mirror of https://gerrit.osmocom.org/libosmocore
636 lines
17 KiB
C
636 lines
17 KiB
C
/* GPRS Networks Service (NS) messages on the Gb interfacebvci = msgb_bvci(msg);
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* 3GPP TS 08.16 version 8.0.1 Release 1999 / ETSI TS 101 299 V8.0.1 (2002-05) */
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/* (C) 2009-2010 by Harald Welte <laforge@gnumonks.org>
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*
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* All Rights Reserved
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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*/
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/* Some introduction into NS: NS is used typically on top of frame relay,
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* but in the ip.access world it is encapsulated in UDP packets. It serves
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* as an intermediate shim betwen BSSGP and the underlying medium. It doesn't
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* do much, apart from providing congestion notification and status indication.
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*
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* Terms:
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* NS Network Service
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* NSVC NS Virtual Connection
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* NSEI NS Entity Identifier
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* NSVL NS Virtual Link
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* NSVLI NS Virtual Link Identifier
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* BVC BSSGP Virtual Connection
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* BVCI BSSGP Virtual Connection Identifier
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* NSVCG NS Virtual Connection Goup
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* Blocked NS-VC cannot be used for user traffic
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* Alive Ability of a NS-VC to provide communication
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*
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* There can be multiple BSSGP virtual connections over one (group of) NSVC's. BSSGP will
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* therefore identify the BSSGP virtual connection by a BVCI passed down to NS.
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* NS then has to firgure out which NSVC's are responsible for this BVCI.
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* Those mappings are administratively configured.
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*/
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#include <stdlib.h>
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#include <unistd.h>
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#include <errno.h>
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#include <stdint.h>
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#include <arpa/inet.h>
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#include <openbsc/gsm_data.h>
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#include <osmocore/msgb.h>
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#include <osmocore/tlv.h>
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#include <osmocore/talloc.h>
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#include <osmocore/select.h>
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#include <openbsc/debug.h>
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#include <openbsc/gprs_ns.h>
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#include <openbsc/gprs_bssgp.h>
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#define NS_ALLOC_SIZE 1024
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static const struct tlv_definition ns_att_tlvdef = {
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.def = {
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[NS_IE_CAUSE] = { TLV_TYPE_TvLV, 0 },
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[NS_IE_VCI] = { TLV_TYPE_TvLV, 0 },
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[NS_IE_PDU] = { TLV_TYPE_TvLV, 0 },
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[NS_IE_BVCI] = { TLV_TYPE_TvLV, 0 },
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[NS_IE_NSEI] = { TLV_TYPE_TvLV, 0 },
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},
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};
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/* Lookup struct gprs_nsvc based on NSVCI */
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static struct gprs_nsvc *nsvc_by_nsvci(struct gprs_ns_inst *nsi,
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uint16_t nsvci)
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{
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struct gprs_nsvc *nsvc;
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llist_for_each_entry(nsvc, &nsi->gprs_nsvcs, list) {
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if (nsvc->nsvci == nsvci)
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return nsvc;
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}
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return NULL;
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}
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/* Lookup struct gprs_nsvc based on NSVCI */
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static struct gprs_nsvc *nsvc_by_nsei(struct gprs_ns_inst *nsi,
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uint16_t nsei)
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{
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struct gprs_nsvc *nsvc;
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llist_for_each_entry(nsvc, &nsi->gprs_nsvcs, list) {
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if (nsvc->nsei == nsei)
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return nsvc;
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}
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return NULL;
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}
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/* Lookup struct gprs_nsvc based on remote peer socket addr */
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static struct gprs_nsvc *nsvc_by_rem_addr(struct gprs_ns_inst *nsi,
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struct sockaddr_in *sin)
