1 files changed, 11 insertions, 33 deletions

diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index 142af1a13..6d49f0141 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -516,52 +516,30 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   end
 
   def handle_incoming(
-        %{
-          "type" => "Undo",
-          "object" => %{"type" => "Follow", "object" => followed},
-          "actor" => follower,
-          "id" => id
-        } = _data,
-        _options
-      ) do
-    with %User{local: true} = followed <- User.get_cached_by_ap_id(followed),
-         {:ok, %User{} = follower} <- User.get_or_fetch_by_ap_id(follower),
-         {:ok, activity} <- ActivityPub.unfollow(follower, followed, id, false) do
-      User.unfollow(follower, followed)
-      {:ok, activity}
-    else
-      _e -> :error
-    end
-  end
-
-  def handle_incoming(
-        %{
-          "type" => "Undo",
-          "object" => %{"type" => type}
-        } = data,
+        %{"type" => "Undo", "object" => %{"type" => objtype, "id" => object_id}} = data,
         _options
       )
-      when type in ["Like", "EmojiReact", "Announce", "Block"] do
-    with {:ok, activity, _} <- Pipeline.common_pipeline(data, local: false) do
+      when objtype in ~w[Like EmojiReact Announce Block Follow] do
+    with {:ok, %User{}} <- ObjectValidator.fetch_actor(data),
+         {_, %Activity{}} <- {:exists, Activity.get_by_ap_id(object_id)},
+         {:ok, activity, _} <- Pipeline.common_pipeline(data, local: false) do
       {:ok, activity}
+    else
+      {:error, _} = e -> e
+      e -> {:error, e}
     end
   end
 
   # For Undos that don't have the complete object attached, try to find it in our database.
-  def handle_incoming(
-        %{
-          "type" => "Undo",
-          "object" => object
-        } = activity,
-        options
-      )
+  def handle_incoming(%{"type" => "Undo", "object" => object} = activity, options)
       when is_binary(object) do
     with %Activity{data: data} <- Activity.get_by_ap_id(object) do
       activity
       |> Map.put("object", data)
       |> handle_incoming(options)
     else
-      _e -> :error
+      {:error, _} = e -> e
+      e -> {:error, e}
     end
   end