Split gprs_sgsn.{c,h} -> {auth,mmctx,sgsn}.{c,h}
Some level of split already existed, like sgsn_auth.c, but headers were
entangled together.
Let's clearly separate application centric code (sgsn.c/h), auth related
code (auth.c/h) and mmctx related code (mmctx.c/h).
Change-Id: I048a082851c1275c959649942904205b02acce2a
diff --git a/src/sgsn/mmctx.c b/src/sgsn/mmctx.c
new file mode 100644
index 0000000..c40db21
--- /dev/null
+++ b/src/sgsn/mmctx.c
@@ -0,0 +1,586 @@
+/* Mobility Management context */
+
+/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <stdint.h>
+
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/timer.h>
+#include <osmocom/core/rate_ctr.h>
+#include <osmocom/core/stats.h>
+#include <osmocom/core/backtrace.h>
+#include <osmocom/ctrl/control_if.h>
+#include <osmocom/ctrl/ports.h>
+#include <osmocom/gprs/gprs_ns2.h>
+#include <osmocom/gprs/gprs_bssgp.h>
+#include <osmocom/gsm/protocol/gsm_04_08_gprs.h>
+#include <osmocom/gsm/apn.h>
+#include <osmocom/gsm/gsm_utils.h>
+#include <osmocom/gsm/gsup.h>
+
+#include <osmocom/sgsn/gprs_subscriber.h>
+#include <osmocom/sgsn/debug.h>
+#include <osmocom/sgsn/mmctx.h>
+#include <osmocom/sgsn/sgsn.h>
+#include <osmocom/sgsn/gprs_gmm.h>
+#include <osmocom/sgsn/gprs_sm.h>
+#include <osmocom/sgsn/gprs_utils.h>
+#include <osmocom/sgsn/signal.h>
+#include <osmocom/sgsn/gprs_gmm_attach.h>
+#include <osmocom/sgsn/gprs_mm_state_gb_fsm.h>
+#include <osmocom/sgsn/gprs_mm_state_iu_fsm.h>
+#include <osmocom/sgsn/gprs_gmm_fsm.h>
+#include <osmocom/sgsn/gprs_llc.h>
+#include <osmocom/sgsn/gprs_sndcp.h>
+#include <osmocom/sgsn/gtp_ggsn.h>
+#include <osmocom/sgsn/gtp.h>
+#include <osmocom/sgsn/pdpctx.h>
+
+#include <pdp.h>
+
+#include <time.h>
+
+#include "../../config.h"
+
+LLIST_HEAD(sgsn_mm_ctxts);
+
+const struct value_string sgsn_ran_type_names[] = {
+ { MM_CTX_T_GERAN_Gb, "GPRS/EDGE via Gb" },
+ { MM_CTX_T_UTRAN_Iu, "UMTS via Iu" },
+#if 0
+ { MM_CTX_T_GERAN_Iu, "GPRS/EDGE via Iu" },
+#endif
+ { 0, NULL }
+};
+
+static const struct rate_ctr_desc mmctx_ctr_description[] = {
+ { "sign:packets:in", "Signalling Messages ( In)" },
+ { "sign:packets:out", "Signalling Messages (Out)" },
+ { "udata:packets:in", "User Data Messages ( In)" },
+ { "udata:packets:out", "User Data Messages (Out)" },
+ { "udata:bytes:in", "User Data Bytes ( In)" },
+ { "udata:bytes:out", "User Data Bytes (Out)" },
+ { "pdp_ctx_act", "PDP Context Activations " },
+ { "suspend", "SUSPEND Count " },
+ { "paging:ps", "Paging Packet Switched " },
+ { "paging:cs", "Paging Circuit Switched " },
+ { "ra_update", "Routing Area Update " },
+};
+
+static const struct rate_ctr_group_desc mmctx_ctrg_desc = {
