diff options
Diffstat (limited to 'src/sgsn/gprs_sgsn.c')
| -rw-r--r-- | src/sgsn/gprs_sgsn.c | 1017 |
1 files changed, 1017 insertions, 0 deletions
diff --git a/src/sgsn/gprs_sgsn.c b/src/sgsn/gprs_sgsn.c new file mode 100644 index 000000000..387c0d5a1 --- /dev/null +++ b/src/sgsn/gprs_sgsn.c @@ -0,0 +1,1017 @@ +/* GPRS SGSN functionality */ + +/* (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/gprs/gprs_ns.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/gprs_sgsn.h> +#include <osmocom/sgsn/sgsn.h> +#include <osmocom/sgsn/gprs_gmm.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_llc.h> + +#include <pdp.h> + +#include <time.h> + +#include "../../bscconfig.h" + +#define GPRS_LLME_CHECK_TICK 30 + +extern struct sgsn_instance *sgsn; +extern void *tall_sgsn_ctx; + +LLIST_HEAD(sgsn_mm_ctxts); +LLIST_HEAD(sgsn_ggsn_ctxts); +LLIST_HEAD(sgsn_apn_ctxts); +LLIST_HEAD(sgsn_pdp_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, +}; + +static const struct rate_ctr_desc pdpctx_ctr_description[] = { + { "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)" }, +}; + +static const struct rate_ctr_group_desc pdpctx_ctrg_desc = { + .group_name_prefix = "sgsn:pdpctx", + .group_description = "SGSN PDP Context Statistics", + .num_ctr = ARRAY_SIZE(pdpctx_ctr_description), + .ctr_desc = pdpctx_ctr_description, + .class_id = OSMO_STATS_CLASS_SUBSCRIBER, +}; + +static const struct rate_ctr_desc sgsn_ctr_description[] = { + { "llc:dl_bytes", "Count sent LLC bytes before giving it to the bssgp layer" }, + { "llc:ul_bytes", "Count successful received LLC bytes (encrypt & fcs correct)" }, + { "llc:dl_packets", "Count successful sent LLC packets before giving it to the bssgp layer" }, + { "llc:ul_packets", "Count successful received LLC packets (encrypt & fcs correct)" }, + { "gprs:attach_requested", "Received attach requests" }, + { "gprs:attach_accepted", "Sent attach accepts" }, + { "gprs:attach_rejected", "Sent attach rejects" }, + { "gprs:detach_requested", "Received detach requests" }, + { "gprs:detach_acked", "Sent detach acks" }, + { "gprs:routing_area_requested", "Received routing area requests" }, + { "gprs:routing_area_requested", "Sent routing area acks" }, + { "gprs:routing_area_requested", "Sent routing area rejects" }, + { "pdp:activate_requested", "Received activate requests" }, + { "pdp:activate_rejected", "Sent activate rejects" }, + { "pdp:activate_accepted", "Sent activate accepts" }, + { "pdp:request_activated", "unused" }, + { "pdp:request_activate_rejected", "unused" }, + { "pdp:modify_requested", "unused" }, + { "pdp:modify_accepted", "unused" }, + { "pdp:dl_deactivate_requested", "Sent deactivate requests" }, + { "pdp:dl_deactivate_accepted", "Sent deactivate accepted" }, + { "pdp:ul_deactivate_requested", "Received deactivate requests" }, + { "pdp:ul_deactivate_accepted", "Received deactivate accepts" }, +}; + +static const struct rate_ctr_group_desc sgsn_ctrg_desc = { + "sgsn", + "SGSN Overall Statistics", + OSMO_STATS_CLASS_GLOBAL, + ARRAY_SIZE(sgsn_ctr_description), + sgsn_ctr_description, +}; + +void