neels has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-hnbgw/+/33177 ) Change subject: cnpool: return Paging Resp to the exact CN link that Paged ...................................................................... cnpool: return Paging Resp to the exact CN link that Paged Implement Paging record, remembering which CN link paged for which mobile identity, for a set time period roundabout 15 seconds. When receiving a Paging Response from a UE, connect it to the CN link that sent the Paging. Related: SYS#6412 Change-Id: I907dbcaeb442ca5630146f8cad40601c448fc40e --- M include/osmocom/hnbgw/hnbgw.h M src/osmo-hnbgw/cnlink.c M src/osmo-hnbgw/hnbgw_cn.c M src/osmo-hnbgw/tdefs.c 4 files changed, 346 insertions(+), 9 deletions(-) git pull ssh://gerrit.osmocom.org:29418/osmo-hnbgw refs/changes/77/33177/1 diff --git a/include/osmocom/hnbgw/hnbgw.h b/include/osmocom/hnbgw/hnbgw.h index 69ce186..ed3cd62 100644 --- a/include/osmocom/hnbgw/hnbgw.h +++ b/include/osmocom/hnbgw/hnbgw.h @@ -180,6 +180,7 @@ bool allow_attach; bool allow_emerg; + struct llist_head paging; struct rate_ctr_group *ctrs; }; diff --git a/src/osmo-hnbgw/cnlink.c b/src/osmo-hnbgw/cnlink.c index 20b5cd9..e1ed757 100644 --- a/src/osmo-hnbgw/cnlink.c +++ b/src/osmo-hnbgw/cnlink.c @@ -87,6 +87,7 @@ }; talloc_steal(cnlink, name); INIT_LLIST_HEAD(&cnlink->map_list); + INIT_LLIST_HEAD(&cnlink->paging); llist_add_tail(&cnlink->entry, &cnpool->cnlinks); LOG_CNLINK(cnlink, DCN, LOGL_DEBUG, "allocated\n"); diff --git a/src/osmo-hnbgw/hnbgw_cn.c b/src/osmo-hnbgw/hnbgw_cn.c index ed2e0ab..dced6c1 100644 --- a/src/osmo-hnbgw/hnbgw_cn.c +++ b/src/osmo-hnbgw/hnbgw_cn.c @@ -23,6 +23,8 @@ #include <arpa/inet.h> #include <errno.h> +#include <asn1c/asn1helpers.h> + #include <osmocom/core/msgb.h> #include <osmocom/core/utils.h> #include <osmocom/core/timer.h> @@ -37,8 +39,10 @@ #include <osmocom/hnbgw/hnbgw.h> #include <osmocom/hnbgw/hnbgw_rua.h> #include <osmocom/hnbgw/hnbgw_cn.h> +#include <osmocom/hnbgw/tdefs.h> #include <osmocom/ranap/ranap_ies_defs.h> #include <osmocom/ranap/ranap_msg_factory.h> +#include <osmocom/ranap/iu_helpers.h> #include <osmocom/hnbgw/context_map.h> /*********************************************************************** @@ -98,25 +102,211 @@ return 0; } +struct cnlink_paging { + struct llist_head entry; + + struct osmo_mobile_identity mi; + struct osmo_mobile_identity mi2; + time_t timestamp; +}; + +static int cnlink_paging_destructor(struct cnlink_paging *p) +{ + llist_del(&p->entry); + return 0; +} + +/* Return current timestamp in *timestamp, and the oldest still valid timestamp according to T3113 timeout. */ +static const char *cnlink_paging_gettime(time_t *timestamp_p, time_t *timeout_p) +{ + struct timespec now; + time_t timestamp; + + /* get timestamp */ + if (osmo_clock_gettime(CLOCK_MONOTONIC, &now) != 0) + return "cannot get timestamp"; + timestamp = now.tv_sec; + + if (timestamp_p) + *timestamp_p = timestamp; + if (timeout_p) + *timeout_p = timestamp - osmo_tdef_get(hnbgw_T_defs, 