-    alt Visibility approval required
-        Server->>operator: Ask for wallet visibility approval
-        operator-->>Server: Vote result
-    end
-    Server->>Server: Evaluate transaction
-    Server->>Server: Load grant and limits context
-    alt Grant approval required
-        Server->>operator: Ask for execution / grant approval
-        operator-->>Server: Vote result
-        opt Create persistent grant
-            Server->>Server: Create and store grant
-        end
-        Server->>Server: Retry evaluation
-    end
-    critical Final authorization path
-        Server->>Server: Check limits and record execution
-        Server-->>Server: Signature or evaluation error
-    end
-    Server-->>SDK: Signature or error
-```
-
-#### 7.2.1 Transaction Sub-Grants
-
-Arbiter maintains an ever-expanding database of known contracts and their ABIs. Based on contract knowledge, transaction requests fall into three categories:
-
-**1. Known contract (ABI available)**
-
-The transaction can be decoded and presented with semantic meaning. For example: *"Client X wants to transfer Y USDT to address Z."*
-
-Available restrictions:
-- Volume limits (e.g., "no more than 10,000 tokens ever")
-- Rate limits (e.g., "no more than 100 tokens per hour")
-
-**2. Unknown contract (no ABI)**
-
-The transaction cannot be decoded, so its effects are opaque — it could do anything, including draining all tokens. The user is warned, and if approved, access is granted to all interactions with the contract (matched by the `to` field).
-
-Available restrictions:
-- Transaction count limits (e.g., "no more than 100 transactions ever")
-- Rate limits (e.g., "no more than 5 transactions per hour")
-
-**3. Plain ether transfer (no calldata)**
-
-These transactions have no `calldata` and therefore cannot interact with contracts. They can be subject to the same volume and rate restrictions as above.
-
-#### 7.2.2 Global Limits
-
-In addition to sub-grant-specific restrictions, the following limits can be applied across all grant types:
-
-- **Gas limit** — Maximum gas per transaction.
-- **Time-window restrictions** — e.g., signing allowed only 08:00–20:00 on Mondays and Thursdays.

mise.lock

@@ -1,109 +1,84 @@
 # @generated - this file is auto-generated by `mise lock` https://mise.jdx.dev/dev-tools/mise-lock.html
 
 [[tools.ast-grep]]
-version = "0.42.1"
+version = "0.42.0"
 backend = "aqua:ast-grep/ast-grep"
 
 [tools.ast-grep."platforms.linux-arm64"]
-checksum = "sha256:3ba383839044cf9817929435f5ce0027f91d06931e8efb32d942e58d73d92be5"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-unknown-linux-gnu.zip"
-url_api = "https://api.github.com/repos/ast-grep/ast-grep/releases/assets/388772218"
-
-[tools.ast-grep."platforms.linux-arm64-musl"]
-checksum = "sha256:3ba383839044cf9817929435f5ce0027f91d06931e8efb32d942e58d73d92be5"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-unknown-linux-gnu.zip"
+checksum = "sha256:5c830eae8456569e2f7212434ed9c238f58dca412d76045418ed6d394a755836"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-aarch64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.linux-x64"]
-checksum = "sha256:5de8b87cba67fc8dc3e239d54b6484802ad745a7ae3de76be4fe89661dc52657"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-unknown-linux-gnu.zip"
-url_api = "https://api.github.com/repos/ast-grep/ast-grep/releases/assets/388771275"
-
-[tools.ast-grep."platforms.linux-x64-musl"]
-checksum = "sha256:5de8b87cba67fc8dc3e239d54b6484802ad745a7ae3de76be4fe89661dc52657"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-unknown-linux-gnu.zip"
+checksum = "sha256:e825a05603f0bcc4cd9076c4cc8c9abd6d008b7cd07d9aa3cc323ba4b8606651"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.macos-arm64"]
-checksum = "sha256:c3961d8e8a4ee0ce2d0d98c7beeb168bb331cdc766b53630118a7b6c4fd39015"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-apple-darwin.zip"
-url_api = "https://api.github.com/repos/ast-grep/ast-grep/releases/assets/388770234"
+checksum = "sha256:fc300d5293b1c770a5aece03a8a193b92e71e87cec726c28096990691a582620"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-aarch64-apple-darwin.zip"
 
 [tools.ast-grep."platforms.macos-x64"]
-checksum = "sha256:a038965bfd7fe44257c771cdf8918dc3467dd8ec0eef673b8b14f639b144cdbd"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-apple-darwin.zip"
-url_api = "https://api.github.com/repos/ast-grep/ast-grep/releases/assets/388770498"
+checksum = "sha256:979ffe611327056f4730a1ae71b0209b3b830f58b22c6ed194cda34f55400db2"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-apple-darwin.zip"
 
 [tools.ast-grep."platforms.windows-x64"]
-checksum = "sha256:fe34f631bb24c08ad146f92ca2a92971a53d179461b509fd8d32dc863bff9f83"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-pc-windows-msvc.zip"
-url_api = "https://api.github.com/repos/ast-grep/ast-grep/releases/assets/388771363"
+checksum = "sha256:55836fa1b2c65dc7d61615a4d9368622a0d2371a76d28b9a165e5a3ab6ae32a4"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-pc-windows-msvc.zip"
 
 [[tools."cargo:cargo-audit"]]
 version = "0.22.1"
 backend = "cargo:cargo-audit"
 
 [[tools."cargo:cargo-edit"]]
-version = "0.13.10"
+version = "0.13.9"
 backend = "cargo:cargo-edit"
 
+[[tools."cargo:cargo-features"]]
+version = "1.0.0"
+backend = "cargo:cargo-features"
+
 [[tools."cargo:cargo-features-manager"]]
-version = "0.12.0"
+version = "0.11.1"
 backend = "cargo:cargo-features-manager"
 
 [[tools."cargo:cargo-insta"]]
-version = "1.47.2"
+version = "1.46.3"
 backend = "cargo:cargo-insta"
 
-[[tools."cargo:cargo-mutants"]]
-version = "27.0.0"
-backend = "cargo:cargo-mutants"
-
 [[tools."cargo:cargo-nextest"]]
-version = "0.9.133"
+version = "0.9.126"
 backend = "cargo:cargo-nextest"
 
 [[tools."cargo:cargo-shear"]]
-version = "1.13.4"
+version = "1.9.1"
 backend = "cargo:cargo-shear"
 
 [[tools."cargo:cargo-vet"]]
 version = "0.10.2"
 backend = "cargo:cargo-vet"
 
+[[tools."cargo:diesel-cli"]]
+version = "2.3.6"
+backend = "cargo:diesel-cli"
+
+[tools."cargo:diesel-cli".options]
+default-features = "false"
+features = "sqlite,sqlite-bundled"
+
 [[tools."cargo:diesel_cli"]]
-version = "2.3.7"
+version = "2.3.6"
 backend = "cargo:diesel_cli"
 
 [tools."cargo:diesel_cli".options]
 default-features = "false"
 features = "sqlite,sqlite-bundled"
 
-[[tools."cargo:flutter_rust_bridge_codegen"]]
-version = "2.12.0"
-backend = "cargo:flutter_rust_bridge_codegen"
+[[tools."cargo:rinf_cli"]]
+version = "8.9.1"
+backend = "cargo:rinf_cli"
 
 [[tools.flutter]]
-version = "3.41.7-stable"
-backend = "http:flutter"
-
-[tools.flutter."platforms.linux-x64"]
-checksum = "sha256:f344d5057db52abc2a63cd3a7c7370957b7685d1fca5e5fbe2ce4dfe74657a79"
-url = "https://storage.googleapis.com/flutter_infra_release/releases/stable/linux/flutter_linux_3.41.7-stable.tar.xz"
-
-[tools.flutter."platforms.linux-x64-musl"]
-checksum = "sha256:f344d5057db52abc2a63cd3a7c7370957b7685d1fca5e5fbe2ce4dfe74657a79"
-url = "https://storage.googleapis.com/flutter_infra_release/releases/stable/linux/flutter_linux_3.41.7-stable.tar.xz"
-
-[tools.flutter."platforms.macos-arm64"]
-checksum = "sha256:2e3e6af44d1adccf695deff52e5e4c8beb10e5625066b27ad082b38b83ef805e"
-url = "https://storage.googleapis.com/flutter_infra_release/releases/stable/macos/flutter_macos_arm64_3.41.7-stable.zip"
-
-[tools.flutter."platforms.macos-x64"]
-checksum = "sha256:a0b9af49e6e1a6800f31a408b98c1d7bd51e98650a8b9ebcd77168b48c916ff0"
-url = "https://storage.googleapis.com/flutter_infra_release/releases/stable/macos/flutter_macos_3.41.7-stable.zip"
-
-[tools.flutter."platforms.windows-x64"]
-checksum = "sha256:de17b513b740a931c5dbc3f96b5a659c1612dfe6b5e1f910c5ad954a8bac17ee"
-url = "https://storage.googleapis.com/flutter_infra_release/releases/stable/windows/flutter_windows_3.41.7-stable.zip"
+version = "3.38.9-stable"
+backend = "asdf:flutter"
 
 [[tools.protoc]]
 version = "29.6"
@@ -112,80 +87,47 @@ backend = "aqua:protocolbuffers/protobuf/protoc"
 [tools.protoc."platforms.linux-arm64"]
 checksum = "sha256:2594ff4fcae8cb57310d394d0961b236190ad9c5efbfdf1f597ea471d424fe79"
 url = "https://github.com/protocolbuffers/protobuf/releases/download/v29.6/protoc-29.6-linux-aarch_64.zip"
-url_api = "https://api.github.com/repos/protocolbuffers/protobuf/releases/assets/350795076"
-
-[tools.protoc."platforms.linux-arm64-musl"]
-checksum = "sha256:2594ff4fcae8cb57310d394d0961b236190ad9c5efbfdf1f597ea471d424fe79"
-url = "https://github.com/protocolbuffers/protobuf/releases/download/v29.6/protoc-29.6-linux-aarch_64.zip"
-url_api = "https://api.github.com/repos/protocolbuffers/protobuf/releases/assets/350795076"
 
 [tools.protoc."platforms.linux-x64"]
 checksum = "sha256:48785a926e73ffa3f68e2f22b14e7b849620c7a1d36809ac9249a5495e280323"
 url = "https://github.com/protocolbuffers/protobuf/releases/download/v29.6/protoc-29.6-linux-x86_64.zip"
-url_api = "https://api.github.com/repos/protocolbuffers/protobuf/releases/assets/350795083"
-
-[tools.protoc."platforms.linux-x64-musl"]
-checksum = "sha256:48785a926e73ffa3f68e2f22b14e7b849620c7a1d36809ac9249a5495e280323"
-url = "https://github.com/protocolbuffers/protobuf/releases/download/v29.6/protoc-29.6-linux-x86_64.zip"
-url_api = "https://api.github.com/repos/protocolbuffers/protobuf/releases/assets/350795083"
 
 [tools.protoc."platforms.macos-arm64"]
 checksum = "sha256:b9576b5fa1a1ef3fe13a8c91d9d8204b46545759bea5ae155cd6ba2ea4cdaeed"
 url = "https://github.com/protocolbuffers/protobuf/releases/download/v29.6/protoc-29.6-osx-aarch_64.zip"
-url_api = "https://api.github.com/repos/protocolbuffers/protobuf/releases/assets/350795082"
 
 [tools.protoc."platforms.macos-x64"]
 checksum = "sha256:312f04713946921cc0187ef34df80241ddca1bab6f564c636885fd2cc90d3f88"
 url = "https://github.com/protocolbuffers/protobuf/releases/download/v29.6/protoc-29.6-osx-x86_64.zip"
-url_api = "https://api.github.com/repos/protocolbuffers/protobuf/releases/assets/350795085"
 
 [tools.protoc."platforms.windows-x64"]
 checksum = "sha256:1ebd7c87baffb9f1c47169b640872bf5fb1e4408079c691af527be9561d8f6f7"
 url = "https://github.com/protocolbuffers/protobuf/releases/download/v29.6/protoc-29.6-win64.zip"
-url_api = "https://api.github.com/repos/protocolbuffers/protobuf/releases/assets/350795088"
 
 [[tools.python]]
-version = "3.14.4"
+version = "3.14.3"
 backend = "core:python"
 
 [tools.python."platforms.linux-arm64"]
-checksum = "sha256:b8b597fdb2f8dccdc502c11947b60a4b65eb6bce79cfa60c7ccf9b6e8352c60a"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-aarch64-unknown-linux-gnu-install_only_stripped.tar.gz"
-provenance = "github-attestations"
-
-[tools.python."platforms.linux-arm64-musl"]
-checksum = "sha256:a10687b226e0941632569836bc1d8fa6353a8e3e8424316467ca9cdf220b983d"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-aarch64-unknown-linux-musl-install_only_stripped.tar.gz"
-provenance = "github-attestations"
+checksum = "sha256:be0f4dc2932f762292b27d46ea7d3e8e66ddf3969a5eb0254a229015ed402625"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260303/cpython-3.14.3+20260303-aarch64-unknown-linux-gnu-install_only_stripped.tar.gz"
 
 [tools.python."platforms.linux-x64"]
-checksum = "sha256:fe9a9c32d13870af632cbac3dfc7528ae53597e94472aa4c7d6a42e8166136cd"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz"
-provenance = "github-attestations"
-
-[tools.python."platforms.linux-x64-musl"]
-checksum = "sha256:d6005226cd24e780630626232c7a63243d4885fdf975dcf930a0758a0759ce14"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-x86_64-unknown-linux-musl-install_only_stripped.tar.gz"
-provenance = "github-attestations"
+checksum = "sha256:0a73413f89efd417871876c9accaab28a9d1e3cd6358fbfff171a38ec99302f0"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260303/cpython-3.14.3+20260303-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz"
 
 [tools.python."platforms.macos-arm64"]
-checksum = "sha256:6f304f4ec30854611f23316578302235fb517cd970519ecdd11a8c4db87fd843"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-aarch64-apple-darwin-install_only_stripped.tar.gz"
-provenance = "github-attestations"
+checksum = "sha256:4703cdf18b26798fde7b49b6b66149674c25f97127be6a10dbcf29309bdcdcdb"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260303/cpython-3.14.3+20260303-aarch64-apple-darwin-install_only_stripped.tar.gz"
 
 [tools.python."platforms.macos-x64"]
-checksum = "sha256:d51250a32fa5d9f0799c7bcb71720c27b10a3afd4a7de288120f96085d508a5a"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-x86_64-apple-darwin-install_only_stripped.tar.gz"
-provenance = "github-attestations"
+checksum = "sha256:76f1cc26e3d262eae8ca546a93e8bded10cf0323613f7e246fea2e10a8115eb7"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260303/cpython-3.14.3+20260303-x86_64-apple-darwin-install_only_stripped.tar.gz"
 
 [tools.python."platforms.windows-x64"]
-checksum = "sha256:a976991dcd085c1bb5d9a8084823a6bc8b7f9b079d8c432574a6ddd68c3a6fe1"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-x86_64-pc-windows-msvc-install_only_stripped.tar.gz"
-provenance = "github-attestations"
+checksum = "sha256:950c5f21a015c1bdd1337f233456df2470fab71e4d794407d27a84cb8b9909a0"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260303/cpython-3.14.3+20260303-x86_64-pc-windows-msvc-install_only_stripped.tar.gz"
 
 [[tools.rust]]
-version = "1.95.0"
+version = "1.93.0"
 backend = "core:rust"
-
-[tools.rust.options]
-components = "clippy,rust-analyzer"

mise.toml

@@ -1,26 +1,22 @@
 [tools]
-"cargo:diesel_cli" = { version = "2.3.7", features = "sqlite,sqlite-bundled", default-features = "false" }
+"cargo:diesel_cli" = { version = "2.3.6", features = "sqlite,sqlite-bundled", default-features = false }
 "cargo:cargo-audit" = "0.22.1"
 "cargo:cargo-vet" = "0.10.2"
-flutter = "3.41.7-stable"
+flutter = "3.38.9-stable"
 protoc = "29.6"
-rust = { version = "1.95.0", components = "clippy,rust-analyzer" }
-"cargo:cargo-features-manager" = "0.12.0"
-"cargo:cargo-nextest" = "0.9.133"
+"rust" = {version = "1.93.0", components = "clippy"}
+"cargo:cargo-features-manager" = "0.11.1"
+"cargo:cargo-nextest" = "0.9.126"
 "cargo:cargo-shear" = "latest"
-"cargo:cargo-insta" = "1.47.2"
-python = "3.14.4"
-ast-grep = "0.42.1"
-"cargo:cargo-edit" = "0.13.10"
-"cargo:cargo-mutants" = "27.0.0"
-"cargo:flutter_rust_bridge_codegen" = "2.12.0"
+"cargo:cargo-insta" = "1.46.3"
+python = "3.14.3"
+ast-grep = "0.42.0"
+"cargo:cargo-edit" = "0.13.9"
 
 [tasks.codegen]
-sources = ['protobufs/*.proto', 'protobufs/**/*.proto']
-outputs = ['useragent/lib/proto/**']
+sources = ['protobufs/*.proto']
+outputs = ['useragent/lib/proto/*']
 run = '''
 dart pub global activate protoc_plugin && \
-protoc --dart_out=grpc:useragent/lib/proto --proto_path=protobufs/ $(find protobufs -name '*.proto' | sort)
+protoc --dart_out=grpc:useragent/lib/proto --proto_path=protobufs/ protobufs/*.proto
 '''
-
-[tasks.generate_schema]

protobufs/arbiter.proto

@@ -3,7 +3,7 @@ syntax = "proto3";
 package arbiter;
 
 import "client.proto";
-import "operator.proto";
+import "user_agent.proto";
 
 message ServerInfo {
   string version = 1;
@@ -12,5 +12,5 @@ message ServerInfo {
 
 service ArbiterService {
   rpc Client(stream arbiter.client.ClientRequest) returns (stream arbiter.client.ClientResponse);
-  rpc Operator(stream arbiter.operator.OperatorRequest) returns (stream arbiter.operator.OperatorResponse);
+  rpc UserAgent(stream arbiter.user_agent.UserAgentRequest) returns (stream arbiter.user_agent.UserAgentResponse);
 }

protobufs/client.proto

@@ -2,24 +2,56 @@ syntax = "proto3";
 
 package arbiter.client;
 
-import "client/auth.proto";
-import "client/evm.proto";
-import "client/vault.proto";
+import "evm.proto";
+import "google/protobuf/empty.proto";
+
+message AuthChallengeRequest {
+  bytes pubkey = 1;
+}
+
+message AuthChallenge {
+  bytes pubkey = 1;
+  int32 nonce = 2;
+}
+
+message AuthChallengeSolution {
+  bytes signature = 1;
+}
+
+enum AuthResult {
+  AUTH_RESULT_UNSPECIFIED = 0;
+  AUTH_RESULT_SUCCESS = 1;
+  AUTH_RESULT_INVALID_KEY = 2;
+  AUTH_RESULT_INVALID_SIGNATURE = 3;
+  AUTH_RESULT_APPROVAL_DENIED = 4;
+  AUTH_RESULT_NO_USER_AGENTS_ONLINE = 5;
+  AUTH_RESULT_INTERNAL = 6;
+}
+
+enum VaultState {
+  VAULT_STATE_UNSPECIFIED = 0;
+  VAULT_STATE_UNBOOTSTRAPPED = 1;
+  VAULT_STATE_SEALED = 2;
+  VAULT_STATE_UNSEALED = 3;
+  VAULT_STATE_ERROR = 4;
+}
 
 message ClientRequest {
   int32 request_id = 4;
   oneof payload {
-    auth.Request auth = 1;
-    vault.Request vault = 2;
-    evm.Request evm = 3;
+    AuthChallengeRequest auth_challenge_request = 1;
+    AuthChallengeSolution auth_challenge_solution = 2;
+    google.protobuf.Empty query_vault_state = 3;
   }
 }
 
 message ClientResponse {
   optional int32 request_id = 7;
   oneof payload {
-    auth.Response auth = 1;
-    vault.Response vault = 2;
-    evm.Response evm = 3;
+    AuthChallenge auth_challenge = 1;
+    AuthResult auth_result = 2;
+    arbiter.evm.EvmSignTransactionResponse evm_sign_transaction = 3;
+    arbiter.evm.EvmAnalyzeTransactionResponse evm_analyze_transaction = 4;
+    VaultState vault_state = 6;
   }
 }

protobufs/client/auth.proto

@@ -1,43 +0,0 @@
-syntax = "proto3";
-
-package arbiter.client.auth;
-
-import "shared/client.proto";
-
-message AuthChallengeRequest {
-  bytes pubkey = 1;
-  arbiter.shared.ClientInfo client_info = 2;
-}
-
-message AuthChallenge {
-  uint64 timestamp_nanos = 1;
-  bytes random = 2;
-}
-
-message AuthChallengeSolution {
-  bytes signature = 1;
-}
-
-enum AuthResult {
-  AUTH_RESULT_UNSPECIFIED = 0;
-  AUTH_RESULT_SUCCESS = 1;
-  AUTH_RESULT_INVALID_KEY = 2;
-  AUTH_RESULT_INVALID_SIGNATURE = 3;
-  AUTH_RESULT_APPROVAL_DENIED = 4;
-  AUTH_RESULT_NO_OPERATORS_ONLINE = 5;
-  AUTH_RESULT_INTERNAL = 6;
-}
-
-message Request {
-  oneof payload {
-    AuthChallengeRequest challenge_request = 1;
-    AuthChallengeSolution challenge_solution = 2;
-  }
-}
-
-message Response {
-  oneof payload {
-    AuthChallenge challenge = 1;
-    AuthResult result = 2;
-  }
-}

protobufs/client/evm.proto

@@ -1,19 +0,0 @@
-syntax = "proto3";
-
-package arbiter.client.evm;
-
-import "evm.proto";
-
-message Request {
-  oneof payload {
-    arbiter.evm.EvmSignTransactionRequest sign_transaction = 1;
-    arbiter.evm.EvmAnalyzeTransactionRequest analyze_transaction = 2;
-  }
-}
-
-message Response {
-  oneof payload {
-    arbiter.evm.EvmSignTransactionResponse sign_transaction = 1;
-    arbiter.evm.EvmAnalyzeTransactionResponse analyze_transaction = 2;
-  }
-}

protobufs/client/vault.proto

@@ -1,18 +0,0 @@
-syntax = "proto3";
-
-package arbiter.client.vault;
-
-import "google/protobuf/empty.proto";
-import "shared/vault.proto";
-
-message Request {
-  oneof payload {
-    google.protobuf.Empty query_state = 1;
-  }
-}
-
-message Response {
-  oneof payload {
-    arbiter.shared.VaultState state = 1;
-  }
-}

protobufs/evm.proto

@@ -4,7 +4,6 @@ package arbiter.evm;
 
 import "google/protobuf/empty.proto";
 import "google/protobuf/timestamp.proto";
-import "shared/evm.proto";
 
 enum EvmError {
   EVM_ERROR_UNSPECIFIED = 0;
@@ -13,8 +12,7 @@ enum EvmError {
 }
 
 message WalletEntry {
-  int32 id = 1;
-  bytes address = 2; // 20-byte Ethereum address
+  bytes address = 1; // 20-byte Ethereum address
 }
 
 message WalletList {
@@ -48,7 +46,7 @@ message VolumeRateLimit {
 }
 
 message SharedSettings {
-  int32 wallet_access_id = 1;
+  int32 wallet_id = 1;
   uint64 chain_id = 2;
   optional google.protobuf.Timestamp valid_from = 3;
   optional google.protobuf.Timestamp valid_until = 4;
@@ -75,10 +73,75 @@ message SpecificGrant {
   }
 }
 
-// --- Operator grant management ---
+message EtherTransferMeaning {
+  bytes to = 1; // 20-byte Ethereum address
+  bytes value = 2; // U256 as big-endian bytes
+}
+
+message TokenInfo {
+  string symbol = 1;
+  bytes address = 2; // 20-byte Ethereum address
+  uint64 chain_id = 3;
+}
+
+// Mirror of token_transfers::Meaning
+message TokenTransferMeaning {
+  TokenInfo token = 1;
+  bytes to = 2; // 20-byte Ethereum address
+  bytes value = 3; // U256 as big-endian bytes
+}
+
+// Mirror of policies::SpecificMeaning
+message SpecificMeaning {
+  oneof meaning {
+    EtherTransferMeaning ether_transfer = 1;
+    TokenTransferMeaning token_transfer = 2;
+  }
+}
+
+// --- Eval error types ---
+message GasLimitExceededViolation {
+  optional bytes max_gas_fee_per_gas = 1; // U256 as big-endian bytes
+  optional bytes max_priority_fee_per_gas = 2; // U256 as big-endian bytes
+}
+
+message EvalViolation {
+  oneof kind {
+    bytes invalid_target = 1; // 20-byte Ethereum address
+    GasLimitExceededViolation gas_limit_exceeded = 2;
+    google.protobuf.Empty rate_limit_exceeded = 3;
+    google.protobuf.Empty volumetric_limit_exceeded = 4;
+    google.protobuf.Empty invalid_time = 5;
+    google.protobuf.Empty invalid_transaction_type = 6;
+  }
+}
+
+// Transaction was classified but no grant covers it
+message NoMatchingGrantError {
+  SpecificMeaning meaning = 1;
+}
+
+// Transaction was classified and a grant was found, but constraints were violated
+message PolicyViolationsError {
+  SpecificMeaning meaning = 1;
+  repeated EvalViolation violations = 2;
+}
+
+// top-level error returned when transaction evaluation fails
+message TransactionEvalError {
+  oneof kind {
+    google.protobuf.Empty contract_creation_not_supported = 1;
+    google.protobuf.Empty unsupported_transaction_type = 2;
+    NoMatchingGrantError no_matching_grant = 3;
+    PolicyViolationsError policy_violations = 4;
+  }
+}
+
+// --- UserAgent grant management ---
 message EvmGrantCreateRequest {
-  SharedSettings shared = 1;
-  SpecificGrant specific = 2;
+  int32 client_id = 1;
+  SharedSettings shared = 2;
+  SpecificGrant specific = 3;
 }
 
 message EvmGrantCreateResponse {
@@ -102,13 +165,13 @@ message EvmGrantDeleteResponse {
 // Basic grant info returned in grant listings
 message GrantEntry {
   int32 id = 1;
-  int32 wallet_access_id = 2;
+  int32 client_id = 2;
   SharedSettings shared = 3;
   SpecificGrant specific = 4;
 }
 
 message EvmGrantListRequest {
-  optional int32 wallet_access_id = 1;
+  optional int32 wallet_id = 1;
 }
 
 message EvmGrantListResponse {
@@ -134,7 +197,7 @@ message EvmSignTransactionRequest {
 message EvmSignTransactionResponse {
   oneof result {
     bytes signature = 1; // 65-byte signature: r[32] || s[32] || v[1]
-    arbiter.shared.evm.TransactionEvalError eval_error = 2;
+    TransactionEvalError eval_error = 2;
     EvmError error = 3;
   }
 }
@@ -146,8 +209,8 @@ message EvmAnalyzeTransactionRequest {
 
 message EvmAnalyzeTransactionResponse {
   oneof result {
-    arbiter.shared.evm.SpecificMeaning meaning = 1;
-    arbiter.shared.evm.TransactionEvalError eval_error = 2;
+    SpecificMeaning meaning = 1;
+    TransactionEvalError eval_error = 2;
     EvmError error = 3;
   }
 }

protobufs/operator.proto

@@ -1,31 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator;
-
-import "operator/auth.proto";
-import "operator/evm.proto";
-import "operator/governance.proto";
-import "operator/sdk_client.proto";
-import "operator/vault/vault.proto";
-
-message OperatorRequest {
-  int32 id = 16;
-  oneof payload {
-    auth.Request            auth        = 1;
-    vault.Request           vault       = 2;
-    evm.Request             evm         = 3;
-    sdk_client.Request      sdk_client  = 4;
-    governance.Request      governance  = 5;
-  }
-}
-
-message OperatorResponse {
-  optional int32 id = 16;
-  oneof payload {
-    auth.Response           auth        = 1;
-    vault.Response          vault       = 2;
-    evm.Response            evm         = 3;
-    sdk_client.Response     sdk_client  = 4;
-    governance.Response     governance  = 5;
-  }
-}

protobufs/operator/auth.proto

@@ -1,41 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.auth;
-
-message AuthChallengeRequest {
-  bytes pubkey = 1;
-  optional string bootstrap_token = 2;
-}
-
-message AuthChallenge {
-  uint64 timestamp_nanos = 1;
-  bytes random = 2;
-}
-
-message AuthChallengeSolution {
-  bytes signature = 1;
-}
-
-enum AuthResult {
-  AUTH_RESULT_UNSPECIFIED = 0;
-  AUTH_RESULT_SUCCESS = 1;
-  AUTH_RESULT_INVALID_KEY = 2;
-  AUTH_RESULT_INVALID_SIGNATURE = 3;
-  AUTH_RESULT_BOOTSTRAP_REQUIRED = 4;
-  AUTH_RESULT_TOKEN_INVALID = 5;
-  AUTH_RESULT_INTERNAL = 6;
-}
-
-message Request {
-  oneof payload {
-    AuthChallengeRequest challenge_request = 1;
-    AuthChallengeSolution challenge_solution = 2;
-  }
-}
-
-message Response {
-  oneof payload {
-    AuthChallenge challenge = 1;
-    AuthResult result = 2;
-  }
-}

protobufs/operator/evm.proto

@@ -1,33 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.evm;
-
-import "evm.proto";
-import "google/protobuf/empty.proto";
-
-message SignTransactionRequest {
-  int32 client_id = 1;
-  arbiter.evm.EvmSignTransactionRequest request = 2;
-}
-
-message Request {
-  oneof payload {
-    google.protobuf.Empty wallet_create = 1;
-    google.protobuf.Empty wallet_list = 2;
-    arbiter.evm.EvmGrantCreateRequest grant_create = 3;
-    arbiter.evm.EvmGrantDeleteRequest grant_delete = 4;
-    arbiter.evm.EvmGrantListRequest grant_list = 5;
-    SignTransactionRequest sign_transaction = 6;
-  }
-}
-
-message Response {
-  oneof payload {
-    arbiter.evm.WalletCreateResponse wallet_create = 1;
-    arbiter.evm.WalletListResponse wallet_list = 2;
-    arbiter.evm.EvmGrantCreateResponse grant_create = 3;
-    arbiter.evm.EvmGrantDeleteResponse grant_delete = 4;
-    arbiter.evm.EvmGrantListResponse grant_list = 5;
-    arbiter.evm.EvmSignTransactionResponse sign_transaction = 6;
-  }
-}

protobufs/operator/governance.proto

@@ -1,131 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.governance;
-
-import "google/protobuf/empty.proto";
-
-message Request {
-  oneof payload {
-    CreateProposalRequest create = 1;
-    CastVoteRequest       vote   = 2;
-    QueryPendingRequest   query  = 3;
-  }
-}
-
-message CreateProposalRequest {
-  oneof kind {
-    ApproveSdkClientPayload         approve_sdk_client          = 1;
-    GrantWalletAccessPayload        grant_wallet_access         = 2;
-    ReplaceOperatorPayload          replace_operator            = 3;
-    google.protobuf.Empty           trigger_rekey               = 4;
-    ApprovePersistentGrantPayload   approve_persistent_grant    = 5;
-    ApproveOneOffTransactionPayload approve_one_off_transaction = 6;
-  }
-  optional uint32 ttl_secs = 7;
-}
-
-message ReplaceOperatorPayload {
-  int32 old_operator_id = 1;
-  bytes new_pubkey      = 2;
-}
-
-message ApproveSdkClientPayload {
-  int32 client_id = 1;
-}
-
-message GrantWalletAccessPayload {
-  int32 wallet_id = 1;
-  int32 client_id = 2;
-}
-
-message CastVoteRequest {
-  int32 proposal_id = 1;
-  bool  approve     = 2;
-  bytes signature   = 3;
-}
-
-message QueryPendingRequest {}
-
-message Response {
-  oneof payload {
-    CreateProposalResponse created = 1;
-    VoteResponse           voted   = 2;
-    QueryPendingResponse   pending = 3;
-  }
-}
-
-message CreateProposalResponse {
-  int32 proposal_id = 1;
-}
-
-message VoteResponse {
-  VoteOutcome outcome = 1;
-}
-
-enum VoteOutcome {
-  VOTE_OUTCOME_UNSPECIFIED = 0;
-  VOTE_OUTCOME_PENDING     = 1;
-  VOTE_OUTCOME_APPROVED    = 2;
-  VOTE_OUTCOME_REJECTED    = 3;
-}
-
-message ProposalSummary {
-  int32  id            = 1;
-  string kind          = 2;
-  int32  initiator_id  = 3;
-  int64  expires_at    = 4;
-  int64  approve_count = 5;
-  int64  reject_count  = 6;
-}
-
-message QueryPendingResponse {
-  repeated ProposalSummary proposals = 1;
-}
-
-message TransactionRateLimitProto {
-  uint32 count       = 1;
-  int64  window_secs = 2;
-}
-
-message VolumeLimitProto {
-  bytes max_volume  = 1;
-  int64 window_secs = 2;
-}
-
-message EtherTransferSpecProto {
-  repeated bytes   targets = 1;
-  VolumeLimitProto limit   = 2;
-}
-
-message TokenTransferSpecProto {
-  bytes                     token_contract = 1;
-  optional bytes            target         = 2;
-  repeated VolumeLimitProto volume_limits  = 3;
-}
-
-message ApproveOneOffTransactionPayload {
-  int32  client_id                = 1;
-  bytes  wallet_address           = 2;
-  uint64 chain_id                 = 3;
-  uint64 nonce                    = 4;
-  uint64 gas_limit                = 5;
-  bytes  max_fee_per_gas          = 6;
-  bytes  max_priority_fee_per_gas = 7;
-  bytes  to                       = 8;
-  bytes  value                    = 9;
-  bytes  input                    = 10;
-}
-
-message ApprovePersistentGrantPayload {
-  int32                              wallet_access_id         = 1;
-  uint64                             chain_id                 = 2;
-  optional int64                     valid_from_secs          = 3;
-  optional int64                     valid_until_secs         = 4;
-  optional bytes                     max_gas_fee_per_gas      = 5;
-  optional bytes                     max_priority_fee_per_gas = 6;
-  optional TransactionRateLimitProto rate_limit               = 7;
-  oneof specific {
-    EtherTransferSpecProto ether_transfer = 8;
-    TokenTransferSpecProto token_transfer = 9;
-  }
-}

protobufs/operator/sdk_client.proto

@@ -1,100 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.sdk_client;
-
-import "shared/client.proto";
-import "google/protobuf/empty.proto";
-
-enum Error {
-  ERROR_UNSPECIFIED = 0;
-  ERROR_ALREADY_EXISTS = 1;
-  ERROR_NOT_FOUND = 2;
-  ERROR_HAS_RELATED_DATA = 3; // hard-delete blocked by FK (client has grants or transaction logs)
-  ERROR_INTERNAL = 4;
-}
-
-message RevokeRequest {
-  int32 client_id = 1;
-}
-
-message Entry {
-  int32 id = 1;
-  bytes pubkey = 2;
-  arbiter.shared.ClientInfo info = 3;
-  int32 created_at = 4;
-}
-
-message List {
-  repeated Entry clients = 1;
-}
-
-message RevokeResponse {
-  oneof result {
-    google.protobuf.Empty ok = 1;
-    Error error = 2;
-  }
-}
-
-message ListResponse {
-  oneof result {
-    List clients = 1;
-    Error error = 2;
-  }
-}
-
-message ConnectionRequest {
-  bytes pubkey = 1;
-  arbiter.shared.ClientInfo info = 2;
-}
-
-message ConnectionResponse {
-  bool approved = 1;
-  bytes pubkey = 2;
-}
-
-message ConnectionCancel {
-  bytes pubkey = 1;
-}
-
-message WalletAccess {
-  int32 wallet_id = 1;
-  int32 sdk_client_id = 2;
-}
-
-message WalletAccessEntry {
-  int32 id = 1;
-  WalletAccess access = 2;
-}
-
-message GrantWalletAccess {
-  repeated WalletAccess accesses = 1;
-}
-
-message RevokeWalletAccess {
-  repeated int32 accesses = 1;
-}
-
-message ListWalletAccessResponse {
-  repeated WalletAccessEntry accesses = 1;
-}
-
-message Request {
-  oneof payload {
-    ConnectionResponse connection_response = 1;
-    RevokeRequest revoke = 2;
-    google.protobuf.Empty list = 3;
-    GrantWalletAccess grant_wallet_access = 4;
-    RevokeWalletAccess revoke_wallet_access = 5;
-    google.protobuf.Empty list_wallet_access = 6;
-  }
-}
-
-message Response {
-  oneof payload {
-    ConnectionRequest connection_request = 1;
-    ConnectionCancel connection_cancel = 2;
-    RevokeResponse revoke = 3;
-    ListResponse list = 4;
-    ListWalletAccessResponse list_wallet_access = 5;
-  }
-}

protobufs/operator/vault/bootstrap.proto

@@ -1,43 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.vault.bootstrap;
-
-message BootstrapEncryptedKey {
-  bytes nonce = 1;
-  bytes ciphertext = 2;
-  bytes associated_data = 3;
-}
-
-message DeclareCommittee {
-  uint32 count          = 1;
-  uint32 recovery_count = 2;
-}
-
-message ContributePassphrase {
-  bytes passphrase = 1;
-}
-
-message ContributeRecoveryPassphrase {
-  bytes passphrase = 1;
-}
-
-enum BootstrapResult {
-  BOOTSTRAP_RESULT_UNSPECIFIED = 0;
-  BOOTSTRAP_RESULT_SUCCESS = 1;
-  BOOTSTRAP_RESULT_ALREADY_BOOTSTRAPPED = 2;
-  BOOTSTRAP_RESULT_INVALID_KEY = 3;
-  BOOTSTRAP_RESULT_AWAITING_CONTRIBUTIONS = 4;
-}
-
-message Request {
-  oneof payload {
-    BootstrapEncryptedKey        encrypted_key                    = 2;
-    DeclareCommittee             declare_committee                = 3;
-    ContributePassphrase         contribute_passphrase            = 4;
-    ContributeRecoveryPassphrase contribute_recovery_passphrase   = 5;
-  }
-}
-
-message Response {
-  BootstrapResult result = 1;
-}

protobufs/operator/vault/rekey.proto

@@ -1,29 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.vault.rekey;
-
-message ContributePassphrase {
-  bytes passphrase = 1;
-}
-
-message ContributeRecoveryPassphrase {
-  bytes passphrase = 1;
-}
-
-enum RekeyResult {
-  REKEY_RESULT_UNSPECIFIED            = 0;
-  REKEY_RESULT_SUCCESS                = 1;
-  REKEY_RESULT_AWAITING_CONTRIBUTIONS = 2;
-  REKEY_RESULT_NOT_IN_PROGRESS        = 3;
-}
-
-message Request {
-  oneof payload {
-    ContributePassphrase         contribute_passphrase          = 1;
-    ContributeRecoveryPassphrase contribute_recovery_passphrase = 2;
-  }
-}
-
-message Response {
-  RekeyResult result = 1;
-}

protobufs/operator/vault/unseal.proto

@@ -1,48 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.vault.unseal;
-
-message UnsealStart {
-  bytes client_pubkey = 1;
-}
-
-message UnsealStartResponse {
-  bytes server_pubkey = 1;
-}
-message UnsealEncryptedKey {
-  bytes nonce = 1;
-  bytes ciphertext = 2;
-  bytes associated_data = 3;
-}
-
-message ContributePassphrase {
-  bytes passphrase = 1;
-}
-
-message ContributeRecoveryPassphrase {
-  bytes passphrase = 1;
-}
-
-enum UnsealResult {
-  UNSEAL_RESULT_UNSPECIFIED = 0;
-  UNSEAL_RESULT_SUCCESS = 1;
-  UNSEAL_RESULT_INVALID_KEY = 2;
-  UNSEAL_RESULT_UNBOOTSTRAPPED = 3;
-  UNSEAL_RESULT_AWAITING_CONTRIBUTIONS = 4;
-}
-
-message Request {
-  oneof payload {
-    UnsealStart                  start                          = 1;
-    UnsealEncryptedKey           encrypted_key                  = 2;
-    ContributePassphrase         contribute_passphrase          = 3;
-    ContributeRecoveryPassphrase contribute_recovery_passphrase = 4;
-  }
-}
-
-message Response {
-  oneof payload {
-    UnsealStartResponse start = 1;
-    UnsealResult result = 2;
-  }
-}

protobufs/operator/vault/vault.proto

@@ -1,27 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.vault;
-
-import "google/protobuf/empty.proto";
-import "shared/vault.proto";
-import "operator/vault/bootstrap.proto";
-import "operator/vault/rekey.proto";
-import "operator/vault/unseal.proto";
-
-message Request {
-  oneof payload {
-    google.protobuf.Empty query_state = 1;
-    unseal.Request        unseal      = 2;
-    bootstrap.Request     bootstrap   = 3;
-    rekey.Request         rekey       = 4;
-  }
-}
-
-message Response {
-  oneof payload {
-    arbiter.shared.VaultState state     = 1;
-    unseal.Response           unseal    = 2;
-    bootstrap.Response        bootstrap = 3;
-    rekey.Response            rekey     = 4;
-  }
-}

protobufs/shared/client.proto

@@ -1,9 +0,0 @@
-syntax = "proto3";
-
-package arbiter.shared;
-
-message ClientInfo {
-  string name = 1;
-  optional string description = 2;
-  optional string version = 3;
-}

protobufs/shared/evm.proto

@@ -1,74 +0,0 @@
-syntax = "proto3";
-
-package arbiter.shared.evm;
-
-import "google/protobuf/empty.proto";
-
-message EtherTransferMeaning {
-  bytes to = 1; // 20-byte Ethereum address
-  bytes value = 2; // U256 as big-endian bytes
-}
-
-message TokenInfo {
-  string symbol = 1;
-  bytes address = 2; // 20-byte Ethereum address
-  uint64 chain_id = 3;
-}
-
-// Mirror of token_transfers::Meaning
-message TokenTransferMeaning {
-  TokenInfo token = 1;
-  bytes to = 2; // 20-byte Ethereum address
-  bytes value = 3; // U256 as big-endian bytes
-}
-
-// Mirror of policies::SpecificMeaning
-message SpecificMeaning {
-  oneof meaning {
-    EtherTransferMeaning ether_transfer = 1;
-    TokenTransferMeaning token_transfer = 2;
-  }
-}
-
-message GasLimitExceededViolation {
-  optional bytes max_gas_fee_per_gas = 1; // U256 as big-endian bytes
-  optional bytes max_priority_fee_per_gas = 2; // U256 as big-endian bytes
-}
-
-message EvalViolation {
-  message ChainIdMismatch {
-    uint64 expected = 1;
-    uint64 actual = 2;
-  }
-  oneof kind {
-    bytes invalid_target = 1; // 20-byte Ethereum address
-    GasLimitExceededViolation gas_limit_exceeded = 2;
-    google.protobuf.Empty rate_limit_exceeded = 3;
-    google.protobuf.Empty volumetric_limit_exceeded = 4;
-    google.protobuf.Empty invalid_time = 5;
-    google.protobuf.Empty invalid_transaction_type = 6;
-
-    ChainIdMismatch chain_id_mismatch = 7;
-  }
-}
-
-// Transaction was classified but no grant covers it
-message NoMatchingGrantError {
-  SpecificMeaning meaning = 1;
-}
-
-// Transaction was classified and a grant was found, but constraints were violated
-message PolicyViolationsError {
-  SpecificMeaning meaning = 1;
-  repeated EvalViolation violations = 2;
-}
-
-// top-level error returned when transaction evaluation fails
-message TransactionEvalError {
-  oneof kind {
-    google.protobuf.Empty contract_creation_not_supported = 1;
-    google.protobuf.Empty unsupported_transaction_type = 2;
-    NoMatchingGrantError no_matching_grant = 3;
-    PolicyViolationsError policy_violations = 4;
-  }
-}

protobufs/shared/vault.proto

@@ -1,12 +0,0 @@
-syntax = "proto3";
-
-package arbiter.shared;
-
-enum VaultState {
-  VAULT_STATE_UNSPECIFIED = 0;
-  VAULT_STATE_UNBOOTSTRAPPED = 1;
-  VAULT_STATE_BOOSTRAPPING = 2;
-  VAULT_STATE_SEALED = 3;
-  VAULT_STATE_UNSEALED = 4;
-  VAULT_STATE_ERROR = 5;
-}

protobufs/user_agent.proto

@@ -0,0 +1,179 @@
+syntax = "proto3";
+
+package arbiter.user_agent;
+
+import "evm.proto";
+import "google/protobuf/empty.proto";
+
+enum KeyType {
+  KEY_TYPE_UNSPECIFIED = 0;
+  KEY_TYPE_ED25519 = 1;
+  KEY_TYPE_ECDSA_SECP256K1 = 2;
+  KEY_TYPE_RSA = 3;
+}
+
+// --- SDK client management ---
+
+enum SdkClientError {
+  SDK_CLIENT_ERROR_UNSPECIFIED = 0;
+  SDK_CLIENT_ERROR_ALREADY_EXISTS = 1;
+  SDK_CLIENT_ERROR_NOT_FOUND = 2;
+  SDK_CLIENT_ERROR_HAS_RELATED_DATA = 3; // hard-delete blocked by FK (client has grants or transaction logs)
+  SDK_CLIENT_ERROR_INTERNAL = 4;
+}
+
+message SdkClientApproveRequest {
+  bytes pubkey = 1; // 32-byte ed25519 public key
+}
+
+message SdkClientRevokeRequest {
+  int32 client_id = 1;
+}
+
+message SdkClientEntry {
+  int32 id = 1;
+  bytes pubkey = 2;
+  int32 created_at = 3;
+}
+
+message SdkClientList {
+  repeated SdkClientEntry clients = 1;
+}
+
+message SdkClientApproveResponse {
+  oneof result {
+    SdkClientEntry client = 1;
+    SdkClientError error = 2;
+  }
+}
+
+message SdkClientRevokeResponse {
+  oneof result {
+    google.protobuf.Empty ok = 1;
+    SdkClientError error = 2;
+  }
+}
+
+message SdkClientListResponse {
+  oneof result {
+    SdkClientList clients = 1;
+    SdkClientError error = 2;
+  }
+}
+
+message AuthChallengeRequest {
+  bytes pubkey = 1;
+  optional string bootstrap_token = 2;
+  KeyType key_type = 3;
+}
+
+message AuthChallenge {
+  int32 nonce = 2;
+  reserved 1;
+}
+
+message AuthChallengeSolution {
+  bytes signature = 1;
+}
+
+enum AuthResult {
+  AUTH_RESULT_UNSPECIFIED = 0;
+  AUTH_RESULT_SUCCESS = 1;
+  AUTH_RESULT_INVALID_KEY = 2;
+  AUTH_RESULT_INVALID_SIGNATURE = 3;
+  AUTH_RESULT_BOOTSTRAP_REQUIRED = 4;
+  AUTH_RESULT_TOKEN_INVALID = 5;
+  AUTH_RESULT_INTERNAL = 6;
+}
+
+message UnsealStart {
+  bytes client_pubkey = 1;
+}
+
+message UnsealStartResponse {
+  bytes server_pubkey = 1;
+}
+message UnsealEncryptedKey {
+  bytes nonce = 1;
+  bytes ciphertext = 2;
+  bytes associated_data = 3;
+}
+
+message BootstrapEncryptedKey {
+  bytes nonce = 1;
+  bytes ciphertext = 2;
+  bytes associated_data = 3;
+}
+
+enum UnsealResult {
+  UNSEAL_RESULT_UNSPECIFIED = 0;
+  UNSEAL_RESULT_SUCCESS = 1;
+  UNSEAL_RESULT_INVALID_KEY = 2;
+  UNSEAL_RESULT_UNBOOTSTRAPPED = 3;
+}
+
+enum BootstrapResult {
+  BOOTSTRAP_RESULT_UNSPECIFIED = 0;
+  BOOTSTRAP_RESULT_SUCCESS = 1;
+  BOOTSTRAP_RESULT_ALREADY_BOOTSTRAPPED = 2;
+  BOOTSTRAP_RESULT_INVALID_KEY = 3;
+}
+
+enum VaultState {
+  VAULT_STATE_UNSPECIFIED = 0;
+  VAULT_STATE_UNBOOTSTRAPPED = 1;
+  VAULT_STATE_SEALED = 2;
+  VAULT_STATE_UNSEALED = 3;
+  VAULT_STATE_ERROR = 4;
+}
+
+message SdkClientConnectionRequest {
+  bytes pubkey = 1;
+}
+
+message SdkClientConnectionResponse {
+  bool approved = 1;
+}
+
+message SdkClientConnectionCancel {}
+
+message UserAgentRequest {
+  int32 id = 16;
+  oneof payload {
+    AuthChallengeRequest auth_challenge_request = 1;
+    AuthChallengeSolution auth_challenge_solution = 2;
+    UnsealStart unseal_start = 3;
+    UnsealEncryptedKey unseal_encrypted_key = 4;
+    google.protobuf.Empty query_vault_state = 5;
+    google.protobuf.Empty evm_wallet_create = 6;
+    google.protobuf.Empty evm_wallet_list = 7;
+    arbiter.evm.EvmGrantCreateRequest evm_grant_create = 8;
+    arbiter.evm.EvmGrantDeleteRequest evm_grant_delete = 9;
+    arbiter.evm.EvmGrantListRequest evm_grant_list = 10;
+    SdkClientConnectionResponse sdk_client_connection_response = 11;
+    SdkClientApproveRequest sdk_client_approve = 12;
+    SdkClientRevokeRequest sdk_client_revoke = 13;
+    google.protobuf.Empty sdk_client_list = 14;
+    BootstrapEncryptedKey bootstrap_encrypted_key = 15;
+  }
+}
+message UserAgentResponse {
+  optional int32 id = 16;
+  oneof payload {
+    AuthChallenge auth_challenge = 1;
+    AuthResult auth_result = 2;
+    UnsealStartResponse unseal_start_response = 3;
+    UnsealResult unseal_result = 4;
+    VaultState vault_state = 5;
+    arbiter.evm.WalletCreateResponse evm_wallet_create = 6;
+    arbiter.evm.WalletListResponse evm_wallet_list = 7;
+    arbiter.evm.EvmGrantCreateResponse evm_grant_create = 8;
+    arbiter.evm.EvmGrantDeleteResponse evm_grant_delete = 9;
+    arbiter.evm.EvmGrantListResponse evm_grant_list = 10;
+    SdkClientConnectionResponse sdk_client_connection_response = 11;
+    SdkClientApproveResponse sdk_client_approve_response = 12;
+    SdkClientRevokeResponse sdk_client_revoke_response = 13;
+    SdkClientListResponse sdk_client_list_response = 14;
+    BootstrapResult bootstrap_result = 15;
+  }
+}

server/.cargo/config.toml

@@ -1,2 +0,0 @@
-[env]
-MACOSX_DEPLOYMENT_TARGET = "26.3"

server/.cargo/mutants.toml

@@ -1 +0,0 @@
-test_tool = "nextest"

server/.gitignore

@@ -1,2 +0,0 @@
-mutants.out/
-mutants.out.old/

server/Cargo.toml

@@ -1,171 +1,44 @@
 [workspace]
-members = [
-    "crates/*",
-]
+members = ["crates/*"]
 resolver = "3"
 
