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-rw-r--r--src/gprs/gb_proxy.c684
1 files changed, 684 insertions, 0 deletions
diff --git a/src/gprs/gb_proxy.c b/src/gprs/gb_proxy.c
new file mode 100644
index 00000000..8df93a9c
--- /dev/null
+++ b/src/gprs/gb_proxy.c
@@ -0,0 +1,684 @@
+/* NS-over-IP proxy */
+
+/* (C) 2010 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2010 by On-Waves
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <getopt.h>
+#include <errno.h>
+#include <sys/fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <arpa/inet.h>
+
+#include <osmocore/talloc.h>
+#include <osmocore/select.h>
+
+#include <openbsc/signal.h>
+#include <openbsc/debug.h>
+#include <openbsc/gprs_ns.h>
+#include <openbsc/gprs_bssgp.h>
+#include <openbsc/gb_proxy.h>
+
+struct gbprox_peer {
+ struct llist_head list;
+
+ /* NS-VC over which we send/receive data to this BVC */
+ struct gprs_nsvc *nsvc;
+
+ /* BVCI used for Point-to-Point to this peer */
+ uint16_t bvci;
+ int blocked;
+
+ /* Routeing Area that this peer is part of (raw 04.08 encoding) */
+ uint8_t ra[6];
+};
+
+/* Linked list of all Gb peers (except SGSN) */
+static LLIST_HEAD(gbprox_bts_peers);
+
+/* Find the gbprox_peer by its BVCI */
+static struct gbprox_peer *peer_by_bvci(uint16_t bvci)
+{
+ struct gbprox_peer *peer;
+ llist_for_each_entry(peer, &gbprox_bts_peers, list) {
+ if (peer->bvci == bvci)
+ return peer;
+ }
+ return NULL;
+}
+
+static struct gbprox_peer *peer_by_nsvc(struct gprs_nsvc *nsvc)
+{
+ struct gbprox_peer *peer;
+ llist_for_each_entry(peer, &gbprox_bts_peers, list) {
+ if (peer->nsvc == nsvc)
+ return peer;
+ }
+ return NULL;
+}
+
+/* look-up a peer by its Routeing Area Code (RAC) */
+static struct gbprox_peer *peer_by_rac(const uint8_t *ra)
+{
+ struct gbprox_peer *peer;
+ llist_for_each_entry(peer, &gbprox_bts_peers, list) {
+ if (!memcmp(peer->ra, ra, 6))
+ return peer;
+ }
+ return NULL;
+}
+
+/* look-up a peer by its Location Area Code (LAC) */
+static struct gbprox_peer *peer_by_lac(const uint8_t *la)
+{
+ struct gbprox_peer *peer;
+ llist_for_each_entry(peer, &gbprox_bts_peers, list) {
+ if (!memcmp(peer->ra, la, 5))
+ return peer;
+ }
+ return NULL;
+}
+
+static struct gbprox_peer *peer_alloc(uint16_t bvci)
+{
+ struct gbprox_peer *peer;
+
+ peer = talloc_zero(tall_bsc_ctx, struct gbprox_peer);
+ if (!peer)
+ return NULL;
+
+ peer->bvci = bvci;
+ llist_add(&peer->list, &gbprox_bts_peers);
+
+ return peer;
+}
+
+static void peer_free(struct gbprox_peer *peer)
+{
+ llist_del(&peer->list);
+ talloc_free(peer);
+}
+
+/* FIXME: this needs to go to libosmocore/msgb.c */
+static struct msgb *msgb_copy(const struct msgb *msg, const char *name)
+{
+ struct openbsc_msgb_cb *old_cb, *new_cb;
+ struct msgb *new_msg;
+
+ new_msg = msgb_alloc(msg->data_len, name);
+ if (!new_msg)
+ return NULL;
+
+ /* copy data */