3113, OSMO_TDEF_S, 15); + return NULL; +} + +static const char *cnlink_paging_add(struct hnbgw_cnlink *cnlink, const struct osmo_mobile_identity *mi, + const struct osmo_mobile_identity *mi2) +{ + struct cnlink_paging *p, *p2; + time_t timestamp; + time_t timeout; + const char *errmsg; + + errmsg = cnlink_paging_gettime(&timestamp, &timeout); + if (errmsg) + return errmsg; + + /* Prune all paging records that are older than the configured timeout. */ + llist_for_each_entry_safe(p, p2, &cnlink->paging, entry) { + if (p->timestamp >= timeout) + continue; + talloc_free(p); + } + + /* Add new entry */ + p = talloc_zero(cnlink, struct cnlink_paging); + *p = (struct cnlink_paging){ + .timestamp = timestamp, + .mi = *mi, + .mi2 = *mi2, + }; + llist_add_tail(&p->entry, &cnlink->paging); + talloc_set_destructor(p, cnlink_paging_destructor); + + LOG_CNLINK(cnlink, DCN, LOGL_INFO, "Rx Paging from CN for %s %s\n", + osmo_mobile_identity_to_str_c(OTC_SELECT, mi), + osmo_mobile_identity_to_str_c(OTC_SELECT, mi2)); + return NULL; +} + +static const char *omi_from_ranap_ue_id(struct osmo_mobile_identity *mi, const RANAP_PermanentNAS_UE_ID_t *ranap_mi) +{ + if (!ranap_mi) + return "null UE ID"; + + if (ranap_mi->present != RANAP_PermanentNAS_UE_ID_PR_iMSI) + return talloc_asprintf(OTC_SELECT, "unsupported UE ID type %u in RANAP Paging", ranap_mi->present); + + if (ranap_mi->choice.iMSI.size > sizeof(mi->imsi)) + return talloc_asprintf(OTC_SELECT, "invalid IMSI size %d > %zu", + ranap_mi->choice.iMSI.size, sizeof(mi->imsi)); + + *mi = (struct osmo_mobile_identity){ + .type = GSM_MI_TYPE_IMSI, + }; + ranap_bcd_decode(mi->imsi, sizeof(mi->imsi), ranap_mi->choice.iMSI.buf, ranap_mi->choice.iMSI.size); + LOGP(DCN, LOGL_DEBUG, "ranap MI %s = %s\n", osmo_hexdump(ranap_mi->choice.iMSI.buf, ranap_mi->choice.iMSI.size), + mi->imsi); + return NULL; +} + +static const char *omi_from_ranap_temp_ue_id(struct osmo_mobile_identity *mi, const RANAP_TemporaryUE_ID_t *ranap_tmsi) +{ + const OCTET_STRING_t *tmsi_str; + + if (!ranap_tmsi) + return "null UE ID"; + + switch (ranap_tmsi->present) { + case RANAP_TemporaryUE_ID_PR_tMSI: + tmsi_str = &ranap_tmsi->choice.tMSI; + break; + case RANAP_TemporaryUE_ID_PR_p_TMSI: + tmsi_str = &ranap_tmsi->choice.p_TMSI; + break; + default: + return talloc_asprintf(OTC_SELECT, "unsupported Temporary UE ID type %u in RANAP Paging", ranap_tmsi->present); + } + + *mi = (struct osmo_mobile_identity){ + .type = GSM_MI_TYPE_TMSI, + .tmsi = asn1str_to_u32(tmsi_str), + }; + LOGP(DCN, LOGL_DEBUG, "ranap temp UE ID = %s\n", osmo_mobile_identity_to_str_c(OTC_SELECT, mi)); + return NULL; +} + +static const char *cnlink_paging_add_ranap(struct hnbgw_cnlink *cnlink, RANAP_InitiatingMessage_t *imsg) +{ + RANAP_PagingIEs_t ies; + struct osmo_mobile_identity mi = {}; + struct osmo_mobile_identity mi2 = {}; + RANAP_CN_DomainIndicator_t domain; + const char *errmsg; + + if (ranap_decode_pagingies(&ies, &imsg->value) < 0) + return "decoding RANAP IEs failed"; + + domain = ies.cN_DomainIndicator; + errmsg = omi_from_ranap_ue_id(&mi, &ies.permanentNAS_UE_ID); + + if (!errmsg && (ies.presenceMask & PAGINGIES_RANAP_TEMPORARYUE_ID_PRESENT)) + errmsg = omi_from_ranap_temp_ue_id(&mi2, &ies.temporaryUE_ID); + + ranap_free_pagingies(&ies); + LOG_CNLINK(cnlink, DCN, LOGL_DEBUG, "Decoded Paging: %s %s %s%s%s\n", + ranap_domain_name(domain), osmo_mobile_identity_to_str_c(OTC_SELECT, &mi), + mi2.type ? osmo_mobile_identity_to_str_c(OTC_SELECT, &mi2) : "-", + errmsg ? " -- MI error: " : "", + errmsg ? : ""); + + if (cnlink->pool->domain != domain) + return talloc_asprintf(OTC_SELECT, "message indicates domain %s, but this is %s on domain %s\n", + ranap_domain_name(domain), cnlink->name, ranap_domain_name(cnlink->pool->domain)); + + if (errmsg) + return errmsg; + + return cnlink_paging_add(cnlink, &mi, &mi2); +} + +/* If this cnlink has a recent Paging for the given MI, return true and drop the Paging record. + * Else return false. */ +static bool cnlink_match_paging_mi(struct hnbgw_cnlink *cnlink, const struct osmo_mobile_identity *mi, time_t timeout) +{ + struct cnlink_paging *p, *p2; + llist_for_each_entry_safe(p, p2, &cnlink->paging, entry) { + if (p->timestamp < timeout) { + talloc_free(p); + continue; + } + if (osmo_mobile_identity_cmp(&p->mi, mi) + && osmo_mobile_identity_cmp(&p->mi2, mi)) + continue; + talloc_free(p); + return true; + } + return false; +} + +static struct hnbgw_cnlink *cnlink_find_by_paging_mi(struct hnbgw_cnpool *cnpool, const struct osmo_mobile_identity *mi) +{ + struct hnbgw_cnlink *cnlink; + time_t timeout = 0; + const char *errmsg; + + errmsg = cnlink_paging_gettime(NULL, &timeout); + if (errmsg) + LOGP(DCN, LOGL_ERROR, "%s\n", errmsg); + + llist_for_each_entry(cnlink, &cnpool->cnlinks, entry) { + if (cnlink_match_paging_mi(cnlink, mi, timeout)) + return cnlink; + } + return NULL; +} + static int cn_ranap_rx_paging_cmd(struct hnbgw_cnlink *cnlink, RANAP_InitiatingMessage_t *imsg, const uint8_t *data, unsigned int len) { + const char *errmsg; struct hnb_context *hnb; - RANAP_PagingIEs_t ies; - int rc; - rc = ranap_decode_pagingies(&ies, &imsg->value); - if (rc < 0) - return rc; + errmsg = cnlink_paging_add_ranap(cnlink, imsg); + if (errmsg) { + LOG_CNLINK(cnlink, DCN, LOGL_ERROR, "Rx Paging from CN: %s. Dropping paging record." + " Later on, the Paging Response may be forwarded to the wrong CN peer.\n", + errmsg); + return -1; + } /* FIXME: determine which HNBs to send this Paging command, * rather than broadcasting to all HNBs */ llist_for_each_entry(hnb, &g_hnbgw->hnb_list, list) { - rc = rua_tx_udt(hnb, data, len); + rua_tx_udt(hnb, data, len); } - ranap_free_pagingies(&ies); return 0; } @@ -314,6 +504,122 @@ return map_sccp_dispatch(map, MAP_SCCP_EV_RX_RELEASED, oph->msg); } +static struct hnbgw_cnlink *_cnlink_find_by_remote_pc(struct hnbgw_cnpool *cnpool, struct osmo_ss7_instance *cs7, uint32_t pc) +{ + struct hnbgw_cnlink *cnlink; + llist_for_each_entry(cnlink, &cnpool->cnlinks, entry) { + if (!cnlink->hnbgw_sccp_user) + continue; + if (cnlink->hnbgw_sccp_user->ss7 != cs7) + continue; + if ((cnlink->remote_addr.presence & OSMO_SCCP_ADDR_T_PC) == 0) + continue; + if (cnlink->remote_addr.pc != pc) + continue; + return cnlink; + } + return NULL; +} + +/* Find a cnlink by its remote sigtran point code on a given cs7 instance. */ +static struct hnbgw_cnlink *cnlink_find_by_remote_pc(struct osmo_ss7_instance *cs7, uint32_t pc) +{ + struct hnbgw_cnlink *cnlink; + cnlink = _cnlink_find_by_remote_pc(&g_hnbgw->sccp.cnpool_iucs, cs7, pc); + if (!cnlink) + cnlink = _cnlink_find_by_remote_pc(&g_hnbgw->sccp.cnpool_iups, cs7, pc); + return cnlink; +} + +static void handle_pcstate_ind(struct hnbgw_sccp_user *hsu, const struct osmo_scu_pcstate_param *pcst) +{ + struct hnbgw_cnlink *cnlink; + bool connected; + bool disconnected; + struct osmo_ss7_instance *cs7 = hsu->ss7; + + LOGP(DCN, LOGL_DEBUG, "N-PCSTATE ind: affected_pc=%u sp_status=%s remote_sccp_status=%s\n", + pcst->affected_pc, osmo_sccp_sp_status_name(pcst->sp_status), + osmo_sccp_rem_sccp_status_name(pcst->remote_sccp_status)); + + /* If we don't care about that point-code, ignore PCSTATE. */ + cnlink = cnlink_find_by_remote_pc(cs7, pcst->affected_pc); + if (!cnlink) + return; + + /* See if this marks the point code to have become available, or to have been lost. + * + * I want to detect two events: + * - connection event (both indicators say PC is reachable). + * - disconnection event (at least one indicator says the PC is not reachable). + * + * There are two separate incoming indicators with various possible values -- the incoming events can be: + * + * - neither connection nor disconnection indicated -- just indicating congestion + * connected == false, disconnected == false --> do nothing. + * - both incoming values indicate that we are connected + * --> trigger connected + * - both indicate we are disconnected + * --> trigger disconnected + * - one value indicates 'connected', the other indicates 'disconnected' + * --> trigger disconnected + * + * Congestion could imply that we're connected, but it does not indicate that a PC's reachability changed, so no need to + * trigger on that. + */ + connected = false; + disconnected = false; + + switch (pcst->sp_status) { + case OSMO_SCCP_SP_S_ACCESSIBLE: + connected = true; + break; + case OSMO_SCCP_SP_S_INACCESSIBLE: + disconnected = true; + break; + default: + case OSMO_SCCP_SP_S_CONGESTED: + /* Neither connecting nor disconnecting */ + break; + } + + switch (pcst->remote_sccp_status) { + case OSMO_SCCP_REM_SCCP_S_AVAILABLE: + if (!disconnected) + connected = true; + break; + case OSMO_SCCP_REM_SCCP_S_UNAVAILABLE_UNKNOWN: + case OSMO_SCCP_REM_SCCP_S_UNEQUIPPED: + case OSMO_SCCP_REM_SCCP_S_INACCESSIBLE: + disconnected = true; + connected = false; + break; + default: + case OSMO_SCCP_REM_SCCP_S_CONGESTED: + /* Neither connecting nor disconnecting */ + break; + } + + if (disconnected && cnlink_is_conn_ready(cnlink)) { + LOG_CNLINK(cnlink, DCN, LOGL_NOTICE, + "now unreachable: N-PCSTATE ind: pc=%u sp_status=%s