+[workspace.lints.clippy]
+disallowed-methods = "deny"
+
 
 [workspace.dependencies]
-alloy = "2.0.4"
-async-trait = "0.1.89"
-base64 = "0.22.1"
-chrono = { version = "0.4.44", features = ["serde"] }
-futures = "0.3.32"
-k256 = { version = "0.13.4", features = ["ecdsa", "pkcs8"] }
-kameo = {git = "https://github.com/hdbg/kameo.git", rev = "17af90e3"}
-kameo_actors = {git = "https://github.com/hdbg/kameo.git", rev = "17af90e3"}
-hmac = "0.13.0"
-miette = { version = "7.6.0", features = ["fancy", "serde"] }
-ml-dsa = { version = "0.1.0-rc.9", features = ["zeroize"] }
-mutants = "0.0.4"
-prost = "0.14.3"
-prost-types = { version = "0.14.3", features = ["chrono"] }
-rand = "0.10.1"
-rcgen = { version = "0.14.7", features = [ "aws_lc_rs",  "pem", "x509-parser", "zeroize" ], default-features = false }
-rstest = "0.26.1"
-rustls = { version = "0.23.40", features = ["aws-lc-rs", "logging", "prefer-post-quantum", "std"], default-features = false }
-rustls-pki-types = "1.14.1"
-sha2 = "0.11"
-smlang = "0.8.0"
-strum = { version = "0.28.0", features = ["derive"] }
-thiserror = "2.0.18"
-tokio = { version = "1.52.1", features = ["full"] }
-tokio-stream = { version = "0.1.18", features = ["full"] }
-tonic = { version = "0.14.5", features = [ "deflate", "gzip", "tls-connect-info", "zstd" ] }
+tonic = { version = "0.14.5", features = [
+    "deflate",
+    "gzip",
+    "tls-connect-info",
+    "zstd",
+] }
 tracing = "0.1.44"
+tokio = { version = "1.50.0", features = ["full"] }
+ed25519-dalek = { version = "3.0.0-pre.6", features = ["rand_core"] }
+chrono = { version = "0.4.44", features = ["serde"] }
+rand = "0.10.0"
+rustls = { version = "0.23.37", features = ["aws-lc-rs"] }
+smlang = "0.8.0"
+miette = { version = "7.6.0", features = ["fancy", "serde"] }
+thiserror = "2.0.18"
+async-trait = "0.1.89"
+futures = "0.3.32"
+tokio-stream = { version = "0.1.18", features = ["full"] }
+kameo = "0.19.2"
+prost-types = { version = "0.14.3", features = ["chrono"] }
 x25519-dalek = { version = "2.0.1", features = ["getrandom"] }
-
-[workspace.lints.rust]
-missing_unsafe_on_extern = "deny"
-unsafe_attr_outside_unsafe = "deny"
-unsafe_op_in_unsafe_fn = "deny"
-unstable_features = "deny"
-
-deprecated_safe_2024 = "warn"
-ffi_unwind_calls = "warn"
-linker_messages = "warn"
-
-elided_lifetimes_in_paths = "warn"
-explicit_outlives_requirements = "warn"
-impl-trait-overcaptures = "warn"
-impl-trait-redundant-captures = "warn"
-redundant_lifetimes = "warn"
-single_use_lifetimes = "warn"
-unused_lifetimes = "warn"
-
-macro_use_extern_crate = "warn"
-redundant_imports = "warn"
-unused_import_braces = "warn"
-unused_macro_rules = "warn"
-unused_qualifications = "warn"
-
-unit_bindings = "warn"
-
-# missing_docs = "warn" # ENABLE BY THE FIRST MAJOR VERSION!!
-unnameable_types = "warn"
-
-[workspace.lints.clippy]
-derive_partial_eq_without_eq = "allow" 
-future_not_send = "allow"
-inconsistent_struct_constructor = "allow"
-inline_always = "allow"
-missing_errors_doc = "allow"
-missing_fields_in_debug = "allow"
-missing_panics_doc = "allow"
-must_use_candidate = "allow"
-needless_pass_by_ref_mut = "allow"
-pub_underscore_fields = "allow"
-redundant_pub_crate = "allow" 
-uninhabited_references = "allow" # safe with unsafe_code = "forbid" and standard uninhabited pattern (match *self {})
-
-# restriction lints
-alloc_instead_of_core = "warn"
-allow_attributes_without_reason = "warn"
-as_conversions = "warn"
-assertions_on_result_states = "warn"
-cfg_not_test = "warn"
-clone_on_ref_ptr = "warn"
-cognitive_complexity = "warn"
-create_dir = "warn"
-dbg_macro = "warn"
-decimal_literal_representation = "warn"
-default_union_representation = "warn"
-deref_by_slicing = "warn"
-disallowed_script_idents = "warn"
-doc_include_without_cfg = "warn"
-empty_drop = "warn"
-empty_enum_variants_with_brackets = "warn"
-empty_structs_with_brackets = "warn"
-exit = "warn"
-filetype_is_file = "warn"
-float_arithmetic = "warn"
-float_cmp_const = "warn"
-fn_to_numeric_cast_any = "warn"
-get_unwrap = "warn"
-if_then_some_else_none = "warn"
-indexing_slicing = "warn"
-infinite_loop = "warn"
-inline_asm_x86_att_syntax = "warn"
-inline_asm_x86_intel_syntax = "warn"
-large_include_file = "warn"
-lossy_float_literal = "warn"
-map_with_unused_argument_over_ranges = "warn"
-mem_forget = "warn"
-missing_assert_message = "warn"
-mixed_read_write_in_expression = "warn"
-modulo_arithmetic = "warn"
-multiple_unsafe_ops_per_block = "warn"
-mutex_atomic = "warn"
-mutex_integer = "warn"
-needless_raw_strings = "warn"
-non_ascii_literal = "warn"
-non_zero_suggestions = "warn"
-pathbuf_init_then_push = "warn"
-pointer_format = "warn"
-precedence_bits = "warn"
-pub_without_shorthand = "warn"
-rc_buffer = "warn"
-rc_mutex = "warn"
-redundant_test_prefix = "warn"
-redundant_type_annotations = "warn"
-ref_patterns = "warn"
-renamed_function_params = "warn"
-rest_pat_in_fully_bound_structs = "warn"
-return_and_then = "warn"
-semicolon_inside_block = "warn"
-str_to_string = "warn"
-string_add = "warn"
-string_lit_chars_any = "warn"
-string_slice = "warn"
-suspicious_xor_used_as_pow = "warn"
-try_err = "warn"
-undocumented_unsafe_blocks = "warn"
-uninlined_format_args = "warn"
-unnecessary_safety_comment = "warn"
-unnecessary_safety_doc = "warn"
-unnecessary_self_imports = "warn"
-unneeded_field_pattern = "warn"
-unused_result_ok = "warn"
-verbose_file_reads = "warn"
-
-# cargo lints
-negative_feature_names = "warn"
-redundant_feature_names = "warn"
-wildcard_dependencies = "warn"
-
-# ENABLE BY THE FIRST MAJOR VERSION!!
-# todo = "warn"
-# unimplemented = "warn"
-# panic = "warn"
-# panic_in_result_fn = "warn"
-# 
-# cargo_common_metadata = "warn"
-# multiple_crate_versions = "warn" # a controversial option since it's really difficult to maintain
-
-disallowed_methods = "deny"
-
-nursery = { level = "warn", priority = -1 }
-pedantic = { level = "warn", priority = -1 }
-
-type_repetition_in_bounds = "allow"   # sometimes, it's better for readability this way
-unused_async_trait_impl = "allow"
+rstest = "0.26.1"
+rustls-pki-types = "1.14.0"
+alloy = "1.7.3"
+rcgen = { version = "0.14.7", features = [
+    "aws_lc_rs",
+    "pem",
+    "x509-parser",
+    "zeroize",
+], default-features = false }
+k256 = { version = "0.13.4", features = ["ecdsa", "pkcs8"] }
+rsa = { version = "0.9", features = ["sha2"] }
+sha2 = "0.10"
+spki = "0.7"
+terrors = { version = "0.5", git = "https://github.com/CleverWild/terrors" }

server/clippy.toml

@@ -7,24 +7,3 @@ disallowed-methods = [
     { path = "rsa::traits::Decryptor::decrypt", reason = "RSA decryption is forbidden (RUSTSEC-2023-0071 Marvin Attack). This blocks decrypt() on rsa::{pkcs1v15,oaep}::DecryptingKey." },
     { path = "rsa::traits::RandomizedDecryptor::decrypt_with_rng", reason = "RSA decryption is forbidden (RUSTSEC-2023-0071 Marvin Attack). This blocks decrypt_with_rng() on rsa::{pkcs1v15,oaep}::DecryptingKey." },
 ]
-
-allow-indexing-slicing-in-tests = true
-allow-panic-in-tests = true
-check-inconsistent-struct-field-initializers = true
-suppress-restriction-lint-in-const = true
-allow-renamed-params-for = [
-    "core::convert::From",
-    "core::convert::TryFrom",
-    "core::str::FromStr",
-    "kameo::actor::Actor",
-]
-
-module-items-ordered-within-groupings = ["UPPER_SNAKE_CASE"]
-source-item-ordering = ["enum"]
-trait-assoc-item-kinds-order = [
-    "const",
-    "type",
-    "fn",
-] # community tested standard
-
-too-many-lines-threshold = 150

server/crates/arbiter-client/Cargo.toml

@@ -13,17 +13,15 @@ evm = ["dep:alloy"]
 
 [dependencies]
 arbiter-proto.path = "../arbiter-proto"
-arbiter-crypto.path = "../arbiter-crypto"
 alloy = { workspace = true, optional = true }
 tonic.workspace = true
 tonic.features = ["tls-aws-lc"]
 tokio.workspace = true
 tokio-stream.workspace = true
+ed25519-dalek.workspace = true
 thiserror.workspace = true
 http = "1.4.0"
-rustls-webpki = { version = "0.103.13", features = ["aws-lc-rs"] }
+rustls-webpki = { version = "0.103.10", features = ["aws-lc-rs"] }
 async-trait.workspace = true
-chrono.workspace = true
-
-[lib]
-doctest = false
+rand.workspace = true
+terrors.workspace = true

server/crates/arbiter-client/src/auth.rs

@@ -1,159 +1,102 @@
-use crate::{
-    storage::StorageError,
-    transport::{ClientTransport, next_request_id},
-};
-use arbiter_crypto::authn::{self, SigningContext, SigningKey};
 use arbiter_proto::{
-    ClientMetadata,
-    proto::{
-        client::{
-            ClientRequest,
-            auth::{
-                self as proto_auth, AuthChallenge, AuthChallengeRequest, AuthChallengeSolution,
-                AuthResult, request::Payload as AuthRequestPayload,
-                response::Payload as AuthResponsePayload,
-            },
+    format_challenge,
+    proto::client::{
+        AuthChallengeRequest, AuthChallengeSolution, AuthResult, ClientRequest,
         client_request::Payload as ClientRequestPayload,
         client_response::Payload as ClientResponsePayload,
     },
-        shared::ClientInfo as ProtoClientInfo,
-    },
 };
+use ed25519_dalek::Signer as _;
+use terrors::OneOf;
 
-use chrono::DateTime;
-
-#[derive(Debug, thiserror::Error)]
-pub enum AuthError {
-    #[error("Server sent invalid auth challenge")]
-    InvalidChallenge,
-    #[error("Client approval denied by Operator")]
-    ApprovalDenied,
-    #[error("Auth challenge was not returned by server")]
-    MissingAuthChallenge,
-
-    #[error("No Operators online to approve client")]
-    NoOperatorsOnline,
-
-    #[error("Signing key storage error")]
-    Storage(#[from] StorageError),
-
-    #[error("Unexpected auth response payload")]
-    UnexpectedAuthResponse,
-}
-
-fn map_auth_result(code: i32) -> AuthError {
-    match AuthResult::try_from(code).unwrap_or(AuthResult::Unspecified) {
-        AuthResult::ApprovalDenied => AuthError::ApprovalDenied,
-        AuthResult::NoOperatorsOnline => AuthError::NoOperatorsOnline,
-        AuthResult::Unspecified
-        | AuthResult::Success
-        | AuthResult::InvalidKey
-        | AuthResult::InvalidSignature
-        | AuthResult::Internal => AuthError::UnexpectedAuthResponse,
-    }
-}
+use crate::{
+    errors::{
+        ConnectError, MissingAuthChallengeError, UnexpectedAuthResponseError, map_auth_code_error,
+    },
+    transport::{ClientTransport, next_request_id},
+};
 
 async fn send_auth_challenge_request(
     transport: &mut ClientTransport,
-    metadata: ClientMetadata,
-    key: &SigningKey,
-) -> Result<(), AuthError> {
+    key: &ed25519_dalek::SigningKey,
+) -> std::result::Result<(), ConnectError> {
     transport
         .send(ClientRequest {
             request_id: next_request_id(),
-            payload: Some(ClientRequestPayload::Auth(proto_auth::Request {
-                payload: Some(AuthRequestPayload::ChallengeRequest(AuthChallengeRequest {
-                    pubkey: key.public_key().to_bytes(),
-                    client_info: Some(ProtoClientInfo {
-                        name: metadata.name,
-                        description: metadata.description,
-                        version: metadata.version,
-                    }),
-                })),
-            })),
+            payload: Some(ClientRequestPayload::AuthChallengeRequest(
+                AuthChallengeRequest {
+                    pubkey: key.verifying_key().to_bytes().to_vec(),
+                },
+            )),
         })
         .await
-        .map_err(|_| AuthError::UnexpectedAuthResponse)
+        .map_err(|_| OneOf::new(UnexpectedAuthResponseError))
 }
 
 async fn receive_auth_challenge(
     transport: &mut ClientTransport,
-) -> Result<AuthChallenge, AuthError> {
+) -> std::result::Result<arbiter_proto::proto::client::AuthChallenge, ConnectError> {
     let response = transport
         .recv()
         .await
-        .map_err(|_| AuthError::MissingAuthChallenge)?;
+        .map_err(|_| OneOf::new(MissingAuthChallengeError))?;
 
-    let payload = response.payload.ok_or(AuthError::MissingAuthChallenge)?;
+    let payload = response
+        .payload
+        .ok_or_else(|| OneOf::new(MissingAuthChallengeError))?;
     match payload {
-        ClientResponsePayload::Auth(response) => match response.payload {
-            Some(AuthResponsePayload::Challenge(challenge)) => Ok(challenge),
-            Some(AuthResponsePayload::Result(result)) => Err(map_auth_result(result)),
-            None => Err(AuthError::MissingAuthChallenge),
-        },
-        _ => Err(AuthError::UnexpectedAuthResponse),
+        ClientResponsePayload::AuthChallenge(challenge) => Ok(challenge),
+        ClientResponsePayload::AuthResult(result) => Err(map_auth_code_error(result)),
+        _ => Err(OneOf::new(UnexpectedAuthResponseError)),
     }
 }
 
 async fn send_auth_challenge_solution(
     transport: &mut ClientTransport,
-    key: &SigningKey,
-    challenge: AuthChallenge,
-) -> Result<(), AuthError> {
-    let timestamp = DateTime::from_timestamp_nanos(challenge.timestamp_nanos as i64);
-    let challenge = authn::AuthChallenge {
-        nonce: *challenge
-            .random
-            .as_array()
-            .ok_or(AuthError::InvalidChallenge)?,
-        timestamp,
-    };
-    let challenge_payload: Vec<u8> = challenge.format();
-    let signature = key
-        .sign_message(&challenge_payload, SigningContext::Client)
-        .map_err(|_| AuthError::UnexpectedAuthResponse)?
-        .to_bytes();
+    key: &ed25519_dalek::SigningKey,
+    challenge: arbiter_proto::proto::client::AuthChallenge,
+) -> std::result::Result<(), ConnectError> {
+    let challenge_payload = format_challenge(challenge.nonce, &challenge.pubkey);
+    let signature = key.sign(&challenge_payload).to_bytes().to_vec();
 
     transport
         .send(ClientRequest {
             request_id: next_request_id(),
-            payload: Some(ClientRequestPayload::Auth(proto_auth::Request {
-                payload: Some(AuthRequestPayload::ChallengeSolution(
+            payload: Some(ClientRequestPayload::AuthChallengeSolution(
                 AuthChallengeSolution { signature },
             )),
-            })),
         })
         .await
-        .map_err(|_| AuthError::UnexpectedAuthResponse)
+        .map_err(|_| OneOf::new(UnexpectedAuthResponseError))
 }
 
-async fn receive_auth_confirmation(transport: &mut ClientTransport) -> Result<(), AuthError> {
+async fn receive_auth_confirmation(
+    transport: &mut ClientTransport,
+) -> std::result::Result<(), ConnectError> {
     let response = transport
         .recv()
         .await
-        .map_err(|_| AuthError::UnexpectedAuthResponse)?;
+        .map_err(|_| OneOf::new(UnexpectedAuthResponseError))?;
 
-    let payload = response.payload.ok_or(AuthError::UnexpectedAuthResponse)?;
+    let payload = response
+        .payload
+        .ok_or_else(|| OneOf::new(UnexpectedAuthResponseError))?;
     match payload {
-        ClientResponsePayload::Auth(response) => match response.payload {
-            Some(AuthResponsePayload::Result(result))
+        ClientResponsePayload::AuthResult(result)
             if AuthResult::try_from(result).ok() == Some(AuthResult::Success) =>
         {
             Ok(())
         }
-            Some(AuthResponsePayload::Result(result)) => Err(map_auth_result(result)),
-            _ => Err(AuthError::UnexpectedAuthResponse),
-        },
-        _ => Err(AuthError::UnexpectedAuthResponse),
+        ClientResponsePayload::AuthResult(result) => Err(map_auth_code_error(result)),
+        _ => Err(OneOf::new(UnexpectedAuthResponseError)),
     }
 }
 
-pub async fn authenticate(
+pub(crate) async fn authenticate(
     transport: &mut ClientTransport,
-    metadata: ClientMetadata,
-    key: &SigningKey,
-) -> Result<(), AuthError> {
-    send_auth_challenge_request(transport, metadata, key).await?;
+    key: &ed25519_dalek::SigningKey,
+) -> std::result::Result<(), ConnectError> {
+    send_auth_challenge_request(transport, key).await?;
     let challenge = receive_auth_challenge(transport).await?;
     send_auth_challenge_solution(transport, key, challenge).await?;
     receive_auth_confirmation(transport).await

server/crates/arbiter-client/src/bin/test_connect.rs

@@ -1,44 +0,0 @@
-use arbiter_client::ArbiterClient;
-use arbiter_proto::{ClientMetadata, url::ArbiterUrl};
-
-use std::io::{self, Write};
-
-#[tokio::main]
-async fn main() {
-    println!("Testing connection to Arbiter server...");
-    print!("Enter ArbiterUrl: ");
-    let _ = io::stdout().flush();
-
-    let mut input = String::new();
-    if let Err(err) = io::stdin().read_line(&mut input) {
-        eprintln!("Failed to read input: {err}");
-        return;
-    }
-
-    let input = input.trim();
-    if input.is_empty() {
-        eprintln!("ArbiterUrl cannot be empty");
-        return;
-    }
-
-    let url = match ArbiterUrl::try_from(input) {
-        Ok(url) => url,
-        Err(err) => {
-            eprintln!("Invalid ArbiterUrl: {err}");
-            return;
-        }
-    };
-
-    println!("{url:#?}");
-
-    let metadata = ClientMetadata {
-        name: "arbiter-client test_connect".to_owned(),
-        description: Some("Manual connection smoke test".to_owned()),
-        version: Some(env!("CARGO_PKG_VERSION").to_owned()),
-    };
-
-    match ArbiterClient::connect(url, metadata).await {
-        Ok(_) => println!("Connected and authenticated successfully."),
-        Err(err) => eprintln!("Failed to connect: {err:#?}"),
-    }
-}

server/crates/arbiter-client/src/client.rs

@@ -1,92 +1,73 @@
-#[cfg(feature = "evm")]
-use crate::wallets::evm::ArbiterEvmWallet;
-use crate::{
-    StorageError,
-    auth::{AuthError, authenticate},
-    storage::{FileSigningKeyStorage, SigningKeyStorage},
-    transport::{BUFFER_LENGTH, ClientTransport},
-};
-use arbiter_crypto::authn::SigningKey;
-use arbiter_proto::{
-    ClientMetadata, proto::arbiter_service_client::ArbiterServiceClient, url::ArbiterUrl,
-};
-
+use arbiter_proto::{proto::arbiter_service_client::ArbiterServiceClient, url::ArbiterUrl};
 use std::sync::Arc;
+use terrors::{Broaden as _, OneOf};
 use tokio::sync::{Mutex, mpsc};
 use tokio_stream::wrappers::ReceiverStream;
 use tonic::transport::ClientTlsConfig;
 
-#[derive(Debug, thiserror::Error)]
-pub enum ArbiterClientError {
-    #[error("Authentication error")]
-    Authentication(#[from] AuthError),
+use crate::{
+    auth::authenticate,
+    errors::ConnectError,
+    storage::{FileSigningKeyStorage, SigningKeyStorage},
+    transport::{BUFFER_LENGTH, ClientTransport},
+};
 
-    #[error("Could not establish connection")]
-    Connection(#[from] tonic::transport::Error),
+#[cfg(feature = "evm")]
+use crate::errors::{ClientConnectionClosedError, ClientError};
 
-    #[error("gRPC error")]
-    Grpc(#[from] tonic::Status),
-
-    #[error("Invalid CA certificate")]
-    InvalidCaCert(#[from] webpki::Error),
-
-    #[error("Invalid server URI")]
-    InvalidUri(#[from] http::uri::InvalidUri),
-
-    #[error("Storage error")]
-    Storage(#[from] StorageError),
-}
+#[cfg(feature = "evm")]
+use crate::wallets::evm::ArbiterEvmWallet;
 
 pub struct ArbiterClient {
-    #[expect(
-        dead_code,
-        reason = "transport will be used in future methods for sending requests and receiving responses"
-    )]
+    #[allow(dead_code)]
     transport: Arc<Mutex<ClientTransport>>,
 }
 
 impl ArbiterClient {
-    pub async fn connect(
-        url: ArbiterUrl,
-        metadata: ClientMetadata,
-    ) -> Result<Self, ArbiterClientError> {
-        let storage = FileSigningKeyStorage::from_default_location()?;
-        Self::connect_with_storage(url, metadata, &storage).await
+    pub async fn connect(url: ArbiterUrl) -> Result<Self, ConnectError> {
+        let storage = FileSigningKeyStorage::from_default_location().broaden()?;
+        Self::connect_with_storage(url, &storage).await
     }
 
     pub async fn connect_with_storage<S: SigningKeyStorage>(
         url: ArbiterUrl,
-        metadata: ClientMetadata,
         storage: &S,
-    ) -> Result<Self, ArbiterClientError> {
-        let key = storage.load_or_create()?;
-        Self::connect_with_key(url, metadata, key).await
+    ) -> Result<Self, ConnectError> {
+        let key = storage.load_or_create().broaden()?;
+        Self::connect_with_key(url, key).await
     }
 
     pub async fn connect_with_key(
         url: ArbiterUrl,
-        metadata: ClientMetadata,
-        key: SigningKey,
-    ) -> Result<Self, ArbiterClientError> {
-        let anchor = webpki::anchor_from_trusted_cert(&url.ca_cert)?.to_owned();
+        key: ed25519_dalek::SigningKey,
+    ) -> Result<Self, ConnectError> {
+        let anchor = webpki::anchor_from_trusted_cert(&url.ca_cert)
+            .map_err(OneOf::new)?
+            .to_owned();
         let tls = ClientTlsConfig::new().trust_anchor(anchor);
 
-        let channel =
-            tonic::transport::Channel::from_shared(format!("https://{}:{}", url.host, url.port))?
-                .tls_config(tls)?
+        let channel = tonic::transport::Channel::from_shared(format!("{}:{}", url.host, url.port))
+            .map_err(OneOf::new)?
+            .tls_config(tls)
+            .map_err(OneOf::new)?
             .connect()
-                .await?;
+            .await
+            .map_err(OneOf::new)?;
 
         let mut client = ArbiterServiceClient::new(channel);
         let (tx, rx) = mpsc::channel(BUFFER_LENGTH);
-        let response_stream = client.client(ReceiverStream::new(rx)).await?.into_inner();
+        let response_stream = client
+            .client(ReceiverStream::new(rx))
+            .await
+            .map_err(OneOf::new)?
+            .into_inner();
 
         let mut transport = ClientTransport {
             sender: tx,
             receiver: response_stream,
         };
 
-        authenticate(&mut transport, metadata, &key).await?;
+        authenticate(&mut transport, &key).await?;
 
         Ok(Self {
             transport: Arc::new(Mutex::new(transport)),
@@ -94,8 +75,8 @@ impl ArbiterClient {
     }
 
     #[cfg(feature = "evm")]
-    #[expect(clippy::unused_async, reason = "false positive")]
-    pub async fn evm_wallets(&self) -> Result<Vec<ArbiterEvmWallet>, ArbiterClientError> {
-        todo!("fetch EVM wallet list from server")
+    pub async fn evm_wallets(&self) -> Result<Vec<ArbiterEvmWallet>, ClientError> {
+        let _ = &self.transport;
+        Err(OneOf::new(ClientConnectionClosedError))
     }
 }

server/crates/arbiter-client/src/errors.rs

@@ -0,0 +1,127 @@
+use terrors::OneOf;
+use thiserror::Error;
+
+#[cfg(feature = "evm")]
+use alloy::{primitives::ChainId, signers::Error as AlloySignerError};
+
+pub type StorageError = OneOf<(std::io::Error, InvalidKeyLengthError)>;
+
+pub type ConnectError = OneOf<(
+    tonic::transport::Error,
+    http::uri::InvalidUri,
+    webpki::Error,
+    tonic::Status,
+    MissingAuthChallengeError,
+    ApprovalDeniedError,
+    NoUserAgentsOnlineError,
+    UnexpectedAuthResponseError,
+    std::io::Error,
+    InvalidKeyLengthError,
+)>;
+
+pub type ClientError = OneOf<(tonic::Status, ClientConnectionClosedError)>;
+
+pub(crate) type ClientTransportError =
+    OneOf<(TransportChannelClosedError, TransportConnectionClosedError)>;
+
+#[cfg(feature = "evm")]
+pub(crate) type EvmWalletError = OneOf<(
+    EvmChainIdMismatchError,
+    EvmHashSigningUnsupportedError,
+    EvmTransactionSigningUnsupportedError,
+)>;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("Invalid signing key length in storage: expected {expected} bytes, got {actual} bytes")]
+pub struct InvalidKeyLengthError {
+    pub expected: usize,
+    pub actual: usize,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("Auth challenge was not returned by server")]
+pub struct MissingAuthChallengeError;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("Client approval denied by User Agent")]
+pub struct ApprovalDeniedError;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("No User Agents online to approve client")]
+pub struct NoUserAgentsOnlineError;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("Unexpected auth response payload")]
+pub struct UnexpectedAuthResponseError;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("Connection closed by server")]
+pub struct ClientConnectionClosedError;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("Transport channel closed")]
+pub struct TransportChannelClosedError;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("Connection closed by server")]
+pub struct TransportConnectionClosedError;
+
+#[cfg(feature = "evm")]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("Transaction chain id mismatch: signer {signer}, tx {tx}")]
+pub struct EvmChainIdMismatchError {
+    pub signer: ChainId,
+    pub tx: ChainId,
+}
+
+#[cfg(feature = "evm")]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("hash-only signing is not supported for ArbiterEvmWallet; use transaction signing")]
+pub struct EvmHashSigningUnsupportedError;
+
+#[cfg(feature = "evm")]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)]
+#[error("transaction signing is not supported by current arbiter.client protocol")]
+pub struct EvmTransactionSigningUnsupportedError;
+
+pub(crate) fn map_auth_code_error(code: i32) -> ConnectError {
+    use arbiter_proto::proto::client::AuthResult;
+
+    match AuthResult::try_from(code).unwrap_or(AuthResult::Unspecified) {
+        AuthResult::ApprovalDenied => OneOf::new(ApprovalDeniedError),
+        AuthResult::NoUserAgentsOnline => OneOf::new(NoUserAgentsOnlineError),
+        AuthResult::Unspecified
+        | AuthResult::Success
+        | AuthResult::InvalidKey
+        | AuthResult::InvalidSignature
+        | AuthResult::Internal => OneOf::new(UnexpectedAuthResponseError),
+    }
+}
+
+#[cfg(feature = "evm")]
+impl From<EvmChainIdMismatchError> for AlloySignerError {
+    fn from(value: EvmChainIdMismatchError) -> Self {
+        AlloySignerError::TransactionChainIdMismatch {
+            signer: value.signer,
+            tx: value.tx,
+        }
+    }
+}
+
+#[cfg(feature = "evm")]
+impl From<EvmHashSigningUnsupportedError> for AlloySignerError {
+    fn from(_value: EvmHashSigningUnsupportedError) -> Self {
+        AlloySignerError::other(
+            "hash-only signing is not supported for ArbiterEvmWallet; use transaction signing",
+        )
+    }
+}
+
+#[cfg(feature = "evm")]
+impl From<EvmTransactionSigningUnsupportedError> for AlloySignerError {
+    fn from(_value: EvmTransactionSigningUnsupportedError) -> Self {
+        AlloySignerError::other(
+            "transaction signing is not supported by current arbiter.client protocol",
+        )
+    }
+}

server/crates/arbiter-client/src/lib.rs

@@ -1,12 +1,13 @@
 mod auth;
 mod client;
+mod errors;
 mod storage;
 mod transport;
 pub mod wallets;
 
-pub use auth::AuthError;
-pub use client::{ArbiterClient, ArbiterClientError};
-pub use storage::{FileSigningKeyStorage, SigningKeyStorage, StorageError};
+pub use client::ArbiterClient;
+pub use errors::{ClientError, ConnectError, StorageError};
+pub use storage::{FileSigningKeyStorage, SigningKeyStorage};
 
 #[cfg(feature = "evm")]
-pub use wallets::evm::{ArbiterEvmSignTransactionError, ArbiterEvmWallet};
+pub use wallets::evm::ArbiterEvmWallet;

server/crates/arbiter-client/src/storage.rs

@@ -1,19 +1,11 @@
-use arbiter_crypto::authn::SigningKey;
 use arbiter_proto::home_path;
-
 use std::path::{Path, PathBuf};
+use terrors::OneOf;
 
-#[derive(Debug, thiserror::Error)]
-pub enum StorageError {
-    #[error("Invalid signing key length in storage: expected {expected} bytes, got {actual} bytes")]
-    InvalidKeyLength { expected: usize, actual: usize },
-
-    #[error("I/O error")]
-    Io(#[from] std::io::Error),
-}
+use crate::errors::{InvalidKeyLengthError, StorageError};
 
 pub trait SigningKeyStorage {
-    fn load_or_create(&self) -> Result<SigningKey, StorageError>;
+    fn load_or_create(&self) -> std::result::Result<ed25519_dalek::SigningKey, StorageError>;
 }
 
 #[derive(Debug, Clone)]
@@ -22,41 +14,44 @@ pub struct FileSigningKeyStorage {
 }
 
 impl FileSigningKeyStorage {
-    pub const DEFAULT_FILE_NAME: &str = "sdk_client_ml_dsa.key";
+    pub const DEFAULT_FILE_NAME: &str = "sdk_client_ed25519.key";
 
     pub fn new(path: impl Into<PathBuf>) -> Self {
         Self { path: path.into() }
     }
 
-    pub fn from_default_location() -> Result<Self, StorageError> {
-        Ok(Self::new(home_path()?.join(Self::DEFAULT_FILE_NAME)))
+    pub fn from_default_location() -> std::result::Result<Self, StorageError> {
+        Ok(Self::new(
+            home_path()
+                .map_err(OneOf::new)?
+                .join(Self::DEFAULT_FILE_NAME),
+        ))
     }
 
-    fn read_key(path: &Path) -> Result<SigningKey, StorageError> {
-        let bytes = std::fs::read(path)?;
-        let raw: [u8; 32] =
-            bytes
-                .try_into()
-                .map_err(|v: Vec<u8>| StorageError::InvalidKeyLength {
+    fn read_key(path: &Path) -> std::result::Result<ed25519_dalek::SigningKey, StorageError> {
+        let bytes = std::fs::read(path).map_err(OneOf::new)?;
+        let raw: [u8; 32] = bytes.try_into().map_err(|v: Vec<u8>| {
+            OneOf::new(InvalidKeyLengthError {
                 expected: 32,
                 actual: v.len(),
+            })
         })?;
-        Ok(SigningKey::from_seed(raw))
+        Ok(ed25519_dalek::SigningKey::from_bytes(&raw))
     }
 }
 
 impl SigningKeyStorage for FileSigningKeyStorage {
-    fn load_or_create(&self) -> Result<SigningKey, StorageError> {
+    fn load_or_create(&self) -> std::result::Result<ed25519_dalek::SigningKey, StorageError> {
         if let Some(parent) = self.path.parent() {
-            std::fs::create_dir_all(parent)?;
+            std::fs::create_dir_all(parent).map_err(OneOf::new)?;
         }
 
         if self.path.exists() {
             return Self::read_key(&self.path);
         }
 
-        let key = SigningKey::generate();
-        let raw_key = key.to_seed();
+        let key = ed25519_dalek::SigningKey::generate(&mut rand::rng());
+        let raw_key = key.to_bytes();
 
         // Use create_new to prevent accidental overwrite if another process creates the key first.
         match std::fs::OpenOptions::new()
@@ -66,20 +61,21 @@ impl SigningKeyStorage for FileSigningKeyStorage {
         {
             Ok(mut file) => {
                 use std::io::Write as _;
-                file.write_all(&raw_key)?;
+                file.write_all(&raw_key).map_err(OneOf::new)?;
                 Ok(key)
             }
             Err(err) if err.kind() == std::io::ErrorKind::AlreadyExists => {
                 Self::read_key(&self.path)
             }
-            Err(err) => Err(StorageError::Io(err)),
+            Err(err) => Err(OneOf::new(err)),
         }
     }
 }
 
 #[cfg(test)]
 mod tests {
-    use super::{FileSigningKeyStorage, SigningKeyStorage, StorageError};
+    use super::{FileSigningKeyStorage, SigningKeyStorage};
+    use crate::errors::InvalidKeyLengthError;
 
     fn unique_temp_key_path() -> std::path::PathBuf {
         let nanos = std::time::SystemTime::now()
@@ -105,7 +101,7 @@ mod tests {
             .load_or_create()
             .expect("second load_or_create should read same key");
 
-        assert_eq!(key_a.to_seed(), key_b.to_seed());
+        assert_eq!(key_a.to_bytes(), key_b.to_bytes());
         assert!(path.exists());
 
         std::fs::remove_file(path).expect("temp key file should be removable");
@@ -121,12 +117,12 @@ mod tests {
             .load_or_create()
             .expect_err("storage should reject non-32-byte key file");
 
-        match err {
-            StorageError::InvalidKeyLength { expected, actual } => {
-                assert_eq!(expected, 32);
-                assert_eq!(actual, 31);
+        match err.narrow::<InvalidKeyLengthError, _>() {
+            Ok(invalid_len) => {
+                assert_eq!(invalid_len.expected, 32);
+                assert_eq!(invalid_len.actual, 31);
             }
-            other @ StorageError::Io(_) => panic!("unexpected error: {other:?}"),
+            Err(other) => panic!("unexpected io error: {other:?}"),
         }
 
         std::fs::remove_file(path).expect("temp key file should be removable");

server/crates/arbiter-client/src/transport.rs

@@ -1,41 +1,42 @@
 use arbiter_proto::proto::client::{ClientRequest, ClientResponse};
-
 use std::sync::atomic::{AtomicI32, Ordering};
+use terrors::OneOf;
 use tokio::sync::mpsc;
 
-pub const BUFFER_LENGTH: usize = 16;
+use crate::errors::{
+    ClientTransportError, TransportChannelClosedError, TransportConnectionClosedError,
+};
+
+pub(crate) const BUFFER_LENGTH: usize = 16;
 static NEXT_REQUEST_ID: AtomicI32 = AtomicI32::new(1);
 
-pub fn next_request_id() -> i32 {
+pub(crate) fn next_request_id() -> i32 {
     NEXT_REQUEST_ID.fetch_add(1, Ordering::Relaxed)
 }
 
-#[derive(Debug, thiserror::Error)]
-pub enum ClientSignError {
-    #[error("Transport channel closed")]
-    ChannelClosed,
-
-    #[error("Connection closed by server")]
-    ConnectionClosed,
-}
-
-pub struct ClientTransport {
+pub(crate) struct ClientTransport {
     pub(crate) sender: mpsc::Sender<ClientRequest>,
     pub(crate) receiver: tonic::Streaming<ClientResponse>,
 }
 
 impl ClientTransport {
-    pub(crate) async fn send(&mut self, request: ClientRequest) -> Result<(), ClientSignError> {
+    pub(crate) async fn send(
+        &mut self,
+        request: ClientRequest,
+    ) -> std::result::Result<(), ClientTransportError> {
         self.sender
             .send(request)
             .await
-            .map_err(|_| ClientSignError::ChannelClosed)
+            .map_err(|_| OneOf::new(TransportChannelClosedError))
     }
 
-    pub(crate) async fn recv(&mut self) -> Result<ClientResponse, ClientSignError> {
+    pub(crate) async fn recv(
+        &mut self,
+    ) -> std::result::Result<ClientResponse, ClientTransportError> {
         match self.receiver.message().await {
             Ok(Some(resp)) => Ok(resp),
-            Ok(None) | Err(_) => Err(ClientSignError::ConnectionClosed),
+            Ok(None) => Err(OneOf::new(TransportConnectionClosedError)),
+            Err(_) => Err(OneOf::new(TransportConnectionClosedError)),
         }
     }
 }

server/crates/arbiter-client/src/wallets/evm.rs

@@ -1,55 +1,21 @@
-use crate::transport::{ClientTransport, next_request_id};
-use arbiter_proto::proto::{
-    client::{
-        ClientRequest,
-        client_request::Payload as ClientRequestPayload,
-        client_response::Payload as ClientResponsePayload,
-        evm::{
-            self as proto_evm, request::Payload as EvmRequestPayload,
-            response::Payload as EvmResponsePayload,
-        },
-    },
-    evm::{
-        EvmSignTransactionRequest,
-        evm_sign_transaction_response::Result as EvmSignTransactionResult,
-    },
-    shared::evm::TransactionEvalError,
-};
-
 use alloy::{
     consensus::SignableTransaction,
     network::TxSigner,
     primitives::{Address, B256, ChainId, Signature},
-    signers::{Error, Result, Signer},
+    signers::{Result, Signer},
 };
 use async_trait::async_trait;
 use std::sync::Arc;
+use terrors::OneOf;
 use tokio::sync::Mutex;
 
-/// A typed error payload returned by [`ArbiterEvmWallet`] transaction signing.
-///
-/// This is wrapped into `alloy::signers::Error::Other`, so consumers can downcast by [`TryFrom`] and
-/// interpret the concrete policy evaluation failure instead of parsing strings.
-#[derive(Debug, thiserror::Error)]
-#[non_exhaustive]
-pub enum ArbiterEvmSignTransactionError {
-    #[error("transaction rejected by policy: {0:?}")]
-    PolicyEval(TransactionEvalError),
-}
-
-impl<'a> TryFrom<&'a Error> for &'a ArbiterEvmSignTransactionError {
-    type Error = ();
-
-    fn try_from(value: &'a Error) -> Result<Self, Self::Error> {
-        if let Error::Other(inner) = value
-            && let Some(eval_error) = inner.downcast_ref()
-        {
-            Ok(eval_error)
-        } else {
-            Err(())
-        }
-    }
-}
+use crate::{
+    errors::{
+        EvmChainIdMismatchError, EvmHashSigningUnsupportedError,
+        EvmTransactionSigningUnsupportedError, EvmWalletError,
+    },
+    transport::ClientTransport,
+};
 
 pub struct ArbiterEvmWallet {
     transport: Arc<Mutex<ClientTransport>>,
@@ -58,11 +24,8 @@ pub struct ArbiterEvmWallet {
 }
 
 impl ArbiterEvmWallet {
-    #[expect(
-        dead_code,
-        reason = "new will be used in future methods for creating wallets with different parameters"
-    )]
-    pub(crate) const fn new(transport: Arc<Mutex<ClientTransport>>, address: Address) -> Self {
+    #[allow(dead_code)]
+    pub(crate) fn new(transport: Arc<Mutex<ClientTransport>>, address: Address) -> Self {
         Self {
             transport,
             address,
@@ -70,24 +33,26 @@ impl ArbiterEvmWallet {
         }
     }
 
-    pub const fn address(&self) -> Address {
+    pub fn address(&self) -> Address {
         self.address
     }
 
-    #[must_use]
-    pub const fn with_chain_id(mut self, chain_id: ChainId) -> Self {
+    pub fn with_chain_id(mut self, chain_id: ChainId) -> Self {
         self.chain_id = Some(chain_id);
         self
     }
 
-    fn validate_chain_id(&self, tx: &mut dyn SignableTransaction<Signature>) -> Result<()> {
+    fn validate_chain_id(
+        &self,
+        tx: &mut dyn SignableTransaction<Signature>,
+    ) -> std::result::Result<(), EvmWalletError> {
         if let Some(chain_id) = self.chain_id
             && !tx.set_chain_id_checked(chain_id)
         {
-            return Err(Error::TransactionChainIdMismatch {
+            return Err(OneOf::new(EvmChainIdMismatchError {
                 signer: chain_id,
                 tx: tx.chain_id().unwrap(),
-            });
+            }));
         }
 
         Ok(())
@@ -97,9 +62,7 @@ impl ArbiterEvmWallet {
 #[async_trait]
 impl Signer for ArbiterEvmWallet {
     async fn sign_hash(&self, _hash: &B256) -> Result<Signature> {
-        Err(Error::other(
-            "hash-only signing is not supported for ArbiterEvmWallet; use transaction signing",
-        ))
+        Err(EvmWalletError::new(EvmHashSigningUnsupportedError).into())
     }
 
     fn address(&self) -> Address {
@@ -125,73 +88,10 @@ impl TxSigner<Signature> for ArbiterEvmWallet {
         &self,
         tx: &mut dyn SignableTransaction<Signature>,
     ) -> Result<Signature> {
-        self.validate_chain_id(tx)?;
+        let _transport = self.transport.lock().await;
+        self.validate_chain_id(tx)
+            .map_err(OneOf::into::<alloy::signers::Error>)?;
 
