implement support for 3-digit MNC with leading zeros

Add 3-digit flags and use the new RAI and LAI API from libosmocore throughout
the code base to be able to handle an MNC < 100 that has three digits (leading
zeros).

The changes to abis_test and gsm0408_test show that this code now handles
3-digit MNC correctly, by not dropping the leading zero as 0xf in the encoded
PLMN.

Re-implement CTRL commands 'mcc', 'mnc' and 'mcc-mnc-apply' to preserve the
presence of the third digit of the MNC. Always reply with all leading zeros.
Adjust the expected results in ctrl_test_runner.py, to show that it works.

In VTY and CTRL, the parsing of MCC and MNC is inherently made stricter by use
of osmo_{mcc,mnc}_from_str() -- they will no longer allow surplus characters
and detect errno returned by strtol() (in contrast to atoi()).

Depends: Id2240f7f518494c9df6c8bda52c0d5092f90f221 (libosmocore),
	 Ib7176b1d65a03b76f41f94bc9d3293a8a07d24c6 (libosmocore),
	 I020a4f11791c61742a3d795f782805f7b7e8733e (libosmocore)
Change-Id: I8e722103344186fde118b26d8353db95a4581daa

13 files changed, 183 insertions, 133 deletions

diff --git a/src/libbsc/bsc_ctrl_commands.c b/src/libbsc/bsc_ctrl_commands.c
index 41d236126..64f458920 100644
--- a/src/libbsc/bsc_ctrl_commands.c
+++ b/src/libbsc/bsc_ctrl_commands.c
@@ -22,6 +22,7 @@
 #include <time.h>
 
 #include <osmocom/ctrl/control_cmd.h>
+#include <osmocom/gsm/gsm48.h>
 #include <osmocom/bsc/ipaccess.h>
 #include <osmocom/bsc/gsm_data.h>
 #include <osmocom/bsc/abis_nm.h>
@@ -30,8 +31,61 @@
 #include <osmocom/bsc/osmo_bsc_rf.h>
 #include <osmocom/bsc/bsc_msc_data.h>
 
-CTRL_CMD_DEFINE_RANGE(net_mnc, "mnc", struct gsm_network, network_code, 0, 999);
-CTRL_CMD_DEFINE_RANGE(net_mcc, "mcc", struct gsm_network, country_code, 1, 999);
+CTRL_CMD_DEFINE(net_mcc, "mcc");
+static int get_net_mcc(struct ctrl_cmd *cmd, void *_data)
+{
+	struct gsm_network *net = cmd->node;
+	cmd->reply = talloc_asprintf(cmd, "%s", osmo_mcc_name(net->plmn.mcc));
+	if (!cmd->reply) {
+		cmd->reply = "OOM";
+		return CTRL_CMD_ERROR;
+	}
+	return CTRL_CMD_REPLY;
+}
+static int set_net_mcc(struct ctrl_cmd *cmd, void *_data)
+{
+	struct gsm_network *net = cmd->node;
+	uint16_t mcc;
+	if (osmo_mcc_from_str(cmd->value, &mcc))
+		return -1;
+	net->plmn.mcc = mcc;
+	return get_net_mcc(cmd, _data);
+}
+static int verify_net_mcc(struct ctrl_cmd *cmd, const char *value, void *_data)
+{
+	if (osmo_mcc_from_str(value, NULL))
+		return -1;
+	return 0;
+}
+
+CTRL_CMD_DEFINE(net_mnc, "mnc");
+static int get_net_mnc(struct ctrl_cmd *cmd, void *_data)
+{
+	struct gsm_network *net = cmd->node;
+	cmd->reply = talloc_asprintf(cmd, "%s", osmo_mnc_name(net->plmn.mnc, net->plmn.mnc_3_digits));
+	if (!cmd->reply) {
+		cmd->reply = "OOM";
+		return CTRL_CMD_ERROR;
+	}
+	return CTRL_CMD_REPLY;
+}
+static int set_net_mnc(struct ctrl_cmd *cmd, void *_data)
+{
+	struct gsm_network *net = cmd->node;
+	struct osmo_plmn_id plmn = net->plmn;
+	if (osmo_mnc_from_str(cmd->value, &plmn.mnc, &plmn.mnc_3_digits)) {
+		cmd->reply = "Error while decoding MNC";
+		return CTRL_CMD_ERROR;
+	}
+	net->plmn = plmn;
+	return get_net_mnc(cmd, _data);
+}
+static int verify_net_mnc(struct ctrl_cmd *cmd, const char *value, void *_data)
+{
+	if (osmo_mnc_from_str(value, NULL, NULL))
+		return -1;
+	return 0;
+}
 
