yuanbiao
/
emqx
1
0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

fix(emqx_sn): race_condition when discarding

This commit is contained in:
Shawn 2021-04-16 11:43:13 +08:00 committed by turtleDeng
parent 4885171e4f
commit 98edbc39af
2 changed files with 43 additions and 48 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

51
apps/emqx_sn/src/emqx_sn_gateway.erl
View File

@ -202,7 +202,7 @@ idle(cast, {incoming, ?SN_PUBLISH_MSG(#mqtt_sn_flags{qos = ?QOS_NEG1,
}, TopicId, _MsgId, Data)}, }, TopicId, _MsgId, Data)},
State = #state{clientid = ClientId, registry = Registry}) -> State = #state{clientid = ClientId, registry = Registry}) ->
TopicName = case (TopicIdType =:= ?SN_SHORT_TOPIC) of TopicName = case (TopicIdType =:= ?SN_SHORT_TOPIC) of
false -> emqx_sn_registry:lookup_topic(Registry, ClientId, TopicId); false -> emqx_sn_registry:lookup_topic(Registry, self(), TopicId);
true -> <<TopicId:16>> true -> <<TopicId:16>>
end, end,
_ = case TopicName =/= undefined of _ = case TopicName =/= undefined of
@ -294,7 +294,7 @@ wait_for_will_msg(EventType, EventContent, State) ->
connected(cast, {incoming, ?SN_REGISTER_MSG(_TopicId, MsgId, TopicName)}, connected(cast, {incoming, ?SN_REGISTER_MSG(_TopicId, MsgId, TopicName)},
State = #state{clientid = ClientId, registry = Registry}) -> State = #state{clientid = ClientId, registry = Registry}) ->
case emqx_sn_registry:register_topic(Registry, ClientId, TopicName) of case emqx_sn_registry:register_topic(Registry, self(), TopicName) of
TopicId when is_integer(TopicId) -> TopicId when is_integer(TopicId) ->
?LOG(debug, "register ClientId=~p, TopicName=~p, TopicId=~p", [ClientId, TopicName, TopicId]), ?LOG(debug, "register ClientId=~p, TopicName=~p, TopicId=~p", [ClientId, TopicName, TopicId]),
send_message(?SN_REGACK_MSG(TopicId, MsgId, ?SN_RC_ACCEPTED), State); send_message(?SN_REGACK_MSG(TopicId, MsgId, ?SN_RC_ACCEPTED), State);
@ -586,10 +586,9 @@ handle_event(EventType, EventContent, StateName, State) ->
[StateName, {EventType, EventContent}]), [StateName, {EventType, EventContent}]),
{keep_state, State}. {keep_state, State}.
terminate(Reason, _StateName, #state{clientid = ClientId, terminate(Reason, _StateName, #state{channel = Channel,
channel = Channel,
registry = Registry}) -> registry = Registry}) ->
emqx_sn_registry:unregister_topic(Registry, ClientId), emqx_sn_registry:unregister_topic(Registry, self()),
case Channel =:= undefined of case Channel =:= undefined of
true -> ok; true -> ok;
false -> emqx_channel:terminate(Reason, Channel) false -> emqx_channel:terminate(Reason, Channel)
@ -724,12 +723,10 @@ mqtt2sn(?UNSUBACK_PACKET(MsgId), _State)->
?SN_UNSUBACK_MSG(MsgId); ?SN_UNSUBACK_MSG(MsgId);
mqtt2sn(?PUBLISH_PACKET(QoS, Topic, PacketId, Payload), #state{registry = Registry}) -> mqtt2sn(?PUBLISH_PACKET(QoS, Topic, PacketId, Payload), #state{registry = Registry}) ->
NewPacketId = if NewPacketId = if QoS =:= ?QOS_0 -> 0;
QoS =:= ?QOS_0 -> 0; true -> PacketId
true -> PacketId
end, end,
ClientId = get(clientid), {TopicIdType, TopicContent} = case emqx_sn_registry:lookup_topic_id(Registry, self(), Topic) of
{TopicIdType, TopicContent} = case emqx_sn_registry:lookup_topic_id(Registry, ClientId, Topic) of
{predef, PredefTopicId} -> {predef, PredefTopicId} ->
{?SN_PREDEFINED_TOPIC, PredefTopicId}; {?SN_PREDEFINED_TOPIC, PredefTopicId};
TopicId when is_integer(TopicId) -> TopicId when is_integer(TopicId) ->