-        let mut transport = self.transport.lock().await;
-        let request_id = next_request_id();
-        let rlp_transaction = tx.encoded_for_signing();
-
-        transport
-            .send(ClientRequest {
-                request_id,
-                payload: Some(ClientRequestPayload::Evm(proto_evm::Request {
-                    payload: Some(EvmRequestPayload::SignTransaction(
-                        EvmSignTransactionRequest {
-                            wallet_address: self.address.to_vec(),
-                            rlp_transaction,
-                        },
-                    )),
-                })),
-            })
-            .await
-            .map_err(|_| Error::other("failed to send evm sign transaction request"))?;
-
-        let response = transport
-            .recv()
-            .await
-            .map_err(|_| Error::other("failed to receive evm sign transaction response"))?;
-        drop(transport);
-
-        if response.request_id != Some(request_id) {
-            return Err(Error::other(
-                "received mismatched response id for evm sign transaction",
-            ));
-        }
-
-        let payload = response
-            .payload
-            .ok_or_else(|| Error::other("missing evm sign transaction response payload"))?;
-
-        let ClientResponsePayload::Evm(proto_evm::Response {
-            payload: Some(payload),
-        }) = payload
-        else {
-            return Err(Error::other(
-                "unexpected response payload for evm sign transaction request",
-            ));
-        };
-
-        let EvmResponsePayload::SignTransaction(response) = payload else {
-            return Err(Error::other(
-                "unexpected evm response payload for sign transaction request",
-            ));
-        };
-
-        let result = response
-            .result
-            .ok_or_else(|| Error::other("missing evm sign transaction result"))?;
-
-        match result {
-            EvmSignTransactionResult::Signature(signature) => {
-                Signature::try_from(signature.as_slice())
-                    .map_err(|_| Error::other("invalid signature returned by server"))
-            }
-            EvmSignTransactionResult::EvalError(eval_error) => Err(Error::other(
-                ArbiterEvmSignTransactionError::PolicyEval(eval_error),
-            )),
-            EvmSignTransactionResult::Error(code) => Err(Error::other(format!(
-                "server failed to sign transaction with error code {code}"
-            ))),
-        }
+        Err(EvmWalletError::new(EvmTransactionSigningUnsupportedError).into())
     }
 }

server/crates/arbiter-crypto/.gitignore

@@ -1 +0,0 @@
-/target

server/crates/arbiter-crypto/Cargo.toml

@@ -1,26 +0,0 @@
-[package]
-name = "arbiter-crypto"
-version = "0.1.0"
-edition = "2024"
-
-[dependencies]
-ml-dsa = {workspace = true, optional = true }
-rand = {workspace = true, optional = true}
-memsafe = {version = "0.4.0", optional = true}
-strum = { workspace = true, optional = true }
-hmac.workspace = true
-alloy.workspace = true
-x-wing = { version = "0.1.0-rc.0", features = ["zeroize"] }
-chrono.workspace = true
-thiserror.workspace = true
-
-[lints]
-workspace = true
-
-[features]
-default = ["authn", "safecell"]
-authn = ["dep:ml-dsa", "dep:rand", "dep:strum"]
-safecell = ["dep:memsafe"]
-
-[lib]
-doctest = false

server/crates/arbiter-crypto/src/authn/mod.rs

@@ -1,2 +0,0 @@
-pub mod v1;
-pub use v1::*;

server/crates/arbiter-crypto/src/authn/v1.rs

@@ -1,288 +0,0 @@
-use chrono::{DateTime, Utc};
-use hmac::digest::Digest;
-use ml_dsa::{
-    EncodedVerifyingKey, Error, KeyGen, MlDsa87, Seed, Signature as MlDsaSignature,
-    SigningKey as MlDsaSigningKey, VerifyingKey as MlDsaVerifyingKey, signature::Keypair as _,
-};
-use rand::RngExt;
-use strum::IntoStaticStr;
-
-/// Domain separation tag mixed into every ML-DSA signature.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, IntoStaticStr)]
-pub enum SigningContext {
-    #[strum(serialize = "arbiter_client")]
-    Client,
-    #[strum(serialize = "arbiter_operator")]
-    Operator,
-    #[strum(serialize = "arbiter_governance_vote")]
-    GovernanceVote,
-}
-
-impl SigningContext {
-    #[must_use]
-    pub fn as_bytes(self) -> &'static [u8] {
-        <&'static str>::from(self).as_bytes()
-    }
-}
-
-const NONCE_SIZE: usize = 32;
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, thiserror::Error)]
-#[error("invalid length: expected {expected} bytes, got {actual} bytes")]
-pub struct InvalidLength {
-    pub expected: usize,
-    pub actual: usize,
-}
-
-#[derive(Debug, Clone)]
-pub struct AuthChallenge {
-    pub nonce: [u8; NONCE_SIZE],
-    pub timestamp: DateTime<Utc>,
-}
-
-impl AuthChallenge {
-    pub fn generate(rng: &mut impl rand::CryptoRng) -> Self {
-        let timestamp = Utc::now();
-        let nonce = {
-            let mut array = [0; NONCE_SIZE];
-            rng.fill(&mut array);
-            array
-        };
-
-        Self { nonce, timestamp }
-    }
-
-    pub fn format(&self) -> Vec<u8> {
-        {
-            let mut buffer = Vec::from(self.nonce);
-
-            let stamp = self
-                .timestamp
-                .timestamp_nanos_opt()
-                .expect("We would be long dead by the time this triggers :)");
-            buffer.extend_from_slice(stamp.to_be_bytes().as_slice());
-
-            buffer
-        }
-    }
-
-    pub fn from_parts(nonce: &[u8], timestamp: i64) -> Result<Self, InvalidLength> {
-        let random_nonce = nonce.as_array().ok_or(InvalidLength {
-            expected: NONCE_SIZE,
-            actual: nonce.len(),
-        })?;
-        Ok(Self {
-            nonce: *random_nonce,
-            timestamp: DateTime::from_timestamp_nanos(timestamp),
-        })
-    }
-}
-
-pub type KeyParams = MlDsa87;
-
-#[derive(Clone, Debug, PartialEq)]
-pub struct PublicKey(Box<MlDsaVerifyingKey<KeyParams>>);
-
-impl crate::hashing::Hashable for PublicKey {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.to_bytes());
-    }
-}
-
-#[derive(Clone, Debug, PartialEq)]
-pub struct Signature(Box<MlDsaSignature<KeyParams>>);
-
-#[derive(Debug)]
-pub struct SigningKey(Box<MlDsaSigningKey<KeyParams>>);
-
-impl PublicKey {
-    pub fn to_bytes(&self) -> Vec<u8> {
-        self.0.encode().0.to_vec()
-    }
-
-    #[must_use]
-    pub fn verify(
-        &self,
-        challenge: &AuthChallenge,
-        context: SigningContext,
-        signature: &Signature,
-    ) -> bool {
-        let challenge = challenge.format();
-        self.0
-            .verify_with_context(&challenge, context.as_bytes(), &signature.0)
-    }
-
-    #[must_use]
-    pub fn verify_message(
-        &self,
-        message: &[u8],
-        context: SigningContext,
-        signature: &Signature,
-    ) -> bool {
-        self.0
-            .verify_with_context(message, context.as_bytes(), &signature.0)
-    }
-}
-
-impl Signature {
-    pub fn to_bytes(&self) -> Vec<u8> {
-        self.0.encode().0.to_vec()
-    }
-}
-
-impl SigningKey {
-    pub fn generate() -> Self {
-        Self(Box::new(KeyParams::key_gen(&mut rand::rng())))
-    }
-
-    pub fn from_seed(seed: [u8; 32]) -> Self {
-        Self(Box::new(KeyParams::from_seed(&Seed::from(seed))))
-    }
-
-    pub fn to_seed(&self) -> [u8; 32] {
-        self.0.to_seed().into()
-    }
-
-    pub fn public_key(&self) -> PublicKey {
-        self.0.verifying_key().into()
-    }
-
-    pub fn sign_message(
-        &self,
-        message: &[u8],
-        context: SigningContext,
-    ) -> Result<Signature, Error> {
-        self.0
-            .signing_key()
-            .sign_deterministic(message, context.as_bytes())
-            .map(Into::into)
-    }
-
-    pub fn sign_challenge(
-        &self,
-        challenge: &AuthChallenge,
-        context: SigningContext,
-    ) -> Result<Signature, Error> {
-        let challenge = challenge.format();
-
-        self.sign_message(&challenge, context)
-    }
-}
-
-impl From<MlDsaVerifyingKey<KeyParams>> for PublicKey {
-    fn from(value: MlDsaVerifyingKey<KeyParams>) -> Self {
-        Self(Box::new(value))
-    }
-}
-
-impl From<MlDsaSignature<KeyParams>> for Signature {
-    fn from(value: MlDsaSignature<KeyParams>) -> Self {
-        Self(Box::new(value))
-    }
-}
-
-impl From<MlDsaSigningKey<KeyParams>> for SigningKey {
-    fn from(value: MlDsaSigningKey<KeyParams>) -> Self {
-        Self(Box::new(value))
-    }
-}
-
-impl TryFrom<Vec<u8>> for PublicKey {
-    type Error = ();
-
-    fn try_from(value: Vec<u8>) -> Result<Self, Self::Error> {
-        Self::try_from(value.as_slice())
-    }
-}
-
-impl TryFrom<&'_ [u8]> for PublicKey {
-    type Error = ();
-
-    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
-        let encoded = EncodedVerifyingKey::<KeyParams>::try_from(value).map_err(|_| ())?;
-        Ok(Self(Box::new(MlDsaVerifyingKey::decode(&encoded))))
-    }
-}
-
-impl TryFrom<Vec<u8>> for Signature {
-    type Error = ();
-
-    fn try_from(value: Vec<u8>) -> Result<Self, Self::Error> {
-        Self::try_from(value.as_slice())
-    }
-}
-
-impl TryFrom<&'_ [u8]> for Signature {
-    type Error = ();
-
-    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
-        MlDsaSignature::try_from(value)
-            .map(|sig| Self(Box::new(sig)))
-            .map_err(|_| ())
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use ml_dsa::{KeyGen, MlDsa87, signature::Keypair as _};
-
-    use crate::authn::AuthChallenge;
-
-    use super::{PublicKey, Signature, SigningContext, SigningKey};
-
-    #[test]
-    fn public_key_round_trip_decodes() {
-        let key = MlDsa87::key_gen(&mut rand::rng());
-        let encoded = PublicKey::from(key.verifying_key()).to_bytes();
-
-        let decoded = PublicKey::try_from(encoded.as_slice()).expect("public key should decode");
-
-        assert_eq!(decoded, PublicKey::from(key.verifying_key()));
-    }
-
-    #[test]
-    fn signature_round_trip_decodes() {
-        let key = SigningKey::generate();
-        let signature = key
-            .sign_message(b"challenge", SigningContext::Client)
-            .expect("signature should be created");
-
-        let decoded =
-            Signature::try_from(signature.to_bytes().as_slice()).expect("signature should decode");
-
-        assert_eq!(decoded, signature);
-    }
-
-    #[test]
-    fn challenge_verification_uses_context_and_canonical_key_bytes() {
-        let key = SigningKey::generate();
-        let public_key = key.public_key();
-        let challenge = AuthChallenge::generate(&mut rand::rng());
-        let signature = key
-            .sign_challenge(&challenge, SigningContext::Client)
-            .expect("signature should be created");
-
-        assert!(public_key.verify(&challenge, SigningContext::Client, &signature));
-        assert!(!public_key.verify(&challenge, SigningContext::Operator, &signature));
-    }
-
-    #[test]
-    fn signing_key_round_trip_seed_preserves_public_key_and_signing() {
-        let original = SigningKey::generate();
-        let restored = SigningKey::from_seed(original.to_seed());
-
-        assert_eq!(restored.public_key(), original.public_key());
-
-        let challenge = AuthChallenge::generate(&mut rand::rng());
-
-        let signature = restored
-            .sign_challenge(&challenge, SigningContext::Client)
-            .expect("signature should be created");
-
-        assert!(
-            restored
-                .public_key()
-                .verify(&challenge, SigningContext::Client, &signature)
-        );
-    }
-}

server/crates/arbiter-crypto/src/hashing.rs

@@ -1,112 +0,0 @@
-use std::collections::HashSet;
-
-pub use hmac::digest::Digest;
-
-/// Deterministically hash a value by feeding its fields into the hasher in a consistent order.
-#[diagnostic::on_unimplemented(
-    note = "for local types consider adding `#[derive(arbiter_macros::Hashable)]` to your `{Self}` type",
-    note = "for types from other crates check whether the crate offers a `Hashable` implementation"
-)]
-pub trait Hashable {
-    fn hash<H: Digest>(&self, hasher: &mut H);
-}
-
-macro_rules! impl_numeric {
-    ($($t:ty),*) => {
-        $(
-            impl Hashable for $t {
-                fn hash<H: Digest>(&self, hasher: &mut H) {
-                    hasher.update(&self.to_be_bytes());
-                }
-            }
-        )*
-    };
-}
-
-impl_numeric!(u8, u16, u32, u64, i8, i16, i32, i64);
-
-impl Hashable for &[u8] {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self);
-    }
-}
-
-impl Hashable for String {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.as_bytes());
-    }
-}
-
-impl<T: Hashable + PartialOrd> Hashable for Vec<T> {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        let ref_sorted = {
-            let mut sorted = self.iter().collect::<Vec<_>>();
-            sorted.sort_by(|a, b| a.partial_cmp(b).unwrap());
-            sorted
-        };
-        for item in ref_sorted {
-            item.hash(hasher);
-        }
-    }
-}
-
-impl<T: Hashable + PartialOrd, S: std::hash::BuildHasher> Hashable for HashSet<T, S> {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        let ref_sorted = {
-            let mut sorted = self.iter().collect::<Vec<_>>();
-            sorted.sort_by(|a, b| a.partial_cmp(b).unwrap());
-            sorted
-        };
-        for item in ref_sorted {
-            item.hash(hasher);
-        }
-    }
-}
-
-impl<T: Hashable> Hashable for Option<T> {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        match self {
-            Some(value) => {
-                hasher.update([1]);
-                value.hash(hasher);
-            }
-            None => hasher.update([0]),
-        }
-    }
-}
-
-impl<T: Hashable> Hashable for Box<T> {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        self.as_ref().hash(hasher);
-    }
-}
-
-impl<T: Hashable> Hashable for &T {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        (*self).hash(hasher);
-    }
-}
-
-impl Hashable for alloy::primitives::Address {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.as_slice());
-    }
-}
-
-impl Hashable for alloy::primitives::U256 {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.to_be_bytes::<32>());
-    }
-}
-
-impl Hashable for chrono::Duration {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.num_seconds().to_be_bytes());
-    }
-}
-
-impl Hashable for chrono::DateTime<chrono::Utc> {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.timestamp_millis().to_be_bytes());
-    }
-}

server/crates/arbiter-crypto/src/lib.rs

@@ -1,7 +0,0 @@
-#[cfg(feature = "authn")]
-pub mod authn;
-pub mod hashing;
-#[cfg(feature = "safecell")]
-pub mod safecell;
-
-pub use x_wing;

server/crates/arbiter-macros/Cargo.toml

@@ -1,19 +0,0 @@
-[package]
-name = "arbiter-macros"
-version = "0.1.0"
-edition = "2024"
-
-[lib]
-proc-macro = true
-doctest = false
-
-[dependencies]
-proc-macro2 = "1.0"
-quote = "1.0"
-syn = { version = "2.0", features = ["derive", "fold", "full", "visit-mut"] }
-
-[dev-dependencies]
-arbiter-crypto = { path = "../arbiter-crypto" }
-
-[lints]
-workspace = true

server/crates/arbiter-macros/src/hashable.rs

@@ -1,131 +0,0 @@
-use crate::utils::{HASHABLE_TRAIT_PATH, HMAC_DIGEST_PATH};
-
-use proc_macro2::{Span, TokenStream, TokenTree};
-use quote::quote;
-use syn::{DataStruct, DeriveInput, Fields, Generics, Index, parse_quote, spanned::Spanned};
-
-pub(crate) fn derive(input: &DeriveInput) -> TokenStream {
-    match &input.data {
-        syn::Data::Struct(struct_data) => hashable_struct(input, struct_data),
-        syn::Data::Enum(_) => {
-            syn::Error::new_spanned(input, "Hashable can currently be derived only for structs")
-                .to_compile_error()
-        }
-        syn::Data::Union(_) => {
-            syn::Error::new_spanned(input, "Hashable cannot be derived for unions")
-                .to_compile_error()
-        }
-    }
-}
-
-fn hashable_struct(input: &DeriveInput, struct_data: &DataStruct) -> TokenStream {
-    let ident = &input.ident;
-    let hashable_trait = HASHABLE_TRAIT_PATH.to_path();
-    let hmac_digest = HMAC_DIGEST_PATH.to_path();
-    let generics = add_hashable_bounds(input.generics.clone(), &hashable_trait);
-    let field_accesses = collect_field_accesses(struct_data);
-    let hash_calls = build_hash_calls(&field_accesses, &hashable_trait);
-
-    let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
-
-    quote! {
-        #[automatically_derived]
-        impl #impl_generics #hashable_trait for #ident #ty_generics #where_clause {
-            fn hash<H: #hmac_digest>(&self, hasher: &mut H) {
-                #(#hash_calls)*
-            }
-        }
-    }
-}
-
-fn add_hashable_bounds(mut generics: Generics, hashable_trait: &syn::Path) -> Generics {
-    for type_param in generics.type_params_mut() {
-        type_param.bounds.push(parse_quote!(#hashable_trait));
-    }
-
-    generics
-}
-
-struct FieldAccess {
-    access: TokenStream,
-    span: Span,
-}
-
-fn collect_field_accesses(struct_data: &DataStruct) -> Vec<FieldAccess> {
-    match &struct_data.fields {
-        Fields::Named(fields) => {
-            // Keep deterministic alphabetical order for named fields.
-            // Do not remove this sort, because it keeps hash output stable regardless of source order.
-            let mut named_fields = fields
-                .named
-                .iter()
-                .map(|field| {
-                    let name = field
-                        .ident
-                        .as_ref()
-                        .expect("Fields::Named(fields) must have names")
-                        .clone();
-                    (name.to_string(), name)
-                })
-                .collect::<Vec<_>>();
-
-            named_fields.sort_by(|a, b| a.0.cmp(&b.0));
-
-            named_fields
-                .into_iter()
-                .map(|(_, name)| FieldAccess {
-                    access: quote! { #name },
-                    span: name.span(),
-                })
-                .collect()
-        }
-        Fields::Unnamed(fields) => fields
-            .unnamed
-            .iter()
-            .enumerate()
-            .map(|(i, field)| FieldAccess {
-                access: {
-                    let index = Index::from(i);
-                    quote! { #index }
-                },
-                span: field.ty.span(),
-            })
-            .collect(),
-        Fields::Unit => Vec::new(),
-    }
-}
-
-fn build_hash_calls(
-    field_accesses: &[FieldAccess],
-    hashable_trait: &syn::Path,
-) -> Vec<TokenStream> {
-    field_accesses
-        .iter()
-        .map(|field| {
-            let access = &field.access;
-            let call = quote! {
-                #hashable_trait::hash(&self.#access, hasher);
-            };
-
-            respan(call, field.span)
-        })
-        .collect()
-}
-
-/// Recursively set span on all tokens, including interpolated ones.
-fn respan(tokens: TokenStream, span: Span) -> TokenStream {
-    tokens
-        .into_iter()
-        .map(|tt| match tt {
-            TokenTree::Group(g) => {
-                let mut new = proc_macro2::Group::new(g.delimiter(), respan(g.stream(), span));
-                new.set_span(span);
-                TokenTree::Group(new)
-            }
-            mut other => {
-                other.set_span(span);
-                other
-            }
-        })
-        .collect()
-}

server/crates/arbiter-macros/src/lib.rs

@@ -1,10 +0,0 @@
-use syn::{DeriveInput, parse_macro_input};
-
-mod hashable;
-mod utils;
-
-#[proc_macro_derive(Hashable)]
-pub fn derive_hashable(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
-    let input = parse_macro_input!(input as DeriveInput);
-    hashable::derive(&input).into()
-}

server/crates/arbiter-macros/src/utils.rs

@@ -1,24 +0,0 @@
-pub(crate) struct ToPath(pub &'static str);
-
-impl ToPath {
-    pub(crate) fn to_path(&self) -> syn::Path {
-        syn::parse_str(self.0).expect("Invalid path")
-    }
-}
-
-macro_rules! ensure_path {
-    ($path:path as $name:ident) => {
-        const _: () = {
-            #[cfg(test)]
-            #[expect(
-                unused_imports,
-                reason = "Ensures the path is valid and will cause a compile error if not"
-            )]
-            use $path as _;
-        };
-        pub(crate) const $name: ToPath = ToPath(stringify!($path));
-    };
-}
-
-ensure_path!(::arbiter_crypto::hashing::Hashable as HASHABLE_TRAIT_PATH);
-ensure_path!(::arbiter_crypto::hashing::Digest as HMAC_DIGEST_PATH);

server/crates/arbiter-proto/Cargo.toml

@@ -9,27 +9,28 @@ license = "Apache-2.0"
 tonic.workspace = true
 tokio.workspace = true
 futures.workspace = true
+hex = "0.4.3"
 tonic-prost = "0.14.5"
-prost.workspace = true
+prost = "0.14.3"
 kameo.workspace = true
 url = "2.5.8"
 miette.workspace = true
 thiserror.workspace = true
 rustls-pki-types.workspace = true
-base64.workspace = true
+base64 = "0.22.1"
 prost-types.workspace = true
+tracing.workspace = true
 async-trait.workspace = true
 tokio-stream.workspace = true
 
 [build-dependencies]
 tonic-prost-build = "0.14.5"
+protoc-bin-vendored = "3"
 
 [dev-dependencies]
 rstest.workspace = true
+rand.workspace = true
 rcgen.workspace = true
 
-[lib]
-doctest = false
-
 [package.metadata.cargo-shear]
-ignored = ["tonic-prost", "prost"]
+ignored = ["tonic-prost", "prost", "kameo"]

server/crates/arbiter-proto/build.rs

@@ -1,21 +1,32 @@
+use std::path::PathBuf;
 use tonic_prost_build::configure;
 
 static PROTOBUF_DIR: &str = "../../../protobufs";
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
-    println!("cargo::rerun-if-changed={PROTOBUF_DIR}");
+    let manifest_dir = PathBuf::from(std::env::var("CARGO_MANIFEST_DIR")?);
+    let protobuf_dir = manifest_dir.join(PROTOBUF_DIR);
+    let protoc_include = protoc_bin_vendored::include_path()?;
+    let protoc_path = protoc_bin_vendored::protoc_bin_path()?;
+
+    unsafe {
+        std::env::set_var("PROTOC", &protoc_path);
+        std::env::set_var("PROTOC_INCLUDE", &protoc_include);
+    }
+
+    println!("cargo::rerun-if-changed={}", protobuf_dir.display());
 
     configure()
         .message_attribute(".", "#[derive(::kameo::Reply)]")
+        .compile_well_known_types(true)
         .compile_protos(
             &[
-                format!("{}/arbiter.proto", PROTOBUF_DIR),
-                format!("{}/operator.proto", PROTOBUF_DIR),
-                format!("{}/client.proto", PROTOBUF_DIR),
-                format!("{}/evm.proto", PROTOBUF_DIR),
+                protobuf_dir.join("arbiter.proto"),
+                protobuf_dir.join("user_agent.proto"),
+                protobuf_dir.join("client.proto"),
+                protobuf_dir.join("evm.proto"),
             ],
-            &[PROTOBUF_DIR.to_string()],
-        )
-        .unwrap();
+            &[protobuf_dir],
+        )?;
     Ok(())
 }

server/crates/arbiter-proto/src/lib.rs

@@ -1,67 +1,23 @@
 pub mod transport;
 pub mod url;
 
+use base64::{Engine, prelude::BASE64_STANDARD};
+
+pub mod google {
+    pub mod protobuf {
+        tonic::include_proto!("google.protobuf");
+    }
+}
+
 pub mod proto {
     tonic::include_proto!("arbiter");
 
-    pub mod shared {
-        tonic::include_proto!("arbiter.shared");
-
-        pub mod evm {
-            tonic::include_proto!("arbiter.shared.evm");
-        }
-    }
-
-    pub mod operator {
-        tonic::include_proto!("arbiter.operator");
-
-        pub mod auth {
-            tonic::include_proto!("arbiter.operator.auth");
-        }
-
-        pub mod evm {
-            tonic::include_proto!("arbiter.operator.evm");
-        }
-
-        pub mod governance {
-            tonic::include_proto!("arbiter.operator.governance");
-        }
-
-        pub mod sdk_client {
-            tonic::include_proto!("arbiter.operator.sdk_client");
-        }
-
-        pub mod vault {
-            tonic::include_proto!("arbiter.operator.vault");
-
-            pub mod bootstrap {
-                tonic::include_proto!("arbiter.operator.vault.bootstrap");
-            }
-
-            pub mod rekey {
-                tonic::include_proto!("arbiter.operator.vault.rekey");
-            }
-
-            pub mod unseal {
-                tonic::include_proto!("arbiter.operator.vault.unseal");
-            }
-        }
+    pub mod user_agent {
+        tonic::include_proto!("arbiter.user_agent");
     }
 
     pub mod client {
         tonic::include_proto!("arbiter.client");
-
-        pub mod auth {
-            tonic::include_proto!("arbiter.client.auth");
-        }
-
-        pub mod evm {
-            tonic::include_proto!("arbiter.client.evm");
-        }
-
-        pub mod vault {
-            tonic::include_proto!("arbiter.client.vault");
-        }
     }
 
     pub mod evm {
@@ -69,13 +25,6 @@ pub mod proto {
     }
 }
 
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub struct ClientMetadata {
-    pub name: String,
-    pub description: Option<String>,
-    pub version: Option<String>,
-}
-
 pub static BOOTSTRAP_PATH: &str = "bootstrap_token";
 
 pub fn home_path() -> Result<std::path::PathBuf, std::io::Error> {
@@ -90,3 +39,8 @@ pub fn home_path() -> Result<std::path::PathBuf, std::io::Error> {
 
     Ok(arbiter_home)
 }
+
+pub fn format_challenge(nonce: i32, pubkey: &[u8]) -> Vec<u8> {
+    let concat_form = format!("{}:{}", nonce, BASE64_STANDARD.encode(pubkey));
+    concat_form.into_bytes()
+}

server/crates/arbiter-proto/src/transport.rs

@@ -54,10 +54,11 @@
 //!   as a closed outbound channel.
 //! - [`Bi::recv`] returns `None` when the underlying transport closes.
 //! - Message translation is intentionally out of scope for this module.
-use async_trait::async_trait;
-use kameo::{error::Infallible, prelude::*};
+
 use std::marker::PhantomData;
 
+use async_trait::async_trait;
+
 /// Errors returned by transport adapters implementing [`Bi`].
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
@@ -105,36 +106,6 @@ pub trait Receiver<Inbound>: Send + Sync {
 /// any built-in correlation mechanism between inbound and outbound items.
 pub trait Bi<Inbound, Outbound>: Sender<Outbound> + Receiver<Inbound> + Send + Sync {}
 
-#[async_trait]
-impl<T, Outbound> Sender<Outbound> for &mut T
-where
-    T: Sender<Outbound> + ?Sized,
-    Outbound: Send + 'static,
-{
-    async fn send(&mut self, item: Outbound) -> Result<(), Error> {
-        (**self).send(item).await
-    }
-}
-
-#[async_trait]
-impl<T, Inbound> Receiver<Inbound> for &mut T
-where
-    T: Receiver<Inbound> + ?Sized,
-    Inbound: Send + 'static,
-{
-    async fn recv(&mut self) -> Option<Inbound> {
-        (**self).recv().await
-    }
-}
-
-impl<T, Inbound, Outbound> Bi<Inbound, Outbound> for &mut T
-where
-    T: Bi<Inbound, Outbound> + ?Sized,
-    Inbound: Send + 'static,
-    Outbound: Send + 'static,
-{
-}
-
 pub trait SplittableBi<Inbound, Outbound>: Bi<Inbound, Outbound> {
     type Sender: Sender<Outbound>;
     type Receiver: Receiver<Inbound>;
@@ -190,29 +161,3 @@ where
 }
 
 pub mod grpc;
-
-#[derive(thiserror::Error, Debug)]
-pub enum ForwardError<I> {
-    #[error("Transport error: {0}")]
-    Transport(#[from] Error),
-    #[error("Actor delivery error: {0}")]
-    Actor(SendError<I>),
-}
-
-pub async fn forward_to_actor<Transport, Inbound, Outbound, Handler>(
-    transport: &mut Transport,
-    actor: &ActorRef<Handler>,
-) -> Result<(), ForwardError<Inbound>>
-where
-    Transport: Bi<Inbound, <Outbound as Reply>::Ok>,
-    Handler: Actor + Message<Inbound, Reply = Outbound>,
-    Inbound: Send + 'static,
-    Outbound: Send + 'static + Reply<Error = Infallible>, // `Infallible` to enforce contract that `Outbound` carries handler-level error
-{
-    while let Some(request) = transport.recv().await {
-        let resp = actor.ask(request).await.map_err(ForwardError::Actor)?;
-        transport.send(resp).await?
-    }
-
-    Err(Error::ChannelClosed.into())
-}

server/crates/arbiter-proto/src/transport/grpc.rs

@@ -1,10 +1,10 @@
-use super::{Bi, Receiver, Sender};
-
 use async_trait::async_trait;
 use futures::StreamExt;
 use tokio::sync::mpsc;
 use tokio_stream::wrappers::ReceiverStream;
 
+use super::{Bi, Receiver, Sender};
+
 pub struct GrpcSender<Outbound> {
     tx: mpsc::Sender<Result<Outbound, tonic::Status>>,
 }

server/crates/arbiter-proto/src/url.rs

@@ -1,12 +1,12 @@
+use std::fmt::Display;
+
 use base64::{Engine as _, prelude::BASE64_URL_SAFE};
 use rustls_pki_types::CertificateDer;
-use std::fmt::Display;
 
 const ARBITER_URL_SCHEME: &str = "arbiter";
 const CERT_QUERY_KEY: &str = "cert";
 const BOOTSTRAP_TOKEN_QUERY_KEY: &str = "bootstrap_token";
 
-#[derive(Debug, Clone)]
 pub struct ArbiterUrl {
     pub host: String,
     pub port: u16,
@@ -104,7 +104,7 @@ mod tests {
 
     #[rstest]
 
-    fn parsing_correctness(
+    fn test_parsing_correctness(
         #[values("127.0.0.1", "localhost", "192.168.1.1", "some.domain.com")] host: &str,
 
         #[values(None, Some("token123".to_string()))] bootstrap_token: Option<String>,

server/crates/arbiter-server/Cargo.toml

@@ -9,16 +9,15 @@ license = "Apache-2.0"
 workspace = true
 
 [dependencies]
-diesel = { version = "2.3.9", features = ["chrono", "returning_clauses_for_sqlite_3_35", "serde_json", "time", "uuid"] }
-diesel-async = { version = "0.9.0", features = [
+diesel = { version = "2.3.7", features = ["chrono", "returning_clauses_for_sqlite_3_35", "serde_json", "time", "uuid"] }
+diesel-async = { version = "0.8.0", features = [
     "bb8",
     "migrations",
     "sqlite",
     "tokio",
 ] }
+ed25519-dalek.workspace = true
 arbiter-proto.path = "../arbiter-proto"
-arbiter-crypto.path = "../arbiter-crypto"
-arbiter-macros.path = "../arbiter-macros"
 tracing.workspace = true
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
 tonic.workspace = true
@@ -26,41 +25,35 @@ tonic.features = ["tls-aws-lc"]
 tokio.workspace = true
 rustls.workspace = true
 smlang.workspace = true
+miette.workspace = true
 thiserror.workspace = true
-diesel_migrations = { version = "2.3.2", features = ["sqlite"] }
+fatality = "0.1.1"
+diesel_migrations = { version = "2.3.1", features = ["sqlite"] }
 async-trait.workspace = true
+secrecy = "0.10.3"
+futures.workspace = true
 tokio-stream.workspace = true
+dashmap = "6.1.0"
 rand.workspace = true
 rcgen.workspace = true
 chrono.workspace = true
+memsafe = "0.4.0"
+zeroize = { version = "1.8.2", features = ["std", "simd"] }
 kameo.workspace = true
+x25519-dalek.workspace = true
 chacha20poly1305 = { version = "0.10.1", features = ["std"] }
 argon2 = { version = "0.5.3", features = ["zeroize"] }
 restructed = "0.2.2"
-strum.workspace = true
+strum = { version = "0.28.0", features = ["derive"] }
 pem = "3.0.6"
+k256.workspace = true
+rsa.workspace = true
 sha2.workspace = true
-hmac.workspace = true
+spki.workspace = true
 alloy.workspace = true
-prost.workspace = true
 prost-types.workspace = true
 arbiter-tokens-registry.path = "../arbiter-tokens-registry"
-anyhow = "1.0.102"
-mutants.workspace = true
-subtle = "2.6.1"
-x25519-dalek.workspace = true
-k256.workspace = true
-kameo_actors.workspace = true
-vsss-rs = "5.4.0"
-rand_core = "0.6"
 
 [dev-dependencies]
-proptest = "1.11.0"
-rstest.workspace = true
+insta = "1.46.3"
 test-log = { version = "0.2", default-features = false, features = ["trace"] }
-ml-dsa.workspace = true
-mockall = "0.15.0"
-tempfile = "3.27.0"
-
-[lib]
-doctest = false

server/crates/arbiter-server/migrations/2026-02-14-171124-0000_init/up.sql

@@ -37,67 +37,28 @@ create table if not exists tls_history (
 create table if not exists arbiter_settings (
     id INTEGER not null PRIMARY KEY CHECK (id = 1), -- singleton row, id must be 1
     root_key_id integer references root_key_history (id) on delete RESTRICT, -- if null, means wasn't bootstrapped yet
-    tls_id integer references tls_history (id) on delete RESTRICT,
-    -- Shamir threshold of the split that produced the stored shares. Null before bootstrap.
-    -- Recorded rather than recomputed: an aborted operator replacement leaves fewer share
-    -- rows than the split has shares, and a recomputed threshold would then be wrong.
-    shamir_threshold integer
+    tls_id integer references tls_history (id) on delete RESTRICT
 ) STRICT;
 
-insert into arbiter_settings (id) values (1) on conflict do nothing;
--- ensure singleton row exists
+insert into arbiter_settings (id) values (1) on conflict do nothing; -- ensure singleton row exists
 
-create table if not exists operator_identity (
+create table if not exists useragent_client (
     id integer not null primary key,
+    nonce integer not null default(1), -- used for auth challenge
     public_key blob not null,
+    key_type integer not null default(1), -- 1=Ed25519, 2=ECDSA(secp256k1)
     created_at integer not null default(unixepoch ('now')),
     updated_at integer not null default(unixepoch ('now'))
 ) STRICT;
-create unique index if not exists uniq_operator_identity_public_key on operator_identity (public_key);
-
-create table if not exists operator (
-    id integer primary key references operator_identity(id) on delete restrict, -- same id as operator_identity
-
-    share blob not null,
-    share_nonce blob not null,
-    share_salt blob not null,
-
-    created_at integer not null default(unixepoch ('now')),
-    updated_at integer not null default(unixepoch ('now'))
-
-) STRICT;
-
-create table if not exists client_metadata (
-    id integer not null primary key,
-    name text not null, -- human-readable name for the client
-    description text, -- optional description for the client
-    version text, -- client version for tracking and debugging
-    created_at integer not null default(unixepoch ('now'))
-) STRICT;
-
--- created to track history of changes
-create table if not exists client_metadata_history (
-    id integer not null primary key,
-    metadata_id integer not null references client_metadata (id) on delete cascade,
-    client_id integer not null references program_client (id) on delete cascade,
-    created_at integer not null default(unixepoch ('now'))
-) STRICT;
-
-create unique index if not exists uniq_metadata_binding_client on client_metadata_history (client_id);
 
 create table if not exists program_client (
     id integer not null primary key,
+    nonce integer not null default(1), -- used for auth challenge
     public_key blob not null,
-    metadata_id integer not null references client_metadata (id) on delete cascade,
     created_at integer not null default(unixepoch ('now')),
     updated_at integer not null default(unixepoch ('now'))
 ) STRICT;
 
-create unique index if not exists program_client_public_key_unique
-    on program_client (public_key);
-
-create unique index if not exists uniq_program_client_public_key on program_client (public_key);
-
 create table if not exists evm_wallet (
     id integer not null primary key,
     address blob not null, -- 20-byte Ethereum address
@@ -106,19 +67,8 @@ create table if not exists evm_wallet (
 ) STRICT;
 
 create unique index if not exists uniq_evm_wallet_address on evm_wallet (address);
-
 create unique index if not exists uniq_evm_wallet_aead on evm_wallet (aead_encrypted_id);
 
-create table if not exists evm_wallet_access (
-    id integer not null primary key,
-    wallet_id integer not null references evm_wallet (id) on delete cascade,
-    client_id integer not null references program_client (id) on delete cascade,
-    revoked_at integer, -- unix timestamp when revoked, null = still active
-    created_at integer not null default(unixepoch ('now'))
-) STRICT;
-
-create unique index if not exists uniq_wallet_access on evm_wallet_access (wallet_id, client_id);
-
 create table if not exists evm_ether_transfer_limit (
     id integer not null primary key,
     window_secs integer not null,           -- window duration in seconds
@@ -128,7 +78,8 @@ create table if not exists evm_ether_transfer_limit (
 -- Shared grant properties: client scope, timeframe, fee caps, and rate limit
 create table if not exists evm_basic_grant (
     id integer not null primary key,
-    wallet_access_id integer not null references evm_wallet_access (id) on delete restrict,
+    wallet_id integer not null references evm_wallet(id) on delete restrict, 
+    client_id integer not null references program_client(id) on delete restrict,
     chain_id integer not null,              -- EIP-155 chain ID
     valid_from integer,                     -- unix timestamp (seconds), null = no lower bound
     valid_until integer,                    -- unix timestamp (seconds), null = no upper bound
@@ -137,27 +88,28 @@ create table if not exists evm_basic_grant (
     rate_limit_count integer,               -- max transactions in window, null = unlimited
     rate_limit_window_secs integer,         -- window duration in seconds, null = unlimited
     revoked_at integer,                     -- unix timestamp when revoked, null = still active
-    created_at integer not null default(unixepoch ('now'))
+    created_at integer not null default(unixepoch('now'))
 ) STRICT;
 
 -- Shared transaction log for all EVM grants, used for rate limit tracking and auditing
 create table if not exists evm_transaction_log (
     id integer not null primary key,
-    wallet_access_id integer not null references evm_wallet_access (id) on delete restrict,
-    grant_id integer not null references evm_basic_grant (id) on delete restrict,
+    grant_id integer not null references evm_basic_grant(id) on delete restrict,
+    client_id integer not null references program_client(id) on delete restrict,
+    wallet_id integer not null references evm_wallet(id) on delete restrict,
     chain_id integer not null,
     eth_value blob not null,     -- always present on any EVM tx
-    signed_at integer not null default(unixepoch ('now'))
+    signed_at integer not null default(unixepoch('now'))
 ) STRICT;
 
-create index if not exists idx_evm_basic_grant_access_chain on evm_basic_grant (wallet_access_id, chain_id);
+create index if not exists idx_evm_basic_grant_wallet_chain on evm_basic_grant(client_id, wallet_id, chain_id);
 
 -- ===============================
 -- ERC20 token transfer grant
 -- ===============================
 create table if not exists evm_token_transfer_grant (
     id integer not null primary key,
-    basic_grant_id integer not null unique references evm_basic_grant (id) on delete cascade,
+    basic_grant_id integer not null unique references evm_basic_grant(id) on delete cascade,
     token_contract blob not null,            -- 20-byte ERC20 contract address
     receiver blob                            -- 20-byte recipient address or null if every recipient allowed
 ) STRICT;
@@ -165,7 +117,7 @@ create table if not exists evm_token_transfer_grant (
 -- Per-window volume limits for token transfer grants
 create table if not exists evm_token_transfer_volume_limit (
     id integer not null primary key,
-    grant_id integer not null references evm_token_transfer_grant (id) on delete cascade,
+    grant_id integer not null references evm_token_transfer_grant(id) on delete cascade,
     window_secs integer not null,           -- window duration in seconds
     max_volume blob not null                -- big-endian 32-byte U256
 ) STRICT;
@@ -173,204 +125,37 @@ create table if not exists evm_token_transfer_volume_limit (
 -- Log table for token transfer grant usage
 create table if not exists evm_token_transfer_log (
     id integer not null primary key,
-    grant_id integer not null references evm_token_transfer_grant (id) on delete restrict,
-    log_id integer not null references evm_transaction_log (id) on delete restrict,
+    grant_id integer not null references evm_token_transfer_grant(id) on delete restrict,
+    log_id integer not null references evm_transaction_log(id) on delete restrict,
     chain_id integer not null,              -- EIP-155 chain ID
     token_contract blob not null,           -- 20-byte ERC20 contract address
     recipient_address blob not null,        -- 20-byte recipient address
     value blob not null,                    -- big-endian 32-byte U256
-    created_at integer not null default(unixepoch ('now'))
+    created_at integer not null default(unixepoch('now'))
 ) STRICT;
 
-create index if not exists idx_token_transfer_log_grant on evm_token_transfer_log (grant_id);
+create index if not exists idx_token_transfer_log_grant on evm_token_transfer_log(grant_id);
+create index if not exists idx_token_transfer_log_log_id on evm_token_transfer_log(log_id);
+create index if not exists idx_token_transfer_log_chain on evm_token_transfer_log(chain_id);
 
-create index if not exists idx_token_transfer_log_log_id on evm_token_transfer_log (log_id);
-
-create index if not exists idx_token_transfer_log_chain on evm_token_transfer_log (chain_id);
 
 -- ===============================
 -- Ether transfer grant (uses base log)
 -- ===============================
 create table if not exists evm_ether_transfer_grant (
     id integer not null primary key,
-    basic_grant_id integer not null unique references evm_basic_grant (id) on delete cascade,
-    limit_id integer not null references evm_ether_transfer_limit (id) on delete restrict
+    basic_grant_id integer not null unique references evm_basic_grant(id) on delete cascade,
+    limit_id integer not null references evm_ether_transfer_limit(id) on delete restrict
 ) STRICT;
 
 -- Specific recipient addresses for an ether transfer grant
 create table if not exists evm_ether_transfer_grant_target (
     id integer not null primary key,
-    grant_id integer not null references evm_ether_transfer_grant (id) on delete cascade,
+    grant_id integer not null references evm_ether_transfer_grant(id) on delete cascade,
     address blob not null                   -- 20-byte recipient address
 ) STRICT;
 
-create unique index if not exists uniq_ether_transfer_target on evm_ether_transfer_grant_target (grant_id, address);
+create unique index if not exists uniq_ether_transfer_target on evm_ether_transfer_grant_target(grant_id, address);
 
--- ===============================
--- Integrity Envelopes
--- ===============================
-create table if not exists integrity_envelope (
-    id integer not null primary key,
-    entity_kind text not null,
-    entity_id blob not null,
-    payload_version integer not null,
-    key_version integer not null,
-    mac blob not null, -- 20-byte recipient address
-    signed_at integer not null default(unixepoch ('now')),
-    created_at integer not null default(unixepoch ('now'))
-) STRICT;
-
-create unique index if not exists uniq_integrity_envelope_entity on integrity_envelope (entity_kind, entity_id);
-
-create table if not exists proposal (
-    id           integer not null primary key,
-    kind         text    not null,
-    initiator_id integer not null references operator_identity(id) on delete restrict,
-    created_at   integer not null default(unixepoch('now')),
-    expires_at   integer not null,
-    status       text    not null default 'pending'
-        check (status in ('pending', 'approved', 'rejected'))
-) STRICT;
-
--- Parameters of an approved-or-pending proposal
-create table if not exists proposal_approve_sdk_client (
-    proposal_id integer not null primary key references proposal(id) on delete cascade,
-    client_id   integer not null references program_client(id) on delete restrict
-) STRICT;
-
-create table if not exists proposal_grant_wallet_access (
-    proposal_id integer not null primary key references proposal(id) on delete cascade,
-    wallet_id   integer not null references evm_wallet(id) on delete restrict,
-    client_id   integer not null references program_client(id) on delete restrict
-) STRICT;
-
-create table if not exists proposal_replace_operator (
-    proposal_id     integer not null primary key references proposal(id) on delete cascade,
-    old_operator_id integer not null references operator_identity(id) on delete restrict,
-    new_pubkey      blob    not null
-) STRICT;
-
--- The transaction an operator votes to sign.
-create table if not exists proposal_one_off_transaction (
-    proposal_id              integer not null primary key references proposal(id) on delete cascade,
-    client_id                integer not null references program_client(id) on delete restrict,
-    wallet_address           blob    not null check (length(wallet_address) = 20),
-    chain_id                 integer not null,
-    nonce                    integer not null,
-    gas_limit                integer not null,
-    max_fee_per_gas          blob    not null check (length(max_fee_per_gas) = 16),
-    max_priority_fee_per_gas blob    not null check (length(max_priority_fee_per_gas) = 16),
-    to_address               blob    not null check (length(to_address) = 20),
-    value                    blob    not null check (length(value) = 32),
-    input                    blob    not null
-) STRICT;
-
--- The grant an operator votes to creat
-create table if not exists proposal_persistent_grant (
-    proposal_id              integer not null primary key references proposal (id) on delete cascade,
-    wallet_access_id         integer not null references evm_wallet_access (id) on delete restrict,
-    chain_id                 integer not null, -- EIP-155 chain ID
-    valid_from               integer, -- unix timestamp (seconds), null = no lower bound
-    valid_until              integer, -- unix timestamp (seconds), null = no upper bound
-    max_gas_fee_per_gas      blob check (max_gas_fee_per_gas is null or length(max_gas_fee_per_gas) = 32),
-    max_priority_fee_per_gas blob check (max_priority_fee_per_gas is null or length(max_priority_fee_per_gas) = 32),
-    rate_limit_count         integer, -- max transactions in window, null = unlimited
-    rate_limit_window_secs   integer, -- window duration in seconds, null = unlimited
-    check ((rate_limit_count is null) = (rate_limit_window_secs is null))
-) STRICT;
-
--- `specific = ether_transfer`
-create table if not exists proposal_persistent_grant_ether (
-    proposal_id integer not null primary key references proposal_persistent_grant (proposal_id) on delete cascade,
-    window_secs integer not null,
-    max_volume  blob    not null check (length(max_volume) = 32)
-) STRICT;
-
-create table if not exists proposal_persistent_grant_ether_target (
-    id          integer not null primary key,
-    proposal_id integer not null references proposal_persistent_grant_ether (proposal_id) on delete cascade,
-    address     blob    not null check (length(address) = 20)
-) STRICT;
-
-create unique index if not exists uniq_proposal_ether_target on proposal_persistent_grant_ether_target (proposal_id, address);
-
--- `specific = token_transfer`
-create table if not exists proposal_persistent_grant_token (
-    proposal_id    integer not null primary key references proposal_persistent_grant (proposal_id) on delete cascade,
-    token_contract blob    not null check (length(token_contract) = 20),
-    receiver       blob check (receiver is null or length(receiver) = 20)
-) STRICT;
-
-create table if not exists proposal_persistent_grant_token_limit (
-    id          integer not null primary key,
-    proposal_id integer not null references proposal_persistent_grant_token (proposal_id) on delete cascade,
-    window_secs integer not null,
-    max_volume  blob    not null check (length(max_volume) = 32)
-) STRICT;
-
-create table if not exists proposal_vote (
-    id          integer not null primary key,
-    proposal_id integer not null references proposal(id) on delete cascade,
-    operator_id integer not null references operator_identity(id) on delete restrict,
-    approve     integer not null check (approve in (0, 1)),
-    signature   blob    not null,
-    voted_at    integer not null default(unixepoch('now')),
-    unique (proposal_id, operator_id)
-) STRICT;
-
-
--- The signature the vault produced for an approved transaction, by component.
---
--- secp256k1 signatures have three common encodings (Electrum v=27/28, raw parity,
--- ERC-2098 compact); a single blob would not say which one it holds. `y_parity` is
--- the raw bit -- add 27 to rebuild the Electrum form `Signature::as_bytes` emits.
-create table if not exists proposal_one_off_transaction_result (
-    proposal_id integer not null primary key
-        references proposal_one_off_transaction (proposal_id) on delete cascade,
-    r           blob    not null check (length(r) = 32),
-    s           blob    not null check (length(s) = 32),
-    y_parity    integer not null check (y_parity in (0, 1)),
-    created_at  integer not null default(unixepoch('now'))
-) STRICT;
-
--- ===============================
--- Recovery Operators (§3.4/§3.5/§3.6)
--- ===============================
-
--- Encrypted Shamir shares for recovery operators (mirrors the `operator` table).
-create table if not exists recovery_operator (
-    id          integer not null primary key references recovery_operator_identity(id) on delete restrict,
-    share       blob    not null,
-    share_nonce blob    not null,
-    share_salt  blob    not null,
-    created_at  integer not null default(unixepoch('now')),
-    updated_at  integer not null default(unixepoch('now'))
-) STRICT;
-
-create table if not exists recovery_operator_identity (
-    id         integer not null primary key,
-    public_key blob    not null unique,
-    created_at integer not null default(unixepoch('now')),
-    updated_at integer not null default(unixepoch('now'))
-) STRICT;
-
--- One active wakeup request at a time. A request is pending when cancelled_at IS NULL
--- and requested_at + 14 days > now. It becomes active (recovery live) after 14 days.
-create table if not exists recovery_wakeup_request (
-    id           integer not null primary key,
-    requested_by integer not null references operator_identity(id) on delete restrict,
-    requested_at integer not null default(unixepoch('now')),
-    cancelled_by integer references operator_identity(id) on delete restrict,
-    cancelled_at integer
-) STRICT;
-
--- Votes cast by recovery operators; only allowed on replace_operator proposals.
-create table if not exists recovery_proposal_vote (
-    id                   integer not null primary key,
-    proposal_id          integer not null references proposal(id) on delete cascade,
-    recovery_operator_id integer not null references recovery_operator_identity(id) on delete restrict,
-    approve              integer not null check (approve in (0, 1)),
-    signature            blob    not null,
-    voted_at             integer not null default(unixepoch('now')),
-    unique (proposal_id, recovery_operator_id)
-) STRICT;
+CREATE UNIQUE INDEX program_client_public_key_unique
+    ON program_client (public_key);

server/crates/arbiter-server/src/actors/bootstrap.rs

@@ -1,56 +1,43 @@
-use crate::db::{self, DatabasePool, schema};
 use arbiter_proto::{BOOTSTRAP_PATH, home_path};
-
 use diesel::QueryDsl;
 use diesel_async::RunQueryDsl;
 use kameo::{Actor, messages};
-use rand::{
-    distr::{Alphanumeric, SampleString as _},
-    make_rng,
-    rngs::StdRng,
-};
-use std::path::Path;
-use subtle::ConstantTimeEq as _;
+use miette::Diagnostic;
+use rand::{RngExt, distr::Alphanumeric, make_rng, rngs::StdRng};
 use thiserror::Error;
 
+use crate::db::{self, DatabasePool, schema};
 const TOKEN_LENGTH: usize = 64;
 