 static int set_net_apply_config(struct ctrl_cmd *cmd, void *data)
 {
@@ -64,6 +118,7 @@ CTRL_CMD_DEFINE_WO_NOVRF(net_apply_config, "apply-configuration");
 static int verify_net_mcc_mnc_apply(struct ctrl_cmd *cmd, const char *value, void *d)
 {
 	char *tmp, *saveptr, *mcc, *mnc;
+	int rc = 0;
 
 	tmp = talloc_strdup(cmd, value);
 	if (!tmp)
@@ -71,39 +126,45 @@ static int verify_net_mcc_mnc_apply(struct ctrl_cmd *cmd, const char *value, voi
 
 	mcc = strtok_r(tmp, ",", &saveptr);
 	mnc = strtok_r(NULL, ",", &saveptr);
-	talloc_free(tmp);
 
-	if (!mcc || !mnc)
-		return 1;
-	return 0;
+	if (osmo_mcc_from_str(mcc, NULL) || osmo_mnc_from_str(mnc, NULL, NULL))
+		rc = -1;
+
+	talloc_free(tmp);
+	return rc;
 }
 
 static int set_net_mcc_mnc_apply(struct ctrl_cmd *cmd, void *data)
 {
 	struct gsm_network *net = cmd->node;
 	char *tmp, *saveptr, *mcc_str, *mnc_str;
-	int mcc, mnc;
+	struct osmo_plmn_id plmn;
 
 	tmp = talloc_strdup(cmd, cmd->value);
 	if (!tmp)
 		goto oom;
 
-
 	mcc_str = strtok_r(tmp, ",", &saveptr);
 	mnc_str = strtok_r(NULL, ",", &saveptr);
 
-	mcc = atoi(mcc_str);
-	mnc = atoi(mnc_str);
+	if (osmo_mcc_from_str(mcc_str, &plmn.mcc)) {
+		cmd->reply = "Error while decoding MCC";
+		return CTRL_CMD_ERROR;
+	}
+
+	if (osmo_mnc_from_str(mnc_str, &plmn.mnc, &plmn.mnc_3_digits)) {
+		cmd->reply = "Error while decoding MNC";
+		return CTRL_CMD_ERROR;
+	}
 
 	talloc_free(tmp);
 
-	if (net->network_code == mnc && net->country_code == mcc) {
+	if (!osmo_plmn_cmp(&net->plmn, &plmn)) {
 		cmd->reply = "Nothing changed";
 		return CTRL_CMD_REPLY;
 	}
 
-	net->network_code = mnc;
-	net->country_code = mcc;
+	net->plmn = plmn;
 
 	return set_net_apply_config(cmd, data);
 
diff --git a/src/libbsc/bsc_init.c b/src/libbsc/bsc_init.c
index a2f0504e1..f164533bc 100644
--- a/src/libbsc/bsc_init.c
+++ b/src/libbsc/bsc_init.c
@@ -326,9 +326,10 @@ static void bootstrap_rsl(struct gsm_bts_trx *trx)
 	unsigned int i;
 
 	LOGP(DRSL, LOGL_NOTICE, "bootstrapping RSL for BTS/TRX (%u/%u) "
-		"on ARFCN %u using MCC=%u MNC=%u LAC=%u CID=%u BSIC=%u\n",
-		trx->bts->nr, trx->nr, trx->arfcn, bsc_gsmnet->country_code,
-		bsc_gsmnet->network_code, trx->bts->location_area_code,
+		"on ARFCN %u using MCC-MNC %s LAC=%u CID=%u BSIC=%u\n",
+		trx->bts->nr, trx->nr, trx->arfcn,
+		osmo_plmn_name(&bsc_gsmnet->plmn),
+		trx->bts->location_area_code,
 		trx->bts->cell_identity, trx->bts->bsic);
 
 	/*
diff --git a/src/libbsc/bsc_vty.c b/src/libbsc/bsc_vty.c
index 47bc51483..29a3c80a3 100644
--- a/src/libbsc/bsc_vty.c
+++ b/src/libbsc/bsc_vty.c
@@ -203,9 +203,8 @@ static void net_dump_vty(struct vty *vty, struct gsm_network *net)
 	struct pchan_load pl;
 	int i;
 