+ .group_name_prefix = "sgsn:mmctx",
+ .group_description = "SGSN MM Context Statistics",
+ .num_ctr = ARRAY_SIZE(mmctx_ctr_description),
+ .ctr_desc = mmctx_ctr_description,
+ .class_id = OSMO_STATS_CLASS_SUBSCRIBER,
+};
+
+/* look-up an SGSN MM context based on Iu UE context (struct ue_conn_ctx)*/
+struct sgsn_mm_ctx *sgsn_mm_ctx_by_ue_ctx(const void *uectx)
+{
+ struct sgsn_mm_ctx *ctx;
+
+ llist_for_each_entry(ctx, &sgsn_mm_ctxts, list) {
+ if (ctx->ran_type == MM_CTX_T_UTRAN_Iu
+ && uectx == ctx->iu.ue_ctx)
+ return ctx;
+ }
+
+ return NULL;
+}
+
+/* look-up a SGSN MM context based on TLLI + RAI */
+struct sgsn_mm_ctx *sgsn_mm_ctx_by_tlli(uint32_t tlli,
+ const struct gprs_ra_id *raid)
+{
+ struct sgsn_mm_ctx *ctx;
+
+ llist_for_each_entry(ctx, &sgsn_mm_ctxts, list) {
+ if ((tlli == ctx->gb.tlli || tlli == ctx->gb.tlli_new) &&
+ gprs_ra_id_equals(raid, &ctx->ra))
+ return ctx;
+ }
+
+ return NULL;
+}
+
+struct sgsn_mm_ctx *sgsn_mm_ctx_by_tlli_and_ptmsi(uint32_t tlli,
+ const struct gprs_ra_id *raid)
+{
+ struct sgsn_mm_ctx *ctx;
+ int tlli_type;
+
+ /* TODO: Also check the P_TMSI signature to be safe. That signature
+ * should be different (at least with a sufficiently high probability)
+ * after SGSN restarts and for multiple SGSN instances.
+ */
+
+ tlli_type = gprs_tlli_type(tlli);
+ if (tlli_type != TLLI_FOREIGN && tlli_type != TLLI_LOCAL)
+ return NULL;
+
+ llist_for_each_entry(ctx, &sgsn_mm_ctxts, list) {
+ if ((gprs_tmsi2tlli(ctx->p_tmsi, tlli_type) == tlli ||
+ gprs_tmsi2tlli(ctx->p_tmsi_old, tlli_type) == tlli) &&
+ gprs_ra_id_equals(raid, &ctx->ra))
+ return ctx;
+ }
+
+ return NULL;
+}
+
+struct sgsn_mm_ctx *sgsn_mm_ctx_by_ptmsi(uint32_t p_tmsi)
+{
+ struct sgsn_mm_ctx *ctx;
+
+ llist_for_each_entry(ctx, &sgsn_mm_ctxts, list) {
+ if (p_tmsi == ctx->p_tmsi ||
+ (ctx->p_tmsi_old && ctx->p_tmsi_old == p_tmsi))
+ return ctx;
+ }
+ return NULL;
+}
+
+struct sgsn_mm_ctx *sgsn_mm_ctx_by_imsi(const char *imsi)
+{
+ struct sgsn_mm_ctx *ctx;
+
+ llist_for_each_entry(ctx, &sgsn_mm_ctxts, list) {
+ if (!strcmp(imsi, ctx->imsi))
+ return ctx;
+ }
+ return NULL;
+
+}
+
+/* Allocate a new SGSN MM context, generic part */
+struct sgsn_mm_ctx *sgsn_mm_ctx_alloc(uint32_t rate_ctr_id)
+{
+ struct sgsn_mm_ctx *ctx;
+
+ ctx = talloc_zero(tall_sgsn_ctx, struct sgsn_mm_ctx);
+ if (!ctx)
+ return NULL;
+
+ ctx->auth_triplet.key_seq = GSM_KEY_SEQ_INVAL;
+ ctx->ctrg = rate_ctr_group_alloc(ctx, &mmctx_ctrg_desc, rate_ctr_id);
+ if (!ctx->ctrg) {
+ LOGMMCTXP(LOGL_ERROR, ctx, "Cannot allocate counter group\n");
+ talloc_free(ctx);
+ return NULL;
+ }
+
+ ctx->gmm_fsm = osmo_fsm_inst_alloc(&gmm_fsm, ctx, ctx, LOGL_DEBUG, "gmm_fsm");
+ if (!ctx->gmm_fsm)
