The vault uses SLIP-0010 HD derivation from the BIP39 seed for the
AES-256-GCM encryption key, not PBKDF2. This replaces the TypeScript
predecessor's (@alkdev/storage/src/graphs/crypto.ts) PBKDF2-based
approach.
Key decisions:
- HD derivation at m/74'/2'/0'/0' produces the encryption key
- PBKDF2 is not implemented in the vault; no password-based derivation
- salt field is unused in v2 (wire-format compat only)
- key_version=1 reserved for TS PBKDF2 data; key_version=2 for vault HD
- TS-encrypted data requires one-time migration to v2
- CURRENT_KEY_VERSION changes from 1 to 2 (source drift flagged)
OQ-20 resolved: the encryption key derivation method is locked. OQ-22
(key rotation workflow) remains open but does not block implementation.
Spec the vault crate from its existing implementation. The vault is
stable (implementation exists); this spec documents what IS so the
implementation-sync agent can reconcile source drift.
New spec documents (crates/vault/):
- README.md — crate index, security constraints, public API
- mnemonic-derivation.md — BIP39, SLIP-0010, BIP-0032, derivation paths
- encryption.md — AES-256-GCM, EncryptedData, key versioning, salt
- service.md — VaultServiceHandle lifecycle, actor dispatch, cache
- protocol.md — VaultProtocol irpc messages, DerivedKey redaction
New ADRs:
- ADR-018: Vault as standalone crate (zero alknet deps; own types/errors)
- ADR-019: Vault assembly-layer-only access (CLI is sole caller)
New open questions:
- OQ-20: Salt/KDF Phase B (open, low priority — salt field reserved)
- OQ-21: Remote vault administration (deferred — needs ADR if ever needed)
- OQ-22: Key rotation mechanism (open, low priority — workflow not specced)
Spec-vs-source drift explicitly flagged (for the sync agent):
- rand::random() used for IVs instead of OsRng (security-critical)
- unwrap() on every RwLock acquisition (must use unwrap_or_else)
- ADR-038 / OQ-SVC-03 references in source comments are stale (old numbering)
- VaultServiceActor::spawn returns a non-functional second actor (source bug)
- KeyVersionMismatch error variant is defined but unused in v1
Critical:
- operation-registry: remove stale duplicate OperationEnv impl that
propagated parent.metadata through composition (violated ADR-014);
collapse to one canonical block with metadata: HashMap::new()
- operation-registry: fix request_id collision — format!("env-{name}")
produced identical IDs across concurrent invocations, corrupting
PendingRequestMap correlation and the abort-cascade tree (ADR-016)
- operation-registry + ADR-015: fix OperationContext.internal visibility —
pub field let handlers mark their own call internal (privilege
escalation per ADR-015); change to pub(crate) with pub fn is_internal
Warnings:
- core-types: add Connection::set_identity/identity (OQ-11) to the
Connection type spec — was specified in auth.md but missing from the
type definition
- operation-registry: add Capabilities: Clone design note — invoke()
clones capabilities through composition; explicit security implication
- call-protocol: add CallAdapter root OperationContext construction
example showing internal: false wire path, complementing
OperationEnv::invoke() internal: true composition path
- overview: remove alknet/agent from ALPN registry — agent is a future
consumer of alknet-call (call-protocol operations), not a separate ALPN
- call-protocol: clarify call.requested payload schema and the
leading-slash convention (wire operationId has slash, registry name
does not)
Suggestions:
- operation-registry: cross-reference ResponseEnvelope definition
- core-types: add StreamError to HandlerError mapping table
Address security review findings by adding explicit constraints to specs
and implementation specialist role:
Architectural constraints (spec updates):
- metadata does not propagate through OperationEnv::invoke() — fresh
HashMap for nested calls, closes the back-door leak channel where a
handler that puts a secret in metadata would leak it to children and
across from_call to remote nodes (ADR-014)
- Config reload must be authenticated/local-only — malicious reload =
root-equivalent privilege grant (config.md)
- from_call trust is transitive — scoped env bounds reachability, not
what the remote op does (operation-registry.md)
- Token entropy ≥128 bits — prefix is lookup aid not secret, offline
hash verification requires high-entropy tokens (auth.md)
Implementation constraints (auth.md security constraints section + role spec):
- OsRng for cryptographic nonces (AES-GCM IV reuse is catastrophic)
- CachedKey derives Zeroize/ZeroizeOnDrop (no secrets in freed heap)
- No unwrap()/expect() outside tests (poisoned lock recovery, not crash)
- Implementation specialist role spec updated with all four constraints
OQ-11 (handler-level auth observability): Option B — handlers store
resolved identity on Connection via set_identity. Two identity scopes:
connection-level (observability, write-once-read-many) and per-request
(ACL, on OperationContext). Per-request takes precedence for ACL;
connection-level is for logging/audit only.