+ memcpy(new_msg->_data, msg->_data, new_msg->data_len);
+
+ /* copy header */
+ new_msg->len = msg->len;
+ new_msg->data += msg->data - msg->_data;
+ new_msg->head += msg->head - msg->_data;
+ new_msg->tail += msg->tail - msg->_data;
+
+ new_msg->l1h = new_msg->_data + (msg->l1h - msg->_data);
+ new_msg->l2h = new_msg->_data + (msg->l2h - msg->_data);
+ new_msg->l3h = new_msg->_data + (msg->l3h - msg->_data);
+ new_msg->l4h = new_msg->_data + (msg->l4h - msg->_data);
+
+ /* copy GB specific data */
+ old_cb = OBSC_MSGB_CB(msg);
+ new_cb = OBSC_MSGB_CB(new_msg);
+
+ new_cb->bssgph = new_msg->_data + (old_cb->bssgph - msg->_data);
+ new_cb->llch = new_msg->_data + (old_cb->llch - msg->_data);
+
+ /* bssgp_cell_id is a pointer into the old msgb, so we need to make
+ * it a pointer into the new msgb */
+ new_cb->bssgp_cell_id = new_msg->_data + (old_cb->bssgp_cell_id - msg->_data);
+ new_cb->nsei = old_cb->nsei;
+ new_cb->bvci = old_cb->bvci;
+ new_cb->tlli = old_cb->tlli;
+
+ return new_msg;
+}
+
+/* strip off the NS header */
+static void strip_ns_hdr(struct msgb *msg)
+{
+ int strip_len = msgb_bssgph(msg) - msg->data;
+ msgb_pull(msg, strip_len);
+}
+
+/* feed a message down the NS-VC associated with the specified peer */
+static int gbprox_relay2sgsn(struct msgb *old_msg, uint16_t ns_bvci)
+{
+ /* create a copy of the message so the old one can
+ * be free()d safely when we return from gbprox_rcvmsg() */
+ struct msgb *msg = msgb_copy(old_msg, "msgb_relay2sgsn");
+
+ DEBUGP(DGPRS, "NSEI=%u proxying BTS->SGSN (NS_BVCI=%u, NSEI=%u)\n",
+ msgb_nsei(msg), ns_bvci, gbcfg.nsip_sgsn_nsei);
+
+ msgb_bvci(msg) = ns_bvci;
+ msgb_nsei(msg) = gbcfg.nsip_sgsn_nsei;
+
+ strip_ns_hdr(msg);
+
+ return gprs_ns_sendmsg(bssgp_nsi, msg);
+}
+
+/* feed a message down the NS-VC associated with the specified peer */
+static int gbprox_relay2peer(struct msgb *old_msg, struct gbprox_peer *peer,
+ uint16_t ns_bvci)
+{
+ /* create a copy of the message so the old one can
+ * be free()d safely when we return from gbprox_rcvmsg() */
+ struct msgb *msg = msgb_copy(old_msg, "msgb_relay2peer");
+
+ DEBUGP(DGPRS, "NSEI=%u proxying SGSN->BSS (NS_BVCI=%u, NSEI=%u)\n",
+ msgb_nsei(msg), ns_bvci, peer->nsvc->nsei);
+
+ msgb_bvci(msg) = ns_bvci;
+ msgb_nsei(msg) = peer->nsvc->nsei;
+
+ /* Strip the old NS header, it will be replaced with a new one */
+ strip_ns_hdr(msg);
+
+ return gprs_ns_sendmsg(bssgp_nsi, msg);
+}
+
+static int block_unblock_peer(uint16_t ptp_bvci, uint8_t pdu_type)
+{
+ struct gbprox_peer *peer;
+
+ peer = peer_by_bvci(ptp_bvci);
+ if (!peer) {
+ LOGP(DGPRS, LOGL_ERROR, "BVCI=%u: Cannot find BSS\n",
+ ptp_bvci);
+ return -ENOENT;
+ }
+
+ switch (pdu_type) {
+ case BSSGP_PDUT_BVC_BLOCK_ACK:
+ peer->blocked = 1;
+ break;
+ case BSSGP_PDUT_BVC_UNBLOCK_ACK:
+ peer->blocked = 0;
+ break;
+ default:
+ break;
+ }
+ return 0;
+}
+
+/* Send a message to a peer identified by ptp_bvci but using ns_bvci