+ goto out;
+ ctx->gmm_att_req.fsm = osmo_fsm_inst_alloc(&gmm_attach_req_fsm, ctx, ctx, LOGL_DEBUG, "gb_gmm_req");
+ if (!ctx->gmm_att_req.fsm)
+ goto out;
+ ctx->gb.mm_state_fsm = osmo_fsm_inst_alloc(&mm_state_gb_fsm, ctx, ctx, LOGL_DEBUG, NULL);
+ if (!ctx->gb.mm_state_fsm)
+ goto out;
+#ifdef BUILD_IU
+ ctx->iu.mm_state_fsm = osmo_fsm_inst_alloc(&mm_state_iu_fsm, ctx, ctx, LOGL_DEBUG, NULL);
+ if (!ctx->iu.mm_state_fsm)
+ goto out;
+#endif
+
+ INIT_LLIST_HEAD(&ctx->pdp_list);
+
+ llist_add(&ctx->list, &sgsn_mm_ctxts);
+
+ return ctx;
+
+out:
+ if (ctx->iu.mm_state_fsm)
+ osmo_fsm_inst_free(ctx->iu.mm_state_fsm);
+ if (ctx->gb.mm_state_fsm)
+ osmo_fsm_inst_free(ctx->gb.mm_state_fsm);
+ if (ctx->gmm_att_req.fsm)
+ osmo_fsm_inst_free(ctx->gmm_att_req.fsm);
+ if (ctx->gmm_fsm)
+ osmo_fsm_inst_free(ctx->gmm_fsm);
+
+ rate_ctr_group_free(ctx->ctrg);
+ talloc_free(ctx);
+
+ return NULL;
+}
+/* Allocate a new SGSN MM context for GERAN_Gb */
+struct sgsn_mm_ctx *sgsn_mm_ctx_alloc_gb(uint32_t tlli,
+ const struct gprs_ra_id *raid)
+{
+ struct sgsn_mm_ctx *ctx;
+
+ ctx = sgsn_mm_ctx_alloc(tlli);
+ if (!ctx)
+ return NULL;
+
+ memcpy(&ctx->ra, raid, sizeof(ctx->ra));
+ ctx->ran_type = MM_CTX_T_GERAN_Gb;
+ ctx->gb.tlli = tlli;
+ osmo_fsm_inst_update_id_f(ctx->gb.mm_state_fsm, "%" PRIu32, tlli);
+
+ return ctx;
+}
+
+/* Allocate a new SGSN MM context for UTRAN_Iu */
+struct sgsn_mm_ctx *sgsn_mm_ctx_alloc_iu(void *uectx)
+{
+#if BUILD_IU
+ struct sgsn_mm_ctx *ctx;
+ struct ranap_ue_conn_ctx *ue_ctx = uectx;
+
+ ctx = sgsn_mm_ctx_alloc(ue_ctx->conn_id);
+ if (!ctx)
+ return NULL;
+
+ /* Need to get RAID from IU conn */
+ ctx->ra = ue_ctx->ra_id;
+ ctx->ran_type = MM_CTX_T_UTRAN_Iu;
+ ctx->iu.ue_ctx = ue_ctx;
+ ctx->iu.ue_ctx->rab_assign_addr_enc = sgsn->cfg.iu.rab_assign_addr_enc;
+ ctx->iu.new_key = 1;
+ osmo_fsm_inst_update_id_f(ctx->iu.mm_state_fsm, "%" PRIu32, ue_ctx->conn_id);
+
+
+ return ctx;
+#else
+ return NULL;
+#endif
+}
+
+
+/* this is a hard _free_ function, it doesn't clean up the PDP contexts
+ * in libgtp! */
+static void sgsn_mm_ctx_free(struct sgsn_mm_ctx *mm)
+{
+ struct sgsn_pdp_ctx *pdp, *pdp2;
+
+ /* Unlink from global list of MM contexts */
+ llist_del(&mm->list);
+
+ /* Free all PDP contexts */
+ llist_for_each_entry_safe(pdp, pdp2, &mm->pdp_list, list)
+ sgsn_pdp_ctx_free(pdp);
+
+ rate_ctr_group_free(mm->ctrg);
+
+ talloc_free(mm);
+}
+
+void sgsn_mm_ctx_cleanup_free(struct sgsn_mm_ctx *mm)
+{
+ struct gprs_llc_llme *llme = NULL;
+ struct sgsn_pdp_ctx *pdp, *pdp2;
+ struct sgsn_signal_data sig_data;
+
+ if (mm->ran_type == MM_CTX_T_GERAN_Gb)
+ llme = mm->gb.llme;
+ else
+ OSMO_ASSERT(mm->gb.llme == NULL);
+
