hyperhive/hive-priv
Repository files (latest commit first)
Filename Latest commit message Latest commit date
atlas e407fa93df feat(#2754): hive-wide CPUWeight= / IOWeight= for agent containers
`CPUQuota=`/`MemoryMax=` are hard caps: they throttle an agent even when
the host is idle, so they are the wrong tool for "be polite under
contention". The cgroup v2 relative shares are, and neither was wired.

Adds `services.hyperhive.{agentCpuWeight,agentIoWeight}` (1..=10000,
default 80) threaded through the existing drop-in path: HiveEnv ->
write_dropins -> WriteResourceLimits -> hyperhive-limits.conf, next to
the caps already there. Hive-wide only, as the operator scoped it on the
issue: no per-agent override, no resource-limits.json field, no
dashboard form.

The default of 80 is below the kernel's 100, so agent containers yield
to everything *not* on this drop-in path -- host services and the infra
containers (hive-ci, hive-forge, hive-gateway, hive-matrix). It does not
rank agents against each other; they all carry the same weight.

`WriteResourceLimits` gains two `#[serde(default)]` fields, and the
writer treats weight 0 as "not configured" and omits the line, so an
older hive-c0re talking to a newer hive-priv still produces the exact
pre-weights drop-in. The body is extracted into `limits_dropin_body` so
that is covered by a test rather than asserted by eye.
2026-07-27 10:25:30 +02:00
..
src feat(#2754): hive-wide CPUWeight= / IOWeight= for agent containers 2026-07-27 10:25:30 +02:00
Cargo.toml docs(#2627): add READMEs for the remaining infra crates 2026-07-23 13:16:29 +02:00
README.md docs(#2627): add READMEs for the remaining infra crates 2026-07-23 13:16:29 +02:00

hive-priv

The minimal root privileged-helper for hive-c0re. It runs as root and exposes a narrow unix socket at /run/hive/priv.sock that accepts PrivRequest JSON lines and performs only the handful of operations that genuinely require root — bind-mount edits, nsenter into a container, btrfs subvolume ops. All coordination logic (broker, HTTP, scheduling) stays in the unprivileged hive-c0re process, which delegates here.

Why it exists

Privsep. hive-c0re runs as the unprivileged hive-core user so a bug or a prompt-injection in the large daemon can't directly wield root. The few root operations it needs are funnelled through this small, auditable helper instead. See docs/boundary.md and docs/security.md for the privilege boundary.

Security model

  • Strict allowlist. Every request is validated against a container-name allowlist before any filesystem or process operation — only names matching the hive convention (h-*, the manager container, known sibling service containers) are accepted.
  • No pass-through. Every PrivRequest variant maps to a single known operation; there is no arbitrary-command escape hatch.
  • Socket-activated, always. systemd binds /run/hive/priv.sock (SocketGroup=hive-core, 0660) and passes the listener as fd 3 (LISTEN_FDS); the helper requires this and has no self-bind fallback, so dev and prod take the identical path and the group grant always holds.

The wire contract (PrivRequest / response types) lives in the separate hive-priv-sock crate so this root binary depends on just the protocol shapes, not the whole daemon-shared crate.