-pub async fn generate_token(home: &Path) -> Result<String, std::io::Error> {
-    let mut rng: StdRng = make_rng();
+pub async fn generate_token() -> Result<String, std::io::Error> {
+    let rng: StdRng = make_rng();
 
-    // `Alphanumeric` samples raw `u8` ASCII codes, not `char`s -- `SampleString::sample_string`
-    // is `rand`'s own documented way to turn that into an actual TOKEN_LENGTH-character string
-    // (see the "Passwords" example on `Alphanumeric`'s docs). A prior version of this function
-    // called `.to_string()` on the sampled `u8` directly, which stringifies the numeric byte
-    // value (e.g. `65` instead of `'A'`) rather than the character it represents, silently
-    // producing a variable-length, all-decimal-digit string instead of a real token.
-    let token = Alphanumeric.sample_string(&mut rng, TOKEN_LENGTH);
+    let token: String = rng.sample_iter(Alphanumeric).take(TOKEN_LENGTH).fold(
+        Default::default(),
+        |mut accum, char| {
+            accum += char.to_string().as_str();
+            accum
+        },
+    );
 
-    tokio::fs::write(home.join(BOOTSTRAP_PATH), token.as_str()).await?;
+    tokio::fs::write(home_path()?.join(BOOTSTRAP_PATH), token.as_str()).await?;
 
     Ok(token)
 }
 
-/// A token file is only trustworthy if it looks like something `generate_token` could have
-/// produced. Anything else -- empty (a crash between the file's truncate and write), foreign
-/// content, or a trailing newline added by an editor -- must not be adopted as a live
-/// credential: an empty file would make every empty-string token verify, and mismatched
-/// content would silently lock out every operator holding the real, already-printed token.
-#[must_use]
-fn is_valid_token(candidate: &str) -> bool {
-    candidate.len() == TOKEN_LENGTH && candidate.chars().all(|c| c.is_ascii_alphanumeric())
-}
-
-#[derive(Error, Debug)]
+#[derive(Error, Debug, Diagnostic)]
 pub enum Error {
     #[error("Database error: {0}")]
+    #[diagnostic(code(arbiter_server::bootstrap::database))]
     Database(#[from] db::PoolError),
 
-    #[error("I/O error: {0}")]
-    Io(#[from] std::io::Error),
-
     #[error("Database query error: {0}")]
+    #[diagnostic(code(arbiter_server::bootstrap::database_query))]
     Query(#[from] diesel::result::Error),
+
+    #[error("I/O error: {0}")]
+    #[diagnostic(code(arbiter_server::bootstrap::io))]
+    Io(#[from] std::io::Error),
 }
 
 #[derive(Actor)]
@@ -59,107 +46,45 @@ pub struct Bootstrapper {
 }
 
 impl Bootstrapper {
-    /// Production constructor: resolves the real `~/.arbiter` directory and delegates.
     pub async fn new(db: &DatabasePool) -> Result<Self, Error> {
-        let home = home_path()?;
-        Self::new_in(db, &home).await
-    }
-
-    /// Carries all of `new`'s logic, parameterized on the directory the token file lives in.
-    /// `new` resolves the real home directory and calls this; tests call it directly with a
-    /// throwaway temp directory so they never touch the real `~/.arbiter/bootstrap_token`.
-    pub async fn new_in(db: &DatabasePool, home: &Path) -> Result<Self, Error> {
         let mut conn = db.get().await?;
 
-        let bootstrapped: bool = schema::arbiter_settings::table
-            .select(schema::arbiter_settings::root_key_id)
-            .first::<Option<i32>>(&mut conn)
-            .await?
-            .is_some();
-
-        if bootstrapped {
-            return Ok(Self { token: None });
-        }
-
-        let any_operator_registered: bool = schema::operator_identity::table
+        let row_count: i64 = schema::useragent_client::table
             .count()
-            .get_result::<i64>(&mut conn)
-            .await?
-            > 0;
+            .get_result(&mut conn)
+            .await?;
 
-        if !any_operator_registered {
-            // Nobody has used the current token yet, so there is nothing to preserve across a
-            // restart: generate a fresh one, exactly as on a first run. Reusing an old file
-            // here would let a token survive a database reset, silently reviving trust in
-            // whoever still held it.
-            return Ok(Self {
-                token: Some(generate_token(home).await?),
-            });
-        }
+        drop(conn);
 
-        // At least one operator has already registered with the current token: every other
-        // declared operator still needs that same token, including across a restart, so an
-        // existing file is reused rather than replaced -- but only if it still looks like a
-        // real token. A truncated, foreign, or corrupted file must not become a live
-        // credential (see `is_valid_token`).
-        let path = home.join(BOOTSTRAP_PATH);
-        let token = match tokio::fs::read_to_string(&path).await {
-            Ok(existing) if is_valid_token(&existing) => existing,
-            Ok(_) => {
-                // Replacing the file invalidates whatever token the already-registered
-                // operators were handed, so it must not happen quietly. The content itself is
-                // a credential and stays out of the log; the path is enough to act on.
-                tracing::warn!(
-                    ?path,
-                    "Bootstrap token file is not a well-formed token; replacing it"
-                );
-                generate_token(home).await?
-            }
-            Err(err) if err.kind() == std::io::ErrorKind::NotFound => generate_token(home).await?,
-            Err(err) => return Err(Error::Io(err)),
+        let token = if row_count == 0 {
+            let token = generate_token().await?;
+            Some(token)
+        } else {
+            None
         };
 
-        Ok(Self { token: Some(token) })
-    }
-
-    /// Drops the token from memory. Called once the vault is bootstrapped: from then on,
-    /// operators are added through governance rather than through the token.
-    pub(crate) fn forget_token(&mut self) {
-        self.token = None;
-    }
-
-    #[must_use]
-    fn is_correct_token(&self, token: &str) -> bool {
-        self.token.as_ref().is_some_and(|expected| {
-            let expected_bytes = expected.as_bytes();
-            let token_bytes = token.as_bytes();
-
-            let choice = expected_bytes.ct_eq(token_bytes);
-            bool::from(choice)
-        })
+        Ok(Self { token })
     }
 }
 
 #[messages]
 impl Bootstrapper {
-    /// Checks the token without retiring it: every operator in a declared committee
-    /// authenticates with the same token during bootstrap.
     #[message]
-    #[must_use]
-    pub fn verify_token(&self, token: String) -> bool {
-        self.is_correct_token(&token)
+    pub fn is_correct_token(&self, token: String) -> bool {
+        match &self.token {
+            Some(expected) => *expected == token,
+            None => false,
+        }
     }
-}
 
-impl kameo::prelude::Message<crate::actors::vault::events::Bootstrapped> for Bootstrapper {
-    type Reply = ();
-
-    async fn handle(
-        &mut self,
-        _msg: crate::actors::vault::events::Bootstrapped,
-        _ctx: &mut kameo::prelude::Context<Self, Self::Reply>,
-    ) -> Self::Reply {
-        self.forget_token();
+    #[message]
+    pub fn consume_token(&mut self, token: String) -> bool {
+        if self.is_correct_token(token) {
+            self.token = None;
+            true
+        } else {
+            false
+        }
     }
 }
 
@@ -170,150 +95,3 @@ impl Bootstrapper {
         self.token.clone()
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use diesel::{ExpressionMethods as _, insert_into, update};
-
-    /// A multi-operator committee registers every member with the same token, so verifying it
-    /// must not consume it. Only a completed bootstrap retires the token.
-    #[tokio::test]
-    async fn token_verifies_repeatedly_until_bootstrap_completes() {
-        let mut bootstrapper = Bootstrapper {
-            token: Some("test-token".to_owned()),
-        };
-
-        assert!(bootstrapper.verify_token("test-token".to_owned()));
-        assert!(bootstrapper.verify_token("test-token".to_owned()));
-        assert!(!bootstrapper.verify_token("wrong-token".to_owned()));
-
-        bootstrapper.forget_token();
-
-        assert!(!bootstrapper.verify_token("test-token".to_owned()));
-        assert!(bootstrapper.get_token().is_none());
-    }
-
-    /// Once the vault is bootstrapped, `Bootstrapper::new_in` must return with no token -- and
-    /// it must do so from `arbiter_settings.root_key_id` alone, taking the early return before
-    /// `home` is ever consulted. Uses `new_in` with a throwaway temp directory (never the
-    /// production `new`, which unconditionally resolves the real home directory before this
-    /// method even runs) so this test cannot touch the real filesystem regardless of outcome.
-    #[tokio::test]
-    async fn new_returns_no_token_once_the_vault_is_bootstrapped() {
-        let db = db::create_test_pool().await;
-        let mut conn = db.get().await.unwrap();
-
-        let root_key_history_id: i32 = insert_into(schema::root_key_history::table)
-            .values(&db::models::NewRootKeyHistory {
-                ciphertext: vec![0u8; 32],
-                tag: vec![0u8; 16],
-                root_key_encryption_nonce: vec![0u8; 24],
-                data_encryption_nonce: vec![0u8; 24],
-                schema_version: 1,
-                salt: vec![0u8; 16],
-            })
-            .returning(schema::root_key_history::id)
-            .get_result(&mut conn)
-            .await
-            .unwrap();
-
-        update(schema::arbiter_settings::table)
-            .set(schema::arbiter_settings::root_key_id.eq(root_key_history_id))
-            .execute(&mut conn)
-            .await
-            .unwrap();
-        drop(conn);
-
-        let home = tempfile::tempdir().unwrap();
-        let bootstrapper = Bootstrapper::new_in(&db, home.path()).await.unwrap();
-
-        assert!(bootstrapper.get_token().is_none());
-    }
-
-    /// The file-reuse path (an operator has already registered, so bootstrap is unfinished)
-    /// must not adopt a corrupted token file as a live credential: it must reject it and
-    /// generate a fresh one instead. This is the Critical from the review, now reachable
-    /// safely because `new_in` takes a throwaway temp directory instead of the real home.
-    #[tokio::test]
-    async fn new_in_rejects_and_replaces_a_corrupted_token_file() {
-        let db = db::create_test_pool().await;
-        let mut conn = db.get().await.unwrap();
-
-        // At least one operator must have registered, or `new_in` would regenerate
-        // unconditionally regardless of the file (Important 2) and never exercise validation.
-        insert_into(schema::operator_identity::table)
-            .values(schema::operator_identity::public_key.eq(vec![0u8; 32]))
-            .execute(&mut conn)
-            .await
-            .unwrap();
-        drop(conn);
-
-        let home = tempfile::tempdir().unwrap();
-        tokio::fs::write(home.path().join(BOOTSTRAP_PATH), "")
-            .await
-            .unwrap();
-
-        let bootstrapper = Bootstrapper::new_in(&db, home.path()).await.unwrap();
-
-        let token = bootstrapper
-            .get_token()
-            .expect("a fresh token must be generated");
-        assert!(is_valid_token(&token));
-
-        // The replacement must also have landed on disk, not just in memory, so a restart
-        // reads back the same (now valid) token rather than the corrupted one again.
-        let on_disk = tokio::fs::read_to_string(home.path().join(BOOTSTRAP_PATH))
-            .await
-            .unwrap();
-        assert_eq!(on_disk, token);
-    }
-
-    /// The second defect the task exists to fix: a restart between the first registration and
-    /// the completed bootstrap must not invalidate the token the other declared operators were
-    /// already given. With an operator registered and a well-formed file on disk, `new_in` has
-    /// to hand back exactly what it read instead of generating a replacement.
-    #[tokio::test]
-    async fn new_in_reuses_a_valid_token_file_across_a_restart() {
-        let db = db::create_test_pool().await;
-        let mut conn = db.get().await.unwrap();
-
-        // Without a registered operator, `new_in` regenerates unconditionally (Important 2 of
-        // the round-2 review) and never reaches the reuse path this test is about.
-        insert_into(schema::operator_identity::table)
-            .values(schema::operator_identity::public_key.eq(vec![0u8; 32]))
-            .execute(&mut conn)
-            .await
-            .unwrap();
-        drop(conn);
-
-        let home = tempfile::tempdir().unwrap();
-        // Stands in for the token a previous run wrote and printed to the console.
-        let handed_out = "Zq7Z2rXaB90kLmNpQwErTyUiOpAsDfGhJkLzXcVbNmQwErTyUiOpAsDfGhJkLzXc";
-        assert!(is_valid_token(handed_out));
-        tokio::fs::write(home.path().join(BOOTSTRAP_PATH), handed_out)
-            .await
-            .unwrap();
-
-        let bootstrapper = Bootstrapper::new_in(&db, home.path()).await.unwrap();
-
-        assert_eq!(bootstrapper.get_token().as_deref(), Some(handed_out));
-    }
-
-    /// An empty file must not be adopted as a live credential: `is_correct_token`'s
-    /// `is_some_and` would enter its closure for `Some(String::new())`, and comparing two empty
-    /// byte slices is true, so an unauthenticated `Some("")` from the wire would otherwise
-    /// verify. Also pins the other corrupted-content shapes `is_valid_token` must reject.
-    #[test]
-    fn is_valid_token_rejects_anything_that_is_not_a_real_token() {
-        assert!(!is_valid_token(""));
-        assert!(!is_valid_token("too-short"));
-        assert!(!is_valid_token(&"a".repeat(TOKEN_LENGTH - 1)));
-        assert!(!is_valid_token(&"a".repeat(TOKEN_LENGTH + 1)));
-        // A trailing newline (e.g. from an editor) must not be silently accepted either.
-        assert!(!is_valid_token(&format!("{}\n", "a".repeat(TOKEN_LENGTH))));
-        assert!(!is_valid_token(&"!".repeat(TOKEN_LENGTH)));
-
-        assert!(is_valid_token(&"a".repeat(TOKEN_LENGTH)));
-    }
-}

server/crates/arbiter-server/src/actors/client/auth.rs

@@ -0,0 +1,249 @@
+use arbiter_proto::{
+    format_challenge,
+    transport::{Bi, expect_message},
+};
+use diesel::{
+    ExpressionMethods as _, OptionalExtension as _, QueryDsl as _, dsl::insert_into, update,
+};
+use diesel_async::RunQueryDsl as _;
+use ed25519_dalek::{Signature, VerifyingKey};
+use kameo::error::SendError;
+use tracing::error;
+
+use crate::{
+    actors::{
+        client::ClientConnection,
+        router::{self, RequestClientApproval},
+    },
+    db::{self, schema::program_client},
+};
+
+#[derive(thiserror::Error, Debug, Clone, PartialEq, Eq)]
+pub enum Error {
+    #[error("Database pool unavailable")]
+    DatabasePoolUnavailable,
+    #[error("Database operation failed")]
+    DatabaseOperationFailed,
+    #[error("Invalid challenge solution")]
+    InvalidChallengeSolution,
+    #[error("Client approval request failed")]
+    ApproveError(#[from] ApproveError),
+    #[error("Transport error")]
+    Transport,
+}
+
+#[derive(thiserror::Error, Debug, Clone, PartialEq, Eq)]
+pub enum ApproveError {
+    #[error("Internal error")]
+    Internal,
+    #[error("Client connection denied by user agents")]
+    Denied,
+    #[error("Upstream error: {0}")]
+    Upstream(router::ApprovalError),
+}
+
+#[derive(Debug, Clone)]
+pub enum Inbound {
+    AuthChallengeRequest { pubkey: VerifyingKey },
+    AuthChallengeSolution { signature: Signature },
+}
+
+#[derive(Debug, Clone)]
+pub enum Outbound {
+    AuthChallenge { pubkey: VerifyingKey, nonce: i32 },
+    AuthSuccess,
+}
+
+/// Atomically reads and increments the nonce for a known client.
+/// Returns `None` if the pubkey is not registered.
+async fn get_nonce(db: &db::DatabasePool, pubkey: &VerifyingKey) -> Result<Option<i32>, Error> {
+    let pubkey_bytes = pubkey.as_bytes().to_vec();
+
+    let mut conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::DatabasePoolUnavailable
+    })?;
+
+    conn.exclusive_transaction(|conn| {
+        let pubkey_bytes = pubkey_bytes.clone();
+        Box::pin(async move {
+            let Some((client_id, current_nonce)) = program_client::table
+                .filter(program_client::public_key.eq(&pubkey_bytes))
+                .select((program_client::id, program_client::nonce))
+                .first::<(i32, i32)>(conn)
+                .await
+                .optional()?
+            else {
+                return Result::<_, diesel::result::Error>::Ok(None);
+            };
+
+            update(program_client::table)
+                .filter(program_client::public_key.eq(&pubkey_bytes))
+                .set(program_client::nonce.eq(current_nonce + 1))
+                .execute(conn)
+                .await?;
+
+            let _ = client_id;
+            Ok(Some(current_nonce))
+        })
+    })
+    .await
+    .map_err(|e| {
+        error!(error = ?e, "Database error");
+        Error::DatabaseOperationFailed
+    })
+}
+
+async fn approve_new_client(
+    actors: &crate::actors::GlobalActors,
+    pubkey: VerifyingKey,
+) -> Result<(), Error> {
+    let result = actors
+        .router
+        .ask(RequestClientApproval {
+            client_pubkey: pubkey,
+        })
+        .await;
+
+    match result {
+        Ok(true) => Ok(()),
+        Ok(false) => Err(Error::ApproveError(ApproveError::Denied)),
+        Err(SendError::HandlerError(e)) => {
+            error!(error = ?e, "Approval upstream error");
+            Err(Error::ApproveError(ApproveError::Upstream(e)))
+        }
+        Err(e) => {
+            error!(error = ?e, "Approval request to router failed");
+            Err(Error::ApproveError(ApproveError::Internal))
+        }
+    }
+}
+
+enum InsertClientResult {
+    Inserted,
+    AlreadyExists,
+}
+
+async fn insert_client(
+    db: &db::DatabasePool,
+    pubkey: &VerifyingKey,
+) -> Result<InsertClientResult, Error> {
+    let now = std::time::SystemTime::now()
+        .duration_since(std::time::UNIX_EPOCH)
+        .unwrap_or_default()
+        .as_secs() as i32;
+
+    let mut conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::DatabasePoolUnavailable
+    })?;
+
+    match insert_into(program_client::table)
+        .values((
+            program_client::public_key.eq(pubkey.as_bytes().to_vec()),
+            program_client::nonce.eq(1), // pre-incremented; challenge uses 0
+            program_client::created_at.eq(now),
+            program_client::updated_at.eq(now),
+        ))
+        .execute(&mut conn)
+        .await
+    {
+        Ok(_) => {}
+        Err(diesel::result::Error::DatabaseError(
+            diesel::result::DatabaseErrorKind::UniqueViolation,
+            _,
+        )) => return Ok(InsertClientResult::AlreadyExists),
+        Err(e) => {
+            error!(error = ?e, "Failed to insert new client");
+            return Err(Error::DatabaseOperationFailed);
+        }
+    }
+
+    let client_id = program_client::table
+        .filter(program_client::public_key.eq(pubkey.as_bytes().to_vec()))
+        .order(program_client::id.desc())
+        .select(program_client::id)
+        .first::<i32>(&mut conn)
+        .await
+        .map_err(|e| {
+            error!(error = ?e, "Failed to load inserted client id");
+            Error::DatabaseOperationFailed
+        })?;
+
+    let _ = client_id;
+    Ok(InsertClientResult::Inserted)
+}
+
+async fn challenge_client<T>(
+    transport: &mut T,
+    pubkey: VerifyingKey,
+    nonce: i32,
+) -> Result<(), Error>
+where
+    T: Bi<Inbound, Result<Outbound, Error>> + ?Sized,
+{
+    transport
+        .send(Ok(Outbound::AuthChallenge { pubkey, nonce }))
+        .await
+        .map_err(|e| {
+            error!(error = ?e, "Failed to send auth challenge");
+            Error::Transport
+        })?;
+
+    let signature = expect_message(transport, |req: Inbound| match req {
+        Inbound::AuthChallengeSolution { signature } => Some(signature),
+        _ => None,
+    })
+    .await
+    .map_err(|e| {
+        error!(error = ?e, "Failed to receive challenge solution");
+        Error::Transport
+    })?;
+
+    let formatted = format_challenge(nonce, pubkey.as_bytes());
+
+    pubkey.verify_strict(&formatted, &signature).map_err(|_| {
+        error!("Challenge solution verification failed");
+        Error::InvalidChallengeSolution
+    })?;
+
+    Ok(())
+}
+
+pub async fn authenticate<T>(
+    props: &mut ClientConnection,
+    transport: &mut T,
+) -> Result<VerifyingKey, Error>
+where
+    T: Bi<Inbound, Result<Outbound, Error>> + Send + ?Sized,
+{
+    let Some(Inbound::AuthChallengeRequest { pubkey }) = transport.recv().await
+    else {
+        return Err(Error::Transport);
+    };
+
+    let nonce = match get_nonce(&props.db, &pubkey).await? {
+        Some(nonce) => nonce,
+        None => {
+            approve_new_client(&props.actors, pubkey).await?;
+            match insert_client(&props.db, &pubkey).await? {
+                InsertClientResult::Inserted => 0,
+                InsertClientResult::AlreadyExists => match get_nonce(&props.db, &pubkey).await? {
+                    Some(nonce) => nonce,
+                    None => return Err(Error::DatabaseOperationFailed),
+                },
+            }
+        }
+    };
+
+    challenge_client(transport, pubkey, nonce).await?;
+    transport
+        .send(Ok(Outbound::AuthSuccess))
+        .await
+        .map_err(|e| {
+            error!(error = ?e, "Failed to send auth success");
+            Error::Transport
+        })?;
+
+    Ok(pubkey)
+}

server/crates/arbiter-server/src/actors/client/mod.rs

@@ -0,0 +1,38 @@
+use arbiter_proto::transport::Bi;
+use kameo::actor::Spawn;
+use tracing::{error, info};
+
+use crate::{
+    actors::{GlobalActors, client::session::ClientSession},
+    db,
+};
+
+pub struct ClientConnection {
+    pub(crate) db: db::DatabasePool,
+    pub(crate) actors: GlobalActors,
+}
+
+impl ClientConnection {
+    pub fn new(db: db::DatabasePool, actors: GlobalActors) -> Self {
+        Self { db, actors }
+    }
+}
+
+pub mod auth;
+pub mod session;
+
+pub async fn connect_client<T>(mut props: ClientConnection, transport: &mut T)
+where
+    T: Bi<auth::Inbound, Result<auth::Outbound, auth::Error>> + Send + ?Sized,
+{
+    match auth::authenticate(&mut props, transport).await {
+        Ok(_pubkey) => {
+            ClientSession::spawn(ClientSession::new(props));
+            info!("Client authenticated, session started");
+        }
+        Err(err) => {
+            let _ = transport.send(Err(err.clone())).await;
+            error!(?err, "Authentication failed, closing connection");
+        }
+    }
+}

server/crates/arbiter-server/src/actors/client/session.rs

@@ -0,0 +1,71 @@
+use kameo::{Actor, messages};
+use tracing::error;
+
+use crate::{
+    actors::{
+        GlobalActors, client::ClientConnection, keyholder::KeyHolderState, router::RegisterClient,
+    },
+    db,
+};
+
+pub struct ClientSession {
+    props: ClientConnection,
+}
+
+impl ClientSession {
+    pub(crate) fn new(props: ClientConnection) -> Self {
+        Self { props }
+    }
+}
+
+#[messages]
+impl ClientSession {
+    #[message]
+    pub(crate) async fn handle_query_vault_state(&mut self) -> Result<KeyHolderState, Error> {
+        use crate::actors::keyholder::GetState;
+
+        let vault_state = match self.props.actors.key_holder.ask(GetState {}).await {
+            Ok(state) => state,
+            Err(err) => {
+                error!(?err, actor = "client", "keyholder.query.failed");
+                return Err(Error::Internal);
+            }
+        };
+
+        Ok(vault_state)
+    }
+}
+
+impl Actor for ClientSession {
+    type Args = Self;
+
+    type Error = Error;
+
+    async fn on_start(
+        args: Self::Args,
+        this: kameo::prelude::ActorRef<Self>,
+    ) -> Result<Self, Self::Error> {
+        args.props
+            .actors
+            .router
+            .ask(RegisterClient { actor: this })
+            .await
+            .map_err(|_| Error::ConnectionRegistrationFailed)?;
+        Ok(args)
+    }
+}
+
+impl ClientSession {
+    pub fn new_test(db: db::DatabasePool, actors: GlobalActors) -> Self {
+        let props = ClientConnection::new(db, actors);
+        Self { props }
+    }
+}
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error("Connection registration failed")]
+    ConnectionRegistrationFailed,
+    #[error("Internal error")]
+    Internal,
+}

server/crates/arbiter-server/src/actors/evm/mod.rs

@@ -1,139 +1,100 @@
-use crate::{
-    actors::{
-        proposal_manager::events::ProposalApproved,
-        vault::{CreateNew, Decrypt, Vault},
-    },
-    crypto::integrity,
-    db::{
-        DatabaseError, DatabasePool,
-        models::{self, EvmWalletId, ProposalId},
-        proposal::{ProposalKind, grant_wallet_access, one_off_transaction, persistent_grant},
-        schema,
-    },
-    evm::{
-        self, ListError, RunKind,
-        policies::{
-            CombinedSettings, Grant, SharedGrantSettings, SpecificGrant, SpecificMeaning,
-            ether_transfer::EtherTransfer, token_transfers::TokenTransfer,
-        },
-    },
-};
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
-use alloy::{
-    consensus::TxEip1559, network::TxSignerSync as _, primitives::Address, signers::Signature,
-};
+use alloy::{consensus::TxEip1559, primitives::Address, signers::Signature};
 use diesel::{
     ExpressionMethods, OptionalExtension as _, QueryDsl, SelectableHelper as _, dsl::insert_into,
 };
 use diesel_async::RunQueryDsl;
-use kameo::{Actor, actor::ActorRef, messages, prelude::Message};
+use kameo::{Actor, actor::ActorRef, messages};
 use rand::{SeedableRng, rng, rngs::StdRng};
-use tracing::error;
+
+use crate::{
+    actors::keyholder::{CreateNew, Decrypt, KeyHolder},
+    db::{
+        self, DatabasePool,
+        models::{self, SqliteTimestamp},
+        schema,
+    },
+    evm::{
+        self, ListGrantsError, RunKind,
+        policies::{
+            FullGrant, Grant, SharedGrantSettings, SpecificGrant, SpecificMeaning,
+            ether_transfer::EtherTransfer, token_transfers::TokenTransfer,
+        },
+    },
+    safe_cell::{SafeCell, SafeCellHandle as _},
+};
 
 pub use crate::evm::safe_signer;
 
-#[derive(Debug, thiserror::Error)]
+#[derive(Debug, thiserror::Error, miette::Diagnostic)]
 pub enum SignTransactionError {
     #[error("Wallet not found")]
+    #[diagnostic(code(arbiter::evm::sign::wallet_not_found))]
     WalletNotFound,
 
     #[error("Database error: {0}")]
-    Database(#[from] DatabaseError),
+    #[diagnostic(code(arbiter::evm::sign::database))]
+    Database(#[from] diesel::result::Error),
 
-    #[error("Vault error: {0}")]
-    Vault(#[from] crate::actors::vault::Error),
+    #[error("Database pool error: {0}")]
+    #[diagnostic(code(arbiter::evm::sign::pool))]
+    Pool(#[from] db::PoolError),
 
-    #[error("Vault mailbox error")]
-    VaultSend,
+    #[error("Keyholder error: {0}")]
+    #[diagnostic(code(arbiter::evm::sign::keyholder))]
+    Keyholder(#[from] crate::actors::keyholder::Error),
+
+    #[error("Keyholder mailbox error")]
+    #[diagnostic(code(arbiter::evm::sign::keyholder_send))]
+    KeyholderSend,
 
     #[error("Signing error: {0}")]
+    #[diagnostic(code(arbiter::evm::sign::signing))]
     Signing(#[from] alloy::signers::Error),
 
     #[error("Policy error: {0}")]
+    #[diagnostic(code(arbiter::evm::sign::vet))]
     Vet(#[from] evm::VetError),
 }
 
-#[derive(Debug, thiserror::Error)]
+#[derive(Debug, thiserror::Error, miette::Diagnostic)]
 pub enum Error {
-    #[error("Vault error: {0}")]
-    Vault(#[from] crate::actors::vault::Error),
+    #[error("Keyholder error: {0}")]
+    #[diagnostic(code(arbiter::evm::keyholder))]
+    Keyholder(#[from] crate::actors::keyholder::Error),
 
-    #[error("Vault mailbox error")]
-    VaultSend,
+    #[error("Keyholder mailbox error")]
+    #[diagnostic(code(arbiter::evm::keyholder_send))]
+    KeyholderSend,
 
     #[error("Database error: {0}")]
-    Database(#[from] DatabaseError),
+    #[diagnostic(code(arbiter::evm::database))]
+    Database(#[from] diesel::result::Error),
 
-    #[error("Integrity violation: {0}")]
-    Integrity(#[from] integrity::Error),
+    #[error("Database pool error: {0}")]
+    #[diagnostic(code(arbiter::evm::database_pool))]
+    DatabasePool(#[from] db::PoolError),
 
-    #[error("Signing error: {0}")]
-    Sign(#[from] SignTransactionError),
-
-    #[error(
-        "Grant timestamp {0} is outside the i32 range a grant boundary column can store \
-         (Unix seconds, so no later than 2038-01-19T03:14:07Z)"
-    )]
-    InvalidTimestamp(i64),
-
-    #[error("Wallet access {0} is revoked or does not exist")]
-    AccessNotActive(i32),
-}
-
-/// Converts a grant boundary from Unix seconds. `None` in means "unbounded"; a value the
-/// boundary column cannot store is an error, never a silently different window.
-///
-/// The range is `i32`, not `i64`, because that is what actually reaches the database:
-/// `SqliteTimestamp::to_sql` narrows to `i32` (`fixme! #84`), so `3_000_000_000` -- a
-/// `valid_from` in 2065 -- would wrap to 1902 and open the grant immediately instead of in
-/// forty years. Accepting only what round-trips keeps the grant that gets written the grant
-/// that was voted on.
-fn grant_timestamp(secs: Option<i64>) -> Result<Option<chrono::DateTime<chrono::Utc>>, Error> {
-    secs.map(|s| {
-        let storable = i32::try_from(s).map_err(|_| Error::InvalidTimestamp(s))?;
-        chrono::DateTime::from_timestamp(i64::from(storable), 0).ok_or(Error::InvalidTimestamp(s))
-    })
-    .transpose()
-}
-
-/// Refuses an access id that is revoked or absent, so nothing hangs a grant off it.
-async fn ensure_access_active(
-    conn: &mut crate::db::DatabaseConnection,
-    access_id: i32,
-) -> Result<(), Error> {
-    let active: bool = diesel::select(diesel::dsl::exists(
-        schema::evm_wallet_access::table
-            .filter(schema::evm_wallet_access::id.eq(access_id))
-            .filter(schema::evm_wallet_access::revoked_at.is_null()),
-    ))
-    .get_result(conn)
-    .await
-    .map_err(DatabaseError::from)?;
-
-    if active {
-        Ok(())
-    } else {
-        Err(Error::AccessNotActive(access_id))
-    }
+    #[error("Grant creation error: {0}")]
+    #[diagnostic(code(arbiter::evm::creation))]
+    Creation(#[from] evm::CreationError),
 }
 
 #[derive(Actor)]
 pub struct EvmActor {
-    pub vault: ActorRef<Vault>,
+    pub keyholder: ActorRef<KeyHolder>,
     pub db: DatabasePool,
     pub rng: StdRng,
     pub engine: evm::Engine,
 }
 
 impl EvmActor {
-    pub fn new(vault: ActorRef<Vault>, db: DatabasePool) -> Self {
+    pub fn new(keyholder: ActorRef<KeyHolder>, db: DatabasePool) -> Self {
         // is it safe to seed rng from system once?
         // todo: audit
         let rng = StdRng::from_rng(&mut rng());
-        let engine = evm::Engine::new(db.clone(), vault.clone());
+        let engine = evm::Engine::new(db.clone());
         Self {
-            vault,
+            keyholder,
             db,
             rng,
             engine,
@@ -144,43 +105,40 @@ impl EvmActor {
 #[messages]
 impl EvmActor {
     #[message]
-    pub async fn generate(&mut self) -> Result<(i32, Address), Error> {
+    pub async fn generate(&mut self) -> Result<Address, Error> {
         let (mut key_cell, address) = safe_signer::generate(&mut self.rng);
 
         let plaintext = key_cell.read_inline(|reader| SafeCell::new(reader.to_vec()));
 
         let aead_id: i32 = self
-            .vault
+            .keyholder
             .ask(CreateNew { plaintext })
             .await
-            .map_err(|_| Error::VaultSend)?;
+            .map_err(|_| Error::KeyholderSend)?;
 
-        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
-        let wallet_id = insert_into(schema::evm_wallet::table)
+        let mut conn = self.db.get().await?;
+        insert_into(schema::evm_wallet::table)
             .values(&models::NewEvmWallet {
                 address: address.as_slice().to_vec(),
                 aead_encrypted_id: aead_id,
             })
-            .returning(schema::evm_wallet::id)
-            .get_result(&mut conn)
-            .await
-            .map_err(DatabaseError::from)?;
+            .execute(&mut conn)
+            .await?;
 
-        Ok((wallet_id, address))
+        Ok(address)
     }
 
     #[message]
-    pub async fn list_wallets(&self) -> Result<Vec<(EvmWalletId, Address)>, Error> {
-        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
+    pub async fn list_wallets(&self) -> Result<Vec<Address>, Error> {
+        let mut conn = self.db.get().await?;
         let rows: Vec<models::EvmWallet> = schema::evm_wallet::table
             .select(models::EvmWallet::as_select())
             .load(&mut conn)
-            .await
-            .map_err(DatabaseError::from)?;
+            .await?;
 
         Ok(rows
             .into_iter()
-            .map(|w| (w.id, Address::from_slice(&w.address)))
+            .map(|w| Address::from_slice(&w.address))
             .collect())
     }
 }
@@ -188,57 +146,55 @@ impl EvmActor {
 #[messages]
 impl EvmActor {
     #[message]
-    pub async fn operator_create_grant(
+    pub async fn useragent_create_grant(
         &mut self,
+        client_id: i32,
         basic: SharedGrantSettings,
         grant: SpecificGrant,
-    ) -> Result<i32, Error> {
+    ) -> Result<i32, evm::CreationError> {
         match grant {
-            SpecificGrant::EtherTransfer(settings) => self
-                .engine
-                .create_grant::<EtherTransfer>(CombinedSettings {
-                    shared: basic,
+            SpecificGrant::EtherTransfer(settings) => {
+                self.engine
+                    .create_grant::<EtherTransfer>(
+                        client_id,
+                        FullGrant {
+                            basic,
                             specific: settings,
-                })
+                        },
+                    )
                     .await
-                .map_err(Error::from),
-            SpecificGrant::TokenTransfer(settings) => self
-                .engine
-                .create_grant::<TokenTransfer>(CombinedSettings {
-                    shared: basic,
+            }
+            SpecificGrant::TokenTransfer(settings) => {
+                self.engine
+                    .create_grant::<TokenTransfer>(
+                        client_id,
+                        FullGrant {
+                            basic,
                             specific: settings,
-                })
+                        },
+                    )
                     .await
-                .map_err(Error::from),
+            }
         }
     }
 
     #[message]
-    pub async fn operator_delete_grant(&mut self, grant_id: i32) -> Result<(), Error> {
-        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
-
-        let affected = diesel::update(schema::evm_basic_grant::table)
+    pub async fn useragent_delete_grant(&mut self, grant_id: i32) -> Result<(), Error> {
+        let mut conn = self.db.get().await?;
+        diesel::update(schema::evm_basic_grant::table)
             .filter(schema::evm_basic_grant::id.eq(grant_id))
-            .set(schema::evm_basic_grant::revoked_at.eq(models::SqliteTimestamp::now()))
+            .set(schema::evm_basic_grant::revoked_at.eq(SqliteTimestamp::now()))
             .execute(&mut conn)
-            .await
-            .map_err(DatabaseError::from)?;
-
-        if affected == 0 {
-            return Err(Error::Database(DatabaseError::from(
-                diesel::result::Error::NotFound,
-            )));
-        }
-
+            .await?;
         Ok(())
     }
 
     #[message]
-    pub async fn operator_list_grants(&mut self) -> Result<Vec<Grant<SpecificGrant>>, Error> {
+    pub async fn useragent_list_grants(&mut self) -> Result<Vec<Grant<SpecificGrant>>, Error> {
         match self.engine.list_all_grants().await {
             Ok(grants) => Ok(grants),
-            Err(ListError::Database(db_err)) => Err(Error::Database(db_err)),
-            Err(ListError::Integrity(integrity_err)) => Err(Error::Integrity(integrity_err)),
+            Err(ListGrantsError::Database(db)) => Err(Error::Database(db)),
+            Err(ListGrantsError::Pool(pool)) => Err(Error::DatabasePool(pool)),
         }
     }
 
@@ -249,30 +205,24 @@ impl EvmActor {
         wallet_address: Address,
         transaction: TxEip1559,
     ) -> Result<SpecificMeaning, SignTransactionError> {
-        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
+        let mut conn = self.db.get().await?;
         let wallet = schema::evm_wallet::table
             .select(models::EvmWallet::as_select())
             .filter(schema::evm_wallet::address.eq(wallet_address.as_slice()))
             .first(&mut conn)
             .await
-            .optional()
-            .map_err(DatabaseError::from)?
-            .ok_or(SignTransactionError::WalletNotFound)?;
-        let wallet_access = schema::evm_wallet_access::table
-            .select(models::EvmWalletAccess::as_select())
-            .filter(schema::evm_wallet_access::wallet_id.eq(wallet.id))
-            .filter(schema::evm_wallet_access::client_id.eq(client_id))
-            .filter(schema::evm_wallet_access::revoked_at.is_null())
-            .first(&mut conn)
-            .await
-            .optional()
-            .map_err(DatabaseError::from)?
+            .optional()?
             .ok_or(SignTransactionError::WalletNotFound)?;
         drop(conn);
 
         let meaning = self
             .engine
-            .evaluate_transaction(wallet_access, transaction.clone(), RunKind::Execution)
+            .evaluate_transaction(
+                wallet.id,
+                client_id,
+                transaction.clone(),
+                RunKind::Execution,
+            )
             .await?;
 
         Ok(meaning)
@@ -285,410 +235,36 @@ impl EvmActor {
         wallet_address: Address,
         mut transaction: TxEip1559,
     ) -> Result<Signature, SignTransactionError> {
-        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
+        let mut conn = self.db.get().await?;
         let wallet = schema::evm_wallet::table
             .select(models::EvmWallet::as_select())
             .filter(schema::evm_wallet::address.eq(wallet_address.as_slice()))
             .first(&mut conn)
             .await
-            .optional()
-            .map_err(DatabaseError::from)?
-            .ok_or(SignTransactionError::WalletNotFound)?;
-        let wallet_access = schema::evm_wallet_access::table
-            .select(models::EvmWalletAccess::as_select())
-            .filter(schema::evm_wallet_access::wallet_id.eq(wallet.id))
-            .filter(schema::evm_wallet_access::client_id.eq(client_id))
-            .filter(schema::evm_wallet_access::revoked_at.is_null())
-            .first(&mut conn)
-            .await
-            .optional()
-            .map_err(DatabaseError::from)?
+            .optional()?
             .ok_or(SignTransactionError::WalletNotFound)?;
         drop(conn);
 
         let raw_key: SafeCell<Vec<u8>> = self
-            .vault
+            .keyholder
             .ask(Decrypt {
                 aead_id: wallet.aead_encrypted_id,
             })
             .await
-            .map_err(|_| SignTransactionError::VaultSend)?;
+            .map_err(|_| SignTransactionError::KeyholderSend)?;
 
         let signer = safe_signer::SafeSigner::from_cell(raw_key)?;
 
         self.engine
-            .evaluate_transaction(wallet_access, transaction.clone(), RunKind::Execution)
+            .evaluate_transaction(
+                wallet.id,
+                client_id,
+                transaction.clone(),
+                RunKind::Execution,
+            )
             .await?;
 
+        use alloy::network::TxSignerSync as _;
         Ok(signer.sign_transaction_sync(&mut transaction)?)
     }
 }
-
-impl Message<ProposalApproved> for EvmActor {
-    type Reply = ();
-
-    /// Every subscriber sees every approval and acts only on the kinds it owns.
-    async fn handle(
-        &mut self,
-        msg: ProposalApproved,
-        _ctx: &mut kameo::prelude::Context<Self, Self::Reply>,
-    ) -> Self::Reply {
-        let result = match msg.kind {
-            ProposalKind::GrantWalletAccess(settings) => self.grant_wallet_access(&settings).await,
-            ProposalKind::ApprovePersistentGrant(settings) => {
-                self.create_persistent_grant(*settings).await
-            }
-            ProposalKind::ApproveOneOffTransaction(settings) => {
-                self.sign_one_off_transaction(msg.id, *settings).await
-            }
-            _ => return,
-        };
-
-        if let Err(error) = result {
-            error!(
-                ?error,
-                proposal_id = msg.id.to_raw(),
-                "Failed to execute an approved proposal"
-            );
-        }
-    }
-}
-
-impl EvmActor {
-    async fn grant_wallet_access(
-        &mut self,
-        settings: &grant_wallet_access::Settings,
-    ) -> Result<(), Error> {
-        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
-
-        // Revives a previously revoked row instead of conflicting on it forever:
-        // `uniq_wallet_access` is a unique index on `(wallet_id, client_id)`. Visibility is
-        // all this restores -- revocation closes the grants that hung off the access, so a
-        // persistent grant needs its own vote again (§3.2). See
-        // `peers::operator::session::handlers::revoke_wallet_access`.
-        insert_into(schema::evm_wallet_access::table)
-            .values((
-                schema::evm_wallet_access::wallet_id.eq(EvmWalletId::from_raw(settings.wallet_id)),
-                schema::evm_wallet_access::client_id.eq(settings.client_id),
-            ))
-            .on_conflict((
-                schema::evm_wallet_access::wallet_id,
-                schema::evm_wallet_access::client_id,
-            ))
-            .do_update()
-            .set(schema::evm_wallet_access::revoked_at.eq(None::<models::SqliteTimestamp>))
-            .execute(&mut conn)
-            .await
-            .map_err(DatabaseError::from)?;
-
-        Ok(())
-    }
-
-    async fn create_persistent_grant(
-        &mut self,
-        grant: persistent_grant::Settings,
-    ) -> Result<(), Error> {
-        use crate::evm::policies::{
-            TransactionRateLimit, VolumeRateLimit, ether_transfer, token_transfers,
-        };
-        use alloy::primitives::U256;
-        use chrono::Duration;
-
-        // A persistent grant is only as good as the visibility it hangs off (§3.2, two
-        // separate votes). The proposal names the access id when it is created and can be
-        // approved much later, so the access may have been revoked in between; a grant
-        // against a revoked access would sit dormant and go live the moment anyone re-grants.
-        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
-        ensure_access_active(&mut conn, grant.wallet_access_id).await?;
-        drop(conn);
-
-        let volume = |limit: persistent_grant::VolumeLimit| VolumeRateLimit {
-            max_volume: U256::from_be_bytes(limit.max_volume),
-            window: Duration::seconds(limit.window_secs),
-        };
-
-        let basic = SharedGrantSettings {
-            wallet_access_id: grant.wallet_access_id,
-            chain: grant.chain_id,
-            valid_from: grant_timestamp(grant.valid_from_secs)?,
-            valid_until: grant_timestamp(grant.valid_until_secs)?,
-            max_gas_fee_per_gas: grant.max_gas_fee_per_gas.map(U256::from_be_bytes),
-            max_priority_fee_per_gas: grant.max_priority_fee_per_gas.map(U256::from_be_bytes),
-            rate_limit: grant.rate_limit.map(|r| TransactionRateLimit {
-                count: r.count,
-                window: Duration::seconds(r.window_secs),
-            }),
-        };
-
-        let specific = match grant.specific {
-            persistent_grant::Specific::EtherTransfer { targets, limit } => {
-                SpecificGrant::EtherTransfer(ether_transfer::Settings {
-                    target: targets.into_iter().map(Address::from).collect(),
-                    limit: volume(limit),
-                })
-            }
-            persistent_grant::Specific::TokenTransfer {
-                token_contract,
-                receiver,
-                volume_limits,
-            } => SpecificGrant::TokenTransfer(token_transfers::Settings {
-                token_contract: Address::from(token_contract),
-                target: receiver.map(Address::from),
-                volume_limits: volume_limits.into_iter().map(volume).collect(),
-            }),
-        };
-
-        self.operator_create_grant(basic, specific).await?;
-
-        Ok(())
-    }
-
-    async fn sign_one_off_transaction(
-        &mut self,
-        proposal_id: ProposalId,
-        tx: one_off_transaction::Settings,
-    ) -> Result<(), Error> {
-        use alloy::{
-            eips::eip2930::AccessList,
-            primitives::{Bytes, TxKind, U256},
-        };
-
-        let transaction = TxEip1559 {
-            chain_id: tx.chain_id,
-            nonce: tx.nonce,
-            gas_limit: tx.gas_limit,
-            max_fee_per_gas: tx.max_fee_per_gas,
-            max_priority_fee_per_gas: tx.max_priority_fee_per_gas,
-            to: TxKind::Call(Address::from(tx.to)),
-            value: U256::from_be_bytes(tx.value),
-            input: Bytes::from(tx.input),
-            access_list: AccessList::default(),
-        };
-
-        let signature = self
-            .client_sign_transaction(tx.client_id, Address::from(tx.wallet_address), transaction)
-            .await?;
-
-        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
-        one_off_transaction::store_signature(proposal_id, &signature, &mut conn)
-            .await
-            .map_err(DatabaseError::from)?;
-
-        Ok(())
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::{Error, EvmActor, ensure_access_active, grant_timestamp};
-    use crate::db::{self, models, schema};
-
-    use diesel::{ExpressionMethods as _, QueryDsl as _, dsl::insert_into};
-    use diesel_async::RunQueryDsl;
-
-    #[test]
-    fn absent_timestamp_stays_absent() {
-        assert!(grant_timestamp(None).unwrap().is_none());
-    }
-
-    #[test]
-    fn in_range_timestamp_is_converted() {
-        let converted = grant_timestamp(Some(1_800_000_000)).unwrap();
-        assert_eq!(converted.unwrap().timestamp(), 1_800_000_000);
-    }
-
-    /// An unrepresentable expiry must not silently become "no expiry": that would widen the
-    /// grant beyond what was voted on.
-    #[test]
-    fn out_of_range_timestamp_is_an_error() {
-        let err = grant_timestamp(Some(i64::MAX)).unwrap_err();
-        assert!(matches!(err, Error::InvalidTimestamp(i64::MAX)));
-    }
-
-    /// A `valid_from` past 2038 is representable as a `DateTime` but not as the `i32` the
-    /// boundary column stores: `3_000_000_000` (2065) wraps to a negative, which reads back as
-    /// 1902 and makes the grant active immediately. Refusing it is the only way the grant
-    /// that lands can match the window that was voted on.
-    #[test]
-    fn a_timestamp_past_2038_is_an_error() {
-        let past_2038 = 3_000_000_000_i64;
-        assert!(
-            chrono::DateTime::from_timestamp(past_2038, 0).is_some(),
-            "the fixture must be a date chrono accepts, or it proves nothing about storage"
-        );
-
-        let err = grant_timestamp(Some(past_2038)).unwrap_err();
-        assert!(
-            matches!(err, Error::InvalidTimestamp(got) if got == past_2038),
-            "expected an out-of-range error, got {err:?}"
-        );
-    }
-
-    /// The last second the boundary column can hold must still be accepted: the range check
-    /// has to stop at what storage can take, not short of it.
-    #[test]
-    fn the_last_storable_timestamp_is_accepted() {
-        let converted = grant_timestamp(Some(i64::from(i32::MAX))).unwrap();
-        assert_eq!(converted.unwrap().timestamp(), i64::from(i32::MAX));
-    }
-
-    /// Seeds a wallet, a client and one access row between them, and returns the access id.
-    async fn seed_access(conn: &mut db::DatabaseConnection) -> i32 {
-        let root_key_id: models::RootKeyHistoryId = insert_into(schema::root_key_history::table)
-            .values(&models::NewRootKeyHistory {
-                ciphertext: vec![0u8; 32],
-                tag: vec![0u8; 16],
-                root_key_encryption_nonce: vec![0u8; 24],
-                data_encryption_nonce: vec![0u8; 24],
-                schema_version: 1,
-                salt: vec![0u8; 16],
-            })
-            .returning(schema::root_key_history::id)
-            .get_result(conn)
-            .await
-            .unwrap();
-
-        let aead_id: i32 = insert_into(schema::aead_encrypted::table)
-            .values(&models::NewAeadEncrypted {
-                ciphertext: vec![0u8; 32],
-                tag: vec![0u8; 16],
-                current_nonce: vec![0u8; 24],
-                schema_version: 1,
-                associated_root_key_id: root_key_id,
-                created_at: chrono::Utc::now().into(),
-            })
-            .returning(schema::aead_encrypted::id)
-            .get_result(conn)
-            .await
-            .unwrap();
-
-        let wallet_id: models::EvmWalletId = insert_into(schema::evm_wallet::table)
-            .values((
-                schema::evm_wallet::address.eq(rand::random::<[u8; 20]>().to_vec()),
-                schema::evm_wallet::aead_encrypted_id.eq(aead_id),
-            ))
-            .returning(schema::evm_wallet::id)
-            .get_result(conn)
-            .await
-            .unwrap();
-
-        let metadata_id: i32 = insert_into(schema::client_metadata::table)
-            .values(schema::client_metadata::name.eq("test"))
-            .returning(schema::client_metadata::id)
-            .get_result(conn)
-            .await
-            .unwrap();
-
-        let client_id: i32 = insert_into(schema::program_client::table)
-            .values((
-                schema::program_client::public_key.eq(rand::random::<[u8; 32]>().to_vec()),
-                schema::program_client::metadata_id.eq(metadata_id),
-            ))
-            .returning(schema::program_client::id)
-            .get_result(conn)
-            .await
-            .unwrap();
-
-        insert_into(schema::evm_wallet_access::table)
-            .values((
-                schema::evm_wallet_access::wallet_id.eq(wallet_id),
-                schema::evm_wallet_access::client_id.eq(client_id),
-            ))
-            .returning(schema::evm_wallet_access::id)
-            .get_result(conn)
-            .await
-            .unwrap()
-    }
-
-    /// Both directions, so a guard that refused everything could not pass: a live access is
-    /// let through, a revoked one is not.
-    #[tokio::test]
-    async fn only_a_live_access_passes_the_grant_guard() {
-        let pool = db::create_test_pool().await;
-        let mut conn = pool.get().await.unwrap();
-
-        let access_id = seed_access(&mut conn).await;
-        ensure_access_active(&mut conn, access_id)
-            .await
-            .expect("a live access must pass");
-
-        diesel::update(schema::evm_wallet_access::table)
-            .filter(schema::evm_wallet_access::id.eq(access_id))
-            .set(schema::evm_wallet_access::revoked_at.eq(models::SqliteTimestamp::now()))
-            .execute(&mut conn)
-            .await
-            .unwrap();
-
-        let err = ensure_access_active(&mut conn, access_id)
-            .await
-            .expect_err("a revoked access must be refused");
-        assert!(
-            matches!(err, Error::AccessNotActive(got) if got == access_id),
-            "expected AccessNotActive, got {err:?}"
-        );
-    }
-
-    /// The guard has to be wired into the executor, not just exist: an approved persistent
-    /// grant whose access was revoked between proposal and approval must not create a grant
-    /// that would go live again the moment anyone re-grants that access (§3.2).
-    #[tokio::test]
-    async fn an_approved_persistent_grant_refuses_a_revoked_access() {
-        use crate::actors::{GlobalActors, vault::Vault};
-        use crate::db::proposal::persistent_grant;
-        use kameo::actor::Spawn as _;
-
-        let pool = db::create_test_pool().await;
-        let mut conn = pool.get().await.unwrap();
-
-        let access_id = seed_access(&mut conn).await;
-        diesel::update(schema::evm_wallet_access::table)
-            .filter(schema::evm_wallet_access::id.eq(access_id))
-            .set(schema::evm_wallet_access::revoked_at.eq(models::SqliteTimestamp::now()))
-            .execute(&mut conn)
-            .await
-            .unwrap();
-        drop(conn);
-
-        let vault = Vault::spawn(
-            Vault::new(pool.clone(), GlobalActors::spawn_message_bus())
-                .await
-                .unwrap(),
-        );
-        let mut evm_actor = EvmActor::new(vault, pool.clone());
-
-        let err = evm_actor
-            .create_persistent_grant(persistent_grant::Settings {
-                wallet_access_id: access_id,
-                chain_id: 1,
-                valid_from_secs: None,
-                valid_until_secs: None,
-                max_gas_fee_per_gas: None,
-                max_priority_fee_per_gas: None,
-                rate_limit: None,
-                specific: persistent_grant::Specific::EtherTransfer {
-                    targets: vec![[0u8; 20]],
-                    limit: persistent_grant::VolumeLimit {
-                        max_volume: [0u8; 32],
-                        window_secs: 3600,
-                    },
-                },
-            })
-            .await
-            .expect_err("a grant against a revoked access must be refused");
-        assert!(
-            matches!(err, Error::AccessNotActive(got) if got == access_id),
-            "expected AccessNotActive, got {err:?}"
-        );
-
-        let grants: i64 = schema::evm_basic_grant::table
-            .filter(schema::evm_basic_grant::wallet_access_id.eq(access_id))
-            .count()
-            .get_result(&mut pool.get().await.unwrap())
-            .await
-            .unwrap();
-        assert_eq!(
-            grants, 0,
-            "no grant row may be written for a revoked access"
-        );
-    }
-}

server/crates/arbiter-server/src/actors/flow_coordinator/client_connect_approval.rs

