Merge branch 'feature/hellthread-mitigation' into 'develop'

implement hellthread mitigation

Closes #474

See merge request pleroma/pleroma!588

1 files changed, 18 insertions, 0 deletions

diff --git a/lib/pleroma/web/activity_pub/mrf/hellthread_policy.ex b/lib/pleroma/web/activity_pub/mrf/hellthread_policy.ex
new file mode 100644
index 000000000..55d6ff3f0
--- /dev/null
+++ b/lib/pleroma/web/activity_pub/mrf/hellthread_policy.ex
@@ -0,0 +1,18 @@
+defmodule Pleroma.Web.ActivityPub.MRF.HellthreadPolicy do
+  @behaviour Pleroma.Web.ActivityPub.MRF
+
+  @impl true
+  def filter(%{"type" => "Create"} = object) do
+    threshold = Pleroma.Config.get([:mrf_hellthread, :threshold])
+    recipients = (object["to"] || []) ++ (object["cc"] || [])
+
+    if length(recipients) > threshold do
+      {:reject, nil}
+    else
+      {:ok, object}
+    end
+  end
+
+  @impl true
+  def filter(object), do: {:ok, object}
+end