-	vty_out(vty, "BSC is on Country Code %u, Network Code %u "
-		"and has %u BTS%s", net->country_code, net->network_code,
-		net->num_bts, VTY_NEWLINE);
+	vty_out(vty, "BSC is on MCC-MNC %s and has %u BTS%s",
+		osmo_plmn_name(&net->plmn), net->num_bts, VTY_NEWLINE);
 	vty_out(vty, "%s", VTY_NEWLINE);
 	vty_out(vty, "  Encryption:");
 	for (i = 0; i < 8; i++) {
@@ -955,8 +954,9 @@ static int config_write_net(struct vty *vty)
 	int i;
 
 	vty_out(vty, "network%s", VTY_NEWLINE);
-	vty_out(vty, " network country code %u%s", gsmnet->country_code, VTY_NEWLINE);
-	vty_out(vty, " mobile network code %u%s", gsmnet->network_code, VTY_NEWLINE);
+	vty_out(vty, " network country code %s%s", osmo_mcc_name(gsmnet->plmn.mcc), VTY_NEWLINE);
+	vty_out(vty, " mobile network code %s%s",
+		osmo_mnc_name(gsmnet->plmn.mnc, gsmnet->plmn.mnc_3_digits), VTY_NEWLINE);
 	vty_out(vty, " encryption a5");
 	for (i = 0; i < 8; i++) {
 		if (gsmnet->a5_encryption_mask & (1 << i))
@@ -4516,8 +4516,14 @@ DEFUN(cfg_net_ncc,
       "Network Country Code to use\n")
 {
 	struct gsm_network *gsmnet = gsmnet_from_vty(vty);
+	uint16_t mcc;
 
-	gsmnet->country_code = atoi(argv[0]);
+	if (osmo_mcc_from_str(argv[0], &mcc)) {
+		vty_out(vty, "%% Error decoding MCC: %s%s", argv[0], VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	gsmnet->plmn.mcc = mcc;
 
 	return CMD_SUCCESS;
 }
@@ -4531,8 +4537,16 @@ DEFUN(cfg_net_mnc,
       "Mobile Network Code to use\n")
 {
 	struct gsm_network *gsmnet = gsmnet_from_vty(vty);
+	uint16_t mnc;
+	bool mnc_3_digits;
+
+	if (osmo_mnc_from_str(argv[0], &mnc, &mnc_3_digits)) {
+		vty_out(vty, "%% Error decoding MNC: %s%s", argv[0], VTY_NEWLINE);
+		return CMD_WARNING;
+	}
 
-	gsmnet->network_code = atoi(argv[0]);
+	gsmnet->plmn.mnc = mnc;
+	gsmnet->plmn.mnc_3_digits = mnc_3_digits;
 
 	return CMD_SUCCESS;
 }
diff --git a/src/libbsc/gsm_data.c b/src/libbsc/gsm_data.c
index d4a6a70f9..686e9c54e 100644
--- a/src/libbsc/gsm_data.c
+++ b/src/libbsc/gsm_data.c
@@ -272,8 +272,9 @@ struct gsm_bts *gsm_bts_alloc_register(struct gsm_network *net, enum gsm_bts_typ
 void gprs_ra_id_by_bts(struct gprs_ra_id *raid, struct gsm_bts *bts)
 {
 	*raid = (struct gprs_ra_id){
-		.mcc = bts->network->country_code,
-		.mnc = bts->network->network_code,
+		.mcc = bts->network->plmn.mcc,
+		.mnc = bts->network->plmn.mnc,
+		.mnc_3_digits = bts->network->plmn.mnc_3_digits,
 		.lac = bts->location_area_code,
 		.rac = bts->gprs.rac,
 	};
diff --git a/src/libbsc/net_init.c b/src/libbsc/net_init.c
index e44c335d1..d5ea5b275 100644
--- a/src/libbsc/net_init.c
+++ b/src/libbsc/net_init.c
@@ -47,8 +47,10 @@ struct gsm_network *bsc_network_init(void *ctx)
 	if (!net)
 		return NULL;
 
-	net->country_code = 1;
-	net->network_code = 1;
+	net->plmn = (struct osmo_plmn_id){
+		.mcc = 1,
+		.mnc = 1,
+	};
 
 	/* Permit a compile-time default of A5/3 and A5/1 */
 	net->a5_encryption_mask = (1 << 3) | (1 << 1);
diff --git a/src/libbsc/pcu_sock.c b/src/libbsc/pcu_sock.c
index 9f1c80cc2..85af59842 100644
--- a/src/libbsc/pcu_sock.c
+++ b/src/libbsc/pcu_sock.c
@@ -152,8 +152,9 @@ static int pcu_tx_info_ind(struct gsm_bts *bts)
 		info_ind->flags |= PCU_IF_FLAG_SYSMO;
 
