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diff --git a/src/libgb/gprs_bssgp.c b/src/libgb/gprs_bssgp.c
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+++ b/src/libgb/gprs_bssgp.c
@@ -0,0 +1,856 @@
+/* GPRS BSSGP protocol implementation as per 3GPP TS 08.18 */
+
+/* (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 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/>.
+ *
+ * TODO:
+ * o properly count incoming BVC-RESET packets in counter group
+ * o set log context as early as possible for outgoing packets
+ */
+
+#include <errno.h>
+#include <stdint.h>
+
+#include <netinet/in.h>
+
+#include <osmocore/msgb.h>
+#include <osmocore/tlv.h>
+#include <osmocore/talloc.h>
+#include <osmocore/rate_ctr.h>
+
+#include <openbsc/debug.h>
+#include <openbsc/gsm_data.h>
+#include <openbsc/gsm_04_08_gprs.h>
+#include <openbsc/gprs_bssgp.h>
+#include <openbsc/gprs_llc.h>
+#include <openbsc/gprs_ns.h>
+#include <openbsc/gprs_sgsn.h>
+#include <openbsc/gprs_gmm.h>
+
+void *bssgp_tall_ctx = NULL;
+
+#define BVC_F_BLOCKED 0x0001
+
+enum bssgp_ctr {
+ BSSGP_CTR_PKTS_IN,
+ BSSGP_CTR_PKTS_OUT,
+ BSSGP_CTR_BYTES_IN,
+ BSSGP_CTR_BYTES_OUT,
+ BSSGP_CTR_BLOCKED,
+ BSSGP_CTR_DISCARDED,
+};
+
+static const struct rate_ctr_desc bssgp_ctr_description[] = {
+ { "packets.in", "Packets at BSSGP Level ( In)" },
+ { "packets.out","Packets at BSSGP Level (Out)" },
+ { "bytes.in", "Bytes at BSSGP Level ( In)" },
+ { "bytes.out", "Bytes at BSSGP Level (Out)" },
+ { "blocked", "BVC Blocking count" },
+ { "discarded", "BVC LLC Discarded count" },
+};
+
+static const struct rate_ctr_group_desc bssgp_ctrg_desc = {
+ .group_name_prefix = "bssgp.bss_ctx",
+ .group_description = "BSSGP Peer Statistics",
+ .num_ctr = ARRAY_SIZE(bssgp_ctr_description),
+ .ctr_desc = bssgp_ctr_description,
+};
+
+LLIST_HEAD(bssgp_bvc_ctxts);
+
+/* Find a BTS Context based on parsed RA ID and Cell ID */
+struct bssgp_bvc_ctx *btsctx_by_raid_cid(const struct gprs_ra_id *raid, uint16_t cid)
+{
+ struct bssgp_bvc_ctx *bctx;
+
+ llist_for_each_entry(bctx, &bssgp_bvc_ctxts, list) {
+ if (!memcmp(&bctx->ra_id, raid, sizeof(bctx->ra_id)) &&
+ bctx->cell_id == cid)
+ return bctx;
+ }
+ return NULL;
+}
+
+/* Find a BTS context based on BVCI+NSEI tuple */
+struct bssgp_bvc_ctx *btsctx_by_bvci_nsei(uint16_t bvci, uint16_t nsei)
+{
+ struct bssgp_bvc_ctx *bctx;
+
+ llist_for_each_entry(bctx, &bssgp_bvc_ctxts, list) {
+ if (bctx->nsei == nsei && bctx->bvci == bvci)
+ return bctx;
+ }
+ return NULL;
+}
+
+struct bssgp_bvc_ctx *btsctx_alloc(uint16_t bvci, uint16_t nsei)
+{
+ struct bssgp_bvc_ctx *ctx;
+
+ ctx = talloc_zero(bssgp_tall_ctx, struct bssgp_bvc_ctx);
+ if (!ctx)
+ return NULL;
+ ctx->bvci = bvci;
+ ctx->nsei = nsei;
+ /* FIXME: BVCI is not unique, only BVCI+NSEI ?!? */
+ ctx->ctrg = rate_ctr_group_alloc(ctx, &bssgp_ctrg_desc, bvci);
+
+ llist_add(&ctx->list, &bssgp_bvc_ctxts);
+
+ return ctx;
+}
+
+/* Chapter 10.4.5: Flow Control BVC ACK */
+static int bssgp_tx_fc_bvc_ack(uint16_t nsei, uint8_t tag, uint16_t ns_bvci)
+{
