%%%----------------------------------------------------------------------
%%% File : mod_jidprep.erl
%%% Author : Holger Weiss <holger@zedat.fu-berlin.de>
%%% Purpose : JID Prep (XEP-0328)
%%% Created : 11 Sep 2019 by Holger Weiss <holger@zedat.fu-berlin.de>
%%%
%%%
%%% ejabberd, Copyright (C) 2019-2022 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_jidprep).
-author('holger@zedat.fu-berlin.de').
-protocol({xep, 328, '0.1', '19.09', "", ""}).
-behaviour(gen_mod).
%% gen_mod callbacks.
-export([start/2, stop/1, reload/3, mod_opt_type/1, mod_options/1, depends/2]).
-export([mod_doc/0]).
%% ejabberd_hooks callbacks.
-export([disco_local_features/5]).
%% gen_iq_handler callback.
-export([process_iq/1]).
-include("logger.hrl").
-include("translate.hrl").
-include_lib("xmpp/include/xmpp.hrl").
%%--------------------------------------------------------------------
%% gen_mod callbacks.
%%--------------------------------------------------------------------
-spec start(binary(), gen_mod:opts()) -> ok.
start(Host, _Opts) ->
register_iq_handlers(Host),
register_hooks(Host).
-spec stop(binary()) -> ok.
stop(Host) ->
unregister_hooks(Host),
unregister_iq_handlers(Host).
-spec reload(binary(), gen_mod:opts(), gen_mod:opts()) -> ok.
reload(_Host, _NewOpts, _OldOpts) ->
ok.
-spec depends(binary(), gen_mod:opts()) -> [{module(), hard | soft}].
depends(_Host, _Opts) ->
[].
-spec mod_opt_type(atom()) -> econf:validator().
mod_opt_type(access) ->
econf:acl().
-spec mod_options(binary()) -> [{atom(), any()}].
mod_options(_Host) ->
[{access, local}].
mod_doc() ->
#{desc =>
?T("This module allows XMPP clients to ask the "
"server to normalize a JID as per the rules specified "
"in https://tools.ietf.org/html/rfc6122"
"[RFC 6122: XMPP Address Format]. This might be useful "
"for clients in certain constrained environments, "
"or for testing purposes."),
opts =>
[{access,
#{value => ?T("AccessName"),
desc =>
?T("This option defines which access rule will "
"be used to control who is allowed to use this "
"service. The default value is 'local'.")}}]}.
%%--------------------------------------------------------------------
%% Register/unregister hooks.
%%--------------------------------------------------------------------
-spec register_hooks(binary()) -> ok.
register_hooks(Host) ->
ejabberd_hooks:add(disco_local_features, Host, ?MODULE,
disco_local_features, 50).
-spec unregister_hooks(binary()) -> ok.
unregister_hooks(Host) ->
ejabberd_hooks:delete(disco_local_features, Host, ?MODULE,
disco_local_features, 50).
%%--------------------------------------------------------------------
%% Service discovery.
%%--------------------------------------------------------------------
-spec disco_local_features(mod_disco:features_acc(), jid(), jid(), binary(),
binary()) -> mod_disco:features_acc().
disco_local_features(empty, From, To, Node, Lang) ->
disco_local_features({result, []}, From, To, Node, Lang);
disco_local_features({result, OtherFeatures} = Acc, From,
#jid{lserver = LServer}, <<"">>, _Lang) ->
Access = mod_jidprep_opt:access(LServer),
case acl:match_rule(LServer, Access, From) of
allow ->
{result, [?NS_JIDPREP_0 | OtherFeatures]};
deny ->
Acc
end;
disco_local_features(Acc, _From, _To, _Node, _Lang) ->
Acc.
%%--------------------------------------------------------------------
%% IQ handlers.
%%--------------------------------------------------------------------
-spec register_iq_handlers(binary()) -> ok.
register_iq_handlers(Host) ->
gen_iq_handler:add_iq_handler(ejabberd_local, Host,
?NS_JIDPREP_0, ?MODULE, process_iq).
-spec unregister_iq_handlers(binary()) -> ok.
unregister_iq_handlers(Host) ->
gen_iq_handler:remove_iq_handler(ejabberd_local, Host, ?NS_JIDPREP_0).
-spec process_iq(iq()) -> iq().
process_iq(#iq{type = set, lang = Lang} = IQ) ->
Txt = ?T("Value 'set' of 'type' attribute is not allowed"),
xmpp:make_error(IQ, xmpp:err_not_allowed(Txt, Lang));
process_iq(#iq{from = From, to = #jid{lserver = LServer}, lang = Lang,
sub_els = [#jidprep{jid = #jid{luser = U,
lserver = S,
lresource = R} = JID}]} = IQ) ->
Access = mod_jidprep_opt:access(LServer),
case acl:match_rule(LServer, Access, From) of
allow ->
case jid:make(U, S, R) of
#jid{} = Normalized ->
?DEBUG("Normalized JID for ~ts: ~ts",
[jid:encode(From), jid:encode(JID)]),
xmpp:make_iq_result(IQ, #jidprep{jid = Normalized});
error -> % Cannot happen.
?DEBUG("Normalizing JID failed for ~ts: ~ts",
[jid:encode(From), jid:encode(JID)]),
Txt = ?T("JID normalization failed"),
xmpp:make_error(IQ, xmpp:err_jid_malformed(Txt, Lang))
end;
deny ->
?DEBUG("Won't return normalized JID to ~ts: ~ts",
[jid:encode(From), jid:encode(JID)]),
Txt = ?T("JID normalization denied by service policy"),
xmpp:make_error(IQ, xmpp:err_forbidden(Txt, Lang))
end;
process_iq(#iq{lang = Lang} = IQ) ->
Txt = ?T("No module is handling this query"),
xmpp:make_error(IQ, xmpp:err_service_unavailable(Txt, Lang)).