OQ-19 (session-scoped registries): Protocol doesn't need changes.
OperationEnv must remain a trait (not concrete) to enable session-overlay
pattern. Three-tier registry: core (static, External+Internal), session
(dynamic, Internal-only), promotion (curated review). Documented as
implementation guard in operation-registry.md.
All 19 open questions are now resolved. No open one-way or two-way doors
remain. The architecture is ready for review and implementation.
ADR-017 locks the client/adapter architecture:
- CallClient opens QUIC connections, shares dispatch loop with CallAdapter
- Connection direction independent of call direction (both sides can call)
- from_call adapter: discovers remote ops via services/list + services/schema,
registers with forwarding handlers (same pattern as from_openapi/from_mcp)
- to_openapi/to_mcp: project local ops to external protocols
- OperationAdapter trait: produces (OperationSpec, Handler) pairs
- Cross-node call tree: abort cascade propagates through from_call handlers
- Credentials from capabilities (ADR-014), adapter ops Internal by default (ADR-015)
The dispatch POC at /workspace/@alkdev/dispatch demonstrated head/worker over
SSH+axum; under the call protocol it's cross-node composition via from_call.
Connection topology (who advertises, who opens) is independent of call
direction — runner pattern, dispatch pattern, and P2P all work.
Document the three-tier registry model (core/session/promotion) and the
self-improving agent workflow where agents write their own operations in
a quickjs sandbox. The POC at /workspace/toolEnv demonstrated the sandbox
mechanism (quickjs in Deno web workers, proxy-based env bridge via
postMessage) but exposed the full registry to the sandbox — the security
gap that OQ-18's scoped composition env addresses.
The call protocol doesn't need changes: the OperationEnv trait is the
composition point, and a session-scoped env wraps the global env (session
registry first, fall through to global). The one-way door this OQ guards
against: making OperationEnv concrete instead of a trait, or hardcoding
the global registry into the dispatch path, would close the session-overlay
pattern. Session-scoped operations are always Internal, run under the
handler's identity, and are ephemeral. Promotion to core requires curation
review (architect role with promote scope).
The abort cascade and privilege model are call protocol semantics that
every consumer inherits — NAPI adapter, Python adapter, agent service, and
any future service speaking the EventEnvelope wire format. Framing them as
'needs agent crate in view' let a single consumer's timeline gate a
protocol-level decision. The agent use case is a useful test case for edge
cases, but the decisions belong to the call protocol.
The 'trusted' flag on OperationContext was the wrong word — it implies a
trust decision was made, but what actually happens is the call originated
internally (from composition) not externally (from the wire). Renamed to
'internal' with clarified semantics: internal calls switch authority
context to the handler's identity, not skip ACL. This prevents the
privilege escalation vector where composition with 'trusted: true' bypassed
all access control (buggy handler + parameterized dispatch).
- Rename trusted -> internal across operation-registry.md, ADR-014
- Update OperationContext field description and LocalOperationEnv code
- Add OQ-17: abort cascade for nested calls (call.aborted cascades to
descendants, default abort-dependents, continue-running opt-in). One-way
door on the protocol event schema; mechanism is a two-way door.
- Add OQ-18: privilege model and authority context (internal = authority
switch not ACL skip, External/Internal operation visibility, scoped
composition env + handler identity). Needs agent crate in view.
- Add abort cascade section and constraint to call-protocol.md
- Update crates/call/README.md with OQ-17, OQ-18, and two new design principles
- Update architecture README.md with OQ-17, OQ-18
Resolve the contradiction between ADR-008's "capability source" model
and operation-registry.md showing vault operations on the wire. ADR-014
establishes: vault is assembly-layer only, capabilities carry outbound
credentials (distinct from inbound identity), call protocol carries no
secret material, adapters take credential sources not static tokens.
- Add ADR-014 (Secret Material Flow and Capability Injection)
- Remove vault/derive, vault/unlock, vault/decrypt from call protocol
registration examples and all spec examples
- Add Capabilities field to OperationContext, propagate through
LocalOperationEnv nested calls
- Add Capability Injection section to operation-registry.md
- Add no-secret-material wire constraint to call-protocol.md
- Add streaming subscribe example (LLM chat with Vercel UI chunks)
- Add Security Model section to overview.md (identity vs capabilities)
- Trim WASM treatment from ~20 lines to a design-constraint note
- Add OQ-16 (resolved: no vault ops on wire), update OQ-08, OQ-15
- Update ADR-003, ADR-008, ADR-013 to remove stale "via call protocol"
vault references