Add support for proxy protocol

This add support for version 1 and 2 of protocol specified in
http://www.haproxy.org/download/1.8/doc/proxy-protocol.txt

To enable it you need add option use_proxy_protocol: true to listener.

1 files changed, 182 insertions, 0 deletions

diff --git a/src/proxy_protocol.erl b/src/proxy_protocol.erl
new file mode 100644
index 000000000..232f9cca3
--- /dev/null
+++ b/src/proxy_protocol.erl
@@ -0,0 +1,182 @@
+%%%----------------------------------------------------------------------
+%%% 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) 2002-2018   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>> ->
+					    {{{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>> ->
+					    {{{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.