+ struct msgb *msg = bssgp_msgb_alloc();
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_put(msg, sizeof(*bgph));
+
+ msgb_nsei(msg) = nsei;
+ msgb_bvci(msg) = ns_bvci;
+
+ bgph->pdu_type = BSSGP_PDUT_FLOW_CONTROL_BVC_ACK;
+ msgb_tvlv_put(msg, BSSGP_IE_TAG, 1, &tag);
+
+ return gprs_ns_sendmsg(bssgp_nsi, msg);
+}
+
+/* 10.3.7 SUSPEND-ACK PDU */
+int bssgp_tx_suspend_ack(uint16_t nsei, uint32_t tlli,
+ const struct gprs_ra_id *ra_id, uint8_t suspend_ref)
+{
+ struct msgb *msg = bssgp_msgb_alloc();
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_put(msg, sizeof(*bgph));
+ uint32_t _tlli;
+ uint8_t ra[6];
+
+ msgb_nsei(msg) = nsei;
+ msgb_bvci(msg) = 0; /* Signalling */
+ bgph->pdu_type = BSSGP_PDUT_SUSPEND_ACK;
+
+ _tlli = htonl(tlli);
+ msgb_tvlv_put(msg, BSSGP_IE_TLLI, 4, (uint8_t *) &_tlli);
+ gsm48_construct_ra(ra, ra_id);
+ msgb_tvlv_put(msg, BSSGP_IE_ROUTEING_AREA, 6, ra);
+ msgb_tvlv_put(msg, BSSGP_IE_SUSPEND_REF_NR, 1, &suspend_ref);
+
+ return gprs_ns_sendmsg(bssgp_nsi, msg);
+}
+
+/* 10.3.8 SUSPEND-NACK PDU */
+int bssgp_tx_suspend_nack(uint16_t nsei, uint32_t tlli,
+ const struct gprs_ra_id *ra_id,
+ uint8_t *cause)
+{
+ struct msgb *msg = bssgp_msgb_alloc();
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_put(msg, sizeof(*bgph));
+ uint32_t _tlli;
+ uint8_t ra[6];
+
+ msgb_nsei(msg) = nsei;
+ msgb_bvci(msg) = 0; /* Signalling */
+ bgph->pdu_type = BSSGP_PDUT_SUSPEND_NACK;
+
+ _tlli = htonl(tlli);
+ msgb_tvlv_put(msg, BSSGP_IE_TLLI, 4, (uint8_t *) &_tlli);
+ gsm48_construct_ra(ra, ra_id);
+ msgb_tvlv_put(msg, BSSGP_IE_ROUTEING_AREA, 6, ra);
+ if (cause)
+ msgb_tvlv_put(msg, BSSGP_IE_CAUSE, 1, cause);
+
+ return gprs_ns_sendmsg(bssgp_nsi, msg);
+}
+
+/* 10.3.10 RESUME-ACK PDU */
+int bssgp_tx_resume_ack(uint16_t nsei, uint32_t tlli,
+ const struct gprs_ra_id *ra_id)
+{
+ struct msgb *msg = bssgp_msgb_alloc();
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_put(msg, sizeof(*bgph));
+ uint32_t _tlli;
+ uint8_t ra[6];
+
+ msgb_nsei(msg) = nsei;
+ msgb_bvci(msg) = 0; /* Signalling */
+ bgph->pdu_type = BSSGP_PDUT_RESUME_ACK;
+
+ _tlli = htonl(tlli);
+ msgb_tvlv_put(msg, BSSGP_IE_TLLI, 4, (uint8_t *) &_tlli);
+ gsm48_construct_ra(ra, ra_id);
+ msgb_tvlv_put(msg, BSSGP_IE_ROUTEING_AREA, 6, ra);
+
+ return gprs_ns_sendmsg(bssgp_nsi, msg);
+}
+
+/* 10.3.11 RESUME-NACK PDU */
+int bssgp_tx_resume_nack(uint16_t nsei, uint32_t tlli,
+ const struct gprs_ra_id *ra_id, uint8_t *cause)
+{
+ struct msgb *msg = bssgp_msgb_alloc();
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_put(msg, sizeof(*bgph));
+ uint32_t _tlli;
+ uint8_t ra[6];
+
+ msgb_nsei(msg) = nsei;
+ msgb_bvci(msg) = 0; /* Signalling */
+ bgph->pdu_type = BSSGP_PDUT_SUSPEND_NACK;
+
+ _tlli = htonl(tlli);
+ msgb_tvlv_put(msg, BSSGP_IE_TLLI, 4, (uint8_t *) &_tlli);
+ gsm48_construct_ra(ra, ra_id);
+ msgb_tvlv_put(msg, BSSGP_IE_ROUTEING_AREA, 6, ra);
+ if (cause)
+ msgb_tvlv_put(msg, BSSGP_IE_CAUSE, 1, cause);
+
+ return gprs_ns_sendmsg(bssgp_nsi, msg);
+}
+