+ * in the NS hdr */
+static int gbprox_relay2bvci(struct msgb *msg, uint16_t ptp_bvci,
+ uint16_t ns_bvci)
+{
+ struct gbprox_peer *peer;
+
+ peer = peer_by_bvci(ptp_bvci);
+ if (!peer) {
+ LOGP(DGPRS, LOGL_ERROR, "BVCI=%u: Cannot find BSS\n",
+ ptp_bvci);
+ return -ENOENT;
+ }
+
+ return gbprox_relay2peer(msg, peer, ns_bvci);
+}
+
+/* Receive an incoming signalling message from a BSS-side NS-VC */
+static int gbprox_rx_sig_from_bss(struct msgb *msg, struct gprs_nsvc *nsvc,
+ uint16_t ns_bvci)
+{
+ struct bssgp_normal_hdr *bgph = (struct bssgp_normal_hdr *) msgb_bssgph(msg);
+ struct tlv_parsed tp;
+ uint8_t pdu_type = bgph->pdu_type;
+ int data_len = msgb_bssgp_len(msg) - sizeof(*bgph);
+ struct gbprox_peer *from_peer;
+ struct gprs_ra_id raid;
+
+ if (ns_bvci != 0 && ns_bvci != 1) {
+ LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u BVCI=%u is not signalling\n",
+ nsvc->nsei, ns_bvci);
+ return -EINVAL;
+ }
+
+ /* we actually should never see those two for BVCI == 0, but double-check
+ * just to make sure */
+ if (pdu_type == BSSGP_PDUT_UL_UNITDATA ||
+ pdu_type == BSSGP_PDUT_DL_UNITDATA) {
+ LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u UNITDATA not allowed in "
+ "signalling\n", nsvc->nsei);
+ return -EINVAL;
+ }
+
+ bssgp_tlv_parse(&tp, bgph->data, data_len);
+
+ switch (pdu_type) {
+ case BSSGP_PDUT_SUSPEND:
+ case BSSGP_PDUT_RESUME:
+ /* We implement RAC snooping during SUSPEND/RESUME, since
+ * it establishes a relationsip between BVCI/peer and the
+ * routeing area code. The snooped information is then
+ * used for routing the {SUSPEND,RESUME}_[N]ACK back to
+ * the correct BSSGP */
+ if (!TLVP_PRESENT(&tp, BSSGP_IE_ROUTEING_AREA))
+ goto err_mand_ie;
+ from_peer = peer_by_nsvc(nsvc);
+ if (!from_peer)
+ goto err_no_peer;
+ memcpy(from_peer->ra, TLVP_VAL(&tp, BSSGP_IE_ROUTEING_AREA),
+ sizeof(from_peer->ra));
+ gsm48_parse_ra(&raid, from_peer->ra);
+ LOGP(DGPRS, LOGL_INFO, "NSEI=%u BSSGP SUSPEND/RESUME "
+ "RAC snooping: RAC %u-%u-%u-%u behind BVCI=%u, "
+ "NSVCI=%u\n",nsvc->nsei, raid.mcc, raid.mnc, raid.lac,
+ raid.rac , from_peer->bvci, nsvc->nsvci);
+ /* FIXME: This only supports one BSS per RA */
+ break;
+ case BSSGP_PDUT_BVC_RESET:
+ /* If we receive a BVC reset on the signalling endpoint, we
+ * don't want the SGSN to reset, as the signalling endpoint
+ * is common for all point-to-point BVCs (and thus all BTS) */
+ if (TLVP_PRESENT(&tp, BSSGP_IE_BVCI)) {
+ uint16_t bvci = ntohs(*(uint16_t *)TLVP_VAL(&tp, BSSGP_IE_BVCI));
+ LOGP(DGPRS, LOGL_INFO, "NSEI=%u Rx BVC RESET (BVCI=%u)\n",
+ nsvc->nsei, bvci);
+ if (bvci == 0) {
+ /* FIXME: only do this if SGSN is alive! */
+ LOGP(DGPRS, LOGL_INFO, "NSEI=%u Tx fake "
+ "BVC RESET ACK of BVCI=0\n", nsvc->nsei);
+ return bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_RESET_ACK,
+ nsvc->nsei, 0, ns_bvci);
