ipa_proto: Implement ccm response with variable options

This commit allows configuration of the ccm protocol options used when
setting up an ipa connection with an external entity. The options
record is kept alongside the socket in the socket-owning process loop,
and used to fill the values in the ccm identity response. If
additional CCM state were needed in the future this commit could be
extended to keep generic state, with the options only representing one
piece of the overall state.

Change-Id: I3f67095f33f1ff826ad04dad72990bf79617149a

include/ipa.hrl

@@ -0,0 +1,32 @@
+% (C) 2020 by Matt Johnson <matt9j@cs.washington.edu>
+%
+% 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.
+
+-ifndef(IPA).
+-define(IPA, true).
+
+-record(ipa_ccm_options, {serial_number,
+			  unit_id,
+			  mac_address,
+			  location,
+			  unit_type,
+			  equipment_version,
+			  sw_version,
+			  unit_name
+			 }).
+
+-endif.

src/ipa_proto.erl

@@ -23,6 +23,8 @@
 -author('Harald Welte <laforge@gnumonks.org>').
 -compile(export_all).
 
+-include("ipa.hrl").
+
 -define(TIMEOUT, 1000).
 -define(IPA_SOCKOPTS, [binary, {packet, 0}, {reuseaddr, true}, {active, false}]).
 
@@ -91,6 +93,10 @@ unregister_stream(Socket, StreamID) ->
 controlling_process(Socket, StreamID, NewPid) ->
 	call_sync_sock(Socket, {ipa_ctrl_proc, Socket, StreamID, NewPid}).
 
+% Set the metadata required for the ipa CCM sub-protocol.
+set_ccm_options(Socket, CcmOptions) ->
+	call_sync_sock(Socket, {ipa_set_ccm_options, Socket, CcmOptions}).
+
 % unblock the socket from further processing
 unblock(Socket) ->
 	send_ccm_id_get(Socket),
@@ -113,6 +119,11 @@ request({ipa_ctrl_proc, Socket, StreamID, NewPid}) ->
 	[IpaSock] = ets:lookup(ipa_sockets, Socket),
 	ets:delete(IpaSock#ipa_socket.streamTbl, {Socket, StreamID}),
 	ets:insert_new(IpaSock#ipa_socket.streamTbl, {{Socket, StreamID}, NewPid});
+% server-side handler for set_ccm_options()
+% set ccm protocol metadata options reported with connection setup.
+request({ipa_set_ccm_options, Socket, CcmOptions}) ->
+	io:format("Setting ccm options for socket ~p to ~p~n", [Socket, CcmOptions]),
+	{ccm_options, CcmOptions};
 % server-side handler for unblock()
 request({ipa_unblock, Socket}) ->
 	io:format("Unblocking socket ~p~n", [Socket]),
@@ -167,20 +178,20 @@ try_encode(StreamID, Data) ->
 	end.
 
 % process (split + deliver) an incoming IPA message
-process_rx_ipa_msg(_S, _StreamMap, <<>>) ->
+process_rx_ipa_msg(_S, _StreamMap, _, <<>>) ->
 	ok;
-process_rx_ipa_msg(S, StreamMap, Data) ->
+process_rx_ipa_msg(S, StreamMap, CcmOptions, Data) ->
 	{StreamID, PayloadBin, Trailer} = split_ipa_msg(Data),
 	case StreamID of
 		?IPAC_PROTO_CCM ->
-			process_rx_ccm_msg(S, StreamID, PayloadBin);
+			process_rx_ccm_msg(S, StreamID, CcmOptions, PayloadBin);
 		?IPAC_PROTO_OSMO ->
 			<<ExtStreamID:8, PayloadExt/binary>> = PayloadBin,
 			deliver_rx_ipa_msg(S, {osmo, ExtStreamID}, StreamMap, PayloadExt);
 		_ ->
 			deliver_rx_ipa_msg(S, StreamID, StreamMap, PayloadBin)
 	end,
-	process_rx_ipa_msg(S, StreamMap, Trailer).
+	process_rx_ipa_msg(S, StreamMap, CcmOptions, Trailer).
 
 send_close_signal([]) ->
 	ok;
@@ -237,22 +248,29 @@ init_sock(Socket, CallingPid) ->
 	StreamMap = ets:new(stream_map, [set]),
 	ets:insert(ipa_sockets, #ipa_socket{socket=Socket, ipaPid=self(), streamTbl=StreamMap}),
 	CallingPid ! {ipa_init_sock_done, Socket},
-	loop(Socket, StreamMap).
+	loop(Socket, StreamMap, #ipa_ccm_options{}).
 