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{
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struct gprs_nsvc *nsvc;
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llist_for_each_entry(nsvc, &nsi->gprs_nsvcs, list) {
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if (!memcmp(&nsvc->ip.bts_addr, sin, sizeof(*sin)))
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return nsvc;
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}
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return NULL;
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}
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static void gprs_ns_timer_cb(void *data);
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static struct gprs_nsvc *nsvc_create(struct gprs_ns_inst *nsi, uint16_t nsvci)
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{
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struct gprs_nsvc *nsvc;
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nsvc = talloc_zero(nsi, struct gprs_nsvc);
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nsvc->nsvci = nsvci;
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/* before RESET procedure: BLOCKED and DEAD */
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nsvc->state = NSE_S_BLOCKED;
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nsvc->nsi = nsi;
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nsvc->timer.cb = gprs_ns_timer_cb;
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nsvc->timer.data = nsvc;
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llist_add(&nsvc->list, &nsi->gprs_nsvcs);
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return nsvc;
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}
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/* Section 10.3.2, Table 13 */
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static const struct value_string ns_cause_str[] = {
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{ NS_CAUSE_TRANSIT_FAIL, "Transit network failure" },
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{ NS_CAUSE_OM_INTERVENTION, "O&M intervention" },
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{ NS_CAUSE_EQUIP_FAIL, "Equipment failure" },
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{ NS_CAUSE_NSVC_BLOCKED, "NS-VC blocked" },
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{ NS_CAUSE_NSVC_UNKNOWN, "NS-VC unknown" },
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{ NS_CAUSE_BVCI_UNKNOWN, "BVCI unknown" },
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{ NS_CAUSE_SEM_INCORR_PDU, "Semantically incorrect PDU" },
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{ NS_CAUSE_PDU_INCOMP_PSTATE, "PDU not compatible with protocol state" },
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{ NS_CAUSE_PROTO_ERR_UNSPEC, "Protocol error, unspecified" },
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{ NS_CAUSE_INVAL_ESSENT_IE, "Invalid essential IE" },
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{ NS_CAUSE_MISSING_ESSENT_IE, "Missing essential IE" },
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{ 0, NULL }
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};
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const char *gprs_ns_cause_str(enum ns_cause cause)
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{
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return get_value_string(ns_cause_str, cause);
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}
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static int nsip_sendmsg(struct gprs_nsvc *nsvc, struct msgb *msg);
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static int gprs_ns_tx(struct gprs_nsvc *nsvc, struct msgb *msg)
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{
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int ret;
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switch (nsvc->nsi->ll) {
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case GPRS_NS_LL_UDP:
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ret = nsip_sendmsg(nsvc, msg);
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break;
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default:
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LOGP(DGPRS, LOGL_ERROR, "unsupported NS linklayer %u\n", nsvc->nsi->ll);
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msgb_free(msg);
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ret = -EIO;
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break;
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}
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return ret;
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}
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static int gprs_ns_tx_simple(struct gprs_nsvc *nsvc, uint8_t pdu_type)
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{
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struct msgb *msg = msgb_alloc(NS_ALLOC_SIZE, "GPRS/NS");
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struct gprs_ns_hdr *nsh;
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if (!msg)
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return -ENOMEM;
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nsh = (struct gprs_ns_hdr *) msgb_put(msg, sizeof(*nsh));
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nsh->pdu_type = pdu_type;
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return gprs_ns_tx(nsvc, msg);
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}
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static int gprs_ns_tx_reset(struct gprs_nsvc *nsvc, uint8_t cause)
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{
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struct msgb *msg = msgb_alloc(NS_ALLOC_SIZE, "GPRS/NS");
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struct gprs_ns_hdr *nsh;
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uint16_t nsvci = htons(nsvc->nsvci);
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uint16_t nsei = htons(nsvc->nsei);
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if (!msg)
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return -ENOMEM;
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nsh = (struct gprs_ns_hdr *) msgb_put(msg, sizeof(*nsh));
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nsh->pdu_type = NS_PDUT_RESET;
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msgb_tvlv_put(msg, NS_IE_CAUSE, 1, &cause);