+ }
+ from_peer = peer_by_bvci(bvci);
+ if (!from_peer) {
+ /* if a PTP-BVC is reset, and we don't know that
+ * PTP-BVCI yet, we should allocate a new peer */
+ LOGP(DGPRS, LOGL_INFO, "Allocationg new peer for "
+ "BVCI=%u via NSVCI=%u/NSEI=%u\n", bvci,
+ nsvc->nsvci, nsvc->nsei);
+ from_peer = peer_alloc(bvci);
+ from_peer->nsvc = nsvc;
+ }
+ if (TLVP_PRESENT(&tp, BSSGP_IE_CELL_ID)) {
+ struct gprs_ra_id raid;
+ /* We have a Cell Identifier present in this
+ * PDU, this means we can extend our local
+ * state information about this particular cell
+ * */
+ memcpy(from_peer->ra,
+ TLVP_VAL(&tp, BSSGP_IE_CELL_ID),
+ sizeof(from_peer->ra));
+ gsm48_parse_ra(&raid, from_peer->ra);
+ LOGP(DGPRS, LOGL_INFO, "NSEI=%u/BVCI=%u "
+ "Cell ID %u-%u-%u-%u\n", nsvc->nsei,
+ bvci, raid.mcc, raid.mnc, raid.lac,
+ raid.rac);
+ }
+ }
+ break;
+ }
+
+ /* Normally, we can simply pass on all signalling messages from BSS to
+ * SGSN */
+ return gbprox_relay2sgsn(msg, ns_bvci);
+err_no_peer:
+ LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(BSS) cannot find peer based on RAC\n",
+ nsvc->nsei);
+ return bssgp_tx_status(BSSGP_CAUSE_UNKNOWN_BVCI, NULL, msg);
+err_mand_ie:
+ LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(BSS) missing mandatory RA IE\n",
+ nsvc->nsei);
+ return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, msg);
+}
+
+/* Receive paging request from SGSN, we need to relay to proper BSS */
+static int gbprox_rx_paging(struct msgb *msg, struct tlv_parsed *tp,
+ struct gprs_nsvc *nsvc, uint16_t ns_bvci)
+{
+ struct gbprox_peer *peer = NULL;
+
+ LOGP(DGPRS, LOGL_INFO, "NSEI=%u(SGSN) BSSGP PAGING ",
+ nsvc->nsei);
+ if (TLVP_PRESENT(tp, BSSGP_IE_BVCI)) {
+ uint16_t bvci = ntohs(*(uint16_t *)TLVP_VAL(tp, BSSGP_IE_BVCI));
+ LOGPC(DGPRS, LOGL_INFO, "routing by BVCI to peer BVCI=%u\n",
+ bvci);
+ } else if (TLVP_PRESENT(tp, BSSGP_IE_ROUTEING_AREA)) {
+ peer = peer_by_rac(TLVP_VAL(tp, BSSGP_IE_ROUTEING_AREA));
+ LOGPC(DGPRS, LOGL_INFO, "routing by RAC to peer BVCI=%u\n",
+ peer ? peer->bvci : -1);
+ } else if (TLVP_PRESENT(tp, BSSGP_IE_LOCATION_AREA)) {
+ peer = peer_by_lac(TLVP_VAL(tp, BSSGP_IE_LOCATION_AREA));
+ LOGPC(DGPRS, LOGL_INFO, "routing by LAC to peer BVCI=%u\n",
+ peer ? peer->bvci : -1);
+ } else
+ LOGPC(DGPRS, LOGL_INFO, "\n");
+
+ if (!peer) {
+ LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(SGSN) BSSGP PAGING: "
+ "unable to route, missing IE\n", nsvc->nsei);
+ return -EINVAL;
+ }
+ return gbprox_relay2peer(msg, peer, ns_bvci);
+}
+
+/* Receive an incoming BVC-RESET message from the SGSN */
+static int rx_reset_from_sgsn(struct msgb *msg, struct tlv_parsed *tp,
+ struct gprs_nsvc *nsvc, uint16_t ns_bvci)
+{
+ struct gbprox_peer *peer;
+ uint16_t ptp_bvci;
+
+ if (!TLVP_PRESENT(tp, BSSGP_IE_BVCI)) {
+ return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE,
+ NULL, msg);
+ }
