| /* GPRS Networks Service (NS) messages on the Gb interfacebvci = msgb_bvci(msg); |
| * 3GPP TS 08.16 version 8.0.1 Release 1999 / ETSI TS 101 299 V8.0.1 (2002-05) */ |
| |
| /* (C) 2009-2010 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 General Public License as published by |
| * the Free Software Foundation; either version 2 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 General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| */ |
| |
| /* Some introduction into NS: NS is used typically on top of frame relay, |
| * but in the ip.access world it is encapsulated in UDP packets. It serves |
| * as an intermediate shim betwen BSSGP and the underlying medium. It doesn't |
| * do much, apart from providing congestion notification and status indication. |
| * |
| * Terms: |
| * NS Network Service |
| * NSVC NS Virtual Connection |
| * NSEI NS Entity Identifier |
| * NSVL NS Virtual Link |
| * NSVLI NS Virtual Link Identifier |
| * BVC BSSGP Virtual Connection |
| * BVCI BSSGP Virtual Connection Identifier |
| * NSVCG NS Virtual Connection Goup |
| * Blocked NS-VC cannot be used for user traffic |
| * Alive Ability of a NS-VC to provide communication |
| * |
| * There can be multiple BSSGP virtual connections over one (group of) NSVC's. BSSGP will |
| * therefore identify the BSSGP virtual connection by a BVCI passed down to NS. |
| * NS then has to firgure out which NSVC's are responsible for this BVCI. |
| * Those mappings are administratively configured. |
| */ |
| |
| /* This implementation has the following limitations: |
| * o Only one NS-VC for each NSE: No load-sharing function |
| * o NSVCI 65535 and 65534 are reserved for internal use |
| * o Only UDP is supported as of now, no frame relay support |
| * o The IP Sub-Network-Service (SNS) as specified in 48.016 is not implemented |
| * o There are no BLOCK and UNBLOCK timers (yet?) |
| */ |
| |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <errno.h> |
| #include <stdint.h> |
| |
| #include <arpa/inet.h> |
| |
| #include <openbsc/gsm_data.h> |
| #include <osmocore/msgb.h> |
| #include <osmocore/tlv.h> |
| #include <osmocore/talloc.h> |
| #include <osmocore/select.h> |
| #include <osmocore/rate_ctr.h> |
| #include <openbsc/debug.h> |
| #include <openbsc/signal.h> |
| #include <openbsc/gprs_ns.h> |
| #include <openbsc/gprs_bssgp.h> |
| #include <openbsc/gprs_ns_frgre.h> |
| #include <openbsc/socket.h> |
| |
| static const struct tlv_definition ns_att_tlvdef = { |
| .def = { |
| [NS_IE_CAUSE] = { TLV_TYPE_TvLV, 0 }, |
| [NS_IE_VCI] = { TLV_TYPE_TvLV, 0 }, |
| [NS_IE_PDU] = { TLV_TYPE_TvLV, 0 }, |
| [NS_IE_BVCI] = { TLV_TYPE_TvLV, 0 }, |
| [NS_IE_NSEI] = { TLV_TYPE_TvLV, 0 }, |
| }, |
| }; |
| |
| enum ns_ctr { |
| NS_CTR_PKTS_IN, |
| NS_CTR_PKTS_OUT, |
| NS_CTR_BYTES_IN, |
| NS_CTR_BYTES_OUT, |
| NS_CTR_BLOCKED, |
| NS_CTR_DEAD, |
| }; |
| |
| static const struct rate_ctr_desc nsvc_ctr_description[] = { |
| { "packets.in", "Packets at NS Level ( In)" }, |
| { "packets.out","Packets at NS Level (Out)" }, |
| { "bytes.in", "Bytes at NS Level ( In)" }, |
| { "bytes.out", "Bytes at NS Level (Out)" }, |
| { "blocked", "NS-VC Block count " }, |
| { "dead", "NS-VC gone dead count " }, |
| }; |
| |
| static const struct rate_ctr_group_desc nsvc_ctrg_desc = { |
| .group_name_prefix = "ns.nsvc", |
| .group_description = "NSVC Peer Statistics", |
| .num_ctr = ARRAY_SIZE(nsvc_ctr_description), |
| .ctr_desc = nsvc_ctr_description, |
| }; |
| |
| /* Lookup struct gprs_nsvc based on NSVCI */ |
| struct gprs_nsvc *nsvc_by_nsvci(struct gprs_ns_inst *nsi, uint16_t nsvci) |
| { |
| struct gprs_nsvc *nsvc; |
| llist_for_each_entry(nsvc, &nsi->gprs_nsvcs, list) { |
| if (nsvc->nsvci == nsvci) |
| return nsvc; |
| } |
| return NULL; |
| } |