@@ -1,107 +0,0 @@
-use crate::{
-    actors::flow_coordinator::ApprovalError,
-    peers::{
-        client::ClientProfile,
-        operator::{OperatorSession, session::BeginNewClientApproval},
-    },
-};
-
-use kameo::{
-    Actor, messages,
-    prelude::{ActorId, ActorRef, ActorStopReason, Context, WeakActorRef},
-    reply::ReplySender,
-};
-use std::ops::ControlFlow;
-
-pub struct Args {
-    pub client: ClientProfile,
-    pub operators: Vec<ActorRef<OperatorSession>>,
-    pub reply: ReplySender<Result<bool, ApprovalError>>,
-}
-
-pub struct ClientApprovalController {
-    /// Number of operators that have not yet responded (approval or denial) or died.
-    pending: usize,
-    /// Number of approvals received so far.
-    approved: usize,
-    reply: Option<ReplySender<Result<bool, ApprovalError>>>,
-}
-
-impl ClientApprovalController {
-    fn send_reply(&mut self, result: Result<bool, ApprovalError>) {
-        if let Some(reply) = self.reply.take() {
-            reply.send(result);
-        }
-    }
-}
-
-impl Actor for ClientApprovalController {
-    type Args = Args;
-    type Error = ();
-
-    async fn on_start(
-        Args {
-            client,
-            operators,
-            reply,
-        }: Self::Args,
-        actor_ref: ActorRef<Self>,
-    ) -> Result<Self, Self::Error> {
-        let this = Self {
-            pending: operators.len(),
-            approved: 0,
-            reply: Some(reply),
-        };
-
-        for operator in operators {
-            actor_ref.link(&operator).await;
-
-            let _ = operator
-                .tell(BeginNewClientApproval {
-                    client: client.clone(),
-                    controller: actor_ref.clone(),
-                })
-                .await;
-        }
-
-        Ok(this)
-    }
-
-    async fn on_link_died(
-        &mut self,
-        _: WeakActorRef<Self>,
-        _: ActorId,
-        _: ActorStopReason,
-    ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
-        // A linked operator died before responding — counts as a non-approval.
-        self.pending = self.pending.saturating_sub(1);
-        if self.pending == 0 {
-            // At least one operator didn't approve: deny.
-            self.send_reply(Ok(false));
-            return Ok(ControlFlow::Break(ActorStopReason::Normal));
-        }
-        Ok(ControlFlow::Continue(()))
-    }
-}
-
-#[messages]
-impl ClientApprovalController {
-    #[message(ctx)]
-    pub fn client_approval_answer(&mut self, approved: bool, ctx: &mut Context<Self, ()>) {
-        if !approved {
-            // Denial wins immediately regardless of other pending responses.
-            self.send_reply(Ok(false));
-            ctx.stop();
-            return;
-        }
-
-        self.approved += 1;
-        self.pending = self.pending.saturating_sub(1);
-
-        if self.pending == 0 {
-            // Every connected operator approved.
-            self.send_reply(Ok(true));
-            ctx.stop();
-        }
-    }
-}

server/crates/arbiter-server/src/actors/flow_coordinator/mod.rs

@@ -1,114 +0,0 @@
-use crate::{
-    actors::{
-        flow_coordinator::client_connect_approval::ClientApprovalController,
-        operator_registry::{GetConnected, OperatorRegistry},
-    },
-    peers::client::{ClientProfile, session::ClientSession},
-};
-
-use kameo::{
-    Actor,
-    actor::{ActorId, ActorRef, Spawn},
-    messages,
-    prelude::{ActorStopReason, Context, WeakActorRef},
-    reply::DelegatedReply,
-};
-use std::{collections::HashMap, ops::ControlFlow};
-use tracing::info;
-
-pub mod client_connect_approval;
-
-pub struct FlowCoordinator {
-    pub clients: HashMap<ActorId, ActorRef<ClientSession>>,
-    operator_registry: ActorRef<OperatorRegistry>,
-}
-
-impl FlowCoordinator {
-    pub fn new(operator_registry: ActorRef<OperatorRegistry>) -> Self {
-        Self {
-            clients: HashMap::default(),
-            operator_registry,
-        }
-    }
-}
-
-impl Actor for FlowCoordinator {
-    type Args = Self;
-
-    type Error = ();
-
-    async fn on_start(args: Self::Args, _: ActorRef<Self>) -> Result<Self, Self::Error> {
-        Ok(args)
-    }
-
-    async fn on_link_died(
-        &mut self,
-        _: WeakActorRef<Self>,
-        id: ActorId,
-        _: ActorStopReason,
-    ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
-        if self.clients.remove(&id).is_some() {
-            info!(
-                ?id,
-                actor = "FlowCoordinator",
-                event = "client.disconnected"
-            );
-        } else {
-            info!(
-                ?id,
-                actor = "FlowCoordinator",
-                event = "unknown.actor.disconnected"
-            );
-        }
-        Ok(ControlFlow::Continue(()))
-    }
-}
-
-#[derive(Debug, thiserror::Error, Clone, PartialEq, Eq, Hash)]
-pub enum ApprovalError {
-    #[error("No operators connected")]
-    NoOperatorsConnected,
-}
-
-#[messages]
-impl FlowCoordinator {
-    #[message(ctx)]
-    pub async fn register_client(
-        &mut self,
-        actor: ActorRef<ClientSession>,
-        ctx: &mut Context<Self, ()>,
-    ) {
-        info!(id = %actor.id(), actor = "FlowCoordinator", event = "client.connected");
-        ctx.actor_ref().link(&actor).await;
-        self.clients.insert(actor.id(), actor);
-    }
-
-    #[message(ctx)]
-    pub async fn request_client_approval(
-        &mut self,
-        client: ClientProfile,
-        ctx: &mut Context<Self, DelegatedReply<Result<bool, ApprovalError>>>,
-    ) -> DelegatedReply<Result<bool, ApprovalError>> {
-        let (reply, Some(reply_sender)) = ctx.reply_sender() else {
-            unreachable!("Expected `request_client_approval` to have callback channel");
-        };
-
-        let Ok(refs) = self.operator_registry.ask(GetConnected).await else {
-            reply_sender.send(Err(ApprovalError::NoOperatorsConnected));
-            return reply;
-        };
-
-        if refs.is_empty() {
-            reply_sender.send(Err(ApprovalError::NoOperatorsConnected));
-            return reply;
-        }
-
-        ClientApprovalController::spawn(client_connect_approval::Args {
-            client,
-            operators: refs,
-            reply: reply_sender,
-        });
-
-        reply
-    }
-}

server/crates/arbiter-server/src/actors/keyholder/encryption.rs

@@ -0,0 +1 @@
+pub mod v1;

server/crates/arbiter-server/src/actors/keyholder/encryption/v1.rs

@@ -0,0 +1,243 @@
+use std::ops::Deref as _;
+
+use argon2::{Algorithm, Argon2, password_hash::Salt as ArgonSalt};
+use chacha20poly1305::{
+    AeadInPlace, Key, KeyInit as _, XChaCha20Poly1305, XNonce,
+    aead::{AeadMut, Error, Payload},
+};
+use rand::{
+    Rng as _, SeedableRng,
+    rngs::{StdRng, SysRng},
+};
+
+use crate::safe_cell::{SafeCell, SafeCellHandle as _};
+
+pub const ROOT_KEY_TAG: &[u8] = "arbiter/seal/v1".as_bytes();
+pub const TAG: &[u8] = "arbiter/private-key/v1".as_bytes();
+
+pub const NONCE_LENGTH: usize = 24;
+
+#[derive(Default)]
+pub struct Nonce([u8; NONCE_LENGTH]);
+impl Nonce {
+    pub fn increment(&mut self) {
+        for i in (0..self.0.len()).rev() {
+            if self.0[i] == 0xFF {
+                self.0[i] = 0;
+            } else {
+                self.0[i] += 1;
+                break;
+            }
+        }
+    }
+
+    pub fn to_vec(&self) -> Vec<u8> {
+        self.0.to_vec()
+    }
+}
+impl<'a> TryFrom<&'a [u8]> for Nonce {
+    type Error = ();
+
+    fn try_from(value: &'a [u8]) -> Result<Self, Self::Error> {
+        if value.len() != NONCE_LENGTH {
+            return Err(());
+        }
+        let mut nonce = [0u8; NONCE_LENGTH];
+        nonce.copy_from_slice(value);
+        Ok(Self(nonce))
+    }
+}
+
+pub struct KeyCell(pub SafeCell<Key>);
+impl From<SafeCell<Key>> for KeyCell {
+    fn from(value: SafeCell<Key>) -> Self {
+        Self(value)
+    }
+}
+impl TryFrom<SafeCell<Vec<u8>>> for KeyCell {
+    type Error = ();
+
+    fn try_from(mut value: SafeCell<Vec<u8>>) -> Result<Self, Self::Error> {
+        let value = value.read();
+        if value.len() != size_of::<Key>() {
+            return Err(());
+        }
+        let cell = SafeCell::new_inline(|cell_write: &mut Key| {
+            cell_write.copy_from_slice(&value);
+        });
+        Ok(Self(cell))
+    }
+}
+
+impl KeyCell {
+    pub fn new_secure_random() -> Self {
+        let key = SafeCell::new_inline(|key_buffer: &mut Key| {
+            #[allow(
+                clippy::unwrap_used,
+                reason = "Rng failure is unrecoverable and should panic"
+            )]
+            let mut rng = StdRng::try_from_rng(&mut SysRng).unwrap();
+            rng.fill_bytes(key_buffer);
+        });
+
+        key.into()
+    }
+
+    pub fn encrypt_in_place(
+        &mut self,
+        nonce: &Nonce,
+        associated_data: &[u8],
+        mut buffer: impl AsMut<Vec<u8>>,
+    ) -> Result<(), Error> {
+        let key_reader = self.0.read();
+        let key_ref = key_reader.deref();
+        let cipher = XChaCha20Poly1305::new(key_ref);
+        let nonce = XNonce::from_slice(nonce.0.as_ref());
+        let buffer = buffer.as_mut();
+        cipher.encrypt_in_place(nonce, associated_data, buffer)
+    }
+    pub fn decrypt_in_place(
+        &mut self,
+        nonce: &Nonce,
+        associated_data: &[u8],
+        buffer: &mut SafeCell<Vec<u8>>,
+    ) -> Result<(), Error> {
+        let key_reader = self.0.read();
+        let key_ref = key_reader.deref();
+        let cipher = XChaCha20Poly1305::new(key_ref);
+        let nonce = XNonce::from_slice(nonce.0.as_ref());
+        let mut buffer = buffer.write();
+        let buffer: &mut Vec<u8> = buffer.as_mut();
+        cipher.decrypt_in_place(nonce, associated_data, buffer)
+    }
+
+    pub fn encrypt(
+        &mut self,
+        nonce: &Nonce,
+        associated_data: &[u8],
+        plaintext: impl AsRef<[u8]>,
+    ) -> Result<Vec<u8>, Error> {
+        let key_reader = self.0.read();
+        let key_ref = key_reader.deref();
+        let mut cipher = XChaCha20Poly1305::new(key_ref);
+        let nonce = XNonce::from_slice(nonce.0.as_ref());
+
+        let ciphertext = cipher.encrypt(
+            nonce,
+            Payload {
+                msg: plaintext.as_ref(),
+                aad: associated_data,
+            },
+        )?;
+        Ok(ciphertext)
+    }
+}
+
+pub type Salt = [u8; ArgonSalt::RECOMMENDED_LENGTH];
+
+pub fn generate_salt() -> Salt {
+    let mut salt = Salt::default();
+    #[allow(
+        clippy::unwrap_used,
+        reason = "Rng failure is unrecoverable and should panic"
+    )]
+    let mut rng = StdRng::try_from_rng(&mut SysRng).unwrap();
+    rng.fill_bytes(&mut salt);
+    salt
+}
+
+/// User password might be of different length, have not enough entropy, etc...
+/// Derive a fixed-length key from the password using Argon2id, which is designed for password hashing and key derivation.
+pub fn derive_seal_key(mut password: SafeCell<Vec<u8>>, salt: &Salt) -> KeyCell {
+    #[allow(clippy::unwrap_used)]
+    let params = argon2::Params::new(262_144, 3, 4, None).unwrap();
+    let hasher = Argon2::new(Algorithm::Argon2id, argon2::Version::V0x13, params);
+    let mut key = SafeCell::new(Key::default());
+    password.read_inline(|password_source| {
+        let mut key_buffer = key.write();
+        let key_buffer: &mut [u8] = key_buffer.as_mut();
+
+        #[allow(
+            clippy::unwrap_used,
+            reason = "Better fail completely than return a weak key"
+        )]
+        hasher
+            .hash_password_into(password_source.deref(), salt, key_buffer)
+            .unwrap();
+    });
+
+    key.into()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::safe_cell::SafeCell;
+
+    #[test]
+    pub fn derive_seal_key_deterministic() {
+        static PASSWORD: &[u8] = b"password";
+        let password = SafeCell::new(PASSWORD.to_vec());
+        let password2 = SafeCell::new(PASSWORD.to_vec());
+        let salt = generate_salt();
+
+        let mut key1 = derive_seal_key(password, &salt);
+        let mut key2 = derive_seal_key(password2, &salt);
+
+        let key1_reader = key1.0.read();
+        let key2_reader = key2.0.read();
+
+        assert_eq!(key1_reader.deref(), key2_reader.deref());
+    }
+
+    #[test]
+    pub fn successful_derive() {
+        static PASSWORD: &[u8] = b"password";
+        let password = SafeCell::new(PASSWORD.to_vec());
+        let salt = generate_salt();
+
+        let mut key = derive_seal_key(password, &salt);
+        let key_reader = key.0.read();
+        let key_ref = key_reader.deref();
+
+        assert_ne!(key_ref.as_slice(), &[0u8; 32][..]);
+    }
+
+    #[test]
+    pub fn encrypt_decrypt() {
+        static PASSWORD: &[u8] = b"password";
+        let password = SafeCell::new(PASSWORD.to_vec());
+        let salt = generate_salt();
+
+        let mut key = derive_seal_key(password, &salt);
+        let nonce = Nonce(*b"unique nonce 123 1231233"); // 24 bytes for XChaCha20Poly1305
+        let associated_data = b"associated data";
+        let mut buffer = b"secret data".to_vec();
+
+        key.encrypt_in_place(&nonce, associated_data, &mut buffer)
+            .unwrap();
+        assert_ne!(buffer, b"secret data");
+
+        let mut buffer = SafeCell::new(buffer);
+
+        key.decrypt_in_place(&nonce, associated_data, &mut buffer)
+            .unwrap();
+
+        let buffer = buffer.read();
+        assert_eq!(*buffer, b"secret data");
+    }
+
+    #[test]
+    // We should fuzz this
+    pub fn test_nonce_increment() {
+        let mut nonce = Nonce([0u8; NONCE_LENGTH]);
+        nonce.increment();
+
+        assert_eq!(
+            nonce.0,
+            [
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
+            ]
+        );
+    }
+}

server/crates/arbiter-server/src/actors/keyholder/mod.rs

@@ -0,0 +1,412 @@
+use chrono::Utc;
+use diesel::{
+    ExpressionMethods as _, OptionalExtension, QueryDsl, SelectableHelper,
+    dsl::{insert_into, update},
+};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use kameo::{Actor, Reply, messages};
+use strum::{EnumDiscriminants, IntoDiscriminant};
+use tracing::{error, info};
+
+use crate::safe_cell::SafeCell;
+use crate::{
+    db::{
+        self,
+        models::{self, RootKeyHistory},
+        schema::{self},
+    },
+    safe_cell::SafeCellHandle as _,
+};
+use encryption::v1::{self, KeyCell, Nonce};
+
+pub mod encryption;
+
+#[derive(Default, EnumDiscriminants)]
+#[strum_discriminants(derive(Reply), vis(pub), name(KeyHolderState))]
+enum State {
+    #[default]
+    Unbootstrapped,
+    Sealed {
+        root_key_history_id: i32,
+    },
+    Unsealed {
+        root_key_history_id: i32,
+        root_key: KeyCell,
+    },
+}
+
+#[derive(Debug, thiserror::Error, miette::Diagnostic)]
+pub enum Error {
+    #[error("Keyholder is already bootstrapped")]
+    #[diagnostic(code(arbiter::keyholder::already_bootstrapped))]
+    AlreadyBootstrapped,
+    #[error("Keyholder is not bootstrapped")]
+    #[diagnostic(code(arbiter::keyholder::not_bootstrapped))]
+    NotBootstrapped,
+    #[error("Invalid key provided")]
+    #[diagnostic(code(arbiter::keyholder::invalid_key))]
+    InvalidKey,
+
+    #[error("Requested aead entry not found")]
+    #[diagnostic(code(arbiter::keyholder::aead_not_found))]
+    NotFound,
+
+    #[error("Encryption error: {0}")]
+    #[diagnostic(code(arbiter::keyholder::encryption_error))]
+    Encryption(#[from] chacha20poly1305::aead::Error),
+
+    #[error("Database error: {0}")]
+    #[diagnostic(code(arbiter::keyholder::database_error))]
+    DatabaseConnection(#[from] db::PoolError),
+
+    #[error("Database transaction error: {0}")]
+    #[diagnostic(code(arbiter::keyholder::database_transaction_error))]
+    DatabaseTransaction(#[from] diesel::result::Error),
+
+    #[error("Broken database")]
+    #[diagnostic(code(arbiter::keyholder::broken_database))]
+    BrokenDatabase,
+}
+
+/// Manages vault root key and tracks current state of the vault (bootstrapped/unbootstrapped, sealed/unsealed).
+/// Provides API for encrypting and decrypting data using the vault root key.
+/// Abstraction over database to make sure nonces are never reused and encryption keys are never exposed in plaintext outside of this actor.
+#[derive(Actor)]
+pub struct KeyHolder {
+    db: db::DatabasePool,
+    state: State,
+}
+
+#[messages]
+impl KeyHolder {
+    pub async fn new(db: db::DatabasePool) -> Result<Self, Error> {
+        let state = {
+            let mut conn = db.get().await?;
+
+            let (root_key_history,) = schema::arbiter_settings::table
+                .left_join(schema::root_key_history::table)
+                .select((Option::<RootKeyHistory>::as_select(),))
+                .get_result::<(Option<RootKeyHistory>,)>(&mut conn)
+                .await?;
+
+            match root_key_history {
+                Some(root_key_history) => State::Sealed {
+                    root_key_history_id: root_key_history.id,
+                },
+                None => State::Unbootstrapped,
+            }
+        };
+
+        Ok(Self { db, state })
+    }
+
+    // Exclusive transaction to avoid race condtions if multiple keyholders write
+    // additional layer of protection against nonce-reuse
+    async fn get_new_nonce(pool: &db::DatabasePool, root_key_id: i32) -> Result<Nonce, Error> {
+        let mut conn = pool.get().await?;
+
+        let nonce = conn
+            .exclusive_transaction(|conn| {
+                Box::pin(async move {
+                    let current_nonce: Vec<u8> = schema::root_key_history::table
+                        .filter(schema::root_key_history::id.eq(root_key_id))
+                        .select(schema::root_key_history::data_encryption_nonce)
+                        .first(conn)
+                        .await?;
+
+                    let mut nonce =
+                        v1::Nonce::try_from(current_nonce.as_slice()).map_err(|_| {
+                            error!(
+                                "Broken database: invalid nonce for root key history id={}",
+                                root_key_id
+                            );
+                            Error::BrokenDatabase
+                        })?;
+                    nonce.increment();
+
+                    update(schema::root_key_history::table)
+                        .filter(schema::root_key_history::id.eq(root_key_id))
+                        .set(schema::root_key_history::data_encryption_nonce.eq(nonce.to_vec()))
+                        .execute(conn)
+                        .await?;
+
+                    Result::<_, Error>::Ok(nonce)
+                })
+            })
+            .await?;
+
+        Ok(nonce)
+    }
+
+    #[message]
+    pub async fn bootstrap(&mut self, seal_key_raw: SafeCell<Vec<u8>>) -> Result<(), Error> {
+        if !matches!(self.state, State::Unbootstrapped) {
+            return Err(Error::AlreadyBootstrapped);
+        }
+        let salt = v1::generate_salt();
+        let mut seal_key = v1::derive_seal_key(seal_key_raw, &salt);
+        let mut root_key = KeyCell::new_secure_random();
+
+        // Zero nonces are fine because they are one-time
+        let root_key_nonce = v1::Nonce::default();
+        let data_encryption_nonce = v1::Nonce::default();
+
+        let root_key_ciphertext: Vec<u8> = root_key.0.read_inline(|reader| {
+            let root_key_reader = reader.as_slice();
+            seal_key
+                .encrypt(&root_key_nonce, v1::ROOT_KEY_TAG, root_key_reader)
+                .map_err(|err| {
+                    error!(?err, "Fatal bootstrap error");
+                    Error::Encryption(err)
+                })
+        })?;
+
+        let mut conn = self.db.get().await?;
+
+        let data_encryption_nonce_bytes = data_encryption_nonce.to_vec();
+        let root_key_history_id = conn
+            .transaction(|conn| {
+                Box::pin(async move {
+                    let root_key_history_id: i32 = insert_into(schema::root_key_history::table)
+                        .values(&models::NewRootKeyHistory {
+                            ciphertext: root_key_ciphertext,
+                            tag: v1::ROOT_KEY_TAG.to_vec(),
+                            root_key_encryption_nonce: root_key_nonce.to_vec(),
+                            data_encryption_nonce: data_encryption_nonce_bytes,
+                            schema_version: 1,
+                            salt: salt.to_vec(),
+                        })
+                        .returning(schema::root_key_history::id)
+                        .get_result(conn)
+                        .await?;
+
+                    update(schema::arbiter_settings::table)
+                        .set(schema::arbiter_settings::root_key_id.eq(root_key_history_id))
+                        .execute(conn)
+                        .await?;
+
+                    Result::<_, diesel::result::Error>::Ok(root_key_history_id)
+                })
+            })
+            .await?;
+
+        self.state = State::Unsealed {
+            root_key,
+            root_key_history_id,
+        };
+
+        info!("Keyholder bootstrapped successfully");
+
+        Ok(())
+    }
+
+    #[message]
+    pub async fn try_unseal(&mut self, seal_key_raw: SafeCell<Vec<u8>>) -> Result<(), Error> {
+        let State::Sealed {
+            root_key_history_id,
+        } = &self.state
+        else {
+            return Err(Error::NotBootstrapped);
+        };
+
+        // We don't want to hold connection while doing expensive KDF work
+        let current_key = {
+            let mut conn = self.db.get().await?;
+            schema::root_key_history::table
+                .filter(schema::root_key_history::id.eq(*root_key_history_id))
+                .select(schema::root_key_history::data_encryption_nonce)
+                .select(RootKeyHistory::as_select())
+                .first(&mut conn)
+                .await?
+        };
+
+        let salt = &current_key.salt;
+        let salt = v1::Salt::try_from(salt.as_slice()).map_err(|_| {
+            error!("Broken database: invalid salt for root key");
+            Error::BrokenDatabase
+        })?;
+        let mut seal_key = v1::derive_seal_key(seal_key_raw, &salt);
+
+        let mut root_key = SafeCell::new(current_key.ciphertext.clone());
+
+        let nonce = v1::Nonce::try_from(current_key.root_key_encryption_nonce.as_slice()).map_err(
+            |_| {
+                error!("Broken database: invalid nonce for root key");
+                Error::BrokenDatabase
+            },
+        )?;
+
+        seal_key
+            .decrypt_in_place(&nonce, v1::ROOT_KEY_TAG, &mut root_key)
+            .map_err(|err| {
+                error!(?err, "Failed to unseal root key: invalid seal key");
+                Error::InvalidKey
+            })?;
+
+        self.state = State::Unsealed {
+            root_key_history_id: current_key.id,
+            root_key: v1::KeyCell::try_from(root_key).map_err(|err| {
+                error!(?err, "Broken database: invalid encryption key size");
+                Error::BrokenDatabase
+            })?,
+        };
+
+        info!("Keyholder unsealed successfully");
+
+        Ok(())
+    }
+
+    // Decrypts the `aead_encrypted` entry with the given ID and returns the plaintext
+    #[message]
+    pub async fn decrypt(&mut self, aead_id: i32) -> Result<SafeCell<Vec<u8>>, Error> {
+        let State::Unsealed { root_key, .. } = &mut self.state else {
+            return Err(Error::NotBootstrapped);
+        };
+
+        let row: models::AeadEncrypted = {
+            let mut conn = self.db.get().await?;
+            schema::aead_encrypted::table
+                .select(models::AeadEncrypted::as_select())
+                .filter(schema::aead_encrypted::id.eq(aead_id))
+                .first(&mut conn)
+                .await
+                .optional()?
+                .ok_or(Error::NotFound)?
+        };
+
+        let nonce = v1::Nonce::try_from(row.current_nonce.as_slice()).map_err(|_| {
+            error!(
+                "Broken database: invalid nonce for aead_encrypted id={}",
+                aead_id
+            );
+            Error::BrokenDatabase
+        })?;
+        let mut output = SafeCell::new(row.ciphertext);
+        root_key.decrypt_in_place(&nonce, v1::TAG, &mut output)?;
+        Ok(output)
+    }
+
+    // Creates new `aead_encrypted` entry in the database and returns it's ID
+    #[message]
+    pub async fn create_new(&mut self, mut plaintext: SafeCell<Vec<u8>>) -> Result<i32, Error> {
+        let State::Unsealed {
+            root_key,
+            root_key_history_id,
+        } = &mut self.state
+        else {
+            return Err(Error::NotBootstrapped);
+        };
+
+        // Order matters here - `get_new_nonce` acquires connection, so we need to call it before next acquire
+        // Borrow checker note: &mut borrow a few lines above is disjoint from this field
+        let nonce = Self::get_new_nonce(&self.db, *root_key_history_id).await?;
+
+        let mut ciphertext_buffer = plaintext.write();
+        let ciphertext_buffer: &mut Vec<u8> = ciphertext_buffer.as_mut();
+        root_key.encrypt_in_place(&nonce, v1::TAG, &mut *ciphertext_buffer)?;
+
+        let ciphertext = std::mem::take(ciphertext_buffer);
+
+        let mut conn = self.db.get().await?;
+        let aead_id: i32 = insert_into(schema::aead_encrypted::table)
+            .values(&models::NewAeadEncrypted {
+                ciphertext,
+                tag: v1::TAG.to_vec(),
+                current_nonce: nonce.to_vec(),
+                schema_version: 1,
+                associated_root_key_id: *root_key_history_id,
+                created_at: Utc::now().into(),
+            })
+            .returning(schema::aead_encrypted::id)
+            .get_result(&mut conn)
+            .await?;
+
+        Ok(aead_id)
+    }
+
+    #[message]
+    pub fn get_state(&self) -> KeyHolderState {
+        self.state.discriminant()
+    }
+
+    #[message]
+    pub fn seal(&mut self) -> Result<(), Error> {
+        let State::Unsealed {
+            root_key_history_id,
+            ..
+        } = &self.state
+        else {
+            return Err(Error::NotBootstrapped);
+        };
+        self.state = State::Sealed {
+            root_key_history_id: *root_key_history_id,
+        };
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use diesel::SelectableHelper;
+
+    use diesel_async::RunQueryDsl;
+
+    use crate::{
+        db::{self},
+        safe_cell::SafeCell,
+    };
+
+    use super::*;
+
+    async fn bootstrapped_actor(db: &db::DatabasePool) -> KeyHolder {
+        let mut actor = KeyHolder::new(db.clone()).await.unwrap();
+        let seal_key = SafeCell::new(b"test-seal-key".to_vec());
+        actor.bootstrap(seal_key).await.unwrap();
+        actor
+    }
+
+    #[tokio::test]
+    #[test_log::test]
+    async fn nonce_monotonic_even_when_nonce_allocation_interleaves() {
+        let db = db::create_test_pool().await;
+        let mut actor = bootstrapped_actor(&db).await;
+        let root_key_history_id = match actor.state {
+            State::Unsealed {
+                root_key_history_id,
+                ..
+            } => root_key_history_id,
+            _ => panic!("expected unsealed state"),
+        };
+
+        let n1 = KeyHolder::get_new_nonce(&db, root_key_history_id)
+            .await
+            .unwrap();
+        let n2 = KeyHolder::get_new_nonce(&db, root_key_history_id)
+            .await
+            .unwrap();
+        assert!(n2.to_vec() > n1.to_vec(), "nonce must increase");
+
+        let mut conn = db.get().await.unwrap();
+        let root_row: models::RootKeyHistory = schema::root_key_history::table
+            .select(models::RootKeyHistory::as_select())
+            .first(&mut conn)
+            .await
+            .unwrap();
+        assert_eq!(root_row.data_encryption_nonce, n2.to_vec());
+
+        let id = actor
+            .create_new(SafeCell::new(b"post-interleave".to_vec()))
+            .await
+            .unwrap();
+        let row: models::AeadEncrypted = schema::aead_encrypted::table
+            .filter(schema::aead_encrypted::id.eq(id))
+            .select(models::AeadEncrypted::as_select())
+            .first(&mut conn)
+            .await
+            .unwrap();
+        assert!(
+            row.current_nonce > n2.to_vec(),
+            "next write must advance nonce"
+        );
+    }
+}

server/crates/arbiter-server/src/actors/mod.rs

@@ -1,123 +1,47 @@
+use kameo::actor::{ActorRef, Spawn};
+use miette::Diagnostic;
+use thiserror::Error;
+
 use crate::{
-    actors::{
-        bootstrap::Bootstrapper,
-        evm::EvmActor,
-        flow_coordinator::FlowCoordinator,
-        operator_registry::OperatorRegistry,
-        proposal_manager::{ProposalManager, events::ProposalApproved},
-        vault::{Vault, events},
-        vault_coordinator::VaultCoordinator,
-    },
+    actors::{bootstrap::Bootstrapper, evm::EvmActor, keyholder::KeyHolder, router::MessageRouter},
     db,
 };
 
-use kameo::actor::{ActorRef, Spawn};
-use kameo_actors::{
-    DeliveryStrategy,
-    message_bus::{MessageBus, Register},
-};
-use thiserror::Error;
-use tracing::error;
-
 pub mod bootstrap;
-pub mod evm;
-pub mod flow_coordinator;
-pub mod operator_registry;
-pub mod proposal_manager;
-pub mod vault;
-pub mod vault_coordinator;
+pub mod client;
+mod evm;
+pub mod keyholder;
+pub mod router;
+pub mod user_agent;
 
-#[derive(Error, Debug)]
+#[derive(Error, Debug, Diagnostic)]
 pub enum SpawnError {
     #[error("Failed to spawn Bootstrapper actor")]
+    #[diagnostic(code(SpawnError::Bootstrapper))]
     Bootstrapper(#[from] bootstrap::Error),
 
-    #[error("Failed to spawn Vault actor")]
-    Vault(#[from] vault::Error),
+    #[error("Failed to spawn KeyHolder actor")]
+    #[diagnostic(code(SpawnError::KeyHolder))]
+    KeyHolder(#[from] keyholder::Error),
 }
 
 /// Long-lived actors that are shared across all connections and handle global state and operations
 #[derive(Clone)]
 pub struct GlobalActors {
-    pub vault: ActorRef<Vault>,
+    pub key_holder: ActorRef<KeyHolder>,
     pub bootstrapper: ActorRef<Bootstrapper>,
-    pub vault_coordinator: ActorRef<VaultCoordinator>,
-    pub flow_coordinator: ActorRef<FlowCoordinator>,
-    pub operator_registry: ActorRef<OperatorRegistry>,
+    pub router: ActorRef<MessageRouter>,
     pub evm: ActorRef<EvmActor>,
-    pub proposal_manager: ActorRef<ProposalManager>,
-    pub events: ActorRef<MessageBus>,
 }
 
 impl GlobalActors {
-    pub fn spawn_message_bus() -> ActorRef<MessageBus> {
-        MessageBus::spawn(MessageBus::new(DeliveryStrategy::Guaranteed))
-    }
-
     pub async fn spawn(db: db::DatabasePool) -> Result<Self, SpawnError> {
-        let bootstrapper = Bootstrapper::new(&db).await?;
-        Self::spawn_with_bootstrapper(db, bootstrapper).await
-    }
-
-    /// Test-facing: threads an explicit directory through to `Bootstrapper` instead of letting
-    /// it resolve the real home directory, so a test spawning a full `GlobalActors` can never
-    /// reach (let alone write to) the real `~/.arbiter/bootstrap_token`. Mirrors `spawn`
-    /// exactly, aside from where the token file lives.
-    pub async fn spawn_in(
-        db: db::DatabasePool,
-        home: &std::path::Path,
-    ) -> Result<Self, SpawnError> {
-        let bootstrapper = Bootstrapper::new_in(&db, home).await?;
-        Self::spawn_with_bootstrapper(db, bootstrapper).await
-    }
-
-    async fn spawn_with_bootstrapper(
-        db: db::DatabasePool,
-        bootstrapper: Bootstrapper,
-    ) -> Result<Self, SpawnError> {
-        let message_bus = Self::spawn_message_bus();
-        let key_holder = Vault::spawn(Vault::new(db.clone(), message_bus.clone()).await?);
-        let operator_registry = OperatorRegistry::spawn(OperatorRegistry::default());
-        let evm = EvmActor::spawn(EvmActor::new(key_holder.clone(), db.clone()));
-        let vault_coordinator = VaultCoordinator::spawn(VaultCoordinator::new(
-            db.clone(),
-            key_holder.clone(),
-        ));
-        let bootstrapper = Bootstrapper::spawn(bootstrapper);
-        // Approved proposals are executed by whoever owns the kind, not by ProposalManager.
-        for recipient in [
-            evm.clone().recipient::<ProposalApproved>(),
-            vault_coordinator.clone().recipient::<ProposalApproved>(),
-            key_holder.clone().recipient::<ProposalApproved>(),
-        ] {
-            let _ = message_bus.tell(Register(recipient)).await;
-        }
-        // The token guards bootstrap only: once the vault reports success, it must be retired.
-        // A dropped registration would leave the token valid forever with nothing else to
-        // notice, so a failure here is logged rather than silently discarded.
-        if let Err(err) = message_bus
-            .tell(Register(
-                bootstrapper.clone().recipient::<events::Bootstrapped>(),
-            ))
-            .await
-        {
-            error!(
-                ?err,
-                "Failed to register Bootstrapper for the Bootstrapped event"
-            );
-        }
-
+        let key_holder = KeyHolder::spawn(KeyHolder::new(db.clone()).await?);
         Ok(Self {
-            bootstrapper,
-            proposal_manager: ProposalManager::spawn(ProposalManager::new(db, message_bus.clone())),
-            vault: key_holder,
-            vault_coordinator,
-            flow_coordinator: FlowCoordinator::spawn(FlowCoordinator::new(
-                operator_registry.clone(),
-            )),
-            operator_registry,
-            events: message_bus,
-            evm,
+            bootstrapper: Bootstrapper::spawn(Bootstrapper::new(&db).await?),
+            evm: EvmActor::spawn(EvmActor::new(key_holder.clone(), db)),
+            key_holder,
+            router: MessageRouter::spawn(MessageRouter::default()),
         })
     }
 }

server/crates/arbiter-server/src/actors/operator_registry.rs

@@ -1,61 +0,0 @@
-use crate::peers::operator::OperatorSession;
-
-use kameo::{
-    Actor,
-    actor::{ActorId, ActorRef},
-    error::Infallible,
-    messages,
-    prelude::{ActorStopReason, Context, WeakActorRef},
-};
-use std::{collections::HashMap, ops::ControlFlow};
-use tracing::info;
-
-#[derive(Default)]
-pub struct OperatorRegistry {
-    connected: HashMap<ActorId, ActorRef<OperatorSession>>,
-}
-
-impl Actor for OperatorRegistry {
-    type Args = Self;
-
-    type Error = Infallible;
-
-    async fn on_start(args: Self::Args, _: ActorRef<Self>) -> Result<Self, Self::Error> {
-        Ok(args)
-    }
-
-    async fn on_link_died(
-        &mut self,
-        _: WeakActorRef<Self>,
-        id: ActorId,
-        _: ActorStopReason,
-    ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
-        if self.connected.remove(&id).is_some() {
-            info!(
-                ?id,
-                actor = "OperatorRegistry",
-                event = "operator.disconnected"
-            );
-        }
-        Ok(ControlFlow::Continue(()))
-    }
-}
-
-#[messages]
-impl OperatorRegistry {
-    #[message(ctx)]
-    pub async fn connect_operator(
-        &mut self,
-        actor: ActorRef<OperatorSession>,
-        ctx: &mut Context<Self, ()>,
-    ) {
-        info!(id = %actor.id(), actor = "OperatorRegistry", event = "operator.connected");
-        ctx.actor_ref().link(&actor).await;
-        self.connected.insert(actor.id(), actor);
-    }
-
-    #[message]
-    pub fn get_connected(&self) -> Vec<ActorRef<OperatorSession>> {
-        self.connected.values().cloned().collect()
-    }
-}

