%%%-------------------------------------------------------------------
%%% Author : Holger Weiss <holger@zedat.fu-berlin.de>
%%% Created : 25 Dec 2016 by Evgeny Khramtsov <ekhramtsov@process-one.net>
%%%
%%%
%%% ejabberd, Copyright (C) 2002-2022 ProcessOne
%%%
%%% This program is free software; you can redistribute it and/or
%%% modify it under the terms of the GNU General Public License as
%%% published by the Free Software Foundation; either version 2 of the
%%% License, or (at your option) any later version.
%%%
%%% This program is distributed in the hope that it will be useful,
%%% but WITHOUT ANY WARRANTY; without even the implied warranty of
%%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
%%% General Public License for more details.
%%%
%%% You should have received a copy of the GNU General Public License along
%%% with this program; if not, write to the Free Software Foundation, Inc.,
%%% 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
%%%
%%%-------------------------------------------------------------------
-module(mod_stream_mgmt).
-behaviour(gen_mod).
-author('holger@zedat.fu-berlin.de').
-protocol({xep, 198, '1.5.2', '14.05', "", ""}).
%% gen_mod API
-export([start/2, stop/1, reload/3, depends/2, mod_opt_type/1, mod_options/1]).
-export([mod_doc/0]).
%% hooks
-export([c2s_stream_started/2, c2s_stream_features/2,
c2s_authenticated_packet/2, c2s_unauthenticated_packet/2,
c2s_unbinded_packet/2, c2s_closed/2, c2s_terminated/2,
c2s_handle_send/3, c2s_handle_info/2, c2s_handle_call/3,
c2s_handle_recv/3]).
%% adjust pending session timeout / access queue
-export([get_resume_timeout/1, set_resume_timeout/2, queue_find/2]).
-include_lib("xmpp/include/xmpp.hrl").
-include("logger.hrl").
-include_lib("p1_utils/include/p1_queue.hrl").
-include("translate.hrl").
-define(STREAM_MGMT_CACHE, stream_mgmt_cache).
-define(is_sm_packet(Pkt),
is_record(Pkt, sm_enable) or
is_record(Pkt, sm_resume) or
is_record(Pkt, sm_a) or
is_record(Pkt, sm_r)).
-type state() :: ejabberd_c2s:state().
-type queue() :: p1_queue:queue({non_neg_integer(), erlang:timestamp(), xmpp_element() | xmlel()}).
-type id() :: binary().
-type error_reason() :: session_not_found | session_timed_out |
session_is_dead | session_has_exited |
session_was_killed | session_copy_timed_out |
invalid_previd.
%%%===================================================================
%%% API
%%%===================================================================
start(Host, Opts) ->
init_cache(Opts),
ejabberd_hooks:add(c2s_stream_started, Host, ?MODULE,
c2s_stream_started, 50),
ejabberd_hooks:add(c2s_post_auth_features, Host, ?MODULE,
c2s_stream_features, 50),
ejabberd_hooks:add(c2s_unauthenticated_packet, Host, ?MODULE,
c2s_unauthenticated_packet, 50),
ejabberd_hooks:add(c2s_unbinded_packet, Host, ?MODULE,
c2s_unbinded_packet, 50),
ejabberd_hooks:add(c2s_authenticated_packet, Host, ?MODULE,
c2s_authenticated_packet, 50),
ejabberd_hooks:add(c2s_handle_send, Host, ?MODULE, c2s_handle_send, 50),
ejabberd_hooks:add(c2s_handle_recv, Host, ?MODULE, c2s_handle_recv, 50),
ejabberd_hooks:add(c2s_handle_info, Host, ?MODULE, c2s_handle_info, 50),
ejabberd_hooks:add(c2s_handle_call, Host, ?MODULE, c2s_handle_call, 50),
ejabberd_hooks:add(c2s_closed, Host, ?MODULE, c2s_closed, 50),
ejabberd_hooks:add(c2s_terminated, Host, ?MODULE, c2s_terminated, 50).
stop(Host) ->
ejabberd_hooks:delete(c2s_stream_started, Host, ?MODULE,
c2s_stream_started, 50),
ejabberd_hooks:delete(c2s_post_auth_features, Host, ?MODULE,
c2s_stream_features, 50),
ejabberd_hooks:delete(c2s_unauthenticated_packet, Host, ?MODULE,
c2s_unauthenticated_packet, 50),
ejabberd_hooks:delete(c2s_unbinded_packet, Host, ?MODULE,
c2s_unbinded_packet, 50),
ejabberd_hooks:delete(c2s_authenticated_packet, Host, ?MODULE,
c2s_authenticated_packet, 50),
ejabberd_hooks:delete(c2s_handle_send, Host, ?MODULE, c2s_handle_send, 50),
ejabberd_hooks:delete(c2s_handle_recv, Host, ?MODULE, c2s_handle_recv, 50),
ejabberd_hooks:delete(c2s_handle_info, Host, ?MODULE, c2s_handle_info, 50),
ejabberd_hooks:delete(c2s_handle_call, Host, ?MODULE, c2s_handle_call, 50),
ejabberd_hooks:delete(c2s_closed, Host, ?MODULE, c2s_closed, 50),
ejabberd_hooks:delete(c2s_terminated, Host, ?MODULE, c2s_terminated, 50).