sgsn_rate_ctr_init() { + sgsn->rate_ctrs = rate_ctr_group_alloc(tall_sgsn_ctx, &sgsn_ctrg_desc, 0); + OSMO_ASSERT(sgsn->rate_ctrs); +} + +/* 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->gmm_state = GMM_DEREGISTERED; + 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_att_req.fsm = osmo_fsm_inst_alloc(&gmm_attach_req_fsm, ctx, ctx, LOGL_DEBUG, "gb_gmm_req"); + INIT_LLIST_HEAD(&ctx->pdp_list); + + llist_add(&ctx->list, &sgsn_mm_ctxts); + + return ctx; +} +/* 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; + char buf[32]; + + 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; + ctx->ciph_algo = sgsn->cfg.cipher; + snprintf(buf, sizeof(buf), "%" PRIu32, tlli); + ctx->gb.mm_state_fsm = osmo_fsm_inst_alloc(&mm_state_gb_fsm, ctx, ctx, LOGL_DEBUG, buf); + + LOGMMCTXP(LOGL_DEBUG, ctx, "Allocated with %s cipher.\n", + get_value_string(gprs_cipher_names, ctx->ciph_algo)); + 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 + char buf[32]; + 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; + snprintf(buf, sizeof(buf), "%" PRIu32, ue_ctx->conn_id); + ctx->iu.mm_state_fsm = osmo_fsm_inst_alloc(&mm_state_iu_fsm, ctx, ctx, LOGL_DEBUG, buf); + + + 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); + + 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; +} + +/* you don't want to use this directly, call sgsn_create_pdp_ctx() */ +struct sgsn_pdp_ctx *sgsn_pdp_ctx_alloc(struct sgsn_mm_ctx *mm, + struct sgsn_ggsn_ctx *ggsn, + uint8_t nsapi) +{ + struct sgsn_pdp_ctx *pdp; + + pdp = sgsn_pdp_ctx_by_nsapi(mm, nsapi); + if (pdp) + return NULL; + + pdp = talloc_zero(tall_sgsn_ctx, struct sgsn_pdp_ctx); + if (!pdp) + return NULL; + + pdp->mm = mm; + pdp->ggsn = ggsn; + pdp->nsapi = nsapi; + pdp->ctrg = rate_ctr_group_alloc(pdp, &pdpctx_ctrg_desc, nsapi); + if (!pdp->ctrg) { + LOGPDPCTXP(LOGL_ERROR, pdp, "Error allocation counter group\n"); + talloc_free(pdp); + return NULL; + } + llist_add(&pdp->list, &mm->pdp_list); + sgsn_ggsn_ctx_add_pdp(pdp->ggsn, pdp); + llist_add(&pdp->g_list, &sgsn_pdp_ctxts); + + return pdp; +} + +/* + * This function will not trigger any GSM DEACT PDP ACK messages, so you + * probably want to call sgsn_delete_pdp_ctx() instead if the connection + * isn't detached already. + */ +void sgsn_pdp_ctx_terminate(struct sgsn_pdp_ctx *pdp) +{ + struct sgsn_signal_data sig_data; + + OSMO_ASSERT(pdp->mm != NULL); + + /* There might still be pending callbacks in libgtp. So the parts of + * this object relevant to GTP need to remain intact in this case. */ + + LOGPDPCTXP(LOGL_INFO, pdp, "Forcing release of PDP context\n"); + + if (pdp->mm->ran_type == MM_CTX_T_GERAN_Gb) { + /* Force the deactivation of the SNDCP layer */ + sndcp_sm_deactivate_ind(&pdp->mm->gb.llme->lle[pdp->sapi], pdp->nsapi); + } + + memset(&sig_data, 0, sizeof(sig_data)); + sig_data.pdp = pdp; + osmo_signal_dispatch(SS_SGSN, S_SGSN_PDP_TERMINATE, &sig_data); + + /* Detach from MM context */ + pdp_ctx_detach_mm_ctx(pdp); + if (pdp->ggsn) + sgsn_delete_pdp_ctx(pdp); +} + +/* + * Don't call this function directly unless you