server/crates/arbiter-server/src/actors/proposal_manager.rs

@@ -1,355 +0,0 @@
-use crate::{
-    actors::proposal_manager::{
-        events::ProposalApproved,
-        store::{DieselProposalStore, ProposalStore, Tally},
-    },
-    crypto::governance,
-    db::{
-        self,
-        models::{
-            NewProposalVote, NewRecoveryProposalVote, OperatorIdentityId, Proposal, ProposalId,
-            ProposalStatus, RecoveryOperatorIdentityId, SqliteTimestamp,
-        },
-        proposal::{ProposalKind, ProposalKindTag},
-    },
-};
-use chrono::Utc;
-use kameo::{Actor, actor::ActorRef, messages};
-use kameo_actors::message_bus::{MessageBus, Publish};
-use std::sync::Arc;
-use tracing::warn;
-
-pub mod events;
-pub mod store;
-
-pub const DEFAULT_TTL_SECS: u32 = 7 * 24 * 60 * 60; // 7 days
-pub const MAX_TTL_SECS: u32 = DEFAULT_TTL_SECS;
-
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub enum VoteOutcome {
-    Pending,
-    Approved,
-    Rejected,
-}
-
-#[derive(Debug, thiserror::Error)]
-pub enum Error {
-    #[error("Proposal not found")]
-    ProposalNotFound,
-    #[error("Proposal is not pending")]
-    ProposalNotPending,
-    #[error("Proposal has expired")]
-    ProposalExpired,
-    #[error("Requested TTL exceeds the maximum of {} seconds", MAX_TTL_SECS)]
-    TtlTooLong,
-    #[error("Operator already voted on this proposal")]
-    AlreadyVoted,
-    #[error("Invalid vote signature")]
-    InvalidSignature,
-    #[error("Operator not found")]
-    OperatorNotFound,
-    #[error("Database connection error: {0}")]
-    DatabaseConnection(#[from] db::PoolError),
-    #[error("Database query error: {0}")]
-    DatabaseQuery(#[from] diesel::result::Error),
-    #[error("Proposal manager is unavailable")]
-    Unavailable,
-    #[error("Recovery operators are sleeping")]
-    RecoveryNotActive,
-    #[error("Recovery operators may only vote on operator replacement")]
-    NotAllowedForRecoveryOperator,
-    #[error("A recovery wake-up is already pending or active")]
-    WakeupAlreadyPending,
-    #[error("No active recovery wake-up to cancel")]
-    NoActiveWakeup,
-}
-
-#[derive(Debug)]
-pub struct ProposalSummary {
-    pub id: ProposalId,
-    pub kind: ProposalKindTag,
-    pub initiator_id: OperatorIdentityId,
-    pub expires_at: SqliteTimestamp,
-    pub approve_count: i64,
-    pub reject_count: i64,
-}
-
-#[derive(Actor)]
-pub struct ProposalManager {
-    pub(crate) store: Arc<dyn ProposalStore>,
-    pub(crate) events: ActorRef<MessageBus>,
-}
-
-impl ProposalManager {
-    pub fn new(db: db::DatabasePool, events: ActorRef<MessageBus>) -> Self {
-        Self::with_store(Arc::new(DieselProposalStore::new(db)), events)
-    }
-
-    /// Builds the actor over an arbitrary store, so tests can supply a mock.
-    pub(crate) const fn with_store(
-        store: Arc<dyn ProposalStore>,
-        events: ActorRef<MessageBus>,
-    ) -> Self {
-        Self { store, events }
-    }
-}
-
-#[messages]
-impl ProposalManager {
-    #[message]
-    pub async fn create_proposal(
-        &mut self,
-        kind: ProposalKind,
-        initiator_id: OperatorIdentityId,
-        ttl_secs: Option<u32>,
-    ) -> Result<ProposalId, Error> {
-        let ttl = ttl_secs.unwrap_or(DEFAULT_TTL_SECS);
-        if ttl > MAX_TTL_SECS {
-            return Err(Error::TtlTooLong);
-        }
-        let expires_at =
-            SqliteTimestamp::from(Utc::now() + chrono::Duration::seconds(i64::from(ttl)));
-
-        self.store.create(kind, initiator_id, expires_at).await
-    }
-
-    #[message]
-    pub async fn query_pending(&mut self, operator_id: OperatorIdentityId) -> Vec<ProposalSummary> {
-        self.store
-            .pending_for(operator_id)
-            .await
-            .unwrap_or_else(|e| {
-                warn!(?e, "query_pending failed");
-                vec![]
-            })
-    }
-
-    #[message]
-    pub async fn cast_vote(
-        &mut self,
-        proposal_id: ProposalId,
-        operator_id: OperatorIdentityId,
-        approve: bool,
-        signature: Vec<u8>,
-    ) -> Result<VoteOutcome, Error> {
-        let proposal = self.store.load(proposal_id).await?;
-
-        // Checked before the status check so AlreadyVoted takes priority.
-        if self.store.has_voted(proposal_id, operator_id).await? {
-            return Err(Error::AlreadyVoted);
-        }
-
-        Self::check_votable(&proposal)?;
-
-        let public_key = self.store.operator_public_key(operator_id).await?;
-        governance::verify_vote(&public_key, proposal_id, approve, &signature)
-            .map_err(|_| Error::InvalidSignature)?;
-
-        self.store
-            .record_vote(NewProposalVote {
-                proposal_id,
-                operator_id,
-                approve,
-                signature,
-            })
-            .await?;
-
-        let mut tally = self.store.tally(proposal_id).await?;
-        self.narrow_electorate(&proposal, &mut tally).await?;
-
-        self.settle(&proposal, &tally).await
-    }
-
-    /// §3.6: Any ordinary operator may request recovery wake-up.
-    /// Fails if a wake-up is already pending or active.
-    #[message]
-    pub async fn request_recovery_wakeup(
-        &mut self,
-        operator_id: OperatorIdentityId,
-    ) -> Result<(), Error> {
-        if self.store.has_uncancelled_wakeup().await? {
-            return Err(Error::WakeupAlreadyPending);
-        }
-        self.store.request_wakeup(operator_id).await
-    }
-
-    /// §3.6: Any ordinary operator may cancel a pending wake-up request.
-    /// Fails if there is no uncancelled request.
-    #[message]
-    pub async fn cancel_recovery_wakeup(
-        &mut self,
-        operator_id: OperatorIdentityId,
-    ) -> Result<(), Error> {
-        if self.store.cancel_wakeup(operator_id).await? {
-            Ok(())
-        } else {
-            Err(Error::NoActiveWakeup)
-        }
-    }
-
-    /// §3.5: Recovery operators may only vote on operator replacement proposals.
-    /// §3.6: Voting is gated behind recovery being active (14-day window elapsed).
-    #[message]
-    pub async fn cast_recovery_vote(
-        &mut self,
-        proposal_id: ProposalId,
-        recovery_operator_id: RecoveryOperatorIdentityId,
-        approve: bool,
-        signature: Vec<u8>,
-    ) -> Result<VoteOutcome, Error> {
-        let proposal = self.store.load(proposal_id).await?;
-
-        if proposal.kind != ProposalKindTag::ReplaceOperator {
-            return Err(Error::NotAllowedForRecoveryOperator);
-        }
-
-        if !self.store.is_recovery_active().await? {
-            return Err(Error::RecoveryNotActive);
-        }
-
-        if self
-            .store
-            .has_recovery_voted(proposal_id, recovery_operator_id)
-            .await?
-        {
-            return Err(Error::AlreadyVoted);
-        }
-
-        Self::check_votable(&proposal)?;
-
-        let public_key = self
-            .store
-            .recovery_operator_public_key(recovery_operator_id)
-            .await?;
-        governance::verify_vote(&public_key, proposal_id, approve, &signature)
-            .map_err(|_| Error::InvalidSignature)?;
-
-        self.store
-            .record_recovery_vote(NewRecoveryProposalVote {
-                proposal_id,
-                recovery_operator_id,
-                approve,
-                signature,
-            })
-            .await?;
-
-        let mut tally = self.store.tally(proposal_id).await?;
-        self.narrow_electorate(&proposal, &mut tally).await?;
-
-        self.settle(&proposal, &tally).await
-    }
-}
-
-impl ProposalManager {
-    /// A vote only counts while the proposal is still open.
-    fn check_votable(proposal: &Proposal) -> Result<(), Error> {
-        if proposal.status != ProposalStatus::Pending {
-            return Err(Error::ProposalNotPending);
-        }
-        if proposal.expires_at.0 <= Utc::now() {
-            return Err(Error::ProposalExpired);
-        }
-        Ok(())
-    }
-
-    /// §3.5/§3.6: recovery operators join the electorate only for the kinds they may vote on,
-    /// and only once the wake-up window has elapsed. Counting them anywhere else makes the
-    /// rejection threshold unreachable and, for full-quorum kinds, approval unreachable too.
-    ///
-    /// The votes go out with the voters. A wake-up can be cancelled after recovery operators
-    /// have already voted (`cancel_wakeup` cancels any uncancelled request, elapsed or not),
-    /// so a `ReplaceOperator` tally can hold recovery approvals at the moment the committee
-    /// stops being eligible. Keeping those while zeroing only the electorate size would let
-    /// them cover ordinary votes that were never cast.
-    async fn narrow_electorate(&self, proposal: &Proposal, tally: &mut Tally) -> Result<(), Error> {
-        if !proposal.kind.recovery_may_vote() || !self.store.is_recovery_active().await? {
-            tally.drop_recovery();
-        }
-        Ok(())
-    }
-
-    /// Pure quorum arithmetic — no I/O, so the rules can be tested directly (§3.3).
-    ///
-    /// A proposal is rejected once approval has become unreachable: even if every voter
-    /// who has not spoken yet approved, the threshold could not be met.
-    #[must_use]
-    pub(crate) const fn evaluate_quorum(tally: &Tally, requires_full_quorum: bool) -> VoteOutcome {
-        let total_eligible = tally.total_ordinary + tally.total_recovery;
-
-        // No electorate, nothing to settle. Guarded before the branch rather than inside it:
-        // the full-quorum arm would otherwise set `threshold` to 0 and read an empty tally as
-        // unanimous approval.
-        if total_eligible <= 0 {
-            return VoteOutcome::Pending;
-        }
-
-        #[expect(
-            clippy::cast_possible_truncation,
-            clippy::cast_sign_loss,
-            clippy::cast_possible_wrap,
-            clippy::as_conversions,
-            reason = "operator counts are always small positive integers"
-        )]
-        // §3.3: key-rotation proposals require every eligible voter to approve.
-        // §3.5: when recovery is active, recovery operators are eligible too.
-        let threshold: i64 = if requires_full_quorum {
-            total_eligible
-        } else {
-            match crate::crypto::shamir::shamir_threshold(tally.total_ordinary as usize) {
-                Some(threshold) => threshold as i64,
-                // No ordinary operators means no electorate: nothing can settle.
-                None => return VoteOutcome::Pending,
-            }
-        };
-
-        if tally.approve() >= threshold {
-            VoteOutcome::Approved
-        } else if tally.reject() > total_eligible - threshold {
-            VoteOutcome::Rejected
-        } else {
-            VoteOutcome::Pending
-        }
-    }
-
-    /// Applies the quorum rules to a fresh tally and records whatever they decide.
-    async fn settle(&self, proposal: &Proposal, tally: &Tally) -> Result<VoteOutcome, Error> {
-        let outcome = Self::evaluate_quorum(tally, proposal.kind.requires_full_quorum());
-
-        match outcome {
-            VoteOutcome::Approved => self.announce_approval(proposal).await?,
-            VoteOutcome::Rejected => {
-                self.store
-                    .set_status(proposal.id, ProposalStatus::Rejected)
-                    .await?;
-            }
-            VoteOutcome::Pending => {}
-        }
-
-        Ok(outcome)
-    }
-
-    /// Marks the proposal approved and hands the outcome to whoever owns that kind.
-    ///
-    /// The outcome is published, not executed: this actor coordinates voting and nothing
-    /// else. Executors subscribe on the bus, so a vote is answered once the quorum is
-    /// recorded rather than once the effect has landed.
-    async fn announce_approval(&self, proposal: &Proposal) -> Result<(), Error> {
-        self.store
-            .set_status(proposal.id, ProposalStatus::Approved)
-            .await?;
-
-        let kind = self.store.load_kind(proposal.id, proposal.kind).await?;
-        let _ = self
-            .events
-            .tell(Publish(ProposalApproved {
-                id: proposal.id,
-                kind,
-            }))
-            .await;
-
-        Ok(())
-    }
-}
-
-#[cfg(test)]
-mod tests;

server/crates/arbiter-server/src/actors/proposal_manager/events.rs

@@ -1,11 +0,0 @@
-use crate::db::{models::ProposalId, proposal::ProposalKind};
-
-/// Published once a proposal reaches its approval threshold.
-///
-/// Executors subscribe on the global `MessageBus` and act on the kinds they own;
-/// `ProposalManager` does not know who acts on an outcome, or whether anyone does.
-#[derive(Debug, Clone)]
-pub struct ProposalApproved {
-    pub id: ProposalId,
-    pub kind: ProposalKind,
-}

server/crates/arbiter-server/src/actors/proposal_manager/store.rs

@@ -1,431 +0,0 @@
-//! Database access for [`super::ProposalManager`], behind a trait.
-//!
-//! The actor holds a `dyn ProposalStore` rather than a connection pool, so the quorum
-//! rules can be exercised against a mock instead of a live SQLite file.
-
-use super::{Error, ProposalSummary};
-use crate::db::{
-    self,
-    models::{
-        NewProposal, NewProposalVote, NewRecoveryProposalVote, NewRecoveryWakeupRequest,
-        OperatorIdentityId, Proposal, ProposalId, ProposalStatus, RecoveryOperatorIdentityId,
-        SqliteTimestamp,
-    },
-    proposal::{ProposalKind, ProposalKindTag},
-    schema,
-};
-
-use async_trait::async_trait;
-use chrono::Utc;
-use diesel::{
-    ExpressionMethods as _, QueryDsl,
-    dsl::{exists, select},
-};
-use diesel_async::{AsyncConnection as _, RunQueryDsl};
-use std::collections::HashMap;
-use strum::IntoDiscriminant as _;
-
-/// Everything the quorum rules need to know about one proposal's votes.
-///
-/// Votes are kept per electorate rather than pre-summed: an electorate can stop counting
-/// between the vote and the tally (§3.6 -- recovery goes back to sleep the moment a wake-up
-/// is cancelled), and the votes it already cast have to leave with it. A single `approve`
-/// field would carry them past [`Tally::drop_recovery`] into a threshold computed for the
-/// ordinary committee alone.
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-pub struct Tally {
-    pub ordinary_approve: i64,
-    pub ordinary_reject: i64,
-    pub recovery_approve: i64,
-    pub recovery_reject: i64,
-    pub total_ordinary: i64,
-    pub total_recovery: i64,
-}
-
-impl Tally {
-    /// Approvals from every electorate that still counts.
-    pub const fn approve(&self) -> i64 {
-        self.ordinary_approve + self.recovery_approve
-    }
-
-    /// Rejections from every electorate that still counts.
-    pub const fn reject(&self) -> i64 {
-        self.ordinary_reject + self.recovery_reject
-    }
-
-    /// Takes the recovery committee out of the electorate, votes and all. The three numbers
-    /// go together: leaving the votes behind counts them against a threshold derived from an
-    /// electorate they are no longer part of.
-    pub const fn drop_recovery(&mut self) {
-        self.recovery_approve = 0;
-        self.recovery_reject = 0;
-        self.total_recovery = 0;
-    }
-}
-
-#[cfg_attr(test, mockall::automock)]
-#[async_trait]
-pub trait ProposalStore: Send + Sync + 'static {
-    /// Writes the proposal and its kind-specific rows in one transaction.
-    async fn create(
-        &self,
-        kind: ProposalKind,
-        initiator_id: OperatorIdentityId,
-        expires_at: SqliteTimestamp,
-    ) -> Result<ProposalId, Error>;
-
-    async fn load(&self, id: ProposalId) -> Result<Proposal, Error>;
-
-    async fn load_kind(&self, id: ProposalId, tag: ProposalKindTag) -> Result<ProposalKind, Error>;
-
-    async fn has_voted(
-        &self,
-        id: ProposalId,
-        operator_id: OperatorIdentityId,
-    ) -> Result<bool, Error>;
-
-    async fn has_recovery_voted(
-        &self,
-        id: ProposalId,
-        recovery_operator_id: RecoveryOperatorIdentityId,
-    ) -> Result<bool, Error>;
-
-    async fn operator_public_key(&self, id: OperatorIdentityId) -> Result<Vec<u8>, Error>;
-
-    async fn recovery_operator_public_key(
-        &self,
-        id: RecoveryOperatorIdentityId,
-    ) -> Result<Vec<u8>, Error>;
-
-    async fn record_vote(&self, vote: NewProposalVote) -> Result<(), Error>;
-
-    async fn record_recovery_vote(&self, vote: NewRecoveryProposalVote) -> Result<(), Error>;
-
-    /// Vote counts for one proposal, alongside the size of each electorate.
-    async fn tally(&self, id: ProposalId) -> Result<Tally, Error>;
-
-    async fn set_status(&self, id: ProposalId, status: ProposalStatus) -> Result<(), Error>;
-
-    /// Pending, unexpired proposals this operator has not voted on yet.
-    async fn pending_for(
-        &self,
-        operator_id: OperatorIdentityId,
-    ) -> Result<Vec<ProposalSummary>, Error>;
-
-    /// True once an uncancelled wake-up request has outlived the dispute window.
-    async fn is_recovery_active(&self) -> Result<bool, Error>;
-
-    /// True while any wake-up request stands, whether or not the window has elapsed.
-    async fn has_uncancelled_wakeup(&self) -> Result<bool, Error>;
-
-    async fn request_wakeup(&self, operator_id: OperatorIdentityId) -> Result<(), Error>;
-
-    /// Returns false when there was no uncancelled request to cancel.
-    async fn cancel_wakeup(&self, operator_id: OperatorIdentityId) -> Result<bool, Error>;
-}
-
-pub struct DieselProposalStore {
-    db: db::DatabasePool,
-}
-
-impl DieselProposalStore {
-    pub const fn new(db: db::DatabasePool) -> Self {
-        Self { db }
-    }
-}
-
-/// `NotFound` means the row is absent, which every caller reports as its own error.
-fn missing(absent: Error) -> impl FnOnce(diesel::result::Error) -> Error {
-    move |e| match e {
-        diesel::result::Error::NotFound => absent,
-        other => Error::DatabaseQuery(other),
-    }
-}
-
-#[async_trait]
-impl ProposalStore for DieselProposalStore {
-    async fn create(
-        &self,
-        kind: ProposalKind,
-        initiator_id: OperatorIdentityId,
-        expires_at: SqliteTimestamp,
-    ) -> Result<ProposalId, Error> {
-        let id = self
-            .db
-            .get()
-            .await?
-            .transaction(async |conn| {
-                let id: ProposalId = diesel::insert_into(schema::proposal::table)
-                    .values(&NewProposal {
-                        kind: kind.discriminant(),
-                        initiator_id,
-                        expires_at,
-                    })
-                    .returning(schema::proposal::id)
-                    .get_result(conn)
-                    .await?;
-                db::proposal::insert_kind(conn, id, &kind).await?;
-                Ok::<_, diesel::result::Error>(id)
-            })
-            .await?;
-
-        Ok(id)
-    }
-
-    async fn load(&self, id: ProposalId) -> Result<Proposal, Error> {
-        let mut conn = self.db.get().await?;
-        schema::proposal::table
-            .find(id)
-            .first(&mut conn)
-            .await
-            .map_err(missing(Error::ProposalNotFound))
-    }
-
-    async fn load_kind(&self, id: ProposalId, tag: ProposalKindTag) -> Result<ProposalKind, Error> {
-        let mut conn = self.db.get().await?;
-        db::proposal::load_kind(&mut conn, id, tag)
-            .await
-            .map_err(Error::from)
-    }
-
-    async fn has_voted(
-        &self,
-        id: ProposalId,
-        operator_id: OperatorIdentityId,
-    ) -> Result<bool, Error> {
-        let mut conn = self.db.get().await?;
-        select(exists(
-            schema::proposal_vote::table
-                .filter(schema::proposal_vote::proposal_id.eq(id))
-                .filter(schema::proposal_vote::operator_id.eq(operator_id)),
-        ))
-        .get_result(&mut conn)
-        .await
-        .map_err(Error::from)
-    }
-
-    async fn has_recovery_voted(
-        &self,
-        id: ProposalId,
-        recovery_operator_id: RecoveryOperatorIdentityId,
-    ) -> Result<bool, Error> {
-        let mut conn = self.db.get().await?;
-        select(exists(
-            schema::recovery_proposal_vote::table
-                .filter(schema::recovery_proposal_vote::proposal_id.eq(id))
-                .filter(
-                    schema::recovery_proposal_vote::recovery_operator_id.eq(recovery_operator_id),
-                ),
-        ))
-        .get_result(&mut conn)
-        .await
-        .map_err(Error::from)
-    }
-
-    async fn operator_public_key(&self, id: OperatorIdentityId) -> Result<Vec<u8>, Error> {
-        let mut conn = self.db.get().await?;
-        schema::operator_identity::table
-            .find(id)
-            .select(schema::operator_identity::public_key)
-            .first(&mut conn)
-            .await
-            .map_err(missing(Error::OperatorNotFound))
-    }
-
-    async fn recovery_operator_public_key(
-        &self,
-        id: RecoveryOperatorIdentityId,
-    ) -> Result<Vec<u8>, Error> {
-        let mut conn = self.db.get().await?;
-        schema::recovery_operator_identity::table
-            .find(id)
-            .select(schema::recovery_operator_identity::public_key)
-            .first(&mut conn)
-            .await
-            .map_err(missing(Error::OperatorNotFound))
-    }
-
-    async fn record_vote(&self, vote: NewProposalVote) -> Result<(), Error> {
-        let mut conn = self.db.get().await?;
-        diesel::insert_into(schema::proposal_vote::table)
-            .values(&vote)
-            .execute(&mut conn)
-            .await?;
-        Ok(())
-    }
-
-    async fn record_recovery_vote(&self, vote: NewRecoveryProposalVote) -> Result<(), Error> {
-        let mut conn = self.db.get().await?;
-        diesel::insert_into(schema::recovery_proposal_vote::table)
-            .values(&vote)
-            .execute(&mut conn)
-            .await?;
-        Ok(())
-    }
-
-    async fn tally(&self, id: ProposalId) -> Result<Tally, Error> {
-        let mut conn = self.db.get().await?;
-
-        let ordinary_approve: i64 = schema::proposal_vote::table
-            .filter(schema::proposal_vote::proposal_id.eq(id))
-            .filter(schema::proposal_vote::approve.eq(true))
-            .count()
-            .get_result(&mut conn)
-            .await?;
-        let recovery_approve: i64 = schema::recovery_proposal_vote::table
-            .filter(schema::recovery_proposal_vote::proposal_id.eq(id))
-            .filter(schema::recovery_proposal_vote::approve.eq(true))
-            .count()
-            .get_result(&mut conn)
-            .await?;
-
-        let ordinary_reject: i64 = schema::proposal_vote::table
-            .filter(schema::proposal_vote::proposal_id.eq(id))
-            .filter(schema::proposal_vote::approve.eq(false))
-            .count()
-            .get_result(&mut conn)
-            .await?;
-        let recovery_reject: i64 = schema::recovery_proposal_vote::table
-            .filter(schema::recovery_proposal_vote::proposal_id.eq(id))
-            .filter(schema::recovery_proposal_vote::approve.eq(false))
-            .count()
-            .get_result(&mut conn)
-            .await?;
-
-        let total_ordinary: i64 = schema::operator_identity::table
-            .count()
-            .get_result(&mut conn)
-            .await?;
-        let total_recovery: i64 = schema::recovery_operator_identity::table
-            .count()
-            .get_result(&mut conn)
-            .await?;
-
-        Ok(Tally {
-            ordinary_approve,
-            ordinary_reject,
-            recovery_approve,
-            recovery_reject,
-            total_ordinary,
-            total_recovery,
-        })
-    }
-
-    async fn set_status(&self, id: ProposalId, status: ProposalStatus) -> Result<(), Error> {
-        let mut conn = self.db.get().await?;
-        diesel::update(schema::proposal::table.find(id))
-            .set(schema::proposal::status.eq(status))
-            .execute(&mut conn)
-            .await?;
-        Ok(())
-    }
-
-    async fn pending_for(
-        &self,
-        operator_id: OperatorIdentityId,
-    ) -> Result<Vec<ProposalSummary>, Error> {
-        #[expect(
-            clippy::cast_possible_truncation,
-            clippy::as_conversions,
-            reason = "fixme! #84; this will break in 2038"
-        )]
-        let now_ts = Utc::now().timestamp() as i32;
-
-        let mut conn = self.db.get().await?;
-
-        let voted_ids: Vec<ProposalId> = schema::proposal_vote::table
-            .filter(schema::proposal_vote::operator_id.eq(operator_id))
-            .select(schema::proposal_vote::proposal_id)
-            .load(&mut conn)
-            .await?;
-
-        let proposals: Vec<Proposal> = schema::proposal::table
-            .filter(schema::proposal::status.eq(ProposalStatus::Pending))
-            .filter(schema::proposal::expires_at.gt(now_ts))
-            .filter(diesel::dsl::not(schema::proposal::id.eq_any(&voted_ids)))
-            .load(&mut conn)
-            .await?;
-
-        let ids: Vec<ProposalId> = proposals.iter().map(|p| p.id).collect();
-        let tallies: Vec<(ProposalId, bool, i64)> = schema::proposal_vote::table
-            .filter(schema::proposal_vote::proposal_id.eq_any(&ids))
-            .group_by((
-                schema::proposal_vote::proposal_id,
-                schema::proposal_vote::approve,
-            ))
-            .select((
-                schema::proposal_vote::proposal_id,
-                schema::proposal_vote::approve,
-                diesel::dsl::count_star(),
-            ))
-            .load(&mut conn)
-            .await?;
-
-        let mut by_proposal: HashMap<ProposalId, (i64, i64)> = HashMap::new();
-        for (proposal_id, approve, count) in tallies {
-            let entry = by_proposal.entry(proposal_id).or_insert((0, 0));
-            if approve {
-                entry.0 += count;
-            } else {
-                entry.1 += count;
-            }
-        }
-
-        Ok(proposals
-            .into_iter()
-            .map(|p| {
-                let (approve_count, reject_count) =
-                    by_proposal.get(&p.id).copied().unwrap_or((0, 0));
-                ProposalSummary {
-                    id: p.id,
-                    kind: p.kind,
-                    initiator_id: p.initiator_id,
-                    expires_at: p.expires_at,
-                    approve_count,
-                    reject_count,
-                }
-            })
-            .collect())
-    }
-
-    async fn is_recovery_active(&self) -> Result<bool, Error> {
-        let mut conn = self.db.get().await?;
-        db::recovery::is_active(&mut conn)
-            .await
-            .map_err(Error::from)
-    }
-
-    async fn has_uncancelled_wakeup(&self) -> Result<bool, Error> {
-        let mut conn = self.db.get().await?;
-        select(exists(schema::recovery_wakeup_request::table.filter(
-            schema::recovery_wakeup_request::cancelled_at.is_null(),
-        )))
-        .get_result(&mut conn)
-        .await
-        .map_err(Error::from)
-    }
-
-    async fn request_wakeup(&self, operator_id: OperatorIdentityId) -> Result<(), Error> {
-        let mut conn = self.db.get().await?;
-        diesel::insert_into(schema::recovery_wakeup_request::table)
-            .values(&NewRecoveryWakeupRequest {
-                requested_by: operator_id,
-            })
-            .execute(&mut conn)
-            .await?;
-        Ok(())
-    }
-
-    async fn cancel_wakeup(&self, operator_id: OperatorIdentityId) -> Result<bool, Error> {
-        let mut conn = self.db.get().await?;
-        let rows = diesel::update(schema::recovery_wakeup_request::table)
-            .filter(schema::recovery_wakeup_request::cancelled_at.is_null())
-            .set((
-                schema::recovery_wakeup_request::cancelled_by.eq(Some(operator_id)),
-                schema::recovery_wakeup_request::cancelled_at.eq(Some(SqliteTimestamp::now())),
-            ))
-            .execute(&mut conn)
-            .await?;
-        Ok(rows > 0)
-    }
-}

server/crates/arbiter-server/src/actors/proposal_manager/tests.rs

@@ -1,395 +0,0 @@
-//! The quorum rules, exercised without a database.
-//!
-//! These assertions are the point of [`super::store::ProposalStore`]: until the actor took
-//! its data through a trait, checking that two of three operators carry an ordinary
-//! proposal meant opening SQLite and registering operators first.
-
-use super::{
-    ProposalManager, VoteOutcome,
-    store::{MockProposalStore, Tally},
-};
-use crate::{
-    actors::GlobalActors,
-    crypto::governance::vote_message,
-    db::{
-        models::{OperatorIdentityId, Proposal, ProposalId, ProposalStatus, SqliteTimestamp},
-        proposal::ProposalKindTag,
-    },
-};
-use arbiter_crypto::authn::{SigningContext, SigningKey};
-use chrono::{Duration, Utc};
-use std::sync::Arc;
-
-/// A tally where every vote came from the ordinary committee.
-const fn tally(approve: i64, reject: i64, ordinary: i64, recovery: i64) -> Tally {
-    Tally {
-        ordinary_approve: approve,
-        ordinary_reject: reject,
-        recovery_approve: 0,
-        recovery_reject: 0,
-        total_ordinary: ordinary,
-        total_recovery: recovery,
-    }
-}
-
-/// A tally with votes from both committees, in the order approve/reject per committee.
-const fn mixed_tally(
-    ordinary_approve: i64,
-    ordinary_reject: i64,
-    recovery_approve: i64,
-    recovery_reject: i64,
-    total_ordinary: i64,
-    total_recovery: i64,
-) -> Tally {
-    Tally {
-        ordinary_approve,
-        ordinary_reject,
-        recovery_approve,
-        recovery_reject,
-        total_ordinary,
-        total_recovery,
-    }
-}
-
-#[test]
-fn simple_majority_approves_at_two_of_three() {
-    assert_eq!(
-        ProposalManager::evaluate_quorum(&tally(2, 0, 3, 0), false),
-        VoteOutcome::Approved
-    );
-}
-
-#[test]
-fn one_of_three_is_not_yet_a_majority() {
-    assert_eq!(
-        ProposalManager::evaluate_quorum(&tally(1, 0, 3, 0), false),
-        VoteOutcome::Pending
-    );
-}
-
-#[test]
-fn full_quorum_kind_needs_every_voter() {
-    assert_eq!(
-        ProposalManager::evaluate_quorum(&tally(2, 0, 3, 0), true),
-        VoteOutcome::Pending,
-        "two of three must not carry a key-rotation proposal"
-    );
-}
-
-#[test]
-fn recovery_voters_count_towards_full_quorum() {
-    assert_eq!(
-        ProposalManager::evaluate_quorum(&mixed_tally(2, 0, 1, 0, 2, 1), true),
-        VoteOutcome::Approved
-    );
-    assert_eq!(
-        ProposalManager::evaluate_quorum(&mixed_tally(2, 0, 0, 0, 2, 1), true),
-        VoteOutcome::Pending,
-        "the sleeping recovery operator still owes a vote"
-    );
-}
-
-/// An empty committee cannot approve anything. Both arms have to say so: the full-quorum arm
-/// derives its threshold from the electorate, so with nobody eligible it would compare 0
-/// approvals against a threshold of 0 and call that unanimous.
-#[test]
-fn an_empty_electorate_settles_nothing() {
-    assert_eq!(
-        ProposalManager::evaluate_quorum(&tally(0, 0, 0, 0), true),
-        VoteOutcome::Pending,
-        "a full-quorum proposal must not pass with no eligible voters"
-    );
-    assert_eq!(
-        ProposalManager::evaluate_quorum(&tally(0, 0, 0, 0), false),
-        VoteOutcome::Pending
-    );
-}
-
-#[test]
-fn rejection_is_decided_once_approval_is_unreachable() {
-    // Threshold is 2 of 3, so two rejections leave at most one approval available.
-    assert_eq!(
-        ProposalManager::evaluate_quorum(&tally(0, 2, 3, 0), false),
-        VoteOutcome::Rejected
-    );
-    assert_eq!(
-        ProposalManager::evaluate_quorum(&tally(0, 1, 3, 0), false),
-        VoteOutcome::Pending,
-        "one rejection still leaves two approvals reachable"
-    );
-}
-
-#[test]
-fn a_single_rejection_sinks_a_full_quorum_proposal() {
-    assert_eq!(
-        ProposalManager::evaluate_quorum(&tally(2, 1, 3, 0), true),
-        VoteOutcome::Rejected
-    );
-}
-
-fn pending_proposal(id: ProposalId, kind: ProposalKindTag) -> Proposal {
-    let now = Utc::now();
-    Proposal {
-        id,
-        kind,
-        initiator_id: OperatorIdentityId::from_raw(1),
-        created_at: SqliteTimestamp::from(now),
-        expires_at: SqliteTimestamp::from(now + Duration::days(1)),
-        status: ProposalStatus::Pending,
-    }
-}
-
-/// The mock earns its keep here: reaching quorum must flip the stored status to
-/// `Approved` exactly once. Signature verification stays real -- only the database is
-/// stubbed out.
-#[tokio::test]
-async fn reaching_quorum_marks_the_proposal_approved() {
-    let id = ProposalId::from_raw(1);
-    let voter = OperatorIdentityId::from_raw(1);
-    let key = SigningKey::generate();
-    let signature = key
-        .sign_message(&vote_message(id, true), SigningContext::GovernanceVote)
-        .expect("signing a vote must succeed");
-    let public_key = key.public_key().to_bytes();
-
-    let mut store = MockProposalStore::new();
-    store
-        .expect_load()
-        .returning(move |id| Ok(pending_proposal(id, ProposalKindTag::TriggerRekey)));
-    store.expect_has_voted().returning(|_, _| Ok(false));
-    store
-        .expect_operator_public_key()
-        .returning(move |_| Ok(public_key.clone()));
-    store.expect_record_vote().returning(|_| Ok(()));
-    store.expect_is_recovery_active().returning(|| Ok(false));
-    store.expect_tally().returning(|_| Ok(tally(1, 0, 1, 0)));
-    store
-        .expect_set_status()
-        .withf(move |got, status| *got == id && *status == ProposalStatus::Approved)
-        .times(1)
-        .returning(|_, _| Ok(()));
-    store
-        .expect_load_kind()
-        .returning(|_, _| Ok(crate::db::proposal::ProposalKind::TriggerRekey));
-
-    let mut manager =
-        ProposalManager::with_store(Arc::new(store), GlobalActors::spawn_message_bus());
-
-    let outcome = manager
-        .cast_vote(id, voter, true, signature.to_bytes())
-        .await
-        .expect("a valid vote must be accepted");
-
-    assert_eq!(outcome, VoteOutcome::Approved);
-}
-
-/// A vote that does not reach the threshold must leave the stored status alone.
-#[tokio::test]
-async fn a_vote_short_of_quorum_does_not_touch_the_status() {
-    let id = ProposalId::from_raw(7);
-    let voter = OperatorIdentityId::from_raw(2);
-    let key = SigningKey::generate();
-    let signature = key
-        .sign_message(&vote_message(id, true), SigningContext::GovernanceVote)
-        .expect("signing a vote must succeed");
-    let public_key = key.public_key().to_bytes();
-
-    let mut store = MockProposalStore::new();
-    store
-        .expect_load()
-        .returning(move |id| Ok(pending_proposal(id, ProposalKindTag::ApproveSdkClient)));
-    store.expect_has_voted().returning(|_, _| Ok(false));
-    store
-        .expect_operator_public_key()
-        .returning(move |_| Ok(public_key.clone()));
-    store.expect_record_vote().returning(|_| Ok(()));
-    store.expect_is_recovery_active().returning(|| Ok(false));
-    store.expect_tally().returning(|_| Ok(tally(1, 0, 3, 0)));
-    store.expect_set_status().never();
-
-    let mut manager =
-        ProposalManager::with_store(Arc::new(store), GlobalActors::spawn_message_bus());
-
-    let outcome = manager
-        .cast_vote(id, voter, true, signature.to_bytes())
-        .await
-        .expect("a valid vote must be accepted");
-
-    assert_eq!(outcome, VoteOutcome::Pending);
-}
-
-/// Drives one `cast_vote` on a proposal of the given `kind` through a mocked store and
-/// returns the outcome. `recovery_active` decides what `is_recovery_active` reports;
-/// `expected_status` is the status a settled outcome must be persisted under, or `None` for
-/// a caller that expects the vote to leave the proposal pending.
-///
-/// `set_status` carries an argument matcher but no `.times()`, and `None` relaxes even the
-/// matcher: the caller's own `assert_eq!` on the outcome is what pins the behaviour, so a
-/// regression fails on a readable diff rather than on a mockall cardinality panic that hides
-/// what the actor actually computed.
-async fn settle_vote_with(
-    kind: ProposalKindTag,
-    tally: Tally,
-    recovery_active: bool,
-    expected_status: Option<ProposalStatus>,
-) -> VoteOutcome {
-    let id = ProposalId::from_raw(11);
-    let voter = OperatorIdentityId::from_raw(1);
-    let key = SigningKey::generate();
-    let signature = key
-        .sign_message(&vote_message(id, true), SigningContext::GovernanceVote)
-        .expect("signing a vote must succeed");
-    let public_key = key.public_key().to_bytes();
-
-    let mut store = MockProposalStore::new();
-    store
-        .expect_load()
-        .returning(move |id| Ok(pending_proposal(id, kind)));
-    store.expect_has_voted().returning(|_, _| Ok(false));
-    store
-        .expect_operator_public_key()
-        .returning(move |_| Ok(public_key.clone()));
-    store.expect_record_vote().returning(|_| Ok(()));
-    store
-        .expect_is_recovery_active()
-        .returning(move || Ok(recovery_active));
-    store.expect_tally().returning(move |_| Ok(tally));
-    store
-        .expect_set_status()
-        .withf(move |_, status| {
-            expected_status
-                .as_ref()
-                .is_none_or(|expected| status == expected)
-        })
-        .returning(|_, _| Ok(()));
-    store.expect_load_kind().returning(move |_, _| {
-        Ok(match kind {
-            ProposalKindTag::TriggerRekey => crate::db::proposal::ProposalKind::TriggerRekey,
-            ProposalKindTag::ApproveSdkClient => {
-                crate::db::proposal::ProposalKind::ApproveSdkClient(
-                    crate::db::proposal::approve_sdk_client::Settings { client_id: 1 },
-                )
-            }
-            ProposalKindTag::ReplaceOperator => crate::db::proposal::ProposalKind::ReplaceOperator(
-                crate::db::proposal::replace_operator::Settings {
-                    old_operator_id: OperatorIdentityId::from_raw(1),
-                    new_pubkey: vec![0u8; 32],
-                },
-            ),
-            other => unreachable!("settle_vote_with has no load_kind fixture for {other:?}"),
-        })
-    });
-
-    let mut manager =
-        ProposalManager::with_store(Arc::new(store), GlobalActors::spawn_message_bus());
-
-    manager
-        .cast_vote(id, voter, true, signature.to_bytes())
-        .await
-        .expect("a valid vote must be accepted")
-}
-
-/// The full-quorum rejection path is insensitive to electorate size by construction:
-/// `threshold == total_eligible` there, so `total_eligible - threshold` is always 0 and any
-/// single rejection settles the proposal, whether or not recovery operators are (wrongly)
-/// counted. This does not exercise the electorate-narrowing fix -- see
-/// `unanimous_ordinary_rejection_rejects_a_non_full_quorum_proposal_while_recovery_is_awake`
-/// below for the test that does -- it just pins that `cast_vote` still writes `Rejected`
-/// through `settle` for a full-quorum kind.
-#[tokio::test]
-async fn unanimous_rejection_settles_a_full_quorum_rekey_via_cast_vote() {
-    let outcome = settle_vote_with(
-        ProposalKindTag::TriggerRekey,
-        tally(0, 3, 3, 2),
-        /* recovery_active */ true,
-        Some(ProposalStatus::Rejected),
-    )
-    .await;
-
-    assert_eq!(outcome, VoteOutcome::Rejected);
-}
-
-/// §3.3 full quorum for a rekey means every *ordinary* operator, not every identity on file.
-#[tokio::test]
-async fn unanimous_ordinary_approval_approves_a_rekey_while_recovery_is_awake() {
-    let outcome = settle_vote_with(
-        ProposalKindTag::TriggerRekey,
-        tally(3, 0, 3, 2),
-        /* recovery_active */ true,
-        Some(ProposalStatus::Approved),
-    )
-    .await;
-
-    assert_eq!(outcome, VoteOutcome::Approved);
-}
-
-/// §3.5: recovery operators do not vote on `ApproveSdkClient`, so they must not inflate its
-/// electorate. Before the fix, `total_eligible` counted them anyway (5, not 3), so the
-/// rejection test `reject > total_eligible - threshold` became `3 > 5 - 2 = 3`, which is
-/// false -- three unanimous rejections left the proposal `Pending` forever, since a fourth
-/// vote could never arrive. After the fix, `total_eligible` is 3 and the same test becomes
-/// `3 > 3 - 2 = 1`, which settles it.
-#[tokio::test]
-async fn unanimous_ordinary_rejection_rejects_a_non_full_quorum_proposal_while_recovery_is_awake() {
-    let outcome = settle_vote_with(
-        ProposalKindTag::ApproveSdkClient,
-        tally(0, 3, 3, 2),
-        /* recovery_active */ true,
-        Some(ProposalStatus::Rejected),
-    )
-    .await;
-
-    assert_eq!(outcome, VoteOutcome::Rejected);
-}
-
-/// §3.5/§3.6: `ReplaceOperator` is the one kind recovery may vote on, so it is the only kind
-/// where whether recovery is awake is observable at all -- for every other kind
-/// `narrow_electorate` zeroes `total_recovery` regardless of `is_recovery_active`, short-
-/// circuiting before that call. A sleeping recovery electorate must not raise the bar here:
-/// with 1 ordinary operator and 2 (asleep) recovery operators, the lone ordinary approval
-/// must already reach full quorum.
-#[tokio::test]
-async fn sleeping_recovery_operators_do_not_count_towards_quorum() {
-    let outcome = settle_vote_with(
-        ProposalKindTag::ReplaceOperator,
-        tally(1, 0, 1, 2),
-        /* recovery_active */ false,
-        Some(ProposalStatus::Approved),
-    )
-    .await;
-
-    assert_eq!(outcome, VoteOutcome::Approved);
-}
-
-/// The sequence the whole-branch review worked through, on a `ReplaceOperator` with 3
-/// ordinary and 2 recovery operators (§3.3: full quorum). Both recovery operators approve
-/// while awake; one ordinary operator approves; another ordinary operator then cancels the
-/// wake-up -- `cancel_wakeup` cancels an uncancelled request whether or not its window has
-/// elapsed, so the committee goes straight back to sleep with its votes on the record; a
-/// second ordinary operator approves.
-///
-/// The store now reports 4 approvals, 2 of them from a committee that is no longer eligible.
-/// Narrowing the electorate has to drop those votes along with the voters: what is left is 2
-/// of 3 ordinary approvals, and a full quorum needs all three. Counting the electorate down
-/// to 3 while keeping all 4 votes would replace an operator on two ordinary approvals.
-#[tokio::test]
-async fn recovery_votes_leave_with_the_committee_that_cast_them() {
-    let outcome = settle_vote_with(
-        ProposalKindTag::ReplaceOperator,
-        mixed_tally(
-            /* ordinary_approve */ 2, /* ordinary_reject */ 0,
-            /* recovery_approve */ 2, /* recovery_reject */ 0,
-            /* total_ordinary */ 3, /* total_recovery */ 2,
-        ),
-        /* recovery_active */ false,
-        None,
-    )
-    .await;
-
-    assert_eq!(
-        outcome,
-        VoteOutcome::Pending,
-        "two of three ordinary approvals must not carry a full-quorum proposal, whatever a \
-         sleeping recovery committee voted earlier"
-    );
-}

server/crates/arbiter-server/src/actors/router/mod.rs

@@ -0,0 +1,173 @@
+use std::{collections::HashMap, ops::ControlFlow};
+
+use ed25519_dalek::VerifyingKey;
+use kameo::{
+    Actor,
+    actor::{ActorId, ActorRef},
+    messages,
+    prelude::{ActorStopReason, Context, WeakActorRef},
+    reply::DelegatedReply,
+};
+use tokio::{sync::watch, task::JoinSet};
+use tracing::{info, warn};
+
+use crate::actors::{
+    client::session::ClientSession,
+    user_agent::session::{RequestNewClientApproval, UserAgentSession},
+};
+
+#[derive(Default)]
+pub struct MessageRouter {
+    pub user_agents: HashMap<ActorId, ActorRef<UserAgentSession>>,
+    pub clients: HashMap<ActorId, ActorRef<ClientSession>>,
+}
+
+impl Actor for MessageRouter {
+    type Args = Self;
+
+    type Error = ();
+
+    async fn on_start(args: Self::Args, _: ActorRef<Self>) -> Result<Self, Self::Error> {
+        Ok(args)
+    }
+
+    async fn on_link_died(
+        &mut self,
+        _: WeakActorRef<Self>,
+        id: ActorId,
+        _: ActorStopReason,
+    ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
+        if self.user_agents.remove(&id).is_some() {
+            info!(
+                ?id,
+                actor = "MessageRouter",
+                event = "useragent.disconnected"
+            );
+        } else if self.clients.remove(&id).is_some() {
+            info!(?id, actor = "MessageRouter", event = "client.disconnected");
+        } else {
+            info!(
+                ?id,
+                actor = "MessageRouter",
+                event = "unknown.actor.disconnected"
+            );
+        }
+        Ok(ControlFlow::Continue(()))
+    }
+}
+
+#[derive(Debug, thiserror::Error, Clone, PartialEq, Eq, Hash)]
+pub enum ApprovalError {
+    #[error("No user agents connected")]
+    NoUserAgentsConnected,
+}
+
+async fn request_client_approval(
+    user_agents: &[WeakActorRef<UserAgentSession>],
+    client_pubkey: VerifyingKey,
+) -> Result<bool, ApprovalError> {
+    if user_agents.is_empty() {
+        return Err(ApprovalError::NoUserAgentsConnected);
+    }
+
+    let mut pool = JoinSet::new();
+    let (cancel_tx, cancel_rx) = watch::channel(());
+
+    for weak_ref in user_agents {
+        match weak_ref.upgrade() {
+            Some(agent) => {
+                let cancel_rx = cancel_rx.clone();
+                pool.spawn(async move {
+                    agent
+                        .ask(RequestNewClientApproval {
+                            client_pubkey,
+                            cancel_flag: cancel_rx.clone(),
+                        })
+                        .await
+                });
+            }
+            None => {
+                warn!(
+                    id = weak_ref.id().to_string(),
+                    actor = "MessageRouter",
+                    event = "useragent.disconnected_before_approval"
+                );
+            }
+        }
+    }
+
+    while let Some(result) = pool.join_next().await {
+        match result {
+            Ok(Ok(approved)) => {
+                // cancel other pending requests
+                let _ = cancel_tx.send(());
+                return Ok(approved);
+            }
+            Ok(Err(err)) => {
+                warn!(
+                    ?err,
+                    actor = "MessageRouter",
+                    event = "useragent.approval_error"
+                );
+            }
+            Err(err) => {
+                warn!(
+                    ?err,
+                    actor = "MessageRouter",
+                    event = "useragent.approval_task_failed"
+                );
+            }
+        }
+    }
+
+    Err(ApprovalError::NoUserAgentsConnected)
+}
+
+#[messages]
+impl MessageRouter {
+    #[message(ctx)]
+    pub async fn register_user_agent(
+        &mut self,
+        actor: ActorRef<UserAgentSession>,
+        ctx: &mut Context<Self, ()>,
+    ) {
+        info!(id = %actor.id(), actor = "MessageRouter", event = "useragent.connected");
+        ctx.actor_ref().link(&actor).await;
+        self.user_agents.insert(actor.id(), actor);
+    }
+
+    #[message(ctx)]
+    pub async fn register_client(
+        &mut self,
+        actor: ActorRef<ClientSession>,
+        ctx: &mut Context<Self, ()>,
+    ) {
+        info!(id = %actor.id(), actor = "MessageRouter", event = "client.connected");
+        ctx.actor_ref().link(&actor).await;
+        self.clients.insert(actor.id(), actor);
+    }
+
+    #[message(ctx)]
+    pub async fn request_client_approval(
+        &mut self,
+        client_pubkey: VerifyingKey,
+        ctx: &mut Context<Self, DelegatedReply<Result<bool, ApprovalError>>>,
+    ) -> DelegatedReply<Result<bool, ApprovalError>> {
+        let (reply, Some(reply_sender)) = ctx.reply_sender() else {
+            unreachable!("Expected `request_client_approval` to have callback channel");
+        };
+
+        let weak_refs = self
+            .user_agents
+            .values()
+            .map(|agent| agent.downgrade())
+            .collect::<Vec<_>>();
+
+        tokio::task::spawn(async move {
+            let result = request_client_approval(&weak_refs, client_pubkey).await;
+            reply_sender.send(result);
+        });
+
+        reply
+    }
+}

server/crates/arbiter-server/src/actors/user_agent/auth.rs

@@ -1,19 +1,18 @@
-use super::{AuthenticatedOperator, OperatorConnection};
-use arbiter_crypto::authn::{self, AuthChallenge};
 use arbiter_proto::transport::Bi;
-
-use state::{
-    AuthContext, AuthError, AuthEvents, AuthStateMachine, AuthStates, ChallengeRequest,
-    ChallengeSolution,
-};
 use tracing::error;
 
+use crate::actors::user_agent::{
+    AuthPublicKey, UserAgentConnection,
+    auth::state::{AuthContext, AuthStateMachine},
+};
+
 mod state;
+use state::*;
 
 #[derive(Debug, Clone)]
 pub enum Inbound {
     AuthChallengeRequest {
-        pubkey: authn::PublicKey,
+        pubkey: AuthPublicKey,
         bootstrap_token: Option<String>,
     },
     AuthChallengeSolution {
@@ -38,16 +37,9 @@ impl Error {
     }
 }
 
-impl From<diesel::result::Error> for Error {
-    fn from(e: diesel::result::Error) -> Self {
-        error!(?e, "Database error");
-        Self::internal("Database error")
-    }
-}
-
 #[derive(Debug, Clone)]
 pub enum Outbound {
-    AuthChallenge { challenge: AuthChallenge },
+    AuthChallenge { nonce: i32 },
     AuthSuccess,
 }
 