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msgb_tvlv_put(msg, NS_IE_VCI, 2, (uint8_t *) &nsvci);
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msgb_tvlv_put(msg, NS_IE_NSEI, 2, (uint8_t *) &nsei);
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return gprs_ns_tx(nsvc, msg);
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}
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#define NS_ALIVE_RETRIES 10 /* after 3 failed retransmit we declare BTS as dead */
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static const uint8_t timer_mode_tout[_NSVC_TIMER_NR] = {
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[NSVC_TIMER_TNS_RESET] = 60,
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[NSVC_TIMER_TNS_ALIVE] = 3,
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[NSVC_TIMER_TNS_TEST] = 30,
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};
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static void nsvc_start_timer(struct gprs_nsvc *nsvc, enum nsvc_timer_mode mode)
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{
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nsvc->alive_retries = 0;
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if (bsc_timer_pending(&nsvc->timer))
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bsc_del_timer(&nsvc->timer);
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nsvc->timer_mode = mode;
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bsc_schedule_timer(&nsvc->timer, timer_mode_tout[mode], 0);
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}
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static void gprs_ns_timer_cb(void *data)
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{
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struct gprs_nsvc *nsvc = data;
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switch (nsvc->timer_mode) {
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case NSVC_TIMER_TNS_ALIVE:
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/* Tns-alive case: we expired without response ! */
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nsvc->alive_retries++;
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if (nsvc->alive_retries > NS_ALIVE_RETRIES) {
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/* mark as dead and blocked */
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nsvc->state = NSE_S_BLOCKED;
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DEBUGP(DGPRS, "NSEI=%u Tns-alive expired more then "
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"%u times, blocking NS-VC\n", nsvc->nsei,
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NS_ALIVE_RETRIES);
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/* FIXME: inform higher layers */
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return;
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}
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nsvc_start_timer(nsvc, NSVC_TIMER_TNS_ALIVE);
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break;
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case NSVC_TIMER_TNS_TEST:
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/* Tns-test case: send NS-ALIVE PDU */
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gprs_ns_tx_simple(nsvc, NS_PDUT_ALIVE);
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/* start Tns-alive timer */
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nsvc_start_timer(nsvc, NSVC_TIMER_TNS_ALIVE);
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break;
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case NSVC_TIMER_TNS_RESET:
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/* Chapter 7.3: Re-send the RESET */
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gprs_ns_tx_reset(nsvc, NS_CAUSE_OM_INTERVENTION);
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nsvc_start_timer(nsvc, NSVC_TIMER_TNS_RESET);
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break;
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}
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}
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/* Section 9.2.6 */
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static int gprs_ns_tx_reset_ack(struct gprs_nsvc *nsvc)
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{
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struct msgb *msg = msgb_alloc(NS_ALLOC_SIZE, "GPRS/NS");
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struct gprs_ns_hdr *nsh;
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uint16_t nsvci, nsei;
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if (!msg)
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return -ENOMEM;
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nsvci = htons(nsvc->nsvci);
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nsei = htons(nsvc->nsei);
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nsh = (struct gprs_ns_hdr *) msgb_put(msg, sizeof(*nsh));
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nsh->pdu_type = NS_PDUT_RESET_ACK;
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DEBUGP(DGPRS, "NSEI=%u Tx NS RESET ACK (NSVCI=%u)\n",
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nsvc->nsei, nsvc->nsvci);
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msgb_tvlv_put(msg, NS_IE_VCI, 2, (uint8_t *)&nsvci);
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msgb_tvlv_put(msg, NS_IE_NSEI, 2, (uint8_t *)&nsei);
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return gprs_ns_tx(nsvc, msg);
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}
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/* Section 9.2.10: transmit side / NS-UNITDATA-REQUEST primitive */
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int gprs_ns_sendmsg(struct gprs_ns_inst *nsi, struct msgb *msg)
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{
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struct gprs_nsvc *nsvc;
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struct gprs_ns_hdr *nsh;
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uint16_t bvci = msgb_bvci(msg);
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nsvc = nsvc_by_nsei(nsi, msgb_nsei(msg));
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if (!nsvc) {
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LOGP(DGPRS, LOGL_ERROR, "Unable to resolve NSEI %u "
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"to NS-VC!\n", msgb_nsei(msg));
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return -EINVAL;