reload(_Host, NewOpts, _OldOpts) ->
init_cache(NewOpts),
?WARNING_MSG("Module ~ts is reloaded, but new configuration will take "
"effect for newly created client connections only", [?MODULE]).
depends(_Host, _Opts) ->
[].
c2s_stream_started(#{lserver := LServer} = State, _StreamStart) ->
State1 = maps:remove(mgmt_options, State),
ResumeTimeout = get_configured_resume_timeout(LServer),
MaxResumeTimeout = get_max_resume_timeout(LServer, ResumeTimeout),
State1#{mgmt_state => inactive,
mgmt_queue_type => get_queue_type(LServer),
mgmt_max_queue => get_max_ack_queue(LServer),
mgmt_timeout => ResumeTimeout,
mgmt_max_timeout => MaxResumeTimeout,
mgmt_ack_timeout => get_ack_timeout(LServer),
mgmt_resend => get_resend_on_timeout(LServer),
mgmt_stanzas_in => 0,
mgmt_stanzas_out => 0,
mgmt_stanzas_req => 0};
c2s_stream_started(State, _StreamStart) ->
State.
c2s_stream_features(Acc, Host) ->
case gen_mod:is_loaded(Host, ?MODULE) of
true ->
[#feature_sm{xmlns = ?NS_STREAM_MGMT_2},
#feature_sm{xmlns = ?NS_STREAM_MGMT_3}|Acc];
false ->
Acc
end.
c2s_unauthenticated_packet(#{lang := Lang} = State, Pkt) when ?is_sm_packet(Pkt) ->
%% XEP-0198 says: "For client-to-server connections, the client MUST NOT
%% attempt to enable stream management until after it has completed Resource
%% Binding unless it is resuming a previous session". However, it also
%% says: "Stream management errors SHOULD be considered recoverable", so we
%% won't bail out.
Err = #sm_failed{reason = 'not-authorized',
text = xmpp:mk_text(?T("Unauthorized"), Lang),
xmlns = ?NS_STREAM_MGMT_3},
{stop, send(State, Err)};
c2s_unauthenticated_packet(State, _Pkt) ->
State.
c2s_unbinded_packet(State, #sm_resume{} = Pkt) ->
case handle_resume(State, Pkt) of
{ok, ResumedState} ->
{stop, ResumedState};
{error, State1} ->
{stop, State1}
end;
c2s_unbinded_packet(State, Pkt) when ?is_sm_packet(Pkt) ->
c2s_unauthenticated_packet(State, Pkt);
c2s_unbinded_packet(State, _Pkt) ->
State.
c2s_authenticated_packet(#{mgmt_state := MgmtState} = State, Pkt)
when ?is_sm_packet(Pkt) ->
if MgmtState == pending; MgmtState == active ->
{stop, perform_stream_mgmt(Pkt, State)};
true ->
{stop, negotiate_stream_mgmt(Pkt, State)}
end;
c2s_authenticated_packet(State, Pkt) ->
update_num_stanzas_in(State, Pkt).
c2s_handle_recv(#{mgmt_state := MgmtState,
lang := Lang} = State, El, {error, Why}) ->
Xmlns = xmpp:get_ns(El),
IsStanza = xmpp:is_stanza(El),
if Xmlns == ?NS_STREAM_MGMT_2; Xmlns == ?NS_STREAM_MGMT_3 ->
Txt = xmpp:io_format_error(Why),
Err = #sm_failed{reason = 'bad-request',
text = xmpp:mk_text(Txt, Lang),
xmlns = Xmlns},
send(State, Err);
IsStanza andalso (MgmtState == pending orelse MgmtState == active) ->
State1 = update_num_stanzas_in(State, El),
case xmpp:get_type(El) of
<<"result">> -> State1;
<<"error">> -> State1;
_ ->
State1#{mgmt_force_enqueue => true}
end;
true ->
State
end;
c2s_handle_recv(State, _, _) ->
State.
c2s_handle_send(#{mgmt_state := MgmtState, mod := Mod,
lang := Lang} = State, Pkt, SendResult)
when MgmtState == pending; MgmtState == active; MgmtState == resumed ->
IsStanza = xmpp:is_stanza(Pkt),
case Pkt of
_ when IsStanza ->
case need_to_enqueue(State, Pkt) of
{true, State1} ->
case mgmt_queue_add(State1, Pkt) of
#{mgmt_max_queue := exceeded} = State2 ->
State3 = State2#{mgmt_resend => false},
Err = xmpp:serr_policy_violation(
?T("Too many unacked stanzas"), Lang),
send(State3, Err);
State2 when SendResult == ok ->
send_rack(State2);
State2 ->
State2
end;
{false, State1} ->
State1
end;
#stream_error{} ->
case MgmtState of
resumed ->
State;
active ->
State;
pending ->
Mod:stop_async(self()),
{stop, State#{stop_reason => {stream, {out, Pkt}}}}
end;
_ ->
State
end;
c2s_handle_send(State, _Pkt, _Result) ->
State.
