XEP-0198: Add 'h' attribute to <failed/> element

If a resume request is rejected because the session timed out, indicate
the number of handled stanzas as per version 1.5 of XEP-0198.

include/ejabberd_sm.hrl

@@ -3,10 +3,11 @@
 
 -record(session, {sid, usr, us, priority, info}).
 -record(session_counter, {vhost, count}).
--type sid() :: {erlang:timestamp(), pid()}.
+-type sid() :: {erlang:timestamp(), pid()} | {erlang:timestamp(), undefined}.
 -type ip() :: {inet:ip_address(), inet:port_number()} | undefined.
 -type info() :: [{conn, atom()} | {ip, ip()} | {node, atom()}
-                 | {oor, boolean()} | {auth_module, atom()}].
+                 | {oor, boolean()} | {auth_module, atom()}
+                 | {num_stanzas_in, non_neg_integer()}].
 -type prio() :: undefined | integer().
 
 -endif.

src/ejabberd_c2s.erl

@@ -166,27 +166,32 @@
 	(Xmlns == ?NS_STREAM_MGMT_2) or
 	(Xmlns == ?NS_STREAM_MGMT_3)).
 
--define(MGMT_FAILED(Condition, Xmlns),
+-define(MGMT_FAILED(Condition, Attrs),
 	#xmlel{name = <<"failed">>,
-	       attrs = [{<<"xmlns">>, Xmlns}],
+	       attrs = Attrs,
 	       children = [#xmlel{name = Condition,
 				  attrs = [{<<"xmlns">>, ?NS_STANZAS}],
 				  children = []}]}).
 
 -define(MGMT_BAD_REQUEST(Xmlns),
-	?MGMT_FAILED(<<"bad-request">>, Xmlns)).
-
--define(MGMT_ITEM_NOT_FOUND(Xmlns),
-	?MGMT_FAILED(<<"item-not-found">>, Xmlns)).
+	?MGMT_FAILED(<<"bad-request">>, [{<<"xmlns">>, Xmlns}])).
 
 -define(MGMT_SERVICE_UNAVAILABLE(Xmlns),
-	?MGMT_FAILED(<<"service-unavailable">>, Xmlns)).
+	?MGMT_FAILED(<<"service-unavailable">>, [{<<"xmlns">>, Xmlns}])).
 
 -define(MGMT_UNEXPECTED_REQUEST(Xmlns),
-	?MGMT_FAILED(<<"unexpected-request">>, Xmlns)).
+	?MGMT_FAILED(<<"unexpected-request">>, [{<<"xmlns">>, Xmlns}])).
 
 -define(MGMT_UNSUPPORTED_VERSION(Xmlns),
-	?MGMT_FAILED(<<"unsupported-version">>, Xmlns)).
+	?MGMT_FAILED(<<"unsupported-version">>, [{<<"xmlns">>, Xmlns}])).
+
+-define(MGMT_ITEM_NOT_FOUND(Xmlns),
+	?MGMT_FAILED(<<"item-not-found">>, [{<<"xmlns">>, Xmlns}])).
+
+-define(MGMT_ITEM_NOT_FOUND_H(Xmlns, NumStanzasIn),
+	?MGMT_FAILED(<<"item-not-found">>,
+		     [{<<"xmlns">>, Xmlns},
+		      {<<"h">>, jlib:integer_to_binary(NumStanzasIn)}])).
 
