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xmpp.chapril.org-ejabberd/src/ejabberd_s2s.erl

757 lines
23 KiB
Erlang

%%%----------------------------------------------------------------------
%%% File : ejabberd_s2s.erl
%%% Author : Alexey Shchepin <alexey@process-one.net>
%%% Purpose : S2S connections manager
%%% Created : 7 Dec 2002 by Alexey Shchepin <alexey@process-one.net>
%%%
%%%
%%% ejabberd, Copyright (C) 2002-2017 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(ejabberd_s2s).
-protocol({xep, 220, '1.1'}).
-behaviour(ejabberd_config).
-author('alexey@process-one.net').
-behaviour(gen_server).
%% API
-export([start_link/0, route/3, have_connection/1,
make_key/2, get_connections_pids/1, try_register/1,
remove_connection/2, find_connection/2,
dirty_get_connections/0, allow_host/2,
incoming_s2s_number/0, outgoing_s2s_number/0,
stop_all_connections/0,
clean_temporarily_blocked_table/0,
list_temporarily_blocked_hosts/0,
external_host_overloaded/1, is_temporarly_blocked/1,
check_peer_certificate/3,
get_commands_spec/0]).
%% gen_server callbacks
-export([init/1, handle_call/3, handle_cast/2,
handle_info/2, terminate/2, code_change/3]).
-export([get_info_s2s_connections/1,
transform_options/1, opt_type/1]).
-include("ejabberd.hrl").
-include("logger.hrl").
-include("xmpp.hrl").
-include("ejabberd_commands.hrl").
-include_lib("public_key/include/public_key.hrl").
-define(PKIXEXPLICIT, 'OTP-PUB-KEY').
-define(PKIXIMPLICIT, 'OTP-PUB-KEY').
-include("XmppAddr.hrl").
-define(DEFAULT_MAX_S2S_CONNECTIONS_NUMBER, 1).
-define(DEFAULT_MAX_S2S_CONNECTIONS_NUMBER_PER_NODE, 1).
-define(S2S_OVERLOAD_BLOCK_PERIOD, 60).
%% once a server is temporarly blocked, it stay blocked for 60 seconds
-record(s2s, {fromto = {<<"">>, <<"">>} :: {binary(), binary()} | '_',
pid = self() :: pid() | '_' | '$1'}).
-record(state, {}).
-record(temporarily_blocked, {host = <<"">> :: binary(),
timestamp :: integer()}).
-type temporarily_blocked() :: #temporarily_blocked{}.
start_link() ->
gen_server:start_link({local, ?MODULE}, ?MODULE, [],
[]).
-spec route(jid(), jid(), xmpp_element()) -> ok.
route(From, To, Packet) ->
case catch do_route(From, To, Packet) of
{'EXIT', Reason} ->
?ERROR_MSG("~p~nwhen processing: ~p",
[Reason, {From, To, Packet}]);
_ -> ok
end.
clean_temporarily_blocked_table() ->
mnesia:clear_table(temporarily_blocked).
-spec list_temporarily_blocked_hosts() -> [temporarily_blocked()].
list_temporarily_blocked_hosts() ->
ets:tab2list(temporarily_blocked).
-spec external_host_overloaded(binary()) -> {aborted, any()} | {atomic, ok}.
external_host_overloaded(Host) ->
?INFO_MSG("Disabling connections from ~s for ~p "
"seconds",
[Host, ?S2S_OVERLOAD_BLOCK_PERIOD]),
mnesia:transaction(fun () ->
Time = p1_time_compat:monotonic_time(),
mnesia:write(#temporarily_blocked{host = Host,
timestamp = Time})
end).
-spec is_temporarly_blocked(binary()) -> boolean().
is_temporarly_blocked(Host) ->
case mnesia:dirty_read(temporarily_blocked, Host) of
[] -> false;
[#temporarily_blocked{timestamp = T} = Entry] ->
Diff = p1_time_compat:monotonic_time() - T,
case p1_time_compat:convert_time_unit(Diff, native, micro_seconds) of
N when N > (?S2S_OVERLOAD_BLOCK_PERIOD) * 1000 * 1000 ->
mnesia:dirty_delete_object(Entry), false;
_ -> true
end
end.