+ ptp_bvci = ntohs(*(uint16_t *)TLVP_VAL(tp, BSSGP_IE_BVCI));
+
+ if (ptp_bvci >= 2) {
+ /* A reset for a PTP BVC was received, forward it to its
+ * respective peer */
+ peer = peer_by_bvci(ptp_bvci);
+ if (!peer) {
+ LOGP(DGPRS, LOGL_ERROR, "NSEI=%u BVCI=%u: Cannot find BSS\n",
+ nsvc->nsei, ptp_bvci);
+ return bssgp_tx_status(BSSGP_CAUSE_UNKNOWN_BVCI,
+ NULL, msg);
+ }
+ return gbprox_relay2peer(msg, peer, ns_bvci);
+ }
+
+ /* A reset for the Signalling entity has been received
+ * from the SGSN. As the signalling BVCI is shared
+ * among all the BSS's that we multiplex, it needs to
+ * be relayed */
+ llist_for_each_entry(peer, &gbprox_bts_peers, list)
+ gbprox_relay2peer(msg, peer, ns_bvci);
+
+ return 0;
+}
+
+/* Receive an incoming signalling message from the SGSN-side NS-VC */
+static int gbprox_rx_sig_from_sgsn(struct msgb *msg, struct gprs_nsvc *nsvc,
+ uint16_t ns_bvci)
+{
+ struct bssgp_normal_hdr *bgph = (struct bssgp_normal_hdr *) msgb_bssgph(msg);
+ struct tlv_parsed tp;
+ uint8_t pdu_type = bgph->pdu_type;
+ int data_len = msgb_bssgp_len(msg) - sizeof(*bgph);
+ struct gbprox_peer *peer;
+ uint16_t bvci;
+ int rc = 0;
+
+ if (ns_bvci != 0 && ns_bvci != 1) {
+ LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u(SGSN) BVCI=%u is not "
+ "signalling\n", nsvc->nsei, ns_bvci);
+ /* FIXME: Send proper error message */
+ return -EINVAL;
+ }
+
+ /* we actually should never see those two for BVCI == 0, but double-check
+ * just to make sure */
+ if (pdu_type == BSSGP_PDUT_UL_UNITDATA ||
+ pdu_type == BSSGP_PDUT_DL_UNITDATA) {
+ LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u(SGSN) UNITDATA not allowed in "
+ "signalling\n", nsvc->nsei);
+ return bssgp_tx_status(BSSGP_CAUSE_PROTO_ERR_UNSPEC, NULL, msg);
+ }
+
+ rc = bssgp_tlv_parse(&tp, bgph->data, data_len);
+
+ switch (pdu_type) {
+ case BSSGP_PDUT_BVC_RESET:
+ rc = rx_reset_from_sgsn(msg, &tp, nsvc, ns_bvci);
+ break;
+ case BSSGP_PDUT_FLUSH_LL:
+ case BSSGP_PDUT_BVC_RESET_ACK:
+ /* simple case: BVCI IE is mandatory */
+ if (!TLVP_PRESENT(&tp, BSSGP_IE_BVCI))
+ goto err_mand_ie;
+ bvci = ntohs(*(uint16_t *)TLVP_VAL(&tp, BSSGP_IE_BVCI));
+ rc = gbprox_relay2bvci(msg, bvci, ns_bvci);
+ break;
+ case BSSGP_PDUT_PAGING_PS:
+ case BSSGP_PDUT_PAGING_CS:
+ /* process the paging request (LAC/RAC lookup) */
+ rc = gbprox_rx_paging(msg, &tp, nsvc, ns_bvci);
+ break;
+ case BSSGP_PDUT_STATUS:
+ /* Some exception has occurred */
+ LOGP(DGPRS, LOGL_NOTICE,
+ "NSEI=%u(SGSN) BSSGP STATUS ", nsvc->nsei);
+ if (!TLVP_PRESENT(&tp, BSSGP_IE_CAUSE)) {
+ LOGPC(DGPRS, LOGL_NOTICE, "\n");
+ goto err_mand_ie;
+ }
+ LOGPC(DGPRS, LOGL_NOTICE,
+ "cause=0x%02x(%s) ", *TLVP_VAL(&tp, BSSGP_IE_CAUSE),
+ bssgp_cause_str(*TLVP_VAL(&tp, BSSGP_IE_CAUSE)));
+ if (TLVP_PRESENT(&tp, BSSGP_IE_BVCI)) {
+ uint16_t *bvci = (uint16_t *)
+ TLVP_VAL(&tp, BSSGP_IE_BVCI);
+ LOGPC(DGPRS, LOGL_NOTICE,
