Implemented a comprehensive secure authentication mechanism for inter-node
cluster communication with the following features:
1. Global Cluster Secret (GCS)
- Auto-generated cryptographically secure random secret (256-bit)
- Configurable via YAML config file
- Shared across all cluster nodes for authentication
2. Cluster Authentication Middleware
- Validates X-Cluster-Secret and X-Node-ID headers
- Applied to all cluster endpoints (/members/*, /merkle_tree/*, /kv_range)
- Comprehensive logging of authentication attempts
3. Authenticated HTTP Client
- Custom HTTP client with cluster auth headers
- TLS support with configurable certificate verification
- Protocol-aware (http/https based on TLS settings)
4. Secure Bootstrap Endpoint
- New /auth/cluster-bootstrap endpoint
- Protected by JWT authentication with admin scope
- Allows new nodes to securely obtain cluster secret
5. Updated Cluster Communication
- All gossip protocol requests include auth headers
- All Merkle tree sync requests include auth headers
- All data replication requests include auth headers
6. Configuration
- cluster_secret: Shared secret (auto-generated if not provided)
- cluster_tls_enabled: Enable TLS for inter-node communication
- cluster_tls_cert_file: Path to TLS certificate
- cluster_tls_key_file: Path to TLS private key
- cluster_tls_skip_verify: Skip TLS verification (testing only)
This implementation addresses the security vulnerability of unprotected
cluster endpoints and provides a flexible, secure approach to protecting
internal cluster communication while allowing for automated node bootstrapping.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
- Create cluster/merkle.go with Merkle tree operations
- Create cluster/gossip.go with gossip protocol implementation
- Create cluster/sync.go with data synchronization logic
- Create cluster/bootstrap.go with cluster joining functionality
Major clustering functionality now properly separated:
* MerkleService: Tree building, hashing, filtering
* GossipService: Member discovery, health checking, list merging
* SyncService: Merkle-based synchronization between nodes
* BootstrapService: Seed node joining and initial sync
Build tested and verified working. Ready for main.go integration.
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