c2s_handle_call(#{mgmt_id := MgmtID, mgmt_queue := Queue, mod := Mod} = State,
{resume_session, MgmtID}, From) ->
State1 = State#{mgmt_queue => p1_queue:file_to_ram(Queue)},
Mod:reply(From, {resume, State1}),
{stop, State#{mgmt_state => resumed, mgmt_queue => p1_queue:clear(Queue)}};
c2s_handle_call(#{mod := Mod} = State, {resume_session, _}, From) ->
Mod:reply(From, {error, session_not_found}),
{stop, State};
c2s_handle_call(State, _Call, _From) ->
State.
c2s_handle_info(#{mgmt_ack_timer := TRef, jid := JID, mod := Mod} = State,
{timeout, TRef, ack_timeout}) ->
?DEBUG("Timed out waiting for stream management acknowledgement of ~ts",
[jid:encode(JID)]),
State1 = Mod:close(State),
State2 = State1#{stop_reason => {socket, ack_timeout}},
{stop, transition_to_pending(State2, ack_timeout)};
c2s_handle_info(#{mgmt_state := pending, lang := Lang,
mgmt_pending_timer := TRef, jid := JID, mod := Mod} = State,
{timeout, TRef, pending_timeout}) ->
?DEBUG("Timed out waiting for resumption of stream for ~ts",
[jid:encode(JID)]),
Txt = ?T("Timed out waiting for stream resumption"),
Err = xmpp:serr_connection_timeout(Txt, Lang),
Mod:stop_async(self()),
{stop, State#{mgmt_state => timeout,
stop_reason => {stream, {out, Err}}}};
c2s_handle_info(State, {_Ref, {resume, #{jid := JID} = OldState}}) ->
%% This happens if the resume_session/1 request timed out; the new session
%% now receives the late response.
?DEBUG("Received old session state for ~ts after failed resumption",
[jid:encode(JID)]),
route_unacked_stanzas(OldState#{mgmt_resend => false}),
{stop, State};
c2s_handle_info(State, {timeout, _, Timeout}) when Timeout == ack_timeout;
Timeout == pending_timeout ->
%% Late arrival of an already cancelled timer: we just ignore it.
%% This might happen because misc:cancel_timer/1 doesn't guarantee
%% timer cancellation in the case when p1_server is used.
{stop, State};
c2s_handle_info(State, _) ->
State.
c2s_closed(State, {stream, _}) ->
State;
c2s_closed(#{mgmt_state := active} = State, Reason) ->
{stop, transition_to_pending(State, Reason)};
c2s_closed(State, _Reason) ->
State.
c2s_terminated(#{mgmt_state := resumed, sid := SID, jid := JID} = State, _Reason) ->
?DEBUG("Closing former stream of resumed session for ~ts",
[jid:encode(JID)]),
{U, S, R} = jid:tolower(JID),
ejabberd_sm:close_session(SID, U, S, R),
route_late_queue_after_resume(State),
ejabberd_c2s:bounce_message_queue(SID, JID),
{stop, State};
c2s_terminated(#{mgmt_state := MgmtState, mgmt_stanzas_in := In,
mgmt_id := MgmtID, jid := JID} = State, _Reason) ->
case MgmtState of
timeout ->
store_stanzas_in(jid:tolower(JID), MgmtID, In);
_ ->
ok
end,
route_unacked_stanzas(State),
State;
c2s_terminated(State, _Reason) ->
State.
%%%===================================================================
%%% Adjust pending session timeout / access queue
%%%===================================================================
-spec get_resume_timeout(state()) -> non_neg_integer().
get_resume_timeout(#{mgmt_timeout := Timeout}) ->
Timeout.
-spec set_resume_timeout(state(), non_neg_integer()) -> state().
set_resume_timeout(#{mgmt_timeout := Timeout} = State, Timeout) ->
State;
set_resume_timeout(State, Timeout) ->
State1 = restart_pending_timer(State, Timeout),
State1#{mgmt_timeout => Timeout}.
-spec queue_find(fun((stanza()) -> boolean()), queue())
-> stanza() | none.
queue_find(Pred, Queue) ->
case p1_queue:out(Queue) of
{{value, {_, _, Pkt}}, Queue1} ->
case Pred(Pkt) of
true ->
Pkt;
false ->
queue_find(Pred, Queue1)
end;
{empty, _Queue1} ->
none
end.
%%%===================================================================
%%% Internal functions
%%%===================================================================
-spec negotiate_stream_mgmt(xmpp_element(), state()) -> state().
negotiate_stream_mgmt(Pkt, #{lang := Lang} = State) ->
Xmlns = xmpp:get_ns(Pkt),
case Pkt of
#sm_enable{} ->
handle_enable(State#{mgmt_xmlns => Xmlns}, Pkt);
_ when is_record(Pkt, sm_a);
is_record(Pkt, sm_r);
is_record(Pkt, sm_resume) ->
Txt = ?T("Stream management is not enabled"),
Err = #sm_failed{reason = 'unexpected-request',
text = xmpp:mk_text(Txt, Lang),
xmlns = Xmlns},
send(State, Err)
end.
