Do not show stories for inactive groups.

app/src/main/java/org/thoughtcrime/securesms/jobs/PushGroupSendJob.java

@@ -185,6 +185,10 @@ public final class PushGroupSendJob extends PushSendJob {
       throw new MmsException("No GV1 messages can be sent anymore!");
     }
 
+    if ((message.getStoryType().isStory() || message.getParentStoryId() != null) && !groupRecipient.isActiveGroup()) {
+      throw new MmsException("Not a member of the group!");
+    }
+
     try {
       log(TAG, String.valueOf(message.getSentTimeMillis()), "Sending message: " + messageId + ", Recipient: " + message.getRecipient().getId() + ", Thread: " + threadId + ", Attachments: " + buildAttachmentString(message.getAttachments()));
 

app/src/main/java/org/thoughtcrime/securesms/messages/MessageContentProcessor.java

@@ -1462,7 +1462,17 @@ public final class MessageContentProcessor {
   private void handleStoryMessage(@NonNull SignalServiceContent content, @NonNull SignalServiceStoryMessage message, @NonNull Recipient senderRecipient, @NonNull Recipient threadRecipient) throws StorageFailedException {
     log(content.getTimestamp(), "Story message.");
 
-    if (!threadRecipient.isActiveGroup() && !(senderRecipient.isProfileSharing() || senderRecipient.isSystemContact())) {
+    if (threadRecipient.isInactiveGroup()) {
+      warn(content.getTimestamp(), "Dropping a group story from a group we're no longer in.");
+      return;
+    }
+
+    if (threadRecipient.isGroup() && !SignalDatabase.groups().isCurrentMember(threadRecipient.requireGroupId().requirePush(), senderRecipient.getId())) {
+      warn(content.getTimestamp(), "Dropping a group story from a user who's no longer a member.");
+      return;
+    }
+
+    if (!threadRecipient.isGroup() && !(senderRecipient.isProfileSharing() || senderRecipient.isSystemContact())) {
       warn(content.getTimestamp(), "Dropping story from an untrusted source.");
       return;
     }

app/src/main/java/org/thoughtcrime/securesms/recipients/Recipient.java

@@ -877,6 +877,10 @@ public class Recipient {
     return Stream.of(getParticipantIds()).anyMatch(p -> p.equals(selfId));
   }
 
+  public boolean isInactiveGroup() {
+    return isGroup() && !isActiveGroup();
+  }
+
   public @NonNull List<RecipientId> getParticipantIds() {
     return new ArrayList<>(participantIds);
   }

app/src/main/java/org/thoughtcrime/securesms/stories/landing/StoriesLandingRepository.kt

@@ -44,12 +44,12 @@ class StoriesLandingRepository(context: Context) {
 
         stories.forEach {
           val recipient = Recipient.resolved(it.recipientId)
-          if (recipient.isDistributionList || it.isOutgoing) {
+          if (recipient.isDistributionList || (it.isOutgoing && !recipient.isInactiveGroup())) {
             val list = mapping[myStories] ?: emptyList()
             mapping[myStories] = list + it
           }
 
-          if (!recipient.isDistributionList && !recipient.isBlocked) {
+          if (!recipient.isDistributionList && !recipient.isBlocked && !recipient.isInactiveGroup()) {
             val list = mapping[recipient] ?: emptyList()
             mapping[recipient] = list + it
           }