%%%----------------------------------------------------------------------
%%% File : ejabberd_auth_ldap.erl
%%% Author : Alexey Shchepin <alexey@process-one.net>
%%% Purpose : Authentication via LDAP
%%% Created : 12 Dec 2004 by Alexey Shchepin <alexey@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(ejabberd_auth_ldap).
-author('alexey@process-one.net').
-behaviour(gen_server).
-behaviour(ejabberd_auth).
%% gen_server callbacks
-export([init/1, handle_info/2, handle_call/3,
handle_cast/2, terminate/2, code_change/3]).
-export([start/1, stop/1, start_link/1, set_password/3,
check_password/4, user_exists/2,
get_users/2, count_users/2,
store_type/1, plain_password_required/1,
reload/1]).
-include("logger.hrl").
-include("eldap.hrl").
-record(state,
{host = <<"">> :: binary(),
eldap_id = <<"">> :: binary(),
bind_eldap_id = <<"">> :: binary(),
servers = [] :: [binary()],
backups = [] :: [binary()],
port = ?LDAP_PORT :: inet:port_number(),
tls_options = [] :: list(),
dn = <<"">> :: binary(),
password = <<"">> :: binary(),
base = <<"">> :: binary(),
uids = [] :: [{binary()} | {binary(), binary()}],
ufilter = <<"">> :: binary(),
sfilter = <<"">> :: binary(),
deref_aliases = never :: never | searching | finding | always,
dn_filter :: binary() | undefined,
dn_filter_attrs = [] :: [binary()]}).
handle_cast(Msg, State) ->
?WARNING_MSG("Unexpected cast: ~p", [Msg]),
{noreply, State}.
code_change(_OldVsn, State, _Extra) -> {ok, State}.
handle_info(Info, State) ->
?WARNING_MSG("Unexpected info: ~p", [Info]),
{noreply, State}.
-define(LDAP_SEARCH_TIMEOUT, 5).
%%%----------------------------------------------------------------------
%%% API
%%%----------------------------------------------------------------------
start(Host) ->
Proc = gen_mod:get_module_proc(Host, ?MODULE),
ChildSpec = {Proc, {?MODULE, start_link, [Host]},
transient, 1000, worker, [?MODULE]},
supervisor:start_child(ejabberd_backend_sup, ChildSpec).
stop(Host) ->
Proc = gen_mod:get_module_proc(Host, ?MODULE),
case supervisor:terminate_child(ejabberd_backend_sup, Proc) of
ok -> supervisor:delete_child(ejabberd_backend_sup, Proc);
Err -> Err
end.
start_link(Host) ->
Proc = gen_mod:get_module_proc(Host, ?MODULE),
gen_server:start_link({local, Proc}, ?MODULE, Host, []).
terminate(_Reason, _State) -> ok.
init(Host) ->
process_flag(trap_exit, true),
State = parse_options(Host),
eldap_pool:start_link(State#state.eldap_id,
State#state.servers, State#state.backups,
State#state.port, State#state.dn,
State#state.password, State#state.tls_options),
eldap_pool:start_link(State#state.bind_eldap_id,
State#state.servers, State#state.backups,
State#state.port, State#state.dn,
State#state.password, State#state.tls_options),
{ok, State}.
reload(Host) ->
stop(Host),
start(Host).
plain_password_required(_) -> true.
store_type(_) -> external.
check_password(User, AuthzId, Server, Password) ->
if AuthzId /= <<>> andalso AuthzId /= User ->
{nocache, false};
Password == <<"">> ->
{nocache, false};
true ->
case catch check_password_ldap(User, Server, Password) of
{'EXIT', _} -> {nocache, false};
Result -> {cache, Result}
end
end.
set_password(User, Server, Password) ->
{ok, State} = eldap_utils:get_state(Server, ?MODULE),
case find_user_dn(User, State) of
false -> {cache, {error, db_failure}};
DN ->
case eldap_pool:modify_passwd(State#state.eldap_id, DN,
Password) of
ok -> {cache, {ok, Password}};
_Err -> {nocache, {error, db_failure}}
end
end.
get_users(Server, []) ->
case catch get_users_ldap(Server) of
{'EXIT', _} -> [];
Result -> Result
end.
count_users(Server, Opts) ->
length(get_users(Server, Opts)).
user_exists(User, Server) ->
case catch user_exists_ldap(User, Server) of
{'EXIT', _Error} -> {nocache, {error, db_failure}};
Result -> {cache, Result}
end.
