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Diffstat (limited to 'src/eldap_filter.erl')
| -rw-r--r-- | src/eldap_filter.erl | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/src/eldap_filter.erl b/src/eldap_filter.erl new file mode 100644 index 000000000..6771fc2af --- /dev/null +++ b/src/eldap_filter.erl @@ -0,0 +1,191 @@ +%%%---------------------------------------------------------------------- +%%% File: eldap_filter.erl +%%% Purpose: Converts String Representation of +%%% LDAP Search Filter (RFC 2254) +%%% to eldap's representation of filter +%%% Author: Evgeniy Khramtsov <ekhramtsov@process-one.net> +%%% +%%% +%%% ejabberd, Copyright (C) 2002-2013 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., 59 Temple Place, Suite 330, Boston, MA +%%% 02111-1307 USA +%%% +%%%---------------------------------------------------------------------- +-module(eldap_filter). + +%% TODO: remove this when new regexp module will be used +-export([parse/1, parse/2, do_sub/2]). + +%%==================================================================== +%% API +%%==================================================================== +%%%------------------------------------------------------------------- +%%% Arity: parse/1 +%%% Function: parse(RFC2254_Filter) -> {ok, EldapFilter} | +%%% {error, bad_filter} +%%% +%%% RFC2254_Filter = string(). +%%% +%%% Description: Converts String Representation of LDAP Search Filter (RFC 2254) +%%% to eldap's representation of filter. +%%% +%%% Example: +%%% > eldap_filter:parse("(&(!(uid<=100))(mail=*))"). +%%% +%%% {ok,{'and',[{'not',{lessOrEqual,{'AttributeValueAssertion',"uid","100"}}}, +%%% {present,"mail"}]}} +%%%------------------------------------------------------------------- +-spec parse(binary()) -> {error, any()} | {ok, eldap:filter()}. + +parse(L) -> + parse(L, []). + +%%%------------------------------------------------------------------- +%%% Arity: parse/2 +%%% Function: parse(RFC2254_Filter, [SubstValue |...]) -> +%%% {ok, EldapFilter} | +%%% {error, bad_filter} | +%%% {error, bad_regexp} | +%%% {error, max_substitute_recursion} +%%% +%%% SubstValue = {RegExp, Value} | {RegExp, Value, N}, +%%% RFC2254_Filter = RegExp = Value = string(), +%%% N = integer(). +%%% +%%% Description: The same as parse/1, but substitutes N or all occurences +%%% of RegExp with Value *after* parsing. +%%% +%%% Example: +%%% > eldap_filter:parse( +%%% "(|(mail=%u@%d)(jid=%u@%d))", +%%% [{"%u", "xramtsov"},{"%d","gmail.com"}]). +%%% +%%% {ok,{'or',[{equalityMatch,{'AttributeValueAssertion', +%%% "mail", +%%% "xramtsov@gmail.com"}}, +%%% {equalityMatch,{'AttributeValueAssertion', +%%% "jid", +%%% "xramtsov@gmail.com"}}]}} +%%%------------------------------------------------------------------- +-spec parse(binary(), [{binary(), binary()} | + {binary(), binary(), pos_integer()}]) -> + {error, any()} | {ok, eldap:filter()}. + +parse(L, SList) -> + case catch eldap_filter_yecc:parse(scan(binary_to_list(L), SList)) of + {'EXIT', _} = Err -> + {error, Err}; + {error, {_, _, Msg}} -> + {error, Msg}; + {ok, Result} -> + {ok, Result}; + {regexp, Err} -> + {error, Err} + end. + +%%==================================================================== +%% Internal functions +%%==================================================================== +-define(do_scan(L), scan(Rest, <<>>, [{L, 1} | check(Buf, S) ++ Result], L, S)). + +scan(L, SList) -> + scan(L, <<"">>, [], undefined, SList). + +scan("=*)" ++ Rest, Buf, Result, '(', S) -> + scan(Rest, <<>>, [{')', 1}, {'=*', 1} | check(Buf, S) ++ Result], ')', S); +scan(":dn" ++ Rest, Buf, Result, '(', S) -> ?do_scan(':dn'); +scan(":=" ++ Rest, Buf, Result, '(', S) -> ?do_scan(':='); +scan(":=" ++ Rest, Buf, Result, ':dn', S) -> ?do_scan(':='); +scan(":=" ++ Rest, Buf, Result, ':', S) -> ?do_scan(':='); +scan("~=" ++ Rest, Buf, Result, '(', S) -> ?do_scan('~='); +scan(">=" ++ Rest, Buf, Result, '(', S) -> ?do_scan('>='); +scan("<=" ++ Rest, Buf, Result, '(', S) -> ?do_scan('<='); +scan("=" ++ Rest, Buf, Result, '(', S) -> ?do_scan('='); +scan(":" ++ Rest, Buf, Result, '(', S) -> ?do_scan(':'); +scan(":" ++ Rest, Buf, Result, ':dn', S) -> ?do_scan(':'); +scan("&" ++ Rest, Buf, Result, '(', S) when Buf==<<"">> -> ?do_scan('&'); +scan("|" ++ Rest, Buf, Result, '(', S) when Buf==<<"">> -> ?do_scan('|'); +scan("!" ++ Rest, Buf, Result, '(', S) when Buf==<<"">> -> ?do_scan('!'); +scan("*" ++ Rest, Buf, Result, '*', S) -> ?do_scan('*'); +scan("*" ++ Rest, Buf, Result, '=', S) -> ?do_scan('*'); +scan("(" ++ Rest, Buf, Result, _, S) -> ?do_scan('('); +scan(")" ++ Rest, Buf, Result, _, S) -> ?do_scan(')'); +scan([Letter | Rest], Buf, Result, PreviosAtom, S) -> + scan(Rest, <<Buf/binary, Letter>>, Result, PreviosAtom, S); +scan([], Buf, Result, _, S) -> + lists:reverse(check(Buf, S) ++ Result). + +check(<<>>, _) -> + []; +check(Buf, S) -> + [{str, 1, binary_to_list(do_sub(Buf, S))}]. + +-define(MAX_RECURSION, 100). + +-spec do_sub(binary(), [{binary(), binary()} | + {binary(), binary(), pos_integer()}]) -> binary(). + +do_sub(S, []) -> + S; +do_sub(<<>>, _) -> + <<>>; +do_sub(S, [{RegExp, New} | T]) -> + Result = do_sub(S, {RegExp, replace_amps(New)}, 1), + do_sub(Result, T); +do_sub(S, [{RegExp, New, Times} | T]) -> + Result = do_sub(S, {RegExp, replace_amps(New), Times}, 1), + do_sub(Result, T). + +do_sub(S, {RegExp, New}, Iter) -> + case ejabberd_regexp:run(S, RegExp) of + match -> + case ejabberd_regexp:replace(S, RegExp, New) of + NewS when Iter =< ?MAX_RECURSION -> + do_sub(NewS, {RegExp, New}, Iter+1); + _NewS when Iter > ?MAX_RECURSION -> + erlang:error(max_substitute_recursion) + end; + nomatch -> + S; + _ -> + erlang:error(bad_regexp) + end; + +do_sub(S, {_, _, N}, _) when N<1 -> + S; + +do_sub(S, {RegExp, New, Times}, Iter) -> + case ejabberd_regexp:run(S, RegExp) of + match -> + case ejabberd_regexp:replace(S, RegExp, New) of + NewS when Iter < Times -> + do_sub(NewS, {RegExp, New, Times}, Iter+1); + NewS -> + NewS + end; + nomatch -> + S; + _ -> + erlang:error(bad_regexp) + end. + +replace_amps(Bin) -> + list_to_binary( + lists:flatmap( + fun($&) -> "\\&"; + ($\\) -> "\\\\"; + (Chr) -> [Chr] + end, binary_to_list(Bin))). |