-spec perform_stream_mgmt(xmpp_element(), state()) -> state().
perform_stream_mgmt(Pkt, #{mgmt_xmlns := Xmlns, lang := Lang} = State) ->
case xmpp:get_ns(Pkt) of
Xmlns ->
case Pkt of
#sm_r{} ->
handle_r(State);
#sm_a{} ->
handle_a(State, Pkt);
_ when is_record(Pkt, sm_enable);
is_record(Pkt, sm_resume) ->
Txt = ?T("Stream management is already enabled"),
send(State, #sm_failed{reason = 'unexpected-request',
text = xmpp:mk_text(Txt, Lang),
xmlns = Xmlns})
end;
_ ->
Txt = ?T("Unsupported version"),
send(State, #sm_failed{reason = 'unexpected-request',
text = xmpp:mk_text(Txt, Lang),
xmlns = Xmlns})
end.
-spec handle_enable(state(), sm_enable()) -> state().
handle_enable(#{mgmt_timeout := DefaultTimeout,
mgmt_queue_type := QueueType,
mgmt_max_timeout := MaxTimeout,
mgmt_xmlns := Xmlns, jid := JID} = State,
#sm_enable{resume = Resume, max = Max}) ->
State1 = State#{mgmt_id => make_id()},
Timeout = if Resume == false ->
0;
Max /= undefined, Max > 0, Max*1000 =< MaxTimeout ->
Max*1000;
true ->
DefaultTimeout
end,
Res = if Timeout > 0 ->
?DEBUG("Stream management with resumption enabled for ~ts",
[jid:encode(JID)]),
#sm_enabled{xmlns = Xmlns,
id = encode_id(State1),
resume = true,
max = Timeout div 1000};
true ->
?DEBUG("Stream management without resumption enabled for ~ts",
[jid:encode(JID)]),
#sm_enabled{xmlns = Xmlns}
end,
State2 = State1#{mgmt_state => active,
mgmt_queue => p1_queue:new(QueueType),
mgmt_timeout => Timeout},
send(State2, Res).
-spec handle_r(state()) -> state().
handle_r(#{mgmt_xmlns := Xmlns, mgmt_stanzas_in := H} = State) ->
Res = #sm_a{xmlns = Xmlns, h = H},
send(State, Res).
-spec handle_a(state(), sm_a()) -> state().
handle_a(State, #sm_a{h = H}) ->
State1 = check_h_attribute(State, H),
resend_rack(State1).
-spec handle_resume(state(), sm_resume()) -> {ok, state()} | {error, state()}.
handle_resume(#{user := User, lserver := LServer,
lang := Lang, socket := Socket} = State,
#sm_resume{h = H, previd = PrevID, xmlns = Xmlns}) ->
R = case inherit_session_state(State, PrevID) of
{ok, InheritedState} ->
{ok, InheritedState, H};
{error, Err, InH} ->
{error, #sm_failed{reason = 'item-not-found',
text = xmpp:mk_text(format_error(Err), Lang),
h = InH, xmlns = Xmlns}, Err};
{error, Err} ->
{error, #sm_failed{reason = 'item-not-found',
text = xmpp:mk_text(format_error(Err), Lang),
xmlns = Xmlns}, Err}
end,
case R of
{ok, #{jid := JID} = ResumedState, NumHandled} ->
State1 = check_h_attribute(ResumedState, NumHandled),
#{mgmt_xmlns := AttrXmlns, mgmt_stanzas_in := AttrH} = State1,
State2 = send(State1, #sm_resumed{xmlns = AttrXmlns,
h = AttrH,
previd = PrevID}),
State3 = resend_unacked_stanzas(State2),
State4 = send(State3, #sm_r{xmlns = AttrXmlns}),
State5 = ejabberd_hooks:run_fold(c2s_session_resumed, LServer, State4, []),
?INFO_MSG("(~ts) Resumed session for ~ts",
[xmpp_socket:pp(Socket), jid:encode(JID)]),
{ok, State5};
{error, El, Reason} ->
log_resumption_error(User, LServer, Reason),
{error, send(State, El)}
end.
-spec transition_to_pending(state(), _) -> state().
transition_to_pending(#{mgmt_state := active, mod := Mod,
mgmt_timeout := 0} = State, _Reason) ->
Mod:stop_async(self()),
State;
transition_to_pending(#{mgmt_state := active, jid := JID, socket := Socket,
lserver := LServer, mgmt_timeout := Timeout} = State,
Reason) ->
State1 = cancel_ack_timer(State),
?INFO_MSG("(~ts) Closing c2s connection for ~ts: ~ts; "
"waiting ~B seconds for stream resumption",
[xmpp_socket:pp(Socket), jid:encode(JID),
format_reason(State, Reason), Timeout div 1000]),
TRef = erlang:start_timer(Timeout, self(), pending_timeout),
State2 = State1#{mgmt_state => pending, mgmt_pending_timer => TRef},
ejabberd_hooks:run_fold(c2s_session_pending, LServer, State2, []);
transition_to_pending(State, _Reason) ->
State.