-spec remove_connection({binary(), binary()},
pid()) -> {atomic, ok} | ok | {aborted, any()}.
remove_connection(FromTo, Pid) ->
case catch mnesia:dirty_match_object(s2s,
#s2s{fromto = FromTo, pid = Pid})
of
[#s2s{pid = Pid}] ->
F = fun () ->
mnesia:delete_object(#s2s{fromto = FromTo, pid = Pid})
end,
mnesia:transaction(F);
_ -> ok
end.
-spec have_connection({binary(), binary()}) -> boolean().
have_connection(FromTo) ->
case catch mnesia:dirty_read(s2s, FromTo) of
[_] ->
true;
_ ->
false
end.
-spec get_connections_pids({binary(), binary()}) -> [pid()].
get_connections_pids(FromTo) ->
case catch mnesia:dirty_read(s2s, FromTo) of
L when is_list(L) ->
[Connection#s2s.pid || Connection <- L];
_ ->
[]
end.
-spec try_register({binary(), binary()}) -> boolean().
try_register(FromTo) ->
MaxS2SConnectionsNumber = max_s2s_connections_number(FromTo),
MaxS2SConnectionsNumberPerNode =
max_s2s_connections_number_per_node(FromTo),
F = fun () ->
L = mnesia:read({s2s, FromTo}),
NeededConnections = needed_connections_number(L,
MaxS2SConnectionsNumber,
MaxS2SConnectionsNumberPerNode),
if NeededConnections > 0 ->
mnesia:write(#s2s{fromto = FromTo, pid = self()}),
true;
true -> false
end
end,
case mnesia:transaction(F) of
{atomic, Res} -> Res;
_ -> false
end.
-spec dirty_get_connections() -> [{binary(), binary()}].
dirty_get_connections() ->
mnesia:dirty_all_keys(s2s).
check_peer_certificate(SockMod, Sock, Peer) ->
case SockMod:get_peer_certificate(Sock) of
{ok, Cert} ->
case SockMod:get_verify_result(Sock) of
0 ->
case ejabberd_idna:domain_utf8_to_ascii(Peer) of
false ->
{error, <<"Cannot decode remote server name">>};
AsciiPeer ->
case
lists:any(fun(D) -> match_domain(AsciiPeer, D) end,
get_cert_domains(Cert)) of
true ->
{ok, <<"Verification successful">>};
false ->
{error, <<"Certificate host name mismatch">>}
end
end;
VerifyRes ->
{error, fast_tls:get_cert_verify_string(VerifyRes, Cert)}
end;
{error, _Reason} ->
{error, <<"Cannot get peer certificate">>};
error ->
{error, <<"Cannot get peer certificate">>}
end.
-spec make_key({binary(), binary()}, binary()) -> binary().
make_key({From, To}, StreamID) ->
Secret = ejabberd_config:get_option(shared_key, fun(V) -> V end),
p1_sha:to_hexlist(
crypto:hmac(sha256, p1_sha:to_hexlist(crypto:hash(sha256, Secret)),
[To, " ", From, " ", StreamID])).
%%====================================================================
%% gen_server callbacks
%%====================================================================
init([]) ->
update_tables(),
ejabberd_mnesia:create(?MODULE, s2s,
[{ram_copies, [node()]},
{type, bag},
{attributes, record_info(fields, s2s)}]),
mnesia:add_table_copy(s2s, node(), ram_copies),
mnesia:subscribe(system),
ejabberd_commands:register_commands(get_commands_spec()),
ejabberd_mnesia:create(?MODULE, temporarily_blocked,
[{ram_copies, [node()]},
{attributes, record_info(fields, temporarily_blocked)}]),
{ok, #state{}}.
handle_call(_Request, _From, State) ->
{reply, ok, State}.
handle_cast(_Msg, State) ->
{noreply, State}.
handle_info({mnesia_system_event, {mnesia_down, Node}}, State) ->
clean_table_from_bad_node(Node),
{noreply, State};
handle_info({route, From, To, Packet}, State) ->
case catch do_route(From, To, Packet) of
{'EXIT', Reason} ->
?ERROR_MSG("~p~nwhen processing: ~p",
[Reason, {From, To, Packet}]);
_ -> ok
end,
{noreply, State};
handle_info(_Info, State) -> {noreply, State}.
terminate(_Reason, _State) ->
ejabberd_commands:unregister_commands(get_commands_spec()),
ok.
