Files
Warp/server/internal/federation/requestauth.go
T
tajniak81andClaude Opus 5.5 6aaf554336
CI / Test (ubuntu-latest) (push) Canceled after 0s
CI / Test (windows-latest) (push) Canceled after 0s
CI / Storage tests on PostgreSQL (push) Canceled after 0s
CI / Complement (federation off) (push) Canceled after 0s
CI / golangci-lint (push) Canceled after 0s
CI / Smoke test the binary (push) Canceled after 0s
Phase 5: federation
Implements PLAN.md Phase 5: the Server-Server API. Warp joins rooms on
other servers and lets their users join its rooms, invites across servers
with the invitee's server countersigning, rejects remote invites (locally
if the inviter is unreachable), and exchanges events, typing, receipts and
to-device messages with other homeservers — all behind the runtime switch,
which now starts and stops real outbound traffic.

The protocol lives in internal/federation with no knowledge of rooms:
X-Matrix signing (fuzzed parser), the spec's discovery algorithm keeping
the dial address and the TLS name apart, a signed client that refuses
every request while the switch is off or the policy denies the
destination, and a key ring that caches other servers' keys for at most a
week, with optional notaries.

The roomserver takes events from elsewhere through the spec's intake:
signatures and hashes (a hash mismatch keeps the redacted form), the rules
against the event's own auth events, against the state before it — with
/get_missing_events for small gaps and /state_ids for wide ones — and
against the current state, where a failure is a soft failure. Events held
without their state are outliers: a column on roomserver_events, because
the current state of a room joined over federation is almost all
outliers, and excluded from every timeline query. Forks are resolved at
the room's head. Membership across servers is make_join/send_join,
make_leave/send_leave and countersigned invites, in both directions;
m.room.server_acl is enforced on everything another server sends.
History before a remote join is backfilled when /messages pages past it,
stored at negative stream positions.

internal/federationapi is the running component: the inbound endpoints,
and an outbound queue that persists what it owes each destination, sends
it in transactions of 50 PDUs and 100 EDUs, backs off from ten seconds to
six hours, survives restarts, and drops events persisted while federation
is off rather than delivering a backlog in one burst. Its Module is what
the switch starts and stops.

Also: a TLS listener for port 8448, trusted key servers, key validity and
an outbound CA bundle in the config; per-destination health and backoff
reset in the admin API; remote profiles, aliases and directories in the
Client-Server API; a Complement federation profile. See
docs/federation.md, including its known gaps (no partial-state joins, no
key rotation).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-16 17:14:20 +02:00

69 lines
2.1 KiB
Go

package federation
import (
"context"
"fmt"
"net/http"
)
// AuthenticateRequest checks the X-Matrix signature on an inbound request
// and returns the server it came from.
//
// content is the request body, already read; the signature covers it, so
// the caller reads it once and hands the same bytes here and to its own
// decoder. A request may carry one Authorization header per key it is
// signed with, and any one that verifies is enough.
func (k *KeyRing) AuthenticateRequest(ctx context.Context, r *http.Request, content []byte) (string, error) {
headers := r.Header.Values("Authorization")
if len(headers) == 0 {
return "", fmt.Errorf("%w: no Authorization header", ErrBadAuthorization)
}
var (
origin string
lastErr error
)
for _, h := range headers {
x, err := ParseXMatrix(h)
if err != nil {
lastErr = err
continue
}
if origin != "" && x.Origin != origin {
// Two headers naming two origins is one request claiming to
// be from two servers; neither claim is worth checking.
return "", fmt.Errorf("%w: headers name both %s and %s", ErrBadAuthorization, origin, x.Origin)
}
origin = x.Origin
if x.Destination != "" && x.Destination != k.serverName {
lastErr = fmt.Errorf("%w: addressed to %s, not to this server", ErrBadAuthorization, x.Destination)
continue
}
if x.Origin == k.serverName {
lastErr = fmt.Errorf("%w: a request claiming to be from this server", ErrBadAuthorization)
continue
}
// The destination in the signed object is whatever the sender put
// in the header, or this server's name when it put nothing: a
// sender old enough to leave it out signed with it absent from
// the header, not from the object.
destination := x.Destination
if destination == "" {
destination = k.serverName
}
signed, err := requestSignedJSON(x, destination, r.Method, r.RequestURI, content)
if err != nil {
lastErr = err
continue
}
if err := k.VerifyJSON(ctx, x.Origin, signed); err != nil {
lastErr = fmt.Errorf("%w: %v", ErrBadAuthorization, err)
continue
}
return x.Origin, nil
}
return "", lastErr
}