-spec check_h_attribute(state(), non_neg_integer()) -> state().
check_h_attribute(#{mgmt_stanzas_out := NumStanzasOut, jid := JID,
lang := Lang} = State, H)
when H > NumStanzasOut ->
?WARNING_MSG("~ts acknowledged ~B stanzas, but only ~B were sent",
[jid:encode(JID), H, NumStanzasOut]),
State1 = State#{mgmt_resend => false},
Err = xmpp:serr_undefined_condition(
?T("Client acknowledged more stanzas than sent by server"), Lang),
send(State1, Err);
check_h_attribute(#{mgmt_stanzas_out := NumStanzasOut, jid := JID} = State, H) ->
?DEBUG("~ts acknowledged ~B of ~B stanzas",
[jid:encode(JID), H, NumStanzasOut]),
mgmt_queue_drop(State, H).
-spec update_num_stanzas_in(state(), xmpp_element() | xmlel()) -> state().
update_num_stanzas_in(#{mgmt_state := MgmtState,
mgmt_stanzas_in := NumStanzasIn} = State, El)
when MgmtState == active; MgmtState == pending ->
NewNum = case {xmpp:is_stanza(El), NumStanzasIn} of
{true, 4294967295} ->
0;
{true, Num} ->
Num + 1;
{false, Num} ->
Num
end,
State#{mgmt_stanzas_in => NewNum};
update_num_stanzas_in(State, _El) ->
State.
-spec send_rack(state()) -> state().
send_rack(#{mgmt_ack_timer := _} = State) ->
State;
send_rack(#{mgmt_xmlns := Xmlns,
mgmt_stanzas_out := NumStanzasOut} = State) ->
State1 = State#{mgmt_stanzas_req => NumStanzasOut},
State2 = start_ack_timer(State1),
send(State2, #sm_r{xmlns = Xmlns}).
-spec resend_rack(state()) -> state().
resend_rack(#{mgmt_ack_timer := _,
mgmt_queue := Queue,
mgmt_stanzas_out := NumStanzasOut,
mgmt_stanzas_req := NumStanzasReq} = State) ->
State1 = cancel_ack_timer(State),
case NumStanzasReq < NumStanzasOut andalso not p1_queue:is_empty(Queue) of
true -> send_rack(State1);
false -> State1
end;
resend_rack(State) ->
State.
-spec mgmt_queue_add(state(), xmlel() | xmpp_element()) -> state().
mgmt_queue_add(#{mgmt_stanzas_out := NumStanzasOut,
mgmt_queue := Queue} = State, Pkt) ->
NewNum = case NumStanzasOut of
4294967295 -> 0;
Num -> Num + 1
end,
Queue1 = p1_queue:in({NewNum, erlang:timestamp(), Pkt}, Queue),
State1 = State#{mgmt_queue => Queue1, mgmt_stanzas_out => NewNum},
check_queue_length(State1).
-spec mgmt_queue_drop(state(), non_neg_integer()) -> state().
mgmt_queue_drop(#{mgmt_queue := Queue} = State, NumHandled) ->
NewQueue = p1_queue:dropwhile(
fun({N, _T, _E}) -> N =< NumHandled end, Queue),
State#{mgmt_queue => NewQueue}.
-spec check_queue_length(state()) -> state().
check_queue_length(#{mgmt_max_queue := Limit} = State)
when Limit == infinity; Limit == exceeded ->
State;
check_queue_length(#{mgmt_queue := Queue, mgmt_max_queue := Limit} = State) ->
case p1_queue:len(Queue) > Limit of
true ->
State#{mgmt_max_queue => exceeded};
false ->
State
end.
-spec route_late_queue_after_resume(state()) -> ok.
route_late_queue_after_resume(#{mgmt_queue := Queue, jid := JID})
when ?qlen(Queue) > 0 ->
?DEBUG("Re-routing ~B late queued packets to ~ts",
[p1_queue:len(Queue), jid:encode(JID)]),
p1_queue:foreach(
fun({_, _Time, Pkt}) ->
ejabberd_router:route(Pkt)
end, Queue);
route_late_queue_after_resume(_State) ->
ok.
-spec resend_unacked_stanzas(state()) -> state().
resend_unacked_stanzas(#{mgmt_state := MgmtState,
mgmt_queue := Queue,
jid := JID} = State)
when (MgmtState == active orelse
MgmtState == pending orelse
MgmtState == timeout) andalso ?qlen(Queue) > 0 ->
?DEBUG("Resending ~B unacknowledged stanza(s) to ~ts",
[p1_queue:len(Queue), jid:encode(JID)]),
p1_queue:foldl(
fun({_, Time, Pkt}, AccState) ->
Pkt1 = add_resent_delay_info(AccState, Pkt, Time),
Pkt2 = if ?is_stanza(Pkt1) ->
xmpp:put_meta(Pkt1, mgmt_is_resent, true);
true ->
Pkt1
end,
send(AccState, Pkt2)
end, State, Queue);
resend_unacked_stanzas(State) ->
State.