 %%%----------------------------------------------------------------------
 %%% API
@@ -1280,7 +1285,7 @@ wait_for_resume({xmlstreamelement, _El} = Event, StateData) ->
 wait_for_resume(timeout, StateData) ->
     ?DEBUG("Timed out waiting for resumption of stream for ~s",
 	   [jid:to_string(StateData#state.jid)]),
-    {stop, normal, StateData};
+    {stop, normal, StateData#state{mgmt_state = timeout}};
 wait_for_resume(Event, StateData) ->
     ?DEBUG("Ignoring event while waiting for resumption: ~p", [Event]),
     fsm_next_state(wait_for_resume, StateData).
@@ -1791,6 +1796,18 @@ terminate(_Reason, StateName, StateData) ->
 			     presence_broadcast(StateData, From,
 						StateData#state.pres_a, Packet)
 		       end,
+		       case StateData#state.mgmt_state of
+			 timeout ->
+			     Info = [{num_stanzas_in,
+				      StateData#state.mgmt_stanzas_in}],
+			     ejabberd_sm:set_offline_info(StateData#state.sid,
+							  StateData#state.user,
+							  StateData#state.server,
+							  StateData#state.resource,
+							  Info);
+			 _ ->
+			    ok
+		       end,
 		       handle_unacked_stanzas(StateData)
 		 end,
 		 bounce_messages();
@@ -2726,6 +2743,8 @@ handle_resume(StateData, Attrs) ->
 			  case inherit_session_state(StateData, PrevID) of
 			    {ok, InheritedState} ->
 				{ok, InheritedState, H};
+			    {error, Err, InH} ->
+				{error, ?MGMT_ITEM_NOT_FOUND_H(Xmlns, InH), Err};
 			    {error, Err} ->
 				{error, ?MGMT_ITEM_NOT_FOUND(Xmlns), Err}
 			  end;
@@ -2965,7 +2984,17 @@ inherit_session_state(#state{user = U, server = S} = StateData, ResumeID) ->
       {term, {R, Time}} ->
 	  case ejabberd_sm:get_session_pid(U, S, R) of
 	    none ->
-		{error, <<"Previous session PID not found">>};
+		case ejabberd_sm:get_offline_info(Time, U, S, R) of
+		  none ->
+		      {error, <<"Previous session PID not found">>};
+		  Info ->
+		      case proplists:get_value(num_stanzas_in, Info) of
+			undefined ->
+			    {error, <<"Previous session timed out">>};
+			H ->
+			    {error, <<"Previous session timed out">>, H}
+		      end
+		end;
 	    OldPID ->
 		OldSID = {Time, OldPID},
 		case catch resume_session(OldSID) of

src/ejabberd_sm.erl

@@ -47,6 +47,8 @@
 	 set_presence/7,
 	 unset_presence/6,
 	 close_session_unset_presence/5,
+	 set_offline_info/5,
+	 get_offline_info/4,
 	 dirty_get_sessions_list/0,
 	 dirty_get_my_sessions_list/0,
 	 get_vh_session_list/1,
@@ -178,14 +180,14 @@ get_user_resources(User, Server) ->
     LUser = jid:nodeprep(User),
     LServer = jid:nameprep(Server),
     Mod = get_sm_backend(LServer),
-    Ss = Mod:get_sessions(LUser, LServer),
+    Ss = online(Mod:get_sessions(LUser, LServer)),
     [element(3, S#session.usr) || S <- clean_session_list(Ss)].
 
 -spec get_user_present_resources(binary(), binary()) -> [tuple()].
 
 get_user_present_resources(LUser, LServer) ->
     Mod = get_sm_backend(LServer),
-    Ss = Mod:get_sessions(LUser, LServer),
+    Ss = online(Mod:get_sessions(LUser, LServer)),
     [{S#session.priority, element(3, S#session.usr)}
      || S <- clean_session_list(Ss), is_integer(S#session.priority)].
 
@@ -196,7 +198,7 @@ get_user_ip(User, Server, Resource) ->
     LServer = jid:nameprep(Server),
     LResource = jid:resourceprep(Resource),
     Mod = get_sm_backend(LServer),
-    case Mod:get_sessions(LUser, LServer, LResource) of
+    case online(Mod:get_sessions(LUser, LServer, LResource)) of
 	[] ->
 	    undefined;
 	Ss ->
@@ -211,7 +213,7 @@ get_user_info(User, Server, Resource) ->
     LServer = jid:nameprep(Server),
     LResource = jid:resourceprep(Resource),
     Mod = get_sm_backend(LServer),
-    case Mod:get_sessions(LUser, LServer, LResource) of
+    case online(Mod:get_sessions(LUser, LServer, LResource)) of
 	[] ->
 	    offline;
 	Ss ->
@@ -261,17 +263,42 @@ get_session_pid(User, Server, Resource) ->
     LServer = jid:nameprep(Server),
     LResource = jid:resourceprep(Resource),
     Mod = get_sm_backend(LServer),
-    case Mod:get_sessions(LUser, LServer, LResource) of
+    case online(Mod:get_sessions(LUser, LServer, LResource)) of
 	[#session{sid = {_, Pid}}] -> Pid;
 	_ -> none
     end.
 