@@ -55,11 +47,12 @@ fn parse_auth_event(payload: Inbound) -> AuthEvents {
     match payload {
         Inbound::AuthChallengeRequest {
             pubkey,
-            bootstrap_token,
-        } => AuthEvents::AuthRequest(ChallengeRequest {
+            bootstrap_token: None,
+        } => AuthEvents::AuthRequest(ChallengeRequest { pubkey }),
+        Inbound::AuthChallengeRequest {
             pubkey,
-            bootstrap_token,
-        }),
+            bootstrap_token: Some(token),
+        } => AuthEvents::BootstrapAuthRequest(BootstrapAuthRequest { pubkey, token }),
         Inbound::AuthChallengeSolution { signature } => {
             AuthEvents::ReceivedSolution(ChallengeSolution {
                 solution: signature,
@@ -69,21 +62,22 @@ fn parse_auth_event(payload: Inbound) -> AuthEvents {
 }
 
 pub async fn authenticate<T>(
-    props: &mut OperatorConnection,
-    transport: &mut T,
-) -> Result<AuthenticatedOperator, Error>
+    props: &mut UserAgentConnection,
+    transport: T,
+) -> Result<AuthPublicKey, Error>
 where
-    T: Bi<Inbound, Result<Outbound, Error>> + Send + ?Sized,
+    T: Bi<Inbound, Result<Outbound, Error>> + Send,
 {
     let mut state = AuthStateMachine::new(AuthContext::new(props, transport));
 
     loop {
+        // `state` holds a mutable reference to `props` so we can't access it directly here
         let Some(payload) = state.context_mut().transport.recv().await else {
             return Err(Error::Transport);
         };
 
         match state.process_event(parse_auth_event(payload)).await {
-            Ok(AuthStates::AuthOk(result)) => return Ok(result.clone()),
+            Ok(AuthStates::AuthOk(key)) => return Ok(key.clone()),
             Err(AuthError::ActionFailed(err)) => {
                 error!(?err, "State machine action failed");
                 return Err(err);

server/crates/arbiter-server/src/actors/user_agent/auth/state.rs

@@ -0,0 +1,222 @@
+use arbiter_proto::transport::Bi;
+use diesel::{ExpressionMethods as _, OptionalExtension as _, QueryDsl, update};
+use diesel_async::RunQueryDsl;
+use tracing::error;
+
+use super::Error;
+use crate::{
+    actors::{
+        bootstrap::ConsumeToken,
+        user_agent::{AuthPublicKey, UserAgentConnection, auth::Outbound},
+    },
+    db::schema,
+};
+
+pub struct ChallengeRequest {
+    pub pubkey: AuthPublicKey,
+}
+
+pub struct BootstrapAuthRequest {
+    pub pubkey: AuthPublicKey,
+    pub token: String,
+}
+
+pub struct ChallengeContext {
+    pub challenge_nonce: i32,
+    pub key: AuthPublicKey,
+}
+
+pub struct ChallengeSolution {
+    pub solution: Vec<u8>,
+}
+
+smlang::statemachine!(
+    name: Auth,
+    custom_error: true,
+    transitions: {
+        *Init + AuthRequest(ChallengeRequest) / async prepare_challenge = SentChallenge(ChallengeContext),
+        Init + BootstrapAuthRequest(BootstrapAuthRequest) / async verify_bootstrap_token = AuthOk(AuthPublicKey),
+        SentChallenge(ChallengeContext) + ReceivedSolution(ChallengeSolution) / async verify_solution = AuthOk(AuthPublicKey),
+    }
+);
+
+async fn create_nonce(db: &crate::db::DatabasePool, pubkey_bytes: &[u8]) -> Result<i32, Error> {
+    let mut db_conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::internal("Database unavailable")
+    })?;
+    db_conn
+        .exclusive_transaction(|conn| {
+            Box::pin(async move {
+                let current_nonce = schema::useragent_client::table
+                    .filter(schema::useragent_client::public_key.eq(pubkey_bytes.to_vec()))
+                    .select(schema::useragent_client::nonce)
+                    .first::<i32>(conn)
+                    .await?;
+
+                update(schema::useragent_client::table)
+                    .filter(schema::useragent_client::public_key.eq(pubkey_bytes.to_vec()))
+                    .set(schema::useragent_client::nonce.eq(current_nonce + 1))
+                    .execute(conn)
+                    .await?;
+
+                Result::<_, diesel::result::Error>::Ok(current_nonce)
+            })
+        })
+        .await
+        .optional()
+        .map_err(|e| {
+            error!(error = ?e, "Database error");
+            Error::internal("Database operation failed")
+        })?
+        .ok_or_else(|| {
+            error!(?pubkey_bytes, "Public key not found in database");
+            Error::UnregisteredPublicKey
+        })
+}
+
+async fn register_key(db: &crate::db::DatabasePool, pubkey: &AuthPublicKey) -> Result<(), Error> {
+    let pubkey_bytes = pubkey.to_stored_bytes();
+    let key_type = pubkey.key_type();
+    let mut conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::internal("Database unavailable")
+    })?;
+
+    diesel::insert_into(schema::useragent_client::table)
+        .values((
+            schema::useragent_client::public_key.eq(pubkey_bytes),
+            schema::useragent_client::nonce.eq(1),
+            schema::useragent_client::key_type.eq(key_type),
+        ))
+        .execute(&mut conn)
+        .await
+        .map_err(|e| {
+            error!(error = ?e, "Database error");
+            Error::internal("Database operation failed")
+        })?;
+
+    Ok(())
+}
+
+pub struct AuthContext<'a, T> {
+    pub(super) conn: &'a mut UserAgentConnection,
+    pub(super) transport: T,
+}
+
+impl<'a, T> AuthContext<'a, T> {
+    pub fn new(conn: &'a mut UserAgentConnection, transport: T) -> Self {
+        Self { conn, transport }
+    }
+}
+
+impl<T> AuthStateMachineContext for AuthContext<'_, T>
+where
+    T: Bi<super::Inbound, Result<super::Outbound, Error>> + Send,
+{
+    type Error = Error;
+
+    async fn prepare_challenge(
+        &mut self,
+        ChallengeRequest { pubkey }: ChallengeRequest,
+    ) -> Result<ChallengeContext, Self::Error> {
+        let stored_bytes = pubkey.to_stored_bytes();
+        let nonce = create_nonce(&self.conn.db, &stored_bytes).await?;
+
+        self.transport
+            .send(Ok(Outbound::AuthChallenge { nonce }))
+            .await
+            .map_err(|e| {
+                error!(?e, "Failed to send auth challenge");
+                Error::Transport
+            })?;
+
+        Ok(ChallengeContext {
+            challenge_nonce: nonce,
+            key: pubkey,
+        })
+    }
+
+    #[allow(missing_docs)]
+    #[allow(clippy::result_unit_err)]
+    async fn verify_bootstrap_token(
+        &mut self,
+        BootstrapAuthRequest { pubkey, token }: BootstrapAuthRequest,
+    ) -> Result<AuthPublicKey, Self::Error> {
+        let token_ok: bool = self
+            .conn
+            .actors
+            .bootstrapper
+            .ask(ConsumeToken {
+                token: token.clone(),
+            })
+            .await
+            .map_err(|e| {
+                error!(?e, "Failed to consume bootstrap token");
+                Error::internal("Failed to consume bootstrap token")
+            })?;
+
+        if !token_ok {
+            error!("Invalid bootstrap token provided");
+            return Err(Error::InvalidBootstrapToken);
+        }
+
+        register_key(&self.conn.db, &pubkey).await?;
+
+        self.transport
+            .send(Ok(Outbound::AuthSuccess))
+            .await
+            .map_err(|_| Error::Transport)?;
+
+        Ok(pubkey)
+    }
+
+    #[allow(missing_docs)]
+    #[allow(clippy::unused_unit)]
+    async fn verify_solution(
+        &mut self,
+        ChallengeContext {
+            challenge_nonce,
+            key,
+        }: &ChallengeContext,
+        ChallengeSolution { solution }: ChallengeSolution,
+    ) -> Result<AuthPublicKey, Self::Error> {
+        let formatted = arbiter_proto::format_challenge(*challenge_nonce, &key.to_stored_bytes());
+
+        let valid = match key {
+            AuthPublicKey::Ed25519(vk) => {
+                let sig = solution.as_slice().try_into().map_err(|_| {
+                    error!(?solution, "Invalid Ed25519 signature length");
+                    Error::InvalidChallengeSolution
+                })?;
+                vk.verify_strict(&formatted, &sig).is_ok()
+            }
+            AuthPublicKey::EcdsaSecp256k1(vk) => {
+                use k256::ecdsa::signature::Verifier as _;
+                let sig = k256::ecdsa::Signature::try_from(solution.as_slice()).map_err(|_| {
+                    error!(?solution, "Invalid ECDSA signature bytes");
+                    Error::InvalidChallengeSolution
+                })?;
+                vk.verify(&formatted, &sig).is_ok()
+            }
+            AuthPublicKey::Rsa(pk) => {
+                use rsa::signature::Verifier as _;
+                let verifying_key = rsa::pss::VerifyingKey::<sha2::Sha256>::new(pk.clone());
+                let sig = rsa::pss::Signature::try_from(solution.as_slice()).map_err(|_| {
+                    error!(?solution, "Invalid RSA signature bytes");
+                    Error::InvalidChallengeSolution
+                })?;
+                verifying_key.verify(&formatted, &sig).is_ok()
+            }
+        };
+
+        if valid {
+            self.transport
+                .send(Ok(Outbound::AuthSuccess))
+                .await
+                .map_err(|_| Error::Transport)?;
+        }
+
+        Ok(key.clone())
+    }
+}

server/crates/arbiter-server/src/actors/user_agent/mod.rs

@@ -0,0 +1,94 @@
+use crate::{
+    actors::GlobalActors,
+    db::{self, models::KeyType},
+};
+
+/// Abstraction over Ed25519 / ECDSA-secp256k1 / RSA public keys used during the auth handshake.
+#[derive(Clone, Debug)]
+pub enum AuthPublicKey {
+    Ed25519(ed25519_dalek::VerifyingKey),
+    /// Compressed SEC1 public key; signature bytes are raw 64-byte (r||s).
+    EcdsaSecp256k1(k256::ecdsa::VerifyingKey),
+    /// RSA-2048+ public key (Windows Hello / KeyCredentialManager); signature bytes are PSS+SHA-256.
+    Rsa(rsa::RsaPublicKey),
+}
+
+impl AuthPublicKey {
+    /// Canonical bytes stored in DB and echoed back in the challenge.
+    /// Ed25519: raw 32 bytes. ECDSA: SEC1 compressed 33 bytes. RSA: DER-encoded SPKI.
+    pub fn to_stored_bytes(&self) -> Vec<u8> {
+        match self {
+            AuthPublicKey::Ed25519(k) => k.to_bytes().to_vec(),
+            // SEC1 compressed (33 bytes) is the natural compact format for secp256k1
+            AuthPublicKey::EcdsaSecp256k1(k) => k.to_encoded_point(true).as_bytes().to_vec(),
+            AuthPublicKey::Rsa(k) => {
+                use rsa::pkcs8::EncodePublicKey as _;
+                #[allow(clippy::expect_used)]
+                k.to_public_key_der()
+                    .expect("rsa SPKI encoding is infallible")
+                    .to_vec()
+            }
+        }
+    }
+
+    pub fn key_type(&self) -> KeyType {
+        match self {
+            AuthPublicKey::Ed25519(_) => KeyType::Ed25519,
+            AuthPublicKey::EcdsaSecp256k1(_) => KeyType::EcdsaSecp256k1,
+            AuthPublicKey::Rsa(_) => KeyType::Rsa,
+        }
+    }
+}
+
+impl TryFrom<(KeyType, Vec<u8>)> for AuthPublicKey {
+    type Error = &'static str;
+
+    fn try_from(value: (KeyType, Vec<u8>)) -> Result<Self, Self::Error> {
+        let (key_type, bytes) = value;
+        match key_type {
+            KeyType::Ed25519 => {
+                let bytes: [u8; 32] = bytes.try_into().map_err(|_| "invalid Ed25519 key length")?;
+                let key = ed25519_dalek::VerifyingKey::from_bytes(&bytes)
+                    .map_err(|_e| "invalid Ed25519 key")?;
+                Ok(AuthPublicKey::Ed25519(key))
+            }
+            KeyType::EcdsaSecp256k1 => {
+                let point =
+                    k256::EncodedPoint::from_bytes(&bytes).map_err(|_e| "invalid ECDSA key")?;
+                let key = k256::ecdsa::VerifyingKey::from_encoded_point(&point)
+                    .map_err(|_e| "invalid ECDSA key")?;
+                Ok(AuthPublicKey::EcdsaSecp256k1(key))
+            }
+            KeyType::Rsa => {
+                use rsa::pkcs8::DecodePublicKey as _;
+                let key = rsa::RsaPublicKey::from_public_key_der(&bytes)
+                    .map_err(|_e| "invalid RSA key")?;
+                Ok(AuthPublicKey::Rsa(key))
+            }
+        }
+    }
+}
+
+// Messages, sent by user agent to connection client without having a request
+#[derive(Debug)]
+pub enum OutOfBand {
+    ClientConnectionRequest { pubkey: ed25519_dalek::VerifyingKey },
+    ClientConnectionCancel,
+}
+
+pub struct UserAgentConnection {
+    pub(crate) db: db::DatabasePool,
+    pub(crate) actors: GlobalActors,
+}
+
+impl UserAgentConnection {
+    pub fn new(db: db::DatabasePool, actors: GlobalActors) -> Self {
+        Self { db, actors }
+    }
+}
+
+pub mod auth;
+pub mod session;
+
+pub use auth::authenticate;
+pub use session::UserAgentSession;

server/crates/arbiter-server/src/actors/user_agent/session.rs

@@ -0,0 +1,132 @@
+use std::borrow::Cow;
+
+use arbiter_proto::transport::Sender;
+use async_trait::async_trait;
+use ed25519_dalek::VerifyingKey;
+use kameo::{Actor, messages};
+use thiserror::Error;
+use tokio::sync::watch;
+use tracing::error;
+
+use crate::actors::{
+    router::RegisterUserAgent,
+    user_agent::{OutOfBand, UserAgentConnection},
+};
+
+mod state;
+use state::{DummyContext, UserAgentEvents, UserAgentStateMachine};
+
+#[derive(Debug, Error)]
+pub enum Error {
+    #[error("State transition failed")]
+    State,
+
+    #[error("Internal error: {message}")]
+    Internal { message: Cow<'static, str> },
+}
+
+impl Error {
+    pub fn internal(message: impl Into<Cow<'static, str>>) -> Self {
+        Self::Internal {
+            message: message.into(),
+        }
+    }
+}
+
+pub struct UserAgentSession {
+    props: UserAgentConnection,
+    state: UserAgentStateMachine<DummyContext>,
+    #[allow(dead_code, reason = "The session keeps ownership of the outbound transport even before the state-machine flow starts using it directly")]
+    sender: Box<dyn Sender<OutOfBand>>,
+}
+
+mod connection;
+pub(crate) use connection::{
+    BootstrapError, HandleBootstrapEncryptedKey, HandleEvmWalletCreate, HandleEvmWalletList,
+    HandleGrantCreate, HandleGrantDelete, HandleGrantList, HandleQueryVaultState,
+};
+pub use connection::{HandleUnsealEncryptedKey, HandleUnsealRequest, UnsealError};
+
+impl UserAgentSession {
+    pub(crate) fn new(props: UserAgentConnection, sender: Box<dyn Sender<OutOfBand>>) -> Self {
+        Self {
+            props,
+            state: UserAgentStateMachine::new(DummyContext),
+            sender,
+        }
+    }
+
+    pub fn new_test(db: crate::db::DatabasePool, actors: crate::actors::GlobalActors) -> Self {
+        struct DummySender;
+
+        #[async_trait]
+        impl Sender<OutOfBand> for DummySender {
+            async fn send(
+                &mut self,
+                _item: OutOfBand,
+            ) -> Result<(), arbiter_proto::transport::Error> {
+                Ok(())
+            }
+        }
+
+        Self::new(UserAgentConnection::new(db, actors), Box::new(DummySender))
+    }
+
+    fn transition(&mut self, event: UserAgentEvents) -> Result<(), Error> {
+        self.state.process_event(event).map_err(|e| {
+            error!(?e, "State transition failed");
+            Error::State
+        })?;
+        Ok(())
+    }
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message]
+    pub async fn request_new_client_approval(
+        &mut self,
+        client_pubkey: VerifyingKey,
+        mut cancel_flag: watch::Receiver<()>,
+    ) -> Result<bool, ()> {
+        if self
+            .sender
+            .send(OutOfBand::ClientConnectionRequest {
+                pubkey: client_pubkey,
+            })
+            .await
+            .is_err()
+        {
+            return Err(());
+        }
+
+        let _ = cancel_flag.changed().await;
+
+        let _ = self.sender.send(OutOfBand::ClientConnectionCancel).await;
+        Ok(false)
+    }
+}
+
+impl Actor for UserAgentSession {
+    type Args = Self;
+
+    type Error = Error;
+
+    async fn on_start(
+        args: Self::Args,
+        this: kameo::prelude::ActorRef<Self>,
+    ) -> Result<Self, Self::Error> {
+        args.props
+            .actors
+            .router
+            .ask(RegisterUserAgent {
+                actor: this.clone(),
+            })
+            .await
+            .map_err(|err| {
+                error!(?err, "Failed to register user agent connection with router");
+                Error::internal("Failed to register user agent connection with router")
+            })?;
+        Ok(args)
+    }
+}

server/crates/arbiter-server/src/actors/user_agent/session/connection.rs

@@ -0,0 +1,354 @@
+use std::sync::Mutex;
+
+use alloy::primitives::Address;
+use chacha20poly1305::{AeadInPlace, XChaCha20Poly1305, XNonce, aead::KeyInit};
+use kameo::error::SendError;
+use kameo::messages;
+use tracing::{error, info};
+use x25519_dalek::{EphemeralSecret, PublicKey};
+
+use crate::actors::keyholder::KeyHolderState;
+use crate::actors::user_agent::session::Error;
+use crate::evm::policies::{Grant, SpecificGrant};
+use crate::safe_cell::SafeCell;
+use crate::{
+    actors::{
+        evm::{
+            Generate, ListWallets, UseragentCreateGrant, UseragentDeleteGrant, UseragentListGrants,
+        },
+        keyholder::{self, Bootstrap, TryUnseal},
+        user_agent::session::{
+                UserAgentSession,
+                state::{UnsealContext, UserAgentEvents, UserAgentStates},
+            },
+    },
+    safe_cell::SafeCellHandle as _,
+};
+
+impl UserAgentSession {
+    fn take_unseal_secret(&mut self) -> Result<(EphemeralSecret, PublicKey), Error> {
+        let UserAgentStates::WaitingForUnsealKey(unseal_context) = self.state.state() else {
+            error!("Received encrypted key in invalid state");
+            return Err(Error::internal("Invalid state for unseal encrypted key"));
+        };
+
+        let ephemeral_secret = {
+            #[allow(
+                clippy::unwrap_used,
+                reason = "Mutex poison is unrecoverable and should panic"
+            )]
+            let mut secret_lock = unseal_context.secret.lock().unwrap();
+            let secret = secret_lock.take();
+            match secret {
+                Some(secret) => secret,
+                None => {
+                    drop(secret_lock);
+                    error!("Ephemeral secret already taken");
+                    return Err(Error::internal("Ephemeral secret already taken"));
+                }
+            }
+        };
+
+        Ok((ephemeral_secret, unseal_context.client_public_key))
+    }
+
+    fn decrypt_client_key_material(
+        ephemeral_secret: EphemeralSecret,
+        client_public_key: PublicKey,
+        nonce: &[u8],
+        ciphertext: &[u8],
+        associated_data: &[u8],
+    ) -> Result<SafeCell<Vec<u8>>, ()> {
+        let nonce = XNonce::from_slice(nonce);
+
+        let shared_secret = ephemeral_secret.diffie_hellman(&client_public_key);
+        let cipher = XChaCha20Poly1305::new(shared_secret.as_bytes().into());
+
+        let mut key_buffer = SafeCell::new(ciphertext.to_vec());
+
+        let decryption_result = key_buffer.write_inline(|write_handle| {
+            cipher.decrypt_in_place(nonce, associated_data, write_handle)
+        });
+
+        match decryption_result {
+            Ok(_) => Ok(key_buffer),
+            Err(err) => {
+                error!(?err, "Failed to decrypt encrypted key material");
+                Err(())
+            }
+        }
+    }
+}
+
+pub struct UnsealStartResponse {
+    pub server_pubkey: PublicKey,
+}
+
+#[derive(Debug, Error)]
+pub enum UnsealError {
+    #[error("Invalid key provided for unsealing")]
+    InvalidKey,
+    #[error("Internal error during unsealing process")]
+    General(#[from] super::Error),
+}
+
+#[derive(Debug, Error)]
+pub enum BootstrapError {
+    #[error("Invalid key provided for bootstrapping")]
+    InvalidKey,
+    #[error("Vault is already bootstrapped")]
+    AlreadyBootstrapped,
+
+    #[error("Internal error during bootstrapping process")]
+    General(#[from] super::Error),
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message]
+    pub async fn handle_unseal_request(
+        &mut self,
+        client_pubkey: x25519_dalek::PublicKey,
+    ) -> Result<UnsealStartResponse, Error> {
+        let secret = EphemeralSecret::random();
+        let public_key = PublicKey::from(&secret);
+
+        self.transition(UserAgentEvents::UnsealRequest(UnsealContext {
+            secret: Mutex::new(Some(secret)),
+            client_public_key: client_pubkey,
+        }))?;
+
+        Ok(UnsealStartResponse {
+            server_pubkey: public_key,
+        })
+    }
+
+    #[message]
+    pub async fn handle_unseal_encrypted_key(
+        &mut self,
+        nonce: Vec<u8>,
+        ciphertext: Vec<u8>,
+        associated_data: Vec<u8>,
+    ) -> Result<(), UnsealError> {
+        let (ephemeral_secret, client_public_key) = match self.take_unseal_secret() {
+            Ok(values) => values,
+            Err(Error::State) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                return Err(UnsealError::InvalidKey);
+            }
+            Err(_err) => {
+                return Err(Error::internal("Failed to take unseal secret").into());
+            }
+        };
+
+        let seal_key_buffer = match Self::decrypt_client_key_material(
+            ephemeral_secret,
+            client_public_key,
+            &nonce,
+            &ciphertext,
+            &associated_data,
+        ) {
+            Ok(buffer) => buffer,
+            Err(()) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                return Err(UnsealError::InvalidKey);
+            }
+        };
+
+        match self
+            .props
+            .actors
+            .key_holder
+            .ask(TryUnseal {
+                seal_key_raw: seal_key_buffer,
+            })
+            .await
+        {
+            Ok(_) => {
+                info!("Successfully unsealed key with client-provided key");
+                self.transition(UserAgentEvents::ReceivedValidKey)?;
+                Ok(())
+            }
+            Err(SendError::HandlerError(keyholder::Error::InvalidKey)) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(UnsealError::InvalidKey)
+            }
+            Err(SendError::HandlerError(err)) => {
+                error!(?err, "Keyholder failed to unseal key");
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(UnsealError::InvalidKey)
+            }
+            Err(err) => {
+                error!(?err, "Failed to send unseal request to keyholder");
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(Error::internal("Vault actor error").into())
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_bootstrap_encrypted_key(
+        &mut self,
+        nonce: Vec<u8>,
+        ciphertext: Vec<u8>,
+        associated_data: Vec<u8>,
+    ) -> Result<(), BootstrapError> {
+        let (ephemeral_secret, client_public_key) = match self.take_unseal_secret() {
+            Ok(values) => values,
+            Err(Error::State) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                return Err(BootstrapError::InvalidKey);
+            }
+            Err(err) => return Err(err.into()),
+        };
+
+        let seal_key_buffer = match Self::decrypt_client_key_material(
+            ephemeral_secret,
+            client_public_key,
+            &nonce,
+            &ciphertext,
+            &associated_data,
+        ) {
+            Ok(buffer) => buffer,
+            Err(()) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                return Err(BootstrapError::InvalidKey);
+            }
+        };
+
+        match self
+            .props
+            .actors
+            .key_holder
+            .ask(Bootstrap {
+                seal_key_raw: seal_key_buffer,
+            })
+            .await
+        {
+            Ok(_) => {
+                info!("Successfully bootstrapped vault with client-provided key");
+                self.transition(UserAgentEvents::ReceivedValidKey)?;
+                Ok(())
+            }
+            Err(SendError::HandlerError(keyholder::Error::AlreadyBootstrapped)) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(BootstrapError::AlreadyBootstrapped)
+            }
+            Err(SendError::HandlerError(err)) => {
+                error!(?err, "Keyholder failed to bootstrap vault");
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(BootstrapError::InvalidKey)
+            }
+            Err(err) => {
+                error!(?err, "Failed to send bootstrap request to keyholder");
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(BootstrapError::General(Error::internal(
+                    "Vault actor error",
+                )))
+            }
+        }
+    }
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message]
+    pub(crate) async fn handle_query_vault_state(&mut self) -> Result<KeyHolderState, Error> {
+        use crate::actors::keyholder::GetState;
+
+        let vault_state = match self.props.actors.key_holder.ask(GetState {}).await {
+            Ok(state) => state,
+            Err(err) => {
+                error!(?err, actor = "useragent", "keyholder.query.failed");
+                return Err(Error::internal("Vault is in broken state"));
+            }
+        };
+
+        Ok(vault_state)
+    }
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message]
+    pub(crate) async fn handle_evm_wallet_create(&mut self) -> Result<Address, Error> {
+        match self.props.actors.evm.ask(Generate {}).await {
+            Ok(address) => Ok(address),
+            Err(SendError::HandlerError(err)) => Err(Error::internal(format!(
+                "EVM wallet generation failed: {err}"
+            ))),
+            Err(err) => {
+                error!(?err, "EVM actor unreachable during wallet create");
+                Err(Error::internal("EVM actor unreachable"))
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_evm_wallet_list(&mut self) -> Result<Vec<Address>, Error> {
+        match self.props.actors.evm.ask(ListWallets {}).await {
+            Ok(wallets) => Ok(wallets),
+            Err(err) => {
+                error!(?err, "EVM wallet list failed");
+                Err(Error::internal("Failed to list EVM wallets"))
+            }
+        }
+    }
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message]
+    pub(crate) async fn handle_grant_list(&mut self) -> Result<Vec<Grant<SpecificGrant>>, Error> {
+        match self.props.actors.evm.ask(UseragentListGrants {}).await {
+            Ok(grants) => Ok(grants),
+            Err(err) => {
+                error!(?err, "EVM grant list failed");
+                Err(Error::internal("Failed to list EVM grants"))
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_grant_create(
+        &mut self,
+        client_id: i32,
+        basic: crate::evm::policies::SharedGrantSettings,
+        grant: crate::evm::policies::SpecificGrant,
+    ) -> Result<i32, Error> {
+        match self
+            .props
+            .actors
+            .evm
+            .ask(UseragentCreateGrant {
+                client_id,
+                basic,
+                grant,
+            })
+            .await
+        {
+            Ok(grant_id) => Ok(grant_id),
+            Err(err) => {
+                error!(?err, "EVM grant create failed");
+                Err(Error::internal("Failed to create EVM grant"))
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_grant_delete(&mut self, grant_id: i32) -> Result<(), Error> {
+        match self
+            .props
+            .actors
+            .evm
+            .ask(UseragentDeleteGrant { grant_id })
+            .await
+        {
+            Ok(()) => Ok(()),
+            Err(err) => {
+                error!(?err, "EVM grant delete failed");
+                Err(Error::internal("Failed to delete EVM grant"))
+            }
+        }
+    }
+}

server/crates/arbiter-server/src/actors/user_agent/session/state.rs

@@ -0,0 +1,27 @@
+use std::sync::Mutex;
+
+use x25519_dalek::{EphemeralSecret, PublicKey};
+
+pub struct UnsealContext {
+    pub client_public_key: PublicKey,
+    pub secret: Mutex<Option<EphemeralSecret>>,
+}
+
+smlang::statemachine!(
+    name: UserAgent,
+    custom_error: false,
+    transitions: {
+        *Idle + UnsealRequest(UnsealContext) / generate_temp_keypair = WaitingForUnsealKey(UnsealContext),
+        WaitingForUnsealKey(UnsealContext) + ReceivedValidKey = Unsealed,
+        WaitingForUnsealKey(UnsealContext) + ReceivedInvalidKey = Idle,
+    }
+);
+
+pub struct DummyContext;
+impl UserAgentStateMachineContext for DummyContext {
+    #[allow(missing_docs)]
+    #[allow(clippy::unused_unit)]
+    fn generate_temp_keypair(&mut self, event_data: UnsealContext) -> Result<UnsealContext, ()> {
+        Ok(event_data)
+    }
+}

server/crates/arbiter-server/src/actors/vault/mod.rs

@@ -1,673 +0,0 @@
-use crate::{
-    actors::proposal_manager::events::ProposalApproved,
-    crypto::{
-        KeyCell,
-        encryption::v1::{self, Nonce},
-        integrity::{self, v1::HmacSha256},
-    },
-    db::{
-        self,
-        models::{self, RootKeyHistory, RootKeyHistoryId},
-        proposal::ProposalKind,
-        schema,
-    },
-};
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
-use chrono::Utc;
-use diesel::{
-    ExpressionMethods as _, OptionalExtension, QueryDsl, SelectableHelper,
-    dsl::{insert_into, update},
-};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use hmac::{KeyInit as _, Mac as _};
-use kameo::{Actor, Reply, actor::ActorRef, messages, prelude::Message};
-use kameo_actors::message_bus::{MessageBus, Publish};
-use strum::{EnumDiscriminants, IntoDiscriminant};
-use tracing::{error, info};
-
-pub mod events {
-    #[derive(Clone, Copy)]
-    pub struct Bootstrapped;
-
-    #[derive(Clone, Copy)]
-    pub struct Unsealed;
-
-    #[derive(Clone, Copy)]
-    pub struct VaultResealed;
-}
-
-#[derive(Debug, thiserror::Error)]
-pub enum Error {
-    #[error("Vault is already bootstrapped")]
-    AlreadyBootstrapped,
-    #[error("Vault is not bootstrapped")]
-    NotBootstrapped,
-    #[error("Vault is sealed")]
-    Sealed,
-    #[error("Invalid key provided")]
-    InvalidKey,
-
-    #[error("Requested aead entry not found")]
-    NotFound,
-
-    #[error("Encryption error: {0}")]
-    Encryption(#[from] chacha20poly1305::aead::Error),
-
-    #[error("Database error: {0}")]
-    DatabaseConnection(#[from] db::PoolError),
-
-    #[error("Database transaction error: {0}")]
-    DatabaseTransaction(#[from] diesel::result::Error),
-
-    #[error("Broken database")]
-    BrokenDatabase,
-}
-
-struct Unsealed {
-    root_key_history_id: RootKeyHistoryId,
-    root_key: KeyCell,
-}
-
-#[derive(Default, EnumDiscriminants)]
-#[strum_discriminants(derive(Reply), vis(pub), name(VaultState))]
-enum State {
-    #[default]
-    Unbootstrapped,
-
-    Sealed {
-        root_key_history_id: RootKeyHistoryId,
-    },
-    Unsealed(Unsealed),
-}
-
-/// Manages vault root key and tracks current state of the vault (bootstrapped/unbootstrapped, sealed/unsealed).
-///
-/// Provides API for encrypting and decrypting data using the vault root key.
-/// Abstraction over database to make sure nonces are never reused and encryption keys are never exposed in plaintext outside of this actor.
-#[derive(Actor)]
-pub struct Vault {
-    db: db::DatabasePool,
-    state: State,
-    events: ActorRef<MessageBus>,
-}
-
-impl Vault {
-    pub async fn new(db: db::DatabasePool, events: ActorRef<MessageBus>) -> Result<Self, Error> {
-        let state = {
-            let mut conn = db.get().await?;
-
-            let (root_key_history,) = schema::arbiter_settings::table
-                .left_join(schema::root_key_history::table)
-                .select((Option::<RootKeyHistory>::as_select(),))
-                .get_result::<(Option<RootKeyHistory>,)>(&mut conn)
-                .await?;
-
-            match root_key_history {
-                Some(root_key_history) => State::Sealed {
-                    root_key_history_id: root_key_history.id,
-                },
-                None => State::Unbootstrapped,
-            }
-        };
-
-        Ok(Self { db, state, events })
-    }
-
-    // Exclusive transaction to avoid race conditions if multiple vaults write
-    // additional layer of protection against nonce-reuse
-    async fn get_new_nonce(
-        pool: &db::DatabasePool,
-        root_key_id: RootKeyHistoryId,
-    ) -> Result<Nonce, Error> {
-        let mut conn = pool.get().await?;
-
-        let nonce = conn
-            .exclusive_transaction(async |conn| {
-                let current_nonce: Vec<u8> = schema::root_key_history::table
-                    .filter(schema::root_key_history::id.eq(root_key_id))
-                    .select(schema::root_key_history::data_encryption_nonce)
-                    .first(&mut *conn)
-                    .await?;
-
-                let mut nonce = Nonce::try_from(current_nonce.as_slice()).map_err(|()| {
-                    error!(
-                        "Broken database: invalid nonce for root key history id={:#?}",
-                        root_key_id
-                    );
-                    Error::BrokenDatabase
-                })?;
-                nonce.increment();
-
-                update(schema::root_key_history::table)
-                    .filter(schema::root_key_history::id.eq(root_key_id))
-                    .set(schema::root_key_history::data_encryption_nonce.eq(nonce.to_vec()))
-                    .execute(&mut *conn)
-                    .await?;
-
-                Result::<_, Error>::Ok(nonce)
-            })
-            .await?;
-
-        Ok(nonce)
-    }
-
-    const fn expect_unsealed(state: &mut State) -> Result<&mut Unsealed, Error> {
-        match state {
-            State::Unsealed(unsealed) => Ok(unsealed),
-            State::Unbootstrapped => Err(Error::NotBootstrapped),
-            State::Sealed { .. } => Err(Error::Sealed),
-        }
-    }
-}
-
-#[messages]
-impl Vault {
-    #[message]
-    pub async fn bootstrap(&mut self, mut seal_key: KeyCell) -> Result<(), Error> {
-        if !matches!(&self.state, State::Unbootstrapped) {
-            return Err(Error::AlreadyBootstrapped);
-        }
-
-        let mut root_key = KeyCell::new_secure_random();
-
-        // Zero nonces are fine because they are one-time
-        let root_key_nonce = Nonce::default();
-        let data_encryption_nonce = Nonce::default();
-
-        // Generate salt (kept for schema compat)
-        let root_key_salt = v1::generate_salt();
-
-        let root_key_ciphertext: Vec<u8> = root_key.0.read_inline(|rk| {
-            seal_key
-                .encrypt(&root_key_nonce, v1::ROOT_KEY_TAG, rk.as_slice())
-                .map_err(|err| {
-                    error!(?err, "Fatal bootstrap error");
-                    Error::Encryption(err)
-                })
-        })?;
-
-        let data_encryption_nonce_bytes = data_encryption_nonce.to_vec();
-        let mut conn = self.db.get().await?;
-
-        let root_key_history_id = conn
-            .transaction(async |conn| {
-                let root_key_history_id = insert_into(schema::root_key_history::table)
-                    .values(&models::NewRootKeyHistory {
-                        ciphertext: root_key_ciphertext.clone(),
-                        tag: v1::ROOT_KEY_TAG.to_vec(),
-                        root_key_encryption_nonce: root_key_nonce.to_vec(),
-                        data_encryption_nonce: data_encryption_nonce_bytes.clone(),
-                        schema_version: 1,
-                        salt: root_key_salt.to_vec(),
-                    })
-                    .returning(schema::root_key_history::id)
-                    .get_result(&mut *conn)
-                    .await?;
-
-                update(schema::arbiter_settings::table)
-                    .set(schema::arbiter_settings::root_key_id.eq(root_key_history_id))
-                    .execute(&mut *conn)
-                    .await?;
-
-                Result::<_, diesel::result::Error>::Ok(RootKeyHistoryId::from_raw(
-                    root_key_history_id,
-                ))
-            })
-            .await?;
-
-        self.state = State::Unsealed(Unsealed {
-            root_key,
-            root_key_history_id,
-        });
-
-        info!("Vault bootstrapped successfully");
-        if let Err(err) = self.events.tell(Publish(events::Bootstrapped)).await {
-            error!(?err, "Failed to publish Bootstrapped event");
-        }
-
-        Ok(())
-    }
-
-    #[message]
-    pub async fn try_unseal(&mut self, mut seal_key: KeyCell) -> Result<(), Error> {
-        let State::Sealed {
-            root_key_history_id,
-        } = &self.state
-        else {
-            return Err(Error::NotBootstrapped);
-        };
-        let root_key_history_id = *root_key_history_id;
-
-        // We don't want to hold connection while doing expensive work
-        let current_key = {
-            let mut conn = self.db.get().await?;
-            schema::root_key_history::table
-                .filter(schema::root_key_history::id.eq(root_key_history_id))
-                .select(RootKeyHistory::as_select())
-                .first(&mut conn)
-                .await?
-        };
-
-        let nonce =
-            Nonce::try_from(current_key.root_key_encryption_nonce.as_slice()).map_err(|()| {
-                error!("Broken database: invalid nonce for root key");
-                Error::BrokenDatabase
-            })?;
-
-        let mut root_key_bytes = SafeCell::new(current_key.ciphertext.clone());
-        seal_key
-            .decrypt_in_place(&nonce, v1::ROOT_KEY_TAG, &mut root_key_bytes)
-            .map_err(|err| {
-                error!(?err, "Failed to unseal root key: invalid seal key");
-                Error::InvalidKey
-            })?;
-
-        let root_key = KeyCell::try_from(root_key_bytes).map_err(|()| {
-            error!("Broken database: invalid encryption key size");
-            Error::BrokenDatabase
-        })?;
-
-        self.state = State::Unsealed(Unsealed {
-            root_key_history_id: current_key.id,
-            root_key,
-        });
-
-        info!("Vault unsealed successfully");
-        let _ = self.events.tell(Publish(events::Unsealed)).await;
-
-        Ok(())
-    }
-
-    /// Re-encrypts the root key with `new_seal_key`, updating its `root_key_history` row in
-    /// place. Called after a Shamir re-key, so the old seal key is no longer sufficient to
-    /// unseal. The root key itself does not change, so its row identity (and the nonce counter
-    /// and integrity envelopes bound to it) must not change either.
-    #[message]
-    pub async fn rekey_root_key(&mut self, mut new_seal_key: KeyCell) -> Result<(), Error> {
-        let Unsealed {
-            root_key,
-            root_key_history_id,
-        } = Self::expect_unsealed(&mut self.state)?;
-
-        let new_nonce = Nonce::default();
-        let new_salt = v1::generate_salt();
-
-        let new_ciphertext: Vec<u8> = root_key.0.read_inline(|rk| {
-            new_seal_key
-                .encrypt(&new_nonce, v1::ROOT_KEY_TAG, rk.as_slice())
-                .map_err(|err| {
-                    error!(?err, "Fatal rekey error");
-                    Error::Encryption(err)
-                })
-        })?;
-
-        let mut conn = self.db.get().await?;
-
-        // The root key is unchanged, so its row keeps its identity: `data_encryption_nonce`
-        // keeps counting up, and every integrity envelope stays bound to the same key version.
-        // Only the seal-key material is replaced, retiring the previous one. `tag` and
-        // `schema_version` are deliberately left untouched: the seal-key encryption scheme
-        // itself is unchanged by a re-key, so there is nothing new for them to describe.
-        let rows_updated = update(schema::root_key_history::table)
-            .filter(schema::root_key_history::id.eq(*root_key_history_id))
-            .set((
-                schema::root_key_history::ciphertext.eq(new_ciphertext),
-                schema::root_key_history::root_key_encryption_nonce.eq(new_nonce.to_vec()),
-                schema::root_key_history::salt.eq(new_salt.to_vec()),
-            ))
-            .execute(&mut conn)
-            .await?;
-
-        if rows_updated == 0 {
-            error!(
-                "Broken database: rekey matched no root_key_history row id={:#?}",
-                root_key_history_id
-            );
-            return Err(Error::BrokenDatabase);
-        }
-
-        info!("Vault root key rekeyed successfully");
-        Ok(())
-    }
-
-    #[message]
-    pub async fn seal(&mut self) -> Result<(), Error> {
-        let Unsealed {
-            root_key_history_id,
-            ..
-        } = Self::expect_unsealed(&mut self.state)?;
-
-        self.state = State::Sealed {
-            root_key_history_id: *root_key_history_id,
-        };
-        let _ = self.events.tell(Publish(events::VaultResealed)).await;
-        Ok(())
-    }
-}
-
-// Server-side cryptographic operations
-#[messages]
-impl Vault {
-    #[message]
-    pub async fn decrypt(&mut self, aead_id: i32) -> Result<SafeCell<Vec<u8>>, Error> {
-        let Unsealed { root_key, .. } = Self::expect_unsealed(&mut self.state)?;
-
-        let row: models::AeadEncrypted = {
-            let mut conn = self.db.get().await?;
-            schema::aead_encrypted::table
-                .select(models::AeadEncrypted::as_select())
-                .filter(schema::aead_encrypted::id.eq(aead_id))
-                .first(&mut conn)
-                .await
-                .optional()?
-                .ok_or(Error::NotFound)?
-        };
-
-        let nonce = Nonce::try_from(row.current_nonce.as_slice()).map_err(|()| {
-            error!(
-                "Broken database: invalid nonce for aead_encrypted id={}",
-                aead_id
-            );
-            Error::BrokenDatabase
-        })?;
-        let mut output = SafeCell::new(row.ciphertext);
-        root_key.decrypt_in_place(&nonce, v1::TAG, &mut output)?;
-        Ok(output)
-    }
-
-    // Creates new `aead_encrypted` entry in the database and returns it's ID
-    #[message]
-    pub async fn create_new(&mut self, mut plaintext: SafeCell<Vec<u8>>) -> Result<i32, Error> {
-        let Unsealed {
-            root_key,
-            root_key_history_id,
-        } = Self::expect_unsealed(&mut self.state)?;
-
-        // Order matters here - `get_new_nonce` acquires connection, so we need to call it before next acquire
-        // Borrow checker note: &mut borrow a few lines above is disjoint from this field
-        let nonce = Self::get_new_nonce(&self.db, *root_key_history_id).await?;
-
-        let mut ciphertext_buffer = plaintext.write();
-        let ciphertext_buffer: &mut Vec<u8> = ciphertext_buffer.as_mut();
-        root_key.encrypt_in_place(&nonce, v1::TAG, &mut *ciphertext_buffer)?;
-
-        let ciphertext = std::mem::take(ciphertext_buffer);
-
-        let mut conn = self.db.get().await?;
-        let aead_id: i32 = insert_into(schema::aead_encrypted::table)
-            .values(&models::NewAeadEncrypted {
-                ciphertext,
-                tag: v1::TAG.to_vec(),
-                current_nonce: nonce.to_vec(),
-                schema_version: 1,
-                associated_root_key_id: *root_key_history_id,
-                created_at: Utc::now().into(),
-            })
-            .returning(schema::aead_encrypted::id)
-            .get_result(&mut conn)
-            .await?;
-
-        Ok(aead_id)
-    }
-
-    #[message]
-    pub fn get_state(&self) -> VaultState {
-        self.state.discriminant()
-    }
-
-    #[message]
-    pub fn sign_integrity(
-        &mut self,
-        mac_input: Vec<u8>,
-    ) -> Result<(RootKeyHistoryId, Vec<u8>), Error> {
-        let Unsealed {
-            root_key,
-            root_key_history_id,
-        } = Self::expect_unsealed(&mut self.state)?;
-
-        let mut hmac = root_key.0.read_inline(|k| {
-            HmacSha256::new_from_slice(k)
-                .unwrap_or_else(|_| unreachable!("HMAC accepts keys of any size"))
-        });
-        hmac.update(&root_key_history_id.to_raw().to_be_bytes());
-        hmac.update(&mac_input);
-
-        let mac = hmac.finalize().into_bytes().to_vec();
-        Ok((*root_key_history_id, mac))
-    }
-
-    #[message]
-    pub fn verify_integrity(
-        &mut self,
-        mac_input: Vec<u8>,
-        expected_mac: Vec<u8>,
-        key_version: RootKeyHistoryId,
-    ) -> Result<bool, Error> {
-        let Unsealed {
-            root_key,
-            root_key_history_id,
-        } = Self::expect_unsealed(&mut self.state)?;
-
-        if *root_key_history_id != key_version {
-            return Ok(false);
-        }
-
-        let mut hmac = root_key.0.read_inline(|k| {
-            HmacSha256::new_from_slice(k)
-                .unwrap_or_else(|_| unreachable!("HMAC accepts keys of any size"))
-        });
-        hmac.update(&key_version.to_raw().to_be_bytes());
-        hmac.update(&mac_input);
-
-        Ok(hmac.verify_slice(&expected_mac).is_ok())
-    }
-}
-
-impl Message<ProposalApproved> for Vault {
-    type Reply = ();
-
-    /// Every subscriber sees every approval and acts only on the kinds it owns.
-    async fn handle(
-        &mut self,
-        msg: ProposalApproved,
-        _ctx: &mut kameo::prelude::Context<Self, Self::Reply>,
-    ) -> Self::Reply {
-        let ProposalKind::ApproveSdkClient(settings) = msg.kind else {
-            return;
-        };
-
-        if let Err(error) = self.approve_sdk_client(settings.client_id).await {
-            error!(
-                ?error,
-                proposal_id = msg.id.to_raw(),
-                "Failed to execute an approved proposal"
-            );
-        }
-    }
-}
-
-impl Vault {
-    /// Attests an approved SDK client with the root key.
-    ///
-    /// Builds the envelope from its parts rather than calling `integrity::sign_entity`,
-    /// which would have this actor ask itself for a signature and deadlock.
-    async fn approve_sdk_client(&mut self, client_id: i32) -> Result<(), Error> {
-        use crate::peers::client::ClientCredentials;
-        use arbiter_crypto::authn;
-
-        // Cloned so the connection does not hold a borrow of `self` across `sign_integrity`.
-        let db = self.db.clone();
-        let mut conn = db.get().await?;
-
-        let pubkey_bytes: Vec<u8> = schema::program_client::table
-            .find(client_id)
-            .select(schema::program_client::public_key)
-            .first(&mut conn)
-            .await?;
-
-        let pubkey =
-            authn::PublicKey::try_from(pubkey_bytes.as_slice()).map_err(|()| Error::InvalidKey)?;
-        let credentials = ClientCredentials { pubkey };
-
-        let (entity_id, mac_input) = integrity::envelope_input(&credentials, client_id);
-        let (key_version, mac) = self.sign_integrity(mac_input)?;
-
-        integrity::store_envelope::<ClientCredentials>(&mut conn, entity_id, key_version, mac)
-            .await?;
-
-        Ok(())
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use crate::actors::GlobalActors;
-
-    use super::*;
-
-    async fn bootstrapped_actor(db: &db::DatabasePool) -> Vault {
-        let mut actor = Vault::new(db.clone(), GlobalActors::spawn_message_bus())
-            .await
-            .unwrap();
-        actor.bootstrap(KeyCell::from([0u8; 32])).await.unwrap();
-        actor
-    }
-
-    #[tokio::test]
-    #[test_log::test]
-    async fn nonce_monotonic_even_when_nonce_allocation_interleaves() {
-        let db = db::create_test_pool().await;
-        let mut actor = bootstrapped_actor(&db).await;
-        let State::Unsealed(Unsealed {
-            root_key_history_id,
-            ..
-        }) = actor.state
-        else {
-            panic!("expected unsealed state");
-        };
-
-        let n1 = Vault::get_new_nonce(&db, root_key_history_id)
-            .await
-            .unwrap();
-        let n2 = Vault::get_new_nonce(&db, root_key_history_id)
-            .await
-            .unwrap();
-        assert!(n2.to_vec() > n1.to_vec(), "nonce must increase");
-
-        let mut conn = db.get().await.unwrap();
-        let root_row: RootKeyHistory = schema::root_key_history::table
-            .select(RootKeyHistory::as_select())
-            .first(&mut conn)
-            .await
-            .unwrap();
-        assert_eq!(root_row.data_encryption_nonce, n2.to_vec());
-
-        let id = actor
-            .create_new(SafeCell::new(b"post-interleave".to_vec()))
-            .await
-            .unwrap();
-        let row: models::AeadEncrypted = schema::aead_encrypted::table
-            .filter(schema::aead_encrypted::id.eq(id))
-            .select(models::AeadEncrypted::as_select())
-            .first(&mut conn)
-            .await
-            .unwrap();
-        assert!(
-            row.current_nonce > n2.to_vec(),
-            "next write must advance nonce"
-        );
-    }
-
-    #[tokio::test]
-    #[test_log::test]
-    async fn rekey_does_not_restart_the_data_nonce_counter() {
-        let db = db::create_test_pool().await;
-        let mut actor = bootstrapped_actor(&db).await;
-
-        let before = actor
-            .create_new(SafeCell::new(b"before-rekey".to_vec()))
-            .await
-            .unwrap();
-
-        actor.rekey_root_key(KeyCell::from([7u8; 32])).await.unwrap();
-
-        let after = actor
-            .create_new(SafeCell::new(b"after-rekey".to_vec()))
-            .await
-            .unwrap();
-
-        let mut conn = db.get().await.unwrap();
-
-        // One root key, one row: the root key never changed, so its history did not fork.
-        let rows: i64 = schema::root_key_history::table
-            .count()
-            .get_result(&mut conn)
-            .await
-            .unwrap();
-        assert_eq!(rows, 1, "a seal-key re-key must not append a root key row");
-
-        // Fetch each nonce by its own id, rather than `eq_any` (whose row order is
-        // unspecified), and assert the counter strictly advanced. A weaker `assert_ne!` would
-        // still pass if the counter reset, as long as the two nonces happened to differ.
-        let before_nonce: Vec<u8> = schema::aead_encrypted::table
-            .find(before)
-            .select(schema::aead_encrypted::current_nonce)
-            .first(&mut conn)
-            .await
-            .unwrap();
-        let after_nonce: Vec<u8> = schema::aead_encrypted::table
-            .find(after)
-            .select(schema::aead_encrypted::current_nonce)
-            .first(&mut conn)
-            .await
-            .unwrap();
-        assert!(
-            after_nonce > before_nonce,
-            "nonce counter must keep advancing across a rekey, not reset"
-        );
-    }
-
-    #[tokio::test]
-    #[test_log::test]
-    async fn rekey_invalidates_the_old_seal_key() {
-        let db = db::create_test_pool().await;
-        let mut actor = bootstrapped_actor(&db).await;
-
-        actor.rekey_root_key(KeyCell::from([7u8; 32])).await.unwrap();
-        actor.seal().await.unwrap();
-
-        // A no-op rekey would leave the old seal key working; it must not.
-        let err = actor
-            .try_unseal(KeyCell::from([0u8; 32]))
-            .await
-            .unwrap_err();
-        assert!(
-            matches!(err, Error::InvalidKey),
-            "old seal key must no longer unseal after a rekey, got {err:?}"
-        );
-
-        // A failed unseal must leave the sealed state intact: the new seal key must still be
-        // able to unseal on the next attempt.
-        actor.try_unseal(KeyCell::from([7u8; 32])).await.unwrap();
-    }
-
-    #[tokio::test]
-    #[test_log::test]
-    async fn integrity_envelopes_survive_a_rekey() {
-        let db = db::create_test_pool().await;
-        let mut actor = bootstrapped_actor(&db).await;
-
-        let mac_input = b"operator_credentials/1".to_vec();
-        let (key_version, mac) = actor.sign_integrity(mac_input.clone()).unwrap();
-
-        actor.rekey_root_key(KeyCell::from([9u8; 32])).await.unwrap();
-
-        assert!(
-            actor
-                .verify_integrity(mac_input, mac, key_version)
-                .unwrap(),
-            "a seal-key re-key must not invalidate existing attestations"
-        );
-    }
-}

