chore(communities)_: reject outdated community descriptions

Prevent the inclusion of CommunityDescription with an outdated clock in
MessengerResponse to avoid false-positives in tests and reduce redundant
data exchange between status-go and clients.

protocol/communities/community.go

@@ -1130,11 +1130,9 @@ func (o *Community) UpdateCommunityDescription(description *protobuf.CommunityDe
 		return nil, err
 	}
 
-	response := o.emptyCommunityChanges()
-
 	// Enables processing of identical clocks. Identical descriptions may be reprocessed upon subsequent receipt of the previously missing encryption key.
 	if description.Clock < o.config.CommunityDescription.Clock {
-		return response, nil
+		return nil, ErrInvalidCommunityDescriptionClockOutdated
 	}
 
 	originCommunity := o.CreateDeepCopy()
@@ -1146,6 +1144,8 @@ func (o *Community) UpdateCommunityDescription(description *protobuf.CommunityDe
 		o.setControlNode(newControlNode)
 	}
 
+	response := o.emptyCommunityChanges()
+
 	// We only calculate changes if we joined/spectated the community or we requested access, otherwise not interested
 	if o.config.Joined || o.config.Spectated || o.config.RequestedToJoinAt > 0 {
 		response = EvaluateCommunityChanges(originCommunity, o)

protocol/communities/community_test.go

@@ -567,8 +567,8 @@ func (s *CommunitySuite) TestHandleCommunityDescription() {
 			name:        "updated version but lower clock",
 			description: s.oldCommunityDescription,
 			signer:      signer,
-			changes:     buildChanges,
-			err:         nil,
+			changes:     func(c *Community) *CommunityChanges { return nil },
+			err:         ErrInvalidCommunityDescriptionClockOutdated,
 		},
 		{
 			name:        "removed member from org",

protocol/communities/errors.go

@@ -12,6 +12,7 @@ var ErrChatAlreadyExists = errors.New("chat already exists")
 var ErrCategoryAlreadyExists = errors.New("category already exists")
 var ErrCantRequestAccess = errors.New("can't request access")
 var ErrInvalidCommunityDescription = errors.New("invalid community description")
+var ErrInvalidCommunityDescriptionClockOutdated = errors.New("invalid community description outdated clock")
 var ErrInvalidCommunityDescriptionNoOrgPermissions = errors.New("invalid community description no org permissions")
 var ErrInvalidCommunityDescriptionNoChatPermissions = errors.New("invalid community description no chat permissions")
 var ErrInvalidCommunityDescriptionUnknownChatAccess = errors.New("invalid community description unknown chat access")

protocol/communities_messenger_test.go

@@ -4554,3 +4554,66 @@ func (s *MessengerCommunitiesSuite) TestAliceDidNotProcessOutdatedCommunityReque
 	err = s.alice.HandleCommunityRequestToJoinResponse(state, requestToJoinResponse, nil)
 	s.Require().NoError(err)
 }
+
+func (s *MessengerCommunitiesSuite) TestIgnoreOutdatedCommunityDescription() {
+	community, _ := s.createCommunity()
+	wrappedDescription1, err := community.ToProtocolMessageBytes()
+	s.Require().NoError(err)
+	signer, description1, err := communities.UnwrapCommunityDescriptionMessage(wrappedDescription1)
+	s.Require().NoError(err)
+
+	_, err = community.AddMember(&s.alice.identity.PublicKey, []protobuf.CommunityMember_Roles{})
+	s.Require().NoError(err)
+	wrappedDescription2, err := community.ToProtocolMessageBytes()
+	s.Require().NoError(err)
+	_, description2, err := communities.UnwrapCommunityDescriptionMessage(wrappedDescription2)
+	s.Require().NoError(err)
+
+	_, err = community.AddMember(&s.bob.identity.PublicKey, []protobuf.CommunityMember_Roles{})
+	s.Require().NoError(err)
+	wrappedDescription3, err := community.ToProtocolMessageBytes()
+	s.Require().NoError(err)
+	_, description3, err := communities.UnwrapCommunityDescriptionMessage(wrappedDescription3)
+	s.Require().NoError(err)
+
+	s.Require().Less(description1.Clock, description2.Clock)
+	s.Require().Less(description2.Clock, description3.Clock)
+
+	// Handle first community description
+	{
+		messageState := s.bob.buildMessageState()
+		err = s.bob.handleCommunityDescription(messageState, signer, description1, wrappedDescription1, nil, nil)
+		s.Require().NoError(err)
+		s.Require().Len(messageState.Response.Communities(), 1)
+		s.Require().Equal(description1.Clock, messageState.Response.Communities()[0].Clock())
+	}
+
+	// Handle third community description
+	{
+		messageState := s.bob.buildMessageState()
+		err = s.bob.handleCommunityDescription(messageState, signer, description3, wrappedDescription3, nil, nil)
+		s.Require().NoError(err)
+		s.Require().Len(messageState.Response.Communities(), 1)
+		s.Require().Equal(description3.Clock, messageState.Response.Communities()[0].Clock())
+
+		communityFromDB, err := s.bob.communitiesManager.GetByID(community.ID())
+		s.Require().NoError(err)
+		s.Require().Equal(description3.Clock, communityFromDB.Clock())
+		s.Require().Len(communityFromDB.Members(), 3)
+	}
+
+	// Handle second (out of order) community description
+	// It should be ignored
+	{
+		messageState := s.bob.buildMessageState()
+		err = s.bob.handleCommunityDescription(messageState, signer, description2, wrappedDescription2, nil, nil)
+		s.Require().Len(messageState.Response.Communities(), 0)
+		s.Require().Len(messageState.Response.CommunityChanges, 0)
+		s.Require().ErrorIs(err, communities.ErrInvalidCommunityDescriptionClockOutdated)
+
+		communityFromDB, err := s.bob.communitiesManager.GetByID(community.ID())
+		s.Require().NoError(err)
+		s.Require().Equal(description3.Clock, communityFromDB.Clock())
+		s.Require().Len(communityFromDB.Members(), 3)
+	}
+}

protocol/messenger_communities.go

@@ -3693,7 +3693,8 @@ func (m *Messenger) handleSyncInstallationCommunity(messageState *ReceivedMessag
 
 	// TODO: handle shard
 	err = m.handleCommunityDescription(messageState, signer, &cd, syncCommunity.Description, signer, nil)
-	if err != nil {
+	// Even if the Description is outdated we should proceed in order to sync settings and joined state
+	if err != nil && err != communities.ErrInvalidCommunityDescriptionClockOutdated {
 		logger.Debug("m.handleCommunityDescription error", zap.Error(err))
 		return err
 	}