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Diffstat (limited to 'src/ejabberd_idna.erl')
| -rw-r--r-- | src/ejabberd_idna.erl | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/src/ejabberd_idna.erl b/src/ejabberd_idna.erl new file mode 100644 index 000000000..bee3f87ed --- /dev/null +++ b/src/ejabberd_idna.erl @@ -0,0 +1,224 @@ +%%%---------------------------------------------------------------------- +%%% File : ejabberd_idna.erl +%%% Author : Alexey Shchepin <alexey@process-one.net> +%%% Purpose : Support for IDNA (RFC3490) +%%% Created : 10 Apr 2004 by Alexey Shchepin <alexey@process-one.net> +%%% +%%% +%%% ejabberd, Copyright (C) 2002-2015 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_idna). + +-author('alexey@process-one.net'). + +-export([domain_utf8_to_ascii/1, + domain_ucs2_to_ascii/1, + utf8_to_ucs2/1]). + +-ifdef(TEST). +-include_lib("eunit/include/eunit.hrl"). +-endif. + +-spec domain_utf8_to_ascii(binary()) -> false | binary(). + +domain_utf8_to_ascii(Domain) -> + domain_ucs2_to_ascii(utf8_to_ucs2(Domain)). + +utf8_to_ucs2(S) -> + utf8_to_ucs2(binary_to_list(S), ""). + +utf8_to_ucs2([], R) -> lists:reverse(R); +utf8_to_ucs2([C | S], R) when C < 128 -> + utf8_to_ucs2(S, [C | R]); +utf8_to_ucs2([C1, C2 | S], R) when C1 < 224 -> + utf8_to_ucs2(S, [C1 band 31 bsl 6 bor C2 band 63 | R]); +utf8_to_ucs2([C1, C2, C3 | S], R) when C1 < 240 -> + utf8_to_ucs2(S, + [C1 band 15 bsl 12 bor (C2 band 63 bsl 6) bor C3 band 63 + | R]). + +-spec domain_ucs2_to_ascii(list()) -> false | binary(). + +domain_ucs2_to_ascii(Domain) -> + case catch domain_ucs2_to_ascii1(Domain) of + {'EXIT', _Reason} -> false; + Res -> iolist_to_binary(Res) + end. + +domain_ucs2_to_ascii1(Domain) -> + Parts = string:tokens(Domain, + [46, 12290, 65294, 65377]), + ASCIIParts = lists:map(fun (P) -> to_ascii(P) end, + Parts), + string:strip(lists:flatmap(fun (P) -> [$. | P] end, + ASCIIParts), + left, $.). + +%% Domain names are already nameprep'ed in ejabberd, so we skiping this step +to_ascii(Name) -> + false = lists:any(fun (C) + when (0 =< C) and (C =< 44) or + (46 =< C) and (C =< 47) + or (58 =< C) and (C =< 64) + or (91 =< C) and (C =< 96) + or (123 =< C) and (C =< 127) -> + true; + (_) -> false + end, + Name), + case Name of + [H | _] when H /= $- -> true = lists:last(Name) /= $- + end, + ASCIIName = case lists:any(fun (C) -> C > 127 end, Name) + of + true -> + true = case Name of + "xn--" ++ _ -> false; + _ -> true + end, + "xn--" ++ punycode_encode(Name); + false -> Name + end, + L = length(ASCIIName), + true = (1 =< L) and (L =< 63), + ASCIIName. + +%%% PUNYCODE (RFC3492) + +-define(BASE, 36). + +-define(TMIN, 1). + +-define(TMAX, 26). + +-define(SKEW, 38). + +-define(DAMP, 700). + +-define(INITIAL_BIAS, 72). + +-define(INITIAL_N, 128). + +punycode_encode(Input) -> + N = (?INITIAL_N), + Delta = 0, + Bias = (?INITIAL_BIAS), + Basic = lists:filter(fun (C) -> C =< 127 end, Input), + NonBasic = lists:filter(fun (C) -> C > 127 end, Input), + L = length(Input), + B = length(Basic), + SNonBasic = lists:usort(NonBasic), + Output1 = if B > 0 -> Basic ++ "-"; + true -> "" + end, + Output2 = punycode_encode1(Input, SNonBasic, B, B, L, N, + Delta, Bias, ""), + Output1 ++ Output2. + +punycode_encode1(Input, [M | SNonBasic], B, H, L, N, + Delta, Bias, Out) + when H < L -> + Delta1 = Delta + (M - N) * (H + 1), + % let n = m + {NewDelta, NewBias, NewH, NewOut} = lists:foldl(fun (C, + {ADelta, ABias, AH, + AOut}) -> + if C < M -> + {ADelta + 1, + ABias, AH, + AOut}; + C == M -> + NewOut = + punycode_encode_delta(ADelta, + ABias, + AOut), + NewBias = + adapt(ADelta, + H + + 1, + H + == + B), + {0, NewBias, + AH + 1, + NewOut}; + true -> + {ADelta, + ABias, AH, + AOut} + end + end, + {Delta1, Bias, H, Out}, + Input), + punycode_encode1(Input, SNonBasic, B, NewH, L, M + 1, + NewDelta + 1, NewBias, NewOut); +punycode_encode1(_Input, _SNonBasic, _B, _H, _L, _N, + _Delta, _Bias, Out) -> + lists:reverse(Out). + +punycode_encode_delta(Delta, Bias, Out) -> + punycode_encode_delta(Delta, Bias, Out, ?BASE). + +punycode_encode_delta(Delta, Bias, Out, K) -> + T = if K =< Bias -> ?TMIN; + K >= Bias + (?TMAX) -> ?TMAX; + true -> K - Bias + end, + if Delta < T -> [codepoint(Delta) | Out]; + true -> + C = T + (Delta - T) rem ((?BASE) - T), + punycode_encode_delta((Delta - T) div ((?BASE) - T), + Bias, [codepoint(C) | Out], K + (?BASE)) + end. + +adapt(Delta, NumPoints, FirstTime) -> + Delta1 = if FirstTime -> Delta div (?DAMP); + true -> Delta div 2 + end, + Delta2 = Delta1 + Delta1 div NumPoints, + adapt1(Delta2, 0). + +adapt1(Delta, K) -> + if Delta > ((?BASE) - (?TMIN)) * (?TMAX) div 2 -> + adapt1(Delta div ((?BASE) - (?TMIN)), K + (?BASE)); + true -> + K + + ((?BASE) - (?TMIN) + 1) * Delta div (Delta + (?SKEW)) + end. + +codepoint(C) -> + if (0 =< C) and (C =< 25) -> C + 97; + (26 =< C) and (C =< 35) -> C + 22 + end. + +%%%=================================================================== +%%% Unit tests +%%%=================================================================== +-ifdef(TEST). + +acsii_test() -> + ?assertEqual(<<"test.org">>, domain_utf8_to_ascii(<<"test.org">>)). + +utf8_test() -> + ?assertEqual( + <<"xn--d1acufc.xn--p1ai">>, + domain_utf8_to_ascii( + <<208,180,208,190,208,188,208,181,208,189,46,209,128,209,132>>)). + +-endif. |