| |
| /* Lookup struct gprs_nsvc based on NSVCI */ |
| struct gprs_nsvc *nsvc_by_nsei(struct gprs_ns_inst *nsi, uint16_t nsei) |
| { |
| struct gprs_nsvc *nsvc; |
| llist_for_each_entry(nsvc, &nsi->gprs_nsvcs, list) { |
| if (nsvc->nsei == nsei) |
| return nsvc; |
| } |
| return NULL; |
| } |
| |
| /* Lookup struct gprs_nsvc based on remote peer socket addr */ |
| static struct gprs_nsvc *nsvc_by_rem_addr(struct gprs_ns_inst *nsi, |
| struct sockaddr_in *sin) |
| { |
| struct gprs_nsvc *nsvc; |
| llist_for_each_entry(nsvc, &nsi->gprs_nsvcs, list) { |
| if (nsvc->ip.bts_addr.sin_addr.s_addr == |
| sin->sin_addr.s_addr && |
| nsvc->ip.bts_addr.sin_port == sin->sin_port) |
| return nsvc; |
| } |
| return NULL; |
| } |
| |
| static void gprs_ns_timer_cb(void *data); |
| |
| struct gprs_nsvc *nsvc_create(struct gprs_ns_inst *nsi, uint16_t nsvci) |
| { |
| struct gprs_nsvc *nsvc; |
| |
| LOGP(DNS, LOGL_INFO, "NSVCI=%u Creating NS-VC\n", nsvci); |
| |
| nsvc = talloc_zero(nsi, struct gprs_nsvc); |
| nsvc->nsvci = nsvci; |
| /* before RESET procedure: BLOCKED and DEAD */ |
| nsvc->state = NSE_S_BLOCKED; |
| nsvc->nsi = nsi; |
| nsvc->timer.cb = gprs_ns_timer_cb; |
| nsvc->timer.data = nsvc; |
| nsvc->ctrg = rate_ctr_group_alloc(nsvc, &nsvc_ctrg_desc, nsvci); |
| |
| llist_add(&nsvc->list, &nsi->gprs_nsvcs); |
| |
| return nsvc; |
| } |
| |
| void nsvc_delete(struct gprs_nsvc *nsvc) |
| { |
| if (bsc_timer_pending(&nsvc->timer)) |
| bsc_del_timer(&nsvc->timer); |
| llist_del(&nsvc->list); |
| talloc_free(nsvc); |
| } |
| |
| static void ns_dispatch_signal(struct gprs_nsvc *nsvc, unsigned int signal, |
| uint8_t cause) |
| { |
| struct ns_signal_data nssd; |
| |
| nssd.nsvc = nsvc; |
| nssd.cause = cause; |
| |
| dispatch_signal(SS_NS, signal, &nssd); |
| } |
| |
| /* Section 10.3.2, Table 13 */ |
| static const struct value_string ns_cause_str[] = { |
| { NS_CAUSE_TRANSIT_FAIL, "Transit network failure" }, |
| { NS_CAUSE_OM_INTERVENTION, "O&M intervention" }, |
| { NS_CAUSE_EQUIP_FAIL, "Equipment failure" }, |
| { NS_CAUSE_NSVC_BLOCKED, "NS-VC blocked" }, |
| { NS_CAUSE_NSVC_UNKNOWN, "NS-VC unknown" }, |
| { NS_CAUSE_BVCI_UNKNOWN, "BVCI unknown" }, |
| { NS_CAUSE_SEM_INCORR_PDU, "Semantically incorrect PDU" }, |
| { NS_CAUSE_PDU_INCOMP_PSTATE, "PDU not compatible with protocol state" }, |
| { NS_CAUSE_PROTO_ERR_UNSPEC, "Protocol error, unspecified" }, |
| { NS_CAUSE_INVAL_ESSENT_IE, "Invalid essential IE" }, |
| { NS_CAUSE_MISSING_ESSENT_IE, "Missing essential IE" }, |
| { 0, NULL } |
| }; |
| |
| const char *gprs_ns_cause_str(enum ns_cause cause) |
| { |
| return get_value_string(ns_cause_str, cause); |
| } |
| |
| static int nsip_sendmsg(struct gprs_nsvc *nsvc, struct msgb *msg); |
| extern int grps_ns_frgre_sendmsg(struct gprs_nsvc *nsvc, struct msgb *msg); |
| |
| static int gprs_ns_tx(struct gprs_nsvc *nsvc, struct msgb *msg) |
| { |
| int ret; |
| |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| |
| /* Increment number of Uplink bytes */ |
| rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_PKTS_OUT]); |
| rate_ctr_add(&nsvc->ctrg->ctr[NS_CTR_BYTES_OUT], msgb_l2len(msg)); |
| |
| switch (nsvc->ll) { |
| case GPRS_NS_LL_UDP: |
| ret = nsip_sendmsg(nsvc, msg); |
| break; |
| case GPRS_NS_LL_FR_GRE: |
| ret = gprs_ns_frgre_sendmsg(nsvc, msg); |
| break; |
| default: |
| LOGP(DNS, LOGL_ERROR, "unsupported NS linklayer %u\n", nsvc->ll); |
| msgb_free(msg); |
| ret = -EIO; |
| break; |
| } |
| return ret; |
| } |
| |
| static int gprs_ns_tx_simple(struct gprs_nsvc *nsvc, uint8_t pdu_type) |
| { |
| struct msgb *msg = gprs_ns_msgb_alloc(); |
| struct gprs_ns_hdr *nsh; |
| |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| |
| if (!msg) |
| return -ENOMEM; |
| |
| msg->l2h = msgb_put(msg, sizeof(*nsh)); |
