defmodule Pleroma.Object.Containment do @moduledoc """ This module contains some useful functions for containing objects to specific origins and determining those origins. They previously lived in the ActivityPub `Transmogrifier` module. Object containment is an important step in validating remote objects to prevent spoofing, therefore removal of object containment functions is NOT recommended. """ def get_actor(%{"actor" => actor}) when is_binary(actor) do actor end def get_actor(%{"actor" => actor}) when is_list(actor) do if is_binary(Enum.at(actor, 0)) do Enum.at(actor, 0) else Enum.find(actor, fn %{"type" => type} -> type in ["Person", "Service", "Application"] end) |> Map.get("id") end end def get_actor(%{"actor" => %{"id" => id}}) when is_bitstring(id) do id end def get_actor(%{"actor" => nil, "attributedTo" => actor}) when not is_nil(actor) do get_actor(%{"actor" => actor}) end @doc """ Checks that an imported AP object's actor matches the domain it came from. """ def contain_origin(_id, %{"actor" => nil}), do: :error def contain_origin(id, %{"actor" => _actor} = params) do id_uri = URI.parse(id) actor_uri = URI.parse(get_actor(params)) if id_uri.host == actor_uri.host do :ok else :error end end def contain_origin_from_id(_id, %{"id" => nil}), do: :error def contain_origin_from_id(id, %{"id" => other_id} = _params) do id_uri = URI.parse(id) other_uri = URI.parse(other_id) if id_uri.host == other_uri.host do :ok else :error end end end