to send one message to four accounts an hour ago i found the sidecar's
ephemeral port and POSTed to it directly, once per user, with no
authentication of any kind. that worked, which was the problem: the same
door was open to anything else on the machine, including a commander with
a shell.
two changes.
POST /api/notify/broadcast, owner only via `ownerOnly` on the permission —
the supported way to say one thing to everyone. teams will narrow it later;
today the choice is everyone or one person.
and the sidecar now requires a secret on everything under /_officer/. it
is generated per boot, held in memory, announced to the platform over the
registration socket beside the port, and never written to disk.
X-Officer-User could not carry this on its own, and my first attempt got
that wrong: it says WHO is asking, and a caller on loopback can write it
itself. only the secret says the PLATFORM is asking. so the check covers
the whole /_officer/ surface rather than just the send route — /_officer/
devices takes the same header to decide whose phones are listed and
deleted.
what it bounds, honestly: a MEMBER's commander runs as its own Linux user
and cannot read this process, so for every account but the owner's this is
kernel-enforced. the owner's own commander runs as the owner, same as the
platform, and is not bounded by this and cannot be — the same reason
`execution` permissions are never grantable. the owner's decision, and
this is a real improvement rather than a boundary.
`bun run notify:test` posts to that port and will now be refused. it is a
developer CLI on a box where the platform is running; left to fail loudly
rather than given a way in.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Officer-Session: 656f5c85-e49a-4f1f-b9f3-042a04b4d043
pastilhasandClaude Opus 5
cb2dcfa4cc