Apply #[rpc_requests(message = SecretMessage)] to SecretProtocol enum with
#[rpc(tx=oneshot::Sender<Result<T, SecretServiceError>>)] and #[wrap] attributes
on each variant. Add SecretServiceActor that wraps SecretServiceHandle and
processes SecretMessage variants via mpsc channel. Update DerivedKey
serialization to use is_human_readable() so postcard preserves private_key
bytes while JSON redacts them. Add Serialize/Deserialize to SecretServiceError
for irpc wire format compatibility. Add tokio dependency for actor runtime.
Implement KeyCache in cache.rs with CachedKey (Zeroize-protected),
CacheConfig (TTL + max_entries), and lazy eviction. Wire cache into
SecretServiceInner: derive_* methods check cache before re-deriving,
Lock clears and zeroizes all cache entries, encrypt/decrypt use
cached encryption key. Per ADR-038 and OQ-SVC-04.
Implements deterministic password derivation using SLIP-0010 at the
given path. derive_password returns raw truncated key bytes;
derive_password_string returns Base64url-encoded (no padding) string.
Both require unlocked state (ServiceLocked if locked). Includes unit
tests for determinism, different paths, length truncation, locked
error, and Base64url encoding.
Per ADR-038, DerivedKey.private_key now derives Zeroize with #[zeroize(drop)]
ensuring sensitive key material is zeroized before deallocation. DerivedKey
is now move-only (no Clone), and JSON/debug output redacts private_key as
"[REDACTED]". Deserialization still works for postcard/irpc wire format.
Also fixes clippy needless_borrows_for_generic_args in encryption.rs and
applies cargo fmt to existing code.
Add module-level documentation explaining that the salt field is reserved
for Phase B KDF-based key rotation. Add doc comment on the salt field
clarifying it is not used in v1 key derivation. Add TODO(Phase B) comment
on salt generation in encrypt().
- Add irpc (0.16) and irpc-derive (0.16) as workspace dependencies
- Add irpc, irpc-derive, and secp256k1 (optional) to alknet-secret Cargo.toml
- Clarify encryption-salt-kdf task: Option B (document salt as reserved) is the
chosen path per spec update, removing Option A acceptance criteria
- Update irpc-secret-protocol-integration task with concrete irpc crate details:
real crate on crates.io v0.16, #[rpc_requests] macro, workspace config,
AuthProtocol pattern reference, DerivedKey serialization considerations
- Fix secp256k1-ethereum-derivation task: correct crate name is secp256k1
(not libsecp256k1), add version pin 0.29
Create the alknet-secret crate with BIP39 mnemonic generation, SLIP-0010
Ed25519 HD key derivation, AES-256-GCM encryption, and SecretProtocol
irpc service definition. This is Phase 3.1 from the integration plan.
Architecture changes:
- Promote secret-service.md to reviewed status with full spec format
(crate structure, public API, security model, phase progression,
ADR/OQ cross-references, wire format compatibility section)
- Add ADR-038 (seed lifecycle and memory security): zeroize for v1,
mlock deferred to Phase B
- Add OQ-SEC-01 (mlock/VirtualLock for seed RAM) to open-questions.md
- Update README.md with ADR-038 and secret-service status
Crate structure:
- src/mnemonic.rs: BIP39 phrase generation, validation, seed derivation
- src/derivation.rs: SLIP-0010 HD key derivation, path constants (74')
- src/encryption.rs: AES-256-GCM encrypt/decrypt, EncryptedData type
- src/protocol.rs: SecretProtocol irpc enum, DerivedKey, KeyType
- src/service.rs: SecretServiceHandle with Unlock/Lock lifecycle
- 40 passing tests (unit + integration + doc)