 	/* RAI */
-	info_ind->mcc = bts->network->country_code;
-	info_ind->mnc = bts->network->network_code;
+	info_ind->mcc = bts->network->plmn.mcc;
+	info_ind->mnc = bts->network->plmn.mnc;
+	/* TODO: plmn.mnc_3_digits */
 	info_ind->lac = bts->location_area_code;
 	info_ind->rac = bts->gprs.rac;
 
diff --git a/src/libbsc/system_information.c b/src/libbsc/system_information.c
index 750bba427..c7c85b043 100644
--- a/src/libbsc/system_information.c
+++ b/src/libbsc/system_information.c
@@ -860,9 +860,7 @@ static int generate_si3(enum osmo_sysinfo_type t, struct gsm_bts *bts)
 	si3->header.system_information = GSM48_MT_RR_SYSINFO_3;
 
 	si3->cell_identity = htons(bts->cell_identity);
-	gsm48_generate_lai(&si3->lai, bts->network->country_code,
-			   bts->network->network_code,
-			   bts->location_area_code);
+	gsm48_generate_lai2(&si3->lai, bts_lai(bts));
 	si3->control_channel_desc = bts->si_common.chan_desc;
 	si3->cell_options = bts->si_common.cell_options;
 	si3->cell_sel_par = bts->si_common.cell_sel_par;
@@ -914,9 +912,7 @@ static int generate_si4(enum osmo_sysinfo_type t, struct gsm_bts *bts)
 	si4->header.skip_indicator = 0;
 	si4->header.system_information = GSM48_MT_RR_SYSINFO_4;
 
-	gsm48_generate_lai(&si4->lai, bts->network->country_code,
-			   bts->network->network_code,
-			   bts->location_area_code);
+	gsm48_generate_lai2(&si4->lai, bts_lai(bts));
 	si4->cell_sel_par = bts->si_common.cell_sel_par;
 	si4->rach_control = bts->si_common.rach_control;
 	if (acc_ramp_is_enabled(&bts->acc_ramp))
@@ -1088,9 +1084,7 @@ static int generate_si6(enum osmo_sysinfo_type t, struct gsm_bts *bts)
 	si6->skip_indicator = 0;
 	si6->system_information = GSM48_MT_RR_SYSINFO_6;
 	si6->cell_identity = htons(bts->cell_identity);
-	gsm48_generate_lai(&si6->lai, bts->network->country_code,
-			   bts->network->network_code,
-			   bts->location_area_code);
+	gsm48_generate_lai2(&si6->lai, bts_lai(bts));
 	si6->cell_options = bts->si_common.cell_options;
 	si6->ncc_permitted = bts->si_common.ncc_permitted;
 	/* allow/disallow DTXu */
diff --git a/src/osmo-bsc/osmo_bsc_api.c b/src/osmo-bsc/osmo_bsc_api.c
index 465832c82..75dae1293 100644
--- a/src/osmo-bsc/osmo_bsc_api.c
+++ b/src/osmo-bsc/osmo_bsc_api.c
@@ -54,32 +54,20 @@ static int bsc_clear_request(struct gsm_subscriber_connection *conn, uint32_t ca
 static int complete_layer3(struct gsm_subscriber_connection *conn,
 			   struct msgb *msg, struct bsc_msc_data *msc);
 
-static uint16_t get_network_code_for_msc(struct bsc_msc_data *msc)
+static struct osmo_cell_global_id *cgi_for_msc(struct bsc_msc_data *msc, struct gsm_bts *bts)
 {
-	if (msc->core_mnc != -1)
-		return msc->core_mnc;
-	return msc->network->network_code;
-}
-
-static uint16_t get_country_code_for_msc(struct bsc_msc_data *msc)
-{
-	if (msc->core_mcc != -1)
-		return msc->core_mcc;
-	return msc->network->country_code;
-}
-
-static uint16_t get_lac_for_msc(struct bsc_msc_data *msc, struct gsm_bts *bts)
-{
-	if (msc->core_lac != -1)
-		return msc->core_lac;
-	return bts->location_area_code;
-}
+	static struct osmo_cell_global_id cgi;
+	cgi.lai.plmn = msc->network->plmn;
+	if (msc->core_plmn.mcc != GSM_MCC_MNC_INVALID)
+		cgi.lai.plmn.mcc = msc->core_plmn.mcc;
+	if (msc->core_plmn.mnc != GSM_MCC_MNC_INVALID) {
+		cgi.lai.plmn.mnc = msc->core_plmn.mnc;
+		cgi.lai.plmn.mnc_3_digits = msc->core_plmn.mnc_3_digits;
+	}
+	cgi.lai.lac = (msc->core_lac != -1) ? msc->core_lac : bts->location_area_code;
+	cgi.cell_identity = (msc->core_ci != -1) ? msc->core_ci : bts->cell_identity;
 