know what you are doing. + * In normal conditions use sgsn_delete_pdp_ctx and in unspecified or + * implementation dependent abnormal ones sgsn_pdp_ctx_terminate. + */ +void sgsn_pdp_ctx_free(struct sgsn_pdp_ctx *pdp) +{ + struct sgsn_signal_data sig_data; + + memset(&sig_data, 0, sizeof(sig_data)); + sig_data.pdp = pdp; + osmo_signal_dispatch(SS_SGSN, S_SGSN_PDP_FREE, &sig_data); + + rate_ctr_group_free(pdp->ctrg); + if (pdp->mm) + llist_del(&pdp->list); + if (pdp->ggsn) + sgsn_ggsn_ctx_remove_pdp(pdp->ggsn, pdp); + llist_del(&pdp->g_list); + + /* _if_ we still have a library handle, at least set it to NULL + * to avoid any dereferences of the now-deleted PDP context from + * sgsn_libgtp:cb_data_ind() */ + if (pdp->lib) { + struct pdp_t *lib = pdp->lib; + LOGPDPCTXP(LOGL_NOTICE, pdp, "freeing PDP context that still " + "has a libgtp handle attached to it, this shouldn't " + "happen!\n"); + osmo_generate_backtrace(); + lib->priv = NULL; + } + + talloc_free(pdp); +} + +void sgsn_ggsn_ctx_check_echo_timer(struct sgsn_ggsn_ctx *ggc) +{ + bool pending = osmo_timer_pending(&ggc->echo_timer); + + /* Only enable if allowed by policy and at least 1 pdp ctx exists against ggsn */ + if (!llist_empty(&ggc->pdp_list) && ggc->echo_interval) { + if (!pending) + osmo_timer_schedule(&ggc->echo_timer, ggc->echo_interval, 0); + } else { + if (pending) + osmo_timer_del(&ggc->echo_timer); + } +} + +/* GGSN contexts */ +static void echo_timer_cb(void *data) +{ + struct sgsn_ggsn_ctx *ggc = (struct sgsn_ggsn_ctx *) data; + sgsn_ggsn_echo_req(ggc); + osmo_timer_schedule(&ggc->echo_timer, ggc->echo_interval, 0); +} + +struct sgsn_ggsn_ctx *sgsn_ggsn_ctx_alloc(uint32_t id) +{ + struct sgsn_ggsn_ctx *ggc; + + ggc = talloc_zero(tall_sgsn_ctx, struct sgsn_ggsn_ctx); + if (!ggc) + return NULL; + + ggc->id = id; + ggc->gtp_version = 1; + ggc->remote_restart_ctr = -1; + /* if we are called from config file parse, this gsn doesn't exist yet */ + ggc->gsn = sgsn->gsn; + INIT_LLIST_HEAD(&ggc->pdp_list); + osmo_timer_setup(&ggc->echo_timer, echo_timer_cb, ggc); + llist_add(&ggc->list, &sgsn_ggsn_ctxts); + + return ggc; +} + +void sgsn_ggsn_ctx_free(struct sgsn_ggsn_ctx *ggc) +{ + OSMO_ASSERT(llist_empty(&ggc->pdp_list)); + llist_del(&ggc->list); + talloc_free(ggc); +} + +struct sgsn_ggsn_ctx *sgsn_ggsn_ctx_by_id(uint32_t id) +{ + struct sgsn_ggsn_ctx *ggc; + + llist_for_each_entry(ggc, &sgsn_ggsn_ctxts, list) { + if (id == ggc->id) + return ggc; + } + return NULL; +} + +struct sgsn_ggsn_ctx *sgsn_ggsn_ctx_by_addr(struct in_addr *addr) +{ + struct sgsn_ggsn_ctx *ggc; + + llist_for_each_entry(ggc, &sgsn_ggsn_ctxts, list) { + if (!memcmp(addr, &ggc->remote_addr, sizeof(*addr))) + return ggc; + } + return NULL; +} + + +struct sgsn_ggsn_ctx *sgsn_ggsn_ctx_find_alloc(uint32_t id) +{ + struct sgsn_ggsn_ctx *ggc; + + ggc = sgsn_ggsn_ctx_by_id(id); + if (!ggc) + ggc = sgsn_ggsn_ctx_alloc(id); + return ggc; +} + +/* APN contexts */ + +static struct apn_ctx *sgsn_apn_ctx_alloc(const char *ap_name, const char *imsi_prefix) +{ + struct apn_ctx *actx; + + actx = talloc_zero(tall_sgsn_ctx, struct apn_ctx); + if (!actx) + return NULL; + actx->name = talloc_strdup(actx, ap_name); + actx->imsi_prefix = talloc_strdup(actx, imsi_prefix); + + llist_add_tail(&actx->list, &sgsn_apn_ctxts); + + return actx; +} + +void sgsn_apn_ctx_free(struct apn_ctx *actx) +{ + llist_del(&actx->list); + talloc_free(actx); +} + +struct apn_ctx *sgsn_apn_ctx_match(const char *name, const char *imsi) +{ + struct apn_ctx *actx; + struct apn_ctx *found_actx = NULL; + size_t imsi_prio = 0; + size_t name_prio = 0; + size_t name_req_len = strlen(name); + + llist_for_each_entry(actx, &sgsn_apn_ctxts, list) { + size_t name_ref_len, imsi_ref_len; + const char *name_ref_start, *name_match_start; + + imsi_ref_len = strlen(actx->imsi_prefix); + if (strncmp(actx->imsi_prefix, imsi, imsi_ref_len) != 0) + continue; + + if (imsi_ref_len < imsi_prio) + continue; + + /* IMSI matches */ + + name_ref_start = &actx->name[0]; + if (name_ref_start[0] == '*') { + /* Suffix match */ + name_ref_start += 1; + name_ref_len = strlen(name_ref_start); + if (name_ref_len > name_req_len) + continue; + } else { + name_ref_len = strlen(name_ref_start); + if (name_ref_len != name_req_len) + continue; + } + + name_match_start = name + (name_req_len - name_ref_len); + if (strcasecmp(name_match_start, name_ref_start) != 0) + continue; + + /* IMSI and name match */ + + if (imsi_ref_len == imsi_prio && name_ref_len < name_prio) + /* Lower priority, skip */ + continue; + + imsi_prio = imsi_ref_len; + name_prio = name_ref_len; + found_actx = actx; + } + return found_actx; +} + +struct apn_ctx *sgsn_apn_ctx_by_name(const char *name, const char *imsi_prefix) +{ + struct apn_ctx *actx; + + llist_for_each_entry(actx, &sgsn_apn_ctxts, list) { + if (strcasecmp(name, actx->name) == 0 && + strcasecmp(imsi_prefix, actx->imsi_prefix) == 0) + return actx; + } + return NULL; +} + +struct apn_ctx *sgsn_apn_ctx_find_alloc(const char *name, const char *imsi_prefix) +{ + struct apn_ctx *actx; + + actx = sgsn_apn_ctx_by_name(name, imsi_prefix); + if (!actx) + actx = sgsn_apn_ctx_alloc(name, imsi_prefix); + + return actx; +} + +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_ggsn_ctx_drop_pdp(struct sgsn_pdp_ctx *pctx) +{ + /* the MM context can be deleted while the GGSN is not reachable or + * if has been crashed. */ + if (pctx->mm && pctx->mm->gmm_state == GMM_REGISTERED_NORMAL) { + gsm48_tx_gsm_deact_pdp_req(pctx, GSM_CAUSE_NET_FAIL, true); + sgsn_ggsn_ctx_remove_pdp(pctx->ggsn, pctx); + } else { + /* FIXME: GPRS paging in case MS is SUSPENDED */ + LOGPDPCTXP(LOGL_NOTICE, pctx, "Hard-dropping PDP ctx due to GGSN " + "recovery\n"); + /* FIXME: how to tell this to libgtp? */ + sgsn_pdp_ctx_free(pctx); + } +} + +/* High-level function to be called in case a GGSN has disappeared or + * otherwise lost state (recovery procedure). It will detach all related pdp ctx + * from a ggsn and communicate deact to MS. Optionally (!NULL), one pdp ctx can + * be kept alive to allow handling later message which contained the Recovery IE. */ +int sgsn_ggsn_ctx_drop_all_pdp_except(struct