Merge branch 'feature/jobs' into 'develop'

[akkoma] / lib / pleroma / web / activity_pub / mrf / hellthread_policy.ex

diff --git a/lib/pleroma/web/activity_pub/mrf/hellthread_policy.ex b/lib/pleroma/web/activity_pub/mrf/hellthread_policy.ex
index 0e09181263d2039564877301320cf6a7e89c3cb0..6736f3cb905a7e0c8edc7cdce22190c9c99c7840 100644 (file)
--- a/lib/pleroma/web/activity_pub/mrf/hellthread_policy.ex
+++ b/lib/pleroma/web/activity_pub/mrf/hellthread_policy.ex
@@ -1,15 +1,88 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
 defmodule Pleroma.Web.ActivityPub.MRF.HellthreadPolicy do
+  alias Pleroma.User
   @behaviour Pleroma.Web.ActivityPub.MRF
 
+  defp delist_message(message, threshold) when threshold > 0 do
+    follower_collection = User.get_cached_by_ap_id(message["actor"]).follower_address
+
+    follower_collection? = Enum.member?(message["to"] ++ message["cc"], follower_collection)
+
+    message =
+      case get_recipient_count(message) do
+        {:public, recipients}
+        when follower_collection? and recipients > threshold ->
+          message
+          |> Map.put("to", [follower_collection])
+          |> Map.put("cc", ["https://www.w3.org/ns/activitystreams#Public"])
+
+        {:public, recipients} when recipients > threshold ->
+          message
+          |> Map.put("to", [])
+          |> Map.put("cc", ["https://www.w3.org/ns/activitystreams#Public"])
+
+        _ ->
+          message
+      end
+
+    {:ok, message}
+  end
+
+  defp delist_message(message, _threshold), do: {:ok, message}
+
+  defp reject_message(message, threshold) when threshold > 0 do
+    with {_, recipients} <- get_recipient_count(message) do
+      if recipients > threshold do
+        {:reject, nil}
+      else
+        {:ok, message}
+      end
+    end
+  end
+
+  defp reject_message(message, _threshold), do: {:ok, message}
+
+  defp get_recipient_count(message) do
+    recipients = (message["to"] || []) ++ (message["cc"] || [])
+    follower_collection = User.get_cached_by_ap_id(message["actor"]).follower_address
+
+    if Enum.member?(recipients, "https://www.w3.org/ns/activitystreams#Public") do
+      recipients =
+        recipients
+        |> List.delete("https://www.w3.org/ns/activitystreams#Public")
+        |> List.delete(follower_collection)
+
+      {:public, length(recipients)}
+    else
+      recipients =
+        recipients
+        |> List.delete(follower_collection)
+
+      {:not_public, length(recipients)}
+    end
+  end
+
   @impl true
-  def filter(object) do
+  def filter(%{"type" => "Create"} = message) do
+    reject_threshold =
+      Pleroma.Config.get(
+        [:mrf_hellthread, :reject_threshold],
+        Pleroma.Config.get([:mrf_hellthread, :threshold])
+      )
 
-    policy = Pleroma.Config.get(:mrf_hellthreadmitigation)
+    delist_threshold = Pleroma.Config.get([:mrf_hellthread, :delist_threshold])
 
-    if (length(object["to"]) + length(object["cc"])) > Keyword.get(policy, :threshold) do
-      {:reject, nil}
+    with {:ok, message} <- reject_message(message, reject_threshold),
+         {:ok, message} <- delist_message(message, delist_threshold) do
+      {:ok, message}
     else
-      {:ok, object}
+      _e -> {:reject, nil}
     end
   end
-end
\ No newline at end of file
+
+  @impl true
+  def filter(message), do: {:ok, message}
+end