@ -830,7 +827,6 @@ do_connect(ClientId, CleanStart, WillFlag, Duration, State) ->
keepalive = Duration, keepalive = Duration,
properties = OnlyOneInflight properties = OnlyOneInflight
}, },
put(clientid, ClientId),
case WillFlag of case WillFlag of
true -> send_message(?SN_WILLTOPICREQ_MSG(), State), true -> send_message(?SN_WILLTOPICREQ_MSG(), State),
NState = State#state{connpkt = ConnPkt, NState = State#state{connpkt = ConnPkt,
@ -847,7 +843,6 @@ do_connect(ClientId, CleanStart, WillFlag, Duration, State) ->
do_2nd_connect(Flags, Duration, ClientId, State = #state{sockname = Sockname, do_2nd_connect(Flags, Duration, ClientId, State = #state{sockname = Sockname,
peername = Peername, peername = Peername,
clientid = OldClientId,
registry = Registry, registry = Registry,
channel = Channel}) -> channel = Channel}) ->
emqx_logger:set_metadata_clientid(ClientId), emqx_logger:set_metadata_clientid(ClientId),
@ -855,7 +850,7 @@ do_2nd_connect(Flags, Duration, ClientId, State = #state{sockname = Sockname,
NChannel = case CleanStart of NChannel = case CleanStart of
true -> true ->
emqx_channel:terminate(normal, Channel), emqx_channel:terminate(normal, Channel),
emqx_sn_registry:unregister_topic(Registry, OldClientId), emqx_sn_registry:unregister_topic(Registry, self()),
emqx_channel:init(#{socktype => udp, emqx_channel:init(#{socktype => udp,
sockname => Sockname, sockname => Sockname,
peername => Peername, peername => Peername,
@ -868,8 +863,8 @@ do_2nd_connect(Flags, Duration, ClientId, State = #state{sockname = Sockname,
do_connect(ClientId, CleanStart, Will, Duration, NState). do_connect(ClientId, CleanStart, Will, Duration, NState).
handle_subscribe(?SN_NORMAL_TOPIC, TopicName, QoS, MsgId, handle_subscribe(?SN_NORMAL_TOPIC, TopicName, QoS, MsgId,
State=#state{clientid = ClientId, registry = Registry}) -> State=#state{registry = Registry}) ->
case emqx_sn_registry:register_topic(Registry, ClientId, TopicName) of case emqx_sn_registry:register_topic(Registry, self(), TopicName) of
{error, too_large} -> {error, too_large} ->
ok = send_message(?SN_SUBACK_MSG(#mqtt_sn_flags{qos = QoS}, ok = send_message(?SN_SUBACK_MSG(#mqtt_sn_flags{qos = QoS},
?SN_INVALID_TOPIC_ID, ?SN_INVALID_TOPIC_ID,
@ -883,8 +878,8 @@ handle_subscribe(?SN_NORMAL_TOPIC, TopicName, QoS, MsgId,
end; end;
handle_subscribe(?SN_PREDEFINED_TOPIC, TopicId, QoS, MsgId, handle_subscribe(?SN_PREDEFINED_TOPIC, TopicId, QoS, MsgId,
State = #state{clientid = ClientId, registry = Registry}) -> State = #state{registry = Registry}) ->
case emqx_sn_registry:lookup_topic(Registry, ClientId, TopicId) of case emqx_sn_registry:lookup_topic(Registry, self(), TopicId) of
undefined -> undefined ->
ok = send_message(?SN_SUBACK_MSG(#mqtt_sn_flags{qos = QoS}, ok = send_message(?SN_SUBACK_MSG(#mqtt_sn_flags{qos = QoS},
TopicId, TopicId,
@ -913,8 +908,8 @@ handle_unsubscribe(?SN_NORMAL_TOPIC, TopicId, MsgId, State) ->
proto_unsubscribe(TopicId, MsgId, State); proto_unsubscribe(TopicId, MsgId, State);
handle_unsubscribe(?SN_PREDEFINED_TOPIC, TopicId, MsgId, handle_unsubscribe(?SN_PREDEFINED_TOPIC, TopicId, MsgId,
State = #state{clientid = ClientId, registry = Registry}) -> State = #state{registry = Registry}) ->
case emqx_sn_registry:lookup_topic(Registry, ClientId, TopicId) of case emqx_sn_registry:lookup_topic(Registry, self(), TopicId) of
undefined -> undefined ->
ok = send_message(?SN_UNSUBACK_MSG(MsgId), State), ok = send_message(?SN_UNSUBACK_MSG(MsgId), State),