+ /* Forget about ongoing look-ups */
+ if (mm->ggsn_lookup) {
+ LOGMMCTXP(LOGL_NOTICE, mm,
+ "Cleaning mmctx with on-going query.\n");
+ mm->ggsn_lookup->mmctx = NULL;
+ mm->ggsn_lookup = NULL;
+ }
+
+ /* delete all existing PDP contexts for this MS */
+ llist_for_each_entry_safe(pdp, pdp2, &mm->pdp_list, list) {
+ LOGMMCTXP(LOGL_NOTICE, mm,
+ "Dropping PDP context for NSAPI=%u\n", pdp->nsapi);
+ sgsn_pdp_ctx_terminate(pdp);
+ }
+
+ if (osmo_timer_pending(&mm->timer)) {
+ LOGMMCTXP(LOGL_INFO, mm, "Cancelling MM timer %u\n", mm->T);
+ osmo_timer_del(&mm->timer);
+ }
+
+ memset(&sig_data, 0, sizeof(sig_data));
+ sig_data.mm = mm;
+ osmo_signal_dispatch(SS_SGSN, S_SGSN_MM_FREE, &sig_data);
+
+
+ /* Detach from subscriber which is possibly freed then */
+ if (mm->subscr) {
+ struct gprs_subscr *subscr = gprs_subscr_get(mm->subscr);
+ gprs_subscr_cleanup(subscr);
+ gprs_subscr_put(subscr);
+ }
+
+ if (mm->gmm_att_req.fsm)
+ gmm_att_req_free(mm);
+ if (mm->gb.mm_state_fsm)
+ osmo_fsm_inst_free(mm->gb.mm_state_fsm);
+ if (mm->iu.mm_state_fsm)
+ osmo_fsm_inst_free(mm->iu.mm_state_fsm);
+ if (mm->gmm_fsm)
+ osmo_fsm_inst_free(mm->gmm_fsm);
+
+ sgsn_mm_ctx_free(mm);
+ mm = NULL;
+
+ if (llme) {
+ /* TLLI unassignment, must be called after sgsn_mm_ctx_free */
+ if (gprs_llgmm_unassign(llme) < 0)
+ LOGMMCTXP(LOGL_ERROR, mm, "gprs_llgmm_unassign failed, llme not freed!\n");
+ }
+}
+
+
+/* look up PDP context by MM context and NSAPI */
+struct sgsn_pdp_ctx *sgsn_pdp_ctx_by_nsapi(const struct sgsn_mm_ctx *mm,
+ uint8_t nsapi)
+{
+ struct sgsn_pdp_ctx *pdp;
+
+ llist_for_each_entry(pdp, &mm->pdp_list, list) {
+ if (pdp->nsapi == nsapi)
+ return pdp;
+ }
+ return NULL;
+}
+
+/* look up PDP context by MM context and transaction ID */
+struct sgsn_pdp_ctx *sgsn_pdp_ctx_by_tid(const struct sgsn_mm_ctx *mm,
+ uint8_t tid)
+{
+ struct sgsn_pdp_ctx *pdp;
+
+ llist_for_each_entry(pdp, &mm->pdp_list, list) {
+ if (pdp->ti == tid)
+ return pdp;
+ }
+ return NULL;
+}
+
+uint32_t sgsn_alloc_ptmsi(void)
+{
+ struct sgsn_mm_ctx *mm;
+ uint32_t ptmsi = 0xdeadbeef;
+ int max_retries = 100, rc = 0;
+
+restart:
+ rc = osmo_get_rand_id((uint8_t *) &ptmsi, sizeof(ptmsi));
+ if (rc < 0)
+ goto failed;
+
+ /* Enforce that the 2 MSB are set without loosing the distance between
+ * identical values. Since rand() has no duplicate values within a
+ * period (because the size of the state is the same like the size of
+ * the random value), this leads to a distance of period/4 when the
+ * distribution of the 2 MSB is uniform. This approach fails with a
+ * probability of (3/4)^max_retries, only 1% of the approaches will
+ * need more than 16 numbers (even distribution assumed).