-spec route_unacked_stanzas(state()) -> ok.
route_unacked_stanzas(#{mgmt_state := MgmtState,
mgmt_resend := MgmtResend,
lang := Lang, user := User,
jid := JID, lserver := LServer,
mgmt_queue := Queue,
resource := Resource} = State)
when (MgmtState == active orelse
MgmtState == pending orelse
MgmtState == timeout) andalso ?qlen(Queue) > 0 ->
ResendOnTimeout = case MgmtResend of
Resend when is_boolean(Resend) ->
Resend;
if_offline ->
case ejabberd_sm:get_user_resources(User, LServer) of
[Resource] ->
%% Same resource opened new session
true;
[] -> true;
_ -> false
end
end,
?DEBUG("Re-routing ~B unacknowledged stanza(s) to ~ts",
[p1_queue:len(Queue), jid:encode(JID)]),
ModOfflineEnabled = gen_mod:is_loaded(LServer, mod_offline),
p1_queue:foreach(
fun({_, _Time, #presence{from = From}}) ->
?DEBUG("Dropping presence stanza from ~ts", [jid:encode(From)]);
({_, _Time, #iq{} = El}) ->
Txt = ?T("User session terminated"),
ejabberd_router:route_error(
El, xmpp:err_service_unavailable(Txt, Lang));
({_, _Time, #message{from = From, meta = #{carbon_copy := true}}}) ->
%% XEP-0280 says: "When a receiving server attempts to deliver a
%% forked message, and that message bounces with an error for
%% any reason, the receiving server MUST NOT forward that error
%% back to the original sender." Resending such a stanza could
%% easily lead to unexpected results as well.
?DEBUG("Dropping forwarded message stanza from ~ts",
[jid:encode(From)]);
({_, Time, #message{} = Msg}) ->
case {ModOfflineEnabled, ResendOnTimeout,
xmpp:get_meta(Msg, mam_archived, false)} of
Val when Val == {true, true, false};
Val == {true, true, true};
Val == {false, true, false} ->
NewEl = add_resent_delay_info(State, Msg, Time),
ejabberd_router:route(NewEl);
{_, _, true} ->
?DEBUG("Dropping archived message stanza from ~s",
[jid:encode(xmpp:get_from(Msg))]);
_ ->
Txt = ?T("User session terminated"),
ejabberd_router:route_error(
Msg, xmpp:err_service_unavailable(Txt, Lang))
end;
({_, _Time, El}) ->
%% Raw element of type 'error' resulting from a validation error
%% We cannot pass it to the router, it will generate an error
?DEBUG("Do not route raw element from ack queue: ~p", [El])
end, Queue);
route_unacked_stanzas(_State) ->
ok.
-spec inherit_session_state(state(), binary()) -> {ok, state()} |
{error, error_reason()} |
{error, error_reason(), non_neg_integer()}.
inherit_session_state(#{user := U, server := S,
mgmt_queue_type := QueueType} = State, PrevID) ->
case decode_id(PrevID) of
{ok, {R, MgmtID}} ->
case ejabberd_sm:get_session_sid(U, S, R) of
none ->
case pop_stanzas_in({U, S, R}, MgmtID) of
error ->
{error, session_not_found};
{ok, H} ->
{error, session_timed_out, H}
end;
{_, OldPID} = OldSID ->
try resume_session(OldPID, MgmtID, State) of
{resume, #{mgmt_xmlns := Xmlns,
mgmt_queue := Queue,
mgmt_timeout := Timeout,
mgmt_stanzas_in := NumStanzasIn,
mgmt_stanzas_out := NumStanzasOut} = OldState} ->
State1 = ejabberd_c2s:copy_state(State, OldState),
Queue1 = case QueueType of
ram -> Queue;
_ -> p1_queue:ram_to_file(Queue)
end,
State2 = State1#{sid => ejabberd_sm:make_sid(),
mgmt_id => MgmtID,
mgmt_xmlns => Xmlns,
mgmt_queue => Queue1,
mgmt_timeout => Timeout,
mgmt_stanzas_in => NumStanzasIn,
mgmt_stanzas_out => NumStanzasOut,
mgmt_state => active},
State3 = ejabberd_c2s:open_session(State2),
ejabberd_c2s:stop_async(OldPID),
{ok, State3};
{error, Msg} ->
{error, Msg}
catch exit:{noproc, _} ->
{error, session_is_dead};
exit:{normal, _} ->
{error, session_has_exited};
exit:{shutdown, _} ->
{error, session_has_exited};
exit:{killed, _} ->
{error, session_was_killed};
exit:{timeout, _} ->
ejabberd_sm:close_session(OldSID, U, S, R),
ejabberd_c2s:stop_async(OldPID),
{error, session_copy_timed_out}
end
end;
error ->
{error, invalid_previd}
end.
-spec resume_session(pid(), id(), state()) -> {resume, state()} |
{error, error_reason()}.
resume_session(PID, MgmtID, _State) ->
ejabberd_c2s:call(PID, {resume_session, MgmtID}, timer:seconds(15)).