{keep_state, State}; {keep_state, State};
@ -938,10 +933,10 @@ do_publish(?SN_NORMAL_TOPIC, TopicName, Data, Flags, MsgId, State) ->
<<TopicId:16>> = TopicName, <<TopicId:16>> = TopicName,
do_publish(?SN_PREDEFINED_TOPIC, TopicId, Data, Flags, MsgId, State); do_publish(?SN_PREDEFINED_TOPIC, TopicId, Data, Flags, MsgId, State);
do_publish(?SN_PREDEFINED_TOPIC, TopicId, Data, Flags, MsgId, do_publish(?SN_PREDEFINED_TOPIC, TopicId, Data, Flags, MsgId,
State=#state{clientid = ClientId, registry = Registry}) -> State=#state{registry = Registry}) ->
#mqtt_sn_flags{qos = QoS, dup = Dup, retain = Retain} = Flags, #mqtt_sn_flags{qos = QoS, dup = Dup, retain = Retain} = Flags,
NewQoS = get_corrected_qos(QoS), NewQoS = get_corrected_qos(QoS),
case emqx_sn_registry:lookup_topic(Registry, ClientId, TopicId) of case emqx_sn_registry:lookup_topic(Registry, self(), TopicId) of
undefined -> undefined ->
(NewQoS =/= ?QOS_0) andalso send_message(?SN_PUBACK_MSG(TopicId, MsgId, ?SN_RC_INVALID_TOPIC_ID), State), (NewQoS =/= ?QOS_0) andalso send_message(?SN_PUBACK_MSG(TopicId, MsgId, ?SN_RC_INVALID_TOPIC_ID), State),
{keep_state, State}; {keep_state, State};
@ -979,12 +974,12 @@ do_publish_will(#state{will_msg = WillMsg, clientid = ClientId}) ->
ok. ok.
do_puback(TopicId, MsgId, ReturnCode, StateName, do_puback(TopicId, MsgId, ReturnCode, StateName,
State=#state{clientid = ClientId, registry = Registry}) -> State=#state{registry = Registry}) ->
case ReturnCode of case ReturnCode of
?SN_RC_ACCEPTED -> ?SN_RC_ACCEPTED ->
handle_incoming(?PUBACK_PACKET(MsgId), StateName, State); handle_incoming(?PUBACK_PACKET(MsgId), StateName, State);
?SN_RC_INVALID_TOPIC_ID -> ?SN_RC_INVALID_TOPIC_ID ->
case emqx_sn_registry:lookup_topic(Registry, ClientId, TopicId) of case emqx_sn_registry:lookup_topic(Registry, self(), TopicId) of
undefined -> ok; undefined -> ok;
TopicName -> TopicName ->
%%notice that this TopicName maybe normal or predefined, %%notice that this TopicName maybe normal or predefined,
@ -1072,24 +1067,24 @@ handle_outgoing(Packets, State) when is_list(Packets) ->
lists:foreach(fun(Packet) -> handle_outgoing(Packet, State) end, Packets); lists:foreach(fun(Packet) -> handle_outgoing(Packet, State) end, Packets);
handle_outgoing(PubPkt = ?PUBLISH_PACKET(QoS, TopicName, PacketId, Payload), handle_outgoing(PubPkt = ?PUBLISH_PACKET(QoS, TopicName, PacketId, Payload),
State = #state{clientid = ClientId, registry = Registry}) -> State = #state{registry = Registry}) ->
#mqtt_packet{header = #mqtt_packet_header{dup = Dup, retain = Retain}} = PubPkt, #mqtt_packet{header = #mqtt_packet_header{dup = Dup, retain = Retain}} = PubPkt,
MsgId = message_id(PacketId), MsgId = message_id(PacketId),
?LOG(debug, "Handle outgoing: ~0p", [PubPkt]), ?LOG(debug, "Handle outgoing: ~0p", [PubPkt]),
(emqx_sn_registry:lookup_topic_id(Registry, ClientId, TopicName) == undefined) (emqx_sn_registry:lookup_topic_id(Registry, self(), TopicName) == undefined)
andalso (byte_size(TopicName) =/= 2) andalso (byte_size(TopicName) =/= 2)
andalso register_and_notify_client(TopicName, Payload, Dup, QoS, andalso register_and_notify_client(TopicName, Payload, Dup, QoS,
Retain, MsgId, ClientId, State), Retain, MsgId, State),
send_message(mqtt2sn(PubPkt, State), State); send_message(mqtt2sn(PubPkt, State), State);
handle_outgoing(Packet, State) -> handle_outgoing(Packet, State) ->
send_message(mqtt2sn(Packet, State), State). send_message(mqtt2sn(Packet, State), State).
