Handle DTLS close_notify alert

Author: mickel8

lib/ex_webrtc/dtls_transport.ex

@@ -327,6 +327,13 @@ defmodule ExWebRTC.DTLSTransport do
       {:ok, state} ->
         {:noreply, state}
 
+      {:error, :peer_closed_for_writing} ->
+        # See W3C WebRTC sec. 5.5.1
+        # peer_closed_for_writing is returned when the remote side
+        # sends close_notify alert
+        state = update_dtls_state(state, :closed)
+        {:noreply, state}
+
       {:error, _reason} ->
         # See W3C WebRTC sec. 5.5.
         state = update_dtls_state(state, :failed)

lib/ex_webrtc/peer_connection.ex

@@ -63,7 +63,7 @@ defmodule ExWebRTC.PeerConnection do
 
   For the exact meaning, refer to the [RTCDtlsTransport: state property](https://developer.mozilla.org/en-US/docs/Web/API/RTCDtlsTransport/state)
   """
-  @type dtls_transport_state() :: :new | :connecting | :connected | :failed
+  @type dtls_transport_state() :: :new | :connecting | :connected | :closed | :failed
 
   @typedoc """
   Possible signaling states.
@@ -105,8 +105,8 @@ defmodule ExWebRTC.PeerConnection do
            | {:track_muted, MediaStreamTrack.id()}
            | {:track_ended, MediaStreamTrack.id()}
            | {:data, DataChannel.ref(), binary()}
-           | {:rtp, MediaStreamTrack.id(), String.t() | nil, ExRTP.Packet.t()}}
-          | {:rtcp, [{MediaStreamTrack.id() | nil, ExRTCP.Packet.packet()}]}
+           | {:rtp, MediaStreamTrack.id(), String.t() | nil, ExRTP.Packet.t()}
+           | {:rtcp, [{MediaStreamTrack.id() | nil, ExRTCP.Packet.packet()}]}}
 
   #### NON-MDN-API ####
 

test/ex_webrtc/dtls_transport_test.exs

@@ -278,6 +278,13 @@ defmodule ExWebRTC.DTLSTransportTest do
     refute_receive {:mock_ice, _datachannel_packet}
   end
 
+  # test "closes on receiving close_notify DTLS alert", %{
+  #   dtls: dtls,
+  #   ice_transport: ice_transport,
+  #   ice_pid: ice_pid
+  # } do
+  # end
+
   defp check_handshake(dtls, ice_transport, ice_pid, remote_dtls) do
     assert_receive {:mock_ice, packets}
 

test/ex_webrtc/peer_connection_test.exs

@@ -1156,6 +1156,31 @@ defmodule ExWebRTC.PeerConnectionTest do
     end
   end
 
+  @tag :debug
+  test "" do
+    {:ok, pc1} = PeerConnection.start_link()
+    {:ok, _sender} = PeerConnection.add_track(pc1, MediaStreamTrack.new(:video))
+    {:ok, offer} = PeerConnection.create_offer(pc1)
+    :ok = PeerConnection.set_local_description(pc1, offer)
+
+    IO.inspect(offer.sdp, limit: :infinity)
+
+    {:ok, pc2} = PeerConnection.start_link()
+    {:ok, _sender} = PeerConnection.add_track(pc2, MediaStreamTrack.new(:video))
+    :ok = PeerConnection.set_remote_description(pc2, offer)
+    {:ok, answer} = PeerConnection.create_answer(pc2)
+
+    IO.inspect(answer.sdp, limit: :infinity)
+
+    :ok = PeerConnection.set_remote_description(pc1, answer)
+
+    {:ok, _sender} = PeerConnection.add_track(pc1, MediaStreamTrack.new(:video))
+    {:ok, offer} = PeerConnection.create_offer(pc1)
+    :ok = PeerConnection.set_local_description(pc1, offer)
+
+    IO.inspect(offer.sdp, limit: :infinity)
+  end
+
   describe "send data in both directions on a single transceiver" do
     test "using one negotiation" do
       {:ok, pc1} = PeerConnection.start_link()