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
%%--------------------------------------------------------------------
%%% Internal functions
%%--------------------------------------------------------------------
-spec clean_table_from_bad_node(node()) -> any().
clean_table_from_bad_node(Node) ->
F = fun() ->
Es = mnesia:select(
s2s,
[{#s2s{pid = '$1', _ = '_'},
[{'==', {node, '$1'}, Node}],
['$_']}]),
lists:foreach(fun(E) ->
mnesia:delete_object(E)
end, Es)
end,
mnesia:async_dirty(F).
-spec do_route(jid(), jid(), stanza()) -> ok | false.
do_route(From, To, Packet) ->
?DEBUG("s2s manager~n\tfrom ~p~n\tto ~p~n\tpacket "
"~P~n",
[From, To, Packet, 8]),
case find_connection(From, To) of
{atomic, Pid} when is_pid(Pid) ->
?DEBUG("sending to process ~p~n", [Pid]),
#jid{lserver = MyServer} = From,
ejabberd_hooks:run(s2s_send_packet, MyServer,
[From, To, Packet]),
send_element(Pid, xmpp:set_from_to(Packet, From, To)),
ok;
{aborted, _Reason} ->
Lang = xmpp:get_lang(Packet),
Txt = <<"No s2s connection found">>,
Err = xmpp:err_service_unavailable(Txt, Lang),
ejabberd_router:route_error(To, From, Packet, Err),
false
end.
-spec find_connection(jid(), jid()) -> {aborted, any()} | {atomic, pid()}.
find_connection(From, To) ->
#jid{lserver = MyServer} = From,
#jid{lserver = Server} = To,
FromTo = {MyServer, Server},
MaxS2SConnectionsNumber =
max_s2s_connections_number(FromTo),
MaxS2SConnectionsNumberPerNode =
max_s2s_connections_number_per_node(FromTo),
?DEBUG("Finding connection for ~p~n", [FromTo]),
case catch mnesia:dirty_read(s2s, FromTo) of
{'EXIT', Reason} -> {aborted, Reason};
[] ->
%% We try to establish all the connections if the host is not a
%% service and if the s2s host is not blacklisted or
%% is in whitelist:
case not is_service(From, To) andalso
allow_host(MyServer, Server)
of
true ->
NeededConnections = needed_connections_number([],
MaxS2SConnectionsNumber,
MaxS2SConnectionsNumberPerNode),
open_several_connections(NeededConnections, MyServer,
Server, From, FromTo,
MaxS2SConnectionsNumber,
MaxS2SConnectionsNumberPerNode);
false -> {aborted, error}
end;
L when is_list(L) ->
NeededConnections = needed_connections_number(L,
MaxS2SConnectionsNumber,
MaxS2SConnectionsNumberPerNode),
if NeededConnections > 0 ->
%% We establish the missing connections for this pair.
open_several_connections(NeededConnections, MyServer,
Server, From, FromTo,
MaxS2SConnectionsNumber,
MaxS2SConnectionsNumberPerNode);
true ->
%% We choose a connexion from the pool of opened ones.
{atomic, choose_connection(From, L)}
end
end.
-spec choose_connection(jid(), [#s2s{}]) -> pid().
choose_connection(From, Connections) ->
choose_pid(From, [C#s2s.pid || C <- Connections]).