register_and_notify_client(TopicName, Payload, Dup, QoS, Retain, MsgId, ClientId, register_and_notify_client(TopicName, Payload, Dup, QoS, Retain, MsgId,
State = #state{registry = Registry}) -> State = #state{registry = Registry}) ->
TopicId = emqx_sn_registry:register_topic(Registry, ClientId, TopicName), TopicId = emqx_sn_registry:register_topic(Registry, self(), TopicName),
?LOG(debug, "Register TopicId=~p, TopicName=~p, Payload=~p, Dup=~p, QoS=~p, " ?LOG(debug, "Register TopicId=~p, TopicName=~p, Payload=~p, Dup=~p, QoS=~p, "
"Retain=~p, MsgId=~p", [TopicId, TopicName, Payload, Dup, QoS, Retain, MsgId]), "Retain=~p, MsgId=~p", [TopicId, TopicName, Payload, Dup, QoS, Retain, MsgId]),
send_register(TopicName, TopicId, MsgId, State). send_register(TopicName, TopicId, MsgId, State).

40
apps/emqx_sn/src/emqx_sn_registry.erl
View File

@ -61,10 +61,10 @@ stop({_Tab, Pid}) ->
gen_server:stop(Pid, normal, infinity). gen_server:stop(Pid, normal, infinity).
-spec(register_topic(registry(), binary(), binary()) -> integer() | {error, term()}). -spec(register_topic(registry(), binary(), binary()) -> integer() | {error, term()}).
register_topic({_, Pid}, ClientId, TopicName) when is_binary(TopicName) -> register_topic({_, Pid}, ClientPid, TopicName) when is_binary(TopicName) ->
case emqx_topic:wildcard(TopicName) of case emqx_topic:wildcard(TopicName) of
false -> false ->
gen_server:call(Pid, {register, ClientId, TopicName}); gen_server:call(Pid, {register, ClientPid, TopicName});
%% TopicId: in case of “accepted” the value that will be used as topic %% TopicId: in case of “accepted” the value that will be used as topic
%% id by the gateway when sending PUBLISH messages to the client (not %% id by the gateway when sending PUBLISH messages to the client (not
%% relevant in case of subscriptions to a short topic name or to a topic %% relevant in case of subscriptions to a short topic name or to a topic
@ -73,10 +73,10 @@ register_topic({_, Pid}, ClientId, TopicName) when is_binary(TopicName) ->
end. end.
-spec(lookup_topic(registry(), binary(), pos_integer()) -> undefined | binary()). -spec(lookup_topic(registry(), binary(), pos_integer()) -> undefined | binary()).
lookup_topic({Tab, _Pid}, ClientId, TopicId) when is_integer(TopicId) -> lookup_topic({Tab, _Pid}, ClientPid, TopicId) when is_integer(TopicId) ->
case lookup_element(Tab, {predef, TopicId}, 2) of case lookup_element(Tab, {predef, TopicId}, 2) of
undefined -> undefined ->
lookup_element(Tab, {ClientId, TopicId}, 2); lookup_element(Tab, {ClientPid, TopicId}, 2);
Topic -> Topic Topic -> Topic
end. end.
@ -84,10 +84,10 @@ lookup_topic({Tab, _Pid}, ClientId, TopicId) when is_integer(TopicId) ->
-> undefined -> undefined
| pos_integer() | pos_integer()
| {predef, integer()}). | {predef, integer()}).
lookup_topic_id({Tab, _Pid}, ClientId, TopicName) when is_binary(TopicName) -> lookup_topic_id({Tab, _Pid}, ClientPid, TopicName) when is_binary(TopicName) ->
case lookup_element(Tab, {predef, TopicName}, 2) of case lookup_element(Tab, {predef, TopicName}, 2) of
undefined -> undefined ->
lookup_element(Tab, {ClientId, TopicName}, 2); lookup_element(Tab, {ClientPid, TopicName}, 2);
TopicId -> TopicId ->
{predef, TopicId} {predef, TopicId}
end. end.
@ -97,16 +97,16 @@ lookup_element(Tab, Key, Pos) ->
try ets:lookup_element(Tab, Key, Pos) catch error:badarg -> undefined end. try ets:lookup_element(Tab, Key, Pos) catch error:badarg -> undefined end.