-spec add_resent_delay_info(state(), stanza(), erlang:timestamp()) -> stanza();
(state(), xmlel(), erlang:timestamp()) -> xmlel().
add_resent_delay_info(#{lserver := LServer}, El, Time)
when is_record(El, message); is_record(El, presence) ->
misc:add_delay_info(El, jid:make(LServer), Time, <<"Resent">>);
add_resent_delay_info(_State, El, _Time) ->
%% TODO
El.
-spec send(state(), xmpp_element()) -> state().
send(#{mod := Mod} = State, Pkt) ->
Mod:send(State, Pkt).
-spec restart_pending_timer(state(), non_neg_integer()) -> state().
restart_pending_timer(#{mgmt_pending_timer := TRef} = State, NewTimeout) ->
misc:cancel_timer(TRef),
NewTRef = erlang:start_timer(NewTimeout, self(), pending_timeout),
State#{mgmt_pending_timer => NewTRef};
restart_pending_timer(State, _NewTimeout) ->
State.
-spec start_ack_timer(state()) -> state().
start_ack_timer(#{mgmt_ack_timeout := infinity} = State) ->
State;
start_ack_timer(#{mgmt_ack_timeout := AckTimeout} = State) ->
TRef = erlang:start_timer(AckTimeout, self(), ack_timeout),
State#{mgmt_ack_timer => TRef}.
-spec cancel_ack_timer(state()) -> state().
cancel_ack_timer(#{mgmt_ack_timer := TRef} = State) ->
misc:cancel_timer(TRef),
maps:remove(mgmt_ack_timer, State);
cancel_ack_timer(State) ->
State.
-spec need_to_enqueue(state(), xmlel() | stanza()) -> {boolean(), state()}.
need_to_enqueue(State, Pkt) when ?is_stanza(Pkt) ->
{not xmpp:get_meta(Pkt, mgmt_is_resent, false), State};
need_to_enqueue(#{mgmt_force_enqueue := true} = State, #xmlel{}) ->
State1 = maps:remove(mgmt_force_enqueue, State),
State2 = maps:remove(mgmt_is_resent, State1),
{true, State2};
need_to_enqueue(State, _) ->
{false, State}.
-spec make_id() -> id().
make_id() ->
p1_rand:bytes(8).
-spec encode_id(state()) -> binary().
encode_id(#{mgmt_id := MgmtID, resource := Resource}) ->
misc:term_to_base64({Resource, MgmtID}).
-spec decode_id(binary()) -> {ok, {binary(), id()}} | error.
decode_id(Encoded) ->
case misc:base64_to_term(Encoded) of
{term, {Resource, MgmtID}} when is_binary(Resource),
is_binary(MgmtID) ->
{ok, {Resource, MgmtID}};
_ ->
error
end.
%%%===================================================================
%%% Formatters and Logging
%%%===================================================================
-spec format_error(error_reason()) -> binary().
format_error(session_not_found) ->
?T("Previous session not found");
format_error(session_timed_out) ->
?T("Previous session timed out");
format_error(session_is_dead) ->
?T("Previous session PID is dead");
format_error(session_has_exited) ->
?T("Previous session PID has exited");
format_error(session_was_killed) ->
?T("Previous session PID has been killed");
format_error(session_copy_timed_out) ->
?T("Session state copying timed out");
format_error(invalid_previd) ->
?T("Invalid 'previd' value").
-spec format_reason(state(), term()) -> binary().
format_reason(_, ack_timeout) ->
<<"Timed out waiting for stream acknowledgement">>;
format_reason(#{stop_reason := {socket, ack_timeout}} = State, _) ->
format_reason(State, ack_timeout);
format_reason(State, Reason) ->
ejabberd_c2s:format_reason(State, Reason).
-spec log_resumption_error(binary(), binary(), error_reason()) -> ok.
log_resumption_error(User, Server, Reason)
when Reason == invalid_previd ->
?WARNING_MSG("Cannot resume session for ~ts@~ts: ~ts",
[User, Server, format_error(Reason)]);
log_resumption_error(User, Server, Reason) ->
?INFO_MSG("Cannot resume session for ~ts@~ts: ~ts",
[User, Server, format_error(Reason)]).
%%%===================================================================
%%% Cache-like storage for last handled stanzas
%%%===================================================================
init_cache(Opts) ->
ets_cache:new(?STREAM_MGMT_CACHE, cache_opts(Opts)).
cache_opts(Opts) ->
[{max_size, mod_stream_mgmt_opt:cache_size(Opts)},
{life_time, mod_stream_mgmt_opt:cache_life_time(Opts)},
{type, ordered_set}].
-spec store_stanzas_in(ljid(), id(), non_neg_integer()) -> boolean().
store_stanzas_in(LJID, MgmtID, Num) ->
ets_cache:insert(?STREAM_MGMT_CACHE, {LJID, MgmtID}, Num,
ejabberd_cluster:get_nodes()).
-spec pop_stanzas_in(ljid(), id()) -> {ok, non_neg_integer()} | error.
pop_stanzas_in(LJID, MgmtID) ->
case ets_cache:lookup(?STREAM_MGMT_CACHE, {LJID, MgmtID}) of
{ok, Val} ->
ets_cache:match_delete(?STREAM_MGMT_CACHE, {LJID, '_'},
ejabberd_cluster:get_nodes()),
{ok, Val};
error ->
error
end.
