hyperhive/swarm-controller
Repository files (latest commit first)
Filename Latest commit message Latest commit date
atlas ffd5018b18 swarm: mint a per-agent queue credential beside the agent's store identity
Every agent on a hive authenticates to the swarm queue with the same
hive-scoped secret today, so at the auth callout one agent is
indistinguishable from its co-hived neighbours and no subject can be
scoped to one of them.

Mint a secret per agent instead, at swarm level, into
secret/swarm/agents/<agent>/queue -- inside the stanza every agent's ACL
document already grants, so no policy changes and no existing agent's
document is rewritten. It is written by the same node that already mints
the agent's certificate, and read back under the agent's own token
before that node reports success.

The secret is not derived from the agent's mTLS identity: the two
credentials answer different questions and coupling their lifetimes
would mean renewing either implied renewing the other. Nothing here
rotates a queue secret -- a re-run keeps the existing value and only
corrects the principal it names, because this function is re-run
deliberately against agents that are already connected. Revoking one
means deleting the path.

Nothing reads the new credential yet; this is the minting half.
2026-09-21 20:38:55 +02:00
..
src swarm: mint a per-agent queue credential beside the agent's store identity 2026-09-21 20:38:55 +02:00
Cargo.toml swarm: mint a per-agent queue credential beside the agent's store identity 2026-09-21 20:38:55 +02:00
README.md check-issue-refs: catch full forge issue URLs too, drop internal links from docs entirely 2026-09-09 21:15:28 +02:00

swarm-controller

The swarm-level daemon. Where hive-c0re owns the agents on one host, this owns what is true across hives — so a swarm runs one of them and most hives leave it off.

Opt-in per host via services.hyperhive.deploy.swarm-controller.enable, which is deliberately not derived from services.hyperhive.enable: turning it on is a statement about swarm topology, not about whether hyperhive is installed.

What it does today

Serves one /health endpoint and holds no state.

That is the whole intent of the first slice. The point is to make the unit real — service user, runtime and state directories, socket, nginx reachability — so the swarm-level surfaces that follow have somewhere to land. Inventing those surfaces before they are agreed would bake in a shape nobody chose. See the hyperhive.swarm consolidation epic.

Why a unix socket, not a port

The hive-gateway's nginx is the only intended client and reaches the socket through a bind-mount. A listener that is never bound to an address cannot be reached from off-host by mistake.

The socket path is services.hyperhive.deploy.swarm-controller.socketPath, default /run/swarm-controller/controller.sock, exported to the process as SWARM_CONTROLLER_SOCKET.

⚠️ The socket's directory is its access control

The socket is 0666. It has to be: nginx runs as a different user and connect(2) needs write. This matches how hive-c0re publishes the per-agent sockets, and rests on the same argument — "the bind source dir is per-agent on host so blast radius is unchanged."

What keeps that safe is that the directory holds one socket. So:

Never point socketPath at a directory that carries anything else. /run/hyperhive above all — it holds host.sock, the host admin socket. Pointing nginx at that directory to reach this socket would put the admin socket within its reach too.

nginx is a host service, so nothing narrows what it can reach except the directory itself — that is the whole of the access control. A unit test pins the default path so a tidying edit fails instead of reviewing cleanly.

RuntimeDirectoryPreserve=yes and the daemon's stale-socket unlink on start are a pair: preserving the directory without the unlink means bind fails with EADDRINUSE after a restart.

Packaging

Built by the workspace derivation and extracted as its own package (nix build .#swarm-controller). Deliberately not in nix/packages' daemonBins — that list is the core stack and drives the bundle services.hyperhive.c0re.package points at, so folding this in would put a swarm-scoped service into every hive's closure.