| nsh = (struct gprs_ns_hdr *) msg->l2h; |
| |
| nsh->pdu_type = pdu_type; |
| |
| return gprs_ns_tx(nsvc, msg); |
| } |
| |
| int gprs_ns_tx_reset(struct gprs_nsvc *nsvc, uint8_t cause) |
| { |
| struct msgb *msg = gprs_ns_msgb_alloc(); |
| struct gprs_ns_hdr *nsh; |
| uint16_t nsvci = htons(nsvc->nsvci); |
| uint16_t nsei = htons(nsvc->nsei); |
| |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| |
| if (!msg) |
| return -ENOMEM; |
| |
| LOGP(DNS, LOGL_INFO, "NSEI=%u Tx NS RESET (NSVCI=%u, cause=%s)\n", |
| nsvc->nsei, nsvc->nsvci, gprs_ns_cause_str(cause)); |
| |
| msg->l2h = msgb_put(msg, sizeof(*nsh)); |
| nsh = (struct gprs_ns_hdr *) msg->l2h; |
| nsh->pdu_type = NS_PDUT_RESET; |
| |
| msgb_tvlv_put(msg, NS_IE_CAUSE, 1, &cause); |
| msgb_tvlv_put(msg, NS_IE_VCI, 2, (uint8_t *) &nsvci); |
| msgb_tvlv_put(msg, NS_IE_NSEI, 2, (uint8_t *) &nsei); |
| |
| return gprs_ns_tx(nsvc, msg); |
| |
| } |
| |
| int gprs_ns_tx_status(struct gprs_nsvc *nsvc, uint8_t cause, |
| uint16_t bvci, struct msgb *orig_msg) |
| { |
| struct msgb *msg = gprs_ns_msgb_alloc(); |
| struct gprs_ns_hdr *nsh; |
| uint16_t nsvci = htons(nsvc->nsvci); |
| |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| |
| bvci = htons(bvci); |
| |
| if (!msg) |
| return -ENOMEM; |
| |
| LOGP(DNS, LOGL_NOTICE, "NSEI=%u Tx NS STATUS (NSVCI=%u, cause=%s)\n", |
| nsvc->nsei, nsvc->nsvci, gprs_ns_cause_str(cause)); |
| |
| msg->l2h = msgb_put(msg, sizeof(*nsh)); |
| nsh = (struct gprs_ns_hdr *) msg->l2h; |
| nsh->pdu_type = NS_PDUT_STATUS; |
| |
| msgb_tvlv_put(msg, NS_IE_CAUSE, 1, &cause); |
| |
| /* Section 9.2.7.1: Static conditions for NS-VCI */ |
| if (cause == NS_CAUSE_NSVC_BLOCKED || |
| cause == NS_CAUSE_NSVC_UNKNOWN) |
| msgb_tvlv_put(msg, NS_IE_VCI, 2, (uint8_t *)&nsvci); |
| |
| /* Section 9.2.7.2: Static conditions for NS PDU */ |
| switch (cause) { |
| case NS_CAUSE_SEM_INCORR_PDU: |
| case NS_CAUSE_PDU_INCOMP_PSTATE: |
| case NS_CAUSE_PROTO_ERR_UNSPEC: |
| case NS_CAUSE_INVAL_ESSENT_IE: |
| case NS_CAUSE_MISSING_ESSENT_IE: |
| msgb_tvlv_put(msg, NS_IE_PDU, msgb_l2len(orig_msg), |
| orig_msg->l2h); |
| break; |
| default: |
| break; |
| } |
| |
| /* Section 9.2.7.3: Static conditions for BVCI */ |
| if (cause == NS_CAUSE_BVCI_UNKNOWN) |
| msgb_tvlv_put(msg, NS_IE_VCI, 2, (uint8_t *)&bvci); |
| |
| return gprs_ns_tx(nsvc, msg); |
| } |
| |
| int gprs_ns_tx_block(struct gprs_nsvc *nsvc, uint8_t cause) |
| { |
| struct msgb *msg = gprs_ns_msgb_alloc(); |
| struct gprs_ns_hdr *nsh; |
| uint16_t nsvci = htons(nsvc->nsvci); |
| |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| |
| if (!msg) |
| return -ENOMEM; |
| |
| LOGP(DNS, LOGL_INFO, "NSEI=%u Tx NS BLOCK (NSVCI=%u, cause=%s)\n", |
| nsvc->nsei, nsvc->nsvci, gprs_ns_cause_str(cause)); |
| |
| /* be conservative and mark it as blocked even now! */ |
| nsvc->state |= NSE_S_BLOCKED; |
| rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_BLOCKED]); |
| |
| msg->l2h = msgb_put(msg, sizeof(*nsh)); |
| nsh = (struct gprs_ns_hdr *) msg->l2h; |
| nsh->pdu_type = NS_PDUT_BLOCK; |
| |
| msgb_tvlv_put(msg, NS_IE_CAUSE, 1, &cause); |
| msgb_tvlv_put(msg, NS_IE_VCI, 2, (uint8_t *) &nsvci); |
| |
| return gprs_ns_tx(nsvc, msg); |
| } |
| |
| int gprs_ns_tx_unblock(struct gprs_nsvc *nsvc) |
| { |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| LOGP(DNS, LOGL_INFO, "NSEI=%u Tx NS UNBLOCK (NSVCI=%u)\n", |
| nsvc->nsei, nsvc->nsvci); |
| |
| return gprs_ns_tx_simple(nsvc, NS_PDUT_UNBLOCK); |
| } |
| |
| int gprs_ns_tx_alive(struct gprs_nsvc *nsvc) |
| { |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| LOGP(DNS, LOGL_DEBUG, "NSEI=%u Tx NS ALIVE (NSVCI=%u)\n", |
| nsvc->nsei, nsvc->nsvci); |
| |
| return gprs_ns_tx_simple(nsvc, NS_PDUT_ALIVE); |
| } |