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}
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if (!(nsvc->state & NSE_S_ALIVE)) {
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LOGP(DGPRS, LOGL_ERROR, "NSEI=%u is not alive, cannot send\n",
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nsvc->nsei);
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return -EBUSY;
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}
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if (nsvc->state & NSE_S_BLOCKED) {
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LOGP(DGPRS, LOGL_ERROR, "NSEI=%u is blocked, cannot send\n",
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nsvc->nsei);
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return -EBUSY;
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}
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nsh = (struct gprs_ns_hdr *) msgb_push(msg, sizeof(*nsh) + 3);
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if (!nsh) {
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LOGP(DGPRS, LOGL_ERROR, "Not enough headroom for NS header\n");
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return -EIO;
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}
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nsh->pdu_type = NS_PDUT_UNITDATA;
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/* spare octet in data[0] */
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nsh->data[1] = bvci >> 8;
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nsh->data[2] = bvci & 0xff;
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return gprs_ns_tx(nsvc, msg);
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}
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/* Section 9.2.10: receive side */
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static int gprs_ns_rx_unitdata(struct gprs_nsvc *nsvc, struct msgb *msg)
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{
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struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *)msg->l2h;
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uint16_t bvci;
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/* spare octet in data[0] */
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bvci = nsh->data[1] << 8 | nsh->data[2];
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msgb_bssgph(msg) = &nsh->data[3];
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msgb_bvci(msg) = bvci;
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/* call upper layer (BSSGP) */
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return nsvc->nsi->cb(GPRS_NS_EVT_UNIT_DATA, nsvc, msg, bvci);
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}
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/* Section 9.2.7 */
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static int gprs_ns_rx_status(struct gprs_nsvc *nsvc, struct msgb *msg)
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{
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struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *) msg->l2h;
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struct tlv_parsed tp;
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uint8_t cause;
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int rc;
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DEBUGP(DGPRS, "NSEI=%u NS STATUS ", nsvc->nsei);
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rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data, msgb_l2len(msg), 0, 0);
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if (!TLVP_PRESENT(&tp, NS_IE_CAUSE)) {
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DEBUGPC(DGPRS, "missing cause IE\n");
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return -EINVAL;
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}
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cause = *TLVP_VAL(&tp, NS_IE_CAUSE);
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DEBUGPC(DGPRS, "cause=%s\n", gprs_ns_cause_str(cause));
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return 0;
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}
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/* Section 7.3 */
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static int gprs_ns_rx_reset(struct gprs_nsvc *nsvc, struct msgb *msg)
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{
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struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *) msg->l2h;
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struct tlv_parsed tp;
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uint8_t *cause;
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uint16_t *nsvci, *nsei;
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int rc;
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rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data, msgb_l2len(msg), 0, 0);
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if (!TLVP_PRESENT(&tp, NS_IE_CAUSE) ||
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!TLVP_PRESENT(&tp, NS_IE_VCI) ||
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!TLVP_PRESENT(&tp, NS_IE_NSEI)) {
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/* FIXME: respond with NS_CAUSE_MISSING_ESSENT_IE */
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LOGP(DGPRS, LOGL_ERROR, "NS RESET Missing mandatory IE\n");
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return -EINVAL;
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}
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cause = (uint8_t *) TLVP_VAL(&tp, NS_IE_CAUSE);
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nsvci = (uint16_t *) TLVP_VAL(&tp, NS_IE_VCI);
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nsei = (uint16_t *) TLVP_VAL(&tp, NS_IE_NSEI);
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DEBUGP(DGPRS, "NSEI=%u NS RESET (NSVCI=%u, cause=%s)\n",
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nsvc->nsvci, nsvc->nsei, gprs_ns_cause_str(*cause));
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nsvc->state = NSE_S_BLOCKED | NSE_S_ALIVE;
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nsvc->nsei = ntohs(*nsei);
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nsvc->nsvci = ntohs(*nsvci);
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/* mark the NS-VC as blocked and alive */
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/* start the test procedure */