+uint16_t bssgp_parse_cell_id(struct gprs_ra_id *raid, const uint8_t *buf)
+{
+ /* 6 octets RAC */
+ gsm48_parse_ra(raid, buf);
+ /* 2 octets CID */
+ return ntohs(*(uint16_t *) (buf+6));
+}
+
+/* Chapter 8.4 BVC-Reset Procedure */
+static int bssgp_rx_bvc_reset(struct msgb *msg, struct tlv_parsed *tp,
+ uint16_t ns_bvci)
+{
+ struct bssgp_bvc_ctx *bctx;
+ uint16_t nsei = msgb_nsei(msg);
+ uint16_t bvci;
+ int rc;
+
+ bvci = ntohs(*(uint16_t *)TLVP_VAL(tp, BSSGP_IE_BVCI));
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx RESET cause=%s\n", bvci,
+ bssgp_cause_str(*TLVP_VAL(tp, BSSGP_IE_CAUSE)));
+
+ /* look-up or create the BTS context for this BVC */
+ bctx = btsctx_by_bvci_nsei(bvci, nsei);
+ if (!bctx)
+ bctx = btsctx_alloc(bvci, nsei);
+
+ /* As opposed to NS-VCs, BVCs are NOT blocked after RESET */
+ bctx->state &= ~BVC_S_BLOCKED;
+
+ /* When we receive a BVC-RESET PDU (at least of a PTP BVCI), the BSS
+ * informs us about its RAC + Cell ID, so we can create a mapping */
+ if (bvci != 0 && bvci != 1) {
+ if (!TLVP_PRESENT(tp, BSSGP_IE_CELL_ID)) {
+ LOGP(DBSSGP, LOGL_ERROR, "BSSGP BVCI=%u RESET "
+ "missing mandatory IE\n", bvci);
+ return -EINVAL;
+ }
+ /* actually extract RAC / CID */
+ bctx->cell_id = bssgp_parse_cell_id(&bctx->ra_id,
+ TLVP_VAL(tp, BSSGP_IE_CELL_ID));
+ LOGP(DBSSGP, LOGL_NOTICE, "Cell %u-%u-%u-%u CI %u on BVCI %u\n",
+ bctx->ra_id.mcc, bctx->ra_id.mnc, bctx->ra_id.lac,
+ bctx->ra_id.rac, bctx->cell_id, bvci);
+ }
+
+ /* Acknowledge the RESET to the BTS */
+ rc = bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_RESET_ACK,
+ nsei, bvci, ns_bvci);
+ return 0;
+}
+
+static int bssgp_rx_bvc_block(struct msgb *msg, struct tlv_parsed *tp)
+{
+ uint16_t bvci;
+ struct bssgp_bvc_ctx *ptp_ctx;
+
+ bvci = ntohs(*(uint16_t *)TLVP_VAL(tp, BSSGP_IE_BVCI));
+ if (bvci == BVCI_SIGNALLING) {
+ /* 8.3.2: Signalling BVC shall never be blocked */
+ LOGP(DBSSGP, LOGL_ERROR, "NSEI=%u/BVCI=%u "
+ "received block for signalling BVC!?!\n",
+ msgb_nsei(msg), msgb_bvci(msg));
+ return 0;
+ }
+
+ LOGP(DBSSGP, LOGL_INFO, "BSSGP BVCI=%u BVC-BLOCK\n", bvci);
+
+ ptp_ctx = btsctx_by_bvci_nsei(bvci, msgb_nsei(msg));
+ if (!ptp_ctx)
+ return bssgp_tx_status(BSSGP_CAUSE_UNKNOWN_BVCI, &bvci, msg);
+
+ ptp_ctx->state |= BVC_S_BLOCKED;
+ rate_ctr_inc(&ptp_ctx->ctrg->ctr[BSSGP_CTR_BLOCKED]);
+
+ /* FIXME: Send NM_BVC_BLOCK.ind to NM */
+
+ /* We always acknowledge the BLOCKing */
+ return bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_BLOCK_ACK, msgb_nsei(msg),
+ bvci, msgb_bvci(msg));
+};
+
+static int bssgp_rx_bvc_unblock(struct msgb *msg, struct tlv_parsed *tp)
+{
+ uint16_t bvci;
+ struct bssgp_bvc_ctx *ptp_ctx;
+
+ bvci = ntohs(*(uint16_t *)TLVP_VAL(tp, BSSGP_IE_BVCI));
+ if (bvci == BVCI_SIGNALLING) {
+ /* 8.3.2: Signalling BVC shall never be blocked */
+ LOGP(DBSSGP, LOGL_ERROR, "NSEI=%u/BVCI=%u "
+ "received unblock for signalling BVC!?!\n",
+ msgb_nsei(msg), msgb_bvci(msg));
+ return 0;
+ }
+
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx BVC-UNBLOCK\n", bvci);
+
