lattice-node-agent

Outbound node daemon for Lattice.

The agent has no inbound listener. It authenticates with a per-node token, reports metrics and slow-changing HostFacts inventory telemetry, polls for queued tasks, executes bounded tasks only when explicitly enabled, and posts results back to the server. It can also report proxy-core traffic counters from a bounded local JSON snapshot file for the server-owned usage rollup. Node tokens are sent in the Authorization: Bearer header, not in JSON bodies. For rollback-protected firewall apply tasks, the binary also supports --selfcheck-controlplane, a one-shot unauthenticated /api/health reachability check used after nft commit; this mode does not require or send the node token.

HostFacts are best-effort advisory facts (OS, arch, CPU cores/model, memory/swap, platform, kernel, hostname, boot time, virtualization hint). They are collected with stdlib and local platform files such as /proc and /etc/os-release; missing fields are left empty and never block the agent.

Run

go run ./cmd/lattice-agent \
  -server http://127.0.0.1:8088 \
  -node-id demo-node \
  -token '<enrollment-token>' \
  -allow-exec=false

-allow-exec=false is the safe default. Use -allow-exec=true only on nodes where remote script execution is acceptable.

The node token is sent in the Authorization: Bearer header on every request. The loopback http://127.0.0.1:8088 URL above is safe because the token never leaves the host. For a remote server the agent refuses to start on a cleartext http:// URL (it would leak the token) — use https:// instead. The -allow-insecure-http flag exists only as a deliberate escape hatch and is off by default.

Firewall apply selfcheck:

lattice-agent --selfcheck-controlplane -server https://203.0.113.99

The selfcheck exits 0 only when GET /api/health returns HTTP 200. It reuses the same transport safety guard as normal startup, so remote cleartext http:// is refused unless deliberately allowed.

Firewall apply domain-set update:

lattice-agent --update-nft-domain-set \
  -host lattice.example.com \
  -family inet \
  -table lattice_policy \
  -set lattice_control4 \
  -set6 lattice_control6

This mode resolves the hostname with Go's resolver, splits answers into IPv4 and IPv6 sets, sorts/deduplicates each family, then updates the existing nft named sets using direct nft argv calls. -set may be used alone for the legacy IPv4-only path; -set + -set6 updates both control-plane sets and requires at least one A or AAAA answer. It does not require or send the node token. It is intended for server-rendered, rollback-protected apply scripts; empty resolution or invalid nft identifiers exit non-zero so the task can roll back.

Proxy usage reporting bridge:

lattice-agent \
  -server https://lattice.example.com \
  -node-id gmami-jp1 \
  -token '<node-token>' \
  -proxy-usage-file /run/lattice/proxy-usage.json

The file is read once per agent loop and posted to /api/agent/proxy-usage. The agent overrides any node_id in the file with its configured node id, defaults at when omitted, rejects empty user ids, rejects negative counters, and refuses files over 1 MiB. The server performs monotonic diffing, per-profile user eligibility filtering, quota status updates, and audit.

Minimal file shape:

{
  "core_uptime_sec": 12345,
  "user_bytes": {
    "alice": 1048576,
    "bob": 2097152
  }
}

This is an interim stable contract for sidecar collectors and future direct sing-box/xray collectors; it is not a general log or metrics ingestion channel.

Execution Limits

• Interpreter allowlist: sh, bash, python3, node.
• Default timeout: 30 seconds.
• Maximum timeout: 10 minutes.
• Output cap: up to 256 KiB.
• Server-side task creation enforces the same interpreter, timeout, output, and script-size limits before a task can be leased.
• Server-side result ingestion also rejects stdout, stderr, or error text that exceeds the task's output cap.
• Temporary working directory and minimal environment.
• Leased tasks carry a server-issued lease_id; the agent returns it with the result and exposes it to the task as LATTICE_TASK_LEASE_ID for traceability.
• Leased task payloads contain only execution fields; control-plane actor/token metadata is not sent to agents.

Development

go test ./...
go build ./cmd/lattice-agent