mirror of
https://github.com/hoernschen/dendrite.git
synced 2024-12-27 07:28:27 +00:00
106 lines
3.5 KiB
Go
106 lines
3.5 KiB
Go
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package auth
|
|
|
|
import (
|
|
"context"
|
|
|
|
"github.com/matrix-org/dendrite/roomserver/api"
|
|
"github.com/matrix-org/gomatrixserverlib"
|
|
"github.com/matrix-org/gomatrixserverlib/spec"
|
|
)
|
|
|
|
// TODO: This logic should live in gomatrixserverlib
|
|
|
|
// IsServerAllowed returns true if the server is allowed to see events in the room
|
|
// at this particular state. This function implements https://matrix.org/docs/spec/client_server/r0.6.0#id87
|
|
func IsServerAllowed(
|
|
ctx context.Context, querier api.QuerySenderIDAPI,
|
|
serverName spec.ServerName,
|
|
serverCurrentlyInRoom bool,
|
|
authEvents []gomatrixserverlib.PDU,
|
|
) bool {
|
|
// In practice should not happen, but avoids unneeded CPU cycles
|
|
if serverName == "" || len(authEvents) == 0 {
|
|
return false
|
|
}
|
|
historyVisibility := HistoryVisibilityForRoom(authEvents)
|
|
|
|
// 1. If the history_visibility was set to world_readable, allow.
|
|
if historyVisibility == gomatrixserverlib.HistoryVisibilityWorldReadable {
|
|
return true
|
|
}
|
|
// 2. If the user's membership was join, allow.
|
|
joinedUserExists := IsAnyUserOnServerWithMembership(ctx, querier, serverName, authEvents, spec.Join)
|
|
if joinedUserExists {
|
|
return true
|
|
}
|
|
// 3. If history_visibility was set to shared, and the user joined the room at any point after the event was sent, allow.
|
|
if historyVisibility == gomatrixserverlib.HistoryVisibilityShared && serverCurrentlyInRoom {
|
|
return true
|
|
}
|
|
// 4. If the user's membership was invite, and the history_visibility was set to invited, allow.
|
|
invitedUserExists := IsAnyUserOnServerWithMembership(ctx, querier, serverName, authEvents, spec.Invite)
|
|
if invitedUserExists && historyVisibility == gomatrixserverlib.HistoryVisibilityInvited {
|
|
return true
|
|
}
|
|
|
|
// 5. Otherwise, deny.
|
|
return false
|
|
}
|
|
|
|
func HistoryVisibilityForRoom(authEvents []gomatrixserverlib.PDU) gomatrixserverlib.HistoryVisibility {
|
|
// https://matrix.org/docs/spec/client_server/r0.6.0#id87
|
|
// By default if no history_visibility is set, or if the value is not understood, the visibility is assumed to be shared.
|
|
visibility := gomatrixserverlib.HistoryVisibilityShared
|
|
for _, ev := range authEvents {
|
|
if ev.Type() != spec.MRoomHistoryVisibility {
|
|
continue
|
|
}
|
|
if vis, err := ev.HistoryVisibility(); err == nil {
|
|
visibility = vis
|
|
}
|
|
}
|
|
return visibility
|
|
}
|
|
|
|
func IsAnyUserOnServerWithMembership(ctx context.Context, querier api.QuerySenderIDAPI, serverName spec.ServerName, authEvents []gomatrixserverlib.PDU, wantMembership string) bool {
|
|
for _, ev := range authEvents {
|
|
if ev.Type() != spec.MRoomMember {
|
|
continue
|
|
}
|
|
membership, err := ev.Membership()
|
|
if err != nil || membership != wantMembership {
|
|
continue
|
|
}
|
|
|
|
stateKey := ev.StateKey()
|
|
if stateKey == nil {
|
|
continue
|
|
}
|
|
|
|
validRoomID, err := spec.NewRoomID(ev.RoomID())
|
|
if err != nil {
|
|
continue
|
|
}
|
|
userID, err := querier.QueryUserIDForSender(ctx, *validRoomID, spec.SenderID(*stateKey))
|
|
if err != nil {
|
|
continue
|
|
}
|
|
|
|
if userID.Domain() == serverName {
|
|
return true
|
|
}
|
|
}
|
|
return false
|
|
}
|