+-spec set_offline_info(sid(), binary(), binary(), binary(), info()) -> ok.
+
+set_offline_info({Time, _Pid}, User, Server, Resource, Info) ->
+    SID = {Time, undefined},
+    LUser = jid:nodeprep(User),
+    LServer = jid:nameprep(Server),
+    LResource = jid:resourceprep(Resource),
+    set_session(SID, LUser, LServer, LResource, undefined, Info).
+
+-spec get_offline_info(erlang:timestamp(), binary(), binary(),
+                       binary()) -> none | info().
+
+get_offline_info(Time, User, Server, Resource) ->
+    SID = {Time, undefined},
+    LUser = jid:nodeprep(User),
+    LServer = jid:nameprep(Server),
+    LResource = jid:resourceprep(Resource),
+    Mod = get_sm_backend(LServer),
+    case Mod:get_sessions(LUser, LServer, LResource) of
+	[#session{sid = SID, info = Info}] ->
+	    Info;
+	_ ->
+	    none
+    end.
+
 -spec dirty_get_sessions_list() -> [ljid()].
 
 dirty_get_sessions_list() ->
     lists:flatmap(
       fun(Mod) ->
-	      [S#session.usr || S <- Mod:get_sessions()]
+	      [S#session.usr || S <- online(Mod:get_sessions())]
       end, get_sm_backends()).
 
 -spec dirty_get_my_sessions_list() -> [#session{}].
@@ -279,7 +306,7 @@ dirty_get_sessions_list() ->
 dirty_get_my_sessions_list() ->
     lists:flatmap(
       fun(Mod) ->
-	      [S || S <- Mod:get_sessions(),
+	      [S || S <- online(Mod:get_sessions()),
 		    node(element(2, S#session.sid)) == node()]
       end, get_sm_backends()).
 
@@ -288,14 +315,14 @@ dirty_get_my_sessions_list() ->
 get_vh_session_list(Server) ->
     LServer = jid:nameprep(Server),
     Mod = get_sm_backend(LServer),
-    [S#session.usr || S <- Mod:get_sessions(LServer)].
+    [S#session.usr || S <- online(Mod:get_sessions(LServer))].
 
 -spec get_all_pids() -> [pid()].
 
 get_all_pids() ->
     lists:flatmap(
       fun(Mod) ->
-	      [element(2, S#session.sid) || S <- Mod:get_sessions()]
+	      [element(2, S#session.sid) || S <- online(Mod:get_sessions())]
       end, get_sm_backends()).
 
 -spec get_vh_session_number(binary()) -> non_neg_integer().
@@ -303,7 +330,7 @@ get_all_pids() ->
 get_vh_session_number(Server) ->
     LServer = jid:nameprep(Server),
     Mod = get_sm_backend(LServer),
-    length(Mod:get_sessions(LServer)).
+    length(online(Mod:get_sessions(LServer))).
 
 register_iq_handler(Host, XMLNS, Module, Fun) ->
     ejabberd_sm ! {register_iq_handler, Host, XMLNS, Module, Fun}.
@@ -395,6 +422,15 @@ set_session(SID, User, Server, Resource, Priority, Info) ->
     Mod:set_session(#session{sid = SID, usr = USR, us = US,
 			     priority = Priority, info = Info}).
 
