Merge branch 'security-hash-revoke_at' of ssh://git.markettakers.org:22222/MarketTakers/arbiter into security-hash-revoke_at

.gitignore

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

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.
+- **`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.
-- **`FlowCoordinator`** — Coordinates cross-connection flow between operators and SDK clients.
+- **`FlowCoordinator`** — Coordinates cross-connection flow 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:**
+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.
-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:
 
-- Methods that return `bool` indicating success/failure or validation state
+Communication between Dart and Rust uses typed **signals** defined in `useragent/native/hub/src/signals/`. After modifying signal structs, regenerate Dart bindings:
-- 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:
 
 ```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

@@ -9,7 +9,7 @@ Arbiter is a permissioned signing service for cryptocurrency wallets. It runs as
 
 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).
+- **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.
 - **Recovery Operator** — A dormant recovery participant with narrowly scoped authority used only for custody recovery and operator replacement.
 
@@ -22,32 +22,30 @@ Arbiter distinguishes two kinds of peers:
 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.
+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 canonical challenge payload with its private key and sends the signature back.
+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.
 
-Authentication challenges are per-connection, ephemeral values. They are not persisted in the peer tables, and peer records store no challenge state.
+### 2.2 User Agent Bootstrap
 
-### 2.2 Operator 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:
 
-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 User Agent.
-
-- **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.
+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 Operator.
+There is no bootstrap mechanism for SDK clients. They must be explicitly approved by an already-registered User Agent.
 
 ---
 
 ## 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.
+When more than one User Agent 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
 
@@ -165,13 +163,13 @@ In both cases, committee formation is a coordinated process. Arbiter does not al
 
 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.
+1. An operator connects to the unbootstrapped vault using a User Agent 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 ordinary operator must connect with a User Agent 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
@@ -193,8 +191,8 @@ The server proves its identity using TLS with a self-signed certificate. The TLS
 
 Peers verify the server by its **public key fingerprint**:
 
-- **Operator (local):** Receives the fingerprint automatically through the bootstrap token.
+- **User Agent (local):** Receives the fingerprint automatically through the bootstrap token.
-- **Operator (remote) / SDK Client:** Must receive the fingerprint out-of-band.
+- **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.
 
@@ -231,11 +229,11 @@ On boot, the root key is encrypted and the server cannot perform any signing ope
 
 ### 6.2 Unseal Flow
 
-To transition to the **Unsealed** state, an Operator must provide the password:
+To transition to the **Unsealed** state, a User Agent must provide the password:
 
-1. The Operator initiates an unseal request.
+1. The User Agent 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.
+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.
@@ -257,7 +255,7 @@ See [IMPLEMENTATION.md](IMPLEMENTATION.md) for the current and planned memory pr
 ### 7.1 Fundamental Rules
 
 - SDK clients have **no access by default**.
-- Access is granted **explicitly** by an Operator.
+- 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.
@@ -277,19 +275,19 @@ sequenceDiagram
     autonumber
     actor SDK as SDK Client
     participant Server
-    participant operator as Operator
+    participant UA as User Agent
 
     SDK->>Server: SignTransactionRequest
     Server->>Server: Resolve wallet and wallet visibility
     alt Visibility approval required
-        Server->>operator: Ask for wallet visibility approval
+        Server->>UA: Ask for wallet visibility approval
-        operator-->>Server: Vote result
+        UA-->>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
+        Server->>UA: Ask for execution / grant approval
-        operator-->>Server: Vote result
+        UA-->>Server: Vote result
         opt Create persistent grant
             Server->>Server: Create and store grant
         end

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.
+- **`FlowCoordinator`** — Coordinates cross-connection flow 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`
+- **Client:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `APPROVAL_DENIED`, `NO_USER_AGENTS_ONLINE`, or `INTERNAL`
-- **Operator:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `BOOTSTRAP_REQUIRED`, `TOKEN_INVALID`, 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:
 
@@ -22,36 +22,45 @@ 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]
+    F -- approved --> F2[Cancel remaining\nUserAgent requests]
-    F2 --> F3[INSERT client]
+    F2 --> F3[INSERT client\nnonce = 1]
-    F3 --> G
+    F3 --> G[Send AuthChallenge\nwith nonce]
 
-    G --> H[Send AuthChallenge\ntimestamp + random bytes]
+    G --> H[Receive AuthChallengeSolution]
-    H --> I[Receive AuthChallengeSolution]
+    H --> I{Signature valid?}
-    I --> K{Signature valid?}
+    I -- no --> Z
-    K -- no --> Z
+    I -- yes --> J([Session started])
-    K -- 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.
+1. Both check the DB → neither is registered.
-- `operator_client` stores the Operator public key and timestamps.
+2. Both request approval from user agents → both receive approval.
-- Neither table stores an authentication nonce, and challenge generation does not update either table.
+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.
 
 ---
 
@@ -62,7 +71,7 @@ The authentication schema stores peer identity, not replay counters:
 
 ### 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.
+User-agent 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
@@ -86,7 +95,7 @@ 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
@@ -141,7 +150,7 @@ flowchart TD
     L -- Yes --> M[Check grant limits]
     L -- No --> N[Start execution or grant voting flow]
 
-    N --> O{Operator decision}
+    N --> O{User-agent decision}
     O -- Reject --> Z4[Return no matching grant error]
     O -- Allow once --> M
     O -- Create grant --> P[Create grant with user-selected limits]

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
 

docs/superpowers/plans/2026-03-28-grant-creation-refactor.md

@@ -111,7 +111,7 @@ String shortAddress(List<int> bytes) {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/utils.dart
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/utils.dart
 ```
 
 Expected: no errors.
@@ -168,7 +168,7 @@ class GrantCreation extends _$GrantCreation {
 - [ ] **Step 2: Run code generator**
 
 ```sh
-cd operator && dart run build_runner build --delete-conflicting-outputs
+cd useragent && dart run build_runner build --delete-conflicting-outputs
 ```
 
 Expected: generates `provider.freezed.dart` and `provider.g.dart`, no errors.
@@ -176,7 +176,7 @@ Expected: generates `provider.freezed.dart` and `provider.g.dart`, no errors.
 - [ ] **Step 3: Verify**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/provider.dart
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/provider.dart
 ```
 
 Expected: no errors.
@@ -204,7 +204,7 @@ jj describe -m "feat(grants): add GrantCreation provider (client selection + gra
 
 ```dart
 // lib/screens/dashboard/evm/grants/create/fields/client_picker_field.dart
-import 'package:arbiter/proto/operator.pb.dart';
+import 'package:arbiter/proto/user_agent.pb.dart';
 import 'package:arbiter/providers/sdk_clients/list.dart';
 import 'package:arbiter/screens/dashboard/evm/grants/create/provider.dart';
 import 'package:flutter/material.dart';
@@ -246,7 +246,7 @@ class ClientPickerField extends ConsumerWidget {
 ```dart
 // lib/screens/dashboard/evm/grants/create/fields/wallet_access_picker_field.dart
 import 'package:arbiter/proto/evm.pb.dart';
-import 'package:arbiter/proto/operator.pb.dart';
+import 'package:arbiter/proto/user_agent.pb.dart';
 import 'package:arbiter/providers/evm/evm.dart';
 import 'package:arbiter/providers/sdk_clients/wallet_access_list.dart';
 import 'package:arbiter/screens/dashboard/evm/grants/create/provider.dart';
@@ -522,7 +522,7 @@ class TransactionRateLimitField extends StatelessWidget {
 - [ ] **Step 8: Verify all field widgets**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/fields/
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/fields/
 ```
 
 Expected: no errors.
@@ -585,7 +585,7 @@ class SharedGrantFields extends StatelessWidget {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/shared_grant_fields.dart
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/shared_grant_fields.dart
 ```
 
 Expected: no errors.
@@ -978,7 +978,7 @@ class _TokenVolumeLimitRow extends HookWidget {
 - [ ] **Step 4: Run code generator for token_transfer_grant.g.dart**
 
 ```sh
-cd operator && dart run build_runner build --delete-conflicting-outputs
+cd useragent && dart run build_runner build --delete-conflicting-outputs
 ```
 
 Expected: generates `token_transfer_grant.g.dart`, no errors.
@@ -986,7 +986,7 @@ Expected: generates `token_transfer_grant.g.dart`, no errors.
 - [ ] **Step 5: Verify**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/grants/
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/grants/
 ```
 
 Expected: no errors.
@@ -1265,7 +1265,7 @@ String _formatError(Object error) {
 - [ ] **Step 2: Verify the full create/ directory**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/
 ```
 
 Expected: no errors.

docs/superpowers/plans/2026-03-28-grant-grid-view.md

@@ -14,24 +14,24 @@
 
 | File | Action | Responsibility |
 |---|---|---|
-| `operator/lib/theme/palette.dart` | Modify | Add `Palette.token` (indigo accent for token-transfer cards) |
+| `useragent/lib/theme/palette.dart` | Modify | Add `Palette.token` (indigo accent for token-transfer cards) |
-| `operator/lib/features/connection/evm/wallet_access.dart` | Modify | Add `listAllWalletAccesses()` function |
+| `useragent/lib/features/connection/evm/wallet_access.dart` | Modify | Add `listAllWalletAccesses()` function |
-| `operator/lib/providers/sdk_clients/wallet_access_list.dart` | Create | `WalletAccessListProvider` — fetches full wallet access list with IDs |
+| `useragent/lib/providers/sdk_clients/wallet_access_list.dart` | Create | `WalletAccessListProvider` — fetches full wallet access list with IDs |
-| `operator/lib/screens/dashboard/evm/grants/widgets/grant_card.dart` | Create | `GrantCard` widget — watches enrichment providers + revoke mutation; one card per grant |
+| `useragent/lib/screens/dashboard/evm/grants/widgets/grant_card.dart` | Create | `GrantCard` widget — watches enrichment providers + revoke mutation; one card per grant |
-| `operator/lib/screens/dashboard/evm/grants/grants.dart` | Create | `EvmGrantsScreen` — watches `evmGrantsProvider`; handles loading/error/empty/data states; renders `GrantCard` list |
+| `useragent/lib/screens/dashboard/evm/grants/grants.dart` | Create | `EvmGrantsScreen` — watches `evmGrantsProvider`; handles loading/error/empty/data states; renders `GrantCard` list |
-| `operator/lib/router.dart` | Modify | Register `EvmGrantsRoute` in dashboard children |
+| `useragent/lib/router.dart` | Modify | Register `EvmGrantsRoute` in dashboard children |
-| `operator/lib/screens/dashboard.dart` | Modify | Add Grants entry to `routes` list and `NavigationDestination` list |
+| `useragent/lib/screens/dashboard.dart` | Modify | Add Grants entry to `routes` list and `NavigationDestination` list |
 
 ---
 
 ## Task 1: Add `Palette.token`
 
 **Files:**
-- Modify: `operator/lib/theme/palette.dart`
+- Modify: `useragent/lib/theme/palette.dart`
 
 - [ ] **Step 1: Add the color**
 
-Replace the contents of `operator/lib/theme/palette.dart` with:
+Replace the contents of `useragent/lib/theme/palette.dart` with:
 
 ```dart
 import 'package:flutter/material.dart';
@@ -48,7 +48,7 @@ class Palette {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && flutter analyze lib/theme/palette.dart
+cd useragent && flutter analyze lib/theme/palette.dart
 ```
 
 Expected: no issues.
@@ -65,20 +65,20 @@ jj new
 ## Task 2: Add `listAllWalletAccesses` feature function
 
 **Files:**
-- Modify: `operator/lib/features/connection/evm/wallet_access.dart`
+- Modify: `useragent/lib/features/connection/evm/wallet_access.dart`
 
 `readClientWalletAccess` (existing) filters the list to one client's wallet IDs and returns `Set<int>`. This new function returns the complete unfiltered list with row IDs so the grant cards can resolve wallet_access_id → wallet + client.
 
 - [ ] **Step 1: Append function**
 
-Add at the bottom of `operator/lib/features/connection/evm/wallet_access.dart`:
+Add at the bottom of `useragent/lib/features/connection/evm/wallet_access.dart`:
 
 ```dart
 Future<List<SdkClientWalletAccess>> listAllWalletAccesses(
   Connection connection,
 ) async {
   final response = await connection.ask(
-    OperatorRequest(listWalletAccess: Empty()),
+    UserAgentRequest(listWalletAccess: Empty()),
   );
   if (!response.hasListWalletAccessResponse()) {
     throw Exception(
@@ -97,7 +97,7 @@ Each returned `SdkClientWalletAccess` has:
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && flutter analyze lib/features/connection/evm/wallet_access.dart
+cd useragent && flutter analyze lib/features/connection/evm/wallet_access.dart
 ```
 
 Expected: no issues.
@@ -114,18 +114,18 @@ jj new
 ## Task 3: Create `WalletAccessListProvider`
 
 **Files:**
-- Create: `operator/lib/providers/sdk_clients/wallet_access_list.dart`
+- Create: `useragent/lib/providers/sdk_clients/wallet_access_list.dart`
-- Generated: `operator/lib/providers/sdk_clients/wallet_access_list.g.dart`
+- Generated: `useragent/lib/providers/sdk_clients/wallet_access_list.g.dart`
 
 Mirrors the structure of `EvmGrants` in `providers/evm/evm_grants.dart` — class-based `@riverpod` with a `refresh()` method.
 
 - [ ] **Step 1: Write the provider**
 
-Create `operator/lib/providers/sdk_clients/wallet_access_list.dart`:
+Create `useragent/lib/providers/sdk_clients/wallet_access_list.dart`:
 
 ```dart
 import 'package:arbiter/features/connection/evm/wallet_access.dart';
-import 'package:arbiter/proto/operator.pb.dart';
+import 'package:arbiter/proto/user_agent.pb.dart';
 import 'package:arbiter/providers/connection/connection_manager.dart';
 import 'package:mtcore/markettakers.dart';
 import 'package:riverpod_annotation/riverpod_annotation.dart';
@@ -165,15 +165,15 @@ class WalletAccessList extends _$WalletAccessList {
 - [ ] **Step 2: Run code generation**
 
 ```sh
-cd operator && dart run build_runner build --delete-conflicting-outputs
+cd useragent && dart run build_runner build --delete-conflicting-outputs
 ```
 
-Expected: `operator/lib/providers/sdk_clients/wallet_access_list.g.dart` created. No errors.
+Expected: `useragent/lib/providers/sdk_clients/wallet_access_list.g.dart` created. No errors.
 
 - [ ] **Step 3: Verify**
 
 ```sh
-cd operator && flutter analyze lib/providers/sdk_clients/
+cd useragent && flutter analyze lib/providers/sdk_clients/
 ```
 
 Expected: no issues.
@@ -190,26 +190,26 @@ jj new
 ## Task 4: Create `GrantCard` widget
 
 **Files:**
-- Create: `operator/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`
+- Create: `useragent/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`
 
 This widget owns all per-card logic: enrichment lookups, revoke action, and rebuild scope. The screen only passes it a `GrantEntry` — the card fetches everything else itself.
 
 **Key types:**
 - `GrantEntry` (from `proto/evm.pb.dart`): `.id`, `.shared.walletAccessId`, `.shared.chainId`, `.specific.whichGrant()`
 - `SpecificGrant_Grant.etherTransfer` / `.tokenTransfer` — enum values for the oneof
-- `SdkClientWalletAccess` (from `proto/operator.pb.dart`): `.id`, `.access.walletId`, `.access.sdkClientId`
+- `SdkClientWalletAccess` (from `proto/user_agent.pb.dart`): `.id`, `.access.walletId`, `.access.sdkClientId`
 - `WalletEntry` (from `proto/evm.pb.dart`): `.id`, `.address` (List<int>)
-- `SdkClientEntry` (from `proto/operator.pb.dart`): `.id`, `.info.name`
+- `SdkClientEntry` (from `proto/user_agent.pb.dart`): `.id`, `.info.name`
 - `revokeEvmGrantMutation` — `Mutation<void>` (global; all revoke buttons disable together while any revoke is in flight)
 - `executeRevokeEvmGrant(ref, grantId: int)` — `Future<void>`
 
 - [ ] **Step 1: Write the widget**
 
-Create `operator/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`:
+Create `useragent/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`:
 
 ```dart
 import 'package:arbiter/proto/evm.pb.dart';
-import 'package:arbiter/proto/operator.pb.dart';
+import 'package:arbiter/proto/user_agent.pb.dart';
 import 'package:arbiter/providers/evm/evm.dart';
 import 'package:arbiter/providers/evm/evm_grants.dart';
 import 'package:arbiter/providers/sdk_clients/list.dart';
@@ -438,7 +438,7 @@ class GrantCard extends ConsumerWidget {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && flutter analyze lib/screens/dashboard/evm/grants/widgets/grant_card.dart
+cd useragent && flutter analyze lib/screens/dashboard/evm/grants/widgets/grant_card.dart
 ```
 
 Expected: no issues.
@@ -455,13 +455,13 @@ jj new
 ## Task 5: Create `EvmGrantsScreen`
 
 **Files:**
-- Create: `operator/lib/screens/dashboard/evm/grants/grants.dart`
+- Create: `useragent/lib/screens/dashboard/evm/grants/grants.dart`
 
 The screen watches only `evmGrantsProvider` for top-level state (loading / error / no connection / empty / data). When there is data it renders a list of `GrantCard` widgets — each card manages its own enrichment subscriptions.
 
 - [ ] **Step 1: Write the screen**
 
-Create `operator/lib/screens/dashboard/evm/grants/grants.dart`:
+Create `useragent/lib/screens/dashboard/evm/grants/grants.dart`:
 
 ```dart
 import 'package:arbiter/proto/evm.pb.dart';
@@ -702,7 +702,7 @@ class EvmGrantsScreen extends ConsumerWidget {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && flutter analyze lib/screens/dashboard/evm/grants/
+cd useragent && flutter analyze lib/screens/dashboard/evm/grants/
 ```
 
 Expected: no issues.
@@ -719,13 +719,13 @@ jj new
 ## Task 6: Wire router and dashboard tab
 
 **Files:**
-- Modify: `operator/lib/router.dart`
+- Modify: `useragent/lib/router.dart`
-- Modify: `operator/lib/screens/dashboard.dart`
+- Modify: `useragent/lib/screens/dashboard.dart`
-- Regenerated: `operator/lib/router.gr.dart`
+- Regenerated: `useragent/lib/router.gr.dart`
 
 - [ ] **Step 1: Add route to `router.dart`**
 
-Replace the contents of `operator/lib/router.dart` with:
+Replace the contents of `useragent/lib/router.dart` with:
 
 ```dart
 import 'package:auto_route/auto_route.dart';
@@ -759,7 +759,7 @@ class Router extends RootStackRouter {
 
 - [ ] **Step 2: Update `dashboard.dart`**
 
-In `operator/lib/screens/dashboard.dart`, replace the `routes` constant:
+In `useragent/lib/screens/dashboard.dart`, replace the `routes` constant:
 
 ```dart
 final routes = [
@@ -800,7 +800,7 @@ destinations: const [
 - [ ] **Step 3: Regenerate router**
 
 ```sh
-cd operator && dart run build_runner build --delete-conflicting-outputs
+cd useragent && dart run build_runner build --delete-conflicting-outputs
 ```
 
 Expected: `lib/router.gr.dart` updated, `EvmGrantsRoute` now available, no errors.
@@ -808,7 +808,7 @@ Expected: `lib/router.gr.dart` updated, `EvmGrantsRoute` now available, no error
 - [ ] **Step 4: Full project verify**
 
 ```sh
-cd operator && flutter analyze
+cd useragent && flutter analyze
 ```
 
 Expected: no issues.

docs/superpowers/specs/2026-03-28-grant-grid-view-design.md

@@ -4,7 +4,7 @@
 
 ## Overview
 
-Add a "Grants" dashboard tab to the Flutter operator app that displays all EVM grants as a card-based grid. Each card shows a compact summary (type, chain, wallet address, client name) with a revoke action. The tab integrates into the existing `AdaptiveScaffold` navigation alongside Wallets, Clients, and About.
+Add a "Grants" dashboard tab to the Flutter user-agent app that displays all EVM grants as a card-based grid. Each card shows a compact summary (type, chain, wallet address, client name) with a revoke action. The tab integrates into the existing `AdaptiveScaffold` navigation alongside Wallets, Clients, and About.
 
 ## Scope
 
@@ -23,7 +23,7 @@ Add a "Grants" dashboard tab to the Flutter operator app that displays all EVM g
 
 ### `walletAccessListProvider`
 
-**File:** `operator/lib/providers/sdk_clients/wallet_access_list.dart`
+**File:** `useragent/lib/providers/sdk_clients/wallet_access_list.dart`
 
 - `@riverpod` class, watches `connectionManagerProvider.future`
 - Returns `List<SdkClientWalletAccess>?` (null when not connected)
@@ -85,7 +85,7 @@ NavigationDestination(
 