sgsn_ggsn_ctx *ggsn, struct sgsn_pdp_ctx *except) +{ + int num = 0; + + struct sgsn_pdp_ctx *pdp, *pdp2; + llist_for_each_entry_safe(pdp, pdp2, &ggsn->pdp_list, ggsn_list) { + if (pdp == except) + continue; + sgsn_ggsn_ctx_drop_pdp(pdp); + num++; + } + + return num; +} + +int sgsn_ggsn_ctx_drop_all_pdp(struct sgsn_ggsn_ctx *ggsn) +{ + return sgsn_ggsn_ctx_drop_all_pdp_except(ggsn, NULL); +} + +void sgsn_ggsn_ctx_add_pdp(struct sgsn_ggsn_ctx *ggc, struct sgsn_pdp_ctx *pdp) +{ + llist_add(&pdp->ggsn_list, &ggc->pdp_list); + sgsn_ggsn_ctx_check_echo_timer(ggc); +} +void sgsn_ggsn_ctx_remove_pdp(struct sgsn_ggsn_ctx *ggc, struct sgsn_pdp_ctx *pdp) +{ + llist_del(&pdp->ggsn_list); + sgsn_ggsn_ctx_check_echo_timer(ggc); + if (pdp->destroy_ggsn) + sgsn_ggsn_ctx_free(pdp->ggsn); + pdp->ggsn = NULL; + /* Drop references to libgtp since the conn is down */ + if (pdp->lib) + pdp_freepdp(pdp->lib); + pdp->lib = NULL; +} + +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_ctxts)) { + 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_ctxts)) { + /* No configuration -> use GGSN 0 */ + ggsn = sgsn_ggsn_ctx_by_id(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(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; +} + +static void sgsn_llme_cleanup_free(struct gprs_llc_llme *llme) +{ + struct sgsn_mm_ctx *mmctx = NULL; + + llist_for_each_entry(mmctx, &sgsn_mm_ctxts, list) { + if (llme == mmctx->gb.llme) { + gsm0408_gprs_access_cancelled(mmctx, SGSN_ERROR_CAUSE_NONE); + return; + } + } + + /* No MM context found */ + LOGP(DGPRS, LOGL_INFO, "Deleting orphaned LLME, TLLI 0x%08x\n", + llme->tlli); + gprs_llgmm_unassign(llme); +} + +static void sgsn_llme_check_cb(void *data_) +{ + struct gprs_llc_llme *llme, *llme_tmp; + struct timespec now_tp; + time_t now, age; + time_t max_age = gprs_max_time_to_idle(); + + int rc; + + rc = osmo_clock_gettime(CLOCK_MONOTONIC, &now_tp); + OSMO_ASSERT(rc >= 0); + now = now_tp.tv_sec; + + LOGP(DGPRS, LOGL_DEBUG, + "Checking for inactive LLMEs, time = %u\n", (unsigned)now); + + llist_for_each_entry_safe(llme, llme_tmp, &gprs_llc_llmes, list) { + if (llme->age_timestamp == GPRS_LLME_RESET_AGE) + llme->age_timestamp = now; + + age = now - llme->age_timestamp; + + if (age > max_age || age < 0) { + LOGP(DGPRS, LOGL_INFO, + "Inactivity timeout for TLLI 0x%08x, age %d\n", + llme->tlli, (int)age); + sgsn_llme_cleanup_free(llme); + } + } + + osmo_timer_schedule(&sgsn->llme_timer, GPRS_LLME_CHECK_TICK, 0); +} + +struct sgsn_instance *sgsn_instance_alloc(void *talloc_ctx) +{ + struct sgsn_instance *inst; + inst = talloc_zero(talloc_ctx, struct sgsn_instance); + inst->cfg.gtp_statedir = talloc_strdup(inst, "./"); + inst->cfg.auth_policy = SGSN_AUTH_POLICY_CLOSED; + inst->cfg.require_authentication = true; /* only applies if auth_policy is REMOTE */ + inst->cfg.gsup_server_port = OSMO_GSUP_PORT; + return inst; +} + +void sgsn_inst_init(struct sgsn_instance *sgsn) +{ + osmo_timer_setup(&sgsn->llme_timer, sgsn_llme_check_cb, NULL); + osmo_timer_schedule(&sgsn->llme_timer, GPRS_LLME_CHECK_TICK, 0); +} |