-static uint16_t get_ci_for_msc(struct bsc_msc_data *msc, struct gsm_bts *bts)
-{
-	if (msc->core_ci != -1)
-		return msc->core_ci;
-	return bts->cell_identity;
+	return &cgi;
 }
 
 static void bsc_maybe_lu_reject(struct gsm_subscriber_connection *conn, int con_type, int cause)
@@ -242,10 +230,6 @@ static int complete_layer3(struct gsm_subscriber_connection *conn,
 	char *imsi = NULL;
 	struct timeval tv;
 	struct msgb *resp;
-	uint16_t network_code;
-	uint16_t country_code;
-	uint16_t lac;
-	uint16_t ci;
 	enum bsc_con ret;
 	int send_ping = msc->advanced_ping;
 
@@ -285,14 +269,9 @@ static int complete_layer3(struct gsm_subscriber_connection *conn,
 
 	/* check return value, if failed check msg for and send USSD */
 
-	network_code = get_network_code_for_msc(conn->sccp.msc);
-	country_code = get_country_code_for_msc(conn->sccp.msc);
-	lac = get_lac_for_msc(conn->sccp.msc, conn_get_bts(conn));
-	ci = get_ci_for_msc(conn->sccp.msc, conn_get_bts(conn));
-
 	bsc_scan_bts_msg(conn, msg);
 
-	resp = gsm0808_create_layer3(msg, network_code, country_code, lac, ci);
+	resp = gsm0808_create_layer3_2(msg, cgi_for_msc(conn->sccp.msc, conn_get_bts(conn)), NULL);
 	if (!resp) {
 		LOGP(DMSC, LOGL_DEBUG, "Failed to create layer3 message.\n");
 		osmo_bsc_sigtran_del_conn(conn);
diff --git a/src/osmo-bsc/osmo_bsc_bssap.c b/src/osmo-bsc/osmo_bsc_bssap.c
index d07cc558e..db749a3da 100644
--- a/src/osmo-bsc/osmo_bsc_bssap.c
+++ b/src/osmo-bsc/osmo_bsc_bssap.c
@@ -262,15 +262,14 @@ page_subscriber(struct bsc_msc_data *msc, struct gsm_bts *bts,
 
 /* Decode 5-byte LAI list element data (see TS 08.08 3.2.2.27) into MCC/MNC/LAC.
  * Return 0 if successful, negative on error. */
-static int
-decode_lai(const uint8_t *data, uint16_t *mcc, uint16_t *mnc, uint16_t *lac)
+static void
+decode_lai(const uint8_t *data, struct osmo_location_area_id *laid)
 {
 	struct gsm48_loc_area_id lai;
 
 	/* Copy data to stack to prevent unaligned access in gsm48_decode_lai(). */
 	memcpy(&lai, data, sizeof(lai)); /* don't byte swap yet */
-
-	return gsm48_decode_lai(&lai, mcc, mnc, lac) != 0 ? -1 : 0;
+	gsm48_decode_lai2(&lai, laid);
 }
 
