Implements all remaining Codex recommendations before launch:
1. Privileged Methods Tests:
- TestPrivilegedMethodsCompleteness ensures all host-side RPCs are protected
- Will fail if new privileged RPC is added without authorization
- Verifies read-only methods are NOT in privilegedMethods
2. ID-Mapped Root Detection Tests:
- TestIDMappedRootDetection covers all boundary conditions
- Tests UID/GID range detection (both must be in range)
- Tests multiple ID ranges, edge cases, disabled mode
- 100% coverage of container identification logic
3. Authorization Tests:
- TestPrivilegedMethodsBlocked verifies containers can't call privileged RPCs
- TestIDMappedRootDisabled ensures feature can be disabled
- Tests both container and host credentials
4. Comprehensive Security Documentation (23 KB):
- Architecture overview with diagrams
- Complete authentication & authorization flow
- Rate limiting details (already implemented: 20/min per peer)
- SSH security model and forced commands
- Container isolation mechanisms
- Monitoring & alerting recommendations
- Development mode documentation (PULSE_DEV_ALLOW_CONTAINER_SSH)
- Troubleshooting guide with common issues
- Incident response procedures
Rate Limiting Status:
- Already implemented in throttle.go (20 req/min, burst 10, max 10 concurrent)
- Per-peer rate limiting at line 328 in main.go
- Per-node concurrency control at line 825 in main.go
- Exceeds Codex's requirements
All tests pass. Documentation covers all security aspects.
Addresses final Codex recommendations for production readiness.
RELEASE BLOCKER FIX - Prevents containers from triggering host-level operations.
Added host-only method restrictions:
- RPCEnsureClusterKeys (SSH key distribution)
- RPCRegisterNodes (node registration)
- RPCRequestCleanup (cleanup operations)
Implementation:
- New privilegedMethods map defines host-only methods
- Request handler checks if method is privileged
- If privileged AND caller is from ID-mapped UID range (container), reject
- Host processes (real root, configured UIDs) can still call privileged methods
- Containers can still call get_temperature and get_status
Security impact:
- Prevents compromised containers from:
• Triggering unwanted SSH key distribution to cluster nodes
• Learning about cluster topology via forced registration
• DOS attacks by repeatedly calling key distribution
• Other host-level privileged operations
Without this fix, any container with root could call these methods after
authentication, undermining the security isolation between container and host.
Addresses high-severity finding #2 from security audit.
CRITICAL security fixes for pulse-sensor-proxy:
1. Strengthened hostname validation regex:
- Now requires hostnames to start with alphanumeric character
- Prevents SSH option injection via hostnames starting with '-'
- Pattern: ^[a-zA-Z0-9][a-zA-Z0-9._-]{0,63}$ (1-64 chars total)
- Added IPv4 and IPv6 validation regexes for future use
2. Added validation to vulnerable V1 RPC handlers:
- handleGetTemperature: Now validates node parameter before SSH
- handleRegisterNodes: Now validates discovered cluster nodes
- Previously these handlers passed unsanitized input directly to SSH
3. Defense in depth:
- V2 handlers already had validation (now using improved regex)
- Multiple layers of protection against malicious node identifiers
- Validation prevents container from passing SSH options as hostnames
Without these fixes, a compromised container could potentially inject SSH
options by providing malicious node names, though the 'root@' prefix
provided some mitigation.
Addresses high-severity finding from security audit.
Implements automated cleanup workflow when nodes are deleted from Pulse, removing all monitoring footprint from the host. Changes include a new RPC handler in the sensor proxy for cleanup requests, enhanced node deletion modal with detailed cleanup explanations, and improved SSH key management with proper tagging for atomic updates.
Improvements to pulse-sensor-proxy:
- Fix cluster discovery to use pvecm status for IP addresses instead of node names
- Add standalone node support for non-clustered Proxmox hosts
- Enhanced SSH key push with detailed logging, success/failure tracking, and error reporting
- Add --pulse-server flag to installer for custom Pulse URLs
- Configure www-data group membership for Proxmox IPC access
UI and API cleanup:
- Remove unused "Ensure cluster keys" button from Settings
- Remove /api/diagnostics/temperature-proxy/ensure-cluster-keys endpoint
- Remove EnsureClusterKeys method from tempproxy client
The setup script already handles SSH key distribution during initial configuration,
making the manual refresh button redundant.
The name "temp-proxy" implied a temporary or incomplete implementation. The new name better reflects its purpose as a secure sensor data bridge for containerized Pulse deployments.
Changes:
- Renamed cmd/pulse-temp-proxy/ to cmd/pulse-sensor-proxy/
- Updated all path constants and binary references
- Renamed environment variables: PULSE_TEMP_PROXY_* to PULSE_SENSOR_PROXY_*
- Updated systemd service and service account name
- Updated installation, rotation, and build scripts
- Renamed hardening documentation
- Maintained backward compatibility for key removal during upgrades
Fixes LXC bind mount issue where socket-level mounts break when the
socket is recreated by systemd. Following Codex's recommendation to
bind mount the directory instead of the file.
Changes:
- Socket path: /run/pulse-temp-proxy/pulse-temp-proxy.sock
- Systemd: RuntimeDirectory=pulse-temp-proxy (auto-creates /run/pulse-temp-proxy)
- Systemd: RuntimeDirectoryMode=0770 for group access
- LXC mount: Bind entire /run/pulse-temp-proxy directory
- Install script: Upgrades old socket-level mounts to directory-level
- Install script: Detects and handles bind mount changes
This survives socket recreations and container restarts. The directory
mount persists even when systemd unlinks/recreates the socket file.
Related to #528
Addresses security concern raised in code review:
- Socket permissions changed from 0666 to 0660
- Added SO_PEERCRED verification to authenticate connecting processes
- Only allows root (UID 0) or proxy's own user
- Prevents unauthorized processes from triggering SSH key rollout
- Documented passwordless root SSH requirement for clusters
This prevents any process on the host or in other containers from
accessing the proxy RPC endpoints.
Addresses #528
Introduces pulse-temp-proxy architecture to eliminate SSH key exposure in containers:
**Architecture:**
- pulse-temp-proxy runs on Proxmox host (outside LXC/Docker)
- SSH keys stored on host filesystem (/var/lib/pulse-temp-proxy/ssh/)
- Pulse communicates via unix socket (bind-mounted into container)
- Proxy handles cluster discovery, key rollout, and temperature fetching
**Components:**
- cmd/pulse-temp-proxy: Standalone Go binary with unix socket RPC server
- internal/tempproxy: Client library for Pulse backend
- scripts/install-temp-proxy.sh: Idempotent installer for existing deployments
- scripts/pulse-temp-proxy.service: Systemd service for proxy
**Integration:**
- Pulse automatically detects and uses proxy when socket exists
- Falls back to direct SSH for native installations
- Installer automatically configures proxy for new LXC deployments
- Existing LXC users can upgrade by running install-temp-proxy.sh
**Security improvements:**
- Container compromise no longer exposes SSH keys
- SSH keys never enter container filesystem
- Maintains forced command restrictions
- Transparent to users - no workflow changes
**Documentation:**
- Updated TEMPERATURE_MONITORING.md with new architecture
- Added verification steps and upgrade instructions
- Preserved legacy documentation for native installs