| |
| int gprs_ns_tx_alive_ack(struct gprs_nsvc *nsvc) |
| { |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| LOGP(DNS, LOGL_DEBUG, "NSEI=%u Tx NS ALIVE_ACK (NSVCI=%u)\n", |
| nsvc->nsei, nsvc->nsvci); |
| |
| return gprs_ns_tx_simple(nsvc, NS_PDUT_ALIVE_ACK); |
| } |
| |
| static const enum ns_timeout timer_mode_tout[_NSVC_TIMER_NR] = { |
| [NSVC_TIMER_TNS_RESET] = NS_TOUT_TNS_RESET, |
| [NSVC_TIMER_TNS_ALIVE] = NS_TOUT_TNS_ALIVE, |
| [NSVC_TIMER_TNS_TEST] = NS_TOUT_TNS_TEST, |
| }; |
| |
| static const struct value_string timer_mode_strs[] = { |
| { NSVC_TIMER_TNS_RESET, "tns-reset" }, |
| { NSVC_TIMER_TNS_ALIVE, "tns-alive" }, |
| { NSVC_TIMER_TNS_TEST, "tns-test" }, |
| { 0, NULL } |
| }; |
| |
| static void nsvc_start_timer(struct gprs_nsvc *nsvc, enum nsvc_timer_mode mode) |
| { |
| enum ns_timeout tout = timer_mode_tout[mode]; |
| unsigned int seconds = nsvc->nsi->timeout[tout]; |
| |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| DEBUGP(DNS, "NSEI=%u Starting timer in mode %s (%u seconds)\n", |
| nsvc->nsei, get_value_string(timer_mode_strs, mode), |
| seconds); |
| |
| if (bsc_timer_pending(&nsvc->timer)) |
| bsc_del_timer(&nsvc->timer); |
| |
| nsvc->timer_mode = mode; |
| bsc_schedule_timer(&nsvc->timer, seconds, 0); |
| } |
| |
| static void gprs_ns_timer_cb(void *data) |
| { |
| struct gprs_nsvc *nsvc = data; |
| enum ns_timeout tout = timer_mode_tout[nsvc->timer_mode]; |
| unsigned int seconds = nsvc->nsi->timeout[tout]; |
| |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| DEBUGP(DNS, "NSEI=%u Timer expired in mode %s (%u seconds)\n", |
| nsvc->nsei, get_value_string(timer_mode_strs, nsvc->timer_mode), |
| seconds); |
| |
| switch (nsvc->timer_mode) { |
| case NSVC_TIMER_TNS_ALIVE: |
| /* Tns-alive case: we expired without response ! */ |
| nsvc->alive_retries++; |
| if (nsvc->alive_retries > |
| nsvc->nsi->timeout[NS_TOUT_TNS_ALIVE_RETRIES]) { |
| /* mark as dead and blocked */ |
| nsvc->state = NSE_S_BLOCKED; |
| rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_BLOCKED]); |
| rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_DEAD]); |
| LOGP(DNS, LOGL_NOTICE, |
| "NSEI=%u Tns-alive expired more then " |
| "%u times, blocking NS-VC\n", nsvc->nsei, |
| nsvc->nsi->timeout[NS_TOUT_TNS_ALIVE_RETRIES]); |
| ns_dispatch_signal(nsvc, S_NS_ALIVE_EXP, 0); |
| ns_dispatch_signal(nsvc, S_NS_BLOCK, NS_CAUSE_NSVC_BLOCKED); |
| return; |
| } |
| /* Tns-test case: send NS-ALIVE PDU */ |
| gprs_ns_tx_alive(nsvc); |
| /* start Tns-alive timer */ |
| nsvc_start_timer(nsvc, NSVC_TIMER_TNS_ALIVE); |
| break; |
| case NSVC_TIMER_TNS_TEST: |
| /* Tns-test case: send NS-ALIVE PDU */ |
| gprs_ns_tx_alive(nsvc); |
| /* start Tns-alive timer (transition into faster |
| * alive retransmissions) */ |
| nsvc->alive_retries = 0; |
| nsvc_start_timer(nsvc, NSVC_TIMER_TNS_ALIVE); |
| break; |
| case NSVC_TIMER_TNS_RESET: |
| /* Chapter 7.3: Re-send the RESET */ |
| gprs_ns_tx_reset(nsvc, NS_CAUSE_OM_INTERVENTION); |
| /* Re-start Tns-reset timer */ |
| nsvc_start_timer(nsvc, NSVC_TIMER_TNS_RESET); |
| break; |
| case _NSVC_TIMER_NR: |
| break; |
| } |
| } |
| |
| /* Section 9.2.6 */ |
| static int gprs_ns_tx_reset_ack(struct gprs_nsvc *nsvc) |
| { |
| struct msgb *msg = gprs_ns_msgb_alloc(); |
| struct gprs_ns_hdr *nsh; |
| uint16_t nsvci, nsei; |
| |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| if (!msg) |
| return -ENOMEM; |
| |
| nsvci = htons(nsvc->nsvci); |
| nsei = htons(nsvc->nsei); |
| |
| msg->l2h = msgb_put(msg, sizeof(*nsh)); |
| nsh = (struct gprs_ns_hdr *) msg->l2h; |
| |
| nsh->pdu_type = NS_PDUT_RESET_ACK; |
| |
| LOGP(DNS, LOGL_INFO, "NSEI=%u Tx NS RESET ACK (NSVCI=%u)\n", |
| nsvc->nsei, nsvc->nsvci); |
| |
| msgb_tvlv_put(msg, NS_IE_VCI, 2, (uint8_t *)&nsvci); |
