Add Resource Binding support to xmpp_stream_out

src/xmpp_stream_out.erl

@@ -29,7 +29,7 @@
 
 %% API
 -export([start/3, start_link/3, call/3, cast/2, reply/2, connect/1,
-	 stop/1, send/2, close/1, close/2, establish/1, format_error/1,
+	 stop/1, send/2, close/1, close/2, bind/2, establish/1, format_error/1,
 	 set_timeout/2, get_transport/1, change_shaper/2]).
 %% gen_server callbacks
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
@@ -61,6 +61,7 @@
 		       {tls, tls_error_reason()} |
 		       {pkix, binary()} |
 		       {auth, atom() | binary() | string()} |
+		       {bind, stanza_error()} |
 		       {socket, socket_error_reason()} |
 		       internal_failure.
 -export_type([state/0, stop_reason/0]).
@@ -82,6 +83,8 @@
 -callback handle_unauthenticated_features(stream_features(), state()) -> state().
 -callback handle_auth_success(cyrsasl:mechanism(), state()) -> state().
 -callback handle_auth_failure(cyrsasl:mechanism(), binary(), state()) -> state().
+-callback handle_bind_success(state()) -> state().
+-callback handle_bind_failure(stanza_error(), state()) -> state().
 -callback handle_packet(xmpp_element(), state()) -> state().
 -callback tls_options(state()) -> [proplists:property()].
 -callback tls_required(state()) -> boolean().
@@ -111,6 +114,8 @@
 		     handle_unauthenticated_features/2,
 		     handle_auth_success/2,
 		     handle_auth_failure/3,
+		     handle_bind_success/1,
+		     handle_bind_failure/2,
 		     handle_packet/2,
 		     tls_options/1,
 		     tls_required/1,
@@ -176,6 +181,10 @@ close(_) ->
 close(Pid, Reason) ->
     cast(Pid, {close, Reason}).
 
+-spec bind(state(), stream_features()) -> state().
+bind(#{stream_authenticated := true} = State, StreamFeatures) ->
+    process_bind(StreamFeatures, State).
+
 -spec establish(state()) -> state().
 establish(State) ->
     process_stream_established(State).
@@ -221,6 +230,8 @@ format_error({stream, {in, #stream_error{} = Err}}) ->
     format("Stream closed by peer: ~s", [xmpp:format_stream_error(Err)]);
 format_error({stream, {out, #stream_error{} = Err}}) ->
     format("Stream closed by us: ~s", [xmpp:format_stream_error(Err)]);
+format_error({bind, #stanza_error{} = Err}) ->
+    format("Resource binding failure: ~s", [xmpp:format_stanza_error(Err)]);
 format_error({tls, Reason}) ->
     format("TLS failed: ~s", [format_tls_error(Reason)]);
 format_error({auth, Reason}) ->
@@ -515,6 +526,8 @@ process_element(Pkt, #{stream_state := StateName} = State) ->
 	       is_record(Pkt, handshake) ->
 	    %% Do not pass this crap upstream
 	    State;
+	_ when StateName == wait_for_bind_response ->
+	    process_bind_response(Pkt, State);
 	_ ->
 	    process_packet(Pkt, State)
     end.
@@ -522,10 +535,9 @@ process_element(Pkt, #{stream_state := StateName} = State) ->
 -spec process_features(stream_features(), state()) -> state().
 process_features(StreamFeatures,
 		 #{stream_authenticated := true} = State) ->
-    State1 = try callback(handle_authenticated_features, StreamFeatures, State)
+    try callback(handle_authenticated_features, StreamFeatures, State)
-	     catch _:{?MODULE, undef} -> State
+    catch _:{?MODULE, undef} -> process_bind(StreamFeatures, State)
-	     end,
+    end;
-    process_stream_established(State1);
 process_features(StreamFeatures,
 		 #{stream_encrypted := Encrypted,
 		   lang := Lang, xmlns := NS} = State) ->
@@ -679,6 +691,59 @@ process_sasl_failure(Reason, State) ->
     catch _:{?MODULE, undef} -> process_stream_end({auth, Reason}, State)
     end.
 
+-spec process_bind(stream_features(), state()) -> state().
+process_bind(StreamFeatures, #{lang := Lang, xmlns := ?NS_CLIENT,
+			       user := U, server := S, resource := R,
+			       stream_state := StateName} = State)
+  when StateName /= established, StateName /= disconnected ->
+    case xmpp:has_subtag(StreamFeatures, #bind{}) of
+	true ->
+	    JID = jid:make(U, S, R),
+	    ID = new_id(),
+	    Pkt = #iq{from = JID, to = jid:remove_resource(JID),
+		      id = ID, type = set,
+		      sub_els = [#bind{resource = R}]},
+	    State1 = State#{stream_state => wait_for_bind_response,
+			    bind_id => ID},
+	    send_pkt(State1, Pkt);
+	false ->
+	    Txt = <<"Missing resource binding feature">>,
+	    send_pkt(State, xmpp:serr_invalid_xml(Txt, Lang))
+    end;
+process_bind(_, State) ->
+    process_stream_established(State).
+
+-spec process_bind_response(xmpp_element(), state()) -> state().
+process_bind_response(#iq{type = result, id = ID} = IQ,
+		      #{lang := Lang, bind_id := ID} = State) ->
+    State1 = maps:remove(bind_id, State),
+    try xmpp:try_subtag(IQ, #bind{}) of
+	#bind{jid = #jid{user = U, server = S, resource = R}} ->
+	    State2 = State1#{user => U, server => S, resource => R},
+	    State3 = try callback(handle_bind_success, State2)
+		     catch _:{?MODULE, undef} -> State2
+		     end,
+	    process_stream_established(State3);
+	#bind{} ->
+	    Txt = <<"Missing <jid/> element in resource binding response">>,
+	    send_pkt(State1, xmpp:serr_invalid_xml(Txt, Lang));
+	false ->
+	    Txt = <<"Missing <bind/> element in resource binding response">>,
+	    send_pkt(State1, xmpp:serr_invalid_xml(Txt, Lang))
+    catch _:{xmpp_codec, Why} ->
+	    Txt = xmpp:io_format_error(Why),
+	    send_pkt(State1, xmpp:serr_invalid_xml(Txt, Lang))
+    end;
+process_bind_response(#iq{type = error, id = ID} = IQ,
+		      #{bind_id := ID} = State) ->
+    Err = xmpp:get_error(IQ),
+    State1 = maps:remove(bind_id, State),
+    try callback(handle_bind_failure, Err, State1)
+    catch _:{?MODULE, undef} -> process_stream_end({bind, Err}, State1)
+    end;
+process_bind_response(Pkt, State) ->
+    process_packet(Pkt, State).
+
 -spec process_packet(xmpp_element(), state()) -> state().
 process_packet(Pkt, State) ->
     try callback(handle_packet, Pkt, State)