-spec choose_pid(jid(), [pid()]) -> pid().
choose_pid(From, Pids) ->
Pids1 = case [P || P <- Pids, node(P) == node()] of
[] -> Pids;
Ps -> Ps
end,
Pid =
lists:nth(erlang:phash(jid:remove_resource(From),
length(Pids1)),
Pids1),
?DEBUG("Using ejabberd_s2s_out ~p~n", [Pid]),
Pid.
open_several_connections(N, MyServer, Server, From,
FromTo, MaxS2SConnectionsNumber,
MaxS2SConnectionsNumberPerNode) ->
ConnectionsResult = [new_connection(MyServer, Server,
From, FromTo, MaxS2SConnectionsNumber,
MaxS2SConnectionsNumberPerNode)
|| _N <- lists:seq(1, N)],
case [PID || {atomic, PID} <- ConnectionsResult] of
[] -> hd(ConnectionsResult);
PIDs -> {atomic, choose_pid(From, PIDs)}
end.
new_connection(MyServer, Server, From, FromTo,
MaxS2SConnectionsNumber, MaxS2SConnectionsNumberPerNode) ->
{ok, Pid} = ejabberd_s2s_out:start(
MyServer, Server, new),
F = fun() ->
L = mnesia:read({s2s, FromTo}),
NeededConnections = needed_connections_number(L,
MaxS2SConnectionsNumber,
MaxS2SConnectionsNumberPerNode),
if NeededConnections > 0 ->
mnesia:write(#s2s{fromto = FromTo, pid = Pid}),
?INFO_MSG("New s2s connection started ~p", [Pid]),
Pid;
true -> choose_connection(From, L)
end
end,
TRes = mnesia:transaction(F),
case TRes of
{atomic, Pid} -> ejabberd_s2s_out:start_connection(Pid);
_ -> ejabberd_s2s_out:stop_connection(Pid)
end,
TRes.
-spec max_s2s_connections_number({binary(), binary()}) -> integer().
max_s2s_connections_number({From, To}) ->
case acl:match_rule(From, max_s2s_connections, jid:make(To)) of
Max when is_integer(Max) -> Max;
_ -> ?DEFAULT_MAX_S2S_CONNECTIONS_NUMBER
end.
-spec max_s2s_connections_number_per_node({binary(), binary()}) -> integer().
max_s2s_connections_number_per_node({From, To}) ->
case acl:match_rule(From, max_s2s_connections_per_node, jid:make(To)) of
Max when is_integer(Max) -> Max;
_ -> ?DEFAULT_MAX_S2S_CONNECTIONS_NUMBER_PER_NODE
end.
-spec needed_connections_number([#s2s{}], integer(), integer()) -> integer().
needed_connections_number(Ls, MaxS2SConnectionsNumber,
MaxS2SConnectionsNumberPerNode) ->
LocalLs = [L || L <- Ls, node(L#s2s.pid) == node()],
lists:min([MaxS2SConnectionsNumber - length(Ls),
MaxS2SConnectionsNumberPerNode - length(LocalLs)]).
%%--------------------------------------------------------------------
%% Function: is_service(From, To) -> true | false
%% Description: Return true if the destination must be considered as a
%% service.
%% --------------------------------------------------------------------
-spec is_service(jid(), jid()) -> boolean().
is_service(From, To) ->
LFromDomain = From#jid.lserver,
case ejabberd_config:get_option(
{route_subdomains, LFromDomain},
fun(s2s) -> s2s; (local) -> local end, local) of
s2s -> % bypass RFC 3920 10.3
false;
local ->
Hosts = (?MYHOSTS),
P = fun (ParentDomain) ->
lists:member(ParentDomain, Hosts)
end,
lists:any(P, parent_domains(To#jid.lserver))
end.
parent_domains(Domain) ->
lists:foldl(fun (Label, []) -> [Label];
(Label, [Head | Tail]) ->
[<<Label/binary, ".", Head/binary>>, Head | Tail]
end,
[], lists:reverse(str:tokens(Domain, <<".">>))).
send_element(Pid, El) ->
Pid ! {send_element, El}.
%%%----------------------------------------------------------------------
%%% ejabberd commands
get_commands_spec() ->
[#ejabberd_commands{
name = incoming_s2s_number,
tags = [stats, s2s],
desc = "Number of incoming s2s connections on the node",
policy = admin,
module = ?MODULE, function = incoming_s2s_number,
args = [], result = {s2s_incoming, integer}},
#ejabberd_commands{
name = outgoing_s2s_number,
tags = [stats, s2s],
desc = "Number of outgoing s2s connections on the node",
policy = admin,
module = ?MODULE, function = outgoing_s2s_number,
args = [], result = {s2s_outgoing, integer}},
#ejabberd_commands{name = stop_all_connections,
tags = [s2s],
desc = "Stop all outgoing and incoming connections",
policy = admin,
module = ?MODULE, function = stop_all_connections,
args = [], result = {res, rescode}}].