| msgb_tvlv_put(msg, NS_IE_NSEI, 2, (uint8_t *)&nsei); |
| |
| return gprs_ns_tx(nsvc, msg); |
| } |
| |
| /* Section 9.2.10: transmit side / NS-UNITDATA-REQUEST primitive */ |
| int gprs_ns_sendmsg(struct gprs_ns_inst *nsi, struct msgb *msg) |
| { |
| struct gprs_nsvc *nsvc; |
| struct gprs_ns_hdr *nsh; |
| uint16_t bvci = msgb_bvci(msg); |
| |
| nsvc = nsvc_by_nsei(nsi, msgb_nsei(msg)); |
| if (!nsvc) { |
| LOGP(DNS, LOGL_ERROR, "Unable to resolve NSEI %u " |
| "to NS-VC!\n", msgb_nsei(msg)); |
| return -EINVAL; |
| } |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| |
| if (!(nsvc->state & NSE_S_ALIVE)) { |
| LOGP(DNS, LOGL_ERROR, "NSEI=%u is not alive, cannot send\n", |
| nsvc->nsei); |
| return -EBUSY; |
| } |
| if (nsvc->state & NSE_S_BLOCKED) { |
| LOGP(DNS, LOGL_ERROR, "NSEI=%u is blocked, cannot send\n", |
| nsvc->nsei); |
| return -EBUSY; |
| } |
| |
| msg->l2h = msgb_push(msg, sizeof(*nsh) + 3); |
| nsh = (struct gprs_ns_hdr *) msg->l2h; |
| if (!nsh) { |
| LOGP(DNS, LOGL_ERROR, "Not enough headroom for NS header\n"); |
| return -EIO; |
| } |
| |
| nsh->pdu_type = NS_PDUT_UNITDATA; |
| /* spare octet in data[0] */ |
| nsh->data[1] = bvci >> 8; |
| nsh->data[2] = bvci & 0xff; |
| |
| return gprs_ns_tx(nsvc, msg); |
| } |
| |
| /* Section 9.2.10: receive side */ |
| static int gprs_ns_rx_unitdata(struct gprs_nsvc *nsvc, struct msgb *msg) |
| { |
| struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *)msg->l2h; |
| uint16_t bvci; |
| |
| if (nsvc->state & NSE_S_BLOCKED) |
| return gprs_ns_tx_status(nsvc, NS_CAUSE_NSVC_BLOCKED, |
| 0, msg); |
| |
| /* spare octet in data[0] */ |
| bvci = nsh->data[1] << 8 | nsh->data[2]; |
| msgb_bssgph(msg) = &nsh->data[3]; |
| msgb_bvci(msg) = bvci; |
| |
| /* call upper layer (BSSGP) */ |
| return nsvc->nsi->cb(GPRS_NS_EVT_UNIT_DATA, nsvc, msg, bvci); |
| } |
| |
| /* Section 9.2.7 */ |
| static int gprs_ns_rx_status(struct gprs_nsvc *nsvc, struct msgb *msg) |
| { |
| struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *) msg->l2h; |
| struct tlv_parsed tp; |
| uint8_t cause; |
| int rc; |
| |
| LOGP(DNS, LOGL_NOTICE, "NSEI=%u Rx NS STATUS ", nsvc->nsei); |
| |
| rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data, |
| msgb_l2len(msg) - sizeof(*nsh), 0, 0); |
| if (rc < 0) { |
| LOGPC(DNS, LOGL_NOTICE, "Error during TLV Parse\n"); |
| LOGP(DNS, LOGL_ERROR, "NSEI=%u Rx NS STATUS: " |
| "Error during TLV Parse\n", nsvc->nsei); |
| return rc; |
| } |
| |
| if (!TLVP_PRESENT(&tp, NS_IE_CAUSE)) { |
| LOGPC(DNS, LOGL_INFO, "missing cause IE\n"); |
| return -EINVAL; |
| } |
| |
| cause = *TLVP_VAL(&tp, NS_IE_CAUSE); |
| LOGPC(DNS, LOGL_NOTICE, "cause=%s\n", gprs_ns_cause_str(cause)); |
| |
| return 0; |
| } |
| |
| /* Section 7.3 */ |
| static int gprs_ns_rx_reset(struct gprs_nsvc *nsvc, struct msgb *msg) |
| { |
| struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *) msg->l2h; |
| struct tlv_parsed tp; |
| uint8_t *cause; |
| uint16_t *nsvci, *nsei; |
| int rc; |
| |
| rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data, |
| msgb_l2len(msg) - sizeof(*nsh), 0, 0); |
| if (rc < 0) { |
| LOGP(DNS, LOGL_ERROR, "NSEI=%u Rx NS RESET " |
| "Error during TLV Parse\n", nsvc->nsei); |
| return rc; |
| } |
| |
| if (!TLVP_PRESENT(&tp, NS_IE_CAUSE) || |
| !TLVP_PRESENT(&tp, NS_IE_VCI) || |
| !TLVP_PRESENT(&tp, NS_IE_NSEI)) { |
| LOGP(DNS, LOGL_ERROR, "NS RESET Missing mandatory IE\n"); |
| gprs_ns_tx_status(nsvc, NS_CAUSE_MISSING_ESSENT_IE, 0, msg); |
| return -EINVAL; |
| } |
| |
| cause = (uint8_t *) TLVP_VAL(&tp, NS_IE_CAUSE); |
| nsvci = (uint16_t *) TLVP_VAL(&tp, NS_IE_VCI); |
| nsei = (uint16_t *) TLVP_VAL(&tp, NS_IE_NSEI); |
| |
| LOGP(DNS, LOGL_INFO, "NSEI=%u Rx NS RESET (NSVCI=%u, cause=%s)\n", |