 ## Screen: `EvmGrantsScreen`
 
-**File:** `operator/lib/screens/dashboard/evm/grants/grants.dart`
+**File:** `useragent/lib/screens/dashboard/evm/grants/grants.dart`
 
 ```
 Scaffold

mise.lock

@@ -1,51 +1,51 @@
 # @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"
+checksum = "sha256:5c830eae8456569e2f7212434ed9c238f58dca412d76045418ed6d394a755836"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-unknown-linux-gnu.zip"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-aarch64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.linux-arm64-musl"]
-checksum = "sha256:3ba383839044cf9817929435f5ce0027f91d06931e8efb32d942e58d73d92be5"
+checksum = "sha256:5c830eae8456569e2f7212434ed9c238f58dca412d76045418ed6d394a755836"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-unknown-linux-gnu.zip"
+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"
+checksum = "sha256:e825a05603f0bcc4cd9076c4cc8c9abd6d008b7cd07d9aa3cc323ba4b8606651"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-unknown-linux-gnu.zip"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.linux-x64-musl"]
-checksum = "sha256:5de8b87cba67fc8dc3e239d54b6484802ad745a7ae3de76be4fe89661dc52657"
+checksum = "sha256:e825a05603f0bcc4cd9076c4cc8c9abd6d008b7cd07d9aa3cc323ba4b8606651"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-unknown-linux-gnu.zip"
+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"
+checksum = "sha256:fc300d5293b1c770a5aece03a8a193b92e71e87cec726c28096990691a582620"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-apple-darwin.zip"
+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"
+checksum = "sha256:979ffe611327056f4730a1ae71b0209b3b830f58b22c6ed194cda34f55400db2"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-apple-darwin.zip"
+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"
+checksum = "sha256:55836fa1b2c65dc7d61615a4d9368622a0d2371a76d28b9a165e5a3ab6ae32a4"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-pc-windows-msvc.zip"
+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-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"]]
@@ -53,7 +53,7 @@ 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"]]
@@ -65,19 +65,15 @@ version = "0.10.2"
 backend = "cargo:cargo-vet"
 
 [[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.flutter]]
-version = "3.41.7-stable"
+version = "3.38.9-stable"
 backend = "asdf:flutter"
 
 [[tools.protoc]]
@@ -113,44 +109,44 @@ checksum = "sha256:1ebd7c87baffb9f1c47169b640872bf5fb1e4408079c691af527be9561d8f
 url = "https://github.com/protocolbuffers/protobuf/releases/download/v29.6/protoc-29.6-win64.zip"
 
 [[tools.python]]
-version = "3.14.4"
+version = "3.14.3"
 backend = "core:python"
 
 [tools.python."platforms.linux-arm64"]
-checksum = "sha256:b8b597fdb2f8dccdc502c11947b60a4b65eb6bce79cfa60c7ccf9b6e8352c60a"
+checksum = "sha256:53700338695e402a1a1fe22be4a41fbdacc70e22bb308a48eca8ed67cb7992be"
-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"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-aarch64-unknown-linux-gnu-install_only_stripped.tar.gz"
 provenance = "github-attestations"
 
 [tools.python."platforms.linux-arm64-musl"]
-checksum = "sha256:b8b597fdb2f8dccdc502c11947b60a4b65eb6bce79cfa60c7ccf9b6e8352c60a"
+checksum = "sha256:53700338695e402a1a1fe22be4a41fbdacc70e22bb308a48eca8ed67cb7992be"
-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"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-aarch64-unknown-linux-gnu-install_only_stripped.tar.gz"
 provenance = "github-attestations"
 
 [tools.python."platforms.linux-x64"]
-checksum = "sha256:fe9a9c32d13870af632cbac3dfc7528ae53597e94472aa4c7d6a42e8166136cd"
+checksum = "sha256:d7a9f970914bb4c88756fe3bdcc186d4feb90e9500e54f1db47dae4dc9687e39"
-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"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz"
 provenance = "github-attestations"
 
 [tools.python."platforms.linux-x64-musl"]
-checksum = "sha256:fe9a9c32d13870af632cbac3dfc7528ae53597e94472aa4c7d6a42e8166136cd"
+checksum = "sha256:d7a9f970914bb4c88756fe3bdcc186d4feb90e9500e54f1db47dae4dc9687e39"
-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"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz"
 provenance = "github-attestations"
 
 [tools.python."platforms.macos-arm64"]
-checksum = "blake3:0314ec66e0f33ec04959583b5900bc8edae371a396aa96b8874e750d1fe936e6"
+checksum = "sha256:c43aecde4a663aebff99b9b83da0efec506479f1c3f98331442f33d2c43501f9"
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+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-aarch64-apple-darwin-install_only_stripped.tar.gz"
 provenance = "github-attestations"
 
 [tools.python."platforms.macos-x64"]
-checksum = "sha256:d51250a32fa5d9f0799c7bcb71720c27b10a3afd4a7de288120f96085d508a5a"
+checksum = "sha256:9ab41dbc2f100a2a45d1833b9c11165f51051c558b5213eda9a9731d5948a0c0"
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+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-x86_64-apple-darwin-install_only_stripped.tar.gz"
 provenance = "github-attestations"
 
 [tools.python."platforms.windows-x64"]
-checksum = "sha256:a976991dcd085c1bb5d9a8084823a6bc8b7f9b079d8c432574a6ddd68c3a6fe1"
+checksum = "sha256:bbe19034b35b0267176a7442575ae7dc6343480fd4d35598cb7700173d431e09"
-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"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-x86_64-pc-windows-msvc-install_only_stripped.tar.gz"
 provenance = "github-attestations"
 
 [[tools.rust]]
-version = "1.95.0"
+version = "1.93.0"
 backend = "core:rust"

mise.toml

@@ -1,19 +1,18 @@
 [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" }
+"rust" = {version = "1.93.0", components = "clippy"}
-"cargo:cargo-features-manager" = "0.12.0"
+"cargo:cargo-features-manager" = "0.11.1"
-"cargo:cargo-nextest" = "0.9.133"
+"cargo:cargo-nextest" = "0.9.126"
 "cargo:cargo-shear" = "latest"
-"cargo:cargo-insta" = "1.47.2"
+"cargo:cargo-insta" = "1.46.3"
-python = "3.14.4"
+python = "3.14.3"
-ast-grep = "0.42.1"
+ast-grep = "0.42.0"
-"cargo:cargo-edit" = "0.13.10"
+"cargo:cargo-edit" = "0.13.9"
 "cargo:cargo-mutants" = "27.0.0"
-"cargo:flutter_rust_bridge_codegen" = "2.12.0"
 
 [tasks.codegen]
 sources = ['protobufs/*.proto', 'protobufs/**/*.proto']
@@ -22,5 +21,3 @@ run = '''
 dart pub global activate protoc_plugin && \
 protoc --dart_out=grpc:useragent/lib/proto --proto_path=protobufs/ $(find protobufs -name '*.proto' | sort)
 '''
-
-[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/auth.proto

@@ -10,8 +10,8 @@ message AuthChallengeRequest {
 }
 
 message AuthChallenge {
-  uint64 timestamp_nanos = 1;
+  bytes pubkey = 1;
-  bytes random = 2;
+  int32 nonce = 2;
 }
 
 message AuthChallengeSolution {
@@ -24,7 +24,7 @@ enum AuthResult {
   AUTH_RESULT_INVALID_KEY = 2;
   AUTH_RESULT_INVALID_SIGNATURE = 3;
   AUTH_RESULT_APPROVAL_DENIED = 4;
-  AUTH_RESULT_NO_OPERATORS_ONLINE = 5;
+  AUTH_RESULT_NO_USER_AGENTS_ONLINE = 5;
   AUTH_RESULT_INTERNAL = 6;
 }
 

protobufs/evm.proto

@@ -75,7 +75,7 @@ message SpecificGrant {
   }
 }
 
-// --- Operator grant management ---
+// --- UserAgent grant management ---
 message EvmGrantCreateRequest {
   SharedSettings shared = 1;
   SpecificGrant specific = 2;

protobufs/shared/vault.proto

@@ -5,8 +5,7 @@ package arbiter.shared;
 enum VaultState {
   VAULT_STATE_UNSPECIFIED = 0;
   VAULT_STATE_UNBOOTSTRAPPED = 1;
-  VAULT_STATE_BOOSTRAPPING = 2;
+  VAULT_STATE_SEALED = 2;
-  VAULT_STATE_SEALED = 3;
+  VAULT_STATE_UNSEALED = 3;
-  VAULT_STATE_UNSEALED = 4;
+  VAULT_STATE_ERROR = 4;
-  VAULT_STATE_ERROR = 5;
 }

protobufs/user_agent.proto

@@ -1,13 +1,13 @@
 syntax = "proto3";
 
-package arbiter.operator;
+package arbiter.user_agent;
 
-import "operator/auth.proto";
+import "user_agent/auth.proto";
-import "operator/evm.proto";
+import "user_agent/evm.proto";
-import "operator/sdk_client.proto";
+import "user_agent/sdk_client.proto";
-import "operator/vault/vault.proto";
+import "user_agent/vault/vault.proto";
 
-message OperatorRequest {
+message UserAgentRequest {
   int32 id = 16;
   oneof payload {
     auth.Request auth = 1;
@@ -17,7 +17,7 @@ message OperatorRequest {
   }
 }
 
-message OperatorResponse {
+message UserAgentResponse {
   optional int32 id = 16;
   oneof payload {
     auth.Response auth = 1;

protobufs/user_agent/auth.proto

@@ -1,15 +1,22 @@
 syntax = "proto3";
 
-package arbiter.operator.auth;
+package arbiter.user_agent.auth;
+
+enum KeyType {
+  KEY_TYPE_UNSPECIFIED = 0;
+  KEY_TYPE_ED25519 = 1;
+  KEY_TYPE_ECDSA_SECP256K1 = 2;
+  KEY_TYPE_RSA = 3;
+}
 
 message AuthChallengeRequest {
   bytes pubkey = 1;
   optional string bootstrap_token = 2;
+  KeyType key_type = 3;
 }
 
 message AuthChallenge {
-  uint64 timestamp_nanos = 1;
+  int32 nonce = 1;
-  bytes random = 2;
 }
 
 message AuthChallengeSolution {

protobufs/user_agent/evm.proto

@@ -1,6 +1,6 @@
 syntax = "proto3";
 
-package arbiter.operator.evm;
+package arbiter.user_agent.evm;
 
 import "evm.proto";
 import "google/protobuf/empty.proto";

protobufs/user_agent/sdk_client.proto

@@ -1,6 +1,6 @@
 syntax = "proto3";
 
-package arbiter.operator.sdk_client;
+package arbiter.user_agent.sdk_client;
 
 import "shared/client.proto";
 import "google/protobuf/empty.proto";

protobufs/user_agent/vault/bootstrap.proto

@@ -1,6 +1,6 @@
 syntax = "proto3";
 
-package arbiter.operator.vault.bootstrap;
+package arbiter.user_agent.vault.bootstrap;
 
 message BootstrapEncryptedKey {
   bytes nonce = 1;

protobufs/user_agent/vault/unseal.proto

@@ -1,6 +1,6 @@
 syntax = "proto3";
 
-package arbiter.operator.vault.unseal;
+package arbiter.user_agent.vault.unseal;
 
 message UnsealStart {
   bytes client_pubkey = 1;

protobufs/user_agent/vault/vault.proto

@@ -1,11 +1,11 @@
 syntax = "proto3";
 
-package arbiter.operator.vault;
+package arbiter.user_agent.vault;
 
 import "google/protobuf/empty.proto";
 import "shared/vault.proto";
-import "operator/vault/bootstrap.proto";
+import "user_agent/vault/bootstrap.proto";
-import "operator/vault/unseal.proto";
+import "user_agent/vault/unseal.proto";
 
 message Request {
   oneof payload {

server/.cargo/config.toml

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

server/Cargo.toml

@@ -4,167 +4,47 @@ members = [
 ]
 resolver = "3"
 
+[workspace.lints.clippy]
+disallowed-methods = "deny"
+
 
 [workspace.dependencies]
-alloy = "2.0.4"
+tonic = { version = "0.14.5", features = [
-async-trait = "0.1.89"
+    "deflate",
-base64 = "0.22.1"
+    "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"] }
-futures = "0.3.32"
+rand = "0.10.0"
-k256 = { version = "0.13.4", features = ["ecdsa", "pkcs8"] }
+rustls = { version = "0.23.37", features = ["aws-lc-rs", "logging", "prefer-post-quantum", "std"], default-features = false }
-kameo = {git = "https://github.com/hdbg/kameo.git", rev = "805b417"}
-kameo_actors = {git = "https://github.com/hdbg/kameo.git", rev = "805b417"}
-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"
 thiserror = "2.0.18"
-tokio = { version = "1.52.1", features = ["full"] }
+async-trait = "0.1.89"
+futures = "0.3.32"
 tokio-stream = { version = "0.1.18", features = ["full"] }
-tonic = { version = "0.14.5", features = [ "deflate", "gzip", "tls-connect-info", "zstd" ] }
+kameo = "0.19.2"
-tracing = "0.1.44"
+prost-types = { version = "0.14.3", features = ["chrono"] }
 x25519-dalek = { version = "2.0.1", features = ["getrandom"] }
-
+rstest = "0.26.1"
-[workspace.lints.rust]
+rustls-pki-types = "1.14.0"
-missing_unsafe_on_extern = "deny"
+alloy = "1.7.3"
-unsafe_attr_outside_unsafe = "deny"
+rcgen = { version = "0.14.7", features = [
-unsafe_op_in_unsafe_fn = "deny"
+    "aws_lc_rs",
-unstable_features = "deny"
+    "pem",
-
+    "x509-parser",
-deprecated_safe_2024 = "warn"
+    "zeroize",
-ffi_unwind_calls = "warn"
+], default-features = false }
-linker_messages = "warn"
+k256 = { version = "0.13.4", features = ["ecdsa", "pkcs8"] }
-
+rsa = { version = "0.9", features = ["sha2"] }
-elided_lifetimes_in_paths = "warn"
+sha2 = "0.10"
-explicit_outlives_requirements = "warn"
+spki = "0.7"
-impl-trait-overcaptures = "warn"
+prost = "0.14.3"
-impl-trait-redundant-captures = "warn"
+miette = { version = "7.6.0", features = ["fancy", "serde"] }
-redundant_lifetimes = "warn"
+mutants = "0.0.4"
-single_use_lifetimes = "warn"
+ml-dsa = { version = "0.1.0-rc.8", features = ["zeroize"] }
-unused_lifetimes = "warn"
+base64 = "0.22.1"
-
+hmac = "0.12.1"
-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"
-integer_division = "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

server/clippy.toml

@@ -7,22 +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

server/crates/arbiter-client/Cargo.toml

@@ -21,9 +21,6 @@ tokio.workspace = true
 tokio-stream.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
+rand.workspace = true
-
-[lib]
-doctest = false

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

@@ -1,8 +1,4 @@
-use crate::{
+use arbiter_crypto::authn::{CLIENT_CONTEXT, SigningKey, format_challenge};
-    storage::StorageError,
-    transport::{ClientTransport, next_request_id},
-};
-use arbiter_crypto::authn::{self, CLIENT_CONTEXT, SigningKey};
 use arbiter_proto::{
     ClientMetadata,
     proto::{
@@ -20,31 +16,33 @@ use arbiter_proto::{
     },
 };
 
-use chrono::DateTime;
+use crate::{
+    storage::StorageError,
+    transport::{ClientTransport, next_request_id},
+};
 
 #[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")]
+    #[error("Client approval denied by User Agent")]
-    NoOperatorsOnline,
+    ApprovalDenied,
 
-    #[error("Signing key storage error")]
+    #[error("No User Agents online to approve client")]
-    Storage(#[from] StorageError),
+    NoUserAgentsOnline,
 
     #[error("Unexpected auth response payload")]
     UnexpectedAuthResponse,
+
+    #[error("Signing key storage error")]
+    Storage(#[from] StorageError),
 }
 
 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::NoUserAgentsOnline => AuthError::NoUserAgentsOnline,
         AuthResult::Unspecified
         | AuthResult::Success
         | AuthResult::InvalidKey
@@ -57,7 +55,7 @@ async fn send_auth_challenge_request(
     transport: &mut ClientTransport,
     metadata: ClientMetadata,
     key: &SigningKey,
-) -> Result<(), AuthError> {
+) -> std::result::Result<(), AuthError> {
     transport
         .send(ClientRequest {
             request_id: next_request_id(),
@@ -78,7 +76,7 @@ async fn send_auth_challenge_request(
 
 async fn receive_auth_challenge(
     transport: &mut ClientTransport,
-) -> Result<AuthChallenge, AuthError> {
+) -> std::result::Result<AuthChallenge, AuthError> {
     let response = transport
         .recv()
         .await
@@ -99,16 +97,8 @@ async fn send_auth_challenge_solution(
     transport: &mut ClientTransport,
     key: &SigningKey,
     challenge: AuthChallenge,
-) -> Result<(), AuthError> {
+) -> std::result::Result<(), AuthError> {
-    let timestamp = DateTime::from_timestamp_nanos(challenge.timestamp_nanos as i64);
+    let challenge_payload = format_challenge(challenge.nonce, &challenge.pubkey);
-    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, CLIENT_CONTEXT)
         .map_err(|_| AuthError::UnexpectedAuthResponse)?
@@ -127,7 +117,9 @@ async fn send_auth_challenge_solution(
         .map_err(|_| AuthError::UnexpectedAuthResponse)
 }
 
-async fn receive_auth_confirmation(transport: &mut ClientTransport) -> Result<(), AuthError> {
+async fn receive_auth_confirmation(
+    transport: &mut ClientTransport,
+) -> std::result::Result<(), AuthError> {
     let response = transport
         .recv()
         .await
@@ -148,11 +140,11 @@ async fn receive_auth_confirmation(transport: &mut ClientTransport) -> Result<()
     }
 }
 
-pub async fn authenticate(
+pub(crate) async fn authenticate(
     transport: &mut ClientTransport,
     metadata: ClientMetadata,
     key: &SigningKey,
-) -> Result<(), AuthError> {
+) -> std::result::Result<(), AuthError> {
     send_auth_challenge_request(transport, metadata, key).await?;
     let challenge = receive_auth_challenge(transport).await?;
     send_auth_challenge_solution(transport, key, challenge).await?;

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

@@ -1,8 +1,8 @@
+use std::io::{self, Write};
+
 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...");
@@ -29,16 +29,16 @@ async fn main() {
         }
     };
 
-    println!("{url:#?}");
+    println!("{:#?}", url);
 
     let metadata = ClientMetadata {
-        name: "arbiter-client test_connect".to_owned(),
+        name: "arbiter-client test_connect".to_string(),
-        description: Some("Manual connection smoke test".to_owned()),
+        description: Some("Manual connection smoke test".to_string()),
-        version: Some(env!("CARGO_PKG_VERSION").to_owned()),
+        version: Some(env!("CARGO_PKG_VERSION").to_string()),
     };
 
     match ArbiterClient::connect(url, metadata).await {
         Ok(_) => println!("Connected and authenticated successfully."),
-        Err(err) => eprintln!("Failed to connect: {err:#?}"),
+        Err(err) => eprintln!("Failed to connect: {:#?}", err),
     }
 }

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

@@ -1,55 +1,50 @@
-#[cfg(feature = "evm")]
+use arbiter_crypto::authn::SigningKey;
-use crate::wallets::evm::ArbiterEvmWallet;
+use arbiter_proto::{
+    ClientMetadata, proto::arbiter_service_client::ArbiterServiceClient, url::ArbiterUrl,
+};
+use std::sync::Arc;
+use tokio::sync::{Mutex, mpsc};
+use tokio_stream::wrappers::ReceiverStream;
+use tonic::transport::ClientTlsConfig;
+
 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 std::sync::Arc;
+#[cfg(feature = "evm")]
-use tokio::sync::{Mutex, mpsc};
+use crate::wallets::evm::ArbiterEvmWallet;
-use tokio_stream::wrappers::ReceiverStream;
-use tonic::transport::ClientTlsConfig;
 
 #[derive(Debug, thiserror::Error)]
-pub enum ArbiterClientError {
+pub enum Error {
-    #[error("Authentication error")]
+    #[error("gRPC error")]
-    Authentication(#[from] AuthError),
+    Grpc(#[from] tonic::Status),
 
     #[error("Could not establish connection")]
     Connection(#[from] tonic::transport::Error),
 
-    #[error("gRPC error")]
+    #[error("Invalid server URI")]
-    Grpc(#[from] tonic::Status),
+    InvalidUri(#[from] http::uri::InvalidUri),
 
     #[error("Invalid CA certificate")]
     InvalidCaCert(#[from] webpki::Error),
 
-    #[error("Invalid server URI")]
+    #[error("Authentication error")]
-    InvalidUri(#[from] http::uri::InvalidUri),
+    Authentication(#[from] AuthError),
 
     #[error("Storage error")]
     Storage(#[from] StorageError),
 }
 
 pub struct ArbiterClient {
-    #[expect(
+    #[allow(dead_code)]
-        dead_code,
-        reason = "transport will be used in future methods for sending requests and receiving responses"
-    )]
     transport: Arc<Mutex<ClientTransport>>,
 }
 
 impl ArbiterClient {
-    pub async fn connect(
+    pub async fn connect(url: ArbiterUrl, metadata: ClientMetadata) -> Result<Self, Error> {
-        url: ArbiterUrl,
-        metadata: ClientMetadata,
-    ) -> Result<Self, ArbiterClientError> {
         let storage = FileSigningKeyStorage::from_default_location()?;
         Self::connect_with_storage(url, metadata, &storage).await
     }
@@ -58,7 +53,7 @@ impl ArbiterClient {
         url: ArbiterUrl,
         metadata: ClientMetadata,
         storage: &S,
-    ) -> Result<Self, ArbiterClientError> {
+    ) -> Result<Self, Error> {
         let key = storage.load_or_create()?;
         Self::connect_with_key(url, metadata, key).await
     }
@@ -67,7 +62,7 @@ impl ArbiterClient {
         url: ArbiterUrl,
         metadata: ClientMetadata,
         key: SigningKey,
-    ) -> Result<Self, ArbiterClientError> {
+    ) -> Result<Self, Error> {
         let anchor = webpki::anchor_from_trusted_cert(&url.ca_cert)?.to_owned();
         let tls = ClientTlsConfig::new().trust_anchor(anchor);
 
@@ -94,8 +89,7 @@ impl ArbiterClient {
     }
 
     #[cfg(feature = "evm")]
-    #[expect(clippy::unused_async, reason = "false positive")]
+    pub async fn evm_wallets(&self) -> Result<Vec<ArbiterEvmWallet>, Error> {
-    pub async fn evm_wallets(&self) -> Result<Vec<ArbiterEvmWallet>, ArbiterClientError> {
         todo!("fetch EVM wallet list from server")
     }
 }

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

@@ -5,7 +5,7 @@ mod transport;
 pub mod wallets;
 
 pub use auth::AuthError;
-pub use client::{ArbiterClient, ArbiterClientError};
+pub use client::{ArbiterClient, Error};
 pub use storage::{FileSigningKeyStorage, SigningKeyStorage, StorageError};
 
 #[cfg(feature = "evm")]

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

@@ -1,19 +1,18 @@
 use arbiter_crypto::authn::SigningKey;
 use arbiter_proto::home_path;
-
 use std::path::{Path, PathBuf};
 
 #[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),
+
+    #[error("Invalid signing key length in storage: expected {expected} bytes, got {actual} bytes")]
+    InvalidKeyLength { expected: usize, actual: usize },
 }
 
 pub trait SigningKeyStorage {
-    fn load_or_create(&self) -> Result<SigningKey, StorageError>;
+    fn load_or_create(&self) -> std::result::Result<SigningKey, StorageError>;
 }
 
 #[derive(Debug, Clone)]
@@ -28,11 +27,11 @@ impl FileSigningKeyStorage {
         Self { path: path.into() }
     }
 
-    pub fn from_default_location() -> Result<Self, StorageError> {
+    pub fn from_default_location() -> std::result::Result<Self, StorageError> {
         Ok(Self::new(home_path()?.join(Self::DEFAULT_FILE_NAME)))
     }
 
-    fn read_key(path: &Path) -> Result<SigningKey, StorageError> {
+    fn read_key(path: &Path) -> std::result::Result<SigningKey, StorageError> {
         let bytes = std::fs::read(path)?;
         let raw: [u8; 32] =
             bytes
@@ -46,7 +45,7 @@ impl FileSigningKeyStorage {
 }
 
 impl SigningKeyStorage for FileSigningKeyStorage {
-    fn load_or_create(&self) -> Result<SigningKey, StorageError> {
+    fn load_or_create(&self) -> std::result::Result<SigningKey, StorageError> {
         if let Some(parent) = self.path.parent() {
             std::fs::create_dir_all(parent)?;
         }
@@ -126,7 +125,7 @@ mod tests {
                 assert_eq!(expected, 32);
                 assert_eq!(actual, 31);
             }
-            other @ StorageError::Io(_) => panic!("unexpected error: {other:?}"),
+            other => panic!("unexpected error: {other:?}"),
         }
 
         std::fs::remove_file(path).expect("temp key file should be removable");

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

@@ -1,17 +1,16 @@
 use arbiter_proto::proto::client::{ClientRequest, ClientResponse};
-
 use std::sync::atomic::{AtomicI32, Ordering};
 use tokio::sync::mpsc;
 
-pub const BUFFER_LENGTH: usize = 16;
+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 {
+pub(crate) enum ClientSignError {
     #[error("Transport channel closed")]
     ChannelClosed,
 
@@ -19,23 +18,27 @@ pub enum ClientSignError {
     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<(), ClientSignError> {
         self.sender
             .send(request)
             .await
             .map_err(|_| ClientSignError::ChannelClosed)
     }
 
-    pub(crate) async fn recv(&mut self) -> Result<ClientResponse, ClientSignError> {
+    pub(crate) async fn recv(&mut self) -> std::result::Result<ClientResponse, ClientSignError> {
         match self.receiver.message().await {
             Ok(Some(resp)) => Ok(resp),
-            Ok(None) | Err(_) => Err(ClientSignError::ConnectionClosed),
+            Ok(None) => Err(ClientSignError::ConnectionClosed),
+            Err(_) => Err(ClientSignError::ConnectionClosed),
         }
     }
 }

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

@@ -1,4 +1,13 @@
-use crate::transport::{ClientTransport, next_request_id};
+use alloy::{
+    consensus::SignableTransaction,
+    network::TxSigner,
+    primitives::{Address, B256, ChainId, Signature},
+    signers::{Error, Result, Signer},
+};
+use async_trait::async_trait;
+use std::sync::Arc;
+use tokio::sync::Mutex;
+
 use arbiter_proto::proto::{
     client::{
         ClientRequest,
@@ -16,15 +25,7 @@ use arbiter_proto::proto::{
     shared::evm::TransactionEvalError,
 };
 
-use alloy::{
+use crate::transport::{ClientTransport, next_request_id};
-    consensus::SignableTransaction,
-    network::TxSigner,
-    primitives::{Address, B256, ChainId, Signature},
-    signers::{Error, Result, Signer},
-};
-use async_trait::async_trait;
-use std::sync::Arc;
-use tokio::sync::Mutex;
 
 /// A typed error payload returned by [`ArbiterEvmWallet`] transaction signing.
 ///
@@ -58,11 +59,7 @@ pub struct ArbiterEvmWallet {
 }
 
 impl ArbiterEvmWallet {
-    #[expect(
+    pub(crate) fn new(transport: Arc<Mutex<ClientTransport>>, address: Address) -> Self {
-        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 {
         Self {
             transport,
             address,
@@ -70,12 +67,11 @@ impl ArbiterEvmWallet {
         }
     }
 
-    pub const fn address(&self) -> Address {
+    pub fn address(&self) -> Address {
         self.address
     }
 
-    #[must_use]
+    pub fn with_chain_id(mut self, chain_id: ChainId) -> Self {
-    pub const fn with_chain_id(mut self, chain_id: ChainId) -> Self {
         self.chain_id = Some(chain_id);
         self
     }
@@ -150,7 +146,6 @@ impl TxSigner<Signature> for ArbiterEvmWallet {
             .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(

server/crates/arbiter-crypto/Cargo.toml

@@ -6,20 +6,16 @@ edition = "2024"
 [dependencies]
 ml-dsa = {workspace = true, optional = true }
 rand = {workspace = true, optional = true}
+base64 = {workspace = true, optional = true }
 memsafe = {version = "0.4.0", 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"]
+authn = ["dep:ml-dsa", "dep:rand", "dep:base64"]
 safecell = ["dep:memsafe"]
-
-[lib]
-doctest = false

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

@@ -1,65 +1,16 @@
-use chrono::{DateTime, Utc};
+use base64::{Engine as _, prelude::BASE64_STANDARD};
 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;
 
 pub static CLIENT_CONTEXT: &[u8] = b"arbiter_client";
-pub static OPERATOR_CONTEXT: &[u8] = b"arbiter_operator";
+pub static USERAGENT_CONTEXT: &[u8] = b"arbiter_user_agent";
 
-const NONCE_SIZE: usize = 32;
+pub fn format_challenge(nonce: i32, pubkey: &[u8]) -> Vec<u8> {
-
+    let concat_form = format!("{}:{}", nonce, BASE64_STANDARD.encode(pubkey));
-#[derive(Debug, Clone, Copy, PartialEq, Eq, thiserror::Error)]
+    concat_form.into_bytes()
-#[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;
@@ -84,11 +35,12 @@ impl PublicKey {
         self.0.encode().0.to_vec()
     }
 
-    #[must_use]
+    pub fn verify(&self, nonce: i32, context: &[u8], signature: &Signature) -> bool {
-    pub fn verify(&self, challenge: &AuthChallenge, context: &[u8], signature: &Signature) -> bool {
+        self.0.verify_with_context(
-        let challenge = challenge.format();
+            &format_challenge(nonce, &self.to_bytes()),
-        self.0
+            context,
-            .verify_with_context(&challenge, context, &signature.0)
+            &signature.0,
+        )
     }
 }
 
@@ -122,14 +74,11 @@ impl SigningKey {
             .map(Into::into)
     }
 
-    pub fn sign_challenge(
+    pub fn sign_challenge(&self, nonce: i32, context: &[u8]) -> Result<Signature, Error> {
-        &self,
+        self.sign_message(
-        challenge: &AuthChallenge,
+            &format_challenge(nonce, &self.public_key().to_bytes()),
-        context: &[u8],
+            context,
-    ) -> Result<Signature, Error> {
+        )
-        let challenge = challenge.format();
-
-        self.sign_message(&challenge, context)
     }
 }
 
@@ -190,9 +139,7 @@ impl TryFrom<&'_ [u8]> for Signature {
 mod tests {
     use ml_dsa::{KeyGen, MlDsa87, signature::Keypair as _};
 
-    use crate::authn::AuthChallenge;
+    use super::{CLIENT_CONTEXT, PublicKey, Signature, SigningKey, USERAGENT_CONTEXT};
-
-    use super::{CLIENT_CONTEXT, PublicKey, Signature, SigningKey, OPERATOR_CONTEXT};
 
     #[test]
     fn public_key_round_trip_decodes() {
@@ -221,13 +168,13 @@ mod tests {
     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 nonce = 17;
         let signature = key
-            .sign_challenge(&challenge, CLIENT_CONTEXT)
+            .sign_challenge(nonce, CLIENT_CONTEXT)
             .expect("signature should be created");
 
-        assert!(public_key.verify(&challenge, CLIENT_CONTEXT, &signature));
+        assert!(public_key.verify(nonce, CLIENT_CONTEXT, &signature));
-        assert!(!public_key.verify(&challenge, OPERATOR_CONTEXT, &signature));
+        assert!(!public_key.verify(nonce, USERAGENT_CONTEXT, &signature));
     }
 
     #[test]
@@ -237,16 +184,10 @@ mod tests {
 
         assert_eq!(restored.public_key(), original.public_key());
 
-        let challenge = AuthChallenge::generate(&mut rand::rng());
-
         let signature = restored
-            .sign_challenge(&challenge, CLIENT_CONTEXT)
+            .sign_challenge(9, CLIENT_CONTEXT)
             .expect("signature should be created");
 
-        assert!(
+        assert!(restored.public_key().verify(9, CLIENT_CONTEXT, &signature));
-            restored
-                .public_key()
-                .verify(&challenge, CLIENT_CONTEXT, &signature)
-        );
     }
 }

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

@@ -1,6 +1,5 @@
-use std::collections::HashSet;
-
 pub use hmac::digest::Digest;
+use std::collections::HashSet;
 
 /// Deterministically hash a value by feeding its fields into the hasher in a consistent order.
 #[diagnostic::on_unimplemented(
@@ -50,7 +49,7 @@ impl<T: Hashable + PartialOrd> Hashable for Vec<T> {
     }
 }
 
-impl<T: Hashable + PartialOrd, S: std::hash::BuildHasher> Hashable for HashSet<T, S> {
+impl<T: Hashable + PartialOrd> Hashable for HashSet<T> {
     fn hash<H: Digest>(&self, hasher: &mut H) {
         let ref_sorted = {
             let mut sorted = self.iter().collect::<Vec<_>>();

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

@@ -3,5 +3,3 @@ pub mod authn;
 pub mod hashing;
 #[cfg(feature = "safecell")]
 pub mod safecell;
-
-pub use x_wing;

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

@@ -1,9 +1,7 @@
+use std::ops::{Deref, DerefMut};
+use std::{any::type_name, fmt};
+
 use memsafe::MemSafe;
-use std::{
-    any::type_name,
-    fmt,
-    ops::{Deref, DerefMut},
-};
 
 pub trait SafeCellHandle<T> {
     type CellRead<'a>: Deref<Target = T>
@@ -22,7 +20,7 @@ pub trait SafeCellHandle<T> {
     fn read(&mut self) -> Self::CellRead<'_>;
     fn write(&mut self) -> Self::CellWrite<'_>;
 
-    fn new_inline_default<F>(f: F) -> Self
+    fn new_inline<F>(f: F) -> Self
     where
         Self: Sized,
         T: Default,
@@ -31,19 +29,11 @@ pub trait SafeCellHandle<T> {
         let mut cell = Self::new(T::default());
         {
             let mut handle = cell.write();
-            f(&mut *handle);
+            f(handle.deref_mut());
