summaryrefslogtreecommitdiffstats
path: root/library/GSUP_Emulation.ttcn
blob: 86859baa8bdfe0f4f75aae076a66938c9de8dfad (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
module GSUP_Emulation {

/* GSUP Emulation, runs on top of IPA_Emulation.  It multiplexes/demultiplexes
 * the individual calls, so there can be separate TTCN-3 components handling
 * each of the calls
 *
 * The GSUP_Emulation.main() function processes GSUP primitives from the IPA/GSUP
 * socket via the IPA_Emulation, and dispatches them to the per-connection components.
 *
 * Outbound GSUP connections are initiated by sending a FIXME primitive
 * to the component running the GSUP_Emulation.main() function.
 *
 * For each new inbound connections, the GsupOps.create_cb() is called.  It can create
 * or resolve a TTCN-3 component, and returns a component reference to which that inbound
 * connection is routed/dispatched.
 *
 * If a pre-existing component wants to register to handle a future inbound call, it can
 * do so by registering an "expect" with the expected destination phone number.  This is e.g. useful
 * if you are simulating BSC + HUL, and first trigger a connection from BSC side in a
 * component which then subsequently should also handle the GSUP emulation.
 *
 * (C) 2018 by Harald Welte <laforge@gnumonks.org>
 * All rights reserved.
 *
 * Released under the terms of GNU General Public License, Version 2 or
 * (at your option) any later version.
 */


import from Osmocom_Types all;
import from GSUP_Types all;
import from IPA_Emulation all;

/* General "base class" component definition, of which specific implementations
 * derive themselves by means of the "extends" feature */
type component GSUP_ConnHdlr {
	/* ports towards GSUP Emulator core / call dispatchar */
	port GSUP_Conn_PT GSUP;
	port GSUPEM_PROC_PT GSUP_PROC;
}

/* port between individual per-connection components and this dispatcher */
type port GSUP_Conn_PT message {
	inout GSUP_PDU;
} with { extension "internal" };


/* represents a single GSUP call */
type record ConnectionData {
	/* reference to the instance of the per-connection component */
	GSUP_ConnHdlr	comp_ref,
	charstring	imsi
}

type component GSUP_Emulation_CT {
	/* UNIX DOMAIN socket on the bottom side, using primitives */
	port IPA_GSUP_PT GSUP;
	/* GSUP port to the per-connection clients */
	port GSUP_Conn_PT GSUP_CLIENT;

	/* use 16 as this is also the number of SCCP connections that SCCP_Emulation can handle */
	var ConnectionData GsupImsiTable[16];

	/* pending expected incoming connections */
	var ExpectData GsupExpectTable[8];
	/* procedure based port to register for incoming connections */
	port GSUPEM_PROC_PT GSUP_PROC;
};

private function f_imsi_known(charstring imsi)
runs on GSUP_Emulation_CT return boolean {
	var integer i;
	for (i := 0; i < sizeof(GsupImsiTable); i := i+1) {
		if (GsupImsiTable[i].imsi == imsi) {
			return true;
		}
	}
	return false;
}

private function f_comp_known(GSUP_ConnHdlr client)
runs on GSUP_Emulation_CT return boolean {
	var integer i;
	for (i := 0; i < sizeof(GsupImsiTable); i := i+1) {
		if (GsupImsiTable[i].comp_ref == client) {
			return true;
		}
	}
	return false;
}

/* resolve component reference by connection ID */
private function f_comp_by_imsi(charstring imsi)
runs on GSUP_Emulation_CT return GSUP_ConnHdlr {
	var integer i;
	for (i := 0; i < sizeof(GsupImsiTable); i := i+1) {
		if (GsupImsiTable[i].imsi == imsi) {
			return GsupImsiTable[i].comp_ref;
		}
	}
	setverdict(fail, "GSUP IMSI table not found by IMSI ", imsi);
	mtc.stop;
}

/* resolve connection ID by component reference */
private function f_imsi_by_comp(GSUP_ConnHdlr client)
runs on GSUP_Emulation_CT return charstring {
	for (var integer i := 0; i < sizeof(GsupImsiTable); i := i+1) {
		if (GsupImsiTable[i].comp_ref == client) {
			return GsupImsiTable[i].imsi;
		}
	}
	setverdict(fail, "GSUP IMSI table not found by component ", client);
	mtc.stop;
}

private function f_imsi_table_init()
runs on GSUP_Emulation_CT {
	for (var integer i := 0; i < sizeof(GsupImsiTable); i := i+1) {
		GsupImsiTable[i].comp_ref := null;
		GsupImsiTable[i].imsi := "";
	}
}

private function f_expect_table_init()
runs on GSUP_Emulation_CT {
	for (var integer i := 0; i < sizeof(GsupExpectTable); i := i+1) {
		GsupExpectTable[i].vc_conn := null;
		GsupExpectTable[i].imsi := omit;
	}
}

private function f_imsi_table_add(GSUP_ConnHdlr comp_ref, charstring imsi)
runs on GSUP_Emulation_CT {
	for (var integer i := 0; i < sizeof(GsupImsiTable); i := i+1) {
		if (GsupImsiTable[i].imsi == "") {
			GsupImsiTable[i].comp_ref := comp_ref;
			GsupImsiTable[i].imsi := imsi;
			log("Added IMSI table entry ", i, comp_ref, imsi);
			return;
		}
	}
	testcase.stop("GSUP IMSI table full!");
}

private function f_imsi_table_del(charstring imsi)
runs on GSUP_Emulation_CT {
	for (var integer i := 0; i < sizeof(GsupImsiTable); i := i+1) {
		if (GsupImsiTable[i].imsi == imsi) {
			log("Deleted GSUP IMSI table entry ", i,
			    GsupImsiTable[i].comp_ref, imsi);
			GsupImsiTable[i].imsi := "";
			GsupImsiTable[i].comp_ref := null;
			return
		}
	}
	setverdict(fail, "GSUP IMSI table attempt to delete non-existant ", imsi);
	mtc.stop;
}


