Kyle Isom
64d921827e
Implement a two-level key hierarchy: the MEK now wraps per-engine DEKs stored in a new barrier_keys table, rather than encrypting all barrier entries directly. A v2 ciphertext format (0x02) embeds the key ID so the barrier can resolve which DEK to use on decryption. v1 ciphertext remains supported for backward compatibility. Key changes: - crypto: EncryptV2/DecryptV2/ExtractKeyID for v2 ciphertext with key IDs - barrier: key registry (CreateKey, RotateKey, ListKeys, MigrateToV2, ReWrapKeys) - seal: RotateMEK re-wraps DEKs without re-encrypting data - engine: Mount auto-creates per-engine DEK - REST + gRPC: barrier/keys, barrier/rotate-mek, barrier/rotate-key, barrier/migrate - proto: BarrierService (v1 + v2) with ListKeys, RotateMEK, RotateKey, Migrate - db: migration v2 adds barrier_keys table Also includes: security audit report, CSRF protection, engine design specs (sshca, transit, user), path-bound AAD migration tool, policy engine enhancements, and ARCHITECTURE.md updates. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Metacrypt
Metacrypt is a cryptographic service for the Metacircular platform. It provides an encrypted secrets barrier and pluggable cryptographic engines (CA/PKI, SSH CA, transit encryption, user-to-user encryption) over a gRPC and HTTPS API. Authentication is delegated to MCIAS.
It operates using a seal/unseal model similar to HashiCorp Vault: the service starts sealed on every boot and must be unlocked with a password before cryptographic operations are available.
Quick Start
Prerequisites
- Go 1.23+
- A running MCIAS instance
- TLS certificate and key for the server
Build
make metacrypt metacrypt-web
Configure
cp deploy/examples/metacrypt.toml /srv/metacrypt/metacrypt.toml
# Edit to set listen_addr, tls_cert, tls_key, database.path, mcias.server_url
Initialize
./metacrypt init --config /srv/metacrypt/metacrypt.toml
This prompts for a seal password and generates the master encryption key. Store the seal password securely — it cannot be recovered if lost.
Run
./metacrypt server --config /srv/metacrypt/metacrypt.toml
The service starts sealed. Unseal it:
curl -sk -X POST https://localhost:8443/v1/unseal \
-H 'Content-Type: application/json' \
-d '{"password":"<seal-password>"}'
Or use the web UI: navigate to https://<host>:8443/.
Docker
make docker
docker compose -f deploy/docker/docker-compose.yml up -d
See RUNBOOK.md for volume setup instructions.
Further Reading
| Document | Contents |
|---|---|
| ARCHITECTURE.md | Cryptographic design, key hierarchy, engine architecture, API reference, security model |
| RUNBOOK.md | Installation, daily operations, backup/restore, monitoring, troubleshooting |
| PKI-ENGINE-PLAN.md | CA engine implementation plan |
Development
make build # Build all packages
make test # Run tests
make vet # Static analysis
make lint # golangci-lint
make proto # Regenerate protobuf/gRPC stubs
make proto-lint # Lint and check proto breaking changes