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nsvc_start_timer(nsvc, NSVC_TIMER_TNS_ALIVE);
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return gprs_ns_tx_reset_ack(nsvc);
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}
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/* main entry point, here incoming NS frames enter */
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int gprs_ns_rcvmsg(struct gprs_ns_inst *nsi, struct msgb *msg,
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struct sockaddr_in *saddr)
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{
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struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *) msg->l2h;
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struct gprs_nsvc *nsvc;
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int rc = 0;
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/* look up the NSVC based on source address */
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nsvc = nsvc_by_rem_addr(nsi, saddr);
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if (!nsvc) {
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/* Only the RESET procedure creates a new NSVC */
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if (nsh->pdu_type != NS_PDUT_RESET) {
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LOGP(DGPRS, LOGL_INFO, "Ignoring NS PDU type 0x%0x "
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"from %s for non-existing NS-VC\n",
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nsh->pdu_type, inet_ntoa(saddr->sin_addr));
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//gprs_ns_tx_reset(nsvc, NS_CAUSE_NSVC_UNKNOWN);
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return -EIO;
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}
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LOGP(DGPRS, LOGL_INFO, "Creating NS-VC for BSS at %s:%u\n",
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inet_ntoa(saddr->sin_addr), ntohs(saddr->sin_port));
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nsvc = nsvc_create(nsi, 0xffff);
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nsvc->ip.bts_addr = *saddr;
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} else
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msgb_nsei(msg) = nsvc->nsei;
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switch (nsh->pdu_type) {
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case NS_PDUT_ALIVE:
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/* remote end inquires whether we're still alive,
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* we need to respond with ALIVE_ACK */
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rc = gprs_ns_tx_simple(nsvc, NS_PDUT_ALIVE_ACK);
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break;
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case NS_PDUT_ALIVE_ACK:
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/* stop Tns-alive */
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bsc_del_timer(&nsvc->timer);
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/* start Tns-test */
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nsvc_start_timer(nsvc, NSVC_TIMER_TNS_TEST);
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break;
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case NS_PDUT_UNITDATA:
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/* actual user data */
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rc = gprs_ns_rx_unitdata(nsvc, msg);
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break;
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case NS_PDUT_STATUS:
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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:
|
|
DEBUGP(DGPRS, "NSEI=%u Rx NS RESET ACK\n", nsvc->nsei);
|
|
/* mark remote NS-VC as blocked + active */
|
|
nsvc->remote_state = NSE_S_BLOCKED | NSE_S_ALIVE;
|
|
if (nsvc->remote_end_is_sgsn) {
|
|
/* stop RESET timer */
|
|
bsc_del_timer(&nsvc->timer);
|
|
/* send ALIVE PDU */
|
|
rc = gprs_ns_tx_simple(nsvc, NS_PDUT_ALIVE);
|
|
nsvc_start_timer(nsvc, NSVC_TIMER_TNS_ALIVE);
|
|
}
|
|
break;
|
|
case NS_PDUT_UNBLOCK:
|
|
/* Section 7.2: unblocking procedure */
|
|
DEBUGP(DGPRS, "NSEI=%u Rx NS UNBLOCK\n", nsvc->nsei);
|
|
nsvc->state &= ~NSE_S_BLOCKED;
|
|
rc = gprs_ns_tx_simple(nsvc, NS_PDUT_UNBLOCK_ACK);
|
|
break;
|
|
case NS_PDUT_UNBLOCK_ACK:
|
|
DEBUGP(DGPRS, "NSEI=%u Rx NS UNBLOCK ACK\n", nsvc->nsei);
|
|
/* mark remote NS-VC as unblocked + active */
|
|
nsvc->remote_state = NSE_S_ALIVE;
|
|
break;
|
|
case NS_PDUT_BLOCK:
|
|
DEBUGP(DGPRS, "NSEI=%u Rx NS BLOCK\n", nsvc->nsei);
|
|
nsvc->state |= NSE_S_BLOCKED;
|
|
rc = gprs_ns_tx_simple(nsvc, NS_PDUT_UNBLOCK_ACK);
|
|
break;
|
|
case NS_PDUT_BLOCK_ACK:
|
|
DEBUGP(DGPRS, "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:
|
|
DEBUGP(DGPRS, "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);
|
|
|
|
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 = msgb_alloc(NS_ALLOC_SIZE, "Abis/IP/GPRS-NS");
|
|
int ret = 0;
|
|
socklen_t saddr_len = sizeof(*saddr);
|
|
|
|
if (!msg) {
|
|
*error = -ENOMEM;
|
|
return NULL;
|
|
}
|
|
|
|
ret = recvfrom(bfd->fd, msg->data, NS_ALLOC_SIZE, 0,
|
|
(struct sockaddr *)saddr, &saddr_len);
|
|
if (ret < 0) {
|
|
LOGP(DGPRS, 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;
|
|
|
|
return gprs_ns_rcvmsg(nsi, msg, &saddr);
|
|
}
|
|
|
|
static int handle_nsip_write(struct bsc_fd *bfd)
|
|
{
|
|
/* FIXME: actually send the data here instead of nsip_sendmsg() */
|
|
return -EIO;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
|
|
/* FIXME: this is currently in input/ipaccess.c */
|
|
extern int make_sock(struct bsc_fd *bfd, int proto, uint16_t port,
|
|
int (*cb)(struct bsc_fd *fd, unsigned int what));
|
|
|
|
/* Listen for incoming GPRS packets */
|
|
int nsip_listen(struct gprs_ns_inst *nsi, uint16_t udp_port)
|
|
{
|
|
int ret;
|
|
|
|
ret = make_sock(&nsi->nsip.fd, IPPROTO_UDP, udp_port, nsip_fd_cb);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
nsi->ll = GPRS_NS_LL_UDP;
|
|
nsi->nsip.fd.data = nsi;
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* 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;
|
|
|
|
/* Initiate a RESET procedure */
|
|
if (gprs_ns_tx_reset(nsvc, NS_CAUSE_OM_INTERVENTION) < 0) {
|
|
LOGP(DGPRS, LOGL_ERROR, "NSEI=%u, error resetting NS-VC\n",
|
|
nsei);
|
|
}
|
|
/* run a timer and re-transmit the reset request? */
|
|
nsvc_start_timer(nsvc, NSVC_TIMER_TNS_RESET);
|
|
|
|
return nsvc;
|
|
}
|