%%%----------------------------------------------------------------------
%%% Internal functions
%%%----------------------------------------------------------------------
check_password_ldap(User, Server, Password) ->
{ok, State} = eldap_utils:get_state(Server, ?MODULE),
case find_user_dn(User, State) of
false -> false;
DN ->
case eldap_pool:bind(State#state.bind_eldap_id, DN,
Password)
of
ok -> true;
_ -> false
end
end.
get_users_ldap(Server) ->
{ok, State} = eldap_utils:get_state(Server, ?MODULE),
UIDs = State#state.uids,
Eldap_ID = State#state.eldap_id,
Server = State#state.host,
ResAttrs = result_attrs(State),
case eldap_filter:parse(State#state.sfilter) of
{ok, EldapFilter} ->
case eldap_pool:search(Eldap_ID,
[{base, State#state.base},
{filter, EldapFilter},
{timeout, ?LDAP_SEARCH_TIMEOUT},
{deref_aliases, State#state.deref_aliases},
{attributes, ResAttrs}])
of
#eldap_search_result{entries = Entries} ->
lists:flatmap(fun (#eldap_entry{attributes = Attrs,
object_name = DN}) ->
case is_valid_dn(DN, Attrs, State) of
false -> [];
_ ->
case
eldap_utils:find_ldap_attrs(UIDs,
Attrs)
of
<<"">> -> [];
{User, UIDFormat} ->
case
eldap_utils:get_user_part(User,
UIDFormat)
of
{ok, U} ->
case jid:nodeprep(U) of
error -> [];
LU ->
[{LU,
jid:nameprep(Server)}]
end;
_ -> []
end
end
end
end,
Entries);
_ -> []
end;
_ -> []
end.
user_exists_ldap(User, Server) ->
{ok, State} = eldap_utils:get_state(Server, ?MODULE),
case find_user_dn(User, State) of
false -> false;
_DN -> true
end.
handle_call(get_state, _From, State) ->
{reply, {ok, State}, State};
handle_call(stop, _From, State) ->
{stop, normal, ok, State};
handle_call(Request, From, State) ->
?WARNING_MSG("Unexpected call from ~p: ~p", [From, Request]),
{noreply, State}.
find_user_dn(User, State) ->
ResAttrs = result_attrs(State),
case eldap_filter:parse(State#state.ufilter,
[{<<"%u">>, User}])
of
{ok, Filter} ->
case eldap_pool:search(State#state.eldap_id,
[{base, State#state.base}, {filter, Filter},
{deref_aliases, State#state.deref_aliases},
{attributes, ResAttrs}])
of
#eldap_search_result{entries =
[#eldap_entry{attributes = Attrs,
object_name = DN}
| _]} ->
is_valid_dn(DN, Attrs, State);
_ -> false
end;
_ -> false
end.
%% Check that the DN is valid, based on the dn filter
is_valid_dn(DN, _, #state{dn_filter = undefined}) -> DN;
is_valid_dn(DN, Attrs, State) ->
DNAttrs = State#state.dn_filter_attrs,
UIDs = State#state.uids,
Values = [{<<"%s">>,
eldap_utils:get_ldap_attr(Attr, Attrs), 1}
|| Attr <- DNAttrs],
SubstValues = case eldap_utils:find_ldap_attrs(UIDs,
Attrs)
of
<<"">> -> Values;
{S, UAF} ->
case eldap_utils:get_user_part(S, UAF) of
{ok, U} -> [{<<"%u">>, U} | Values];
_ -> Values
end
end
++ [{<<"%d">>, State#state.host}, {<<"%D">>, DN}],
case eldap_filter:parse(State#state.dn_filter,
SubstValues)
of
{ok, EldapFilter} ->
case eldap_pool:search(State#state.eldap_id,
[{base, State#state.base},
{filter, EldapFilter},
{deref_aliases, State#state.deref_aliases},
{attributes, [<<"dn">>]}])
of
#eldap_search_result{entries = [_ | _]} -> DN;
_ -> false
end;
_ -> false
end.
result_attrs(#state{uids = UIDs,
dn_filter_attrs = DNFilterAttrs}) ->
lists:foldl(fun ({UID}, Acc) -> [UID | Acc];
({UID, _}, Acc) -> [UID | Acc]
end,
DNFilterAttrs, UIDs).
%%%----------------------------------------------------------------------
%%% Auxiliary functions
%%%----------------------------------------------------------------------
parse_options(Host) ->
Cfg = ?eldap_config(ejabberd_option, Host),
Eldap_ID = misc:atom_to_binary(gen_mod:get_module_proc(Host, ?MODULE)),
Bind_Eldap_ID = misc:atom_to_binary(
gen_mod:get_module_proc(Host, bind_ejabberd_auth_ldap)),
UIDsTemp = ejabberd_option:ldap_uids(Host),
UIDs = eldap_utils:uids_domain_subst(Host, UIDsTemp),
SubFilter = eldap_utils:generate_subfilter(UIDs),
UserFilter = case ejabberd_option:ldap_filter(Host) of
<<"">> ->
SubFilter;
F ->
<<"(&", SubFilter/binary, F/binary, ")">>
end,
SearchFilter = eldap_filter:do_sub(UserFilter, [{<<"%u">>, <<"*">>}]),
{DNFilter, DNFilterAttrs} = ejabberd_option:ldap_dn_filter(Host),
#state{host = Host, eldap_id = Eldap_ID,
bind_eldap_id = Bind_Eldap_ID,
servers = Cfg#eldap_config.servers,
backups = Cfg#eldap_config.backups,
port = Cfg#eldap_config.port,
tls_options = Cfg#eldap_config.tls_options,
dn = Cfg#eldap_config.dn,
password = Cfg#eldap_config.password,
base = Cfg#eldap_config.base,
deref_aliases = Cfg#eldap_config.deref_aliases,
uids = UIDs, ufilter = UserFilter,
sfilter = SearchFilter,
dn_filter = DNFilter, dn_filter_attrs = DNFilterAttrs}.