+ *
+ * Alternatively, a freeze list could be used if another PRNG is used
+ * or when this approach proves to be not sufficient.
+ */
+ if (ptmsi >= GSM23003_TMSI_SGSN_MASK) {
+ if (!max_retries--)
+ goto failed;
+ goto restart;
+ }
+ ptmsi |= GSM23003_TMSI_SGSN_MASK;
+
+ if (ptmsi == GSM_RESERVED_TMSI) {
+ if (!max_retries--)
+ goto failed;
+ goto restart;
+ }
+
+ llist_for_each_entry(mm, &sgsn_mm_ctxts, list) {
+ if (mm->p_tmsi == ptmsi) {
+ if (!max_retries--)
+ goto failed;
+ goto restart;
+ }
+ }
+
+ return ptmsi;
+
+failed:
+ LOGP(DGPRS, LOGL_ERROR, "Failed to allocate a P-TMSI: %d (%s)\n", rc, strerror(-rc));
+ return GSM_RESERVED_TMSI;
+}
+
+void sgsn_update_subscriber_data(struct sgsn_mm_ctx *mmctx)
+{
+ OSMO_ASSERT(mmctx != NULL);
+ LOGMMCTXP(LOGL_INFO, mmctx, "Subscriber data update\n");
+
+ sgsn_auth_update(mmctx);
+}
+
+static void insert_extra(struct tlv_parsed *tp,
+ struct sgsn_subscriber_data *data,
+ struct sgsn_subscriber_pdp_data *pdp)
+{
+ tp->lv[OSMO_IE_GSM_SUB_QOS].len = pdp->qos_subscribed_len;
+ tp->lv[OSMO_IE_GSM_SUB_QOS].val = pdp->qos_subscribed;
+
+ /* Prefer PDP charging characteristics of per subscriber one */
+ if (pdp->has_pdp_charg) {
+ tp->lv[OSMO_IE_GSM_CHARG_CHAR].len = sizeof(pdp->pdp_charg);
+ tp->lv[OSMO_IE_GSM_CHARG_CHAR].val = &pdp->pdp_charg[0];
+ } else if (data->has_pdp_charg) {
+ tp->lv[OSMO_IE_GSM_CHARG_CHAR].len = sizeof(data->pdp_charg);
+ tp->lv[OSMO_IE_GSM_CHARG_CHAR].val = &data->pdp_charg[0];
+ }
+}
+
+/**
+ * The tlv_parsed tp parameter will be modified to insert a
+ * OSMO_IE_GSM_SUB_QOS in case the data is available in the
+ * PDP context handling.
+ */
+struct sgsn_ggsn_ctx *sgsn_mm_ctx_find_ggsn_ctx(struct sgsn_mm_ctx *mmctx,
+ struct tlv_parsed *tp,
+ enum gsm48_gsm_cause *gsm_cause,
+ char *out_apn_str)
+{
+ char req_apn_str[GSM_APN_LENGTH] = {0};
+ const struct apn_ctx *apn_ctx = NULL;
+ const char *selected_apn_str = NULL;
+ struct sgsn_subscriber_pdp_data *pdp;
+ struct sgsn_ggsn_ctx *ggsn = NULL;
+ int allow_any_apn = 0;
+
+ out_apn_str[0] = '\0';
+
+ if (TLVP_PRESENT(tp, GSM48_IE_GSM_APN)) {
+ if (TLVP_LEN(tp, GSM48_IE_GSM_APN) >= GSM_APN_LENGTH - 1) {
+ LOGMMCTXP(LOGL_ERROR, mmctx, "APN IE too long\n");
+ *gsm_cause = GSM_CAUSE_INV_MAND_INFO;
+ return NULL;
+ }
+
+ osmo_apn_to_str(req_apn_str,
+ TLVP_VAL(tp, GSM48_IE_GSM_APN),
+ TLVP_LEN(tp, GSM48_IE_GSM_APN));
+
+ if (strcmp(req_apn_str, "*") == 0)
+ req_apn_str[0] = 0;
+ }
+
+ if (mmctx->subscr == NULL)
+ allow_any_apn = 1;
+
+ if (strlen(req_apn_str) == 0 && !allow_any_apn) {
+ /* No specific APN requested, check for an APN that is both