+-spec online([#session{}]) -> [#session{}].
+
+online(Sessions) ->
+    lists:filter(fun(#session{sid = {_, undefined}}) ->
+			 false;
+		    (_) ->
+			 true
+		 end, Sessions).
+
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 do_route(From, To, {broadcast, _} = Packet) ->
@@ -409,7 +445,7 @@ do_route(From, To, {broadcast, _} = Packet) ->
         _ ->
             {U, S, R} = jid:tolower(To),
 	    Mod = get_sm_backend(S),
-	    case Mod:get_sessions(U, S, R) of
+	    case online(Mod:get_sessions(U, S, R)) of
                 [] ->
                     ?DEBUG("packet dropped~n", []);
                 Ss ->
@@ -511,8 +547,8 @@ do_route(From, To, #xmlel{} = Packet) ->
 	    _ -> ok
 	  end;
       _ ->
-	  Mod = get_sm_backend(LServer),
-	  case Mod:get_sessions(LUser, LServer, LResource) of
+	Mod = get_sm_backend(LServer),
+	case online(Mod:get_sessions(LUser, LServer, LResource)) of
 	    [] ->
 		case Name of
 		  <<"message">> ->
@@ -584,8 +620,8 @@ route_message(From, To, Packet, Type) ->
 					  (P >= 0) and (Type == headline) ->
 				LResource = jid:resourceprep(R),
 				Mod = get_sm_backend(LServer),
-				case Mod:get_sessions(LUser, LServer,
-						      LResource) of
+				case online(Mod:get_sessions(LUser, LServer,
+							     LResource)) of
 				  [] ->
 				      ok; % Race condition
 				  Ss ->
@@ -646,7 +682,11 @@ check_existing_resources(LUser, LServer, LResource) ->
     if SIDs == [] -> ok;
        true ->
 	   MaxSID = lists:max(SIDs),
-	   lists:foreach(fun ({_, Pid} = S) when S /= MaxSID ->
+	   lists:foreach(fun ({_, undefined} = S) ->
+				 Mod = get_sm_backend(LServer),
+				 Mod:delete_session(LUser, LServer, LResource,
+						    S);
+			     ({_, Pid} = S) when S /= MaxSID ->
 				 Pid ! replaced;
 			     (_) -> ok
 			 end,
@@ -663,11 +703,11 @@ get_resource_sessions(User, Server, Resource) ->
     LServer = jid:nameprep(Server),
     LResource = jid:resourceprep(Resource),
     Mod = get_sm_backend(LServer),
-    [S#session.sid || S <- Mod:get_sessions(LUser, LServer, LResource)].
+    [S#session.sid || S <- online(Mod:get_sessions(LUser, LServer, LResource))].
 
 check_max_sessions(LUser, LServer) ->
     Mod = get_sm_backend(LServer),
-    SIDs = [S#session.sid || S <- Mod:get_sessions(LUser, LServer)],
+    SIDs = [S#session.sid || S <- online(Mod:get_sessions(LUser, LServer))],
     MaxSessions = get_max_user_sessions(LUser, LServer),
     if length(SIDs) =< MaxSessions -> ok;
        true -> {_, Pid} = lists:min(SIDs), Pid ! replaced
@@ -721,7 +761,7 @@ process_iq(From, To, Packet) ->
 
 force_update_presence({LUser, LServer}) ->
     Mod = get_sm_backend(LServer),
-    Ss = Mod:get_sessions(LUser, LServer),
+    Ss = online(Mod:get_sessions(LUser, LServer)),
     lists:foreach(fun (#session{sid = {_, Pid}}) ->
 			  Pid ! {force_update_presence, LUser, LServer}
 		  end,