+ "BVCI=%u\n", ntohs(*bvci));
+ } else
+ LOGPC(DGPRS, LOGL_NOTICE, "\n");
+ break;
+ /* those only exist in the SGSN -> BSS direction */
+ case BSSGP_PDUT_SUSPEND_ACK:
+ case BSSGP_PDUT_SUSPEND_NACK:
+ case BSSGP_PDUT_RESUME_ACK:
+ case BSSGP_PDUT_RESUME_NACK:
+ /* RAC IE is mandatory */
+ if (!TLVP_PRESENT(&tp, BSSGP_IE_ROUTEING_AREA))
+ goto err_mand_ie;
+ peer = peer_by_rac(TLVP_VAL(&tp, BSSGP_IE_ROUTEING_AREA));
+ if (!peer)
+ goto err_no_peer;
+ rc = gbprox_relay2peer(msg, peer, ns_bvci);
+ break;
+ case BSSGP_PDUT_BVC_BLOCK_ACK:
+ case BSSGP_PDUT_BVC_UNBLOCK_ACK:
+ if (!TLVP_PRESENT(&tp, BSSGP_IE_BVCI))
+ goto err_mand_ie;
+ bvci = ntohs(*(uint16_t *)TLVP_VAL(&tp, BSSGP_IE_BVCI));
+ if (bvci == 0) {
+ LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u(SGSN) BSSGP "
+ "%sBLOCK_ACK for signalling BVCI ?!?\n", nsvc->nsei,
+ pdu_type == BSSGP_PDUT_BVC_UNBLOCK_ACK ? "UN":"");
+ /* should we send STATUS ? */
+ } else {
+ /* Mark BVC as (un)blocked */
+ block_unblock_peer(bvci, pdu_type);
+ }
+ rc = gbprox_relay2bvci(msg, bvci, ns_bvci);
+ break;
+ case BSSGP_PDUT_SGSN_INVOKE_TRACE:
+ LOGP(DGPRS, LOGL_ERROR,
+ "NSEI=%u(SGSN) BSSGP INVOKE TRACE not supported\n",nsvc->nsei);
+ rc = bssgp_tx_status(BSSGP_CAUSE_PDU_INCOMP_FEAT, NULL, msg);
+ break;
+ default:
+ LOGP(DGPRS, LOGL_NOTICE, "BSSGP PDU type 0x%02x unknown\n",
+ pdu_type);
+ rc = bssgp_tx_status(BSSGP_CAUSE_PROTO_ERR_UNSPEC, NULL, msg);
+ break;
+ }
+
+ return rc;
+err_mand_ie:
+ LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(SGSN) missing mandatory IE\n",
+ nsvc->nsei);
+ return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, msg);
+err_no_peer:
+ LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(SGSN) cannot find peer based on RAC\n",
+ nsvc->nsei);
+ return bssgp_tx_status(BSSGP_CAUSE_UNKNOWN_BVCI, NULL, msg);
+}
+
+/* Main input function for Gb proxy */
+int gbprox_rcvmsg(struct msgb *msg, struct gprs_nsvc *nsvc, uint16_t ns_bvci)
+{
+ int rc;
+ struct gbprox_peer *peer;
+
+ /* Only BVCI=0 messages need special treatment */
+ if (ns_bvci == 0 || ns_bvci == 1) {
+ if (nsvc->remote_end_is_sgsn)
+ rc = gbprox_rx_sig_from_sgsn(msg, nsvc, ns_bvci);
+ else
+ rc = gbprox_rx_sig_from_bss(msg, nsvc, ns_bvci);
+ } else {
+ /* All other BVCI are PTP and thus can be simply forwarded */
+ if (!nsvc->remote_end_is_sgsn) {
+ return gbprox_relay2sgsn(msg, ns_bvci);
+ }
+ /* else: SGSN -> BSS direction */
+ peer = peer_by_bvci(ns_bvci);
+ if (!peer) {
+ LOGP(DGPRS, LOGL_INFO, "Allocationg new peer for "
+ "BVCI=%u via NSVC=%u/NSEI=%u\n", ns_bvci,
+ nsvc->nsvci, nsvc->nsei);
+ peer = peer_alloc(ns_bvci);
+ peer->nsvc = nsvc;
+ }
+ if (peer->blocked) {
+ LOGP(DGPRS, LOGL_NOTICE, "Dropping PDU for "
+ "blocked BVCI=%u via NSVC=%u/NSEI=%u\n",
+ ns_bvci, nsvc->nsvci, nsvc->nsei);
+ return bssgp_tx_status(BSSGP_CAUSE_BVCI_BLOCKED, NULL, msg);
+ }
+ rc = gbprox_relay2peer(msg, peer, ns_bvci);