+ * granted and configured */
+
+ llist_for_each_entry(pdp, &mmctx->subscr->sgsn_data->pdp_list, list) {
+ if (strcmp(pdp->apn_str, "*") == 0)
+ {
+ allow_any_apn = 1;
+ selected_apn_str = "";
+ insert_extra(tp, mmctx->subscr->sgsn_data, pdp);
+ continue;
+ }
+ if (!llist_empty(&sgsn->apn_list)) {
+ apn_ctx = sgsn_apn_ctx_match(req_apn_str, mmctx->imsi);
+ /* Not configured */
+ if (apn_ctx == NULL)
+ continue;
+ }
+ insert_extra(tp, mmctx->subscr->sgsn_data, pdp);
+ selected_apn_str = pdp->apn_str;
+ break;
+ }
+ } else if (!allow_any_apn) {
+ /* Check whether the given APN is granted */
+ llist_for_each_entry(pdp, &mmctx->subscr->sgsn_data->pdp_list, list) {
+ if (strcmp(pdp->apn_str, "*") == 0) {
+ insert_extra(tp, mmctx->subscr->sgsn_data, pdp);
+ selected_apn_str = req_apn_str;
+ allow_any_apn = 1;
+ continue;
+ }
+ if (strcasecmp(pdp->apn_str, req_apn_str) == 0) {
+ insert_extra(tp, mmctx->subscr->sgsn_data, pdp);
+ selected_apn_str = req_apn_str;
+ break;
+ }
+ }
+ } else if (strlen(req_apn_str) != 0) {
+ /* Any APN is allowed */
+ selected_apn_str = req_apn_str;
+ } else {
+ /* Prefer the GGSN associated with the wildcard APN */
+ selected_apn_str = "";
+ }
+
+ if (!allow_any_apn && selected_apn_str == NULL) {
+ /* Access not granted */
+ LOGMMCTXP(LOGL_NOTICE, mmctx,
+ "The requested APN '%s' is not allowed\n",
+ req_apn_str);
+ *gsm_cause = GSM_CAUSE_REQ_SERV_OPT_NOTSUB;
+ return NULL;
+ }
+
+ /* copy the selected apn_str */
+ if (selected_apn_str)
+ strcpy(out_apn_str, selected_apn_str);
+ else
+ out_apn_str[0] = '\0';
+
+ if (apn_ctx == NULL && selected_apn_str)
+ apn_ctx = sgsn_apn_ctx_match(selected_apn_str, mmctx->imsi);
+
+ if (apn_ctx != NULL) {
+ ggsn = apn_ctx->ggsn;
+ } else if (llist_empty(&sgsn->apn_list)) {
+ /* No configuration -> use GGSN 0 */
+ ggsn = sgsn_ggsn_ctx_by_id(sgsn, 0);
+ } else if (allow_any_apn &&
+ (selected_apn_str == NULL || strlen(selected_apn_str) == 0)) {
+ /* No APN given and no default configuration -> Use GGSN 0 */
+ ggsn = sgsn_ggsn_ctx_by_id(sgsn, 0);
+ } else {
+ /* No matching configuration found */
+ LOGMMCTXP(LOGL_NOTICE, mmctx,
+ "The selected APN '%s' has not been configured\n",
+ selected_apn_str);
+ *gsm_cause = GSM_CAUSE_MISSING_APN;
+ return NULL;
+ }
+
+ if (!ggsn) {
+ LOGMMCTXP(LOGL_NOTICE, mmctx,
+ "No static GGSN configured. Selected APN '%s'\n",
+ selected_apn_str);
+ *gsm_cause = GSM_CAUSE_MISSING_APN;
+ return NULL;
+ }
+
+ LOGMMCTXP(LOGL_INFO, mmctx,
+ "Found GGSN %d for APN '%s' (requested '%s')\n",
+ ggsn->id, selected_apn_str ? selected_apn_str : "---",
+ req_apn_str);
+
+ return ggsn;
+}