-loop(S, StreamMap) ->
+loop(S, StreamMap, CcmOptions) ->
 	receive
 		{request, From, Request} ->
-			Reply = ipa_proto:request(Request),
+			case ipa_proto:request(Request) of
+				{ccm_options, NewCcmOptions} ->
+					NextCcmOptions = NewCcmOptions,
+					Reply = ok;
+				EmbeddedReply ->
+					NextCcmOptions = CcmOptions,
+					Reply = EmbeddedReply
+			end,
 			ipa_proto:reply(From, Reply),
-			ipa_proto:loop(S, StreamMap);
+			ipa_proto:loop(S, StreamMap, NextCcmOptions);
 		{ipa_send, S, StreamId, Data} ->
 			send(S, StreamId, Data),
-			ipa_proto:loop(S, StreamMap);
+			ipa_proto:loop(S, StreamMap, CcmOptions);
 		{tcp, S, Data} ->
 			% process incoming IPA message and mark socket active once more
-			ipa_proto:process_rx_ipa_msg(S, StreamMap, Data),
+			ipa_proto:process_rx_ipa_msg(S, StreamMap, CcmOptions, Data),
 			inet:setopts(S, [{active, once}]),
-			ipa_proto:loop(S, StreamMap);
+			ipa_proto:loop(S, StreamMap, CcmOptions);
 		{tcp_closed, S} ->
 			io:format("Socket ~w closed [~w]~n", [S,self()]),
 			ipa_proto:process_tcp_closed(S, StreamMap),
@@ -261,26 +279,42 @@ loop(S, StreamMap) ->
 	end.
 
 % Respond with PONG to PING
-process_ccm_msg(Socket, StreamID, ping, _) ->
+process_ccm_msg(Socket, StreamID, _, ping, _) ->
 	io:format("Socket ~p Stream ~p: PING -> PONG~n", [Socket, StreamID]),
 	send(Socket, StreamID, <<?IPAC_MSGT_PONG>>);
 % Simply respond to ID_ACK with ID_ACK
-process_ccm_msg(Socket, StreamID, id_ack, _) ->
+process_ccm_msg(Socket, StreamID, _, id_ack, _) ->
 	io:format("Socket ~p Stream ~p: ID_ACK -> ID_ACK~n", [Socket, StreamID]),
 	send(Socket, StreamID, <<?IPAC_MSGT_ID_ACK>>);
 % Simply respond to ID_RESP with ID_ACK
-process_ccm_msg(Socket, StreamID, id_resp, _) ->
+process_ccm_msg(Socket, StreamID, _, id_resp, _) ->
 	io:format("Socket ~p Stream ~p: ID_RESP -> ID_ACK~n", [Socket, StreamID]),
 	send(Socket, StreamID, <<?IPAC_MSGT_ID_ACK>>);
+% Simply respond to ID_GET with ID_RESP
+process_ccm_msg(Socket, StreamID, CcmOptions, id_req, _) ->
+	io:format("Socket ~p Stream ~p: ID_GET -> ID_RESP~n", [Socket, StreamID]),
+	CcmBin = ipa_proto_ccm:encode(
+		{id_resp,
+		 [{string,serial_nr,CcmOptions#ipa_ccm_options.serial_number},
+		  {string,unit_id,CcmOptions#ipa_ccm_options.unit_id},
+		  {string,mac_address,CcmOptions#ipa_ccm_options.mac_address},
+		  {string,location,CcmOptions#ipa_ccm_options.location},
+		  {string,unit_type,CcmOptions#ipa_ccm_options.unit_type},
+		  {string,equip_vers,CcmOptions#ipa_ccm_options.equipment_version},
+		  {string,sw_version,CcmOptions#ipa_ccm_options.sw_version},
+		  {string,unit_name,CcmOptions#ipa_ccm_options.unit_name}
+		 ]}),
+	send(Socket, StreamID, CcmBin);
+
 % Default message handler for unknown messages
-process_ccm_msg(Socket, StreamID, MsgType, Opts) ->
+process_ccm_msg(Socket, StreamID, _, MsgType, Opts) ->
 	io:format("Socket ~p Stream ~p: Unknown CCM message type ~p Opts ~p~n",
 		  [Socket, StreamID, MsgType, Opts]).
 
 % process an incoming CCM message (Stream ID 254)
-process_rx_ccm_msg(Socket, StreamID, PayloadBin) ->
+process_rx_ccm_msg(Socket, StreamID, CcmOptions, PayloadBin) ->
 	{MsgType, Opts} = ipa_proto_ccm:decode(PayloadBin),
-	process_ccm_msg(Socket, StreamID, MsgType, Opts).
+	process_ccm_msg(Socket, StreamID, CcmOptions, MsgType, Opts).
 
 send_ccm_id_get(Socket) ->
 	send(Socket, ?IPAC_PROTO_CCM, <<?IPAC_MSGT_ID_GET>>).