Initial (untested) version of the full UDP<->patching<->IPA chain

1 files changed, 62 insertions, 0 deletions

diff --git a/src/osmo_map_masq.erl b/src/osmo_map_masq.erl
new file mode 100644
index 0000000..7034888
--- /dev/null
+++ b/src/osmo_map_masq.erl
@@ -0,0 +1,62 @@
+% MAP masquerading application
+
+% (C) 2010 by Harald Welte <laforge@gnumonks.org>
+% (C) 2010 by On-Waves
+%
+% All Rights Reserved
+%
+% 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(osmo_map_masq).
+-author('Harald Welte <laforge@gnumonks.org>').
+-export([init/4]).
+
+-record(loop_data,
+        {udpSocket, udpSrvPort, udpRxAddr, udpRxPort,
+	 ipaSocket, ipaStreamID, ipaDstAddr, ipaDstPort}).
+	
+
+init(UdpServerPort, IpaDstAddr, IpaDstPort, IpaStreamID) ->
+	{ok, UdpSock} = gen_udp:open(UdpServerPort, [binary, inet]),
+	{ok, TcpSock} = ipa_proto:connect(IpaDstAddr, IpaDstPort, []),
+	% FIXME: result evaluation
+	ipa_proto:register_stream(TcpSock, IpaStreamID, self()),
+	loop(#loop_data{udpSocket=UdpSock, udpSrvPort=UdpServerPort,
+			ipaSocket=TcpSock, ipaStreamID=IpaStreamID, ipaDstAddr=IpaDstAddr, ipaDstPort=IpaDstPort}).
+
+
+loop(#loop_data{}=LoopData) ->
+	io:format("osmo_masq_loop~n"),
+	receive 
+		{udp, S, ClientIP, ClientPort, Packet} when S =:= LoopData#loop_data.udpSocket ->
+			io:format("UDP received from ~p:~p ==> ~p~n", [ClientIP, ClientPort, Packet]),
+			{ok, SccpHdr, SccpPayload} = sccp_proto:split_udt_sync(Packet),
+			{ok, NewSccpPayload} = tcap_map_patch:handle_tcap_msg(binary_to_list(SccpPayload)),
+			{ok, NewSccpBinary} = sccp_proto:wrap_udt_sync(SccpHdr, list_to_binary(NewSccpPayload)),
+			ipa_proto:send(LoopData#loop_data.ipaSocket, LoopData#loop_data.ipaStreamID, NewSccpBinary),
+			% loop using the (new?) UDP socket Rx IP and Port number
+			loop(LoopData#loop_data{udpRxAddr=ClientIP, udpRxPort=ClientPort});
+		{ipa, S, StreamID, Message} when S =:= LoopData#loop_data.ipaSocket,
+						  StreamID =:= LoopData#loop_data.ipaStreamID ->
+			io:format("IPA received (Stream ~p)~n", [LoopData#loop_data.ipaStreamID]),
+			{ok, SccpHdr, SccpPayload} = sccp_proto:split_udt_sync(Message),
+			{ok, NewSccpPayload} = tcap_map_patch:handle_tcap_msg(binary_to_list(SccpPayload)),
+			{ok, NewSccpBinary} = sccp_proto:wrap_udt_sync(SccpHdr, list_to_binary(NewSccpPayload)),
+			gen_udp:send(LoopData#loop_data.udpSocket, LoopData#loop_data.udpRxAddr,
+				     LoopData#loop_data.udpRxPort, NewSccpBinary),
+			loop(LoopData);
+		{ipa_closed, S} when S =:= LoopData#loop_data.ipaSocket ->
+			io:format("IPA socket was closed, stopping process~n")
+	end.