         }
         cell
     }
 
-    fn new_inline<F>(f: Box<F>) -> Self
-    where
-        Self: Sized,
-        F: for<'a> FnOnce() -> T,
-    {
-        Self::new(f())
-    }
-
     #[inline(always)]
     fn read_inline<F, R>(&mut self, f: F) -> R
     where

server/crates/arbiter-macros/Cargo.toml

@@ -5,7 +5,6 @@ edition = "2024"
 
 [lib]
 proc-macro = true
-doctest = false
 
 [dependencies]
 proc-macro2 = "1.0"

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

@@ -1,8 +1,10 @@
-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};
+use syn::parse_quote;
+use syn::spanned::Spanned;
+use syn::{DataStruct, DeriveInput, Fields, Generics, Index};
+
+use crate::utils::{HASHABLE_TRAIT_PATH, HMAC_DIGEST_PATH};
 
 pub(crate) fn derive(input: &DeriveInput) -> TokenStream {
     match &input.data {
@@ -18,7 +20,7 @@ pub(crate) fn derive(input: &DeriveInput) -> TokenStream {
     }
 }
 
-fn hashable_struct(input: &DeriveInput, struct_data: &DataStruct) -> TokenStream {
+fn hashable_struct(input: &DeriveInput, struct_data: &syn::DataStruct) -> TokenStream {
     let ident = &input.ident;
     let hashable_trait = HASHABLE_TRAIT_PATH.to_path();
     let hmac_digest = HMAC_DIGEST_PATH.to_path();

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

@@ -1,24 +1,19 @@
-pub(crate) struct ToPath(pub &'static str);
+pub struct ToPath(pub &'static str);
 
 impl ToPath {
-    pub(crate) fn to_path(&self) -> syn::Path {
+    pub fn to_path(&self) -> syn::Path {
         syn::parse_str(self.0).expect("Invalid path")
     }
 }
 
 macro_rules! ensure_path {
-    ($path:path as $name:ident) => {
+    ($path:path) => {{
-        const _: () = {
         #[cfg(test)]
-            #[expect(
+        #[expect(unused_imports)]
-                unused_imports,
-                reason = "Ensures the path is valid and will cause a compile error if not"
-            )]
         use $path as _;
-        };
+        ToPath(stringify!($path))
-        pub(crate) const $name: ToPath = ToPath(stringify!($path));
+    }};
-    };
 }
 
-ensure_path!(::arbiter_crypto::hashing::Hashable as HASHABLE_TRAIT_PATH);
+pub const HASHABLE_TRAIT_PATH: ToPath = ensure_path!(::arbiter_crypto::hashing::Hashable);
-ensure_path!(::arbiter_crypto::hashing::Digest as HMAC_DIGEST_PATH);
+pub const HMAC_DIGEST_PATH: ToPath = ensure_path!(::arbiter_crypto::hashing::Digest);

server/crates/arbiter-proto/Cargo.toml

@@ -9,6 +9,7 @@ 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
 kameo.workspace = true
@@ -18,18 +19,18 @@ thiserror.workspace = true
 rustls-pki-types.workspace = true
 base64.workspace = true
 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

@@ -10,7 +10,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         .compile_protos(
             &[
                 format!("{}/arbiter.proto", PROTOBUF_DIR),
-                format!("{}/operator.proto", PROTOBUF_DIR),
+                format!("{}/user_agent.proto", PROTOBUF_DIR),
                 format!("{}/client.proto", PROTOBUF_DIR),
                 format!("{}/evm.proto", PROTOBUF_DIR),
             ],

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

@@ -12,30 +12,30 @@ pub mod proto {
         }
     }
 
-    pub mod operator {
+    pub mod user_agent {
-        tonic::include_proto!("arbiter.operator");
+        tonic::include_proto!("arbiter.user_agent");
 
         pub mod auth {
-            tonic::include_proto!("arbiter.operator.auth");
+            tonic::include_proto!("arbiter.user_agent.auth");
         }
 
         pub mod evm {
-            tonic::include_proto!("arbiter.operator.evm");
+            tonic::include_proto!("arbiter.user_agent.evm");
         }
 
         pub mod sdk_client {
-            tonic::include_proto!("arbiter.operator.sdk_client");
+            tonic::include_proto!("arbiter.user_agent.sdk_client");
         }
 
         pub mod vault {
-            tonic::include_proto!("arbiter.operator.vault");
+            tonic::include_proto!("arbiter.user_agent.vault");
 
             pub mod bootstrap {
-                tonic::include_proto!("arbiter.operator.vault.bootstrap");
+                tonic::include_proto!("arbiter.user_agent.vault.bootstrap");
             }
 
             pub mod unseal {
-                tonic::include_proto!("arbiter.operator.vault.unseal");
+                tonic::include_proto!("arbiter.user_agent.vault.unseal");
             }
         }
     }

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

@@ -1,6 +1,7 @@
+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";
@@ -104,7 +105,7 @@ 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

@@ -9,8 +9,8 @@ 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 = { version = "2.3.7", features = ["chrono", "returning_clauses_for_sqlite_3_35", "serde_json", "time", "uuid"] }
-diesel-async = { version = "0.9.0", features = [
+diesel-async = { version = "0.8.0", features = [
     "bb8",
     "migrations",
     "sqlite",
@@ -27,12 +27,17 @@ tokio.workspace = true
 rustls.workspace = true
 smlang.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
+zeroize = { version = "1.8.2", features = ["std", "simd"] }
 kameo.workspace = true
 chacha20poly1305 = { version = "0.10.1", features = ["std"] }
 argon2 = { version = "0.5.3", features = ["zeroize"] }
@@ -41,22 +46,22 @@ strum = { version = "0.28.0", features = ["derive"] }
 pem = "3.0.6"
 sha2.workspace = true
 hmac.workspace = true
+spki.workspace = true
 alloy.workspace = true
 prost-types.workspace = true
+prost.workspace = true
 arbiter-tokens-registry.path = "../arbiter-tokens-registry"
 anyhow = "1.0.102"
+serde_with = "3.18.0"
 mutants.workspace = true
 subtle = "2.6.1"
+ml-dsa.workspace = true
+ed25519-dalek.workspace = true
 x25519-dalek.workspace = true
 k256.workspace = true
-kameo_actors.workspace = true
-vsss-rs = "5.4.0"
 
 [dev-dependencies]
+insta = "1.46.3"
 proptest = "1.11.0"
 rstest.workspace = true
 test-log = { version = "0.2", default-features = false, features = ["trace"] }
-ml-dsa.workspace = true
-
-[lib]
-doctest = false

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

@@ -43,24 +43,15 @@ create table if not exists arbiter_settings (
 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),
     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 unique index if not exists uniq_useragent_client_public_key on useragent_client (public_key, key_type);
-
-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,
-
-    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,
@@ -82,6 +73,7 @@ create unique index if not exists uniq_metadata_binding_client on client_metadat
 
 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')),

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

@@ -1,20 +1,20 @@
-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::{RngExt, distr::Alphanumeric, make_rng, rngs::StdRng};
 use subtle::ConstantTimeEq as _;
 use thiserror::Error;
 
+use crate::db::{self, DatabasePool, schema};
 const TOKEN_LENGTH: usize = 64;
 
 pub async fn generate_token() -> Result<String, std::io::Error> {
     let rng: StdRng = make_rng();
 
-    let token = rng.sample_iter(Alphanumeric).take(TOKEN_LENGTH).fold(
+    let token: String = rng.sample_iter(Alphanumeric).take(TOKEN_LENGTH).fold(
-        String::default(),
+        Default::default(),
         |mut accum, char| {
             accum += char.to_string().as_str();
             accum
@@ -31,11 +31,11 @@ pub enum Error {
     #[error("Database error: {0}")]
     Database(#[from] db::PoolError),
 
-    #[error("I/O error: {0}")]
-    Io(#[from] std::io::Error),
-
     #[error("Database query error: {0}")]
     Query(#[from] diesel::result::Error),
+
+    #[error("I/O error: {0}")]
+    Io(#[from] std::io::Error),
 }
 
 #[derive(Actor)]
@@ -48,7 +48,7 @@ impl Bootstrapper {
         let row_count: i64 = {
             let mut conn = db.get().await?;
 
-            schema::operator::table
+            schema::useragent_client::table
                 .count()
                 .get_result(&mut conn)
                 .await?
@@ -69,13 +69,16 @@ impl Bootstrapper {
 impl Bootstrapper {
     #[message]
     pub fn is_correct_token(&self, token: String) -> bool {
-        self.token.as_ref().is_some_and(|expected| {
+        match &self.token {
+            Some(expected) => {
                 let expected_bytes = expected.as_bytes();
                 let token_bytes = token.as_bytes();
 
                 let choice = expected_bytes.ct_eq(token_bytes);
                 bool::from(choice)
-        })
+            }
+            None => false,
+        }
     }
 
     #[message]

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

@@ -0,0 +1,423 @@
+use arbiter_crypto::authn::{self, CLIENT_CONTEXT};
+use arbiter_proto::{
+    ClientMetadata,
+    transport::{Bi, expect_message},
+};
+use chrono::Utc;
+use diesel::{
+    ExpressionMethods as _, OptionalExtension as _, QueryDsl as _, SelectableHelper as _,
+    dsl::insert_into, update,
+};
+use diesel_async::RunQueryDsl as _;
+use kameo::{actor::ActorRef, error::SendError};
+use tracing::error;
+
+use crate::{
+    actors::{
+        client::{ClientConnection, ClientCredentials, ClientProfile},
+        flow_coordinator::{self, RequestClientApproval},
+        keyholder::KeyHolder,
+    },
+    crypto::integrity::{self, AttestationStatus},
+    db::{
+        self,
+        models::{ProgramClientMetadata, SqliteTimestamp},
+        schema::program_client,
+    },
+};
+
+#[derive(thiserror::Error, Debug, Clone, PartialEq, Eq)]
+pub enum Error {
+    #[error("Database pool unavailable")]
+    DatabasePoolUnavailable,
+    #[error("Database operation failed")]
+    DatabaseOperationFailed,
+    #[error("Integrity check failed")]
+    IntegrityCheckFailed,
+    #[error("Invalid challenge solution")]
+    InvalidChallengeSolution,
+    #[error("Client approval request failed")]
+    ApproveError(#[from] ApproveError),
+    #[error("Transport error")]
+    Transport,
+}
+
+impl From<diesel::result::Error> for Error {
+    fn from(e: diesel::result::Error) -> Self {
+        error!(?e, "Database error");
+        Self::DatabaseOperationFailed
+    }
+}
+
+#[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(flow_coordinator::ApprovalError),
+}
+
+#[derive(Debug, Clone)]
+pub enum Inbound {
+    AuthChallengeRequest {
+        pubkey: authn::PublicKey,
+        metadata: ClientMetadata,
+    },
+    AuthChallengeSolution {
+        signature: authn::Signature,
+    },
+}
+
+#[derive(Debug, Clone)]
+pub enum Outbound {
+    AuthChallenge {
+        pubkey: authn::PublicKey,
+        nonce: i32,
+    },
+    AuthSuccess,
+}
+
+/// Returns the current nonce and client ID for a registered client.
+/// Returns `None` if the pubkey is not registered.
+async fn get_current_nonce_and_id(
+    db: &db::DatabasePool,
+    pubkey: &authn::PublicKey,
+) -> Result<Option<(i32, i32)>, Error> {
+    let pubkey_bytes = pubkey.to_bytes();
+    let mut conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::DatabasePoolUnavailable
+    })?;
+    program_client::table
+        .filter(program_client::public_key.eq(&pubkey_bytes))
+        .select((program_client::id, program_client::nonce))
+        .first::<(i32, i32)>(&mut conn)
+        .await
+        .optional()
+        .map_err(|e| {
+            error!(error = ?e, "Database error");
+            Error::DatabaseOperationFailed
+        })
+}
+
+async fn verify_integrity(
+    db: &db::DatabasePool,
+    keyholder: &ActorRef<KeyHolder>,
+    pubkey: &authn::PublicKey,
+) -> Result<(), Error> {
+    let mut db_conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::DatabasePoolUnavailable
+    })?;
+
+    let (id, nonce) = get_current_nonce_and_id(db, pubkey).await?.ok_or_else(|| {
+        error!("Client not found during integrity verification");
+        Error::DatabaseOperationFailed
+    })?;
+
+    let attestation = integrity::verify_entity(
+        &mut db_conn,
+        keyholder,
+        &ClientCredentials {
+            pubkey: pubkey.clone(),
+            nonce,
+        },
+        id,
+    )
+    .await
+    .map_err(|e| {
+        error!(?e, "Integrity verification failed");
+        Error::IntegrityCheckFailed
+    })?;
+
+    if attestation != AttestationStatus::Attested {
+        error!("Integrity attestation unavailable for client {id}");
+        return Err(Error::IntegrityCheckFailed);
+    }
+
+    Ok(())
+}
+
+/// Atomically increments the nonce and re-signs the integrity envelope.
+/// Returns the new nonce, which is used as the challenge nonce.
+async fn create_nonce(
+    db: &db::DatabasePool,
+    keyholder: &ActorRef<KeyHolder>,
+    pubkey: &authn::PublicKey,
+) -> Result<i32, Error> {
+    let pubkey_bytes = pubkey.to_bytes();
+    let pubkey = pubkey.clone();
+
+    let mut conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::DatabasePoolUnavailable
+    })?;
+
+    conn.exclusive_transaction(|conn| {
+        let keyholder = keyholder.clone();
+        let pubkey = pubkey.clone();
+        Box::pin(async move {
+            let (id, new_nonce): (i32, i32) = update(program_client::table)
+                .filter(program_client::public_key.eq(&pubkey_bytes))
+                .set(program_client::nonce.eq(program_client::nonce + 1))
+                .returning((program_client::id, program_client::nonce))
+                .get_result(conn)
+                .await?;
+
+            integrity::sign_entity(
+                conn,
+                &keyholder,
+                &ClientCredentials {
+                    pubkey: pubkey.clone(),
+                    nonce: new_nonce,
+                },
+                id,
+            )
+            .await
+            .map_err(|e| {
+                error!(?e, "Integrity sign failed after nonce update");
+                Error::DatabaseOperationFailed
+            })?;
+
+            Ok(new_nonce)
+        })
+    })
+    .await
+}
+
+async fn approve_new_client(
+    actors: &crate::actors::GlobalActors,
+    profile: ClientProfile,
+) -> Result<(), Error> {
+    let result = actors
+        .flow_coordinator
+        .ask(RequestClientApproval { client: profile })
+        .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 flow coordinator failed");
+            Err(Error::ApproveError(ApproveError::Internal))
+        }
+    }
+}
+
+async fn insert_client(
+    db: &db::DatabasePool,
+    keyholder: &ActorRef<KeyHolder>,
+    pubkey: &authn::PublicKey,
+    metadata: &ClientMetadata,
+) -> Result<i32, Error> {
+    use crate::db::schema::{client_metadata, program_client};
+    let pubkey = pubkey.clone();
+    let metadata = metadata.clone();
+
+    let mut conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::DatabasePoolUnavailable
+    })?;
+
+    conn.exclusive_transaction(|conn| {
+        let keyholder = keyholder.clone();
+        let pubkey = pubkey.clone();
+        Box::pin(async move {
+            const NONCE_START: i32 = 1;
+
+            let metadata_id = insert_into(client_metadata::table)
+                .values((
+                    client_metadata::name.eq(&metadata.name),
+                    client_metadata::description.eq(&metadata.description),
+                    client_metadata::version.eq(&metadata.version),
+                ))
+                .returning(client_metadata::id)
+                .get_result::<i32>(conn)
+                .await?;
+
+            let client_id = insert_into(program_client::table)
+                .values((
+                    program_client::public_key.eq(pubkey.to_bytes()),
+                    program_client::metadata_id.eq(metadata_id),
+                    program_client::nonce.eq(NONCE_START),
+                ))
+                .on_conflict_do_nothing()
+                .returning(program_client::id)
+                .get_result::<i32>(conn)
+                .await?;
+
+            integrity::sign_entity(
+                conn,
+                &keyholder,
+                &ClientCredentials {
+                    pubkey: pubkey.clone(),
+                    nonce: NONCE_START,
+                },
+                client_id,
+            )
+            .await
+            .map_err(|e| {
+                error!(error = ?e, "Failed to sign integrity tag for new client key");
+                Error::DatabaseOperationFailed
+            })?;
+
+            Ok(client_id)
+        })
+    })
+    .await
+}
+
+async fn sync_client_metadata(
+    db: &db::DatabasePool,
+    client_id: i32,
+    metadata: &ClientMetadata,
+) -> Result<(), Error> {
+    use crate::db::schema::{client_metadata, client_metadata_history};
+
+    let now = SqliteTimestamp(Utc::now());
+
+    let mut conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::DatabasePoolUnavailable
+    })?;
+
+    conn.exclusive_transaction(|conn| {
+        let metadata = metadata.clone();
+        Box::pin(async move {
+            let (current_metadata_id, current): (i32, ProgramClientMetadata) =
+                program_client::table
+                    .find(client_id)
+                    .inner_join(client_metadata::table)
+                    .select((
+                        program_client::metadata_id,
+                        ProgramClientMetadata::as_select(),
+                    ))
+                    .first(conn)
+                    .await?;
+
+            let unchanged = current.name == metadata.name
+                && current.description == metadata.description
+                && current.version == metadata.version;
+            if unchanged {
+                return Ok(());
+            }
+
+            insert_into(client_metadata_history::table)
+                .values((
+                    client_metadata_history::metadata_id.eq(current_metadata_id),
+                    client_metadata_history::client_id.eq(client_id),
+                ))
+                .execute(conn)
+                .await?;
+
+            let metadata_id = insert_into(client_metadata::table)
+                .values((
+                    client_metadata::name.eq(&metadata.name),
+                    client_metadata::description.eq(&metadata.description),
+                    client_metadata::version.eq(&metadata.version),
+                ))
+                .returning(client_metadata::id)
+                .get_result::<i32>(conn)
+                .await?;
+
+            update(program_client::table.find(client_id))
+                .set((
+                    program_client::metadata_id.eq(metadata_id),
+                    program_client::updated_at.eq(now),
+                ))
+                .execute(conn)
+                .await?;
+
+            Ok::<(), diesel::result::Error>(())
+        })
+    })
+    .await
+    .map_err(|e| {
+        error!(error = ?e, "Database error");
+        Error::DatabaseOperationFailed
+    })
+}
+
+async fn challenge_client<T>(
+    transport: &mut T,
+    pubkey: authn::PublicKey,
+    nonce: i32,
+) -> Result<(), Error>
+where
+    T: Bi<Inbound, Result<Outbound, Error>> + ?Sized,
+{
+    transport
+        .send(Ok(Outbound::AuthChallenge {
+            pubkey: pubkey.clone(),
+            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
+    })?;
+
+    if !pubkey.verify(nonce, CLIENT_CONTEXT, &signature) {
+        error!("Challenge solution verification failed");
+        return Err(Error::InvalidChallengeSolution);
+    }
+
+    Ok(())
+}
+
+pub async fn authenticate<T>(props: &mut ClientConnection, transport: &mut T) -> Result<i32, Error>
+where
+    T: Bi<Inbound, Result<Outbound, Error>> + Send + ?Sized,
+{
+    let Some(Inbound::AuthChallengeRequest { pubkey, metadata }) = transport.recv().await else {
+        return Err(Error::Transport);
+    };
+
+    let client_id = match get_current_nonce_and_id(&props.db, &pubkey).await? {
+        Some((id, _)) => {
+            verify_integrity(&props.db, &props.actors.key_holder, &pubkey).await?;
+            id
+        }
+        None => {
+            approve_new_client(
+                &props.actors,
+                ClientProfile {
+                    pubkey: pubkey.clone(),
+                    metadata: metadata.clone(),
+                },
+            )
+            .await?;
+            insert_client(&props.db, &props.actors.key_holder, &pubkey, &metadata).await?
+        }
+    };
+
+    sync_client_metadata(&props.db, client_id, &metadata).await?;
+    let challenge_nonce = create_nonce(&props.db, &props.actors.key_holder, &pubkey).await?;
+    challenge_client(transport, pubkey, challenge_nonce).await?;
+
+    transport
+        .send(Ok(Outbound::AuthSuccess))
+        .await
+        .map_err(|e| {
+            error!(error = ?e, "Failed to send auth success");
+            Error::Transport
+        })?;
+
+    Ok(client_id)
+}

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

@@ -1,22 +1,24 @@
-use crate::{
-    actors::GlobalActors, crypto::integrity::Integrable, db, peers::client::session::ClientSession,
-};
 use arbiter_crypto::authn;
-use arbiter_macros::Hashable;
 use arbiter_proto::{ClientMetadata, transport::Bi};
-
 use kameo::actor::Spawn;
 use tracing::{error, info};
 
+use crate::{
+    actors::{GlobalActors, client::session::ClientSession},
+    crypto::integrity::Integrable,
+    db,
+};
+
 #[derive(Debug, Clone)]
 pub struct ClientProfile {
     pub pubkey: authn::PublicKey,
     pub metadata: ClientMetadata,
 }
 
-#[derive(Hashable)]
+#[derive(arbiter_macros::Hashable)]
 pub struct ClientCredentials {
     pub pubkey: authn::PublicKey,
+    pub nonce: i32,
 }
 
 impl Integrable for ClientCredentials {
@@ -29,7 +31,7 @@ pub struct ClientConnection {
 }
 
 impl ClientConnection {
-    pub const fn new(db: db::DatabasePool, actors: GlobalActors) -> Self {
+    pub fn new(db: db::DatabasePool, actors: GlobalActors) -> Self {
         Self { db, actors }
     }
 }
@@ -42,7 +44,7 @@ where
     T: Bi<auth::Inbound, Result<auth::Outbound, auth::Error>> + Send + ?Sized,
 {
     let fut = auth::authenticate(&mut props, transport);
-    println!("authenticate future size: {}", size_of_val(&fut));
+    println!("authenticate future size: {}", std::mem::size_of_val(&fut));
     match fut.await {
         Ok(client_id) => {
             ClientSession::spawn(ClientSession::new(props, client_id));

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

@@ -1,26 +1,27 @@
-use super::ClientConnection;
+use kameo::{Actor, messages};
+use tracing::error;
+
+use alloy::{consensus::TxEip1559, primitives::Address, signers::Signature};
+
 use crate::{
     actors::{
         GlobalActors,
+        client::ClientConnection,
         evm::{ClientSignTransaction, SignTransactionError},
         flow_coordinator::RegisterClient,
-        vault::VaultState,
+        keyholder::KeyHolderState,
     },
     db,
     evm::VetError,
 };
 
-use alloy::{consensus::TxEip1559, primitives::Address, signers::Signature};
-use kameo::{Actor, messages};
-use tracing::error;
-
 pub struct ClientSession {
     props: ClientConnection,
     client_id: i32,
 }
 
 impl ClientSession {
-    pub(crate) const fn new(props: ClientConnection, client_id: i32) -> Self {
+    pub(crate) fn new(props: ClientConnection, client_id: i32) -> Self {
         Self { props, client_id }
     }
 }
@@ -28,13 +29,13 @@ impl ClientSession {
 #[messages]
 impl ClientSession {
     #[message]
-    pub(crate) async fn handle_query_vault_state(&mut self) -> Result<VaultState, Error> {
+    pub(crate) async fn handle_query_vault_state(&mut self) -> Result<KeyHolderState, Error> {
-        use crate::actors::vault::GetState;
+        use crate::actors::keyholder::GetState;
 
-        let vault_state = match self.props.actors.vault.ask(GetState {}).await {
+        let vault_state = match self.props.actors.key_holder.ask(GetState {}).await {
             Ok(state) => state,
             Err(err) => {
-                error!(?err, actor = "client", "vault.query.failed");
+                error!(?err, actor = "client", "keyholder.query.failed");
                 return Err(Error::Internal);
             }
         };
@@ -91,7 +92,7 @@ impl Actor for ClientSession {
 }
 
 impl ClientSession {
-    pub const fn new_test(db: db::DatabasePool, actors: GlobalActors) -> Self {
+    pub fn new_test(db: db::DatabasePool, actors: GlobalActors) -> Self {
         let props = ClientConnection::new(db, actors);
         Self {
             props,

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

@@ -1,9 +1,17 @@
+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};
+use rand::{SeedableRng, rng, rngs::StdRng};
+
 use crate::{
-    actors::vault::{CreateNew, Decrypt, Vault},
+    actors::keyholder::{CreateNew, Decrypt, KeyHolder},
     crypto::integrity,
     db::{
         DatabaseError, DatabasePool,
-        models::{self, EvmWalletId},
+        models::{self},
         schema,
     },
     evm::{
@@ -16,16 +24,6 @@ use crate::{
 };
 use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
 
-use alloy::{
-    consensus::TxEip1559, network::TxSignerSync as _, 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};
-use rand::{SeedableRng, rng, rngs::StdRng};
-
 pub use crate::evm::safe_signer;
 
 #[derive(Debug, thiserror::Error)]
@@ -36,11 +34,11 @@ pub enum SignTransactionError {
     #[error("Database error: {0}")]
     Database(#[from] DatabaseError),
 
-    #[error("Vault error: {0}")]
+    #[error("Keyholder error: {0}")]
-    Vault(#[from] crate::actors::vault::Error),
+    Keyholder(#[from] crate::actors::keyholder::Error),
 
-    #[error("Vault mailbox error")]
+    #[error("Keyholder mailbox error")]
-    VaultSend,
+    KeyholderSend,
 
     #[error("Signing error: {0}")]
     Signing(#[from] alloy::signers::Error),
@@ -51,11 +49,11 @@ pub enum SignTransactionError {
 
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
-    #[error("Vault error: {0}")]
+    #[error("Keyholder error: {0}")]
-    Vault(#[from] crate::actors::vault::Error),
+    Keyholder(#[from] crate::actors::keyholder::Error),
 
-    #[error("Vault mailbox error")]
+    #[error("Keyholder mailbox error")]
-    VaultSend,
+    KeyholderSend,
 
     #[error("Database error: {0}")]
     Database(#[from] DatabaseError),
@@ -66,20 +64,20 @@ pub enum Error {
 
 #[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(), keyholder.clone());
         Self {
-            vault,
+            keyholder,
             db,
             rng,
             engine,
@@ -96,10 +94,10 @@ impl EvmActor {
         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)
@@ -116,7 +114,7 @@ impl EvmActor {
     }
 
     #[message]
-    pub async fn list_wallets(&self) -> Result<Vec<(EvmWalletId, Address)>, Error> {
+    pub async fn list_wallets(&self) -> Result<Vec<(i32, Address)>, Error> {
         let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
         let rows: Vec<models::EvmWallet> = schema::evm_wallet::table
             .select(models::EvmWallet::as_select())
@@ -134,7 +132,7 @@ impl EvmActor {
 #[messages]
 impl EvmActor {
     #[message]
-    pub async fn operator_create_grant(
+    pub async fn useragent_create_grant(
         &mut self,
         basic: SharedGrantSettings,
         grant: SpecificGrant,
@@ -160,10 +158,9 @@ impl EvmActor {
     }
 
     #[message]
-    #[expect(clippy::unused_async, reason = "reserved for impl")]
+    pub async fn useragent_delete_grant(&mut self, _grant_id: i32) -> Result<(), Error> {
-    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 vault = self.vault.clone();
+        // let keyholder = self.keyholder.clone();
 
         // diesel_async::AsyncConnection::transaction(&mut conn, |conn| {
         //     Box::pin(async move {
@@ -186,7 +183,7 @@ impl EvmActor {
     }
 
     #[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)),
@@ -257,12 +254,12 @@ impl EvmActor {
         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)?;
 
@@ -270,6 +267,7 @@ impl EvmActor {
             .evaluate_transaction(wallet_access, transaction.clone(), RunKind::Execution)
             .await?;
 
+        use alloy::network::TxSignerSync as _;
         Ok(signer.sign_transaction_sync(&mut transaction)?)
     }
 }

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

@@ -1,26 +1,25 @@
-use crate::{
+use std::ops::ControlFlow;
-    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;
+
+use crate::actors::{
+    client::ClientProfile,
+    flow_coordinator::ApprovalError,
+    user_agent::{UserAgentSession, session::BeginNewClientApproval},
+};
 
 pub struct Args {
     pub client: ClientProfile,
-    pub operators: Vec<ActorRef<OperatorSession>>,
+    pub user_agents: Vec<ActorRef<UserAgentSession>>,
     pub reply: ReplySender<Result<bool, ApprovalError>>,
 }
 
 pub struct ClientApprovalController {
-    /// Number of operators that have not yet responded (approval or denial) or died.
+    /// Number of UAs that have not yet responded (approval or denial) or died.
     pending: usize,
     /// Number of approvals received so far.
     approved: usize,
@@ -42,21 +41,20 @@ impl Actor for ClientApprovalController {
     async fn on_start(
         Args {
             client,
-            operators,
+            mut user_agents,
             reply,
         }: Self::Args,
         actor_ref: ActorRef<Self>,
     ) -> Result<Self, Self::Error> {
         let this = Self {
-            pending: operators.len(),
+            pending: user_agents.len(),
             approved: 0,
             reply: Some(reply),
         };
 
-        for operator in operators {
+        for user_agent in user_agents.drain(..) {
-            actor_ref.link(&operator).await;
+            actor_ref.link(&user_agent).await;
-
+            let _ = user_agent
-            let _ = operator
                 .tell(BeginNewClientApproval {
                     client: client.clone(),
                     controller: actor_ref.clone(),
@@ -73,10 +71,10 @@ impl Actor for ClientApprovalController {
         _: ActorId,
         _: ActorStopReason,
     ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
-        // A linked operator died before responding — counts as a non-approval.
+        // A linked UA 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.
+            // At least one UA didn't approve: deny.
             self.send_reply(Ok(false));
             return Ok(ControlFlow::Break(ActorStopReason::Normal));
         }
@@ -87,7 +85,7 @@ impl Actor for ClientApprovalController {
 #[messages]
 impl ClientApprovalController {
     #[message(ctx)]
-    pub fn client_approval_answer(&mut self, approved: bool, ctx: &mut Context<Self, ()>) {
+    pub async 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));
@@ -99,7 +97,7 @@ impl ClientApprovalController {
         self.pending = self.pending.saturating_sub(1);
 
         if self.pending == 0 {
-            // Every connected operator approved.
+            // Every connected UA approved.
             self.send_reply(Ok(true));
             ctx.stop();
         }

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

