%%%----------------------------------------------------------------------
%%% File : ejabberd_http.erl
%%% Author : Paweł Chmielowski <pawel@process-one.net>
%%% Purpose :
%%% Created : 27 Nov 2018 by Paweł Chmielowski <pawel@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(proxy_protocol).
-author("pawel@process-one.net").
%% API
-export([decode/3]).
decode(SockMod, Socket, Timeout) ->
V = SockMod:recv(Socket, 6, Timeout),
case V of
{ok, <<"PROXY ">>} ->
decode_v1(SockMod, Socket, Timeout);
{ok, <<16#0d, 16#0a, 16#0d, 16#0a, 16#00, 16#0d>>} ->
decode_v2(SockMod, Socket, Timeout);
_ ->
{error, eproto}
end.
decode_v1(SockMod, Socket, Timeout) ->
case read_until_rn(SockMod, Socket, <<>>, false, Timeout) of
{error, _} = Err ->
Err;
Val ->
case binary:split(Val, <<" ">>, [global]) of
[<<"TCP4">>, SAddr, DAddr, SPort, DPort] ->
try {inet_parse:ipv4strict_address(binary_to_list(SAddr)),
inet_parse:ipv4strict_address(binary_to_list(DAddr)),
binary_to_integer(SPort),
binary_to_integer(DPort)}
of
{{ok, DA}, {ok, SA}, DP, SP} ->
{{SA, SP}, {DA, DP}};
_ ->
{error, eproto}
catch
error:badarg ->
{error, eproto}
end;
[<<"TCP6">>, SAddr, DAddr, SPort, DPort] ->
try {inet_parse:ipv6strict_address(binary_to_list(SAddr)),
inet_parse:ipv6strict_address(binary_to_list(DAddr)),
binary_to_integer(SPort),
binary_to_integer(DPort)}
of
{{ok, DA}, {ok, SA}, DP, SP} ->
{{SA, SP}, {DA, DP}};
_ ->
{error, eproto}
catch
error:badarg ->
{error, eproto}
end;
[<<"UNKNOWN">> | _] ->
{undefined, undefined}
end
end.
decode_v2(SockMod, Socket, Timeout) ->
case SockMod:recv(Socket, 10, Timeout) of
{error, _} = Err ->
Err;
{ok, <<16#0a, 16#51, 16#55, 16#49, 16#54, 16#0a,
2:4, Command:4, Transport:8, AddrLen:16/big-unsigned-integer>>} ->
case SockMod:recv(Socket, AddrLen, Timeout) of
{error, _} = Err ->
Err;
{ok, Data} ->
case Command of
0 ->
case {inet:sockname(Socket), inet:peername(Socket)} of
{{ok, SA}, {ok, DA}} ->
{SA, DA};
{{error, _} = E, _} ->
E;
{_, {error, _} = E} ->
E
end;
1 ->
case Transport of
% UNSPEC or UNIX
V when V == 0; V == 16#31; V == 16#32 ->
{{unknown, unknown}, {unknown, unknown}};
% IPV4 over TCP or UDP
V when V == 16#11; V == 16#12 ->
case Data of
<<D1:8, D2:8, D3:8, D4:8,
S1:8, S2:8, S3:8, S4:8,
DP:16/big-unsigned-integer,
SP:16/big-unsigned-integer,
_/binary>> ->
{{{S1, S2, S3, S4}, SP},
{{D1, D2, D3, D4}, DP}};
_ ->
{error, eproto}
end;
% IPV6 over TCP or UDP
V when V == 16#21; V == 16#22 ->
case Data of
<<D1:16/big-unsigned-integer,
D2:16/big-unsigned-integer,
D3:16/big-unsigned-integer,
D4:16/big-unsigned-integer,
D5:16/big-unsigned-integer,
D6:16/big-unsigned-integer,
D7:16/big-unsigned-integer,
D8:16/big-unsigned-integer,
S1:16/big-unsigned-integer,
S2:16/big-unsigned-integer,
S3:16/big-unsigned-integer,
S4:16/big-unsigned-integer,
S5:16/big-unsigned-integer,
S6:16/big-unsigned-integer,
S7:16/big-unsigned-integer,
S8:16/big-unsigned-integer,
DP:16/big-unsigned-integer,
SP:16/big-unsigned-integer,
_/binary>> ->
{{{S1, S2, S3, S4, S5, S6, S7, S8}, SP},
{{D1, D2, D3, D4, D5, D6, D7, D8}, DP}};
_ ->
{error, eproto}
end
end;
_ ->
{error, eproto}
end
end;
<<16#0a, 16#51, 16#55, 16#49, 16#54, 16#0a, _/binary>> ->
{error, eproto};
_ ->
{error, eproto}
end.
read_until_rn(_SockMod, _Socket, Data, _, _) when size(Data) > 107 ->
{error, eproto};
read_until_rn(SockMod, Socket, Data, true, Timeout) ->
case SockMod:recv(Socket, 1, Timeout) of
{ok, <<"\n">>} ->
Data;
{ok, <<"\r">>} ->
read_until_rn(SockMod, Socket, <<Data/binary, "\r">>,
true, Timeout);
{ok, Other} ->
read_until_rn(SockMod, Socket, <<Data/binary, "\r", Other/binary>>,
false, Timeout);
{error, _} = Err ->
Err
end;
read_until_rn(SockMod, Socket, Data, false, Timeout) ->
case SockMod:recv(Socket, 2, Timeout) of
{ok, <<"\r\n">>} ->
Data;
{ok, <<Byte:8, "\r">>} ->
read_until_rn(SockMod, Socket, <<Data/binary, Byte:8>>,
true, Timeout);
{ok, Other} ->
read_until_rn(SockMod, Socket, <<Data/binary, Other/binary>>,
false, Timeout);
{error, _} = Err ->
Err
end.