| nsvc->nsvci, nsvc->nsei, gprs_ns_cause_str(*cause)); |
| |
| /* Mark NS-VC as blocked and alive */ |
| nsvc->state = NSE_S_BLOCKED | NSE_S_ALIVE; |
| |
| nsvc->nsei = ntohs(*nsei); |
| nsvc->nsvci = ntohs(*nsvci); |
| |
| /* start the test procedure */ |
| gprs_ns_tx_simple(nsvc, NS_PDUT_ALIVE); |
| nsvc_start_timer(nsvc, NSVC_TIMER_TNS_TEST); |
| |
| /* inform interested parties about the fact that this NSVC |
| * has received RESET */ |
| ns_dispatch_signal(nsvc, S_NS_RESET, *cause); |
| |
| return gprs_ns_tx_reset_ack(nsvc); |
| } |
| |
| static int gprs_ns_rx_block(struct gprs_nsvc *nsvc, struct msgb *msg) |
| { |
| struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *) msg->l2h; |
| struct tlv_parsed tp; |
| uint8_t *cause; |
| int rc; |
| |
| LOGP(DNS, LOGL_INFO, "NSEI=%u Rx NS BLOCK\n", nsvc->nsei); |
| |
| nsvc->state |= NSE_S_BLOCKED; |
| |
| rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data, |
| msgb_l2len(msg) - sizeof(*nsh), 0, 0); |
| if (rc < 0) { |
| LOGP(DNS, LOGL_ERROR, "NSEI=%u Rx NS BLOCK " |
| "Error during TLV Parse\n", nsvc->nsei); |
| return rc; |
| } |
| |
| if (!TLVP_PRESENT(&tp, NS_IE_CAUSE) || |
| !TLVP_PRESENT(&tp, NS_IE_VCI)) { |
| LOGP(DNS, LOGL_ERROR, "NS RESET Missing mandatory IE\n"); |
| gprs_ns_tx_status(nsvc, NS_CAUSE_MISSING_ESSENT_IE, 0, msg); |
| return -EINVAL; |
| } |
| |
| cause = (uint8_t *) TLVP_VAL(&tp, NS_IE_CAUSE); |
| //nsvci = (uint16_t *) TLVP_VAL(&tp, NS_IE_VCI); |
| |
| ns_dispatch_signal(nsvc, S_NS_BLOCK, *cause); |
| rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_BLOCKED]); |
| |
| return gprs_ns_tx_simple(nsvc, NS_PDUT_BLOCK_ACK); |
| } |
| |
| /* main entry point, here incoming NS frames enter */ |
| int gprs_ns_rcvmsg(struct gprs_ns_inst *nsi, struct msgb *msg, |
| struct sockaddr_in *saddr, enum gprs_ns_ll ll) |
| { |
| struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *) msg->l2h; |
| struct gprs_nsvc *nsvc; |
| int rc = 0; |
| |
| /* look up the NSVC based on source address */ |
| nsvc = nsvc_by_rem_addr(nsi, saddr); |
| if (!nsvc) { |
| struct tlv_parsed tp; |
| uint16_t nsei; |
| if (nsh->pdu_type == NS_PDUT_STATUS) { |
| LOGP(DNS, LOGL_INFO, "Ignoring NS STATUS from %s:%u " |
| "for non-existing NS-VC\n", |
| inet_ntoa(saddr->sin_addr), ntohs(saddr->sin_port)); |
| return 0; |
| } |
| /* Only the RESET procedure creates a new NSVC */ |
| if (nsh->pdu_type != NS_PDUT_RESET) { |
| /* Since we have no NSVC, we have to use a fake */ |
| nsvc = nsi->unknown_nsvc; |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| LOGP(DNS, LOGL_INFO, "Rejecting NS PDU type 0x%0x " |
| "from %s:%u for non-existing NS-VC\n", |
| nsh->pdu_type, inet_ntoa(saddr->sin_addr), |
| ntohs(saddr->sin_port)); |
| nsvc->nsvci = nsvc->nsei = 0xfffe; |
| nsvc->ip.bts_addr = *saddr; |
| nsvc->state = NSE_S_ALIVE; |
| nsvc->ll = ll; |
| #if 0 |
| return gprs_ns_tx_reset(nsvc, NS_CAUSE_PDU_INCOMP_PSTATE); |
| #else |
| return gprs_ns_tx_status(nsvc, |
| NS_CAUSE_PDU_INCOMP_PSTATE, 0, |
| msg); |
| #endif |
| } |
| rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data, |
| msgb_l2len(msg) - sizeof(*nsh), 0, 0); |
| if (rc < 0) { |
| LOGP(DNS, LOGL_ERROR, "Rx NS RESET Error %d during " |
| "TLV Parse\n", rc); |
| return rc; |
| } |
| if (!TLVP_PRESENT(&tp, NS_IE_CAUSE) || |
| !TLVP_PRESENT(&tp, NS_IE_VCI) || |
| !TLVP_PRESENT(&tp, NS_IE_NSEI)) { |
| LOGP(DNS, LOGL_ERROR, "NS RESET Missing mandatory IE\n"); |
| gprs_ns_tx_status(nsvc, NS_CAUSE_MISSING_ESSENT_IE, 0, |
| msg); |
| return -EINVAL; |
| } |
| nsei = ntohs(*(uint16_t *)TLVP_VAL(&tp, NS_IE_NSEI)); |
| /* Check if we already know this NSEI, the remote end might |
| * simply have changed addresses, or it is a SGSN */ |
| nsvc = nsvc_by_nsei(nsi, nsei); |
| if (!nsvc) { |
| nsvc = nsvc_create(nsi, 0xffff); |