test/ejabberd_SUITE.erl

@@ -203,6 +203,8 @@ init_per_testcase(TestCase, OrigConfig) ->
             auth(connect(Config));
 	sm_resume ->
 	    auth(connect(Config));
+	sm_resume_failed ->
+	    auth(connect(Config));
         test_open_session ->
             bind(auth(connect(Config)));
         _ when IsMaster or IsSlave ->
@@ -231,6 +233,7 @@ no_db_tests() ->
        stats,
        sm,
        sm_resume,
+       sm_resume_failed,
        disco]},
      {test_proxy65, [parallel],
       [proxy65_master, proxy65_slave]}].
@@ -641,6 +644,17 @@ sm_resume(Config) ->
     ?recv1(#message{from = ServerJID, to = MyJID, body = [Txt]}),
     ?recv1(#sm_r{}),
     send(Config, #sm_a{h = 1, xmlns = ?NS_STREAM_MGMT_3}),
+    %% Send another stanza to increment the server's 'h' for sm_resume_failed.
+    send(Config, #presence{to = ServerJID}),
+    close_socket(Config),
+    {save_config, set_opt(sm_previd, ID, Config)}.
+
+sm_resume_failed(Config) ->
+    {sm_resume, SMConfig} = ?config(saved_config, Config),
+    ID = ?config(sm_previd, SMConfig),
+    ct:sleep(5000), % Wait for session to time out.
+    send(Config, #sm_resume{previd = ID, h = 1, xmlns = ?NS_STREAM_MGMT_3}),
+    ?recv1(#sm_failed{reason = 'item-not-found', h = 4}),
     disconnect(Config).
 
 private(Config) ->

test/ejabberd_SUITE_data/ejabberd.yml

@@ -419,6 +419,7 @@ listen:
     starttls: true
     shaper: c2s_shaper
     access: c2s
+    resume_timeout: 3
   - 
     port: @@s2s_port@@
     module: ejabberd_s2s_in

tools/xmpp_codec.erl

@@ -2174,7 +2174,7 @@ encode({sm_resumed, _, _, _} = Resumed) ->
     encode_sm_resumed(Resumed, []);
 encode({sm_r, _} = R) -> encode_sm_r(R, []);
 encode({sm_a, _, _} = A) -> encode_sm_a(A, []);
-encode({sm_failed, _, _} = Failed) ->
+encode({sm_failed, _, _, _} = Failed) ->
     encode_sm_failed(Failed, []);
 encode({offline_item, _, _} = Item) ->
     encode_offline_item(Item,
@@ -2597,7 +2597,7 @@ pp(sm_resume, 3) -> [h, previd, xmlns];
 pp(sm_resumed, 3) -> [h, previd, xmlns];
 pp(sm_r, 1) -> [xmlns];
 pp(sm_a, 2) -> [h, xmlns];
-pp(sm_failed, 2) -> [reason, xmlns];
+pp(sm_failed, 3) -> [reason, h, xmlns];
 pp(offline_item, 2) -> [node, action];
 pp(offline, 3) -> [items, purge, fetch];
 pp(mix_join, 2) -> [jid, subscribe];
@@ -2963,9 +2963,9 @@ decode_sm_failed(__TopXMLNS, __IgnoreEls,
 		 {xmlel, <<"failed">>, _attrs, _els}) ->
     Reason = decode_sm_failed_els(__TopXMLNS, __IgnoreEls,
 				  _els, undefined),
-    Xmlns = decode_sm_failed_attrs(__TopXMLNS, _attrs,
-				   undefined),
-    {sm_failed, Reason, Xmlns}.
+    {H, Xmlns} = decode_sm_failed_attrs(__TopXMLNS, _attrs,
+					undefined, undefined),
+    {sm_failed, Reason, H, Xmlns}.
 
 decode_sm_failed_els(__TopXMLNS, __IgnoreEls, [],
 		     Reason) ->
@@ -3285,20 +3285,25 @@ decode_sm_failed_els(__TopXMLNS, __IgnoreEls,
 			 Reason).
 