remote_sccp_status=%s\n", + pcst->affected_pc, + osmo_sccp_sp_status_name(pcst->sp_status), + osmo_sccp_rem_sccp_status_name(pcst->remote_sccp_status)); + /* A previously usable cnlink has disconnected. Kick it back to DISC state. */ + cnlink_set_disconnected(cnlink); + } else if (connected && !cnlink_is_conn_ready(cnlink)) { + LOG_CNLINK(cnlink, DCN, LOGL_NOTICE, + "now available: N-PCSTATE ind: pc=%u sp_status=%s remote_sccp_status=%s\n", + pcst->affected_pc, + osmo_sccp_sp_status_name(pcst->sp_status), + osmo_sccp_rem_sccp_status_name(pcst->remote_sccp_status)); + /* A previously unusable cnlink has become reachable. Trigger immediate RANAP RESET -- we would resend a + * RESET either way, but we might as well do it now to speed up connecting. */ + cnlink_resend_reset(cnlink); + } +} + /* Entry point for primitives coming up from SCCP User SAP */ static int sccp_sap_up(struct osmo_prim_hdr *oph, void *ctx) { @@ -355,9 +661,9 @@ rc = handle_cn_disc_ind(hsu, &prim->u.disconnect, oph); break; case OSMO_PRIM(OSMO_SCU_PRIM_N_PCSTATE, PRIM_OP_INDICATION): - LOGP(DCN, LOGL_DEBUG, "Ignoring prim %s from SCCP USER SAP\n", - osmo_scu_prim_hdr_name_c(OTC_SELECT, oph)); + handle_pcstate_ind(hsu, &prim->u.pcstate); break; + default: LOGP(DCN, LOGL_ERROR, "Received unknown prim %u from SCCP USER SAP\n", @@ -678,6 +984,18 @@ bool is_null_nri = false; uint8_t nri_bitlen = cnpool->use.nri_bitlen; + /* Match IMSI with previous Paging */ + if (map->l3.gsm48_msg_type == GSM48_MT_RR_PAG_RESP) { + cnlink = cnlink_find_by_paging_mi(cnpool, &map->l3.mi); + if (cnlink) { + LOG_MAP(map, DCN, LOGL_INFO, "CN link paging record selects %s %d\n", cnpool->peer_name, + cnlink->nr); + rate_ctr_inc(rate_ctr_group_get_ctr(cnlink->ctrs, CNLINK_CTR_CNPOOL_SUBSCR_PAGED)); + return cnlink; + } + /* If there is no match, go on with other ways */ + } + #define LOG_NRI(LOGLEVEL, FORMAT, ARGS...) \ LOG_MAP(map, DCN, LOGLEVEL, "%s NRI(%dbit)=0x%x=%d: " FORMAT, osmo_mobile_identity_to_str_c(OTC_SELECT, &map->l3.mi), \ nri_bitlen, nri_v, nri_v, ##ARGS) diff --git a/src/osmo-hnbgw/tdefs.c b/src/osmo-hnbgw/tdefs.c index 992c140..601f704 100644 --- a/src/osmo-hnbgw/tdefs.c +++ b/src/osmo-hnbgw/tdefs.c @@ -32,6 +32,7 @@ }; struct osmo_tdef hnbgw_T_defs[] = { + {.T = 3113, .default_val = 15, .desc = "Time to keep Paging record, for CN pools with more than one link" }, {.T = 4, .default_val = 5, .desc = "Timeout to receive RANAP RESET ACKNOWLEDGE from an MSC/SGSN" }, {.T = -31, .default_val = 5, .desc = "Timeout for discarding a partially released context map (RUA <-> SCCP)" }, {.T = -1002, .default_val = 10, .desc = "Timeout for the HNB to respond to PS RAB Assignment Request" }, -- To view, visit https://gerrit.osmocom.org/c/osmo-hnbgw/+/33177 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: osmo-hnbgw Gerrit-Branch: master Gerrit-Change-Id: I907dbcaeb442ca5630146f8cad40601c448fc40e Gerrit-Change-Number: 33177 Gerrit-PatchSet: 1 Gerrit-Owner: neels &lt;nhofmeyr(a)sysmocom.de&gt; Gerrit-MessageType: newchange