%%%===================================================================
%%% Configuration processing
%%%===================================================================
get_max_ack_queue(Host) ->
mod_stream_mgmt_opt:max_ack_queue(Host).
get_configured_resume_timeout(Host) ->
mod_stream_mgmt_opt:resume_timeout(Host).
get_max_resume_timeout(Host, ResumeTimeout) ->
case mod_stream_mgmt_opt:max_resume_timeout(Host) of
undefined -> ResumeTimeout;
Max when Max >= ResumeTimeout -> Max;
_ -> ResumeTimeout
end.
get_ack_timeout(Host) ->
mod_stream_mgmt_opt:ack_timeout(Host).
get_resend_on_timeout(Host) ->
mod_stream_mgmt_opt:resend_on_timeout(Host).
get_queue_type(Host) ->
mod_stream_mgmt_opt:queue_type(Host).
mod_opt_type(max_ack_queue) ->
econf:pos_int(infinity);
mod_opt_type(resume_timeout) ->
econf:either(
econf:int(0, 0),
econf:timeout(second));
mod_opt_type(max_resume_timeout) ->
econf:either(
econf:int(0, 0),
econf:timeout(second));
mod_opt_type(ack_timeout) ->
econf:timeout(second, infinity);
mod_opt_type(resend_on_timeout) ->
econf:either(
if_offline,
econf:bool());
mod_opt_type(cache_size) ->
econf:pos_int(infinity);
mod_opt_type(cache_life_time) ->
econf:timeout(second, infinity);
mod_opt_type(queue_type) ->
econf:queue_type().
mod_options(Host) ->
[{max_ack_queue, 5000},
{resume_timeout, timer:seconds(300)},
{max_resume_timeout, undefined},
{ack_timeout, timer:seconds(60)},
{cache_size, ejabberd_option:cache_size(Host)},
{cache_life_time, timer:hours(48)},
{resend_on_timeout, false},
{queue_type, ejabberd_option:queue_type(Host)}].
mod_doc() ->
#{desc =>
?T("This module adds support for "
"https://xmpp.org/extensions/xep-0198.html"
"[XEP-0198: Stream Management]. This protocol allows "
"active management of an XML stream between two XMPP "
"entities, including features for stanza acknowledgements "
"and stream resumption."),
opts =>
[{max_ack_queue,
#{value => ?T("Size"),
desc =>
?T("This option specifies the maximum number of "
"unacknowledged stanzas queued for possible "
"retransmission. When the limit is exceeded, "
"the client session is terminated. The allowed "
"values are positive integers and 'infinity'. "
"You should be careful when setting this value "
"as it should not be set too low, otherwise, "
"you could kill sessions in a loop, before they "
"get the chance to finish proper session initiation. "
"It should definitely be set higher that the size "
"of the offline queue (for example at least 3 times "
"the value of the max offline queue and never lower "
"than '1000'). The default value is '5000'.")}},
{resume_timeout,
#{value => "timeout()",
desc =>
?T("This option configures the (default) period of time "
"until a session times out if the connection is lost. "
"During this period of time, a client may resume its "
"session. Note that the client may request a different "
"timeout value, see the 'max_resume_timeout' option. "
"Setting it to '0' effectively disables session resumption. "
"The default value is '5' minutes.")}},
{max_resume_timeout,
#{value => "timeout()",
desc =>
?T("A client may specify the period of time until a session "
"times out if the connection is lost. During this period "
"of time, the client may resume its session. This option "
"limits the period of time a client is permitted to request. "
"It must be set to a timeout equal to or larger than the "
"default 'resume_timeout'. By default, it is set to the "
"same value as the 'resume_timeout' option.")}},
{ack_timeout,
#{value => "timeout()",
desc =>
?T("A time to wait for stanza acknowledgements. "
"Setting it to 'infinity' effectively disables the timeout. "
"The default value is '1' minute.")}},
{resend_on_timeout,
#{value => "true | false | if_offline",
desc =>
?T("If this option is set to 'true', any message stanzas "
"that weren't acknowledged by the client will be resent "
"on session timeout. This behavior might often be desired, "
"but could have unexpected results under certain circumstances. "
"For example, a message that was sent to two resources might "
"get resent to one of them if the other one timed out. "
"Therefore, the default value for this option is 'false', "
"which tells ejabberd to generate an error message instead. "
"As an alternative, the option may be set to 'if_offline'. "
"In this case, unacknowledged messages are resent only if "
"no other resource is online when the session times out. "
"Otherwise, error messages are generated.")}},
{queue_type,
#{value => "ram | file",
desc =>
?T("Same as top-level _`queue_type`_ option, but applied to this module only.")}},
{cache_size,
#{value => "pos_integer() | infinity",
desc =>
?T("Same as top-level _`cache_size`_ option, but applied to this module only.")}},
{cache_life_time,
#{value => "timeout()",
desc =>
?T("Same as top-level _`cache_life_time`_ option, "
"but applied to this module only. "
"The default value is '48 hours'.")}}]}.