/* call-back type, to be provided by specific implementation; called when new SCCP connection
 * arrives */
type function GsupCreateCallback(GSUP_PDU gsup, charstring id)
runs on GSUP_Emulation_CT return GSUP_ConnHdlr;

type record GsupOps {
	GsupCreateCallback create_cb
}

function main(GsupOps ops, charstring id) runs on GSUP_Emulation_CT {

	f_imsi_table_init();
	f_expect_table_init();

	while (true) {
		var GSUP_ConnHdlr vc_conn;
		var GSUP_ConnHdlr vc_hdlr;
		var GSUP_PDU gsup;
		var charstring imsi;

		alt {

		[] GSUP.receive(ASP_IPA_Event:{up_down:=ASP_IPA_EVENT_ID_ACK}) { repeat; }
		[] GSUP.receive(ASP_IPA_Event:{up_down:=ASP_IPA_EVENT_UP}) { repeat; }
		[] GSUP.receive(ASP_IPA_Event:{up_down:=ASP_IPA_EVENT_DOWN}) {
			setverdict(fail, "GSUP Connection Lost");
			mtc.stop;
			}

		/* GSUP -> Client: call related messages */
		[] GSUP.receive(GSUP_PDU:?) -> value gsup {
			imsi := hex2str(gsup.ies[0].val.imsi);

			if (f_imsi_known(imsi)) {
				vc_conn := f_comp_by_imsi(imsi);
				GSUP_CLIENT.send(gsup) to vc_conn;
			} else {
				/* TODO: Only accept this for SETUP.req? */
				vc_conn := ops.create_cb.apply(gsup, id)
				/* store mapping between client components and SCCP connectionId */
				f_imsi_table_add(vc_conn, imsi);
				/* handle user payload */
				GSUP_CLIENT.send(gsup) to vc_conn;
			}
			}

		[] GSUP.receive { repeat; }

		/* Client -> GSUP Socket: Normal message */
		[] GSUP_CLIENT.receive(GSUP_PDU:?) -> value gsup sender vc_conn {
			/* forward to GSUP socket */
			GSUP.send(gsup);
			}


		/* Client -> us: procedure call to register expect */
		[] GSUP_PROC.getcall(GSUPEM_register:{?,?}) -> param(imsi, vc_hdlr) {
			f_create_expect(imsi, vc_hdlr);
			GSUP_PROC.reply(GSUPEM_register:{imsi, vc_hdlr}) to vc_hdlr;
			}

		}
	}
}

/***********************************************************************
 * "Expect" Handling (mapping for expected incoming GSUP calls from IUT)
 ***********************************************************************/

/* data about an expected future incoming connection */
type record ExpectData {
	/* destination number based on which we can match it */
	charstring imsi optional,
	/* component reference for this connection */
	GSUP_ConnHdlr vc_conn
}

/* procedure based port to register for incoming calls */
signature GSUPEM_register(in charstring imsi, in GSUP_ConnHdlr hdlr);

type port GSUPEM_PROC_PT procedure {
	inout GSUPEM_register;
} with { extension "internal" };

/* CreateCallback that can be used as create_cb and will use the expectation table */
function ExpectedCreateCallback(GSUP_PDU gsup, charstring id)
runs on GSUP_Emulation_CT return GSUP_ConnHdlr {
	var GSUP_ConnHdlr ret := null;
	var charstring imsi;
	var integer i;

	imsi := hex2str(gsup.ies[0].val.imsi);

	for (i := 0; i < sizeof(GsupExpectTable); i:= i+1) {
		if (not ispresent(GsupExpectTable[i].imsi)) {
			continue;
		}
		if (imsi == GsupExpectTable[i].imsi) {
			ret := GsupExpectTable[i].vc_conn;
			/* release this entry to be used again */
			GsupExpectTable[i].imsi := omit;
			GsupExpectTable[i].vc_conn := null;
			log("Found GsupExpect[", i, "] for ", imsi, " handled at ", ret);
			/* return the component reference */
			return ret;
		}
	}
	setverdict(fail, "Couldn't find GsupExpect for incoming imsi ", imsi);
	mtc.stop;
	return ret;
}

/* server/emulation side function to create expect */
private function f_create_expect(charstring imsi, GSUP_ConnHdlr hdlr)
runs on GSUP_Emulation_CT {
	var integer i;
	for (i := 0; i < sizeof(GsupExpectTable); i := i+1) {
		if (not ispresent(GsupExpectTable[i].imsi)) {
			GsupExpectTable[i].imsi := imsi;
			GsupExpectTable[i].vc_conn := hdlr;
			log("Created GsupExpect[", i, "] for ", imsi, " to be handled at ", hdlr);
			return;
		}
	}
	testcase.stop("No space left in GsupExpectTable");
}

/* client/conn_hdlr side function to use procedure port to create expect in emulation */
function f_create_gsup_expect(charstring imsi) runs on GSUP_ConnHdlr {
	GSUP_PROC.call(GSUPEM_register:{imsi, self}) {
		[] GSUP_PROC.getreply(GSUPEM_register:{?,?}) {};
	}
}

}