Engines listen on every address their node has, with no key. Checked on the
live cluster: from a neighbouring node, a request straight to an engine's
port was answered — past the gateway's authentication, quotas and
accounting, by anyone who could reach the node.
Each replica's engine is now started with a key and refuses requests without
it. The key is derived from the replica id with an HMAC over a secret kept
in the store, rather than stored per replica: the router has to send the
right key to replicas this process never started — adopted after a restart,
or placed by the other control plane — and a function of a shared secret
gives that without a table to keep in step. A key taken from one node opens
that replica only. The secret is made on first use and copied with the rest
of the store when moving to PostgreSQL; a new one would lock the router out
of every running engine at the moment of the move.
The key reaches llama.cpp and vLLM through their environment
(LLAMA_API_KEY, VLLM_API_KEY) rather than their command line, which every
user on the node can read; SGLang only takes it as an argument. The agent's
readiness check, the router's proxy and its metrics scrape send it, the
client's own Authorization still never reaches the engine, and `ctl bench`
fetches the key of the replica it is pointed at from the admin API.
Engines started before this keep running without a key until their replica
is next started. With no store there is nowhere to keep the secret, and
engines start without one, with a warning.
Also formats two files that went in unformatted.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Checked on the live cluster: from any node, the mirror's management API on
:8082 answered — list, fetch, delete — with no credentials. Unset
--api-allow meant anyone. It now means this machine only; the control plane
is let in with --api-allow, which `server init` already wrote for the
mirrors it sets up, or by mutual TLS.
A fetch went to whatever URL it was given, and the file server on :8081
then handed the result to anyone: "fetch http://169.254.169.254/..." read a
cloud's instance metadata through the mirror, and a URL on the LAN read
whatever answered there. Downloads started through the API now go to http
and https only, and are refused at dial time — after resolution, on every
redirect — when the address is loopback, private, link-local, CGNAT or
multicast. --allow-private-sources lets them through for a mirror that
really does copy from a server on its own network. `llmgw mirror add`, run
by someone on the mirror itself, is unchanged.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>