Signature: Handle non-ap ids in key ids.

Mastodon and Gab sometimes send the format `acct:name@server`.

1 files changed, 15 insertions, 3 deletions

diff --git a/lib/pleroma/signature.ex b/lib/pleroma/signature.ex
index 6b0b2c969..d01728361 100644
--- a/lib/pleroma/signature.ex
+++ b/lib/pleroma/signature.ex
@@ -8,6 +8,7 @@ defmodule Pleroma.Signature do
   alias Pleroma.Keys
   alias Pleroma.User
   alias Pleroma.Web.ActivityPub.ActivityPub
+  alias Pleroma.Web.ActivityPub.ObjectValidators.Types
 
   def key_id_to_actor_id(key_id) do
     uri =
@@ -21,12 +22,23 @@ defmodule Pleroma.Signature do
         uri
       end
 
-    URI.to_string(uri)
+    maybe_ap_id = URI.to_string(uri)
+
+    case Types.ObjectID.cast(maybe_ap_id) do
+      {:ok, ap_id} ->
+        {:ok, ap_id}
+
+      _ ->
+        case Pleroma.Web.WebFinger.finger(maybe_ap_id) do
+          %{"ap_id" => ap_id} -> {:ok, ap_id}
+          _ -> {:error, maybe_ap_id}
+        end
+    end
   end
 
   def fetch_public_key(conn) do
     with %{"keyId" => kid} <- HTTPSignatures.signature_for_conn(conn),
-         actor_id <- key_id_to_actor_id(kid),
+         {:ok, actor_id} <- key_id_to_actor_id(kid),
          {:ok, public_key} <- User.get_public_key_for_ap_id(actor_id) do
       {:ok, public_key}
     else
@@ -37,7 +49,7 @@ defmodule Pleroma.Signature do
 
   def refetch_public_key(conn) do
     with %{"keyId" => kid} <- HTTPSignatures.signature_for_conn(conn),
-         actor_id <- key_id_to_actor_id(kid),
+         {:ok, actor_id} <- key_id_to_actor_id(kid),
          {:ok, _user} <- ActivityPub.make_user_from_ap_id(actor_id),
          {:ok, public_key} <- User.get_public_key_for_ap_id(actor_id) do
       {:ok, public_key}