%% TODO Move those stats commands to ejabberd stats command ?
incoming_s2s_number() ->
supervisor_count(ejabberd_s2s_in_sup).
outgoing_s2s_number() ->
supervisor_count(ejabberd_s2s_out_sup).
supervisor_count(Supervisor) ->
case catch supervisor:which_children(Supervisor) of
{'EXIT', _} -> 0;
Result ->
length(Result)
end.
stop_all_connections() ->
lists:foreach(
fun({_Id, Pid, _Type, _Module}) ->
exit(Pid, kill)
end,
supervisor:which_children(ejabberd_s2s_in_sup) ++
supervisor:which_children(ejabberd_s2s_out_sup)),
mnesia:clear_table(s2s).
%%%----------------------------------------------------------------------
%%% Update Mnesia tables
update_tables() ->
case catch mnesia:table_info(s2s, type) of
bag -> ok;
{'EXIT', _} -> ok;
_ -> mnesia:delete_table(s2s)
end,
case catch mnesia:table_info(s2s, attributes) of
[fromto, node, key] ->
mnesia:transform_table(s2s, ignore, [fromto, pid]),
mnesia:clear_table(s2s);
[fromto, pid, key] ->
mnesia:transform_table(s2s, ignore, [fromto, pid]),
mnesia:clear_table(s2s);
[fromto, pid] -> ok;
{'EXIT', _} -> ok
end,
case lists:member(local_s2s, mnesia:system_info(tables)) of
true -> mnesia:delete_table(local_s2s);
false -> ok
end.
%% Check if host is in blacklist or white list
allow_host(MyServer, S2SHost) ->
allow_host2(MyServer, S2SHost) andalso
not is_temporarly_blocked(S2SHost).
allow_host2(MyServer, S2SHost) ->
Hosts = (?MYHOSTS),
case lists:dropwhile(fun (ParentDomain) ->
not lists:member(ParentDomain, Hosts)
end,
parent_domains(MyServer))
of
[MyHost | _] -> allow_host1(MyHost, S2SHost);
[] -> allow_host1(MyServer, S2SHost)
end.
allow_host1(MyHost, S2SHost) ->
Rule = ejabberd_config:get_option(
s2s_access,
fun(A) -> A end,
all),
JID = jid:make(S2SHost),
case acl:match_rule(MyHost, Rule, JID) of
deny -> false;
allow ->
case ejabberd_hooks:run_fold(s2s_allow_host, MyHost,
allow, [MyHost, S2SHost]) of
deny -> false;
allow -> true;
_ -> true
end
end.
transform_options(Opts) ->
lists:foldl(fun transform_options/2, [], Opts).
transform_options({{s2s_host, Host}, Action}, Opts) ->
?WARNING_MSG("Option 's2s_host' is deprecated. "
"The option is still supported but it is better to "
"fix your config: use access rules instead.", []),
ACLName = jlib:binary_to_atom(
iolist_to_binary(["s2s_access_", Host])),
[{acl, ACLName, {server, Host}},
{access, s2s, [{Action, ACLName}]},
{s2s_access, s2s} |
Opts];
transform_options({s2s_default_policy, Action}, Opts) ->
?WARNING_MSG("Option 's2s_default_policy' is deprecated. "
"The option is still supported but it is better to "
"fix your config: "
"use 's2s_access' with an access rule.", []),
[{access, s2s, [{Action, all}]},
{s2s_access, s2s} |
Opts];
transform_options(Opt, Opts) ->
[Opt|Opts].
%% Get information about S2S connections of the specified type.
%% @spec (Type) -> [Info]
%% where Type = in | out
%% Info = [{InfoName::atom(), InfoValue::any()}]
get_info_s2s_connections(Type) ->
ChildType = case Type of
in -> ejabberd_s2s_in_sup;
out -> ejabberd_s2s_out_sup
end,
Connections = supervisor:which_children(ChildType),
get_s2s_info(Connections, Type).
get_s2s_info(Connections, Type) ->
complete_s2s_info(Connections, Type, []).
complete_s2s_info([], _, Result) -> Result;
complete_s2s_info([Connection | T], Type, Result) ->
{_, PID, _, _} = Connection,
State = get_s2s_state(PID),
complete_s2s_info(T, Type, [State | Result]).
