The production gateway does not face the internet: nginx-proxy-manager owns
80/443 on the host and proxies to it. So $remote_addr inside the gateway is that
proxy, and overwriting X-Forwarded-For with it discarded the customer address
the proxy had already recorded. Every request would have been attributed to one
internal address, which is exactly the fault 2.1 set out to fix, reintroduced in
production only.
Use real_ip to take the customer address from the proxy's header, trusting only
private networks. A request that reaches the published port directly from the
internet is not trusted, so its header is ignored and $remote_addr stays the
real peer: the anti-spoofing property is kept.
Also downgrade 2.9. TLS is not missing, it is terminated by that proxy. The gap
is that the repository never says so, which would break every session cookie if
the stack moved to a host without one.
Validated with nginx -t against the rendered production configuration.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
uvicorn does not trust forwarded headers from a peer outside
forwarded_allow_ips, so request.client.host was the web gateway for every
request. The auth-source bucket therefore counted all customers together:
60 failed logins from one attacker locked out everyone. Security events
recorded the gateway address, which made the audit trail useless for
attribution.
The gateway now overwrites X-Forwarded-For with the peer address it observed
instead of appending to whatever the client sent, so the header carries one
value the client cannot choose, and client_ip() resolves it with a fallback to
the connection peer.
The guest-session limiter was keyed on the environment name, making it one
global bucket of 120 per 15 minutes: roughly eight new visitors a minute for
the whole site before legitimate traffic started receiving 429. It is now per
source, and the ceiling is deliberately generous because offices and mobile
carriers put many real customers behind a single address.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