-spec(unregister_topic(registry(), binary()) -> ok). -spec(unregister_topic(registry(), binary()) -> ok).
unregister_topic({_Tab, Pid}, ClientId) -> unregister_topic({_Tab, Pid}, ClientPid) ->
gen_server:call(Pid, {unregister, ClientId}). gen_server:call(Pid, {unregister, ClientPid}).
%%----------------------------------------------------------------------------- %%-----------------------------------------------------------------------------
init([Tab, PredefTopics]) -> init([Tab, PredefTopics]) ->
%% {predef, TopicId} -> TopicName %% {predef, TopicId} -> TopicName
%% {predef, TopicName} -> TopicId %% {predef, TopicName} -> TopicId
%% {ClientId, TopicId} -> TopicName %% {ClientPid, TopicId} -> TopicName
%% {ClientId, TopicName} -> TopicId %% {ClientPid, TopicName} -> TopicId
_ = ets:new(Tab, [set, public, named_table, {read_concurrency, true}]), _ = ets:new(Tab, [set, public, named_table, {read_concurrency, true}]),
MaxPredefId = lists:foldl( MaxPredefId = lists:foldl(
fun({TopicId, TopicName}, AccId) -> fun({TopicId, TopicName}, AccId) ->
@ -116,27 +116,27 @@ init([Tab, PredefTopics]) ->
end, 0, PredefTopics), end, 0, PredefTopics),
{ok, #state{tab = Tab, max_predef_topic_id = MaxPredefId}}. {ok, #state{tab = Tab, max_predef_topic_id = MaxPredefId}}.
handle_call({register, ClientId, TopicName}, _From, handle_call({register, ClientPid, TopicName}, _From,
State = #state{tab = Tab, max_predef_topic_id = PredefId}) -> State = #state{tab = Tab, max_predef_topic_id = PredefId}) ->
case lookup_topic_id({Tab, self()}, ClientId, TopicName) of case lookup_topic_id({Tab, self()}, ClientPid, TopicName) of
{predef, PredefTopicId} when is_integer(PredefTopicId) -> {predef, PredefTopicId} when is_integer(PredefTopicId) ->
{reply, PredefTopicId, State}; {reply, PredefTopicId, State};
TopicId when is_integer(TopicId) -> TopicId when is_integer(TopicId) ->
{reply, TopicId, State}; {reply, TopicId, State};
undefined -> undefined ->
case next_topic_id(Tab, PredefId, ClientId) of case next_topic_id(Tab, PredefId, ClientPid) of
TopicId when TopicId >= 16#FFFF -> TopicId when TopicId >= 16#FFFF ->
{reply, {error, too_large}, State}; {reply, {error, too_large}, State};
TopicId -> TopicId ->
_ = ets:insert(Tab, {{ClientId, next_topic_id}, TopicId + 1}), _ = ets:insert(Tab, {{ClientPid, next_topic_id}, TopicId + 1}),
_ = ets:insert(Tab, {{ClientId, TopicName}, TopicId}), _ = ets:insert(Tab, {{ClientPid, TopicName}, TopicId}),
_ = ets:insert(Tab, {{ClientId, TopicId}, TopicName}), _ = ets:insert(Tab, {{ClientPid, TopicId}, TopicName}),
{reply, TopicId, State} {reply, TopicId, State}
end end
end; end;
handle_call({unregister, ClientId}, _From, State = #state{tab = Tab}) -> handle_call({unregister, ClientPid}, _From, State = #state{tab = Tab}) ->
ets:match_delete(Tab, {{ClientId, '_'}, '_'}), ets:match_delete(Tab, {{ClientPid, '_'}, '_'}),
{reply, ok, State}; {reply, ok, State};
handle_call(Req, _From, State) -> handle_call(Req, _From, State) ->
@ -159,8 +159,8 @@ code_change(_OldVsn, State, _Extra) ->
%%----------------------------------------------------------------------------- %%-----------------------------------------------------------------------------
next_topic_id(Tab, PredefId, ClientId) -> next_topic_id(Tab, PredefId, ClientPid) ->
case ets:lookup(Tab, {ClientId, next_topic_id}) of case ets:lookup(Tab, {ClientPid, next_topic_id}) of
[{_, Id}] -> Id; [{_, Id}] -> Id;
[] -> PredefId + 1 [] -> PredefId + 1
end. end.