server/crates/arbiter-server/src/actors/vault_coordinator/mod.rs

@@ -1,923 +0,0 @@
-use std::collections::HashMap;
-
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-use diesel::{ExpressionMethods as _, QueryDsl};
-use diesel_async::RunQueryDsl;
-use kameo::{Actor, actor::ActorRef, messages, prelude::Message};
-use rand_core::{OsRng, RngCore as _};
-use tracing::error;
-
-use crate::{
-    actors::{
-        proposal_manager::events::ProposalApproved,
-        vault::{Bootstrap, RekeyRootKey, TryUnseal, Vault},
-    },
-    crypto::{KeyCell, derive_key, encryption::v1::Nonce, shamir, shamir::shamir_threshold},
-    db::{
-        self, models,
-        proposal::{ProposalKind, replace_operator},
-        schema,
-    },
-};
-
-#[derive(Debug, thiserror::Error)]
-pub enum Error {
-    #[error("Already coordinating a bootstrap")]
-    AlreadyBootstrapping,
-    #[error("Already coordinating an unseal")]
-    AlreadyUnsealing,
-    #[error("Rekey not in progress")]
-    NotRekeying,
-    #[error("Bootstrap not in progress")]
-    NotBootstrapping,
-    #[error("Unseal not in progress")]
-    NotUnsealing,
-    #[error("Operator already contributed")]
-    DuplicateContribution,
-    #[error("Operator not found in database")]
-    OperatorNotFound,
-    #[error("Invalid passphrase (decryption failed)")]
-    InvalidPassphrase,
-    #[error("Shamir error: {0}")]
-    Shamir(String),
-    #[error("Database connection error: {0}")]
-    DatabaseConnection(#[from] db::PoolError),
-    #[error("Database query error: {0}")]
-    DatabaseQuery(#[from] diesel::result::Error),
-    #[error("Encryption error")]
-    Encryption,
-    #[error("Vault error")]
-    VaultError,
-    #[error("Two-operator vaults require at least one recovery share")]
-    TwoOperatorsRequireRecovery,
-    #[error("Broken database")]
-    BrokenDatabase,
-    #[error("A committee must have at least one ordinary operator")]
-    EmptyCommittee,
-    #[error("Recovery operators are sleeping")]
-    RecoveryNotActive,
-}
-
-// Passphrases stored as plain Vec<u8> (not SafeCell) so CoordinatorState is Sync.
-// They are ephemeral and dropped immediately after use.
-enum CoordinatorState {
-    Idle,
-    Bootstrapping {
-        declared_count: usize,
-        recovery_count: usize,
-        passphrases: HashMap<i32, Vec<u8>>,
-        recovery_passphrases: HashMap<i32, Vec<u8>>,
-    },
-    Unsealing {
-        threshold: usize,
-        ordinary_passphrases: HashMap<i32, Vec<u8>>,
-        recovery_passphrases: HashMap<i32, Vec<u8>>,
-    },
-    /// Shamir re-key after `replace_operator` or `trigger_rekey` is approved (§3.3).
-    /// Collects new passphrases from all current operators, then generates a fresh seal key,
-    /// re-splits it, and re-encrypts the vault root key.
-    Rekeying {
-        ordinary_count: usize,
-        recovery_count: usize,
-        passphrases: HashMap<i32, Vec<u8>>,
-        recovery_passphrases: HashMap<i32, Vec<u8>>,
-    },
-}
-
-#[derive(Actor)]
-pub struct VaultCoordinator {
-    db: db::DatabasePool,
-    vault: ActorRef<Vault>,
-    state: CoordinatorState,
-}
-
-impl VaultCoordinator {
-    pub const fn new(db: db::DatabasePool, vault: ActorRef<Vault>) -> Self {
-        Self {
-            db,
-            vault,
-            state: CoordinatorState::Idle,
-        }
-    }
-}
-
-const SHARE_AAD: &[u8] = b"arbiter/shamir-share/v1";
-
-fn encrypt_share(
-    passphrase_bytes: Vec<u8>,
-    share: &[u8],
-) -> Result<(Vec<u8>, Vec<u8>, Vec<u8>), Error> {
-    let mut share_salt = vec![0u8; 32];
-    OsRng.fill_bytes(&mut share_salt);
-
-    let mut passphrase_cell = SafeCell::new(passphrase_bytes);
-    let mut share_seal_key = derive_key(&mut passphrase_cell, &share_salt);
-
-    let nonce = Nonce::default();
-    let encrypted_share = share_seal_key
-        .encrypt(&nonce, SHARE_AAD, share)
-        .map_err(|_| Error::Encryption)?;
-
-    Ok((encrypted_share, nonce.to_vec(), share_salt))
-}
-
-fn decrypt_share(
-    passphrase_bytes: Vec<u8>,
-    encrypted_share: Vec<u8>,
-    share_nonce_bytes: &[u8],
-    share_salt: &[u8],
-    operator_id: i32,
-) -> Result<Vec<u8>, Error> {
-    let nonce = Nonce::try_from(share_nonce_bytes).map_err(|()| {
-        error!(operator_id, "Invalid nonce in DB");
-        Error::BrokenDatabase
-    })?;
-
-    let mut passphrase_cell = SafeCell::new(passphrase_bytes);
-    let mut share_seal_key = derive_key(&mut passphrase_cell, share_salt);
-
-    let mut share_buffer = SafeCell::new(encrypted_share);
-    share_seal_key
-        .decrypt_in_place(&nonce, SHARE_AAD, &mut share_buffer)
-        .map_err(|_| Error::InvalidPassphrase)?;
-
-    Ok(share_buffer.read().clone())
-}
-
-/// Records the threshold of the split that produced the stored shares.
-async fn store_threshold(conn: &mut db::DatabaseConnection, threshold: usize) -> Result<(), Error> {
-    // A threshold that doesn't fit in the column is a bug, not a real empty-committee refusal.
-    let threshold = i32::try_from(threshold).map_err(|_| Error::BrokenDatabase)?;
-    let rows_updated = diesel::update(schema::arbiter_settings::table)
-        .set(schema::arbiter_settings::shamir_threshold.eq(Some(threshold)))
-        .execute(conn)
-        .await?;
-    // The singleton row always exists (up.sql seeds it), so anything else means the update did
-    // not land -- bootstrap would then report success while the threshold stays NULL forever.
-    if rows_updated != 1 {
-        return Err(Error::BrokenDatabase);
-    }
-    Ok(())
-}
-
-/// Reads back the threshold recorded at bootstrap or re-key time.
-async fn load_threshold(conn: &mut db::DatabaseConnection) -> Result<usize, Error> {
-    let stored: Option<i32> = schema::arbiter_settings::table
-        .select(schema::arbiter_settings::shamir_threshold)
-        .first(conn)
-        .await?;
-
-    // A missing or out-of-range value here means the recorded threshold is corrupt, not that the
-    // committee is genuinely empty -- `EmptyCommittee` is reserved for the real domain refusal.
-    stored
-        .and_then(|threshold| usize::try_from(threshold).ok())
-        .ok_or(Error::BrokenDatabase)
-}
-
-/// §3.4: Split the seal key across ordinary + recovery operators.
-/// Threshold = `shamir_threshold(ordinary_count)`; total shares = ordinary + recovery.
-/// When `ordinary_count` == 1 (threshold = 1), vsss-rs does not support a proper split,
-/// so each share is the seal key itself — any single participant can reconstruct.
-async fn finalize_bootstrap(
-    db: db::DatabasePool,
-    vault: ActorRef<Vault>,
-    ordinary_passphrases: HashMap<i32, Vec<u8>>,
-    recovery_passphrases: HashMap<i32, Vec<u8>>,
-) -> Result<(), Error> {
-    let ordinary_count = ordinary_passphrases.len();
-    let recovery_count = recovery_passphrases.len();
-    let total = ordinary_count + recovery_count;
-    let threshold = shamir_threshold(ordinary_count).ok_or(Error::EmptyCommittee)?;
-
-    let mut seal_key_bytes = [0u8; 32];
-    OsRng.fill_bytes(&mut seal_key_bytes);
-
-    // threshold == 1 means any single share reconstructs the key (degenerate split).
-    // vsss-rs requires threshold >= 2, so we store the key directly in this case.
-    let shares: Vec<Vec<u8>> = if threshold >= 2 {
-        shamir::split_key(threshold, total, &seal_key_bytes, OsRng)
-            .map_err(|e| Error::Shamir(e.to_string()))?
-    } else {
-        std::iter::repeat_with(|| seal_key_bytes.to_vec()).take(total).collect()
-    };
-
-    let seal_key = KeyCell::from(seal_key_bytes);
-
-    let mut conn = db.get().await?;
-    let mut shares_iter = shares.into_iter();
-
-    for (operator_id_raw, passphrase_bytes) in ordinary_passphrases {
-        let share = shares_iter
-            .next()
-            .expect("split_key returned enough shares");
-        let (encrypted_share, nonce_bytes, share_salt) = encrypt_share(passphrase_bytes, &share)?;
-
-        diesel::replace_into(schema::operator::table)
-            .values((
-                schema::operator::id.eq(Some(operator_id_raw)),
-                schema::operator::share.eq(&encrypted_share),
-                schema::operator::share_nonce.eq(&nonce_bytes),
-                schema::operator::share_salt.eq(&share_salt),
-                schema::operator::created_at.eq(models::SqliteTimestamp::now()),
-                schema::operator::updated_at.eq(models::SqliteTimestamp::now()),
-            ))
-            .execute(&mut conn)
-            .await?;
-    }
-
-    for (recovery_id_raw, passphrase_bytes) in recovery_passphrases {
-        let share = shares_iter
-            .next()
-            .expect("split_key returned enough shares");
-        let (encrypted_share, nonce_bytes, share_salt) = encrypt_share(passphrase_bytes, &share)?;
-
-        diesel::replace_into(schema::recovery_operator::table)
-            .values((
-                schema::recovery_operator::id.eq(recovery_id_raw),
-                schema::recovery_operator::share.eq(&encrypted_share),
-                schema::recovery_operator::share_nonce.eq(&nonce_bytes),
-                schema::recovery_operator::share_salt.eq(&share_salt),
-                schema::recovery_operator::created_at.eq(models::SqliteTimestamp::now()),
-                schema::recovery_operator::updated_at.eq(models::SqliteTimestamp::now()),
-            ))
-            .execute(&mut conn)
-            .await?;
-    }
-
-    store_threshold(&mut conn, threshold).await?;
-
-    vault.ask(Bootstrap { seal_key }).await.map_err(|err| {
-        error!(?err, "Vault bootstrap failed");
-        Error::VaultError
-    })?;
-
-    Ok(())
-}
-
-/// §3.5: Unseal using any threshold-sized mix of ordinary + recovery shares.
-async fn finalize_unseal(
-    db: db::DatabasePool,
-    vault: ActorRef<Vault>,
-    ordinary_passphrases: HashMap<i32, Vec<u8>>,
-    recovery_passphrases: HashMap<i32, Vec<u8>>,
-) -> Result<(), Error> {
-    let mut conn = db.get().await?;
-
-    // Determine whether shares were stored as raw keys (threshold=1) or vsss-rs splits (threshold>=2).
-    let threshold = load_threshold(&mut conn).await?;
-
-    let mut shares: Vec<Vec<u8>> = Vec::new();
-
-    for (operator_id_raw, passphrase_bytes) in ordinary_passphrases {
-        let (encrypted_share, share_nonce_bytes, share_salt): (Vec<u8>, Vec<u8>, Vec<u8>) =
-            schema::operator::table
-                .filter(schema::operator::id.eq(Some(operator_id_raw)))
-                .select((
-                    schema::operator::share,
-                    schema::operator::share_nonce,
-                    schema::operator::share_salt,
-                ))
-                .first(&mut conn)
-                .await
-                .map_err(|_| Error::OperatorNotFound)?;
-
-        shares.push(decrypt_share(
-            passphrase_bytes,
-            encrypted_share,
-            &share_nonce_bytes,
-            &share_salt,
-            operator_id_raw,
-        )?);
-    }
-
-    for (recovery_id_raw, passphrase_bytes) in recovery_passphrases {
-        let (encrypted_share, share_nonce_bytes, share_salt): (Vec<u8>, Vec<u8>, Vec<u8>) =
-            schema::recovery_operator::table
-                .find(recovery_id_raw)
-                .select((
-                    schema::recovery_operator::share,
-                    schema::recovery_operator::share_nonce,
-                    schema::recovery_operator::share_salt,
-                ))
-                .first(&mut conn)
-                .await
-                .map_err(|_| Error::OperatorNotFound)?;
-
-        shares.push(decrypt_share(
-            passphrase_bytes,
-            encrypted_share,
-            &share_nonce_bytes,
-            &share_salt,
-            recovery_id_raw,
-        )?);
-    }
-
-    // When threshold==1, shares are raw 32-byte seal keys (vsss-rs cannot split 1-of-N).
-    // Any single decrypted share is the key itself.
-    let seal_key_bytes: [u8; 32] = if threshold <= 1 {
-        let raw = shares
-            .into_iter()
-            .next()
-            .ok_or_else(|| Error::Shamir("No shares available".into()))?;
-        raw.try_into()
-            .map_err(|_| Error::Shamir("Invalid share length".into()))?
-    } else {
-        shamir::combine_shares(&shares).map_err(|e| Error::Shamir(e.to_string()))?
-    };
-
-    let seal_key = KeyCell::from(seal_key_bytes);
-
-    vault.ask(TryUnseal { seal_key }).await.map_err(|err| {
-        error!(?err, "Vault unseal failed");
-        Error::VaultError
-    })?;
-
-    Ok(())
-}
-
-/// §3.3: Generate a fresh seal key, split across current operators, re-encrypt the vault root key.
-/// Called after `replace_operator` or `trigger_rekey` is approved and all contributors submit.
-async fn finalize_rekey(
-    db: db::DatabasePool,
-    vault: ActorRef<Vault>,
-    ordinary_passphrases: HashMap<i32, Vec<u8>>,
-    recovery_passphrases: HashMap<i32, Vec<u8>>,
-) -> Result<(), Error> {
-    let ordinary_count = ordinary_passphrases.len();
-    let recovery_count = recovery_passphrases.len();
-    let total = ordinary_count + recovery_count;
-    let threshold = shamir_threshold(ordinary_count).ok_or(Error::EmptyCommittee)?;
-
-    let mut new_seal_key_bytes = [0u8; 32];
-    OsRng.fill_bytes(&mut new_seal_key_bytes);
-
-    let shares: Vec<Vec<u8>> = if threshold >= 2 {
-        shamir::split_key(threshold, total, &new_seal_key_bytes, OsRng)
-            .map_err(|e| Error::Shamir(e.to_string()))?
-    } else {
-        std::iter::repeat_with(|| new_seal_key_bytes.to_vec())
-            .take(total)
-            .collect()
-    };
-
-    let mut conn = db.get().await?;
-    let mut shares_iter = shares.into_iter();
-
-    for (operator_id_raw, passphrase_bytes) in ordinary_passphrases {
-        let share = shares_iter
-            .next()
-            .expect("split_key returned enough shares");
-        let (encrypted_share, nonce_bytes, share_salt) = encrypt_share(passphrase_bytes, &share)?;
-
-        diesel::replace_into(schema::operator::table)
-            .values((
-                schema::operator::id.eq(Some(operator_id_raw)),
-                schema::operator::share.eq(&encrypted_share),
-                schema::operator::share_nonce.eq(&nonce_bytes),
-                schema::operator::share_salt.eq(&share_salt),
-                schema::operator::created_at.eq(models::SqliteTimestamp::now()),
-                schema::operator::updated_at.eq(models::SqliteTimestamp::now()),
-            ))
-            .execute(&mut conn)
-            .await?;
-    }
-
-    for (recovery_id_raw, passphrase_bytes) in recovery_passphrases {
-        let share = shares_iter
-            .next()
-            .expect("split_key returned enough shares");
-        let (encrypted_share, nonce_bytes, share_salt) = encrypt_share(passphrase_bytes, &share)?;
-
-        diesel::replace_into(schema::recovery_operator::table)
-            .values((
-                schema::recovery_operator::id.eq(recovery_id_raw),
-                schema::recovery_operator::share.eq(&encrypted_share),
-                schema::recovery_operator::share_nonce.eq(&nonce_bytes),
-                schema::recovery_operator::share_salt.eq(&share_salt),
-                schema::recovery_operator::created_at.eq(models::SqliteTimestamp::now()),
-                schema::recovery_operator::updated_at.eq(models::SqliteTimestamp::now()),
-            ))
-            .execute(&mut conn)
-            .await?;
-    }
-
-    store_threshold(&mut conn, threshold).await?;
-
-    drop(conn);
-
-    let new_seal_key = KeyCell::from(new_seal_key_bytes);
-    vault
-        .ask(RekeyRootKey { new_seal_key })
-        .await
-        .map_err(|err| {
-            error!(?err, "Vault rekey failed");
-            Error::VaultError
-        })?;
-
-    Ok(())
-}
-
-#[messages]
-impl VaultCoordinator {
-    /// Phase 1 of multi-operator bootstrap: declare the committee size.
-    #[message]
-    #[expect(clippy::unused_async, reason = "kameo requires messages to be async")]
-    pub async fn start_bootstrap(
-        &mut self,
-        operator_id: i32,
-        declared_count: usize,
-        recovery_count: usize,
-    ) -> Result<(), Error> {
-        let _ = operator_id; // fixme!: any authenticated operator may announce the committee size. the first call wins
-        if !matches!(self.state, CoordinatorState::Idle) {
-            return Err(Error::AlreadyBootstrapping);
-        }
-        if declared_count == 0 {
-            return Err(Error::EmptyCommittee);
-        }
-        if declared_count == 2 && recovery_count == 0 {
-            return Err(Error::TwoOperatorsRequireRecovery);
-        }
-        self.state = CoordinatorState::Bootstrapping {
-            declared_count,
-            recovery_count,
-            passphrases: HashMap::new(),
-            recovery_passphrases: HashMap::new(),
-        };
-        Ok(())
-    }
-
-    /// Phase 2 of multi-operator bootstrap: ordinary operator contributes a passphrase.
-    /// Returns Ok(true) when all ordinary + recovery operators contributed and bootstrap finalized.
-    #[message]
-    pub async fn contribute_bootstrap(
-        &mut self,
-        operator_id: i32,
-        mut passphrase: SafeCell<Vec<u8>>,
-    ) -> Result<bool, Error> {
-        let CoordinatorState::Bootstrapping {
-            declared_count,
-            recovery_count,
-            passphrases,
-            recovery_passphrases,
-        } = &mut self.state
-        else {
-            return Err(Error::NotBootstrapping);
-        };
-
-        if passphrases.contains_key(&operator_id) {
-            return Err(Error::DuplicateContribution);
-        }
-
-        let passphrase_bytes = passphrase.read().to_vec();
-        passphrases.insert(operator_id, passphrase_bytes);
-
-        if passphrases.len() < *declared_count || recovery_passphrases.len() < *recovery_count {
-            return Ok(false);
-        }
-
-        let CoordinatorState::Bootstrapping {
-            passphrases,
-            recovery_passphrases,
-            ..
-        } = std::mem::replace(&mut self.state, CoordinatorState::Idle)
-        else {
-            unreachable!()
-        };
-
-        finalize_bootstrap(
-            self.db.clone(),
-            self.vault.clone(),
-            passphrases,
-            recovery_passphrases,
-        )
-        .await?;
-        Ok(true)
-    }
-
-    /// Phase 2 of multi-operator bootstrap: recovery operator contributes a passphrase.
-    /// Returns Ok(true) when all contributors are in and bootstrap finalized.
-    #[message]
-    pub async fn contribute_recovery_bootstrap(
-        &mut self,
-        recovery_operator_id: i32,
-        mut passphrase: SafeCell<Vec<u8>>,
-    ) -> Result<bool, Error> {
-        let CoordinatorState::Bootstrapping {
-            declared_count,
-            recovery_count,
-            passphrases,
-            recovery_passphrases,
-        } = &mut self.state
-        else {
-            return Err(Error::NotBootstrapping);
-        };
-
-        if recovery_passphrases.contains_key(&recovery_operator_id) {
-            return Err(Error::DuplicateContribution);
-        }
-
-        let passphrase_bytes = passphrase.read().to_vec();
-        recovery_passphrases.insert(recovery_operator_id, passphrase_bytes);
-
-        if passphrases.len() < *declared_count || recovery_passphrases.len() < *recovery_count {
-            return Ok(false);
-        }
-
-        let CoordinatorState::Bootstrapping {
-            passphrases,
-            recovery_passphrases,
-            ..
-        } = std::mem::replace(&mut self.state, CoordinatorState::Idle)
-        else {
-            unreachable!()
-        };
-
-        finalize_bootstrap(
-            self.db.clone(),
-            self.vault.clone(),
-            passphrases,
-            recovery_passphrases,
-        )
-        .await?;
-        Ok(true)
-    }
-
-    /// Contribute a passphrase for vault unseal (ordinary operator).
-    /// Returns Ok(true) when threshold reached and vault is unsealed.
-    #[message]
-    pub async fn contribute_unseal(
-        &mut self,
-        operator_id: i32,
-        mut passphrase: SafeCell<Vec<u8>>,
-    ) -> Result<bool, Error> {
-        self.ensure_unsealing_state().await?;
-
-        let CoordinatorState::Unsealing {
-            threshold,
-            ordinary_passphrases,
-            recovery_passphrases,
-        } = &mut self.state
-        else {
-            return Err(Error::NotUnsealing);
-        };
-
-        if ordinary_passphrases.contains_key(&operator_id) {
-            return Err(Error::DuplicateContribution);
-        }
-
-        let passphrase_bytes = passphrase.read().to_vec();
-        ordinary_passphrases.insert(operator_id, passphrase_bytes);
-
-        if ordinary_passphrases.len() + recovery_passphrases.len() < *threshold {
-            return Ok(false);
-        }
-
-        self.do_finalize_unseal().await
-    }
-
-    /// Contribute a passphrase for vault unseal (recovery operator, §3.5).
-    /// Recovery operators may contribute during unseal when recovery is active.
-    /// Returns Ok(true) when threshold reached and vault is unsealed.
-    #[message]
-    pub async fn contribute_recovery_unseal(
-        &mut self,
-        recovery_operator_id: i32,
-        mut passphrase: SafeCell<Vec<u8>>,
-    ) -> Result<bool, Error> {
-        {
-            let mut conn = self.db.get().await?;
-            if !db::recovery::is_active(&mut conn).await? {
-                return Err(Error::RecoveryNotActive);
-            }
-        }
-
-        self.ensure_unsealing_state().await?;
-
-        let CoordinatorState::Unsealing {
-            threshold,
-            ordinary_passphrases,
-            recovery_passphrases,
-        } = &mut self.state
-        else {
-            return Err(Error::NotUnsealing);
-        };
-
-        if recovery_passphrases.contains_key(&recovery_operator_id) {
-            return Err(Error::DuplicateContribution);
-        }
-
-        let passphrase_bytes = passphrase.read().to_vec();
-        recovery_passphrases.insert(recovery_operator_id, passphrase_bytes);
-
-        if ordinary_passphrases.len() + recovery_passphrases.len() < *threshold {
-            return Ok(false);
-        }
-
-        self.do_finalize_unseal().await
-    }
-}
-
-impl VaultCoordinator {
-    /// Initializes `CoordinatorState::Unsealing` on first call if still `Idle`.
-    /// Threshold comes from the recorded split parameters (§3.4), not from a live row count.
-    async fn ensure_unsealing_state(&mut self) -> Result<(), Error> {
-        if matches!(self.state, CoordinatorState::Idle) {
-            let mut conn = self.db.get().await?;
-            let threshold = load_threshold(&mut conn).await?;
-            drop(conn);
-            self.state = CoordinatorState::Unsealing {
-                threshold,
-                ordinary_passphrases: HashMap::new(),
-                recovery_passphrases: HashMap::new(),
-            };
-        }
-        Ok(())
-    }
-
-    /// Moves state back to Idle and calls finalize_unseal.
-    async fn do_finalize_unseal(&mut self) -> Result<bool, Error> {
-        let CoordinatorState::Unsealing {
-            ordinary_passphrases,
-            recovery_passphrases,
-            ..
-        } = std::mem::replace(&mut self.state, CoordinatorState::Idle)
-        else {
-            unreachable!()
-        };
-
-        finalize_unseal(
-            self.db.clone(),
-            self.vault.clone(),
-            ordinary_passphrases,
-            recovery_passphrases,
-        )
-        .await?;
-        Ok(true)
-    }
-
-    async fn do_finalize_rekey(&mut self) -> Result<bool, Error> {
-        let CoordinatorState::Rekeying {
-            passphrases,
-            recovery_passphrases,
-            ..
-        } = std::mem::replace(&mut self.state, CoordinatorState::Idle)
-        else {
-            unreachable!()
-        };
-
-        finalize_rekey(
-            self.db.clone(),
-            self.vault.clone(),
-            passphrases,
-            recovery_passphrases,
-        )
-        .await?;
-        Ok(true)
-    }
-}
-
-#[messages]
-impl VaultCoordinator {
-    /// Begin Shamir re-key after a key-rotation proposal is approved (§3.3).
-    /// Queries the current operator and recovery operator counts from the DB,
-    /// then transitions to Rekeying state awaiting contributions from all of them.
-    #[message]
-    pub async fn start_rekey(&mut self) -> Result<(), Error> {
-        self.ensure_idle()?;
-        let mut conn = self.db.get().await?;
-        let ordinary_count: i64 = schema::operator_identity::table
-            .count()
-            .get_result(&mut conn)
-            .await?;
-        let recovery_count: i64 = schema::recovery_operator_identity::table
-            .count()
-            .get_result(&mut conn)
-            .await?;
-        self.state = CoordinatorState::Rekeying {
-            ordinary_count: ordinary_count as usize,
-            recovery_count: recovery_count as usize,
-            passphrases: HashMap::new(),
-            recovery_passphrases: HashMap::new(),
-        };
-        Ok(())
-    }
-
-    /// Contribute an ordinary operator passphrase for the re-key.
-    /// Returns Ok(true) when all contributors have submitted and the re-key is complete.
-    #[message]
-    pub async fn contribute_rekey(
-        &mut self,
-        operator_id: i32,
-        mut passphrase: SafeCell<Vec<u8>>,
-    ) -> Result<bool, Error> {
-        let CoordinatorState::Rekeying {
-            ordinary_count,
-            recovery_count,
-            passphrases,
-            recovery_passphrases,
-        } = &mut self.state
-        else {
-            return Err(Error::NotRekeying);
-        };
-
-        if passphrases.contains_key(&operator_id) {
-            return Err(Error::DuplicateContribution);
-        }
-
-        passphrases.insert(operator_id, passphrase.read().to_vec());
-
-        if passphrases.len() < *ordinary_count || recovery_passphrases.len() < *recovery_count {
-            return Ok(false);
-        }
-
-        self.do_finalize_rekey().await
-    }
-
-    /// Contribute a recovery operator passphrase for the re-key.
-    /// Returns Ok(true) when all contributors have submitted and the re-key is complete.
-    #[message]
-    pub async fn contribute_recovery_rekey(
-        &mut self,
-        recovery_operator_id: i32,
-        mut passphrase: SafeCell<Vec<u8>>,
-    ) -> Result<bool, Error> {
-        let CoordinatorState::Rekeying {
-            ordinary_count,
-            recovery_count,
-            passphrases,
-            recovery_passphrases,
-        } = &mut self.state
-        else {
-            return Err(Error::NotRekeying);
-        };
-
-        if recovery_passphrases.contains_key(&recovery_operator_id) {
-            return Err(Error::DuplicateContribution);
-        }
-
-        recovery_passphrases.insert(recovery_operator_id, passphrase.read().to_vec());
-
-        if passphrases.len() < *ordinary_count || recovery_passphrases.len() < *recovery_count {
-            return Ok(false);
-        }
-
-        self.do_finalize_rekey().await
-    }
-}
-
-impl Message<ProposalApproved> for VaultCoordinator {
-    type Reply = ();
-
-    /// Every subscriber sees every approval and acts only on the kinds it owns.
-    async fn handle(
-        &mut self,
-        msg: ProposalApproved,
-        _ctx: &mut kameo::prelude::Context<Self, Self::Reply>,
-    ) -> Self::Reply {
-        let result = match msg.kind {
-            ProposalKind::ReplaceOperator(settings) => self.replace_operator(&settings).await,
-            ProposalKind::TriggerRekey => self.start_rekey().await,
-            _ => return,
-        };
-
-        if let Err(error) = result {
-            error!(
-                ?error,
-                proposal_id = msg.id.to_raw(),
-                "Failed to execute an approved proposal"
-            );
-        }
-    }
-}
-
-impl VaultCoordinator {
-    /// The coordinator runs one ceremony at a time; anything that starts a new one has to say
-    /// so before it changes any state the ceremony depends on.
-    const fn ensure_idle(&self) -> Result<(), Error> {
-        if matches!(self.state, CoordinatorState::Idle) {
-            Ok(())
-        } else {
-            Err(Error::AlreadyBootstrapping)
-        }
-    }
-
-    /// Replaces the operator's public key in place, keeping their id and history, drops the
-    /// share that key no longer matches, then begins a coordinated re-key (§3.3).
-    async fn replace_operator(
-        &mut self,
-        settings: &replace_operator::Settings,
-    ) -> Result<(), Error> {
-        // Checked before anything is written. The re-key is what gives the replaced operator
-        // a share they can use; if the coordinator is mid-ceremony, `start_rekey` refuses, and
-        // swapping the key and destroying the share first would leave that operator locked
-        // out with no re-key running and nothing to undo it -- the caller only logs the error.
-        self.ensure_idle()?;
-
-        let mut conn = self.db.get().await?;
-
-        diesel::update(schema::operator_identity::table)
-            .filter(schema::operator_identity::id.eq(settings.old_operator_id))
-            .set(schema::operator_identity::public_key.eq(&settings.new_pubkey))
-            .execute(&mut conn)
-            .await?;
-
-        // Drop the stale Shamir share; finalize_rekey stores a fresh one.
-        diesel::delete(schema::operator::table)
-            .filter(schema::operator::id.eq(Some(settings.old_operator_id)))
-            .execute(&mut conn)
-            .await?;
-
-        drop(conn);
-
-        self.start_rekey().await
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::{CoordinatorState, Error, VaultCoordinator};
-    use crate::{
-        actors::{GlobalActors, vault::Vault},
-        db::{self, models::OperatorIdentityId, proposal::replace_operator, schema},
-    };
-
-    use diesel::{ExpressionMethods as _, QueryDsl as _, dsl::insert_into};
-    use diesel_async::RunQueryDsl;
-    use kameo::actor::Spawn as _;
-    use std::collections::HashMap;
-
-    /// An approved `ReplaceOperator` that arrives while another ceremony is running must
-    /// change nothing. Swapping the public key and deleting the share are only safe because a
-    /// re-key follows and hands the operator a share for the new key; when `start_rekey`
-    /// refuses, the operator would otherwise be left holding a key with no share, and the
-    /// caller does nothing with the error but log it.
-    #[tokio::test]
-    async fn a_refused_rekey_leaves_the_operator_untouched() {
-        let pool = db::create_test_pool().await;
-        let mut conn = pool.get().await.unwrap();
-
-        let old_key = rand::random::<[u8; 32]>().to_vec();
-        let operator_id: OperatorIdentityId = insert_into(schema::operator_identity::table)
-            .values(schema::operator_identity::public_key.eq(&old_key))
-            .returning(schema::operator_identity::id)
-            .get_result(&mut conn)
-            .await
-            .unwrap();
-        insert_into(schema::operator::table)
-            .values((
-                schema::operator::id.eq(Some(operator_id)),
-                schema::operator::share.eq(vec![1u8; 32]),
-                schema::operator::share_nonce.eq(vec![2u8; 24]),
-                schema::operator::share_salt.eq(vec![3u8; 32]),
-            ))
-            .execute(&mut conn)
-            .await
-            .unwrap();
-        drop(conn);
-
-        let vault = Vault::spawn(
-            Vault::new(pool.clone(), GlobalActors::spawn_message_bus())
-                .await
-                .unwrap(),
-        );
-        let mut coordinator = VaultCoordinator::new(pool.clone(), vault);
-        coordinator.state = CoordinatorState::Rekeying {
-            ordinary_count: 2,
-            recovery_count: 0,
-            passphrases: HashMap::new(),
-            recovery_passphrases: HashMap::new(),
-        };
-
-        let result = coordinator
-            .replace_operator(&replace_operator::Settings {
-                old_operator_id: operator_id,
-                new_pubkey: vec![9u8; 32],
-            })
-            .await;
-        assert!(
-            matches!(result, Err(Error::AlreadyBootstrapping)),
-            "a busy coordinator must refuse the replacement, got {result:?}"
-        );
-
-        let mut conn = pool.get().await.unwrap();
-        let stored_key: Vec<u8> = schema::operator_identity::table
-            .find(operator_id)
-            .select(schema::operator_identity::public_key)
-            .first(&mut conn)
-            .await
-            .unwrap();
-        assert_eq!(
-            stored_key, old_key,
-            "the public key must not be swapped when no re-key can follow"
-        );
-
-        let shares: i64 = schema::operator::table
-            .filter(schema::operator::id.eq(Some(operator_id)))
-            .count()
-            .get_result(&mut conn)
-            .await
-            .unwrap();
-        assert_eq!(shares, 1, "the operator's share must not be destroyed");
-    }
-}

server/crates/arbiter-server/src/context/mod.rs

@@ -1,45 +1,53 @@
+use std::sync::Arc;
+
+use miette::Diagnostic;
+use thiserror::Error;
+
 use crate::{
     actors::GlobalActors,
     context::tls::TlsManager,
     db::{self},
 };
 
-use std::sync::Arc;
-use thiserror::Error;
-
 pub mod tls;
 
-#[derive(Error, Debug)]
+#[derive(Error, Debug, Diagnostic)]
 pub enum InitError {
     #[error("Database setup failed: {0}")]
+    #[diagnostic(code(arbiter_server::init::database_setup))]
     DatabaseSetup(#[from] db::DatabaseSetupError),
 
     #[error("Connection acquire failed: {0}")]
+    #[diagnostic(code(arbiter_server::init::database_pool))]
     DatabasePool(#[from] db::PoolError),
 
     #[error("Database query error: {0}")]
+    #[diagnostic(code(arbiter_server::init::database_query))]
     DatabaseQuery(#[from] diesel::result::Error),
 
     #[error("TLS initialization failed: {0}")]
+    #[diagnostic(code(arbiter_server::init::tls_init))]
     Tls(#[from] tls::InitError),
 
     #[error("Actor spawn failed: {0}")]
+    #[diagnostic(code(arbiter_server::init::actor_spawn))]
     ActorSpawn(#[from] crate::actors::SpawnError),
 
     #[error("I/O Error: {0}")]
+    #[diagnostic(code(arbiter_server::init::io))]
     Io(#[from] std::io::Error),
 }
 
-pub struct __ServerContextInner {
+pub struct _ServerContextInner {
     pub db: db::DatabasePool,
     pub tls: TlsManager,
     pub actors: GlobalActors,
 }
 #[derive(Clone)]
-pub struct ServerContext(Arc<__ServerContextInner>);
+pub struct ServerContext(Arc<_ServerContextInner>);
 
 impl std::ops::Deref for ServerContext {
-    type Target = __ServerContextInner;
+    type Target = _ServerContextInner;
 
     fn deref(&self) -> &Self::Target {
         &self.0
@@ -48,7 +56,7 @@ impl std::ops::Deref for ServerContext {
 
 impl ServerContext {
     pub async fn new(db: db::DatabasePool) -> Result<Self, InitError> {
-        Ok(Self(Arc::new(__ServerContextInner {
+        Ok(Self(Arc::new(_ServerContextInner {
             actors: GlobalActors::spawn(db.clone()).await?,
             tls: TlsManager::new(db.clone()).await?,
             db,

server/crates/arbiter-server/src/context/tls.rs

@@ -1,3 +1,17 @@
+use std::string::FromUtf8Error;
+
+use diesel::{ExpressionMethods as _, QueryDsl, SelectableHelper as _};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use miette::Diagnostic;
+use pem::Pem;
+use rcgen::{
+    BasicConstraints, Certificate, CertificateParams, CertifiedIssuer, DistinguishedName, DnType,
+    IsCa, Issuer, KeyPair, KeyUsagePurpose,
+};
+use rustls::pki_types::pem::PemObject;
+use thiserror::Error;
+use tonic::transport::CertificateDer;
+
 use crate::db::{
     self,
     models::{NewTlsHistory, TlsHistory},
@@ -7,58 +21,48 @@ use crate::db::{
     },
 };
 
-use diesel::{ExpressionMethods as _, QueryDsl, SelectableHelper as _};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use pem::Pem;
-use rcgen::{
-    BasicConstraints, Certificate, CertificateParams, CertifiedIssuer, DistinguishedName, DnType,
-    IsCa, Issuer, KeyPair, KeyUsagePurpose, SanType,
-};
-use rustls::pki_types::pem::PemObject;
-use std::{net::Ipv4Addr, string::FromUtf8Error};
-use thiserror::Error;
-use tonic::transport::CertificateDer;
-
 const ENCODE_CONFIG: pem::EncodeConfig = {
-    let line_ending = if cfg!(target_family = "windows") {
-        pem::LineEnding::CRLF
-    } else {
-        pem::LineEnding::LF
+    let line_ending = match cfg!(target_family = "windows") {
+        true => pem::LineEnding::CRLF,
+        false => pem::LineEnding::LF,
     };
     pem::EncodeConfig::new().set_line_ending(line_ending)
 };
 
-#[derive(Error, Debug)]
+#[derive(Error, Debug, Diagnostic)]
 pub enum InitError {
     #[error("Key generation error during TLS initialization: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::key_generation))]
     KeyGeneration(#[from] rcgen::Error),
 
     #[error("Key invalid format: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::key_invalid_format))]
     KeyInvalidFormat(#[from] FromUtf8Error),
 
     #[error("Key deserialization error: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::key_deserialization))]
     KeyDeserializationError(rcgen::Error),
 
     #[error("Database error during TLS initialization: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::database_error))]
     DatabaseError(#[from] diesel::result::Error),
 
     #[error("Pem deserialization error during TLS initialization: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::pem_deserialization))]
     PemDeserializationError(#[from] rustls::pki_types::pem::Error),
 
     #[error("Database pool acquire error during TLS initialization: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::database_pool_acquire))]
     DatabasePoolAcquire(#[from] db::PoolError),
 }
 
 pub type PemCert = String;
 
-pub fn encode_cert_to_pem(cert: &CertificateDer<'_>) -> PemCert {
+pub fn encode_cert_to_pem(cert: &CertificateDer) -> PemCert {
     pem::encode_config(&Pem::new("CERTIFICATE", cert.to_vec()), ENCODE_CONFIG)
 }
 
-#[expect(
-    unused,
-    reason = "may be needed for future cert rotation implementation"
-)]
+#[allow(unused)]
 struct SerializedTls {
     cert_pem: PemCert,
     cert_key_pem: String,
@@ -87,7 +91,7 @@ impl TlsCa {
 
         let cert_key_pem = certified_issuer.key().serialize_pem();
 
-        #[expect(
+        #[allow(
             clippy::unwrap_used,
             reason = "Broken cert couldn't bootstrap server anyway"
         )]
@@ -110,9 +114,6 @@ impl TlsCa {
             KeyUsagePurpose::DigitalSignature,
             KeyUsagePurpose::KeyEncipherment,
         ];
-        params
-            .subject_alt_names
-            .push(SanType::IpAddress(Ipv4Addr::LOCALHOST.into()));
 
         let mut dn = DistinguishedName::new();
         dn.push(DnType::CommonName, "Arbiter Instance Leaf");
@@ -126,11 +127,7 @@ impl TlsCa {
         })
     }
 
-    #[expect(
-        unused,
-        clippy::unnecessary_wraps,
-        reason = "may be needed for future cert rotation implementation"
-    )]
+    #[allow(unused)]
     fn serialize(&self) -> Result<SerializedTls, InitError> {
         let cert_key_pem = self.issuer.key().serialize_pem();
         Ok(SerializedTls {
@@ -139,10 +136,7 @@ impl TlsCa {
         })
     }
 
-    #[expect(
-        unused,
-        reason = "may be needed for future cert rotation implementation"
-    )]
+    #[allow(unused)]
     fn try_deserialize(cert_pem: &str, cert_key_pem: &str) -> Result<Self, InitError> {
         let keypair =
             KeyPair::from_pem(cert_key_pem).map_err(InitError::KeyDeserializationError)?;
@@ -174,7 +168,8 @@ impl TlsManager {
 
         {
             let mut conn = db.get().await?;
-            conn.transaction(async |conn| {
+            conn.transaction(|conn| {
+                Box::pin(async {
                     let new_tls_history = NewTlsHistory {
                         cert: new_cert.cert.pem(),
                         cert_key: new_cert.cert_key.serialize_pem(),
@@ -185,16 +180,17 @@ impl TlsManager {
                     let inserted_tls_history: i32 = diesel::insert_into(tls_history::table)
                         .values(&new_tls_history)
                         .returning(tls_history::id)
-                    .get_result(&mut *conn)
+                        .get_result(conn)
                         .await?;
 
                     diesel::update(arbiter_settings::table)
                         .set(arbiter_settings::tls_id.eq(inserted_tls_history))
-                    .execute(&mut *conn)
+                        .execute(conn)
                         .await?;
 
                     Result::<_, diesel::result::Error>::Ok(())
                 })
+            })
             .await?;
         }
 
@@ -241,10 +237,10 @@ impl TlsManager {
         }
     }
 
-    pub const fn cert(&self) -> &CertificateDer<'static> {
+    pub fn cert(&self) -> &CertificateDer<'static> {
         &self.cert
     }
-    pub const fn ca_cert(&self) -> &CertificateDer<'static> {
+    pub fn ca_cert(&self) -> &CertificateDer<'static> {
         &self.ca_cert
     }
 

server/crates/arbiter-server/src/crypto/encryption/mod.rs

@@ -1,3 +0,0 @@
-pub mod v1;
-
-pub use v1::*;

server/crates/arbiter-server/src/crypto/encryption/v1.rs

@@ -1,102 +0,0 @@
-use argon2::password_hash::Salt as ArgonSalt;
-use rand::{
-    Rng as _, SeedableRng,
-    rngs::{StdRng, SysRng},
-};
-
-pub const ROOT_KEY_TAG: &[u8] = b"arbiter/seal/v1";
-pub const TAG: &[u8] = b"arbiter/private-key/v1";
-
-pub const NONCE_LENGTH: usize = 24;
-
-#[derive(Default)]
-pub struct Nonce(pub [u8; NONCE_LENGTH]);
-impl Nonce {
-    pub fn increment(&mut self) {
-        for i in (0..self.0.len()).rev() {
-            if let Some(byte) = self.0.get_mut(i) {
-                if *byte == 0xFF {
-                    *byte = 0;
-                } else {
-                    *byte += 1;
-                    break;
-                }
-            }
-        }
-    }
-
-    pub fn to_vec(&self) -> Vec<u8> {
-        self.0.to_vec()
-    }
-}
-impl<'a> TryFrom<&'a [u8]> for Nonce {
-    type Error = ();
-
-    fn try_from(value: &'a [u8]) -> Result<Self, Self::Error> {
-        if value.len() != NONCE_LENGTH {
-            return Err(());
-        }
-        let mut nonce = [0u8; NONCE_LENGTH];
-        nonce.copy_from_slice(value);
-        Ok(Self(nonce))
-    }
-}
-
-pub type Salt = [u8; ArgonSalt::RECOMMENDED_LENGTH];
-
-pub fn generate_salt() -> Salt {
-    let mut salt = Salt::default();
-    let mut rng =
-        StdRng::try_from_rng(&mut SysRng).expect("Rng failure is unrecoverable and should panic");
-    rng.fill_bytes(&mut salt);
-    salt
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::crypto::derive_key;
-    use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
-    #[test]
-    fn derive_seal_key_deterministic() {
-        static PASSWORD: &[u8] = b"password";
-        let mut password = SafeCell::new(PASSWORD.to_vec());
-        let mut password2 = SafeCell::new(PASSWORD.to_vec());
-        let salt = generate_salt();
-
-        let mut key1 = derive_key(&mut password, &salt);
-        let mut key2 = derive_key(&mut password2, &salt);
-
-        let key1_reader = key1.0.read();
-        let key2_reader = key2.0.read();
-
-        assert_eq!(&*key1_reader, &*key2_reader);
-    }
-
-    #[test]
-    fn successful_derive() {
-        static PASSWORD: &[u8] = b"password";
-        let mut password = SafeCell::new(PASSWORD.to_vec());
-        let salt = generate_salt();
-
-        let mut key = derive_key(&mut password, &salt);
-        let key_reader = key.0.read();
-
-        assert_ne!(key_reader.as_slice(), &[0u8; 32][..]);
-    }
-
-    #[test]
-    // We should fuzz this
-    pub fn nonce_increment() {
-        let mut nonce = Nonce([0u8; NONCE_LENGTH]);
-        nonce.increment();
-
-        assert_eq!(
-            nonce.0,
-            [
-                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
-            ]
-        );
-    }
-}

server/crates/arbiter-server/src/crypto/governance.rs

@@ -1,99 +0,0 @@
-//! Canonical encoding and verification of governance vote signatures (§3.3).
-
-use crate::db::models::ProposalId;
-use arbiter_crypto::authn::{self, SigningContext};
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, thiserror::Error)]
-pub enum VerifyError {
-    #[error("Malformed operator public key")]
-    PublicKey,
-    #[error("Malformed vote signature")]
-    Signature,
-    #[error("Signature does not match this vote")]
-    Mismatch,
-}
-
-/// Canonical bytes an operator signs when voting: `proposal_id` as i64 big-endian,
-/// followed by the approve flag as one byte.
-///
-/// The flag is part of the message on purpose: without it an approval could be
-/// replayed as a rejection of the same proposal.
-#[must_use]
-pub fn vote_message(proposal_id: ProposalId, approve: bool) -> Vec<u8> {
-    let mut message = Vec::with_capacity(9);
-    message.extend_from_slice(&i64::from(proposal_id.to_raw()).to_be_bytes());
-    message.push(u8::from(approve));
-    message
-}
-
-/// Verifies a vote signature against an operator's stored public key.
-pub fn verify_vote(
-    public_key: &[u8],
-    proposal_id: ProposalId,
-    approve: bool,
-    signature: &[u8],
-) -> Result<(), VerifyError> {
-    let public_key = authn::PublicKey::try_from(public_key).map_err(|()| VerifyError::PublicKey)?;
-    let signature = authn::Signature::try_from(signature).map_err(|()| VerifyError::Signature)?;
-
-    if public_key.verify_message(
-        &vote_message(proposal_id, approve),
-        SigningContext::GovernanceVote,
-        &signature,
-    ) {
-        Ok(())
-    } else {
-        Err(VerifyError::Mismatch)
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::{VerifyError, verify_vote, vote_message};
-    use crate::db::models::ProposalId;
-    use arbiter_crypto::authn::{SigningContext, SigningKey};
-
-    #[test]
-    fn vote_message_is_the_id_then_the_approve_flag() {
-        let message = vote_message(ProposalId::from_raw(0x0102), true);
-        assert_eq!(message, vec![0, 0, 0, 0, 0, 0, 1, 2, 1]);
-    }
-
-    #[test]
-    fn verify_vote_accepts_a_matching_signature() {
-        let key = SigningKey::generate();
-        let id = ProposalId::from_raw(42);
-        let signature = key
-            .sign_message(&vote_message(id, true), SigningContext::GovernanceVote)
-            .unwrap();
-
-        verify_vote(
-            &key.public_key().to_bytes(),
-            id,
-            true,
-            &signature.to_bytes(),
-        )
-        .expect("a signature over this exact vote must verify");
-    }
-
-    /// The decisive one: an approval must not verify as a rejection of the same
-    /// proposal, or a captured vote could be replayed with its meaning flipped.
-    #[test]
-    fn verify_vote_rejects_a_flipped_approve_flag() {
-        let key = SigningKey::generate();
-        let id = ProposalId::from_raw(42);
-        let signature = key
-            .sign_message(&vote_message(id, true), SigningContext::GovernanceVote)
-            .unwrap();
-
-        assert!(matches!(
-            verify_vote(
-                &key.public_key().to_bytes(),
-                id,
-                false,
-                &signature.to_bytes()
-            ),
-            Err(VerifyError::Mismatch)
-        ));
-    }
-}