From 3d742c3c1af69a9526c12a171663630b3439b5cc Mon Sep 17 00:00:00 2001 From: Alex Gleason Date: Thu, 18 Mar 2021 15:31:50 -0500 Subject: [PATCH 1/3] SimplePolicy: filter nested objects --- lib/pleroma/web/activity_pub/mrf/simple_policy.ex | 11 ++++++++++- .../web/activity_pub/mrf/simple_policy_test.exs | 12 ++++++++++++ 2 files changed, 22 insertions(+), 1 deletion(-) diff --git a/lib/pleroma/web/activity_pub/mrf/simple_policy.ex b/lib/pleroma/web/activity_pub/mrf/simple_policy.ex index bb3838d2c..b3e5d814d 100644 --- a/lib/pleroma/web/activity_pub/mrf/simple_policy.ex +++ b/lib/pleroma/web/activity_pub/mrf/simple_policy.ex @@ -181,6 +181,14 @@ defmodule Pleroma.Web.ActivityPub.MRF.SimplePolicy do defp check_banner_removal(_actor_info, object), do: {:ok, object} + defp check_object(%{"object" => object} = activity) when is_map(object) do + with {:ok, _object} <- filter(object) do + {:ok, activity} + end + end + + defp check_object(object), do: {:ok, object} + @impl true def filter(%{"type" => "Delete", "actor" => actor} = object) do %{host: actor_host} = URI.parse(actor) @@ -206,7 +214,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.SimplePolicy do {:ok, object} <- check_media_nsfw(actor_info, object), {:ok, object} <- check_ftl_removal(actor_info, object), {:ok, object} <- check_followers_only(actor_info, object), - {:ok, object} <- check_report_removal(actor_info, object) do + {:ok, object} <- check_report_removal(actor_info, object), + {:ok, object} <- check_object(object) do {:ok, object} else {:reject, nil} -> {:reject, "[SimplePolicy]"} diff --git a/test/pleroma/web/activity_pub/mrf/simple_policy_test.exs b/test/pleroma/web/activity_pub/mrf/simple_policy_test.exs index f48e5b39b..b6d9f2ded 100644 --- a/test/pleroma/web/activity_pub/mrf/simple_policy_test.exs +++ b/test/pleroma/web/activity_pub/mrf/simple_policy_test.exs @@ -260,6 +260,18 @@ defmodule Pleroma.Web.ActivityPub.MRF.SimplePolicyTest do assert {:reject, _} = SimplePolicy.filter(remote_user) end + + test "reject Announce when object would be rejected" do + clear_config([:mrf_simple, :reject], ["blocked.tld"]) + + announce = %{ + "type" => "Announce", + "actor" => "https://okay.tld/users/alice", + "object" => %{"type" => "Note", "actor" => "https://blocked.tld/users/bob"} + } + + assert {:reject, _} = SimplePolicy.filter(announce) + end end describe "when :followers_only" do From c16c7fdb8794df8558cf8fbe4231d8f9ec01bb6d Mon Sep 17 00:00:00 2001 From: Alex Gleason Date: Thu, 29 Apr 2021 11:51:49 -0500 Subject: [PATCH 2/3] SimplePolicy: filter string Objects --- lib/pleroma/web/activity_pub/mrf/simple_policy.ex | 15 ++++++++++++++- .../web/activity_pub/mrf/simple_policy_test.exs | 12 ++++++++++++ 2 files changed, 26 insertions(+), 1 deletion(-) diff --git a/lib/pleroma/web/activity_pub/mrf/simple_policy.ex b/lib/pleroma/web/activity_pub/mrf/simple_policy.ex index b3e5d814d..b07d70401 100644 --- a/lib/pleroma/web/activity_pub/mrf/simple_policy.ex +++ b/lib/pleroma/web/activity_pub/mrf/simple_policy.ex @@ -181,7 +181,7 @@ defmodule Pleroma.Web.ActivityPub.MRF.SimplePolicy do defp check_banner_removal(_actor_info, object), do: {:ok, object} - defp check_object(%{"object" => object} = activity) when is_map(object) do + defp check_object(%{"object" => object} = activity) do with {:ok, _object} <- filter(object) do {:ok, activity} end @@ -240,6 +240,19 @@ defmodule Pleroma.Web.ActivityPub.MRF.SimplePolicy do end end + def filter(object) when is_binary(object) do + uri = URI.parse(object) + + with {:ok, object} <- check_accept(uri, object), + {:ok, object} <- check_reject(uri, object) do + {:ok, object} + else + {:reject, nil} -> {:reject, "[SimplePolicy]"} + {:reject, _} = e -> e + _ -> {:reject, "[SimplePolicy]"} + end + end + def filter(object), do: {:ok, object} @impl true diff --git a/test/pleroma/web/activity_pub/mrf/simple_policy_test.exs b/test/pleroma/web/activity_pub/mrf/simple_policy_test.exs index b6d9f2ded..8024a2459 100644 --- a/test/pleroma/web/activity_pub/mrf/simple_policy_test.exs +++ b/test/pleroma/web/activity_pub/mrf/simple_policy_test.exs @@ -272,6 +272,18 @@ defmodule Pleroma.Web.ActivityPub.MRF.SimplePolicyTest do assert {:reject, _} = SimplePolicy.filter(announce) end + + test "reject by URI object" do + clear_config([:mrf_simple, :reject], ["blocked.tld"]) + + announce = %{ + "type" => "Announce", + "actor" => "https://okay.tld/users/alice", + "object" => "https://blocked.tld/activities/1" + } + + assert {:reject, _} = SimplePolicy.filter(announce) + end end describe "when :followers_only" do From 20878c7f9913e1501821356f24e97c2c42b00a41 Mon Sep 17 00:00:00 2001 From: Alex Gleason Date: Fri, 2 Apr 2021 12:18:35 -0500 Subject: [PATCH 3/3] CHANGELOG: SimplePolicy embedded objects are now checked --- CHANGELOG.md | 1 + 1 file changed, 1 insertion(+) diff --git a/CHANGELOG.md b/CHANGELOG.md index 9a0171763..150cd4147 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -25,6 +25,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/). - Applying ConcurrentLimiter settings via AdminAPI - User login failures if their `notification_settings` were in a NULL state. - Mix task `pleroma.user delete_activities` query transaction timeout is now :infinity +- MRF (`SimplePolicy`): Embedded objects are now checked. If any embedded object would be rejected, its parent is rejected. This fixes Announces leaking posts from blocked domains. ## [2.3.0] - 2020-03-01