Initial GSUP Auth handler support

Change-Id: Iad42c74f1c6f35791d3e33c1082e804eb67e861c
---
A src/auth_handler.erl
M src/gsup_server.erl
M src/osmo_epdg_sup.erl
3 files changed, 74 insertions(+), 3 deletions(-)

diff --git a/src/auth_handler.erl b/src/auth_handler.erl
new file mode 100644
index 0000000..83e8aaf
--- /dev/null
+++ b/src/auth_handler.erl
@@ -0,0 +1,58 @@
+-module(auth_handler).
+-behaviour(gen_server).
+
+-include_lib("osmo_gsup/include/gsup_protocol.hrl").
+-include_lib("diameter_3gpp_ts29_273_swx.hrl").
+
+-record(auth_state, {
+	table_id % ets table id
+}).
+
+-export([start_link/0]).
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2]).
+-export([code_change/3, terminate/2]).
+
+-export[(auth_request/1)].
+
+-define(SERVER, ?MODULE).
+
+% The ets table contains only IMSIs
+
+start_link() ->
+	gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
+
+init([]) ->
+	TableId = ets:new(auth_req, [bag, named_table]),
+	{ok, #auth_state{table_id = TableId}}.
+
+
+auth_request(Imsi) ->
+	gen_server:call(?SERVER, {epdg_auth_req, Imsi}).
+
+handle_call({epdg_auth_req, Imsi}, From, State) ->
+	% request the diameter code for a tuple
+	CKey = [],
+	IntegrityKey = [],
+	Result = epdg_diameter_swx:multimedia_auth_request(Imsi, 1, "EAP-AKA", 1, CKey, IntegrityKey),
+	case Result of
+		{ok, Mar} -> {reply, {ok, Mar}, State};
+		{error, Err} -> {reply, {error, Err}, State};
+		{_, _} -> {reply, {error, unknown}, State}
+	end.
+
+handle_cast(Info, S) ->
+	error_logger:error_report(["unknown handle_cast", {module, ?MODULE}, {info, Info}, {state, S}]),
+	{noreply, S}.
+handle_info(Info, S) ->
+	error_logger:error_report(["unknown handle_info", {module, ?MODULE}, {info, Info}, {state, S}]),
+	{noreply, S}.
+
+
+stop() ->
+	gen_server:call(?MODULE, stop).
+
+code_change(_OldVsn, State, _Extra) ->
+	{ok, State}.
+
+terminate(Reason, _S) ->
+	lager:info("terminating ~p with reason ~p~n", [?MODULE, Reason]).
diff --git a/src/gsup_server.erl b/src/gsup_server.erl
index e25e681..26af3b4 100644
--- a/src/gsup_server.erl
+++ b/src/gsup_server.erl
@@ -140,8 +140,7 @@
 
 % send auth info / requesting authentication tuples
 handle_info({ipa, Socket, ?IPAC_PROTO_EXT_GSUP, GsupMsgRx = #{message_type := send_auth_info_req, imsi := Imsi}}, S) ->
-	Auth = {error, 'not_implemented_yet!'},
-	%Auth = auth_handler:auth_request(Imsi),
+	Auth = auth_handler:auth_request(Imsi),
 	case Auth of
 		{ok, Mar} ->	SipAuthTuples = Mar#'MAA'.'SIP-Auth-Data-Item',
 				% AuthTuples = dia_sip2gsup(SipAuthTuples),
diff --git a/src/osmo_epdg_sup.erl b/src/osmo_epdg_sup.erl
index d5b0e6e..a523a7f 100644
--- a/src/osmo_epdg_sup.erl
+++ b/src/osmo_epdg_sup.erl
@@ -19,4 +19,9 @@
 		      5000,
 		      worker,
 		      [gsup_server]},
-	{ok, { {one_for_all, 5, 10}, [DiaServer, GsupServer]} }.
+	AuthHandler = {auth_handler, {auth_handler, start_link, []},
+		       permanent,
+		       5000,
+		       worker,
+		       [auth_handler]},
+	{ok, { {one_for_all, 5, 10}, [DiaServer, GsupServer, AuthHandler]} }.

