Server half of the active-sessions surface. Web UI follows.
The operator wants this specifically to notice a compromised account, which
sets the bar: the addresses have to be trustworthy, or the feature is worse
than absent because it looks like evidence.
Migration 0052 adds created_ip + last_ip. Two columns, not one, and the pair
is the signal: a session issued at home and now being used from elsewhere is
the shape of a stolen token, and neither column alone can show that. Typed
text, matching the user_agent column beside it — these are displayed, never
queried by subnet, and inet round-trips through pgx as a netip.Prefix that
renders "1.2.3.4/32".
The rest of the schema was already waiting. Migration 0004 anticipated this
exactly: "last_seen_at enables an 'active sessions' UI later (not wired in
this plan) without schema churn." last_seen_at is live data — the auth
middleware already touches it per request — so last_ip rides that same
UPDATE for free.
Getting the address right is the substance here. Nothing extracted a client
IP anywhere before, and both obvious approaches are wrong:
- RemoteAddr alone shows the reverse proxy on every session, which is the
normal self-hosted deployment. Noise shaped like data.
- Trusting X-Forwarded-For lets any client choose what its victim sees. A
security surface an attacker can write to is worse than none.
So auth.ClientIP trusts the header only when the request actually arrived
from a proxy range. Public RemoteAddr means a direct connection, so XFF is
attacker-controlled and ignored outright. Private RemoteAddr means we walk
XFF right-to-left — proxies append, so the right end is what our own
infrastructure wrote — and take the first non-proxy address. A forged XFF
only prepends to the left end, which that walk never reaches. Unit-tested,
including both spoofing shapes.
Fails closed on a public-addressed proxy (separate host, CDN): we report the
proxy rather than trusting a forgeable header. Documented at the function.
Endpoints, all scoped by user_id per rule #47:
GET /api/me/sessions → list, flagging the current row
DELETE /api/me/sessions/{id} → 204, or 404 if not yours
POST /api/me/sessions/logout-others → {"revoked": n}
Keyed on session id alone, any household member could revoke another's
session by guessing a uuid, so the delete carries user_id in its WHERE and
:execrows distinguishes "not yours" (404) from a false 204. There's a test
that asserts the row actually survives, not merely that we returned 404.
The middleware now also puts the session id in context. logout-others is
defined by exclusion, and without knowing which session is ours the
safe-looking action deletes everything including the caller's — so it
refuses rather than guesses when the id is absent, and that refusal is
tested for non-deletion too.
audit_log.action is plain text with no CHECK, so the two new actions need no
migration (rule #36 checked, not assumed).
Codegen is real sqlc 1.31.1 via the container in `make generate` — docker is
present on this workstation even though Go and sqlc aren't — rather than the
hand-written .sql.go shortcut used in milestone #268.
Replaces the old X-API-Token-based RequireAdmin in middleware.go with a
context-aware RequireAdmin() that runs after RequireUser, checks
user.IsAdmin, and returns 403 {"error":"not_authorized"} for non-admins
or 500 {"error":"internal_error"} if RequireUser was bypassed. Updates
server.go to mount RequireUser then RequireAdmin on the /api/admin group.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
bvandeusen