@@ -1,10 +1,4 @@
-use crate::{
+use std::{collections::HashMap, ops::ControlFlow};
-    actors::{
-        flow_coordinator::client_connect_approval::ClientApprovalController,
-        operator_registry::{GetConnected, OperatorRegistry},
-    },
-    peers::client::{ClientProfile, session::ClientSession},
-};
 
 use kameo::{
     Actor,
@@ -13,23 +7,20 @@ use kameo::{
     prelude::{ActorStopReason, Context, WeakActorRef},
     reply::DelegatedReply,
 };
-use std::{collections::HashMap, ops::ControlFlow};
 use tracing::info;
 
+use crate::actors::{
+    client::{ClientProfile, session::ClientSession},
+    flow_coordinator::client_connect_approval::ClientApprovalController,
+    user_agent::session::UserAgentSession,
+};
+
 pub mod client_connect_approval;
 
+#[derive(Default)]
 pub struct FlowCoordinator {
+    pub user_agents: HashMap<ActorId, ActorRef<UserAgentSession>>,
     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 {
@@ -47,7 +38,13 @@ impl Actor for FlowCoordinator {
         id: ActorId,
         _: ActorStopReason,
     ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
-        if self.clients.remove(&id).is_some() {
+        if self.user_agents.remove(&id).is_some() {
+            info!(
+                ?id,
+                actor = "FlowCoordinator",
+                event = "useragent.disconnected"
+            );
+        } else if self.clients.remove(&id).is_some() {
             info!(
                 ?id,
                 actor = "FlowCoordinator",
@@ -66,12 +63,23 @@ impl Actor for FlowCoordinator {
 
 #[derive(Debug, thiserror::Error, Clone, PartialEq, Eq, Hash)]
 pub enum ApprovalError {
-    #[error("No operators connected")]
+    #[error("No user agents connected")]
-    NoOperatorsConnected,
+    NoUserAgentsConnected,
 }
 
 #[messages]
 impl FlowCoordinator {
+    #[message(ctx)]
+    pub async fn register_user_agent(
+        &mut self,
+        actor: ActorRef<UserAgentSession>,
+        ctx: &mut Context<Self, ()>,
+    ) {
+        info!(id = %actor.id(), actor = "FlowCoordinator", 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,
@@ -93,19 +101,15 @@ impl FlowCoordinator {
             unreachable!("Expected `request_client_approval` to have callback channel");
         };
 
-        let Ok(refs) = self.operator_registry.ask(GetConnected).await else {
+        let refs: Vec<_> = self.user_agents.values().cloned().collect();
-            reply_sender.send(Err(ApprovalError::NoOperatorsConnected));
-            return reply;
-        };
-
         if refs.is_empty() {
-            reply_sender.send(Err(ApprovalError::NoOperatorsConnected));
+            reply_sender.send(Err(ApprovalError::NoUserAgentsConnected));
             return reply;
         }
 
         ClientApprovalController::spawn(client_connect_approval::Args {
             client,
-            operators: refs,
+            user_agents: refs,
             reply: reply_sender,
         });
 

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

@@ -0,0 +1,454 @@
+use chrono::Utc;
+use diesel::{
+    ExpressionMethods as _, OptionalExtension, QueryDsl, SelectableHelper,
+    dsl::{insert_into, update},
+};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use hmac::Mac as _;
+use kameo::{Actor, Reply, messages};
+use strum::{EnumDiscriminants, IntoDiscriminant};
+use tracing::{error, info};
+
+use crate::crypto::{
+    KeyCell, derive_key,
+    encryption::v1::{self, Nonce},
+    integrity::v1::HmacSha256,
+};
+use crate::db::{
+    self,
+    models::{self, RootKeyHistory},
+    schema::{self},
+};
+use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
+
+#[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)]
+pub enum Error {
+    #[error("Keyholder is already bootstrapped")]
+    AlreadyBootstrapped,
+    #[error("Keyholder is not bootstrapped")]
+    NotBootstrapped,
+    #[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,
+}
+
+/// 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 = 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 = derive_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 = Nonce::default();
+        let data_encryption_nonce = 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(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 = derive_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: KeyCell::try_from(root_key).map_err(|err| {
+                error!(?err, "Broken database: invalid encryption key size");
+                Error::BrokenDatabase
+            })?,
+        };
+
+        info!("Keyholder unsealed successfully");
+
+        Ok(())
+    }
+
+    #[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 sign_integrity(&mut self, mac_input: Vec<u8>) -> Result<(i32, Vec<u8>), Error> {
+        let State::Unsealed {
+            root_key,
+            root_key_history_id,
+        } = &mut self.state
+        else {
+            return Err(Error::NotBootstrapped);
+        };
+
+        let mut hmac = root_key
+            .0
+            .read_inline(|k| match HmacSha256::new_from_slice(k) {
+                Ok(v) => v,
+                Err(_) => unreachable!("HMAC accepts keys of any size"),
+            });
+        hmac.update(&root_key_history_id.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: i32,
+    ) -> Result<bool, Error> {
+        let State::Unsealed {
+            root_key,
+            root_key_history_id,
+        } = &mut self.state
+        else {
+            return Err(Error::NotBootstrapped);
+        };
+
+        if *root_key_history_id != key_version {
+            return Ok(false);
+        }
+
+        let mut hmac = root_key
+            .0
+            .read_inline(|k| match HmacSha256::new_from_slice(k) {
+                Ok(v) => v,
+                Err(_) => unreachable!("HMAC accepts keys of any size"),
+            });
+        hmac.update(&key_version.to_be_bytes());
+        hmac.update(&mac_input);
+
+        Ok(hmac.verify_slice(&expected_mac).is_ok())
+    }
+
+    #[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};
+    use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
+
+    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

@@ -1,59 +1,47 @@
+use kameo::actor::{ActorRef, Spawn};
+use thiserror::Error;
+
 use crate::{
     actors::{
         bootstrap::Bootstrapper, evm::EvmActor, flow_coordinator::FlowCoordinator,
-        operator_registry::OperatorRegistry, vault::Vault,
+        keyholder::KeyHolder,
     },
     db,
 };
 
-use kameo::actor::{ActorRef, Spawn};
-use kameo_actors::{DeliveryStrategy, message_bus::MessageBus};
-use thiserror::Error;
-
 pub mod bootstrap;
-pub mod evm;
+pub mod client;
+mod evm;
 pub mod flow_coordinator;
-pub mod operator_registry;
+pub mod keyholder;
-pub mod vault;
+pub mod user_agent;
 
 #[derive(Error, Debug)]
 pub enum SpawnError {
     #[error("Failed to spawn Bootstrapper actor")]
     Bootstrapper(#[from] bootstrap::Error),
 
-    #[error("Failed to spawn Vault actor")]
+    #[error("Failed to spawn KeyHolder actor")]
-    Vault(#[from] vault::Error),
+    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 flow_coordinator: ActorRef<FlowCoordinator>,
-    pub operator_registry: ActorRef<OperatorRegistry>,
     pub evm: ActorRef<EvmActor>,
-    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 message_bus = Self::spawn_message_bus();
+        let key_holder = KeyHolder::spawn(KeyHolder::new(db.clone()).await?);
-        let key_holder = Vault::spawn(Vault::new(db.clone(), message_bus.clone()).await?);
-        let operator_registry = OperatorRegistry::spawn(OperatorRegistry::default());
         Ok(Self {
             bootstrapper: Bootstrapper::spawn(Bootstrapper::new(&db).await?),
             evm: EvmActor::spawn(EvmActor::new(key_holder.clone(), db)),
-            vault: key_holder,
+            key_holder,
-            flow_coordinator: FlowCoordinator::spawn(FlowCoordinator::new(
+            flow_coordinator: FlowCoordinator::spawn(FlowCoordinator::default()),
-                operator_registry.clone(),
-            )),
-            operator_registry,
-            events: message_bus,
         })
     }
 }

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/user_agent/auth.rs

@@ -1,14 +1,13 @@
-use super::{Credentials, OperatorConnection};
+use arbiter_crypto::authn;
-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::{
+    UserAgentConnection,
+    auth::state::{AuthContext, AuthStateMachine},
+};
 mod state;
+use state::*;
 
 #[derive(Debug, Clone)]
 pub enum Inbound {
@@ -47,7 +46,7 @@ impl From<diesel::result::Error> for Error {
 
 #[derive(Debug, Clone)]
 pub enum Outbound {
-    AuthChallenge { challenge: AuthChallenge },
+    AuthChallenge { nonce: i32 },
     AuthSuccess,
 }
 
@@ -55,11 +54,12 @@ fn parse_auth_event(payload: Inbound) -> AuthEvents {
     match payload {
         Inbound::AuthChallengeRequest {
             pubkey,
-            bootstrap_token,
+            bootstrap_token: None,
-        } => AuthEvents::AuthRequest(ChallengeRequest {
+        } => 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 +69,22 @@ fn parse_auth_event(payload: Inbound) -> AuthEvents {
 }
 
 pub async fn authenticate<T>(
-    props: &mut OperatorConnection,
+    props: &mut UserAgentConnection,
-    transport: &mut T,
+    transport: T,
-) -> Result<Credentials, Error>
+) -> Result<authn::PublicKey, 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 +1,318 @@
+use arbiter_crypto::authn::{self, USERAGENT_CONTEXT};
+use arbiter_proto::transport::Bi;
+use diesel::{ExpressionMethods as _, OptionalExtension as _, QueryDsl, update};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use kameo::actor::ActorRef;
+use tracing::error;
+
+use super::Error;
+use crate::{
+    actors::{
+        bootstrap::ConsumeToken,
+        keyholder::KeyHolder,
+        user_agent::{UserAgentConnection, UserAgentCredentials, auth::Outbound},
+    },
+    crypto::integrity,
+    db::{DatabasePool, schema::useragent_client},
+};
+
+pub struct ChallengeRequest {
+    pub pubkey: authn::PublicKey,
+}
+
+pub struct BootstrapAuthRequest {
+    pub pubkey: authn::PublicKey,
+    pub token: String,
+}
+
+pub struct ChallengeContext {
+    pub challenge_nonce: i32,
+    pub key: authn::PublicKey,
+}
+
+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(authn::PublicKey),
+        SentChallenge(ChallengeContext) + ReceivedSolution(ChallengeSolution) / async verify_solution = AuthOk(authn::PublicKey),
+    }
+);
+
+/// Returns the current nonce, ready to use for the challenge nonce.
+async fn get_current_nonce_and_id(
+    db: &DatabasePool,
+    key: &authn::PublicKey,
+) -> Result<(i32, 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 {
+                useragent_client::table
+                    .filter(useragent_client::public_key.eq(key.to_bytes()))
+                    .select((useragent_client::id, useragent_client::nonce))
+                    .first::<(i32, i32)>(conn)
+                    .await
+            })
+        })
+        .await
+        .optional()
+        .map_err(|e| {
+            error!(error = ?e, "Database error");
+            Error::internal("Database operation failed")
+        })?
+        .ok_or_else(|| {
+            error!(?key, "Public key not found in database");
+            Error::UnregisteredPublicKey
+        })
+}
+
+async fn verify_integrity(
+    db: &DatabasePool,
+    keyholder: &ActorRef<KeyHolder>,
+    pubkey: &authn::PublicKey,
+) -> Result<(), Error> {
+    let mut db_conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::internal("Database unavailable")
+    })?;
+
+    let (id, nonce) = get_current_nonce_and_id(db, pubkey).await?;
+
+    let _result = integrity::verify_entity(
+        &mut db_conn,
+        keyholder,
+        &UserAgentCredentials {
+            pubkey: pubkey.clone(),
+            nonce,
+        },
+        id,
+    )
+    .await
+    .map_err(|e| {
+        error!(?e, "Integrity verification failed");
+        Error::internal("Integrity verification failed")
+    })?;
+
+    Ok(())
+}
+
+async fn create_nonce(
+    db: &DatabasePool,
+    keyholder: &ActorRef<KeyHolder>,
+    pubkey: &authn::PublicKey,
+) -> Result<i32, Error> {
+    let mut db_conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::internal("Database unavailable")
+    })?;
+    let new_nonce = db_conn
+        .exclusive_transaction(|conn| {
+            Box::pin(async move {
+                let (id, new_nonce): (i32, i32) = update(useragent_client::table)
+                    .filter(useragent_client::public_key.eq(pubkey.to_bytes()))
+                    .set(useragent_client::nonce.eq(useragent_client::nonce + 1))
+                    .returning((useragent_client::id, useragent_client::nonce))
+                    .get_result(conn)
+                    .await
+                    .map_err(|e| {
+                        error!(error = ?e, "Database error");
+                        Error::internal("Database operation failed")
+                    })?;
+
+                integrity::sign_entity(
+                    conn,
+                    keyholder,
+                    &UserAgentCredentials {
+                        pubkey: pubkey.clone(),
+                        nonce: new_nonce,
+                    },
+                    id,
+                )
+                .await
+                .map_err(|e| {
+                    error!(?e, "Integrity signature update failed");
+                    Error::internal("Database error")
+                })?;
+
+                Result::<_, Error>::Ok(new_nonce)
+            })
+        })
+        .await?;
+    Ok(new_nonce)
+}
+
+async fn register_key(
+    db: &DatabasePool,
+    keyholder: &ActorRef<KeyHolder>,
+    pubkey: &authn::PublicKey,
+) -> Result<(), Error> {
+    let pubkey_bytes = pubkey.to_bytes();
+    let mut conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::internal("Database unavailable")
+    })?;
+
+    conn.transaction(|conn| {
+        Box::pin(async move {
+            const NONCE_START: i32 = 1;
+
+            let id: i32 = diesel::insert_into(useragent_client::table)
+                .values((
+                    useragent_client::public_key.eq(pubkey_bytes),
+                    useragent_client::nonce.eq(NONCE_START),
+                ))
+                .returning(useragent_client::id)
+                .get_result(conn)
+                .await
+                .map_err(|e| {
+                    error!(error = ?e, "Database error");
+                    Error::internal("Database operation failed")
+                })?;
+
+            let entity = UserAgentCredentials {
+                pubkey: pubkey.clone(),
+                nonce: NONCE_START,
+            };
+
+            integrity::sign_entity(conn, keyholder, &entity, id)
+                .await
+                .map_err(|e| {
+                    error!(error = ?e, "Failed to sign integrity tag for new user-agent key");
+                    Error::internal("Failed to register public key")
+                })?;
+
+            Result::<_, Error>::Ok(())
+        })
+    })
+    .await?;
+
+    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> {
+        verify_integrity(&self.conn.db, &self.conn.actors.key_holder, &pubkey).await?;
+
+        let nonce = create_nonce(&self.conn.db, &self.conn.actors.key_holder, &pubkey).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<authn::PublicKey, 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);
+        }
+
+        match token_ok {
+            true => {
+                register_key(&self.conn.db, &self.conn.actors.key_holder, &pubkey).await?;
+                self.transport
+                    .send(Ok(Outbound::AuthSuccess))
+                    .await
+                    .map_err(|_| Error::Transport)?;
+                Ok(pubkey)
+            }
+            false => {
+                error!("Invalid bootstrap token provided");
+                self.transport
+                    .send(Err(Error::InvalidBootstrapToken))
+                    .await
+                    .map_err(|_| Error::Transport)?;
+                Err(Error::InvalidBootstrapToken)
+            }
+        }
+    }
+
+    #[allow(missing_docs)]
+    #[allow(clippy::unused_unit)]
+    async fn verify_solution(
+        &mut self,
+        ChallengeContext {
+            challenge_nonce,
+            key,
+        }: &ChallengeContext,
+        ChallengeSolution { solution }: ChallengeSolution,
+    ) -> Result<authn::PublicKey, Self::Error> {
+        let signature = authn::Signature::try_from(solution.as_slice()).map_err(|_| {
+            error!("Failed to decode signature in challenge solution");
+            Error::InvalidChallengeSolution
+        })?;
+
+        let valid = key.verify(*challenge_nonce, USERAGENT_CONTEXT, &signature);
+
+        match valid {
+            true => {
+                self.transport
+                    .send(Ok(Outbound::AuthSuccess))
+                    .await
+                    .map_err(|_| Error::Transport)?;
+                Ok(key.clone())
+            }
+            false => {
+                self.transport
+                    .send(Err(Error::InvalidChallengeSolution))
+                    .await
+                    .map_err(|_| Error::Transport)?;
+                Err(Error::InvalidChallengeSolution)
+            }
+        }
+    }
+}

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

@@ -0,0 +1,40 @@
+use crate::{
+    actors::{GlobalActors, client::ClientProfile},
+    crypto::integrity::Integrable,
+    db,
+};
+use arbiter_crypto::authn;
+
+#[derive(Debug, arbiter_macros::Hashable)]
+pub struct UserAgentCredentials {
+    pub pubkey: authn::PublicKey,
+    pub nonce: i32,
+}
+
+impl Integrable for UserAgentCredentials {
+    const KIND: &'static str = "useragent_credentials";
+}
+
+// Messages, sent by user agent to connection client without having a request
+#[derive(Debug)]
+pub enum OutOfBand {
+    ClientConnectionRequest { profile: ClientProfile },
+    ClientConnectionCancel { pubkey: authn::PublicKey },
+}
+
+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

@@ -1,19 +1,21 @@
-use super::{OutOfBand, OperatorConnection};
-use crate::{
-    actors::{
-        flow_coordinator::client_connect_approval::ClientApprovalController,
-        operator_registry::ConnectOperator,
-    },
-    peers::client::ClientProfile,
-};
 use arbiter_crypto::authn;
-use arbiter_proto::transport::Sender;
 
-use kameo::{Actor, actor::ActorRef, messages};
 use std::{borrow::Cow, collections::HashMap};
+
+use arbiter_proto::transport::Sender;
+use async_trait::async_trait;
+use kameo::{Actor, actor::ActorRef, messages};
 use thiserror::Error;
 use tracing::error;
 
+use crate::actors::{
+    client::ClientProfile,
+    flow_coordinator::{RegisterUserAgent, client_connect_approval::ClientApprovalController},
+    user_agent::{OutOfBand, UserAgentConnection},
+};
+mod state;
+use state::{DummyContext, UserAgentEvents, UserAgentStateMachine};
+
 #[derive(Debug, Error)]
 pub enum Error {
     #[error("State transition failed")]
@@ -49,27 +51,53 @@ pub struct PendingClientApproval {
     controller: ActorRef<ClientApprovalController>,
 }
 
-pub struct OperatorSession {
+pub struct UserAgentSession {
-    props: OperatorConnection,
+    props: UserAgentConnection,
+    state: UserAgentStateMachine<DummyContext>,
     sender: Box<dyn Sender<OutOfBand>>,
 
     pending_client_approvals: HashMap<Vec<u8>, PendingClientApproval>,
 }
 
-pub mod handlers;
+pub mod connection;
 
-impl OperatorSession {
+impl UserAgentSession {
-    pub(crate) fn new(props: OperatorConnection, sender: Box<dyn Sender<OutOfBand>>) -> Self {
+    pub(crate) fn new(props: UserAgentConnection, sender: Box<dyn Sender<OutOfBand>>) -> Self {
         Self {
             props,
+            state: UserAgentStateMachine::new(DummyContext),
             sender,
             pending_client_approvals: Default::default(),
         }
     }
+
+    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 OperatorSession {
+impl UserAgentSession {
     #[message]
     pub async fn begin_new_client_approval(
         &mut self,
@@ -85,7 +113,7 @@ impl OperatorSession {
         {
             error!(
                 ?e,
-                actor = "operator",
+                actor = "user_agent",
                 event = "failed to announce new client connection"
             );
             return;
@@ -101,25 +129,28 @@ impl OperatorSession {
     }
 }
 
-impl Actor for OperatorSession {
+impl Actor for UserAgentSession {
     type Args = Self;
 
     type Error = Error;
 
-    async fn on_start(args: Self::Args, this: ActorRef<Self>) -> Result<Self, Self::Error> {
+    async fn on_start(
+        args: Self::Args,
+        this: kameo::prelude::ActorRef<Self>,
+    ) -> Result<Self, Self::Error> {
         args.props
             .actors
-            .operator_registry
+            .flow_coordinator
-            .ask(ConnectOperator {
+            .ask(RegisterUserAgent {
                 actor: this.clone(),
             })
             .await
             .map_err(|err| {
                 error!(
                     ?err,
-                    "Failed to register operator connection with operator registry"
+                    "Failed to register user agent connection with flow coordinator"
                 );
-                Error::internal("Failed to register operator connection with operator registry")
+                Error::internal("Failed to register user agent connection with flow coordinator")
             })?;
         Ok(args)
     }
@@ -149,7 +180,7 @@ impl Actor for OperatorSession {
             {
                 error!(
                     ?e,
-                    actor = "operator",
+                    actor = "user_agent",
                     event = "failed to announce client connection cancellation"
                 );
             }

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

@@ -0,0 +1,524 @@
+use std::sync::Mutex;
+
+use alloy::{consensus::TxEip1559, primitives::Address, signers::Signature};
+use arbiter_crypto::{
+    authn,
+    safecell::{SafeCell, SafeCellHandle as _},
+};
+use chacha20poly1305::{AeadInPlace, XChaCha20Poly1305, XNonce, aead::KeyInit};
+use diesel::{ExpressionMethods as _, QueryDsl as _, SelectableHelper};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use kameo::error::SendError;
+use kameo::messages;
+use kameo::prelude::Context;
+use tracing::{error, info};
+use x25519_dalek::{EphemeralSecret, PublicKey};
+
+use crate::actors::flow_coordinator::client_connect_approval::ClientApprovalAnswer;
+use crate::actors::keyholder::KeyHolderState;
+use crate::actors::user_agent::session::Error;
+use crate::actors::{
+    evm::{
+        ClientSignTransaction, Generate, ListWallets, SignTransactionError as EvmSignError,
+        UseragentCreateGrant, UseragentListGrants,
+    },
+    keyholder::{self, Bootstrap, TryUnseal},
+    user_agent::session::{
+        UserAgentSession,
+        state::{UnsealContext, UserAgentEvents, UserAgentStates},
+    },
+};
+use crate::db::models::{
+    EvmWalletAccess, NewEvmWalletAccess, ProgramClient, ProgramClientMetadata,
+};
+use crate::evm::policies::{Grant, SpecificGrant};
+
+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),
+}
+
+#[derive(Debug, Error)]
+pub enum SignTransactionError {
+    #[error("Policy evaluation failed")]
+    Vet(#[from] crate::evm::VetError),
+
+    #[error("Internal signing error")]
+    Internal,
+}
+
+#[derive(Debug, Error)]
+pub enum GrantMutationError {
+    #[error("Vault is sealed")]
+    VaultSealed,
+
+    #[error("Internal grant mutation error")]
+    Internal,
+}
+
+#[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<(i32, 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<(i32, 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,
+        basic: crate::evm::policies::SharedGrantSettings,
+        grant: crate::evm::policies::SpecificGrant,
+    ) -> Result<i32, GrantMutationError> {
+        match self
+            .props
+            .actors
+            .evm
+            .ask(UseragentCreateGrant { basic, grant })
+            .await
+        {
+            Ok(grant_id) => Ok(grant_id),
+            Err(err) => {
+                error!(?err, "EVM grant create failed");
+                Err(GrantMutationError::Internal)
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_grant_delete(
+        &mut self,
+        grant_id: i32,
+    ) -> Result<(), GrantMutationError> {
+        // match self
+        //     .props
+        //     .actors
+        //     .evm
+        //     .ask(UseragentDeleteGrant { grant_id })
+        //     .await
+        // {
+        //     Ok(()) => Ok(()),
+        //     Err(err) => {
+        //         error!(?err, "EVM grant delete failed");
+        //         Err(GrantMutationError::Internal)
+        //     }
+        // }
+       let _ = grant_id;
+        todo!()
+    }
+
+    #[message]
+    pub(crate) async fn handle_sign_transaction(
+        &mut self,
+        client_id: i32,
+        wallet_address: Address,
+        transaction: TxEip1559,
+    ) -> Result<Signature, SignTransactionError> {
+        match self
+            .props
+            .actors
+            .evm
+            .ask(ClientSignTransaction {
+                client_id,
+                wallet_address,
+                transaction,
+            })
+            .await
+        {
+            Ok(signature) => Ok(signature),
+            Err(SendError::HandlerError(EvmSignError::Vet(vet_error))) => {
+                Err(SignTransactionError::Vet(vet_error))
+            }
+            Err(err) => {
+                error!(?err, "EVM sign transaction failed in user-agent session");
+                Err(SignTransactionError::Internal)
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_grant_evm_wallet_access(
+        &mut self,
+        entries: Vec<NewEvmWalletAccess>,
+    ) -> Result<(), Error> {
+        let mut conn = self.props.db.get().await?;
+        conn.transaction(|conn| {
+            Box::pin(async move {
+                use crate::db::schema::evm_wallet_access;
+
+                for entry in entries {
+                    diesel::insert_into(evm_wallet_access::table)
+                        .values(&entry)
+                        .on_conflict_do_nothing()
+                        .execute(conn)
+                        .await?;
+                }
+
+                Result::<_, Error>::Ok(())
+            })
+        })
+        .await?;
+        Ok(())
+    }
+
+    #[message]
+    pub(crate) async fn handle_revoke_evm_wallet_access(
+        &mut self,
+        entries: Vec<i32>,
+    ) -> Result<(), Error> {
+        let mut conn = self.props.db.get().await?;
+        conn.transaction(|conn| {
+            Box::pin(async move {
+                use crate::db::schema::evm_wallet_access;
+                for entry in entries {
+                    diesel::delete(evm_wallet_access::table)
+                        .filter(evm_wallet_access::wallet_id.eq(entry))
+                        .execute(conn)
+                        .await?;
+                }
+
+                Result::<_, Error>::Ok(())
+            })
+        })
+        .await?;
+        Ok(())
+    }
+
+    #[message]
+    pub(crate) async fn handle_list_wallet_access(
+        &mut self,
+    ) -> Result<Vec<EvmWalletAccess>, Error> {
+        let mut conn = self.props.db.get().await?;
+        use crate::db::schema::evm_wallet_access;
+        let access_entries = evm_wallet_access::table
+            .select(EvmWalletAccess::as_select())
+            .load::<_>(&mut conn)
+            .await?;
+        Ok(access_entries)
+    }
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message(ctx)]
+    pub(crate) async fn handle_new_client_approve(
+        &mut self,
+        approved: bool,
+        pubkey: authn::PublicKey,
+        ctx: &mut Context<Self, Result<(), Error>>,
+    ) -> Result<(), Error> {
+        let pending_approval = match self.pending_client_approvals.remove(&pubkey.to_bytes()) {
+            Some(approval) => approval,
+            None => {
+                error!("Received client connection response for unknown client");
+                return Err(Error::internal("Unknown client in connection response"));
+            }
+        };
+
+        pending_approval
+            .controller
+            .tell(ClientApprovalAnswer { approved })
+            .await
+            .map_err(|err| {
+                error!(
+                    ?err,
+                    "Failed to send client approval response to controller"
+                );
+                Error::internal("Failed to send client approval response to controller")
+            })?;
+
+        ctx.actor_ref().unlink(&pending_approval.controller).await;
+
+        Ok(())
+    }
+
+    #[message]
+    pub(crate) async fn handle_sdk_client_list(
+        &mut self,
+    ) -> Result<Vec<(ProgramClient, ProgramClientMetadata)>, Error> {
+        use crate::db::schema::{client_metadata, program_client};
+        let mut conn = self.props.db.get().await?;
+
+        let clients = program_client::table
+            .inner_join(client_metadata::table)
+            .select((
+                ProgramClient::as_select(),
+                ProgramClientMetadata::as_select(),
+            ))
+            .load::<(ProgramClient, ProgramClientMetadata)>(&mut conn)
+            .await?;
+
+        Ok(clients)
+    }
+}

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

@@ -1,607 +0,0 @@
-use std::collections::HashMap;
-
-use crate::{
-    crypto::{
-        KeyCell, derive_key,
-        encryption::v1::{self, Nonce},
-        integrity::v1::HmacSha256,
-    },
-    db::{
-        self,
-        models::{self, OperatorId, OperatorIdentityId, RootKeyHistory, RootKeyHistoryId},
-        schema::{self},
-    },
-};
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
-use chrono::Utc;
-use diesel::{
-    ExpressionMethods as _, OptionalExtension, QueryDsl, SelectableHelper,
-    dsl::{count, insert_into, update},
-    select,
-};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use hmac::{KeyInit as _, Mac as _, digest::common};
-use kameo::{Actor, Reply, actor::ActorRef, messages};
-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,
-}
-
-#[derive(Debug, thiserror::Error)]
-pub enum UnsealError {}
-
-#[derive(Debug, thiserror::Error)]
-pub enum BootstrapError {
-    #[error("That operator already contributed his share")]
-    AlreadyContributed,
-}
-
-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,
-
-    Bootstrapping {
-        declared_operators: u64,
-        current_passphrases: HashMap<OperatorIdentityId, SafeCell<Vec<u8>>>,
-    },
-
-    Sealed {
-        threshold: u64, // basically, quorum size
-        root_key_history_id: RootKeyHistoryId,
-        current_shares: HashMap<OperatorId, SafeCell<Vec<u8>>>,
-    },
-    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) => {