 static void
@@ -290,37 +289,33 @@ page_cgi(struct bsc_msc_data *msc, const uint8_t *data, uint8_t data_length, siz
 	uint16_t ci;
 	int i = 0;
 	while (remain >= sizeof(struct gsm48_loc_area_id) + sizeof(ci)) {
-		uint16_t mcc, mnc, lac, *ci_be;
+		struct osmo_location_area_id lai;
+		uint16_t *ci_be;
 		size_t lai_offset = 1 + i * (sizeof(struct gsm48_loc_area_id) + sizeof(ci));
-		if (decode_lai(&data[lai_offset], &mcc, &mnc, &lac) != 0) {
-			LOGP(DMSC, LOGL_ERROR, "Paging IMSI %s: Invalid LAI in Cell Identifier List "
-			     "for BSS (0x%x), paging entire BSS anyway (%s)\n",
-			     mi_string, CELL_IDENT_BSS, osmo_hexdump(data, data_length));
-			page_all_bts(msc, tmsi, mi_string, chan_needed);
-			return;
-		}
+		decode_lai(&data[lai_offset], &lai);
 		ci_be = (uint16_t *)(&data[lai_offset + sizeof(struct gsm48_loc_area_id)]);
 		ci = osmo_load16be(ci_be);
-		if (mcc == msc->network->country_code && mnc == msc->network->network_code) {
+		if (!osmo_plmn_cmp(&lai.plmn, &msc->network->plmn)) {
 			int paged = 0;
 			struct gsm_bts *bts;
 			llist_for_each_entry(bts, &msc->network->bts_list, list) {
-				if (bts->location_area_code != lac)
+				if (bts->location_area_code != lai.lac)
 					continue;
 				if (bts->cell_identity != ci)
 					continue;
 				/* ignore errors from page_subscriber(); keep trying other BTS */
-				page_subscriber(msc, bts, tmsi, lac, mi_string, chan_needed);
+				page_subscriber(msc, bts, tmsi, lai.lac, mi_string, chan_needed);
 				paged = 1;
 			}
 			if (!paged) {
 				LOGP(DMSC, LOGL_NOTICE, "Paging IMSI %s: BTS with LAC %d and CI %d not found\n",
-				     mi_string, lac, ci);
+				     mi_string, lai.lac, ci);
 			}
 		} else {
-			LOGP(DMSC, LOGL_DEBUG, "Paging IMSI %s: MCC/MNC in Cell Identifier List "
-			     "(%d/%d) do not match our network (%d/%d)\n", mi_string, mcc, mnc,
-			     msc->network->country_code, msc->network->network_code);
+			LOGP(DMSC, LOGL_DEBUG, "Paging IMSI %s: MCC-MNC in Cell Identifier List "
+			     "(%s) do not match our network (%s)\n",
+			     mi_string, osmo_plmn_name(&lai.plmn),
+			     osmo_plmn_name2(&msc->network->plmn));
 		}
 		remain -= sizeof(struct gsm48_loc_area_id) + sizeof(ci);
 		i++;
@@ -389,32 +384,27 @@ page_lai_and_lac(struct bsc_msc_data *msc, const uint8_t *data, size_t data_leng
 {
 	int i = 0;
 	while (remain >= sizeof(struct gsm48_loc_area_id)) {
-		uint16_t mcc, mnc, lac;
-		if (decode_lai(&data[1 + i * sizeof(struct gsm48_loc_area_id)], &mcc, &mnc, &lac) != 0) {
-			LOGP(DMSC, LOGL_ERROR, "Paging IMSI %s: Invalid LAI in Cell Identifier List "
-			     "for BSS (0x%x), paging entire BSS anyway (%s)\n",
-			     mi_string, CELL_IDENT_BSS, osmo_hexdump(data, data_length));
-			page_all_bts(msc, tmsi, mi_string, chan_needed);
-			return;
-		}
-		if (mcc == msc->network->country_code && mnc == msc->network->network_code) {
+		struct osmo_location_area_id lai;
+		decode_lai(&data[1 + i * sizeof(struct gsm48_loc_area_id)], &lai);
+		if (!osmo_plmn_cmp(&lai.plmn, &msc->network->plmn)) {
 			int paged = 0;
 			struct gsm_bts *bts;
 			llist_for_each_entry(bts, &msc->network->bts_list, list) {
-				if (bts->location_area_code != lac)
+				if (bts->location_area_code != lai.lac)
 					continue;
 				/* ignore errors from page_subscriber(); keep trying other BTS */
-				page_subscriber(msc, bts, tmsi, lac, mi_string, chan_needed);
+				page_subscriber(msc, bts, tmsi, lai.lac, mi_string, chan_needed);
 				paged = 1;
 			}
 			if (!paged) {
 				LOGP(DMSC, LOGL_NOTICE, "Paging IMSI %s: BTS with LAC %d not found\n",
-				     mi_string, lac);
+				     mi_string, lai.lac);
 			}
 		} else {
-			LOGP(DMSC, LOGL_DEBUG, "Paging IMSI %s: MCC/MNC in Cell Identifier List "
-			     "(%d/%d) do not match our network (%d/%d)\n", mi_string, mcc, mnc,
-			     msc->network->country_code, msc->network->network_code);
+			LOGP(DMSC, LOGL_DEBUG, "Paging IMSI %s: MCC-MNC in Cell Identifier List "
+			     "(%s) do not match our network (%s)\n",
+			     mi_string, osmo_plmn_name(&lai.plmn),
+			     osmo_plmn_name2(&msc->network->plmn));
 		}
 		remain -= sizeof(struct gsm48_loc_area_id);
 		i++;
diff --git a/src/osmo-bsc/osmo_bsc_ctrl.c b/src/osmo-bsc/osmo_bsc_ctrl.c
index 6092f2379..5f88b85f7 100644
--- a/src/osmo-bsc/osmo_bsc_ctrl.c
+++ b/src/osmo-bsc/osmo_bsc_ctrl.c
@@ -207,10 +207,11 @@ static void generate_location_state_trap(struct gsm_bts *bts, struct bsc_msc_con
 	policy = osmo_bsc_rf_get_policy_name(osmo_bsc_rf_get_policy_by_bts(bts));
 