-spec get_s2s_state(pid()) -> [{status, open | closed | error} | {s2s_pid, pid()}].
get_s2s_state(S2sPid) ->
Infos = case gen_fsm:sync_send_all_state_event(S2sPid,
get_state_infos)
of
{state_infos, Is} -> [{status, open} | Is];
{noproc, _} -> [{status, closed}]; %% Connection closed
{badrpc, _} -> [{status, error}]
end,
[{s2s_pid, S2sPid} | Infos].
get_cert_domains(Cert) ->
TBSCert = Cert#'Certificate'.tbsCertificate,
Subject = case TBSCert#'TBSCertificate'.subject of
{rdnSequence, Subj} -> lists:flatten(Subj);
_ -> []
end,
Extensions = case TBSCert#'TBSCertificate'.extensions of
Exts when is_list(Exts) -> Exts;
_ -> []
end,
lists:flatmap(fun (#'AttributeTypeAndValue'{type =
?'id-at-commonName',
value = Val}) ->
case 'OTP-PUB-KEY':decode('X520CommonName', Val) of
{ok, {_, D1}} ->
D = if is_binary(D1) -> D1;
is_list(D1) -> list_to_binary(D1);
true -> error
end,
if D /= error ->
case jid:from_string(D) of
#jid{luser = <<"">>, lserver = LD,
lresource = <<"">>} ->
[LD];
_ -> []
end;
true -> []
end;
_ -> []
end;
(_) -> []
end,
Subject)
++
lists:flatmap(fun (#'Extension'{extnID =
?'id-ce-subjectAltName',
extnValue = Val}) ->
BVal = if is_list(Val) -> list_to_binary(Val);
true -> Val
end,
case 'OTP-PUB-KEY':decode('SubjectAltName', BVal)
of
{ok, SANs} ->
lists:flatmap(fun ({otherName,
#'AnotherName'{'type-id' =
?'id-on-xmppAddr',
value =
XmppAddr}}) ->
case
'XmppAddr':decode('XmppAddr',
XmppAddr)
of
{ok, D}
when
is_binary(D) ->
case
jid:from_string((D))
of
#jid{luser =
<<"">>,
lserver =
LD,
lresource =
<<"">>} ->
case
ejabberd_idna:domain_utf8_to_ascii(LD)
of
false ->
[];
PCLD ->
[PCLD]
end;
_ -> []
end;
_ -> []
end;
({dNSName, D})
when is_list(D) ->
case
jid:from_string(list_to_binary(D))
of
#jid{luser = <<"">>,
lserver = LD,
lresource =
<<"">>} ->
[LD];
_ -> []
end;
(_) -> []
end,
SANs);
_ -> []
end;
(_) -> []
end,
Extensions).
match_domain(Domain, Domain) -> true;
match_domain(Domain, Pattern) ->
DLabels = str:tokens(Domain, <<".">>),
PLabels = str:tokens(Pattern, <<".">>),
match_labels(DLabels, PLabels).
match_labels([], []) -> true;
match_labels([], [_ | _]) -> false;
match_labels([_ | _], []) -> false;
match_labels([DL | DLabels], [PL | PLabels]) ->
case lists:all(fun (C) ->
$a =< C andalso C =< $z orelse
$0 =< C andalso C =< $9 orelse
C == $- orelse C == $*
end,
binary_to_list(PL))
of
true ->
Regexp = ejabberd_regexp:sh_to_awk(PL),
case ejabberd_regexp:run(DL, Regexp) of
match -> match_labels(DLabels, PLabels);
nomatch -> false
end;
false -> false
end.
opt_type(route_subdomains) ->
fun (s2s) -> s2s;
(local) -> local
end;
opt_type(s2s_access) ->
fun acl:access_rules_validator/1;
opt_type(_) -> [route_subdomains, s2s_access].