| nsvc->ll = ll; |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| LOGP(DNS, LOGL_INFO, "Creating NS-VC for BSS at %s:%u\n", |
| inet_ntoa(saddr->sin_addr), ntohs(saddr->sin_port)); |
| } |
| /* Update the remote peer IP address/port */ |
| nsvc->ip.bts_addr = *saddr; |
| } else |
| msgb_nsei(msg) = nsvc->nsei; |
| |
| log_set_context(BSC_CTX_NSVC, nsvc); |
| |
| /* Increment number of Incoming bytes */ |
| rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_PKTS_IN]); |
| rate_ctr_add(&nsvc->ctrg->ctr[NS_CTR_BYTES_IN], msgb_l2len(msg)); |
| |
| switch (nsh->pdu_type) { |
| case NS_PDUT_ALIVE: |
| /* If we're dead and blocked and suddenly receive a |
| * NS-ALIVE out of the blue, we might have been re-started |
| * and should send a NS-RESET to make sure everything recovers |
| * fine. */ |
| if (nsvc->state == NSE_S_BLOCKED) |
| rc = gprs_ns_tx_reset(nsvc, NS_CAUSE_PDU_INCOMP_PSTATE); |
| else |
| rc = gprs_ns_tx_alive_ack(nsvc); |
| break; |
| case NS_PDUT_ALIVE_ACK: |
| /* stop Tns-alive and start Tns-test */ |
| nsvc_start_timer(nsvc, NSVC_TIMER_TNS_TEST); |
| if (nsvc->remote_end_is_sgsn) { |
| /* FIXME: this should be one level higher */ |
| if (nsvc->state & NSE_S_BLOCKED) |
| rc = gprs_ns_tx_unblock(nsvc); |
| } |
| break; |
| case NS_PDUT_UNITDATA: |
| /* actual user data */ |
| rc = gprs_ns_rx_unitdata(nsvc, msg); |
| break; |
| case NS_PDUT_STATUS: |
| rc = gprs_ns_rx_status(nsvc, msg); |
| break; |
| case NS_PDUT_RESET: |
| rc = gprs_ns_rx_reset(nsvc, msg); |
| break; |
| case NS_PDUT_RESET_ACK: |
| LOGP(DNS, LOGL_INFO, "NSEI=%u Rx NS RESET ACK\n", nsvc->nsei); |
| /* mark NS-VC as blocked + active */ |
| nsvc->state = NSE_S_BLOCKED | NSE_S_ALIVE; |
| nsvc->remote_state = NSE_S_BLOCKED | NSE_S_ALIVE; |
| rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_BLOCKED]); |
| if (nsvc->persistent || nsvc->remote_end_is_sgsn) { |
| /* stop RESET timer */ |
| bsc_del_timer(&nsvc->timer); |
| } |
| /* Initiate TEST proc.: Send ALIVE and start timer */ |
| rc = gprs_ns_tx_simple(nsvc, NS_PDUT_ALIVE); |
| nsvc_start_timer(nsvc, NSVC_TIMER_TNS_TEST); |
| break; |
| case NS_PDUT_UNBLOCK: |
| /* Section 7.2: unblocking procedure */ |
| LOGP(DNS, LOGL_INFO, "NSEI=%u Rx NS UNBLOCK\n", nsvc->nsei); |
| nsvc->state &= ~NSE_S_BLOCKED; |
| ns_dispatch_signal(nsvc, S_NS_UNBLOCK, 0); |
| rc = gprs_ns_tx_simple(nsvc, NS_PDUT_UNBLOCK_ACK); |
| break; |
| case NS_PDUT_UNBLOCK_ACK: |
| LOGP(DNS, LOGL_INFO, "NSEI=%u Rx NS UNBLOCK ACK\n", nsvc->nsei); |
| /* mark NS-VC as unblocked + active */ |
| nsvc->state = NSE_S_ALIVE; |
| nsvc->remote_state = NSE_S_ALIVE; |
| ns_dispatch_signal(nsvc, S_NS_UNBLOCK, 0); |
| break; |
| case NS_PDUT_BLOCK: |
| rc = gprs_ns_rx_block(nsvc, msg); |
| break; |
| case NS_PDUT_BLOCK_ACK: |
| LOGP(DNS, LOGL_INFO, "NSEI=%u Rx NS BLOCK ACK\n", nsvc->nsei); |
| /* mark remote NS-VC as blocked + active */ |
| nsvc->remote_state = NSE_S_BLOCKED | NSE_S_ALIVE; |
| break; |
| default: |
| LOGP(DNS, LOGL_NOTICE, "NSEI=%u Rx Unknown NS PDU type 0x%02x\n", |
| nsvc->nsei, nsh->pdu_type); |
| rc = -EINVAL; |
| break; |
| } |
| return rc; |
| } |
| |
| struct gprs_ns_inst *gprs_ns_instantiate(gprs_ns_cb_t *cb) |
| { |
| struct gprs_ns_inst *nsi = talloc_zero(tall_bsc_ctx, struct gprs_ns_inst); |
| |
| nsi->cb = cb; |
| INIT_LLIST_HEAD(&nsi->gprs_nsvcs); |
| nsi->timeout[NS_TOUT_TNS_BLOCK] = 3; |
| nsi->timeout[NS_TOUT_TNS_BLOCK_RETRIES] = 3; |
| nsi->timeout[NS_TOUT_TNS_RESET] = 3; |
| nsi->timeout[NS_TOUT_TNS_RESET_RETRIES] = 3; |
| nsi->timeout[NS_TOUT_TNS_TEST] = 30; |
| nsi->timeout[NS_TOUT_TNS_ALIVE] = 3; |
| nsi->timeout[NS_TOUT_TNS_ALIVE_RETRIES] = 10; |
| |
| /* Create the dummy NSVC that we use for sending |
| * messages to non-existant/unknown NS-VC's */ |