-                    let operator_count: i64 = schema::operator::table
-                        .count()
-                        .get_result(&mut conn)
-                        .await?;
-                    State::Sealed {
-                        root_key_history_id: root_key_history.id,
-                        current_shares: HashMap::default(),
-                        threshold: shamir_threshold(operator_count.cast_unsigned()), // invariant: db couldn't return negative number of rows
-                    }
-                }
-                None => State::Unbootstrapped,
-            }
-        };
-
-        Ok(Self { db, state, events })
-    }
-
-    // Exclusive transaction to avoid race condtions 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::Bootstrapping { .. } => Err(Error::NotBootstrapped),
-            State::Unbootstrapped => Err(Error::NotBootstrapped),
-            State::Sealed { .. } => Err(Error::Sealed),
-        }
-    }
-
-    pub async fn finalize_bootstrap(&mut self) -> Result<(), Error> {
-        let State::Bootstrapping {
-            declared_operators,
-            current_passphrases,
-        } = &mut self.state
-        else {
-            return Err(Error::AlreadyBootstrapped);
-        };
-        let mut root_key = KeyCell::new_secure_random();
-        let root_key_salt = v1::generate_salt();
-
-        let mut seal_key = KeyCell::new_secure_random();
-
-        let shares = seal_key.0.read_inline(|seal_key| {
-            generate_shamir_shares(current_passphrases.len() as u64, seal_key.as_slice())
-        });
-
-        // Zero nonces are fine because they are one-time
-        let root_key_nonce = Nonce::default();
-        let data_encryption_nonce = 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 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| {
-                for ((operator_id, raw_passphrase), raw_share) in
-                    current_passphrases.iter_mut().zip(shares.iter())
-                {
-                    let salt = v1::generate_salt();
-                    let mut share_seal_key = derive_key(&mut raw_passphrase, &salt);
-                    let share_encryption_nonce = Nonce::default();
-
-                    let share_key = derive_key(&mut raw_passphrase, &salt);
-                }
-
-                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");
-        let _ = self.events.tell(Publish(events::Bootstrapped)).await;
-
-        Ok(())
-    }
-}
-
-// Seal / unseal / bootstrap stuff. Will be separated into another actor, eventually
-#[messages]
-impl Vault {
-    #[message]
-    pub async fn start_bootstrap(&mut self, declared_operators: u64) -> Result<(), Error> {
-        if !matches!(&self.state, State::Unbootstrapped) {
-            return Err(Error::AlreadyBootstrapped);
-        }
-
-        self.state = State::Bootstrapping {
-            declared_operators,
-            current_passphrases: HashMap::default(),
-        };
-        Ok(())
-    }
-
-    #[message]
-    pub async fn contribute_bootstrap(
-        &mut self,
-        operator: OperatorIdentityId,
-        key_raw: SafeCell<Vec<u8>>,
-    ) -> Result<(), Error> {
-        let State::Bootstrapping {
-            current_passphrases,
-            declared_operators,
-        } = &mut self.state
-        else {
-            return Err(Error::AlreadyBootstrapped);
-        };
-
-        if current_passphrases.contains_key(&operator) {
-            return Err(Error::AlreadyBootstrapped);
-        }
-        current_passphrases.insert(operator, key_raw);
-
-        if current_passphrases.len() == declared_operators {
-            return self.finalize_bootstrap(seal_key_raw);
-        }
-
-        Ok(())
-    }
-
-    #[message]
-    pub async fn contribute_unseal(
-        &mut self,
-        operator: OperatorId,
-        key_raw: SafeCell<Vec<u8>>,
-    ) -> Result<(), Error> {
-        let State::Sealed {
-            root_key_history_id,
-            current_shares,
-        } = &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(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 = derive_key(key_raw, &salt);
-
-        let mut root_key = SafeCell::new(current_key.ciphertext.clone());
-
-        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
-            })?;
-
-        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(Unsealed {
-            root_key_history_id: current_key.id,
-            root_key: KeyCell::try_from(root_key).map_err(|err| {
-                error!(?err, "Broken database: invalid encryption key size");
-                Error::BrokenDatabase
-            })?,
-        });
-
-        info!("Vault unsealed successfully");
-        let _ = self.events.tell(Publish(events::Unsealed)).await;
-
-        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,
-            current_shares: HashMap::new(),
-        };
-        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| match HmacSha256::new_from_slice(k) {
-                Ok(v) => v,
-                Err(_) => 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| match HmacSha256::new_from_slice(k) {
-                Ok(v) => v,
-                Err(_) => 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())
-    }
-}
-
-/// According to the spec, the quorum is 50% + 1
-/// with exception for 1 and 2 operators, those require exactly the number of operators registered
-fn shamir_threshold(comittee_size: u64) -> u64 {
-    if comittee_size == 2 || comittee_size == 1 {
-        return comittee_size;
-    }
-
-    let half_comittee = match comittee_size % 2 != 0 {
-        true => (comittee_size - 1) / 2,
-        false => comittee_size / 2,
-    };
-
-    half_comittee + 1
-}
-
-/// Beware: this function accepts raw key references (without memory protection)
-fn generate_shamir_shares(threshold: u64, key: &[u8]) -> Vec<SafeCell<Vec<u8>>> {
-    use vsss_rs::{shamir, *};
-
-    type P256Share = DefaultShare<IdentifierPrimeField<Scalar>, IdentifierPrimeField<Scalar>>;
-
-    let mut osrng = rand_core::OsRng::default();
-    let sk = SecretKey::random(&mut osrng);
-    let nzs = sk.to_nonzero_scalar();
-    let shared_secret = IdentifierPrimeField(*nzs.as_ref());
-    let res = shamir::split_secret::<P256Share>(2, 3, &shared_secret, &mut osrng);
-    assert!(res.is_ok());
-    let shares = res.unwrap();
-    let res = shares.combine();
-    assert!(res.is_ok());
-    let scalar = res.unwrap();
-    let nzs_dup = NonZeroScalar::from_repr(scalar.0.to_repr()).unwrap();
-    let sk_dup = SecretKey::from(nzs_dup);
-    assert_eq!(sk_dup.to_bytes(), sk.to_bytes());
-}
-
-#[cfg(test)]
-mod tests {
-    use crate::actors::GlobalActors;
-    use arbiter_crypto::safecell::SafeCellHandle as _;
-
-    use super::*;
-
-    async fn bootstrapped_actor(db: &db::DatabasePool) -> Vault {
-        let mut actor = Vault::new(db.clone(), GlobalActors::spawn_message_bus())
-            .await
-            .unwrap();
-        let seal_key = SafeCell::new(b"test-seal-key".to_vec());
-        actor.finalize_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(Unsealed {
-                root_key_history_id,
-                ..
-            }) => root_key_history_id,
-            _ => 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"
-        );
-    }
-}

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

@@ -1,12 +1,13 @@
+use std::sync::Arc;
+
+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)]
@@ -30,16 +31,16 @@ pub enum InitError {
     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 +49,7 @@ 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::{net::Ipv4Addr, string::FromUtf8Error};
+
+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 thiserror::Error;
+use tonic::transport::CertificateDer;
+
 use crate::db::{
     self,
     models::{NewTlsHistory, TlsHistory},
@@ -7,23 +21,10 @@ 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") {
+    let line_ending = match cfg!(target_family = "windows") {
-        pem::LineEnding::CRLF
+        true => pem::LineEnding::CRLF,
-    } else {
+        false => pem::LineEnding::LF,
-        pem::LineEnding::LF
     };
     pem::EncodeConfig::new().set_line_ending(line_ending)
 };
@@ -51,14 +52,11 @@ pub enum InitError {
 
 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(
+#[allow(unused)]
-    unused,
-    reason = "may be needed for future cert rotation implementation"
-)]
 struct SerializedTls {
     cert_pem: PemCert,
     cert_key_pem: String,
@@ -87,7 +85,7 @@ impl TlsCa {
 
         let cert_key_pem = certified_issuer.key().serialize_pem();
 
-        #[expect(
+        #[allow(
             clippy::unwrap_used,
             reason = "Broken cert couldn't bootstrap server anyway"
         )]
@@ -126,11 +124,7 @@ impl TlsCa {
         })
     }
 
-    #[expect(
+    #[allow(unused)]
-        unused,
-        clippy::unnecessary_wraps,
-        reason = "may be needed for future cert rotation implementation"
-    )]
     fn serialize(&self) -> Result<SerializedTls, InitError> {
         let cert_key_pem = self.issuer.key().serialize_pem();
         Ok(SerializedTls {
@@ -139,10 +133,7 @@ impl TlsCa {
         })
     }
 
-    #[expect(
+    #[allow(unused)]
-        unused,
-        reason = "may be needed for future cert rotation implementation"
-    )]
     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 +165,8 @@ 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 +177,17 @@ 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 +234,10 @@ 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/v1.rs

@@ -1,11 +1,12 @@
 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 ROOT_KEY_TAG: &[u8] = "arbiter/seal/v1".as_bytes();
-pub const TAG: &[u8] = b"arbiter/private-key/v1";
+pub const TAG: &[u8] = "arbiter/private-key/v1".as_bytes();
 
 pub const NONCE_LENGTH: usize = 24;
 
@@ -14,16 +15,14 @@ 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 self.0[i] == 0xFF {
-                if *byte == 0xFF {
+                self.0[i] = 0;
-                    *byte = 0;
             } else {
-                    *byte += 1;
+                self.0[i] += 1;
                 break;
             }
         }
     }
-    }
 
     pub fn to_vec(&self) -> Vec<u8> {
         self.0.to_vec()
@@ -46,20 +45,25 @@ pub type Salt = [u8; ArgonSalt::RECOMMENDED_LENGTH];
 
 pub fn generate_salt() -> Salt {
     let mut salt = Salt::default();
-    let mut rng =
+    #[allow(
-        StdRng::try_from_rng(&mut SysRng).expect("Rng failure is unrecoverable and should panic");
+        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
 }
 
 #[cfg(test)]
 mod tests {
+    use std::ops::Deref as _;
+
     use super::*;
     use crate::crypto::derive_key;
     use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
 
     #[test]
-    fn derive_seal_key_deterministic() {
+    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());
@@ -71,24 +75,25 @@ mod tests {
         let key1_reader = key1.0.read();
         let key2_reader = key2.0.read();
 
-        assert_eq!(&*key1_reader, &*key2_reader);
+        assert_eq!(key1_reader.deref(), key2_reader.deref());
     }
 
     #[test]
-    fn successful_derive() {
+    pub fn successful_derive() {
         static PASSWORD: &[u8] = b"password";
         let password = SafeCell::new(PASSWORD.to_vec());
         let salt = generate_salt();
 
         let mut key = derive_key(password, &salt);
         let key_reader = key.0.read();
+        let key_ref = key_reader.deref();
 
-        assert_ne!(key_reader.as_slice(), &[0u8; 32][..]);
+        assert_ne!(key_ref.as_slice(), &[0u8; 32][..]);
     }
 
     #[test]
     // We should fuzz this
-    pub fn nonce_increment() {
+    pub fn test_nonce_increment() {
         let mut nonce = Nonce([0u8; NONCE_LENGTH]);
         nonce.increment();
 

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

@@ -1,29 +1,32 @@
+use crate::actors::keyholder;
+use arbiter_crypto::hashing::Hashable;
+use hmac::Hmac;
+use sha2::Sha256;
+
+use diesel::{ExpressionMethods as _, QueryDsl, dsl::insert_into, sqlite::Sqlite};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use kameo::{actor::ActorRef, error::SendError};
+use sha2::Digest as _;
+
 use crate::{
-    actors::vault::{self, GetState, SignIntegrity, Vault, VerifyIntegrity},
+    actors::keyholder::{KeyHolder, SignIntegrity, VerifyIntegrity},
     db::{
         self,
         models::{IntegrityEnvelope, NewIntegrityEnvelope},
         schema::integrity_envelope,
     },
 };
-use arbiter_crypto::hashing::Hashable;
-
-use diesel::{ExpressionMethods as _, QueryDsl, dsl::insert_into, sqlite::Sqlite};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use hmac::Hmac;
-use kameo::{actor::ActorRef, error::SendError};
-use sha2::{Digest as _, Sha256};
 
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
     #[error("Database error: {0}")]
     Database(#[from] db::DatabaseError),
 
-    #[error("Vault error: {0}")]
+    #[error("KeyHolder error: {0}")]
-    Vault(#[from] vault::Error),
+    Keyholder(#[from] keyholder::Error),
 
-    #[error("Vault mailbox error")]
+    #[error("KeyHolder mailbox error")]
-    VaultSend,
+    KeyholderSend,
 
     #[error("Integrity envelope is missing for entity {entity_kind}")]
     MissingEnvelope { entity_kind: &'static str },
@@ -64,11 +67,6 @@ fn payload_hash(payload: &impl Hashable) -> [u8; 32] {
 }
 
 fn push_len_prefixed(out: &mut Vec<u8>, bytes: &[u8]) {
-    #[expect(
-        clippy::cast_possible_truncation,
-        clippy::as_conversions,
-        reason = "fixme! #85"
-    )]
     out.extend_from_slice(&(bytes.len() as u32).to_be_bytes());
     out.extend_from_slice(bytes);
 }
@@ -105,7 +103,7 @@ impl IntoId for &'_ [u8] {
 
 pub async fn sign_entity<E: Integrable>(
     conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    vault: &ActorRef<Vault>,
+    keyholder: &ActorRef<KeyHolder>,
     entity: &E,
     entity_id: impl IntoId,
 ) -> Result<(), Error> {
@@ -115,13 +113,12 @@ pub async fn sign_entity<E: Integrable>(
 
     let mac_input = build_mac_input(E::KIND, &entity_id, E::VERSION, &payload_hash);
 
-    let (key_version, mac) =
+    let (key_version, mac) = keyholder
-        vault
         .ask(SignIntegrity { mac_input })
         .await
         .map_err(|err| match err {
-                SendError::HandlerError(inner) => Error::Vault(inner),
+            kameo::error::SendError::HandlerError(inner) => Error::Keyholder(inner),
-                _ => Error::VaultSend,
+            _ => Error::KeyholderSend,
         })?;
 
     insert_into(integrity_envelope::table)
@@ -130,7 +127,7 @@ pub async fn sign_entity<E: Integrable>(
             entity_id,
             payload_version: E::VERSION,
             key_version,
-            mac: mac.clone(),
+            mac: mac.to_vec(),
         })
         .on_conflict((
             integrity_envelope::entity_id,
@@ -151,7 +148,7 @@ pub async fn sign_entity<E: Integrable>(
 
 pub async fn verify_entity<E: Integrable>(
     conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    vault: &ActorRef<Vault>,
+    keyholder: &ActorRef<KeyHolder>,
     entity: &E,
     entity_id: impl IntoId,
 ) -> Result<AttestationStatus, Error> {
@@ -179,7 +176,7 @@ pub async fn verify_entity<E: Integrable>(
     let payload_hash = payload_hash(&entity);
     let mac_input = build_mac_input(E::KIND, &entity_id, envelope.payload_version, &payload_hash);
 
-    let result = vault
+    let result = keyholder
         .ask(VerifyIntegrity {
             mac_input,
             expected_mac: envelope.mac,
@@ -192,14 +189,11 @@ pub async fn verify_entity<E: Integrable>(
         Ok(false) => Err(Error::MacMismatch {
             entity_kind: E::KIND,
         }),
-        Err(SendError::HandlerError(vault::Error::Sealed)) => Ok(AttestationStatus::Unavailable),
+        Err(SendError::HandlerError(keyholder::Error::NotBootstrapped)) => {
-        Err(_) => Err(Error::VaultSend),
+            Ok(AttestationStatus::Unavailable)
         }
+        Err(_) => Err(Error::KeyholderSend),
     }
-
-pub async fn is_signing_available(vault: &ActorRef<Vault>) -> Result<bool, Error> {
-    let state = vault.ask(GetState).await.map_err(|_| Error::VaultSend)?;
-    Ok(matches!(state, vault::VaultState::Unsealed))
 }
 
 #[cfg(test)]
@@ -209,10 +203,7 @@ mod tests {
     use kameo::{actor::ActorRef, prelude::Spawn};
 
     use crate::{
-        actors::{
+        actors::keyholder::{Bootstrap, KeyHolder},
-            GlobalActors,
-            vault::{Bootstrap, Vault},
-        },
         db::{self, schema},
     };
     use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
@@ -227,12 +218,8 @@ mod tests {
         const KIND: &'static str = "dummy_entity";
     }
 
-    async fn bootstrapped_vault(db: &db::DatabasePool) -> ActorRef<Vault> {
+    async fn bootstrapped_keyholder(db: &db::DatabasePool) -> ActorRef<KeyHolder> {
-        let actor = Vault::spawn(
+        let actor = KeyHolder::spawn(KeyHolder::new(db.clone()).await.unwrap());
-            Vault::new(db.clone(), GlobalActors::spawn_message_bus())
-                .await
-                .unwrap(),
-        );
         actor
             .ask(Bootstrap {
                 seal_key_raw: SafeCell::new(b"integrity-test-seal-key".to_vec()),
@@ -244,18 +231,18 @@ mod tests {
 
     #[tokio::test]
     async fn sign_writes_envelope_and_verify_passes() {
-        const ENTITY_ID: &[u8] = b"entity-id-7";
-
         let db = db::create_test_pool().await;
-        let vault = bootstrapped_vault(&db).await;
+        let keyholder = bootstrapped_keyholder(&db).await;
         let mut conn = db.get().await.unwrap();
 
+        const ENTITY_ID: &[u8] = b"entity-id-7";
+
         let entity = DummyEntity {
             payload_version: 1,
             payload: b"payload-v1".to_vec(),
         };
 
-        sign_entity(&mut conn, &vault, &entity, ENTITY_ID)
+        sign_entity(&mut conn, &keyholder, &entity, ENTITY_ID)
             .await
             .unwrap();
 
@@ -268,25 +255,25 @@ mod tests {
             .unwrap();
 
         assert_eq!(count, 1, "envelope row must be created exactly once");
-        verify_entity(&mut conn, &vault, &entity, ENTITY_ID)
+        verify_entity(&mut conn, &keyholder, &entity, ENTITY_ID)
             .await
             .unwrap();
     }
 
     #[tokio::test]
     async fn tampered_mac_fails_verification() {
-        const ENTITY_ID: &[u8] = b"entity-id-11";
-
         let db = db::create_test_pool().await;
-        let vault = bootstrapped_vault(&db).await;
+        let keyholder = bootstrapped_keyholder(&db).await;
         let mut conn = db.get().await.unwrap();
 
+        const ENTITY_ID: &[u8] = b"entity-id-11";
+
         let entity = DummyEntity {
             payload_version: 1,
             payload: b"payload-v1".to_vec(),
         };
 
-        sign_entity(&mut conn, &vault, &entity, ENTITY_ID)
+        sign_entity(&mut conn, &keyholder, &entity, ENTITY_ID)
             .await
             .unwrap();
 
@@ -298,7 +285,7 @@ mod tests {
             .await
             .unwrap();
 
-        let err = verify_entity(&mut conn, &vault, &entity, ENTITY_ID)
+        let err = verify_entity(&mut conn, &keyholder, &entity, ENTITY_ID)
             .await
             .unwrap_err();
         assert!(matches!(err, Error::MacMismatch { .. }));
@@ -306,18 +293,18 @@ mod tests {
 
     #[tokio::test]
     async fn changed_payload_fails_verification() {
-        const ENTITY_ID: &[u8] = b"entity-id-21";
-
         let db = db::create_test_pool().await;
-        let vault = bootstrapped_vault(&db).await;
+        let keyholder = bootstrapped_keyholder(&db).await;
         let mut conn = db.get().await.unwrap();
 
+        const ENTITY_ID: &[u8] = b"entity-id-21";
+
         let entity = DummyEntity {
             payload_version: 1,
             payload: b"payload-v1".to_vec(),
         };
 
-        sign_entity(&mut conn, &vault, &entity, ENTITY_ID)
+        sign_entity(&mut conn, &keyholder, &entity, ENTITY_ID)
             .await
             .unwrap();
 
@@ -326,7 +313,7 @@ mod tests {
             ..entity
         };
 
-        let err = verify_entity(&mut conn, &vault, &tampered, ENTITY_ID)
+        let err = verify_entity(&mut conn, &keyholder, &tampered, ENTITY_ID)
             .await
             .unwrap_err();
         assert!(matches!(err, Error::MacMismatch { .. }));

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

@@ -1,5 +1,4 @@
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
+use std::ops::Deref as _;
-use encryption::v1::{Nonce, Salt};
 
 use argon2::{Algorithm, Argon2};
 use chacha20poly1305::{
@@ -11,9 +10,13 @@ use rand::{
     rngs::{StdRng, SysRng},
 };
 
+use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
+
 pub mod encryption;
 pub mod integrity;
 
+use encryption::v1::{Nonce, Salt};
+
 pub struct KeyCell(pub SafeCell<Key>);
 impl From<SafeCell<Key>> for KeyCell {
     fn from(value: SafeCell<Key>) -> Self {
@@ -28,7 +31,7 @@ impl TryFrom<SafeCell<Vec<u8>>> for KeyCell {
         if value.len() != size_of::<Key>() {
             return Err(());
         }
-        let cell = SafeCell::new_inline_default(|cell_write: &mut Key| {
+        let cell = SafeCell::new_inline(|cell_write: &mut Key| {
             cell_write.copy_from_slice(&value);
         });
         Ok(Self(cell))
@@ -37,9 +40,12 @@ impl TryFrom<SafeCell<Vec<u8>>> for KeyCell {
 
 impl KeyCell {
     pub fn new_secure_random() -> Self {
-        let key = SafeCell::new_inline_default(|key_buffer: &mut Key| {
+        let key = SafeCell::new_inline(|key_buffer: &mut Key| {
-            let mut rng = StdRng::try_from_rng(&mut SysRng)
+            #[allow(
-                .expect("Rng failure is unrecoverable and should panic");
+                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);
         });
 
@@ -53,7 +59,8 @@ impl KeyCell {
         mut buffer: impl AsMut<Vec<u8>>,
     ) -> Result<(), Error> {
         let key_reader = self.0.read();
-        let cipher = XChaCha20Poly1305::new(&key_reader);
+        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)
@@ -65,7 +72,8 @@ impl KeyCell {
         buffer: &mut SafeCell<Vec<u8>>,
     ) -> Result<(), Error> {
         let key_reader = self.0.read();
-        let cipher = XChaCha20Poly1305::new(&key_reader);
+        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();
@@ -79,7 +87,8 @@ impl KeyCell {
         plaintext: impl AsRef<[u8]>,
     ) -> Result<Vec<u8>, Error> {
         let key_reader = self.0.read();
-        let mut cipher = XChaCha20Poly1305::new(&key_reader);
+        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(
@@ -94,7 +103,7 @@ impl KeyCell {
 }
 
 /// Derive a fixed-length key from the password using Argon2id, which is designed for password hashing and key derivation.
-pub fn derive_key(password: &mut SafeCell<Vec<u8>>, salt: &Salt) -> KeyCell {
+pub fn derive_key(mut password: SafeCell<Vec<u8>>, salt: &Salt) -> KeyCell {
     let params = {
         #[cfg(debug_assertions)]
         {
@@ -107,15 +116,20 @@ pub fn derive_key(password: &mut SafeCell<Vec<u8>>, salt: &Salt) -> KeyCell {
         }
     };
 
+    #[allow(clippy::unwrap_used)]
     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, salt, key_buffer)
+            .hash_password_into(password_source.deref(), salt, key_buffer)
-            .expect("Better fail completely than return a weak key");
+            .unwrap();
     });
 
     key.into()
@@ -130,7 +144,7 @@ mod tests {
     use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
 
     #[test]
-    fn encrypt_decrypt() {
+    pub fn encrypt_decrypt() {
         static PASSWORD: &[u8] = b"password";
         let password = SafeCell::new(PASSWORD.to_vec());
         let salt = generate_salt();

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

@@ -5,6 +5,7 @@ use diesel_async::{
     sync_connection_wrapper::SyncConnectionWrapper,
 };
 use diesel_migrations::{EmbeddedMigrations, MigrationHarness, embed_migrations};
+
 use thiserror::Error;
 use tracing::info;
 
@@ -22,14 +23,14 @@ const MIGRATIONS: EmbeddedMigrations = embed_migrations!("migrations");
 
 #[derive(Error, Debug)]
 pub enum DatabaseSetupError {
-    #[error(transparent)]
+    #[error("Failed to determine home directory")]
-    ConcurrencySetup(diesel::result::Error),
+    HomeDir(std::io::Error),
 
     #[error(transparent)]
     Connection(diesel::ConnectionError),
 
-    #[error("Failed to determine home directory")]
+    #[error(transparent)]
-    HomeDir(std::io::Error),
+    ConcurrencySetup(diesel::result::Error),
 
     #[error(transparent)]
     Migration(Box<dyn std::error::Error + Send + Sync>),
@@ -40,11 +41,10 @@ pub enum DatabaseSetupError {
 
 #[derive(Error, Debug)]
 pub enum DatabaseError {
-    #[error("Database query error")]
-    Connection(#[from] diesel::result::Error),
-
     #[error("Database connection error")]
     Pool(#[from] PoolError),
+    #[error("Database query error")]
+    Connection(#[from] diesel::result::Error),
 }
 
 #[tracing::instrument(level = "info")]
@@ -93,16 +93,13 @@ fn initialize_database(url: &str) -> Result<(), DatabaseSetupError> {
 }
 
 #[tracing::instrument(level = "info")]
-/// Creates a connection pool for the `SQLite` database.
-///
-/// # Panics
-/// Panics if the database path is not valid UTF-8.
 pub async fn create_pool(url: Option<&str>) -> Result<DatabasePool, DatabaseSetupError> {
     let database_url = url.map(String::from).unwrap_or(
+        #[allow(clippy::expect_used)]
         database_path()?
             .to_str()
             .expect("database path is not valid UTF-8")
-            .to_owned(),
+            .to_string(),
     );
 
     initialize_database(&database_url)?;
@@ -137,19 +134,19 @@ pub async fn create_pool(url: Option<&str>) -> Result<DatabasePool, DatabaseSetu
 }
 
 #[mutants::skip]
-#[expect(clippy::missing_panics_doc, reason = "Tests oriented function")]
-/// Creates a test database pool with a temporary `SQLite` database file.
 pub async fn create_test_pool() -> DatabasePool {
     use rand::distr::{Alphanumeric, SampleString as _};
 
     let tempfile_name = Alphanumeric.sample_string(&mut rand::rng(), 16);
 
     let file = std::env::temp_dir().join(tempfile_name);
+    #[allow(clippy::expect_used)]
     let url = file
         .to_str()
         .expect("temp file path is not valid UTF-8")
-        .to_owned();
+        .to_string();
 
+    #[allow(clippy::expect_used)]
     create_pool(Some(&url))
         .await
         .expect("Failed to create test database pool")

server/crates/arbiter-server/src/db/models.rs

@@ -1,14 +1,13 @@
-#![allow(
+#![allow(unused)]
-    clippy::duplicated_attributes,
+#![allow(clippy::all)]
-    reason = "restructed's #[view] causes false positives"
+
-)]
 use crate::db::schema::{
     self, aead_encrypted, arbiter_settings, evm_basic_grant, evm_ether_transfer_grant,
     evm_ether_transfer_grant_target, evm_ether_transfer_limit, evm_token_transfer_grant,
     evm_token_transfer_log, evm_token_transfer_volume_limit, evm_transaction_log, evm_wallet,
     integrity_envelope, root_key_history, tls_history,
 };
-
+use chrono::{DateTime, Utc};
 use diesel::{prelude::*, sqlite::Sqlite};
 use restructed::Models;
 
@@ -28,16 +27,16 @@ pub mod types {
     pub struct SqliteTimestamp(pub DateTime<Utc>);
     impl SqliteTimestamp {
         pub fn now() -> Self {
-            Self(Utc::now())
+            SqliteTimestamp(Utc::now())
         }
     }
 
-    impl From<DateTime<Utc>> for SqliteTimestamp {
+    impl From<chrono::DateTime<Utc>> for SqliteTimestamp {
-        fn from(dt: DateTime<Utc>) -> Self {
+        fn from(dt: chrono::DateTime<Utc>) -> Self {
-            Self(dt)
+            SqliteTimestamp(dt)
         }
     }
-    impl From<SqliteTimestamp> for DateTime<Utc> {
+    impl From<SqliteTimestamp> for chrono::DateTime<Utc> {
         fn from(ts: SqliteTimestamp) -> Self {
             ts.0
         }
@@ -48,11 +47,6 @@ pub mod types {
             &'b self,
             out: &mut diesel::serialize::Output<'b, '_, Sqlite>,
         ) -> diesel::serialize::Result {
-            #[expect(
-                clippy::cast_possible_truncation,
-                clippy::as_conversions,
-                reason = "fixme! #84; this will break up in 2038 :3"
-            )]
             let unix_timestamp = self.0.timestamp() as i32;
             out.set_value(unix_timestamp);
             Ok(IsNull::No)
@@ -75,72 +69,9 @@ pub mod types {
             let datetime =
                 DateTime::from_timestamp(unix_timestamp, 0).ok_or("Timestamp is out of bounds")?;
 
-            Ok(Self(datetime))
+            Ok(SqliteTimestamp(datetime))
         }
     }
-
-    macro_rules! declare_id {
-        ($name:ident) => {
-            #[derive(Debug, FromSqlRow, AsExpression, Clone, Hash, Copy, PartialEq, Eq)]
-            #[diesel(sql_type = Integer)]
-            #[repr(transparent)] // hint compiler to optimize the wrapper struct away
-            pub struct $name(i32);
-
-            impl $name {
-                pub const fn to_raw(self) -> i32 {
-                    self.0
-                }
-                pub const fn from_raw(raw: i32) -> Self {
-                    Self(raw)
-                }
-            }
-
-            impl FromSql<Integer, Sqlite> for $name {
-                fn from_sql(
-                    bytes: <Sqlite as diesel::backend::Backend>::RawValue<'_>,
-                ) -> diesel::deserialize::Result<Self> {
-                    FromSql::<Integer, Sqlite>::from_sql(bytes).map(Self)
-                }
-            }
-            impl ToSql<Integer, Sqlite> for $name {
-                fn to_sql<'b>(
-                    &'b self,
-                    out: &mut diesel::serialize::Output<'b, '_, Sqlite>,
-                ) -> diesel::serialize::Result {
-                    ToSql::<Integer, Sqlite>::to_sql(&self.0, out)
-                }
-            }
-        };
-    }
-
-    declare_id!(ChainId);
-
-    #[expect(
-        clippy::cast_sign_loss,
-        clippy::cast_possible_truncation,
-        clippy::as_conversions,
-        reason = "safe because chain_id is stored as i32 but is guaranteed to be a valid ChainId by the API when creating grants"
-    )]
-    const _: () = {
-        impl From<ChainId> for alloy::primitives::ChainId {
-            fn from(chain_id: ChainId) -> Self {
-                chain_id.0 as Self
-            }
-        }
-        impl From<alloy::primitives::ChainId> for ChainId {
-            fn from(chain_id: alloy::primitives::ChainId) -> Self {
-                Self(chain_id as _)
-            }
-        }
-    };
-
-    declare_id!(OperatorId);
-    declare_id!(OperatorIdentityId);
-    declare_id!(AeadEncryptedId);
-    declare_id!(RootKeyHistoryId);
-    declare_id!(TlsHistoryId);
-    declare_id!(EvmWalletId);
-    declare_id!(ClientId);
 }
 pub use types::*;
 
@@ -153,12 +84,12 @@ pub use types::*;
 )]
 #[diesel(table_name = aead_encrypted, check_for_backend(Sqlite))]