+ }
+
+ return rc;
+}
+
+int gbprox_reset_persistent_nsvcs(struct gprs_ns_inst *nsi)
+{
+ struct gprs_nsvc *nsvc;
+
+ llist_for_each_entry(nsvc, &nsi->gprs_nsvcs, list) {
+ if (!nsvc->persistent)
+ continue;
+ gprs_nsvc_reset(nsvc, NS_CAUSE_OM_INTERVENTION);
+ }
+ return 0;
+}
+
+/* Signal handler for signals from NS layer */
+int gbprox_signal(unsigned int subsys, unsigned int signal,
+ void *handler_data, void *signal_data)
+{
+ struct ns_signal_data *nssd = signal_data;
+ struct gprs_nsvc *nsvc = nssd->nsvc;
+ struct gbprox_peer *peer;
+
+ if (subsys != SS_NS)
+ return 0;
+
+ if (signal == S_NS_RESET && nsvc->nsei == gbcfg.nsip_sgsn_nsei) {
+ /* We have received a NS-RESET from the NSEI and NSVC
+ * of the SGSN. This might happen with SGSN that start
+ * their own NS-RESET procedure without waiting for our
+ * NS-RESET */
+ nsvc->remote_end_is_sgsn = 1;
+ }
+
+ if (signal == S_NS_ALIVE_EXP && nsvc->remote_end_is_sgsn) {
+ LOGP(DGPRS, LOGL_NOTICE, "Tns alive expired too often, "
+ "re-starting RESET procedure\n");
+ nsip_connect(nsvc->nsi, &nsvc->ip.bts_addr, nsvc->nsei,
+ nsvc->nsvci);
+ }
+
+ if (!nsvc->remote_end_is_sgsn) {
+ /* from BSS to SGSN */
+ peer = peer_by_nsvc(nsvc);
+ if (!peer) {
+ LOGP(DGPRS, LOGL_NOTICE, "signal %u for unknown peer "
+ "NSEI=%u/NSVCI=%u\n", signal, nsvc->nsei,
+ nsvc->nsvci);
+ return 0;
+ }
+ switch (signal) {
+ case S_NS_RESET:
+ case S_NS_BLOCK:
+ if (!peer->blocked)
+ break;
+ LOGP(DGPRS, LOGL_NOTICE, "Converting NS_RESET from "
+ "NSEI=%u/NSVCI=%u into BSSGP_BVC_BLOCK to SGSN\n",
+ nsvc->nsei, nsvc->nsvci);
+ bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_BLOCK, nsvc->nsei,
+ peer->bvci, 0);
+ break;
+ }
+ } else {
+ /* iterate over all BTS peers and send the respective PDU */
+ llist_for_each_entry(peer, &gbprox_bts_peers, list) {
+ switch (signal) {
+ case S_NS_RESET:
+ gprs_ns_tx_reset(peer->nsvc, nssd->cause);
+ break;
+ case S_NS_BLOCK:
+ gprs_ns_tx_block(peer->nsvc, nssd->cause);
+ break;
+ case S_NS_UNBLOCK:
+ gprs_ns_tx_unblock(peer->nsvc);
+ break;
+ }
+ }
+ }
+ return 0;
+}
+
+
+#include <osmocom/vty/command.h>
+
+gDEFUN(show_gbproxy, show_gbproxy_cmd, "show gbproxy",
+ SHOW_STR "Display information about the Gb proxy")
+{
+ struct gbprox_peer *peer;
+
+ llist_for_each_entry(peer, &gbprox_bts_peers, list) {
+ struct gprs_nsvc *nsvc = peer->nsvc;
+ struct gprs_ra_id raid;
+ gsm48_parse_ra(&raid, peer->ra);
+
+ vty_out(vty, "NSEI %5u, NS-VC %5u, PTP-BVCI %5u, "
+ "RAC %u-%u-%u-%u",
+ nsvc->nsei, nsvc->nsvci, peer->bvci,
+ raid.mcc, raid.mnc, raid.lac, raid.rac);
+ if (nsvc->ll == GPRS_NS_LL_UDP || nsvc->ll == GPRS_NS_LL_FR_GRE)
+ vty_out(vty, " %s:%u",
+ inet_ntoa(nsvc->ip.bts_addr.sin_addr),
+ ntohs(nsvc->ip.bts_addr.sin_port));
+ if (peer->blocked)
+ vty_out(vty, " [BVC-BLOCKED]");
+
+ vty_out(vty, "%s", VTY_NEWLINE);
+ }
+ return CMD_SUCCESS;
+}