From ba4d1c98440616aad97ef26170da0127b12722b0 Mon Sep 17 00:00:00 2001
From: Greyson Parrelli <greyson@signal.org>
Date: Wed, 25 Aug 2021 14:20:49 -0400
Subject: [PATCH] Add a failsafe to prevent non-admin sends in announcement
 groups.

---
 .../org/thoughtcrime/securesms/jobs/PushGroupSendJob.java   | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/app/src/main/java/org/thoughtcrime/securesms/jobs/PushGroupSendJob.java b/app/src/main/java/org/thoughtcrime/securesms/jobs/PushGroupSendJob.java
index 4e095a501..0650dae3d 100644
--- a/app/src/main/java/org/thoughtcrime/securesms/jobs/PushGroupSendJob.java
+++ b/app/src/main/java/org/thoughtcrime/securesms/jobs/PushGroupSendJob.java
@@ -173,6 +173,12 @@ public final class PushGroupSendJob extends PushSendJob {
       throw new MmsException("No GV1 messages can be sent anymore!");
     }
 
+    Optional<GroupDatabase.GroupRecord> groupRecord = DatabaseFactory.getGroupDatabase(context).getGroup(groupRecipient.requireGroupId());
+
+    if (groupRecord.isPresent() && groupRecord.get().isAnnouncementGroup() && !groupRecord.get().isAdmin(Recipient.self())) {
+      throw new MmsException("Non-admins cannot send messages in announcement groups!");
+    }
+
     try {
       log(TAG, String.valueOf(message.getSentTimeMillis()), "Sending message: " + messageId + ", Recipient: " + message.getRecipient().getId() + ", Thread: " + threadId + ", Attachments: " + buildAttachmentString(message.getAttachments()));