 pub struct AeadEncrypted {
-    pub id: AeadEncryptedId,
+    pub id: i32,
     pub ciphertext: Vec<u8>,
     pub tag: Vec<u8>,
     pub current_nonce: Vec<u8>,
     pub schema_version: i32,
-    pub associated_root_key_id: RootKeyHistoryId,
+    pub associated_root_key_id: i32, // references root_key_history.id
     pub created_at: SqliteTimestamp,
 }
 
@@ -171,7 +102,7 @@ pub struct AeadEncrypted {
     attributes_with = "deriveless"
 )]
 pub struct RootKeyHistory {
-    pub id: RootKeyHistoryId,
+    pub id: i32,
     pub ciphertext: Vec<u8>,
     pub tag: Vec<u8>,
     pub root_key_encryption_nonce: Vec<u8>,
@@ -189,7 +120,7 @@ pub struct RootKeyHistory {
     attributes_with = "deriveless"
 )]
 pub struct TlsHistory {
-    pub id: TlsHistoryId,
+    pub id: i32,
     pub cert: String,
     pub cert_key: String, // PEM Encoded private key
     pub ca_cert: String,  // PEM Encoded certificate for cert signing
@@ -214,7 +145,7 @@ pub struct ArbiterSettings {
     attributes_with = "deriveless"
 )]
 pub struct EvmWallet {
-    pub id: EvmWalletId,
+    pub id: i32,
     pub address: Vec<u8>,
     pub aead_encrypted_id: i32,
     pub created_at: SqliteTimestamp,
@@ -236,7 +167,7 @@ pub struct EvmWallet {
 )]
 pub struct EvmWalletAccess {
     pub id: i32,
-    pub wallet_id: EvmWalletId,
+    pub wallet_id: i32,
     pub client_id: i32,
     pub created_at: SqliteTimestamp,
 }
@@ -263,7 +194,8 @@ pub struct ProgramClientMetadataHistory {
 #[derive(Models, Queryable, Debug, Insertable, Selectable)]
 #[diesel(table_name = schema::program_client, check_for_backend(Sqlite))]
 pub struct ProgramClient {
-    pub id: ClientId,
+    pub id: i32,
+    pub nonce: i32,
     pub public_key: Vec<u8>,
     pub metadata_id: i32,
     pub created_at: SqliteTimestamp,
@@ -271,24 +203,15 @@ pub struct ProgramClient {
 }
 
 #[derive(Queryable, Debug)]
-#[diesel(table_name = schema::operator_client, check_for_backend(Sqlite))]
+#[diesel(table_name = schema::useragent_client, check_for_backend(Sqlite))]
-pub struct OperatorClient {
+pub struct UseragentClient {
-    pub id: OperatorIdentityId,
+    pub id: i32,
+    pub nonce: i32,
     pub public_key: Vec<u8>,
     pub created_at: SqliteTimestamp,
     pub updated_at: SqliteTimestamp,
 }
 
-#[derive(Queryable, Debug)]
-#[diesel(table_name = schema::operator, check_for_backend(Sqlite))]
-pub struct Operator {
-    pub id: OperatorId,
-    pub share: Vec<u8>,
-    pub share_nonce: Vec<u8>,
-    pub created_at: SqliteTimestamp,
-    pub updated_at: SqliteTimestamp,
-}
-
 #[derive(Models, Queryable, Debug, Insertable, Selectable)]
 #[diesel(table_name = evm_ether_transfer_limit, check_for_backend(Sqlite))]
 #[view(
@@ -314,7 +237,7 @@ pub struct EvmEtherTransferLimit {
 pub struct EvmBasicGrant {
     pub id: i32,
     pub wallet_access_id: i32, // references evm_wallet_access.id
-    pub chain_id: ChainId,
+    pub chain_id: i32,
     pub valid_from: Option<SqliteTimestamp>,
     pub valid_until: Option<SqliteTimestamp>,
     pub max_gas_fee_per_gas: Option<Vec<u8>>,
@@ -337,7 +260,7 @@ pub struct EvmTransactionLog {
     pub id: i32,
     pub grant_id: i32,
     pub wallet_access_id: i32,
-    pub chain_id: ChainId,
+    pub chain_id: i32,
     pub eth_value: Vec<u8>,
     pub signed_at: SqliteTimestamp,
 }
@@ -412,7 +335,7 @@ pub struct EvmTokenTransferLog {
     pub id: i32,
     pub grant_id: i32,
     pub log_id: i32,
-    pub chain_id: ChainId,
+    pub chain_id: i32,
     pub token_contract: Vec<u8>,
     pub recipient_address: Vec<u8>,
     pub value: Vec<u8>,
@@ -432,7 +355,7 @@ pub struct IntegrityEnvelope {
     pub entity_kind: String,
     pub entity_id: Vec<u8>,
     pub payload_version: i32,
-    pub key_version: RootKeyHistoryId,
+    pub key_version: i32,
     pub mac: Vec<u8>,
     pub signed_at: SqliteTimestamp,
     pub created_at: SqliteTimestamp,

server/crates/arbiter-server/src/db/schema.rs

@@ -152,28 +152,10 @@ diesel::table! {
     }
 }
 
-diesel::table! {
-    operator (id) {
-        id -> Nullable<Integer>,
-        share -> Binary,
-        share_nonce -> Binary,
-        created_at -> Integer,
-        updated_at -> Integer,
-    }
-}
-
-diesel::table! {
-    operator_identity (id) {
-        id -> Integer,
-        public_key -> Binary,
-        created_at -> Integer,
-        updated_at -> Integer,
-    }
-}
-
 diesel::table! {
     program_client (id) {
         id -> Integer,
+        nonce -> Integer,
         public_key -> Binary,
         metadata_id -> Integer,
         created_at -> Integer,
@@ -204,6 +186,17 @@ diesel::table! {
     }
 }
 
+diesel::table! {
+    useragent_client (id) {
+        id -> Integer,
+        nonce -> Integer,
+        public_key -> Binary,
+        key_type -> Integer,
+        created_at -> Integer,
+        updated_at -> Integer,
+    }
+}
+
 diesel::joinable!(aead_encrypted -> root_key_history (associated_root_key_id));
 diesel::joinable!(arbiter_settings -> root_key_history (root_key_id));
 diesel::joinable!(arbiter_settings -> tls_history (tls_id));
@@ -222,7 +215,6 @@ diesel::joinable!(evm_transaction_log -> evm_wallet_access (wallet_access_id));
 diesel::joinable!(evm_wallet -> aead_encrypted (aead_encrypted_id));
 diesel::joinable!(evm_wallet_access -> evm_wallet (wallet_id));
 diesel::joinable!(evm_wallet_access -> program_client (client_id));
-diesel::joinable!(operator -> operator_identity (id));
 diesel::joinable!(program_client -> client_metadata (metadata_id));
 
 diesel::allow_tables_to_appear_in_same_query!(
@@ -241,9 +233,8 @@ diesel::allow_tables_to_appear_in_same_query!(
     evm_wallet,
     evm_wallet_access,
     integrity_envelope,
-    operator,
-    operator_identity,
     program_client,
     root_key_history,
     tls_history,
+    useragent_client,
 );

server/crates/arbiter-server/src/evm/abi.rs

@@ -45,7 +45,7 @@ sol! {
 
 sol! {
     /// Permit2 — Uniswap's canonical token approval manager.
-    /// Replaces per-contract ERC-20 `approve()` with a single approval hub.
+    /// Replaces per-contract ERC-20 approve() with a single approval hub.
     #[derive(Debug)]
     interface IPermit2 {
         struct TokenPermissions {

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

@@ -1,5 +1,17 @@
+pub mod abi;
+pub mod safe_signer;
+
+use alloy::{
+    consensus::TxEip1559,
+    primitives::{TxKind, U256},
+};
+use chrono::Utc;
+use diesel::{ExpressionMethods as _, QueryDsl as _, QueryResult, insert_into, sqlite::Sqlite};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use kameo::actor::ActorRef;
+
 use crate::{
-    actors::vault::Vault,
+    actors::keyholder::KeyHolder,
     crypto::integrity,
     db::{
         self, DatabaseError,
@@ -15,18 +27,6 @@ use crate::{
     },
 };
 
-use alloy::{
-    consensus::TxEip1559,
-    primitives::{TxKind, U256},
-};
-use chrono::Utc;
-use diesel::{ExpressionMethods as _, QueryDsl as _, QueryResult, insert_into, sqlite::Sqlite};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use kameo::actor::ActorRef;
-
-pub mod abi;
-pub mod safe_signer;
-
 pub mod policies;
 mod utils;
 
@@ -34,7 +34,7 @@ mod utils;
 #[derive(Debug, thiserror::Error)]
 pub enum PolicyError {
     #[error("Database error")]
-    Database(#[from] DatabaseError),
+    Database(#[from] crate::db::DatabaseError),
     #[error("Transaction violates policy: {0:?}")]
     Violations(Vec<EvalViolation>),
     #[error("No matching grant found")]
@@ -66,7 +66,7 @@ pub enum AnalyzeError {
 #[derive(Debug, thiserror::Error)]
 pub enum ListError {
     #[error("Database error")]
-    Database(#[from] DatabaseError),
+    Database(#[from] crate::db::DatabaseError),
 
     #[error("Integrity verification failed for grant")]
     Integrity(#[from] integrity::Error),
@@ -127,7 +127,7 @@ async fn check_shared_constraints(
             .get_result(conn)
             .await?;
 
-        if count >= rate_limit.count.into() {
+        if count >= rate_limit.count as i64 {
             violations.push(EvalViolation::RateLimitExceeded);
         }
     }
@@ -138,7 +138,7 @@ async fn check_shared_constraints(
 // Supporting only EIP-1559 transactions for now, but we can easily extend this to support legacy transactions if needed
 pub struct Engine {
     db: db::DatabasePool,
-    vault: ActorRef<Vault>,
+    keyholder: ActorRef<KeyHolder>,
 }
 
 impl Engine {
@@ -158,7 +158,7 @@ impl Engine {
             .map_err(DatabaseError::from)?
             .ok_or(PolicyError::NoMatchingGrant)?;
 
-        integrity::verify_entity(&mut conn, &self.vault, &grant.settings, grant.id).await?;
+        integrity::verify_entity(&mut conn, &self.keyholder, &grant.settings, grant.id).await?;
 
         let mut violations = check_shared_constraints(
             &context,
@@ -179,23 +179,25 @@ impl Engine {
         }
 
         if run_kind == RunKind::Execution {
-            conn.transaction(async |conn| {
+            conn.transaction(|conn| {
+                Box::pin(async move {
                     let log_id: i32 = insert_into(evm_transaction_log::table)
                         .values(&NewEvmTransactionLog {
                             grant_id: grant.common_settings_id,
                             wallet_access_id: context.target.id,
-                        chain_id: context.chain.into(),
+                            chain_id: context.chain as i32,
                             eth_value: utils::u256_to_bytes(context.value).to_vec(),
                             signed_at: Utc::now().into(),
                         })
                         .returning(evm_transaction_log::id)
-                    .get_result(&mut *conn)
+                        .get_result(conn)
                         .await?;
 
-                P::record_transaction(&context, meaning, log_id, &grant, &mut *conn).await?;
+                    P::record_transaction(&context, meaning, log_id, &grant, conn).await?;
 
                     QueryResult::Ok(())
                 })
+            })
             .await
             .map_err(DatabaseError::from)?;
         }
@@ -205,8 +207,8 @@ impl Engine {
 }
 
 impl Engine {
-    pub const fn new(db: db::DatabasePool, vault: ActorRef<Vault>) -> Self {
+    pub fn new(db: db::DatabasePool, keyholder: ActorRef<KeyHolder>) -> Self {
-        Self { db, vault }
+        Self { db, keyholder }
     }
 
     pub async fn create_grant<P: Policy>(
@@ -217,21 +219,16 @@ impl Engine {
         P::Settings: Clone,
     {
         let mut conn = self.db.get().await?;
-        let vault = self.vault.clone();
+        let keyholder = self.keyholder.clone();
 
         let id = conn
-            .transaction(async |conn| {
+            .transaction(|conn| {
+                Box::pin(async move {
                     use schema::evm_basic_grant;
 
-                #[expect(
-                    clippy::cast_possible_truncation,
-                    clippy::cast_possible_wrap,
-                    clippy::as_conversions,
-                    reason = "fixme! #86"
-                )]
                     let basic_grant: EvmBasicGrant = insert_into(evm_basic_grant::table)
                         .values(&NewEvmBasicGrant {
-                        chain_id: full_grant.shared.chain.into(),
+                            chain_id: full_grant.shared.chain as i32,
                             wallet_access_id: full_grant.shared.wallet_access_id,
                             valid_from: full_grant.shared.valid_from.map(SqliteTimestamp),
                             valid_until: full_grant.shared.valid_until.map(SqliteTimestamp),
@@ -256,17 +253,18 @@ impl Engine {
                             revoked_at: None,
                         })
                         .returning(evm_basic_grant::all_columns)
-                    .get_result(&mut *conn)
+                        .get_result(conn)
                         .await?;
 
-                P::create_grant(&basic_grant, &full_grant.specific, &mut *conn).await?;
+                    P::create_grant(&basic_grant, &full_grant.specific, conn).await?;
 
-                integrity::sign_entity(&mut *conn, &vault, &full_grant, basic_grant.id)
+                    integrity::sign_entity(conn, &keyholder, &full_grant, basic_grant.id)
                         .await
                         .map_err(|_| diesel::result::Error::RollbackTransaction)?;
 
                     QueryResult::Ok(basic_grant.id)
                 })
+            })
             .await?;
 
         Ok(id)
@@ -285,7 +283,7 @@ impl Engine {
 
         // Verify integrity of all grants before returning any results
         for grant in &all_grants {
-            integrity::verify_entity(conn, &self.vault, &grant.settings, grant.id).await?;
+            integrity::verify_entity(conn, &self.keyholder, &grant.settings, grant.id).await?;
         }
 
         Ok(all_grants.into_iter().map(|g| Grant {
@@ -315,7 +313,7 @@ impl Engine {
         let TxKind::Call(to) = transaction.to else {
             return Err(VetError::ContractCreationNotSupported);
         };
-        let context = EvalContext {
+        let context = policies::EvalContext {
             target,
             chain: transaction.chain_id,
             to,
@@ -359,8 +357,7 @@ mod tests {
     use crate::db::{
         self, DatabaseConnection,
         models::{
-            EvmBasicGrant, EvmWalletAccess, EvmWalletId, NewEvmBasicGrant, NewEvmTransactionLog,
+            EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, NewEvmTransactionLog, SqliteTimestamp,
-            SqliteTimestamp,
         },
         schema::{evm_basic_grant, evm_transaction_log},
     };
@@ -378,7 +375,7 @@ mod tests {
         EvalContext {
             target: EvmWalletAccess {
                 id: WALLET_ACCESS_ID,
-                wallet_id: EvmWalletId::from_raw(5),
+                wallet_id: 10,
                 client_id: 20,
                 created_at: SqliteTimestamp(Utc::now()),
             },
@@ -397,6 +394,7 @@ mod tests {
             chain: CHAIN_ID,
             valid_from: None,
             valid_until: None,
+            revoked_at: None,
             max_gas_fee_per_gas: None,
             max_priority_fee_per_gas: None,
             rate_limit: None,
@@ -407,16 +405,10 @@ mod tests {
         conn: &mut DatabaseConnection,
         shared: &SharedGrantSettings,
     ) -> EvmBasicGrant {
-        #[expect(
-            clippy::cast_possible_truncation,
-            clippy::cast_possible_wrap,
-            clippy::as_conversions,
-            reason = "fixme! #86"
-        )]
         insert_into(evm_basic_grant::table)
             .values(NewEvmBasicGrant {
                 wallet_access_id: shared.wallet_access_id,
-                chain_id: shared.chain.into(),
+                chain_id: shared.chain as i32,
                 valid_from: shared.valid_from.map(SqliteTimestamp),
                 valid_until: shared.valid_until.map(SqliteTimestamp),
                 max_gas_fee_per_gas: shared
@@ -580,7 +572,7 @@ mod tests {
             .values(NewEvmTransactionLog {
                 grant_id: basic_grant.id,
                 wallet_access_id: WALLET_ACCESS_ID,
-                chain_id: CHAIN_ID.into(),
+                chain_id: CHAIN_ID as i32,
                 eth_value: super::utils::u256_to_bytes(U256::ZERO).to_vec(),
                 signed_at: SqliteTimestamp(Utc::now()),
             })
@@ -605,4 +597,24 @@ mod tests {
             assert!(violations.is_empty());
         }
     }
+
+    #[test]
+    fn shared_settings_hash_changes_when_revoked_at_changes() {
+        use arbiter_crypto::hashing::Hashable;
+        use sha2::Digest;
+
+        let active = shared_settings();
+        let revoked = SharedGrantSettings {
+            revoked_at: Some(Utc::now()),
+            ..shared_settings()
+        };
+
+        let mut active_hash = sha2::Sha256::new();
+        active.hash(&mut active_hash);
+
+        let mut revoked_hash = sha2::Sha256::new();
+        revoked.hash(&mut revoked_hash);
+
+        assert_ne!(active_hash.finalize(), revoked_hash.finalize());
+    }
 }

server/crates/arbiter-server/src/evm/policies.rs

@@ -1,8 +1,4 @@
-use crate::{
+use std::fmt::Display;
-    crypto::integrity::v1::Integrable,
-    db::models::{EvmBasicGrant, EvmWalletAccess},
-    evm::utils,
-};
 
 use alloy::primitives::{Address, Bytes, ChainId, U256};
 use chrono::{DateTime, Duration, Utc};
@@ -10,9 +6,15 @@ use diesel::{
     ExpressionMethods as _, QueryDsl, SelectableHelper, result::QueryResult, sqlite::Sqlite,
 };
 use diesel_async::{AsyncConnection, RunQueryDsl};
-use std::fmt::Display;
+
 use thiserror::Error;
 
+use crate::{
+    crypto::integrity::v1::Integrable,
+    db::models::{self, EvmBasicGrant, EvmWalletAccess},
+    evm::utils,
+};
+
 pub mod ether_transfer;
 pub mod token_transfers;
 
@@ -85,10 +87,10 @@ pub trait Policy: Sized {
 
     // Create a new grant in the database based on the provided grant details, and return its ID
     fn create_grant(
-        basic: &EvmBasicGrant,
+        basic: &models::EvmBasicGrant,
         grant: &Self::Settings,
         conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    ) -> impl Future<Output = QueryResult<DatabaseID>> + Send;
+    ) -> impl std::future::Future<Output = QueryResult<DatabaseID>> + Send;
 
     // Try to find an existing grant that matches the transaction context, and return its details if found
     // Additionally, return ID of basic grant for shared-logic checks like rate limits and validity periods
@@ -144,6 +146,7 @@ pub struct SharedGrantSettings {
 
     pub valid_from: Option<DateTime<Utc>>,
     pub valid_until: Option<DateTime<Utc>>,
+    pub revoked_at: Option<DateTime<Utc>>,
 
     pub max_gas_fee_per_gas: Option<U256>,
     pub max_priority_fee_per_gas: Option<U256>,
@@ -155,9 +158,10 @@ impl SharedGrantSettings {
     pub(crate) fn try_from_model(model: EvmBasicGrant) -> QueryResult<Self> {
         Ok(Self {
             wallet_access_id: model.wallet_access_id,
-            chain: model.chain_id.into(),
+            chain: model.chain_id as u64, // safe because chain_id is stored as i32 but is guaranteed to be a valid ChainId by the API when creating grants
             valid_from: model.valid_from.map(Into::into),
             valid_until: model.valid_until.map(Into::into),
+            revoked_at: model.revoked_at.map(Into::into),
             max_gas_fee_per_gas: model
                 .max_gas_fee_per_gas
                 .map(|b| utils::try_bytes_to_u256(&b))
@@ -166,11 +170,10 @@ impl SharedGrantSettings {
                 .max_priority_fee_per_gas
                 .map(|b| utils::try_bytes_to_u256(&b))
                 .transpose()?,
-            #[expect(clippy::cast_sign_loss, clippy::as_conversions, reason = "fixme! #86")]
             rate_limit: match (model.rate_limit_count, model.rate_limit_window_secs) {
                 (Some(count), Some(window_secs)) => Some(TransactionRateLimit {
                     count: count as u32,
-                    window: Duration::seconds(window_secs.into()),
+                    window: Duration::seconds(window_secs as i64),
                 }),
                 _ => None,
             },
@@ -180,7 +183,7 @@ impl SharedGrantSettings {
     pub async fn query_by_id(
         conn: &mut impl AsyncConnection<Backend = Sqlite>,
         id: i32,
-    ) -> QueryResult<Self> {
+    ) -> diesel::result::QueryResult<Self> {
         use crate::db::schema::evm_basic_grant;
 
         let basic_grant: EvmBasicGrant = evm_basic_grant::table

server/crates/arbiter-server/src/evm/policies/ether_transfer/mod.rs

@@ -1,31 +1,29 @@
-use super::{DatabaseID, EvalContext, EvalViolation};
+use std::collections::HashMap;
-use crate::{
+use std::fmt::Display;
-    crypto::integrity::v1::Integrable,
-    db::models::{
-        EvmBasicGrant, EvmEtherTransferGrant, EvmEtherTransferGrantTarget, EvmEtherTransferLimit,
-        NewEvmEtherTransferLimit, SqliteTimestamp,
-    },
-    db::schema::{evm_basic_grant, evm_ether_transfer_limit, evm_transaction_log},
-    db::{
-        models::{NewEvmEtherTransferGrant, NewEvmEtherTransferGrantTarget},
-        schema::{evm_ether_transfer_grant, evm_ether_transfer_grant_target},
-    },
-    evm::policies::{
-        CombinedSettings, Grant, SharedGrantSettings, SpecificGrant, SpecificMeaning,
-        VolumeRateLimit,
-    },
-    evm::{policies::Policy, utils},
-};
 
 use alloy::primitives::{Address, U256};
 use chrono::{DateTime, Duration, Utc};
-use diesel::{
+use diesel::dsl::{auto_type, insert_into};
-    dsl::{auto_type, insert_into},
+use diesel::sqlite::Sqlite;
-    prelude::*,
+use diesel::{ExpressionMethods, JoinOnDsl, prelude::*};
-    sqlite::Sqlite,
-};
 use diesel_async::{AsyncConnection, RunQueryDsl};
-use std::{collections::HashMap, fmt::Display};
+
+use crate::crypto::integrity::v1::Integrable;
+use crate::db::models::{
+    EvmBasicGrant, EvmEtherTransferGrant, EvmEtherTransferGrantTarget, EvmEtherTransferLimit,
+    NewEvmEtherTransferLimit, SqliteTimestamp,
+};
+use crate::db::schema::{evm_basic_grant, evm_ether_transfer_limit, evm_transaction_log};
+use crate::evm::policies::{
+    CombinedSettings, Grant, SharedGrantSettings, SpecificGrant, SpecificMeaning, VolumeRateLimit,
+};
+use crate::{
+    db::{
+        models::{self, NewEvmEtherTransferGrant, NewEvmEtherTransferGrantTarget},
+        schema::{evm_ether_transfer_grant, evm_ether_transfer_grant_target},
+    },
+    evm::{policies::Policy, utils},
+};
 
 #[auto_type]
 fn grant_join() -> _ {
@@ -34,6 +32,8 @@ fn grant_join() -> _ {
     )
 }
 
+use super::{DatabaseID, EvalContext, EvalViolation};
+
 // Plain ether transfer
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]
 pub struct Meaning {
@@ -46,8 +46,8 @@ impl Display for Meaning {
     }
 }
 impl From<Meaning> for SpecificMeaning {
-    fn from(val: Meaning) -> Self {
+    fn from(val: Meaning) -> SpecificMeaning {
-        Self::EtherTransfer(val)
+        SpecificMeaning::EtherTransfer(val)
     }
 }
 
@@ -62,8 +62,8 @@ impl Integrable for Settings {
 }
 
 impl From<Settings> for SpecificGrant {
-    fn from(val: Settings) -> Self {
+    fn from(val: Settings) -> SpecificGrant {
-        Self::EtherTransfer(val)
+        SpecificGrant::EtherTransfer(val)
     }
 }
 
@@ -74,7 +74,9 @@ async fn query_relevant_past_transaction(
 ) -> QueryResult<Vec<(U256, DateTime<Utc>)>> {
     let past_transactions: Vec<(Vec<u8>, SqliteTimestamp)> = evm_transaction_log::table
         .filter(evm_transaction_log::grant_id.eq(grant_id))
-        .filter(evm_transaction_log::signed_at.ge(SqliteTimestamp(Utc::now() - longest_window)))
+        .filter(
+            evm_transaction_log::signed_at.ge(SqliteTimestamp(chrono::Utc::now() - longest_window)),
+        )
         .select((
             evm_transaction_log::eth_value,
             evm_transaction_log::signed_at,
@@ -101,7 +103,7 @@ async fn check_rate_limits(
 
     let past_transaction = query_relevant_past_transaction(grant.id, window, db).await?;
 
-    let window_start = Utc::now() - grant.settings.specific.limit.window;
+    let window_start = chrono::Utc::now() - grant.settings.specific.limit.window;
     let prospective_cumulative_volume: U256 = past_transaction
         .iter()
         .filter(|(_, timestamp)| timestamp >= &window_start)
@@ -151,15 +153,10 @@ impl Policy for EtherTransfer {
     }
 
     async fn create_grant(
-        basic: &EvmBasicGrant,
+        basic: &models::EvmBasicGrant,
         grant: &Self::Settings,
         conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    ) -> QueryResult<DatabaseID> {
+    ) -> diesel::result::QueryResult<DatabaseID> {
-        #[expect(
-            clippy::cast_possible_truncation,
-            clippy::as_conversions,
-            reason = "fixme! #86"
-        )]
         let limit_id: i32 = insert_into(evm_ether_transfer_limit::table)
             .values(NewEvmEtherTransferLimit {
                 window_secs: grant.limit.window.num_seconds() as i32,
@@ -194,7 +191,7 @@ impl Policy for EtherTransfer {
     async fn try_find_grant(
         context: &EvalContext,
         conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    ) -> QueryResult<Option<Grant<Self::Settings>>> {
+    ) -> diesel::result::QueryResult<Option<Grant<Self::Settings>>> {
         let target_bytes = context.to.to_vec();
 
         // Find a grant where:
@@ -248,7 +245,7 @@ impl Policy for EtherTransfer {
             limit: VolumeRateLimit {
                 max_volume: utils::try_bytes_to_u256(&limit.max_volume)
                     .map_err(|err| diesel::result::Error::DeserializationError(Box::new(err)))?,
-                window: Duration::seconds(limit.window_secs.into()),
+                window: chrono::Duration::seconds(limit.window_secs as i64),
             },
         };
 
@@ -268,7 +265,7 @@ impl Policy for EtherTransfer {
         _log_id: i32,
         _grant: &Grant<Self::Settings>,
         _conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    ) -> QueryResult<()> {
+    ) -> diesel::result::QueryResult<()> {
         // Basic log is sufficient
 
         Ok(())
@@ -321,7 +318,7 @@ impl Policy for EtherTransfer {
             .map(|(basic, specific)| {
                 let targets: Vec<Address> = targets_by_grant
                     .get(&specific.id)
-                    .map(Vec::as_slice)
+                    .map(|v| v.as_slice())
                     .unwrap_or_default()
                     .iter()
                     .filter_map(|t| {
@@ -345,7 +342,7 @@ impl Policy for EtherTransfer {
                                 max_volume: utils::try_bytes_to_u256(&limit.max_volume).map_err(
                                     |e| diesel::result::Error::DeserializationError(Box::new(e)),
                                 )?,
-                                window: Duration::seconds(limit.window_secs.into()),
+                                window: Duration::seconds(limit.window_secs as i64),
                             },
                         },
                     },

server/crates/arbiter-server/src/evm/policies/ether_transfer/tests.rs

@@ -1,29 +1,27 @@
-use super::{EtherTransfer, Settings};
-use crate::{
-    db::{
-        self, DatabaseConnection,
-        models::{
-            EvmBasicGrant, EvmWalletAccess, EvmWalletId, NewEvmBasicGrant, NewEvmTransactionLog,
-            SqliteTimestamp,
-        },
-        schema::{evm_basic_grant, evm_transaction_log},
-    },
-    evm::{
-        policies::{
-            CombinedSettings, EvalContext, EvalViolation, Grant, Policy, SharedGrantSettings,
-            VolumeRateLimit,
-        },
-        utils,
-    },
-};
-
 use alloy::primitives::{Address, Bytes, U256, address};
 use chrono::{Duration, Utc};
 use diesel::{SelectableHelper, insert_into};
 use diesel_async::RunQueryDsl;
 
+use crate::db::{
+    self, DatabaseConnection,
+    models::{
+        EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, NewEvmTransactionLog, SqliteTimestamp,
+    },
+    schema::{evm_basic_grant, evm_transaction_log},
+};
+use crate::evm::{
+    policies::{
+        CombinedSettings, EvalContext, EvalViolation, Grant, Policy, SharedGrantSettings,
+        VolumeRateLimit,
+    },
+    utils,
+};
+
+use super::{EtherTransfer, Settings};
+
 const WALLET_ACCESS_ID: i32 = 1;
-const CHAIN_ID: alloy::primitives::ChainId = 1;
+const CHAIN_ID: u64 = 1;
 
 const ALLOWED: Address = address!("1111111111111111111111111111111111111111");
 const OTHER: Address = address!("2222222222222222222222222222222222222222");
@@ -32,7 +30,7 @@ fn ctx(to: Address, value: U256) -> EvalContext {
     EvalContext {
         target: EvmWalletAccess {
             id: WALLET_ACCESS_ID,
-            wallet_id: EvmWalletId::from_raw(10),
+            wallet_id: 10,
             client_id: 20,
             created_at: SqliteTimestamp(Utc::now()),
         },
@@ -49,7 +47,7 @@ async fn insert_basic(conn: &mut DatabaseConnection, revoked: bool) -> EvmBasicG
     insert_into(evm_basic_grant::table)
         .values(NewEvmBasicGrant {
             wallet_access_id: WALLET_ACCESS_ID,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             valid_from: None,
             valid_until: None,
             max_gas_fee_per_gas: None,
@@ -80,6 +78,7 @@ fn shared() -> SharedGrantSettings {
         chain: CHAIN_ID,
         valid_from: None,
         valid_until: None,
+        revoked_at: None,
         max_gas_fee_per_gas: None,
         max_priority_fee_per_gas: None,
         rate_limit: None,
@@ -162,7 +161,7 @@ async fn evaluate_passes_when_volume_within_limit() {
         .values(NewEvmTransactionLog {
             grant_id,
             wallet_access_id: WALLET_ACCESS_ID,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             eth_value: utils::u256_to_bytes(U256::from(500u64)).to_vec(),
             signed_at: SqliteTimestamp(Utc::now()),
         })
@@ -204,7 +203,7 @@ async fn evaluate_rejects_volume_over_limit() {
         .values(NewEvmTransactionLog {
             grant_id,
             wallet_access_id: WALLET_ACCESS_ID,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             eth_value: utils::u256_to_bytes(U256::from(1_000u64)).to_vec(),
             signed_at: SqliteTimestamp(Utc::now()),
         })
@@ -247,7 +246,7 @@ async fn evaluate_passes_at_exactly_volume_limit() {
         .values(NewEvmTransactionLog {
             grant_id,
             wallet_access_id: WALLET_ACCESS_ID,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             eth_value: utils::u256_to_bytes(U256::from(900u64)).to_vec(),
             signed_at: SqliteTimestamp(Utc::now()),
         })

server/crates/arbiter-server/src/evm/policies/token_transfers/mod.rs

@@ -1,4 +1,16 @@
-use super::{DatabaseID, EvalContext, EvalViolation};
+use std::collections::HashMap;
+
+use crate::db::schema::{
+    evm_basic_grant, evm_token_transfer_grant, evm_token_transfer_log,
+    evm_token_transfer_volume_limit,
+};
+use crate::evm::{
+    abi::IERC20::transferCall,
+    policies::{
+        Grant, Policy, SharedGrantSettings, SpecificGrant, SpecificMeaning, VolumeRateLimit,
+    },
+    utils,
+};
 use crate::{
     crypto::integrity::Integrable,
     db::models::{
@@ -6,33 +18,20 @@ use crate::{
         NewEvmTokenTransferGrant, NewEvmTokenTransferLog, NewEvmTokenTransferVolumeLimit,
         SqliteTimestamp,
     },
-    db::schema::{
-        evm_basic_grant, evm_token_transfer_grant, evm_token_transfer_log,
-        evm_token_transfer_volume_limit,
-    },
     evm::policies::CombinedSettings,
-    evm::{
-        abi::IERC20::transferCall,
-        policies::{
-            Grant, Policy, SharedGrantSettings, SpecificGrant, SpecificMeaning, VolumeRateLimit,
-        },
-        utils,
-    },
 };
-use arbiter_tokens_registry::evm::nonfungible::{self, TokenInfo};
-
 use alloy::{
     primitives::{Address, U256},
     sol_types::SolCall,
 };
+use arbiter_tokens_registry::evm::nonfungible::{self, TokenInfo};
 use chrono::{DateTime, Duration, Utc};
