With TRUSTED_AUTH_HEADER set, the hub authenticates a request from the
header alone, whichever address it comes from. That is right when every
request passes through the reverse proxy, and not when the hub can also
be reached directly: anyone who can reach it sets the header themselves.
TRUSTED_PROXY_IPS takes a comma-separated list of IPs or CIDR ranges.
When set, the header is only honored on requests whose peer address is
in the list; other requests fall through to the normal authentication.
When unset, nothing changes.
The check uses the connection's RemoteAddr, not a forwarded header, so
the list names the proxy itself. IPv4-mapped IPv6 entries are treated as
IPv4. Entries that do not parse are skipped with a warning on the
console; a list with no valid entry trusts nobody, so a typo narrows the
allowlist instead of widening it.
- move hub's GetEnv function to new utils package to more easily share
across different hub packages
- change System.HasUser to take core.Record instead of user ID string
- add tests
- Validate the user is assigned to system in authenticated routes where
the user passes in system ID. This protects against a somewhat
impractical scenario where an authenticated user cracks a random 15
character alphanumeric ID of a system that doesn't belong to them via
web API.
- Validate that systemd service exists in database before requesting
service details from agent. This protects against authenticated users
getting unit properties of services that aren't explicitly monitored.
- Refactor responses in authenticated routes to prevent enumeration of
other users' random 15 char system IDs.
