From dfcfb184b10428af8d37492e64f271c0275fc2c9 Mon Sep 17 00:00:00 2001 From: William Pitcock Date: Sat, 17 Nov 2018 21:22:30 +0000 Subject: [PATCH] activitypub: transmogrifier: make deletes secure --- .../web/activity_pub/transmogrifier.ex | 11 +++++++--- test/web/activity_pub/transmogrifier_test.exs | 20 +++++++++++++++++++ 2 files changed, 28 insertions(+), 3 deletions(-) diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex index 1f886839e..5864855b0 100644 --- a/lib/pleroma/web/activity_pub/transmogrifier.ex +++ b/lib/pleroma/web/activity_pub/transmogrifier.ex @@ -467,15 +467,20 @@ def handle_incoming( end end - # TODO: Make secure. + # TODO: We presently assume that any actor on the same origin domain as the object being + # deleted has the rights to delete that object. A better way to validate whether or not + # the object should be deleted is to refetch the object URI, which should return either + # an error or a tombstone. This would allow us to verify that a deletion actually took + # place. def handle_incoming( - %{"type" => "Delete", "object" => object_id, "actor" => actor, "id" => _id} = data + %{"type" => "Delete", "object" => object_id, "actor" => _actor, "id" => _id} = data ) do object_id = Utils.get_ap_id(object_id) with actor <- get_actor(data), - %User{} = _actor <- User.get_or_fetch_by_ap_id(actor), + %User{} = actor <- User.get_or_fetch_by_ap_id(actor), {:ok, object} <- get_obj_helper(object_id) || fetch_obj_helper(object_id), + :ok <- contain_origin(actor.ap_id, object.data), {:ok, activity} <- ActivityPub.delete(object, false) do {:ok, activity} else diff --git a/test/web/activity_pub/transmogrifier_test.exs b/test/web/activity_pub/transmogrifier_test.exs index 9174d9b76..829da0a65 100644 --- a/test/web/activity_pub/transmogrifier_test.exs +++ b/test/web/activity_pub/transmogrifier_test.exs @@ -361,6 +361,26 @@ test "it works for incoming deletes" do refute Repo.get(Activity, activity.id) end + test "it fails for incoming deletes with spoofed origin" do + activity = insert(:note_activity) + + data = + File.read!("test/fixtures/mastodon-delete.json") + |> Poison.decode!() + + object = + data["object"] + |> Map.put("id", activity.data["object"]["id"]) + + data = + data + |> Map.put("object", object) + + :error = Transmogrifier.handle_incoming(data) + + assert Repo.get(Activity, activity.id) + end + test "it works for incoming unannounces with an existing notice" do user = insert(:user) {:ok, activity} = CommonAPI.post(user, %{"status" => "hey"})