ADR-0074 — Provider Credential Storage and Proxy Retrieval PathCopy Anchor Link

StatusCopy Anchor Link

Accepted (Milestone 4.A.5)

ContextCopy Anchor Link

Platform LLM keys are process env vars on the proxy. Multi-tenant BYO keys need org-scoped storage, encryption at rest, validate-before-store, and a fail-closed retrieval path that does not mutate shared provider clients.

Discovery found no in-repo AES/envelope helper (ADR-0010 deferred crypto) and no KMS/Vault application integration. Sketch ADR-0046 was already assigned to the embedder.

DecisionCopy Anchor Link

1. Stdlib AES-256-GCM envelope in packages/crypto only (Go). KEK from IBEX_CREDENTIALS_MASTER_KEY (base64 32 bytes), Auth-only.
2. Column layout: ciphertext, wrapped_dek, encryption_key_id, key_hint (each sealed blob is nonce||GCM ciphertext+tag).
3. Auth owns plaintext at rest: Create/Get/List/Delete gRPC; Management API never persists ciphertext or returns secrets.
4. Validate-before-store in Management API (Python httpx probe) → INVALID_CREDENTIAL (422).
5. Proxy: per-request GetProviderCredential + 30s cache; optional provider.Request.APIKeyOverride; no-row → platform default; row + Auth error → fail closed.
6. Separate POST .../validate deferred to a follow-up.

ConsequencesCopy Anchor Link

• Production Auth requires IBEX_CREDENTIALS_MASTER_KEY.
• Proxy boot path for platform keys unchanged when no credential rows exist.
• Multi-key rotation / Vault / Bedrock IAM remain out of scope.