 	cmd->reply = talloc_asprintf_append(cmd->reply,
-				",%s,%s,%s,%d,%d",
+				",%s,%s,%s,%s,%s",
 				oper, admin, policy,
-				bts->network->country_code,
-				bts->network->network_code);
+				osmo_mcc_name(bts->network->plmn.mcc),
+				osmo_mnc_name(bts->network->plmn.mnc,
+					      bts->network->plmn.mnc_3_digits));
 
 	osmo_bsc_send_trap(cmd, msc_con);
 	talloc_free(cmd);
diff --git a/src/osmo-bsc/osmo_bsc_filter.c b/src/osmo-bsc/osmo_bsc_filter.c
index c1f3e80a6..5f60989a7 100644
--- a/src/osmo-bsc/osmo_bsc_filter.c
+++ b/src/osmo-bsc/osmo_bsc_filter.c
@@ -36,21 +36,16 @@ static void handle_lu_request(struct gsm_subscriber_connection *conn,
 	struct gsm48_hdr *gh;
 	struct gsm48_loc_upd_req *lu;
 	struct gsm48_loc_area_id lai;
-	struct gsm_network *net;
-	struct gsm_bts *bts = conn_get_bts(conn);
 
 	if (msgb_l3len(msg) < sizeof(*gh) + sizeof(*lu)) {
 		LOGP(DMSC, LOGL_ERROR, "LU too small to look at: %u\n", msgb_l3len(msg));
 		return;
 	}
 
-	net = bts->network;
-
 	gh = msgb_l3(msg);
 	lu = (struct gsm48_loc_upd_req *) gh->data;
 
-	gsm48_generate_lai(&lai, net->country_code, net->network_code,
-			   bts->location_area_code);
+	gsm48_generate_lai2(&lai, bts_lai(conn_get_bts(conn)));
 
 	if (memcmp(&lai, &lu->lai, sizeof(lai)) != 0) {
 		LOGP(DMSC, LOGL_DEBUG, "Marking con for welcome USSD.\n");
@@ -315,9 +310,9 @@ static int bsc_patch_mm_info(struct gsm_subscriber_connection *conn,
 
 static int has_core_identity(struct bsc_msc_data *msc)
 {
-	if (msc->core_mnc != -1)
+	if (msc->core_plmn.mnc != GSM_MCC_MNC_INVALID)
 		return 1;
-	if (msc->core_mcc != -1)
+	if (msc->core_plmn.mcc != GSM_MCC_MNC_INVALID)
 		return 1;
 	if (msc->core_lac != -1)
 		return 1;
@@ -332,8 +327,6 @@ static int has_core_identity(struct bsc_msc_data *msc)
 int bsc_scan_msc_msg(struct gsm_subscriber_connection *conn, struct msgb *msg)
 {
 	struct bsc_msc_data *msc;
-	struct gsm_bts *bts = conn_get_bts(conn);
-	struct gsm_network *net;
 	struct gsm48_loc_area_id *lai;
 	struct gsm48_hdr *gh;
 	uint8_t pdisc;
@@ -353,7 +346,6 @@ int bsc_scan_msc_msg(struct gsm_subscriber_connection *conn, struct msgb *msg)
 		return 0;
 
 	mtype = gsm48_hdr_msg_type(gh);
-	net = bts->network;
 	msc = conn->sccp.msc;
 
 	if (mtype == GSM48_MT_MM_LOC_UPD_ACCEPT) {
@@ -361,9 +353,7 @@ int bsc_scan_msc_msg(struct gsm_subscriber_connection *conn, struct msgb *msg)
 			if (msgb_l3len(msg) >= sizeof(*gh) + sizeof(*lai)) {
 				/* overwrite LAI in the message */
 				lai = (struct gsm48_loc_area_id *) &gh->data[0];
-				gsm48_generate_lai(lai, net->country_code,
-						   net->network_code,
-						   bts->location_area_code);
+				gsm48_generate_lai2(lai, bts_lai(conn_get_bts(conn)));
 			}
 		}
 