| nsi->unknown_nsvc = nsvc_create(nsi, 0xfffe); |
| llist_del(&nsi->unknown_nsvc->list); |
| |
| return nsi; |
| } |
| |
| void gprs_ns_destroy(struct gprs_ns_inst *nsi) |
| { |
| /* FIXME: clear all timers */ |
| |
| /* recursively free the NSI and all its NSVCs */ |
| talloc_free(nsi); |
| } |
| |
| |
| /* NS-over-IP code, according to 3GPP TS 48.016 Chapter 6.2 |
| * We don't support Size Procedure, Configuration Procedure, ChangeWeight Procedure */ |
| |
| /* Read a single NS-over-IP message */ |
| static struct msgb *read_nsip_msg(struct bsc_fd *bfd, int *error, |
| struct sockaddr_in *saddr) |
| { |
| struct msgb *msg = gprs_ns_msgb_alloc(); |
| int ret = 0; |
| socklen_t saddr_len = sizeof(*saddr); |
| |
| if (!msg) { |
| *error = -ENOMEM; |
| return NULL; |
| } |
| |
| ret = recvfrom(bfd->fd, msg->data, NS_ALLOC_SIZE - NS_ALLOC_HEADROOM, 0, |
| (struct sockaddr *)saddr, &saddr_len); |
| if (ret < 0) { |
| LOGP(DNS, LOGL_ERROR, "recv error %s during NSIP recv\n", |
| strerror(errno)); |
| msgb_free(msg); |
| *error = ret; |
| return NULL; |
| } else if (ret == 0) { |
| msgb_free(msg); |
| *error = ret; |
| return NULL; |
| } |
| |
| msg->l2h = msg->data; |
| msgb_put(msg, ret); |
| |
| return msg; |
| } |
| |
| static int handle_nsip_read(struct bsc_fd *bfd) |
| { |
| int error; |
| struct sockaddr_in saddr; |
| struct gprs_ns_inst *nsi = bfd->data; |
| struct msgb *msg = read_nsip_msg(bfd, &error, &saddr); |
| |
| if (!msg) |
| return error; |
| |
| error = gprs_ns_rcvmsg(nsi, msg, &saddr, GPRS_NS_LL_UDP); |
| |
| msgb_free(msg); |
| |
| return error; |
| } |
| |
| static int handle_nsip_write(struct bsc_fd *bfd) |
| { |
| /* FIXME: actually send the data here instead of nsip_sendmsg() */ |
| return -EIO; |
| } |
| |
| static int nsip_sendmsg(struct gprs_nsvc *nsvc, struct msgb *msg) |
| { |
| int rc; |
| struct gprs_ns_inst *nsi = nsvc->nsi; |
| struct sockaddr_in *daddr = &nsvc->ip.bts_addr; |
| |
| rc = sendto(nsi->nsip.fd.fd, msg->data, msg->len, 0, |
| (struct sockaddr *)daddr, sizeof(*daddr)); |
| |
| talloc_free(msg); |
| |
| return rc; |
| } |
| |
| /* UDP Port 23000 carries the LLC-in-BSSGP-in-NS protocol stack */ |
| static int nsip_fd_cb(struct bsc_fd *bfd, unsigned int what) |
| { |
| int rc = 0; |
| |
| if (what & BSC_FD_READ) |
| rc = handle_nsip_read(bfd); |
| if (what & BSC_FD_WRITE) |
| rc = handle_nsip_write(bfd); |
| |
| return rc; |
| } |
| |
| /* Listen for incoming GPRS packets */ |
| int gprs_ns_nsip_listen(struct gprs_ns_inst *nsi) |
| { |
| int ret; |
| |
| ret = make_sock(&nsi->nsip.fd, IPPROTO_UDP, nsi->nsip.local_ip, |
| nsi->nsip.local_port, nsip_fd_cb); |
| if (ret < 0) |
| return ret; |
| |
| nsi->nsip.fd.data = nsi; |
| |
| return ret; |
| } |
| |
| /* Initiate a RESET procedure */ |
| void gprs_nsvc_reset(struct gprs_nsvc *nsvc, uint8_t cause) |
| { |
| LOGP(DNS, LOGL_INFO, "NSEI=%u RESET procedure based on API request\n", |
| nsvc->nsei); |
| |
| /* Mark NS-VC locally as blocked and dead */ |
| nsvc->state = NSE_S_BLOCKED; |
| /* Send NS-RESET PDU */ |
| if (gprs_ns_tx_reset(nsvc, cause) < 0) { |
| LOGP(DNS, LOGL_ERROR, "NSEI=%u, error resetting NS-VC\n", |
| nsvc->nsei); |
| } |
| /* Start Tns-reset */ |
| nsvc_start_timer(nsvc, NSVC_TIMER_TNS_RESET); |
| } |
| |
| /* Establish a connection (from the BSS) to the SGSN */ |
| struct gprs_nsvc *nsip_connect(struct gprs_ns_inst *nsi, |
| struct sockaddr_in *dest, uint16_t nsei, |
| uint16_t nsvci) |
| { |
| struct gprs_nsvc *nsvc; |
| |
| nsvc = nsvc_by_rem_addr(nsi, dest); |
| if (!nsvc) |
| nsvc = nsvc_create(nsi, nsvci); |
| nsvc->ip.bts_addr = *dest; |
| nsvc->nsei = nsei; |
| nsvc->nsvci = nsvci; |
| nsvc->remote_end_is_sgsn = 1; |
| |
| gprs_nsvc_reset(nsvc, NS_CAUSE_OM_INTERVENTION); |
| return nsvc; |
| } |