hyperhive/hive-priv
Repository files (latest commit first)
Filename Latest commit message Latest commit date
atlas c5cd8f2ac4 docs: state the unlink mechanism precisely (write bit, not sticky bit)
Both the gateway doc and the tmpfiles comment said "a directory without
the sticky bit lets any user unlink files in it". True of the old 0777,
but it names the wrong lever: write permission on a directory is what
confers the right to unlink its entries, and the sticky bit is only a
restraint on that -- it was never set here, so it is not what 0751
changes. Dropping o=w removes the permission outright.

The fix is unchanged; this is so a future reader doesn't go looking for
a sticky bit that was never there. Caught in review by argus.
2026-08-04 01:00:48 +02:00
..
src docs: state the unlink mechanism precisely (write bit, not sticky bit) 2026-08-04 01:00:48 +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.