 decode_sm_failed_attrs(__TopXMLNS,
-		       [{<<"xmlns">>, _val} | _attrs], _Xmlns) ->
-    decode_sm_failed_attrs(__TopXMLNS, _attrs, _val);
-decode_sm_failed_attrs(__TopXMLNS, [_ | _attrs],
+		       [{<<"h">>, _val} | _attrs], _H, Xmlns) ->
+    decode_sm_failed_attrs(__TopXMLNS, _attrs, _val, Xmlns);
+decode_sm_failed_attrs(__TopXMLNS,
+		       [{<<"xmlns">>, _val} | _attrs], H, _Xmlns) ->
+    decode_sm_failed_attrs(__TopXMLNS, _attrs, H, _val);
+decode_sm_failed_attrs(__TopXMLNS, [_ | _attrs], H,
 		       Xmlns) ->
-    decode_sm_failed_attrs(__TopXMLNS, _attrs, Xmlns);
-decode_sm_failed_attrs(__TopXMLNS, [], Xmlns) ->
-    decode_sm_failed_attr_xmlns(__TopXMLNS, Xmlns).
+    decode_sm_failed_attrs(__TopXMLNS, _attrs, H, Xmlns);
+decode_sm_failed_attrs(__TopXMLNS, [], H, Xmlns) ->
+    {decode_sm_failed_attr_h(__TopXMLNS, H),
+     decode_sm_failed_attr_xmlns(__TopXMLNS, Xmlns)}.
 
-encode_sm_failed({sm_failed, Reason, Xmlns},
+encode_sm_failed({sm_failed, Reason, H, Xmlns},
 		 _xmlns_attrs) ->
     _els = lists:reverse('encode_sm_failed_$reason'(Reason,
 						    [])),
     _attrs = encode_sm_failed_attr_xmlns(Xmlns,
-					 _xmlns_attrs),
+					 encode_sm_failed_attr_h(H,
+								 _xmlns_attrs)),
     {xmlel, <<"failed">>, _attrs, _els}.
 
 'encode_sm_failed_$reason'(undefined, _acc) -> _acc;
@@ -3443,6 +3448,20 @@ encode_sm_failed({sm_failed, Reason, Xmlns},
 				       <<"urn:ietf:params:xml:ns:xmpp-stanzas">>}])
      | _acc].
 
+decode_sm_failed_attr_h(__TopXMLNS, undefined) ->
+    undefined;
+decode_sm_failed_attr_h(__TopXMLNS, _val) ->
+    case catch dec_int(_val, 0, infinity) of
+      {'EXIT', _} ->
+	  erlang:error({xmpp_codec,
+			{bad_attr_value, <<"h">>, <<"failed">>, __TopXMLNS}});
+      _res -> _res
+    end.
+
+encode_sm_failed_attr_h(undefined, _acc) -> _acc;
+encode_sm_failed_attr_h(_val, _acc) ->
+    [{<<"h">>, enc_int(_val)} | _acc].
+
 decode_sm_failed_attr_xmlns(__TopXMLNS, undefined) ->
     undefined;
 decode_sm_failed_attr_xmlns(__TopXMLNS, _val) -> _val.

tools/xmpp_codec.hrl

@@ -440,6 +440,7 @@
 -record(sasl_mechanisms, {list = [] :: [binary()]}).
 
 -record(sm_failed, {reason :: atom() | #gone{} | #redirect{},
+                    h :: non_neg_integer(),
                     xmlns :: binary()}).
 
 -record(error, {type :: 'auth' | 'cancel' | 'continue' | 'modify' | 'wait',

tools/xmpp_codec.spec

@@ -2351,8 +2351,11 @@
 -xml(sm_failed,
      #elem{name = <<"failed">>,
 	   xmlns = [<<"urn:xmpp:sm:2">>, <<"urn:xmpp:sm:3">>],
-	   result = {sm_failed, '$reason', '$xmlns'},
-	   attrs = [#attr{name = <<"xmlns">>}],
+	   result = {sm_failed, '$reason', '$h', '$xmlns'},
+	   attrs = [#attr{name = <<"h">>,
+			  dec = {dec_int, [0, infinity]},
+			  enc = {enc_int, []}},
+		    #attr{name = <<"xmlns">>}],
 	   refs = [#ref{name = error_bad_request,
                         min = 0, max = 1, label = '$reason'},
                    #ref{name = error_conflict,