1 files changed, 18 insertions, 2 deletions
diff --git a/app/lib/activitypub/activity/delete.rb b/app/lib/activitypub/activity/delete.rb
index 8270fed1b..dc76dd3e2 100644
--- a/app/lib/activitypub/activity/delete.rb
+++ b/app/lib/activitypub/activity/delete.rb
@@ -21,11 +21,14 @@ class ActivityPub::Activity::Delete < ActivityPub::Activity
   def delete_note
     return if object_uri.nil?
 
+    unless invalid_origin?(object_uri)
+      RedisLock.acquire(lock_options) { |_lock| delete_later!(object_uri) }
+      Tombstone.find_or_create_by(uri: object_uri, account: @account)
+    end
+
     @status   = Status.find_by(uri: object_uri, account: @account)
     @status ||= Status.find_by(uri: @object['atomUri'], account: @account) if @object.is_a?(Hash) && @object['atomUri'].present?
 
-    delete_later!(object_uri)
-
     return if @status.nil?
 
     if @status.public_visibility? || @status.unlisted_visibility?
@@ -68,4 +71,17 @@ class ActivityPub::Activity::Delete < ActivityPub::Activity
   def payload
     @payload ||= Oj.dump(@json)
   end
+
+  def lock_options
+    { redis: Redis.current, key: "create:#{object_uri}" }
+  end
+
+  def invalid_origin?(url)
+    return true if unsupported_uri_scheme?(url)
+
+    needle   = Addressable::URI.parse(url).host
+    haystack = Addressable::URI.parse(@account.uri).host
+
+    !haystack.casecmp(needle).zero?
+  end
 end