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|
/* 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.
*/
#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 <openbsc/debug.h>
#include <openbsc/signal.h>
#include <openbsc/gprs_ns.h>
#include <openbsc/gprs_bssgp.h>
#define NS_ALLOC_SIZE 1024
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 },
},
};
/* Lookup struct gprs_nsvc based on NSVCI */
static 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 */
static 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);
static struct gprs_nsvc *nsvc_create(struct gprs_ns_inst *nsi, uint16_t nsvci)
{
struct gprs_nsvc *nsvc;
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;
llist_add(&nsvc->list, &nsi->gprs_nsvcs);
return nsvc;
}
static 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);
static int gprs_ns_tx(struct gprs_nsvc *nsvc, struct msgb *msg)
{
int ret;
switch (nsvc->nsi->ll) {
case GPRS_NS_LL_UDP:
ret = nsip_sendmsg(nsvc, msg);
break;
default:
LOGP(DNS, LOGL_ERROR, "unsupported NS linklayer %u\n", nsvc->nsi->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 = msgb_alloc(NS_ALLOC_SIZE, "GPRS/NS");
struct gprs_ns_hdr *nsh;
if (!msg)
return -ENOMEM;
nsh = (struct gprs_ns_hdr *) msgb_put(msg, sizeof(*nsh));
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 = msgb_alloc(NS_ALLOC_SIZE, "GPRS/NS");
struct gprs_ns_hdr *nsh;
uint16_t nsvci = htons(nsvc->nsvci);
uint16_t nsei = htons(nsvc->nsei);
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));
nsh = (struct gprs_ns_hdr *) msgb_put(msg, sizeof(*nsh));
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 = msgb_alloc(NS_ALLOC_SIZE, "GPRS/NS");
struct gprs_ns_hdr *nsh;
uint16_t nsvci = htons(nsvc->nsvci);
bvci = htons(bvci);
if (!msg)
return -ENOMEM;
LOGP(DNS, LOGL_INFO, "NSEI=%u Tx NS STATUS (NSVCI=%u, cause=%s)\n",
nsvc->nsei, nsvc->nsvci, gprs_ns_cause_str(cause));
nsh = (struct gprs_ns_hdr *) msgb_put(msg, sizeof(*nsh));
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 = msgb_alloc(NS_ALLOC_SIZE, "GPRS/NS");
struct gprs_ns_hdr *nsh;
uint16_t nsvci = htons(nsvc->nsvci);
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;
nsh = (struct gprs_ns_hdr *) msgb_put(msg, sizeof(*nsh));
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)
{
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)
{
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)
{
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);
}
#define NS_ALIVE_RETRIES 10 /* after 3 failed retransmit we declare BTS as dead */
static const uint8_t timer_mode_tout[_NSVC_TIMER_NR] = {
[NSVC_TIMER_TNS_RESET] = 60,
[NSVC_TIMER_TNS_ALIVE] = 3,
[NSVC_TIMER_TNS_TEST] = 30,
};
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)
{
DEBUGP(DNS, "NSEI=%u Starting timer in mode %s (%u seconds)\n",
nsvc->nsei, get_value_string(timer_mode_strs, mode),
timer_mode_tout[mode]);
if (bsc_timer_pending(&nsvc->timer))
bsc_del_timer(&nsvc->timer);
nsvc->timer_mode = mode;
bsc_schedule_timer(&nsvc->timer, timer_mode_tout[mode], 0);
}
static void gprs_ns_timer_cb(void *data)
{
struct gprs_nsvc *nsvc = data;
DEBUGP(DNS, "NSEI=%u Timer expired in mode %s (%u seconds)\n",
nsvc->nsei, get_value_string(timer_mode_strs, nsvc->timer_mode),
timer_mode_tout[nsvc->timer_mode]);
switch (nsvc->timer_mode) {
case NSVC_TIMER_TNS_ALIVE:
/* Tns-alive case: we expired without response ! */
nsvc->alive_retries++;
if (nsvc->alive_retries > NS_ALIVE_RETRIES) {
/* mark as dead and blocked */
nsvc->state = NSE_S_BLOCKED;
LOGP(DNS, LOGL_NOTICE,
"NSEI=%u Tns-alive expired more then "
"%u times, blocking NS-VC\n", nsvc->nsei,
NS_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 = msgb_alloc(NS_ALLOC_SIZE, "GPRS/NS");
struct gprs_ns_hdr *nsh;
uint16_t nsvci, nsei;
if (!msg)
return -ENOMEM;
nsvci = htons(nsvc->nsvci);
nsei = htons(nsvc->nsei);
nsh = (struct gprs_ns_hdr *) msgb_put(msg, sizeof(*nsh));
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;
}
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;
}
nsh = (struct gprs_ns_hdr *) msgb_push(msg, sizeof(*nsh) + 3);
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_INFO, "NSEI=%u NS STATUS ", nsvc->nsei);
rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data, msgb_l2len(msg), 0, 0);
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_INFO, "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), 0, 0);
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 */
nsvc_start_timer(nsvc, NSVC_TIMER_TNS_ALIVE);
/* 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), 0, 0);
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);
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)
{
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;
/* Only the RESET procedure creates a new NSVC */
if (nsh->pdu_type != NS_PDUT_RESET) {
struct gprs_nsvc fake_nsvc;
LOGP(DNS, LOGL_INFO, "Ignoring 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));
/* Since we have no NSVC, we have to create a fake */
fake_nsvc.nsvci = fake_nsvc.nsei = 0;
fake_nsvc.nsi = nsi;
fake_nsvc.ip.bts_addr = *saddr;
fake_nsvc.state = NSE_S_ALIVE;
return gprs_ns_tx_status(&fake_nsvc,
NS_CAUSE_PDU_INCOMP_PSTATE, 0,
msg);
}
rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data,
msgb_l2len(msg), 0, 0);
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) {
LOGP(DNS, LOGL_INFO, "Creating NS-VC for BSS at %s:%u\n",
inet_ntoa(saddr->sin_addr), ntohs(saddr->sin_port));
nsvc = nsvc_create(nsi, 0xffff);
}
/* Update the remote peer IP address/port */
nsvc->ip.bts_addr = *saddr;
} else
msgb_nsei(msg) = nsvc->nsei;
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 */
bsc_del_timer(&nsvc->timer);
/* 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;
if (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_ALIVE);
}
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);
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(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;
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;
}
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 */
/* Mark NS-VC locally as blocked and dead */
nsvc->state = NSE_S_BLOCKED;
/* Send NS-RESET PDU */
if (gprs_ns_tx_reset(nsvc, NS_CAUSE_OM_INTERVENTION) < 0) {
LOGP(DNS, LOGL_ERROR, "NSEI=%u, error resetting NS-VC\n",
nsei);
}
/* Start Tns-reset */
nsvc_start_timer(nsvc, NSVC_TIMER_TNS_RESET);
return nsvc;
}
#include <vty/vty.h>
#include <vty/command.h>
static struct gprs_ns_inst *vty_nsi = NULL;
static struct cmd_node ns_node = {
NS_NODE,
"%s(ns)#",
1,
};
static int config_write_ns(struct vty *vty)
{
struct gprs_nsvc *nsvc;
vty_out(vty, "ns%s", VTY_NEWLINE);
llist_for_each_entry(nsvc, &vty_nsi->gprs_nsvcs, list) {
if (!nsvc->persistent)
continue;
vty_out(vty, " nse %u nsvci %u%s",
nsvc->nsei, nsvc->nsvci, VTY_NEWLINE);
vty_out(vty, " nse %u remote-role %s%s",
nsvc->nsei, nsvc->remote_end_is_sgsn ? "sgsn" : "bss",
VTY_NEWLINE);
if (nsvc->nsi->ll == GPRS_NS_LL_UDP) {
vty_out(vty, " nse %u remote-ip %s%s",
nsvc->nsei,
inet_ntoa(nsvc->ip.bts_addr.sin_addr),
VTY_NEWLINE);
vty_out(vty, " nse %u remote-port %u%s",
nsvc->nsei, ntohs(nsvc->ip.bts_addr.sin_port),
VTY_NEWLINE);
}
vty_out(vty, "%s", VTY_NEWLINE);
}
return CMD_SUCCESS;
}
DEFUN(cfg_ns, cfg_ns_cmd,
"ns",
"Configure the GPRS Network Service")
{
vty->node = NS_NODE;
return CMD_SUCCESS;
}
DEFUN(show_ns, show_ns_cmd, "show ns",
SHOW_STR "Display information about the NS protocol")
{
struct gprs_ns_inst *nsi = vty_nsi;
struct gprs_nsvc *nsvc;
llist_for_each_entry(nsvc, &nsi->gprs_nsvcs, list) {
vty_out(vty, "NSEI %5u, NS-VC %5u, Remote: %-4s, %5s %9s",
nsvc->nsei, nsvc->nsvci,
nsvc->remote_end_is_sgsn ? "SGSN" : "BSS",
nsvc->state & NSE_S_ALIVE ? "ALIVE" : "DEAD",
nsvc->state & NSE_S_BLOCKED ? "BLOCKED" : "UNBLOCKED");
if (nsvc->nsi->ll == GPRS_NS_LL_UDP)
vty_out(vty, ", %15s:%u",
inet_ntoa(nsvc->ip.bts_addr.sin_addr),
ntohs(nsvc->ip.bts_addr.sin_port));
vty_out(vty, "%s", VTY_NEWLINE);
}
return CMD_SUCCESS;
}
#define NSE_CMD_STR "NS Entity\n" "NS Entity ID (NSEI)\n"
DEFUN(cfg_nse_nsvc, cfg_nse_nsvci_cmd,
"nse <0-65535> nsvci <0-65534>",
NSE_CMD_STR
"NS Virtual Connection\n"
"NS Virtual Connection ID (NSVCI)\n"
)
{
uint16_t nsei = atoi(argv[0]);
uint16_t nsvci = atoi(argv[1]);
struct gprs_nsvc *
|