-use diesel::{
+use diesel::dsl::{auto_type, insert_into};
-    dsl::{auto_type, insert_into},
+use diesel::sqlite::Sqlite;
-    prelude::*,
+use diesel::{ExpressionMethods, prelude::*};
-    sqlite::Sqlite,
-};
 use diesel_async::{AsyncConnection, RunQueryDsl};
-use std::collections::HashMap;
+
+use super::{DatabaseID, EvalContext, EvalViolation};
 
 #[auto_type]
 fn grant_join() -> _ {
@@ -57,8 +56,8 @@ impl std::fmt::Display for Meaning {
     }
 }
 impl From<Meaning> for SpecificMeaning {
-    fn from(val: Meaning) -> Self {
+    fn from(val: Meaning) -> SpecificMeaning {
-        Self::TokenTransfer(val)
+        SpecificMeaning::TokenTransfer(val)
     }
 }
 
@@ -74,8 +73,8 @@ impl Integrable for Settings {
 }
 
 impl From<Settings> for SpecificGrant {
-    fn from(val: Settings) -> Self {
+    fn from(val: Settings) -> SpecificGrant {
-        Self::TokenTransfer(val)
+        SpecificGrant::TokenTransfer(val)
     }
 }
 
@@ -86,7 +85,10 @@ async fn query_relevant_past_transfers(
 ) -> QueryResult<Vec<(U256, DateTime<Utc>)>> {
     let past_logs: Vec<(Vec<u8>, SqliteTimestamp)> = evm_token_transfer_log::table
         .filter(evm_token_transfer_log::grant_id.eq(grant_id))
-        .filter(evm_token_transfer_log::created_at.ge(SqliteTimestamp(Utc::now() - longest_window)))
+        .filter(
+            evm_token_transfer_log::created_at
+                .ge(SqliteTimestamp(chrono::Utc::now() - longest_window)),
+        )
         .select((
             evm_token_transfer_log::value,
             evm_token_transfer_log::created_at,
@@ -126,7 +128,7 @@ async fn check_volume_rate_limits(
     let past_transfers = query_relevant_past_transfers(grant.id, longest_window, db).await?;
 
     for limit in &grant.settings.specific.volume_limits {
-        let window_start = Utc::now() - limit.window;
+        let window_start = chrono::Utc::now() - limit.window;
         let prospective_cumulative_volume: U256 = past_transfers
             .iter()
             .filter(|(_, timestamp)| timestamp >= &window_start)
@@ -202,11 +204,6 @@ impl Policy for TokenTransfer {
             .await?;
 
         for limit in &grant.volume_limits {
-            #[expect(
-                clippy::cast_possible_truncation,
-                clippy::as_conversions,
-                reason = "fixme! #86"
-            )]
             insert_into(evm_token_transfer_volume_limit::table)
                 .values(NewEvmTokenTransferVolumeLimit {
                     grant_id,
@@ -256,7 +253,7 @@ impl Policy for TokenTransfer {
                     max_volume: utils::try_bytes_to_u256(&row.max_volume).map_err(|err| {
                         diesel::result::Error::DeserializationError(Box::new(err))
                     })?,
-                    window: Duration::seconds(row.window_secs.into()),
+                    window: Duration::seconds(row.window_secs as i64),
                 })
             })
             .collect::<QueryResult<Vec<_>>>()?;
@@ -306,7 +303,7 @@ impl Policy for TokenTransfer {
             .values(NewEvmTokenTransferLog {
                 grant_id: grant.id,
                 log_id,
-                chain_id: context.chain.into(),
+                chain_id: context.chain as i32,
                 token_contract: context.to.to_vec(),
                 recipient_address: meaning.to.to_vec(),
                 value: utils::u256_to_bytes(meaning.value).to_vec(),
@@ -355,7 +352,7 @@ impl Policy for TokenTransfer {
             .map(|(basic, specific)| {
                 let volume_limits: Vec<VolumeRateLimit> = limits_by_grant
                     .get(&specific.id)
-                    .map(Vec::as_slice)
+                    .map(|v| v.as_slice())
                     .unwrap_or_default()
                     .iter()
                     .map(|row| {
@@ -363,7 +360,7 @@ impl Policy for TokenTransfer {
                             max_volume: utils::try_bytes_to_u256(&row.max_volume).map_err(|e| {
                                 diesel::result::Error::DeserializationError(Box::new(e))
                             })?,
-                            window: Duration::seconds(row.window_secs.into()),
+                            window: Duration::seconds(row.window_secs as i64),
                         })
                     })
                     .collect::<QueryResult<Vec<_>>>()?;

server/crates/arbiter-server/src/evm/policies/token_transfers/tests.rs

@@ -1,27 +1,24 @@
-use super::{Settings, TokenTransfer};
+use alloy::primitives::{Address, Bytes, U256, address};
-use crate::{
+use alloy::sol_types::SolCall;
-    db::{
+use chrono::{Duration, Utc};
+use diesel::{SelectableHelper, insert_into};
+use diesel_async::RunQueryDsl;
+
+use crate::db::{
     self, DatabaseConnection,
-        models::{EvmBasicGrant, EvmWalletAccess, EvmWalletId, NewEvmBasicGrant, SqliteTimestamp},
+    models::{EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, SqliteTimestamp},
     schema::evm_basic_grant,
-    },
+};
-    evm::{
+use crate::evm::{
     abi::IERC20::transferCall,
     policies::{
         CombinedSettings, EvalContext, EvalViolation, Grant, Policy, SharedGrantSettings,
         VolumeRateLimit,
     },
     utils,
-    },
 };
 
-use alloy::{
+use super::{Settings, TokenTransfer};
-    primitives::{Address, Bytes, U256, address},
-    sol_types::SolCall,
-};
-use chrono::{Duration, Utc};
-use diesel::{SelectableHelper, insert_into};
-use diesel_async::RunQueryDsl;
 
 // DAI on Ethereum mainnet — present in the static token registry
 const CHAIN_ID: u64 = 1;
@@ -45,7 +42,7 @@ fn ctx(to: Address, calldata: Bytes) -> EvalContext {
     EvalContext {
         target: EvmWalletAccess {
             id: WALLET_ACCESS_ID,
-            wallet_id: EvmWalletId::from_raw(10),
+            wallet_id: 10,
             client_id: 20,
             created_at: SqliteTimestamp(Utc::now()),
         },
@@ -62,7 +59,7 @@ async fn insert_basic(conn: &mut DatabaseConnection, revoked: bool) -> EvmBasicG
     insert_into(evm_basic_grant::table)
         .values(NewEvmBasicGrant {
             wallet_access_id: WALLET_ACCESS_ID,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             valid_from: None,
             valid_until: None,
             max_gas_fee_per_gas: None,
@@ -98,6 +95,7 @@ fn shared() -> SharedGrantSettings {
         chain: CHAIN_ID,
         valid_from: None,
         valid_until: None,
+        revoked_at: None,
         max_gas_fee_per_gas: None,
         max_priority_fee_per_gas: None,
         rate_limit: None,
@@ -241,11 +239,12 @@ async fn evaluate_passes_volume_at_exact_limit() {
         .unwrap();
 
     // Record a past transfer of 900, with current transfer 100 => exactly 1000 limit
-    insert_into(db::schema::evm_token_transfer_log::table)
+    use crate::db::{models::NewEvmTokenTransferLog, schema::evm_token_transfer_log};
-        .values(db::models::NewEvmTokenTransferLog {
+    insert_into(evm_token_transfer_log::table)
+        .values(NewEvmTokenTransferLog {
             grant_id,
             log_id: 0,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             token_contract: DAI.to_vec(),
             recipient_address: RECIPIENT.to_vec(),
             value: utils::u256_to_bytes(U256::from(900u64)).to_vec(),
@@ -285,11 +284,12 @@ async fn evaluate_rejects_volume_over_limit() {
         .await
         .unwrap();
 
-    insert_into(db::schema::evm_token_transfer_log::table)
+    use crate::db::{models::NewEvmTokenTransferLog, schema::evm_token_transfer_log};
-        .values(db::models::NewEvmTokenTransferLog {
+    insert_into(evm_token_transfer_log::table)
+        .values(NewEvmTokenTransferLog {
             grant_id,
             log_id: 0,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             token_contract: DAI.to_vec(),
             recipient_address: RECIPIENT.to_vec(),
             value: utils::u256_to_bytes(U256::from(1_000u64)).to_vec(),

server/crates/arbiter-server/src/evm/safe_signer.rs

@@ -1,4 +1,4 @@
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
+use std::sync::Mutex;
 
 use alloy::{
     consensus::SignableTransaction,
@@ -6,9 +6,9 @@ use alloy::{
     primitives::{Address, B256, ChainId, Signature},
     signers::{Error, Result, Signer, SignerSync, utils::secret_key_to_address},
 };
+use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
 use async_trait::async_trait;
 use k256::ecdsa::{self, RecoveryId, SigningKey, signature::hazmat::PrehashSigner};
-use std::sync::Mutex;
 
 /// An Ethereum signer that stores its secp256k1 secret key inside a
 /// hardware-protected [`MemSafe`] cell.
@@ -44,7 +44,7 @@ impl std::fmt::Debug for SafeSigner {
 /// Returns the protected key bytes and the derived Ethereum address.
 pub fn generate(rng: &mut impl rand::Rng) -> (SafeCell<[u8; 32]>, Address) {
     loop {
-        let mut cell = SafeCell::new_inline_default(|w: &mut [u8; 32]| {
+        let mut cell = SafeCell::new_inline(|w: &mut [u8; 32]| {
             rng.fill_bytes(w);
         });
 
@@ -82,8 +82,8 @@ impl SafeSigner {
         })
     }
 
-    #[expect(clippy::significant_drop_tightening, reason = "false positive")]
     fn sign_hash_inner(&self, hash: &B256) -> Result<Signature> {
+        #[allow(clippy::expect_used)]
         let mut cell = self.key.lock().expect("SafeSigner mutex poisoned");
         let reader = cell.read();
         let sig: (ecdsa::Signature, RecoveryId) = reader.sign_prehash(hash.as_ref())?;
@@ -96,6 +96,7 @@ impl SafeSigner {
         {
             return Err(Error::TransactionChainIdMismatch {
                 signer: chain_id,
+                #[allow(clippy::expect_used)]
                 tx: tx.chain_id().expect("Chain ID is guaranteed to be set"),
             });
         }

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

@@ -2,20 +2,20 @@ use alloy::primitives::U256;
 
 #[derive(thiserror::Error, Debug)]
 #[error("Expected {expected} bytes but got {actual} bytes")]
-pub(super) struct LengthError {
+pub struct LengthError {
-    pub(super) expected: usize,
+    pub expected: usize,
-    pub(super) actual: usize,
+    pub actual: usize,
 }
 
-pub const fn u256_to_bytes(value: U256) -> [u8; 32] {
+pub fn u256_to_bytes(value: U256) -> [u8; 32] {
     value.to_le_bytes()
 }
-pub(super) fn bytes_to_u256(bytes: &[u8]) -> Option<U256> {
+pub fn bytes_to_u256(bytes: &[u8]) -> Option<U256> {
     let bytes: [u8; 32] = bytes.try_into().ok()?;
     Some(U256::from_le_bytes(bytes))
 }
 
-pub(super) fn try_bytes_to_u256(bytes: &[u8]) -> diesel::result::QueryResult<U256> {
+pub fn try_bytes_to_u256(bytes: &[u8]) -> diesel::result::QueryResult<U256> {
     let bytes: [u8; 32] = bytes.try_into().map_err(|_| {
         diesel::result::Error::DeserializationError(Box::new(LengthError {
             expected: 32,

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

@@ -1,7 +1,3 @@
-use crate::{
-    grpc::request_tracker::RequestTracker,
-    peers::client::{ClientConnection, session::ClientSession},
-};
 use arbiter_proto::{
     proto::client::{
         ClientRequest, ClientResponse, client_request::Payload as ClientRequestPayload,
@@ -9,11 +5,15 @@ use arbiter_proto::{
     },
     transport::{Receiver, Sender, grpc::GrpcBi},
 };
-
 use kameo::actor::{ActorRef, Spawn as _};
 use tonic::Status;
 use tracing::{info, warn};
 
+use crate::{
+    actors::client::{ClientConnection, session::ClientSession},
+    grpc::request_tracker::RequestTracker,
+};
+
 mod auth;
 mod evm;
 mod inbound;
@@ -98,7 +98,8 @@ pub async fn start(mut conn: ClientConnection, mut bi: GrpcBi<ClientRequest, Cli
         Err(err) => {
             let _ = bi
                 .send(Err(Status::unauthenticated(format!(
-                    "Authentication failed: {err}",
+                    "Authentication failed: {}",
+                    err
                 ))))
                 .await;
             warn!(error = ?err, "Client authentication failed");

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

@@ -1,7 +1,3 @@
-use crate::{
-    grpc::{Convert, request_tracker::RequestTracker},
-    peers::client::{ClientConnection, auth},
-};
 use arbiter_crypto::authn;
 use arbiter_proto::{
     ClientMetadata,
@@ -21,18 +17,22 @@ use arbiter_proto::{
     },
     transport::{Bi, Error as TransportError, Receiver, Sender, grpc::GrpcBi},
 };
-
 use async_trait::async_trait;
 use tonic::Status;
 use tracing::warn;
 
-pub(super) struct AuthTransportAdapter<'a> {
+use crate::{
+    actors::client::{self, ClientConnection, auth},
+    grpc::request_tracker::RequestTracker,
+};
+
+pub struct AuthTransportAdapter<'a> {
     bi: &'a mut GrpcBi<ClientRequest, ClientResponse>,
     request_tracker: &'a mut RequestTracker,
 }
 
 impl<'a> AuthTransportAdapter<'a> {
-    pub(super) const fn new(
+    pub fn new(
         bi: &'a mut GrpcBi<ClientRequest, ClientResponse>,
         request_tracker: &'a mut RequestTracker,
     ) -> Self {
@@ -42,6 +42,40 @@ impl<'a> AuthTransportAdapter<'a> {
         }
     }
 
+    fn response_to_proto(response: auth::Outbound) -> AuthResponsePayload {
+        match response {
+            auth::Outbound::AuthChallenge { pubkey, nonce } => {
+                AuthResponsePayload::Challenge(ProtoAuthChallenge {
+                    pubkey: pubkey.to_bytes(),
+                    nonce,
+                })
+            }
+            auth::Outbound::AuthSuccess => {
+                AuthResponsePayload::Result(ProtoAuthResult::Success.into())
+            }
+        }
+    }
+
+    fn error_to_proto(error: auth::Error) -> AuthResponsePayload {
+        AuthResponsePayload::Result(
+            match error {
+                auth::Error::InvalidChallengeSolution => ProtoAuthResult::InvalidSignature,
+                auth::Error::ApproveError(auth::ApproveError::Denied) => {
+                    ProtoAuthResult::ApprovalDenied
+                }
+                auth::Error::ApproveError(auth::ApproveError::Upstream(
+                    crate::actors::flow_coordinator::ApprovalError::NoUserAgentsConnected,
+                )) => ProtoAuthResult::NoUserAgentsOnline,
+                auth::Error::ApproveError(auth::ApproveError::Internal)
+                | auth::Error::DatabasePoolUnavailable
+                | auth::Error::DatabaseOperationFailed
+                | auth::Error::IntegrityCheckFailed
+                | auth::Error::Transport => ProtoAuthResult::Internal,
+            }
+            .into(),
+        )
+    }
+
     async fn send_client_response(
         &mut self,
         payload: AuthResponsePayload,
@@ -69,8 +103,8 @@ impl Sender<Result<auth::Outbound, auth::Error>> for AuthTransportAdapter<'_> {
         item: Result<auth::Outbound, auth::Error>,
     ) -> Result<(), TransportError> {
         let payload = match item {
-            Ok(message) => message.convert(),
+            Ok(message) => AuthTransportAdapter::response_to_proto(message),
-            Err(err) => err.convert(),
+            Err(err) => AuthTransportAdapter::error_to_proto(err),
         };
 
         self.send_client_response(payload).await
@@ -133,7 +167,7 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
                 };
                 Some(auth::Inbound::AuthChallengeRequest {
                     pubkey,
-                    metadata: client_info.convert(),
+                    metadata: client_metadata_from_proto(client_info),
                 })
             }
             AuthRequestPayload::ChallengeSolution(ProtoAuthChallengeSolution { signature }) => {
@@ -151,69 +185,19 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
 
 impl Bi<auth::Inbound, Result<auth::Outbound, auth::Error>> for AuthTransportAdapter<'_> {}
 
-impl Convert for ProtoClientInfo {
+fn client_metadata_from_proto(metadata: ProtoClientInfo) -> ClientMetadata {
-    type Output = ClientMetadata;
-
-    fn convert(self) -> Self::Output {
     ClientMetadata {
-            name: self.name,
+        name: metadata.name,
-            description: self.description,
+        description: metadata.description,
-            version: self.version,
+        version: metadata.version,
-        }
-    }
-}
-
-impl Convert for auth::Error {
-    type Output = AuthResponsePayload;
-
-    fn convert(self) -> Self::Output {
-        use auth::Error::{
-            ApproveError, DatabaseOperationFailed, DatabasePoolUnavailable, IntegrityCheckFailed,
-            InvalidChallengeSolution, Transport,
-        };
-        AuthResponsePayload::Result(
-            match self {
-                InvalidChallengeSolution => ProtoAuthResult::InvalidSignature,
-                ApproveError(auth::ApproveError::Denied) => ProtoAuthResult::ApprovalDenied,
-                ApproveError(auth::ApproveError::Upstream(
-                    crate::actors::flow_coordinator::ApprovalError::NoOperatorsConnected,
-                )) => ProtoAuthResult::NoOperatorsOnline,
-                ApproveError(auth::ApproveError::Internal)
-                | DatabasePoolUnavailable
-                | DatabaseOperationFailed
-                | IntegrityCheckFailed
-                | Transport => ProtoAuthResult::Internal,
-            }
-            .into(),
-        )
     }
 }
 
-impl Convert for auth::Outbound {
+pub async fn start(
-    type Output = AuthResponsePayload;
-
-    fn convert(self) -> Self::Output {
-        match self {
-            Self::AuthChallenge { challenge } => {
-                AuthResponsePayload::Challenge(ProtoAuthChallenge {
-                    timestamp_nanos: challenge
-                        .timestamp
-                        .timestamp_nanos_opt()
-                        .expect("timestamp within range")
-                        as u64,
-                    random: challenge.nonce.to_vec(),
-                })
-            }
-            Self::AuthSuccess => AuthResponsePayload::Result(ProtoAuthResult::Success.into()),
-        }
-    }
-}
-
-pub(super) async fn start(
     conn: &mut ClientConnection,
     bi: &mut GrpcBi<ClientRequest, ClientResponse>,
     request_tracker: &mut RequestTracker,
 ) -> Result<i32, auth::Error> {
     let mut transport = AuthTransportAdapter::new(bi, request_tracker);
-    auth::authenticate(conn, &mut transport).await
+    client::auth::authenticate(conn, &mut transport).await
 }

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

@@ -1,10 +1,3 @@
-use crate::{
-    grpc::{
-        Convert, TryConvert,
-        common::inbound::{RawEvmAddress, RawEvmTransaction},
-    },
-    peers::client::session::{ClientSession, HandleSignTransaction, SignTransactionRpcError},
-};
 use arbiter_proto::proto::{
     client::{
         client_response::Payload as ClientResponsePayload,
@@ -18,12 +11,19 @@ use arbiter_proto::proto::{
         evm_sign_transaction_response::Result as EvmSignTransactionResult,
     },
 };
-
 use kameo::actor::ActorRef;
 use tonic::Status;
 use tracing::warn;
 
-const fn wrap_response(payload: EvmResponsePayload) -> ClientResponsePayload {
+use crate::{
+    actors::client::session::{ClientSession, HandleSignTransaction, SignTransactionRpcError},
+    grpc::{
+        Convert, TryConvert,
+        common::inbound::{RawEvmAddress, RawEvmTransaction},
+    },
+};
+
+fn wrap_response(payload: EvmResponsePayload) -> ClientResponsePayload {
     ClientResponsePayload::Evm(proto_evm::Response {
         payload: Some(payload),
     })

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

@@ -1,7 +1,3 @@
-use crate::{
-    actors::vault::VaultState,
-    peers::client::session::{ClientSession, Error, HandleQueryVaultState},
-};
 use arbiter_proto::proto::{
     client::{
         client_response::Payload as ClientResponsePayload,
@@ -12,11 +8,15 @@ use arbiter_proto::proto::{
     },
     shared::VaultState as ProtoVaultState,
 };
-
 use kameo::{actor::ActorRef, error::SendError};
 use tonic::Status;
 use tracing::warn;
 
+use crate::actors::{
+    client::session::{ClientSession, Error, HandleQueryVaultState},
+    keyholder::KeyHolderState,
+};
+
 pub(super) async fn dispatch(
     actor: &ActorRef<ClientSession>,
     req: proto_vault::Request,
@@ -28,12 +28,11 @@ pub(super) async fn dispatch(
     };
 
     match payload {
-        VaultRequestPayload::QueryState(()) => {
+        VaultRequestPayload::QueryState(_) => {
             let state = match actor.ask(HandleQueryVaultState {}).await {
-                Ok(VaultState::Unbootstrapped) => ProtoVaultState::Unbootstrapped,
+                Ok(KeyHolderState::Unbootstrapped) => ProtoVaultState::Unbootstrapped,
-                Ok(VaultState::Bootstrapping) => ProtoVaultState::Boostrapping,
+                Ok(KeyHolderState::Sealed) => ProtoVaultState::Sealed,
-                Ok(VaultState::Sealed) => ProtoVaultState::Sealed,
+                Ok(KeyHolderState::Unsealed) => ProtoVaultState::Unsealed,
-                Ok(VaultState::Unsealed) => ProtoVaultState::Unsealed,
                 Err(SendError::HandlerError(Error::Internal)) => ProtoVaultState::Error,
                 Err(err) => {
                     warn!(error = ?err, "Failed to query vault state");

server/crates/arbiter-server/src/grpc/common.rs

@@ -1,2 +1,2 @@
-pub(super) mod inbound;
+pub mod inbound;
-pub(super) mod outbound;
+pub mod outbound;

server/crates/arbiter-server/src/grpc/common/inbound.rs

@@ -1,8 +1,8 @@
-use crate::grpc::TryConvert;
-
 use alloy::{consensus::TxEip1559, primitives::Address, rlp::Decodable as _};
 
-pub(in crate::grpc) struct RawEvmAddress(pub(in crate::grpc) Vec<u8>);
+use crate::grpc::TryConvert;
+
+pub struct RawEvmAddress(pub Vec<u8>);
 impl TryConvert for RawEvmAddress {
     type Output = Address;
 
@@ -21,7 +21,7 @@ impl TryConvert for RawEvmAddress {
     }
 }
 
-pub(in crate::grpc) struct RawEvmTransaction(pub(in crate::grpc) Vec<u8>);
+pub struct RawEvmTransaction(pub Vec<u8>);
 impl TryConvert for RawEvmTransaction {
     type Output = TxEip1559;
 

server/crates/arbiter-server/src/grpc/common/outbound.rs

@@ -1,10 +1,4 @@
-use crate::{
+use alloy::primitives::U256;
-    evm::{
-        PolicyError, VetError,
-        policies::{EvalViolation, SpecificMeaning},
-    },
-    grpc::Convert,
-};
 use arbiter_proto::proto::{
     evm::{
         EvmError as ProtoEvmError,
@@ -20,7 +14,13 @@ use arbiter_proto::proto::{
     },
 };
 
-use alloy::primitives::U256;
+use crate::{
+    evm::{
+        PolicyError, VetError,
+        policies::{EvalViolation, SpecificMeaning},
+    },
+    grpc::Convert,
+};
 
 fn u256_to_proto_bytes(value: U256) -> Vec<u8> {
     value.to_be_bytes::<32>().to_vec()
@@ -31,16 +31,16 @@ impl Convert for SpecificMeaning {
 
     fn convert(self) -> Self::Output {
         let kind = match self {
-            Self::EtherTransfer(meaning) => ProtoSpecificMeaningKind::EtherTransfer(
+            SpecificMeaning::EtherTransfer(meaning) => ProtoSpecificMeaningKind::EtherTransfer(
                 arbiter_proto::proto::shared::evm::EtherTransferMeaning {
                     to: meaning.to.to_vec(),
                     value: u256_to_proto_bytes(meaning.value),
                 },
             ),
-            Self::TokenTransfer(meaning) => ProtoSpecificMeaningKind::TokenTransfer(
+            SpecificMeaning::TokenTransfer(meaning) => ProtoSpecificMeaningKind::TokenTransfer(
                 arbiter_proto::proto::shared::evm::TokenTransferMeaning {
                     token: Some(ProtoTokenInfo {
-                        symbol: meaning.token.symbol.to_owned(),
+                        symbol: meaning.token.symbol.to_string(),
                         address: meaning.token.contract.to_vec(),
                         chain_id: meaning.token.chain,
                     }),
@@ -61,21 +61,25 @@ impl Convert for EvalViolation {
 
     fn convert(self) -> Self::Output {
         let kind = match self {
-            Self::InvalidTarget { target } => {
+            EvalViolation::InvalidTarget { target } => {
                 ProtoEvalViolationKind::InvalidTarget(target.to_vec())
             }
-            Self::GasLimitExceeded {
+            EvalViolation::GasLimitExceeded {
                 max_gas_fee_per_gas,
                 max_priority_fee_per_gas,
             } => ProtoEvalViolationKind::GasLimitExceeded(GasLimitExceededViolation {
                 max_gas_fee_per_gas: max_gas_fee_per_gas.map(u256_to_proto_bytes),
                 max_priority_fee_per_gas: max_priority_fee_per_gas.map(u256_to_proto_bytes),
             }),
-            Self::RateLimitExceeded => ProtoEvalViolationKind::RateLimitExceeded(()),
+            EvalViolation::RateLimitExceeded => ProtoEvalViolationKind::RateLimitExceeded(()),
-            Self::VolumetricLimitExceeded => ProtoEvalViolationKind::VolumetricLimitExceeded(()),
+            EvalViolation::VolumetricLimitExceeded => {
-            Self::InvalidTime => ProtoEvalViolationKind::InvalidTime(()),
+                ProtoEvalViolationKind::VolumetricLimitExceeded(())
-            Self::InvalidTransactionType => ProtoEvalViolationKind::InvalidTransactionType(()),
+            }
-            Self::MismatchingChainId { expected, actual } => {
+            EvalViolation::InvalidTime => ProtoEvalViolationKind::InvalidTime(()),
+            EvalViolation::InvalidTransactionType => {
+                ProtoEvalViolationKind::InvalidTransactionType(())
+            }
+            EvalViolation::MismatchingChainId { expected, actual } => {
                 ProtoEvalViolationKind::ChainIdMismatch(proto_eval_violation::ChainIdMismatch {
                     expected,
                     actual,
@@ -92,13 +96,13 @@ impl Convert for VetError {
 
     fn convert(self) -> Self::Output {
         let kind = match self {
-            Self::ContractCreationNotSupported => {
+            VetError::ContractCreationNotSupported => {
                 ProtoTransactionEvalErrorKind::ContractCreationNotSupported(())
             }
-            Self::UnsupportedTransactionType => {
+            VetError::UnsupportedTransactionType => {
                 ProtoTransactionEvalErrorKind::UnsupportedTransactionType(())
             }
-            Self::Evaluated(meaning, policy_error) => match policy_error {
+            VetError::Evaluated(meaning, policy_error) => match policy_error {
                 PolicyError::NoMatchingGrant => {
                     ProtoTransactionEvalErrorKind::NoMatchingGrant(NoMatchingGrantError {
                         meaning: Some(meaning.convert()),

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

@@ -1,20 +1,23 @@
-use crate::peers::{client::ClientConnection, operator::OperatorConnection};
 use arbiter_proto::{
     proto::{
         client::{ClientRequest, ClientResponse},
-        operator::{OperatorRequest, OperatorResponse},
+        user_agent::{UserAgentRequest, UserAgentResponse},
     },
     transport::grpc::GrpcBi,
 };
-
 use tokio_stream::wrappers::ReceiverStream;
 use tonic::{Request, Response, Status, async_trait};
 use tracing::info;
 
+use crate::{
+    actors::{client::ClientConnection, user_agent::UserAgentConnection},
+    grpc::user_agent::start,
+};
+
 mod request_tracker;
 
 pub mod client;
-pub mod operator;
+pub mod user_agent;
 
 mod common;
 
@@ -33,7 +36,7 @@ pub trait TryConvert {
 
 #[async_trait]
 impl arbiter_proto::proto::arbiter_service_server::ArbiterService for super::Server {
-    type OperatorStream = ReceiverStream<Result<OperatorResponse, Status>>;
+    type UserAgentStream = ReceiverStream<Result<UserAgentResponse, Status>>;
     type ClientStream = ReceiverStream<Result<ClientResponse, Status>>;
 
     #[tracing::instrument(level = "debug", skip(self))]
@@ -52,23 +55,23 @@ impl arbiter_proto::proto::arbiter_service_server::ArbiterService for super::Ser
     }
 
     #[tracing::instrument(level = "debug", skip(self))]
-    async fn operator(
+    async fn user_agent(
         &self,
-        request: Request<tonic::Streaming<OperatorRequest>>,
+        request: Request<tonic::Streaming<UserAgentRequest>>,
-    ) -> Result<Response<Self::OperatorStream>, Status> {
+    ) -> Result<Response<Self::UserAgentStream>, Status> {
         let req_stream = request.into_inner();
 
         let (bi, rx) = GrpcBi::from_bi_stream(req_stream);
 
-        tokio::spawn(operator::start(
+        tokio::spawn(start(
-            OperatorConnection {
+            UserAgentConnection {
                 db: self.context.db.clone(),
                 actors: self.context.actors.clone(),
             },
             bi,
         ));
 
-        info!(event = "connection established", "grpc.operator");
+        info!(event = "connection established", "grpc.user_agent");
 
         Ok(Response::new(rx))
     }

server/crates/arbiter-server/src/grpc/operator/vault.rs

@@ -1,60 +0,0 @@
-use crate::{
-    actors::vault::VaultState,
-    peers::operator::{OperatorSession, session::handlers::HandleQueryVaultState},
-};
-use arbiter_proto::{
-    proto::operator::{
-        operator_response::Payload as OperatorResponsePayload,
-        vault::{
-            self as proto_vault, request::Payload as VaultRequestPayload,
-            response::Payload as VaultResponsePayload,
-        },
-    },
-    proto::shared::VaultState as ProtoVaultState,
-};
-
-use kameo::actor::ActorRef;
-use tonic::Status;
-use tracing::warn;
-
-const fn wrap_vault_response(payload: VaultResponsePayload) -> OperatorResponsePayload {
-    OperatorResponsePayload::Vault(proto_vault::Response {
-        payload: Some(payload),
-    })
-}
-
-pub(super) async fn dispatch(
-    actor: &ActorRef<OperatorSession>,
-    req: proto_vault::Request,
-) -> Result<Option<OperatorResponsePayload>, Status> {
-    let Some(payload) = req.payload else {
-        return Err(Status::invalid_argument("Missing vault request payload"));
-    };
-
-    match payload {
-        VaultRequestPayload::QueryState(()) => handle_query_vault_state(actor).await,
-        VaultRequestPayload::Unseal(_) | VaultRequestPayload::Bootstrap(_) => {
-            Err(Status::permission_denied(
-                "Vault is already unsealed; unseal/bootstrap not permitted in session",
-            ))
-        }
-    }
-}
-
-async fn handle_query_vault_state(
-    actor: &ActorRef<OperatorSession>,
-) -> Result<Option<OperatorResponsePayload>, Status> {
-    let state = match actor.ask(HandleQueryVaultState {}).await {
-        Ok(VaultState::Unbootstrapped) => ProtoVaultState::Unbootstrapped,
-        Ok(VaultState::Sealed) => ProtoVaultState::Sealed,
-        Ok(VaultState::Bootstrapping) => ProtoVaultState::Boostrapping,
-        Ok(VaultState::Unsealed) => ProtoVaultState::Unsealed,
-        Err(err) => {
-            warn!(error = ?err, "Failed to query vault state");
-            ProtoVaultState::Error
-        }
-    };
-    Ok(Some(wrap_vault_response(VaultResponsePayload::State(
-        state.into(),
-    ))))
-}

server/crates/arbiter-server/src/grpc/operator/vault_gate.rs

@@ -1,79 +0,0 @@
-use super::auth::AuthTransportAdapter;
-use crate::{
-    grpc::TryConvert,
-    peers::operator::vault_gate::{self as vault_gate},
-};