diff --git a/src/osmo-bsc/osmo_bsc_msc.c b/src/osmo-bsc/osmo_bsc_msc.c
index 46be2e644..e0c7556a9 100644
--- a/src/osmo-bsc/osmo_bsc_msc.c
+++ b/src/osmo-bsc/osmo_bsc_msc.c
@@ -581,8 +581,10 @@ struct bsc_msc_data *osmo_msc_data_alloc(struct gsm_network *net, int nr)
 	INIT_LLIST_HEAD(&msc_data->dests);
 	msc_data->ping_timeout = 20;
 	msc_data->pong_timeout = 5;
-	msc_data->core_mnc = -1;
-	msc_data->core_mcc = -1;
+	msc_data->core_plmn = (struct osmo_plmn_id){
+		.mcc = GSM_MCC_MNC_INVALID,
+		.mnc = GSM_MCC_MNC_INVALID,
+	};
 	msc_data->core_ci = -1;
 	msc_data->core_lac = -1;
 	msc_data->rtp_base = 4000;
diff --git a/src/osmo-bsc/osmo_bsc_vty.c b/src/osmo-bsc/osmo_bsc_vty.c
index e173b4a7b..3455d01af 100644
--- a/src/osmo-bsc/osmo_bsc_vty.c
+++ b/src/osmo-bsc/osmo_bsc_vty.c
@@ -27,6 +27,7 @@
 #include <osmocom/bsc/bsc_msg_filter.h>
 
 #include <osmocom/core/talloc.h>
+#include <osmocom/gsm/gsm48.h>
 #include <osmocom/vty/logging.h>
 #include <osmocom/mgcp_client/mgcp_client.h>
 
@@ -107,12 +108,12 @@ static void write_msc(struct vty *vty, struct bsc_msc_data *msc)
 	struct bsc_msc_dest *dest;
 
 	vty_out(vty, "msc %d%s", msc->nr, VTY_NEWLINE);
-	if (msc->core_mnc != -1)
-		vty_out(vty, " core-mobile-network-code %d%s",
-			msc->core_mnc, VTY_NEWLINE);
-	if (msc->core_mcc != -1)
-		vty_out(vty, " core-mobile-country-code %d%s",
-			msc->core_mcc, VTY_NEWLINE);
+	if (msc->core_plmn.mnc != GSM_MCC_MNC_INVALID)
+		vty_out(vty, " core-mobile-network-code %s%s",
+			osmo_mnc_name(msc->core_plmn.mnc, msc->core_plmn.mnc_3_digits), VTY_NEWLINE);
+	if (msc->core_plmn.mcc != GSM_MCC_MNC_INVALID)
+		vty_out(vty, " core-mobile-country-code %s%s",
+			osmo_mcc_name(msc->core_plmn.mcc), VTY_NEWLINE);
 	if (msc->core_lac != -1)
 		vty_out(vty, " core-location-area-code %d%s",
 			msc->core_lac, VTY_NEWLINE);
@@ -236,7 +237,15 @@ DEFUN(cfg_net_bsc_ncc,
       "Use this network code for the core network\n" "MNC value\n")
 {
 	struct bsc_msc_data *data = bsc_msc_data(vty);
-	data->core_mnc = atoi(argv[0]);
+	uint16_t mnc;
+	bool mnc_3_digits;
+
+	if (osmo_mnc_from_str(argv[0], &mnc, &mnc_3_digits)) {
+		vty_out(vty, "%% Error decoding MNC: %s%s", argv[0], VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	data->core_plmn.mnc = mnc;
+	data->core_plmn.mnc_3_digits = mnc_3_digits;
 	return CMD_SUCCESS;
 }
 
@@ -245,8 +254,13 @@ DEFUN(cfg_net_bsc_mcc,
       "core-mobile-country-code <1-999>",
       "Use this country code for the core network\n" "MCC value\n")
 {
+	uint16_t mcc;
 	struct bsc_msc_data *data = bsc_msc_data(vty);
-	data->core_mcc = atoi(argv[0]);
+	if (osmo_mcc_from_str(argv[0], &mcc)) {
+		vty_out(vty, "%% Error decoding MCC: %s%s", argv[0], VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+	data->core_plmn.mcc = mcc;
 	return CMD_SUCCESS;
 }