gbproxy: Handle old and new P-TMSI/TLLI

Don't replace the current TLLI immediately, store it in an additional
'assigned_tlli' field and discard the old TLLI when both sides have
used the new one (see GSM 04.08, 4.7.1.5).

Add an Attach Complete message to test and check, whether the related
field of the corresponding tlli_info struct are set as expected
during the local TLLI validation cycle.

Sponsored-by: On-Waves ehf

1 files changed, 53 insertions, 4 deletions

diff --git a/openbsc/tests/gbproxy/gbproxy_test.c b/openbsc/tests/gbproxy/gbproxy_test.c
index 27454a2a9..0d55fb3db 100644
--- a/openbsc/tests/gbproxy/gbproxy_test.c
+++ b/openbsc/tests/gbproxy/gbproxy_test.c
@@ -25,6 +25,7 @@
 #include <osmocom/core/signal.h>
 #include <osmocom/core/rate_ctr.h>
 #include <osmocom/gsm/tlv.h>
+#include <osmocom/gsm/gsm_utils.h>
 #include <osmocom/gprs/gprs_msgb.h>
 #include <osmocom/gprs/gprs_ns.h>
 #include <osmocom/gprs/gprs_bssgp.h>
@@ -124,10 +125,12 @@ static int dump_peers(FILE *stream, int indent, time_t now,
 			} else {
 				snprintf(mi_buf, sizeof(mi_buf), "(none)");
 			}
-			rc = fprintf(stream,
-				     "%*s      TLLI %08x, IMSI %s, AGE %d\n",
-				     indent, "",
-				     tlli_info->tlli, mi_buf, (int)age);
+			fprintf(stream, "%*s      TLLI %08x",
+				     indent, "", tlli_info->tlli);
+			if (tlli_info->assigned_tlli)
+				fprintf(stream, "/%08x", tlli_info->assigned_tlli);
+			rc = fprintf(stream, ", IMSI %s, AGE %d\n",
+				     mi_buf, (int)age);
 			if (rc < 0)
 				return rc;
 		}
@@ -181,6 +184,14 @@ static const unsigned char bssgp_attach_acc[88] = {
 	0xf4, 0xef, 0xe2, 0xb7, 0x00, 0x42, 0x67, 0x9a
 };
 
+/* Base Station Subsystem GPRS Protocol: GSM A-I/F DTAP - Attach Complete */
+static const unsigned char bssgp_attach_complete[] = {
+	0x01, 0xef, 0xe2, 0xb7, 0x00, 0x00, 0x00, 0x04,
+	0x08, 0x88, 0x11, 0x22, 0x33, 0x40, 0x50, 0x60,
+	0x75, 0x30, 0x00, 0x80, 0x0e, 0x00, 0x08, 0x01,
+	0xc0, 0x11, 0x08, 0x03, 0xff, 0xff, 0xff
+};
+
 /* Base Station Subsystem GPRS Protocol: GSM A-I/F DTAP - GMM Information */
 static const unsigned char bssgp_gmm_information[66] = {
 	0x00, 0xef, 0xe2, 0xb7, 0x00, 0x00, 0x50, 0x20,
@@ -970,6 +981,12 @@ static void test_gbproxy_ra_patching()
 	struct  gprs_ra_id rai_unknown =
 		{.mcc = 1, .mnc = 99, .lac = 99, .rac = 96};
 	const char *err_msg = NULL;
+	const uint32_t ptmsi = 0xefe2b700;
+	const uint32_t local_tlli = 0xefe2b700;
+	struct gbproxy_tlli_info *tlli_info;
+	struct gbproxy_peer *peer;
+
+	OSMO_ASSERT(local_tlli == gprs_tmsi2tlli(ptmsi, TLLI_LOCAL));
 
 	bssgp_nsi = nsi;
 	gbcfg.nsi = bssgp_nsi;
@@ -1003,6 +1020,9 @@ static void test_gbproxy_ra_patching()
 	gprs_dump_nsi(nsi);
 	dump_peers(stdout, 0, 0, &gbcfg);
 
+	peer = gbprox_peer_by_nsei(&gbcfg, 0x1000);
+	OSMO_ASSERT(peer != NULL);
+
 	send_bssgp_reset_ack(nsi, &sgsn_peer, 0x1002);
 
 	send_bssgp_suspend(nsi, &bss_peer[0], &rai_bss);
@@ -1025,14 +1045,43 @@ static void test_gbproxy_ra_patching()
 	send_ns_unitdata(nsi, "ATTACH ACCEPT", &sgsn_peer, 0x1002,
 			 bssgp_attach_acc, sizeof(bssgp_attach_acc));
 
+	tlli_info = gbprox_find_tlli(peer, local_tlli);
+	OSMO_ASSERT(tlli_info);
+	OSMO_ASSERT(tlli_info->assigned_tlli == local_tlli);
+	OSMO_ASSERT(tlli_info->tlli != local_tlli);
+	OSMO_ASSERT(!tlli_info->bss_validated);
+	OSMO_ASSERT(!tlli_info->net_validated);
+
+	send_ns_unitdata(nsi, "ATTACH COMPLETE", &bss_peer[0], 0x1002,
+			 bssgp_attach_complete, sizeof(bssgp_attach_complete));
+
+	tlli_info = gbprox_find_tlli(peer, local_tlli);
+	OSMO_ASSERT(tlli_info);
+	OSMO_ASSERT(tlli_info->assigned_tlli == local_tlli);
+	OSMO_ASSERT(tlli_info->tlli != local_tlli);
+	OSMO_ASSERT(tlli_info->bss_validated);
+	OSMO_ASSERT(!tlli_info->net_validated);
+
 	/* Replace APN (1) */
 	send_ns_unitdata(nsi, "ACT PDP CTX REQ (REPLACE APN)",
 			 &bss_peer[0], 0x1002,
 			 bssgp_act_pdp_ctx_req, sizeof(bssgp_act_pdp_ctx_req));
 
+	tlli_info = gbprox_find_tlli(peer, local_tlli);
+	OSMO_ASSERT(tlli_info);
+	OSMO_ASSERT(tlli_info->assigned_tlli == local_tlli);
+	OSMO_ASSERT(tlli_info->tlli != local_tlli);
+	OSMO_ASSERT(tlli_info->bss_validated);
+	OSMO_ASSERT(!tlli_info->net_validated);
+
 	send_ns_unitdata(nsi, "GMM INFO", &sgsn_peer, 0x1002,
 			 bssgp_gmm_information, sizeof(bssgp_gmm_information));
 
+	tlli_info = gbprox_find_tlli(peer, local_tlli);
+	OSMO_ASSERT(tlli_info);
+	OSMO_ASSERT(tlli_info->assigned_tlli == 0);
+	OSMO_ASSERT(tlli_info->tlli == local_tlli);
+
 	/* Replace APN (2) */
 	send_ns_unitdata(nsi, "ACT PDP CTX REQ (REPLACE APN)",
 			 &bss_peer[0], 0x1002,