-use arbiter_proto::transport::{Bi, Error as TransportError, Receiver, Sender};
-
-use async_trait::async_trait;
-use tonic::Status;
-use tracing::warn;
-
-mod inbound;
-mod outbound;
-
-#[async_trait]
-impl Receiver<vault_gate::Inbound> for AuthTransportAdapter<'_> {
-    async fn recv(&mut self) -> Option<vault_gate::Inbound> {
-        let request = match self.bi_mut().recv().await? {
-            Ok(request) => request,
-            Err(error) => {
-                warn!(
-                    ?error,
-                    "Failed to receive operator request during vault gate"
-                );
-                return None;
-            }
-        };
-
-        if let Err(err) = self.tracker_mut().request(request.id) {
-            let _ = self.bi_mut().send(Err(err)).await;
-            return None;
-        }
-
-        let Some(payload) = request.payload else {
-            let _ = self
-                .bi_mut()
-                .send(Err(Status::invalid_argument("Missing request payload")))
-                .await;
-            return None;
-        };
-
-        match payload.try_convert() {
-            Ok(inbound) => Some(inbound),
-            Err(status) => {
-                let _ = self.bi_mut().send(Err(status)).await;
-                None
-            }
-        }
-    }
-}
-
-#[async_trait]
-impl Sender<Result<vault_gate::Outbound, vault_gate::Error>> for AuthTransportAdapter<'_> {
-    async fn send(
-        &mut self,
-        item: Result<vault_gate::Outbound, vault_gate::Error>,
-    ) -> Result<(), TransportError> {
-        let outbound = match item {
-            Ok(outbound) => outbound,
-            Err(err) => {
-                warn!(?err, "vault gate produced transport-level error");
-                return self
-                    .bi_mut()
-                    .send(Err(Status::internal(err.to_string())))
-                    .await;
-            }
-        };
-
-        match outbound.try_convert() {
-            Ok(payload) => self.send_response_payload(payload).await,
-            Err(status) => self.bi_mut().send(Err(status)).await,
-        }
-    }
-}
-
-impl Bi<vault_gate::Inbound, Result<vault_gate::Outbound, vault_gate::Error>>
-    for AuthTransportAdapter<'_>
-{
-}

server/crates/arbiter-server/src/grpc/operator/vault_gate/inbound.rs

@@ -1,129 +0,0 @@
-use crate::{
-    grpc::{Convert, TryConvert},
-    peers::operator::vault_gate::{
-        self as vault_gate, HandleBootstrapEncryptedKey, HandleHandshake, HandleUnsealEncryptedKey,
-    },
-};
-use arbiter_proto::proto::operator::{
-    operator_request::Payload as OperatorRequestPayload,
-    vault::{
-        self as proto_vault,
-        bootstrap::{self as proto_bootstrap},
-        request::Payload as VaultRequestPayload,
-        unseal::{self as proto_unseal, request::Payload as UnsealRequestPayload},
-    },
-};
-
-use tonic::Status;
-
-impl TryConvert for OperatorRequestPayload {
-    type Output = vault_gate::Inbound;
-    type Error = Status;
-
-    fn try_convert(self) -> Result<vault_gate::Inbound, Status> {
-        match self {
-            Self::Vault(req) => req.try_convert(),
-            _ => Err(Status::permission_denied(
-                "Only vault operations are permitted before unsealing",
-            )),
-        }
-    }
-}
-
-impl TryConvert for proto_vault::Request {
-    type Output = vault_gate::Inbound;
-    type Error = Status;
-
-    fn try_convert(self) -> Result<vault_gate::Inbound, Status> {
-        self.payload
-            .ok_or_else(|| Status::invalid_argument("Missing vault request payload"))?
-            .try_convert()
-    }
-}
-
-impl TryConvert for VaultRequestPayload {
-    type Output = vault_gate::Inbound;
-    type Error = Status;
-
-    fn try_convert(self) -> Result<vault_gate::Inbound, Status> {
-        match self {
-            Self::QueryState(()) => Ok(vault_gate::Inbound::HandleVaultState),
-            Self::Unseal(req) => req.try_convert(),
-            Self::Bootstrap(req) => req.try_convert(),
-        }
-    }
-}
-
-impl TryConvert for proto_unseal::Request {
-    type Output = vault_gate::Inbound;
-    type Error = Status;
-
-    fn try_convert(self) -> Result<vault_gate::Inbound, Status> {
-        self.payload
-            .ok_or_else(|| Status::invalid_argument("Missing unseal request payload"))?
-            .try_convert()
-    }
-}
-
-impl TryConvert for UnsealRequestPayload {
-    type Output = vault_gate::Inbound;
-    type Error = Status;
-
-    fn try_convert(self) -> Result<vault_gate::Inbound, Status> {
-        match self {
-            Self::Start(start) => start.try_convert(),
-            Self::EncryptedKey(key) => Ok(key.convert()),
-        }
-    }
-}
-
-impl TryConvert for proto_unseal::UnsealStart {
-    type Output = vault_gate::Inbound;
-    type Error = Status;
-
-    fn try_convert(self) -> Result<vault_gate::Inbound, Status> {
-        let bytes = <[u8; 32]>::try_from(self.client_pubkey)
-            .map_err(|_| Status::invalid_argument("Invalid X25519 public key"))?;
-        Ok(vault_gate::Inbound::HandleHandshake(HandleHandshake {
-            client_pubkey: x25519_dalek::PublicKey::from(bytes),
-        }))
-    }
-}
-
-impl Convert for proto_unseal::UnsealEncryptedKey {
-    type Output = vault_gate::Inbound;
-
-    fn convert(self) -> vault_gate::Inbound {
-        vault_gate::Inbound::HandleUnsealEncryptedKey(HandleUnsealEncryptedKey {
-            nonce: self.nonce,
-            ciphertext: self.ciphertext,
-            associated_data: self.associated_data,
-        })
-    }
-}
-
-impl TryConvert for proto_bootstrap::Request {
-    type Output = vault_gate::Inbound;
-    type Error = Status;
-
-    fn try_convert(self) -> Result<vault_gate::Inbound, Status> {
-        self.encrypted_key
-            .ok_or_else(|| Status::invalid_argument("Missing bootstrap encrypted key"))?
-            .try_convert()
-    }
-}
-
-impl TryConvert for proto_bootstrap::BootstrapEncryptedKey {
-    type Output = vault_gate::Inbound;
-    type Error = Status;
-
-    fn try_convert(self) -> Result<vault_gate::Inbound, Status> {
-        Ok(vault_gate::Inbound::HandleBootstrapEncryptedKey(
-            HandleBootstrapEncryptedKey {
-                nonce: self.nonce,
-                ciphertext: self.ciphertext,
-                associated_data: self.associated_data,
-            },
-        ))
-    }
-}

server/crates/arbiter-server/src/grpc/operator/vault_gate/outbound.rs

@@ -1,116 +0,0 @@
-use crate::{
-    actors::vault::VaultState,
-    grpc::{Convert, TryConvert},
-    peers::operator::vault_gate::{self as vault_gate},
-};
-use arbiter_proto::proto::{
-    operator::{
-        operator_response::Payload as OperatorResponsePayload,
-        vault::{
-            self as proto_vault,
-            bootstrap::{self as proto_bootstrap, BootstrapResult as ProtoBootstrapResult},
-            response::Payload as VaultResponsePayload,
-            unseal::{
-                self as proto_unseal, UnsealResult as ProtoUnsealResult,
-                response::Payload as UnsealResponsePayload,
-            },
-        },
-    },
-    shared::VaultState as ProtoVaultState,
-};
-
-use tonic::Status;
-use tracing::warn;
-
-const fn wrap_vault_response(payload: VaultResponsePayload) -> OperatorResponsePayload {
-    OperatorResponsePayload::Vault(proto_vault::Response {
-        payload: Some(payload),
-    })
-}
-
-const fn wrap_unseal_response(payload: UnsealResponsePayload) -> OperatorResponsePayload {
-    wrap_vault_response(VaultResponsePayload::Unseal(proto_unseal::Response {
-        payload: Some(payload),
-    }))
-}
-
-fn wrap_bootstrap_response(result: ProtoBootstrapResult) -> OperatorResponsePayload {
-    wrap_vault_response(VaultResponsePayload::Bootstrap(proto_bootstrap::Response {
-        result: result.into(),
-    }))
-}
-
-impl Convert for VaultState {
-    type Output = OperatorResponsePayload;
-
-    fn convert(self) -> OperatorResponsePayload {
-        let proto_state = match self {
-            Self::Unbootstrapped => ProtoVaultState::Unbootstrapped,
-            Self::Bootstrapping => ProtoVaultState::Boostrapping,
-            Self::Sealed => ProtoVaultState::Sealed,
-            Self::Unsealed => ProtoVaultState::Unsealed,
-        };
-        wrap_vault_response(VaultResponsePayload::State(proto_state.into()))
-    }
-}
-
-impl Convert for vault_gate::HandshakeResponse {
-    type Output = OperatorResponsePayload;
-
-    fn convert(self) -> OperatorResponsePayload {
-        wrap_unseal_response(UnsealResponsePayload::Start(
-            proto_unseal::UnsealStartResponse {
-                server_pubkey: self.server_pubkey.as_bytes().to_vec(),
-            },
-        ))
-    }
-}
-
-impl TryConvert for vault_gate::Outbound {
-    type Output = OperatorResponsePayload;
-    type Error = Status;
-
-    fn try_convert(self) -> Result<OperatorResponsePayload, Status> {
-        match self {
-            Self::HandleVaultState(result) => result
-                .map_err(|err| {
-                    warn!(?err, "vault state query failed");
-                    Status::internal("Failed to query vault state")
-                })
-                .map(VaultState::convert),
-            Self::HandleHandshake(result) => result
-                .map_err(|err| {
-                    warn!(?err, "handshake failed");
-                    Status::internal("Failed to start unseal flow")
-                })
-                .map(vault_gate::HandshakeResponse::convert),
-            Self::HandleUnsealEncryptedKey(result) => {
-                let proto_result = match result {
-                    Ok(()) => ProtoUnsealResult::Success,
-                    Err(vault_gate::Error::InvalidKey) => ProtoUnsealResult::InvalidKey,
-                    Err(err) => {
-                        warn!(?err, "unseal failed");
-                        return Err(Status::internal("Failed to unseal vault"));
-                    }
-                };
-                Ok(wrap_unseal_response(UnsealResponsePayload::Result(
-                    proto_result.into(),
-                )))
-            }
-            Self::HandleBootstrapEncryptedKey(result) => {
-                let proto_result = match result {
-                    Ok(()) => ProtoBootstrapResult::Success,
-                    Err(vault_gate::Error::InvalidKey) => ProtoBootstrapResult::InvalidKey,
-                    Err(vault_gate::Error::AlreadyBootstrapped) => {
-                        ProtoBootstrapResult::AlreadyBootstrapped
-                    }
-                    Err(err) => {
-                        warn!(?err, "bootstrap failed");
-                        return Err(Status::internal("Failed to bootstrap vault"));
-                    }
-                };
-                Ok(wrap_bootstrap_response(proto_result))
-            }
-        }
-    }
-}

server/crates/arbiter-server/src/grpc/request_tracker.rs

@@ -1,12 +1,12 @@
 use tonic::Status;
 
 #[derive(Default)]
-pub(super) struct RequestTracker {
+pub struct RequestTracker {
     next_request_id: i32,
 }
 
 impl RequestTracker {
-    pub(super) fn request(&mut self, id: i32) -> Result<i32, Status> {
+    pub fn request(&mut self, id: i32) -> Result<i32, Status> {
         if id < self.next_request_id {
             return Err(Status::invalid_argument("Duplicate request id"));
         }
@@ -20,7 +20,7 @@ impl RequestTracker {
 
     // This is used to set the response id for auth responses, which need to match the request id of the auth challenge request.
     // -1 offset is needed because request() increments the next_request_id after returning the current request id.
-    pub(super) const fn current_request_id(&self) -> i32 {
+    pub fn current_request_id(&self) -> i32 {
         self.next_request_id - 1
     }
 }

server/crates/arbiter-server/src/grpc/user_agent.rs

@@ -1,29 +1,29 @@
-use crate::{
+use tokio::sync::mpsc;
-    grpc::request_tracker::RequestTracker,
+
-    peers::operator::{OutOfBand, OperatorConnection, OperatorSession},
-};
 use arbiter_proto::{
-    proto::operator::{
+    proto::user_agent::{
-        OperatorRequest, OperatorResponse,
+        UserAgentRequest, UserAgentResponse,
-        operator_request::Payload as OperatorRequestPayload,
+        user_agent_request::Payload as UserAgentRequestPayload,
-        operator_response::Payload as OperatorResponsePayload,
+        user_agent_response::Payload as UserAgentResponsePayload,
     },
     transport::{Error as TransportError, Receiver, Sender, grpc::GrpcBi},
 };
-
 use async_trait::async_trait;
-use kameo::actor::ActorRef;
+use kameo::actor::{ActorRef, Spawn as _};
-use tokio::sync::mpsc;
 use tonic::Status;
 use tracing::{error, info, warn};
 
+use crate::{
+    actors::user_agent::{OutOfBand, UserAgentConnection, UserAgentSession},
+    grpc::request_tracker::RequestTracker,
+};
+
 mod auth;
 mod evm;
 mod inbound;
 mod outbound;
 mod sdk_client;
 mod vault;
-mod vault_gate;
 
 pub struct OutOfBandAdapter(mpsc::Sender<OutOfBand>);
 
@@ -38,8 +38,8 @@ impl Sender<OutOfBand> for OutOfBandAdapter {
 }
 
 async fn dispatch_loop(
-    mut bi: GrpcBi<OperatorRequest, OperatorResponse>,
+    mut bi: GrpcBi<UserAgentRequest, UserAgentResponse>,
-    actor: ActorRef<OperatorSession>,
+    actor: ActorRef<UserAgentSession>,
     mut receiver: mpsc::Receiver<OutOfBand>,
     mut request_tracker: RequestTracker,
 ) {
@@ -53,7 +53,7 @@ async fn dispatch_loop(
 
                 let payload = sdk_client::out_of_band_payload(oob);
 
-                if bi.send(Ok(OperatorResponse { id: None, payload: Some(payload) })).await.is_err() {
+                if bi.send(Ok(UserAgentResponse { id: None, payload: Some(payload) })).await.is_err() {
                     return;
                 }
             }
@@ -64,7 +64,7 @@ async fn dispatch_loop(
                 let conn = match message {
                     Ok(conn) => conn,
                     Err(err) => {
-                        warn!(error = ?err, "Failed to receive operator request");
+                        warn!(error = ?err, "Failed to receive user agent request");
                         return;
                     }
                 };
@@ -78,13 +78,13 @@ async fn dispatch_loop(
                 };
 
                 let Some(payload) = conn.payload else {
-                    let _ = bi.send(Err(Status::invalid_argument("Missing operator request payload"))).await;
+                    let _ = bi.send(Err(Status::invalid_argument("Missing user-agent request payload"))).await;
                     return;
                 };
 
                 match dispatch_inner(&actor, payload).await {
                     Ok(Some(response)) => {
-                        if bi.send(Ok(OperatorResponse {
+                        if bi.send(Ok(UserAgentResponse {
                             id: Some(request_id),
                             payload: Some(response),
                         })).await.is_err() {
@@ -93,7 +93,7 @@ async fn dispatch_loop(
                     }
                     Ok(None) => {}
                     Err(status) => {
-                        error!(?status, "Failed to process operator request");
+                        error!(?status, "Failed to process user agent request");
                         let _ = bi.send(Err(status)).await;
                         return;
                     }
@@ -104,42 +104,41 @@ async fn dispatch_loop(
 }
 
 async fn dispatch_inner(
-    actor: &ActorRef<OperatorSession>,
+    actor: &ActorRef<UserAgentSession>,
-    payload: OperatorRequestPayload,
+    payload: UserAgentRequestPayload,
-) -> Result<Option<OperatorResponsePayload>, Status> {
+) -> Result<Option<UserAgentResponsePayload>, Status> {
     match payload {
-        OperatorRequestPayload::Vault(req) => vault::dispatch(actor, req).await,
+        UserAgentRequestPayload::Vault(req) => vault::dispatch(actor, req).await,
-        OperatorRequestPayload::Evm(req) => evm::dispatch(actor, req).await,
+        UserAgentRequestPayload::Evm(req) => evm::dispatch(actor, req).await,
-        OperatorRequestPayload::SdkClient(req) => sdk_client::dispatch(actor, req).await,
+        UserAgentRequestPayload::SdkClient(req) => sdk_client::dispatch(actor, req).await,
-        OperatorRequestPayload::Auth(..) => {
+        UserAgentRequestPayload::Auth(..) => {
-            warn!("Unsupported post-auth operator auth request");
+            warn!("Unsupported post-auth user agent auth request");
-            Err(Status::invalid_argument("Unsupported operator request"))
+            Err(Status::invalid_argument("Unsupported user-agent request"))
         }
     }
 }
 
 pub async fn start(
-    mut conn: OperatorConnection,
+    mut conn: UserAgentConnection,
-    mut bi: GrpcBi<OperatorRequest, OperatorResponse>,
+    mut bi: GrpcBi<UserAgentRequest, UserAgentResponse>,
 ) {
     let mut request_tracker = RequestTracker::default();
 
+    let pubkey = match auth::start(&mut conn, &mut bi, &mut request_tracker).await {
+        Ok(pubkey) => pubkey,
+        Err(e) => {
+            warn!(error = ?e, "Authentication failed");
+            return;
+        }
+    };
+
     let (oob_sender, oob_receiver) = mpsc::channel(16);
     let oob_adapter = OutOfBandAdapter(oob_sender);
 
-    let actor = {
+    let actor = UserAgentSession::spawn(UserAgentSession::new(conn, Box::new(oob_adapter)));
-        let transport = auth::AuthTransportAdapter::new(&mut bi, &mut request_tracker);
+    let actor_for_cleanup = actor.clone();
-        match crate::peers::operator::start(&mut conn, transport, Box::new(oob_adapter)).await {
-            Ok(actor) => actor,
-            Err(e) => {
-                warn!(error = ?e, "Operator connection failed");
-                return;
-            }
-        }
-    };
 
-    info!("Operator session established");
+    info!(?pubkey, "User authenticated successfully");
-
+    dispatch_loop(bi, actor, oob_receiver, request_tracker).await;
-    dispatch_loop(bi, actor.clone(), oob_receiver, request_tracker).await;
+    actor_for_cleanup.kill();
-    actor.kill();
 }

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

@@ -1,32 +1,35 @@
-use crate::{grpc::request_tracker::RequestTracker, peers::operator::auth};
 use arbiter_crypto::authn;
 use arbiter_proto::{
-    proto::operator::{
+    proto::user_agent::{
-        OperatorRequest, OperatorResponse,
+        UserAgentRequest, UserAgentResponse,
         auth::{
             self as proto_auth, AuthChallenge as ProtoAuthChallenge,
             AuthChallengeRequest as ProtoAuthChallengeRequest,
             AuthChallengeSolution as ProtoAuthChallengeSolution, AuthResult as ProtoAuthResult,
             request::Payload as AuthRequestPayload, response::Payload as AuthResponsePayload,
         },
-        operator_request::Payload as OperatorRequestPayload,
+        user_agent_request::Payload as UserAgentRequestPayload,
-        operator_response::Payload as OperatorResponsePayload,
+        user_agent_response::Payload as UserAgentResponsePayload,
     },
     transport::{Bi, Error as TransportError, Receiver, Sender, grpc::GrpcBi},
 };
-
 use async_trait::async_trait;
 use tonic::Status;
 use tracing::warn;
 
-pub(super) struct AuthTransportAdapter<'a> {
+use crate::{
-    pub(super) bi: &'a mut GrpcBi<OperatorRequest, OperatorResponse>,
+    actors::user_agent::{UserAgentConnection, auth},
-    pub(super) request_tracker: &'a mut RequestTracker,
+    grpc::request_tracker::RequestTracker,
+};
+
+pub struct AuthTransportAdapter<'a> {
+    bi: &'a mut GrpcBi<UserAgentRequest, UserAgentResponse>,
+    request_tracker: &'a mut RequestTracker,
 }
 
 impl<'a> AuthTransportAdapter<'a> {
-    pub(super) const fn new(
+    pub fn new(
-        bi: &'a mut GrpcBi<OperatorRequest, OperatorResponse>,
+        bi: &'a mut GrpcBi<UserAgentRequest, UserAgentResponse>,
         request_tracker: &'a mut RequestTracker,
     ) -> Self {
         Self {
@@ -35,32 +38,16 @@ impl<'a> AuthTransportAdapter<'a> {
         }
     }
 
-    pub(super) const fn bi_mut(&mut self) -> &mut GrpcBi<OperatorRequest, OperatorResponse> {
+    async fn send_user_agent_response(
-        self.bi
-    }
-
-    pub(super) const fn tracker_mut(&mut self) -> &mut RequestTracker {
-        self.request_tracker
-    }
-
-    pub(super) async fn send_response_payload(
-        &mut self,
-        payload: OperatorResponsePayload,
-    ) -> Result<(), TransportError> {
-        self.bi
-            .send(Ok(OperatorResponse {
-                id: Some(self.request_tracker.current_request_id()),
-                payload: Some(payload),
-            }))
-            .await
-    }
-
-    async fn send_operator_response(
         &mut self,
         payload: AuthResponsePayload,
     ) -> Result<(), TransportError> {
-        self.send_response_payload(OperatorResponsePayload::Auth(proto_auth::Response {
+        self.bi
+            .send(Ok(UserAgentResponse {
+                id: Some(self.request_tracker.current_request_id()),
+                payload: Some(UserAgentResponsePayload::Auth(proto_auth::Response {
                     payload: Some(payload),
+                })),
             }))
             .await
     }
@@ -74,15 +61,8 @@ impl Sender<Result<auth::Outbound, auth::Error>> for AuthTransportAdapter<'_> {
     ) -> Result<(), TransportError> {
         use auth::{Error, Outbound};
         let payload = match item {
-            Ok(Outbound::AuthChallenge { challenge }) => {
+            Ok(Outbound::AuthChallenge { nonce }) => {
-                AuthResponsePayload::Challenge(ProtoAuthChallenge {
+                AuthResponsePayload::Challenge(ProtoAuthChallenge { nonce })
-                    timestamp_nanos: challenge
-                        .timestamp
-                        .timestamp_nanos_opt()
-                        .expect("timestamp within range")
-                        as u64,
-                    random: challenge.nonce.to_vec(),
-                })
             }
             Ok(Outbound::AuthSuccess) => {
                 AuthResponsePayload::Result(ProtoAuthResult::Success.into())
@@ -107,7 +87,7 @@ impl Sender<Result<auth::Outbound, auth::Error>> for AuthTransportAdapter<'_> {
             }
         };
 
-        self.send_operator_response(payload).await
+        self.send_user_agent_response(payload).await
     }
 }
 
@@ -117,7 +97,7 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
         let request = match self.bi.recv().await? {
             Ok(request) => request,
             Err(error) => {
-                warn!(error = ?error, "Failed to receive operator auth request");
+                warn!(error = ?error, "Failed to receive user agent auth request");
                 return None;
             }
         };
@@ -133,16 +113,16 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
         let Some(payload) = request.payload else {
             warn!(
                 event = "received request with empty payload",
-                "grpc.operator.auth_adapter"
+                "grpc.useragent.auth_adapter"
             );
             return None;
         };
 
-        let OperatorRequestPayload::Auth(auth_request) = payload else {
+        let UserAgentRequestPayload::Auth(auth_request) = payload else {
             let _ = self
                 .bi
                 .send(Err(Status::invalid_argument(
-                    "Unsupported operator auth request",
+                    "Unsupported user-agent auth request",
                 )))
                 .await;
             return None;
@@ -151,7 +131,7 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
         let Some(payload) = auth_request.payload else {
             warn!(
                 event = "received auth request with empty payload",
-                "grpc.operator.auth_adapter"
+                "grpc.useragent.auth_adapter"
             );
             return None;
         };
@@ -160,11 +140,12 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
             AuthRequestPayload::ChallengeRequest(ProtoAuthChallengeRequest {
                 pubkey,
                 bootstrap_token,
+                key_type: _,
             }) => {
                 let Ok(pubkey) = authn::PublicKey::try_from(pubkey.as_slice()) else {
                     warn!(
                         event = "received request with invalid public key",
-                        "grpc.operator.auth_adapter"
+                        "grpc.useragent.auth_adapter"
                     );
                     return None;
                 };
@@ -182,3 +163,12 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
 }
 
 impl Bi<auth::Inbound, Result<auth::Outbound, auth::Error>> for AuthTransportAdapter<'_> {}
+
+pub async fn start(
+    conn: &mut UserAgentConnection,
+    bi: &mut GrpcBi<UserAgentRequest, UserAgentResponse>,
+    request_tracker: &mut RequestTracker,
+) -> Result<authn::PublicKey, auth::Error> {
+    let transport = AuthTransportAdapter::new(bi, request_tracker);
+    auth::authenticate(conn, transport).await
+}

server/crates/arbiter-server/src/grpc/user_agent/evm.rs

@@ -1,17 +1,3 @@
-use crate::{
-    grpc::{
-        Convert, TryConvert,
-        common::inbound::{RawEvmAddress, RawEvmTransaction},
-    },
-    peers::operator::{
-        OperatorSession,
-        session::handlers::{
-            GrantMutationError, HandleEvmWalletCreate, HandleEvmWalletList, HandleGrantCreate,
-            HandleGrantDelete, HandleGrantList, HandleSignTransaction,
-            SignTransactionError as SessionSignTransactionError,
-        },
-    },
-};
 use arbiter_proto::proto::{
     evm::{
         EvmError as ProtoEvmError, EvmGrantCreateRequest, EvmGrantCreateResponse,
@@ -24,36 +10,50 @@ use arbiter_proto::proto::{
         wallet_create_response::Result as WalletCreateResult,
         wallet_list_response::Result as WalletListResult,
     },
-    operator::{
+    user_agent::{
         evm::{
             self as proto_evm, SignTransactionRequest as ProtoSignTransactionRequest,
             request::Payload as EvmRequestPayload, response::Payload as EvmResponsePayload,
         },
-        operator_response::Payload as OperatorResponsePayload,
+        user_agent_response::Payload as UserAgentResponsePayload,
     },
 };
-
 use kameo::actor::ActorRef;
 use tonic::Status;
 use tracing::warn;
 
-const fn wrap_evm_response(payload: EvmResponsePayload) -> OperatorResponsePayload {
+use crate::{
-    OperatorResponsePayload::Evm(proto_evm::Response {
+    actors::user_agent::{
+        UserAgentSession,
+        session::connection::{
+            GrantMutationError, HandleEvmWalletCreate, HandleEvmWalletList, HandleGrantCreate,
+            HandleGrantDelete, HandleGrantList, HandleSignTransaction,
+            SignTransactionError as SessionSignTransactionError,
+        },
+    },
+    grpc::{
+        Convert, TryConvert,
+        common::inbound::{RawEvmAddress, RawEvmTransaction},
+    },
+};
+
+fn wrap_evm_response(payload: EvmResponsePayload) -> UserAgentResponsePayload {
+    UserAgentResponsePayload::Evm(proto_evm::Response {
         payload: Some(payload),
     })
 }
 
 pub(super) async fn dispatch(
-    actor: &ActorRef<OperatorSession>,
+    actor: &ActorRef<UserAgentSession>,
     req: proto_evm::Request,
-) -> Result<Option<OperatorResponsePayload>, Status> {
+) -> Result<Option<UserAgentResponsePayload>, Status> {
     let Some(payload) = req.payload else {
         return Err(Status::invalid_argument("Missing EVM request payload"));
     };
 
     match payload {
-        EvmRequestPayload::WalletCreate(()) => handle_wallet_create(actor).await,
+        EvmRequestPayload::WalletCreate(_) => handle_wallet_create(actor).await,
-        EvmRequestPayload::WalletList(()) => handle_wallet_list(actor).await,
+        EvmRequestPayload::WalletList(_) => handle_wallet_list(actor).await,
         EvmRequestPayload::GrantCreate(req) => handle_grant_create(actor, req).await,
         EvmRequestPayload::GrantDelete(req) => handle_grant_delete(actor, req).await,
         EvmRequestPayload::GrantList(_) => handle_grant_list(actor).await,
@@ -62,8 +62,8 @@ pub(super) async fn dispatch(
 }
 
 async fn handle_wallet_create(
-    actor: &ActorRef<OperatorSession>,
+    actor: &ActorRef<UserAgentSession>,
-) -> Result<Option<OperatorResponsePayload>, Status> {
+) -> Result<Option<UserAgentResponsePayload>, Status> {
     let result = match actor.ask(HandleEvmWalletCreate {}).await {
         Ok((wallet_id, address)) => WalletCreateResult::Wallet(WalletEntry {
             id: wallet_id,
@@ -82,15 +82,15 @@ async fn handle_wallet_create(
 }
 
 async fn handle_wallet_list(
-    actor: &ActorRef<OperatorSession>,
+    actor: &ActorRef<UserAgentSession>,
-) -> Result<Option<OperatorResponsePayload>, Status> {
+) -> Result<Option<UserAgentResponsePayload>, Status> {
     let result = match actor.ask(HandleEvmWalletList {}).await {
         Ok(wallets) => WalletListResult::Wallets(WalletList {
             wallets: wallets
                 .into_iter()
                 .map(|(id, address)| WalletEntry {
                     address: address.to_vec(),
-                    id: id.to_raw(),
+                    id,
                 })
                 .collect(),
         }),
@@ -107,8 +107,8 @@ async fn handle_wallet_list(
 }
 
 async fn handle_grant_list(
-    actor: &ActorRef<OperatorSession>,
+    actor: &ActorRef<UserAgentSession>,
-) -> Result<Option<OperatorResponsePayload>, Status> {
+) -> Result<Option<UserAgentResponsePayload>, Status> {
     let result = match actor.ask(HandleGrantList {}).await {
         Ok(grants) => EvmGrantListResult::Grants(EvmGrantList {
             grants: grants
@@ -134,9 +134,9 @@ async fn handle_grant_list(
 }
 
 async fn handle_grant_create(
-    actor: &ActorRef<OperatorSession>,
+    actor: &ActorRef<UserAgentSession>,
     req: EvmGrantCreateRequest,
-) -> Result<Option<OperatorResponsePayload>, Status> {
+) -> Result<Option<UserAgentResponsePayload>, Status> {
     let basic = req
         .shared
         .ok_or_else(|| Status::invalid_argument("Missing shared grant settings"))?
@@ -164,9 +164,9 @@ async fn handle_grant_create(
 }
 
 async fn handle_grant_delete(
-    actor: &ActorRef<OperatorSession>,
+    actor: &ActorRef<UserAgentSession>,
     req: EvmGrantDeleteRequest,
-) -> Result<Option<OperatorResponsePayload>, Status> {
+) -> Result<Option<UserAgentResponsePayload>, Status> {
     let result = match actor
         .ask(HandleGrantDelete {
             grant_id: req.grant_id,
@@ -190,9 +190,9 @@ async fn handle_grant_delete(
 }
 
 async fn handle_sign_transaction(
-    actor: &ActorRef<OperatorSession>,
+    actor: &ActorRef<UserAgentSession>,
     req: ProtoSignTransactionRequest,
-) -> Result<Option<OperatorResponsePayload>, Status> {
+) -> Result<Option<UserAgentResponsePayload>, Status> {
     let request = req
         .request
         .ok_or_else(|| Status::invalid_argument("Missing sign transaction request"))?;