+ ptp_ctx = btsctx_by_bvci_nsei(bvci, msgb_nsei(msg));
+ if (!ptp_ctx)
+ return bssgp_tx_status(BSSGP_CAUSE_UNKNOWN_BVCI, &bvci, msg);
+
+ ptp_ctx->state &= ~BVC_S_BLOCKED;
+
+ /* FIXME: Send NM_BVC_UNBLOCK.ind to NM */
+
+ /* We always acknowledge the unBLOCKing */
+ return bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_UNBLOCK_ACK, msgb_nsei(msg),
+ bvci, msgb_bvci(msg));
+};
+
+/* Uplink unit-data */
+static int bssgp_rx_ul_ud(struct msgb *msg, struct tlv_parsed *tp,
+ struct bssgp_bvc_ctx *ctx)
+{
+ struct bssgp_ud_hdr *budh = (struct bssgp_ud_hdr *) msgb_bssgph(msg);
+
+ /* extract TLLI and parse TLV IEs */
+ msgb_tlli(msg) = ntohl(budh->tlli);
+
+ DEBUGP(DBSSGP, "BSSGP TLLI=0x%08x UPLINK-UNITDATA\n", msgb_tlli(msg));
+
+ /* Cell ID and LLC_PDU are the only mandatory IE */
+ if (!TLVP_PRESENT(tp, BSSGP_IE_CELL_ID) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_LLC_PDU)) {
+ LOGP(DBSSGP, LOGL_ERROR, "BSSGP TLLI=0x%08x Rx UL-UD "
+ "missing mandatory IE\n", msgb_tlli(msg));
+ return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, msg);
+ }
+
+ /* store pointer to LLC header and CELL ID in msgb->cb */
+ msgb_llch(msg) = (uint8_t *) TLVP_VAL(tp, BSSGP_IE_LLC_PDU);
+ msgb_bcid(msg) = (uint8_t *) TLVP_VAL(tp, BSSGP_IE_CELL_ID);
+
+ return gprs_llc_rcvmsg(msg, tp);
+}
+
+static int bssgp_rx_suspend(struct msgb *msg, struct tlv_parsed *tp,
+ struct bssgp_bvc_ctx *ctx)
+{
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_bssgph(msg);
+ struct gprs_ra_id raid;
+ uint32_t tlli;
+ int rc;
+
+ if (!TLVP_PRESENT(tp, BSSGP_IE_TLLI) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_ROUTEING_AREA)) {
+ LOGP(DBSSGP, LOGL_ERROR, "BSSGP BVCI=%u Rx SUSPEND "
+ "missing mandatory IE\n", ctx->bvci);
+ return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, msg);
+ }
+
+ tlli = ntohl(*(uint32_t *)TLVP_VAL(tp, BSSGP_IE_TLLI));
+
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u TLLI=0x%08x Rx SUSPEND\n",
+ ctx->bvci, tlli);
+
+ gsm48_parse_ra(&raid, TLVP_VAL(tp, BSSGP_IE_ROUTEING_AREA));
+
+ /* Inform GMM about the SUSPEND request */
+ rc = gprs_gmm_rx_suspend(&raid, tlli);
+ if (rc < 0)
+ return bssgp_tx_suspend_nack(msgb_nsei(msg), tlli, &raid, NULL);
+
+ bssgp_tx_suspend_ack(msgb_nsei(msg), tlli, &raid, 0);
+
+ return 0;
+}
+
+static int bssgp_rx_resume(struct msgb *msg, struct tlv_parsed *tp,
+ struct bssgp_bvc_ctx *ctx)
+{
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_bssgph(msg);
+ struct gprs_ra_id raid;
+ uint32_t tlli;
+ uint8_t suspend_ref;
+ int rc;
+
+ if (!TLVP_PRESENT(tp, BSSGP_IE_TLLI) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_ROUTEING_AREA) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_SUSPEND_REF_NR)) {
+ LOGP(DBSSGP, LOGL_ERROR, "BSSGP BVCI=%u Rx RESUME "
+ "missing mandatory IE\n", ctx->bvci);
+ return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, msg);
+ }
+
+ tlli = ntohl(*(uint32_t *)TLVP_VAL(tp, BSSGP_IE_TLLI));
+ suspend_ref = *TLVP_VAL(tp, BSSGP_IE_SUSPEND_REF_NR);
+
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u TLLI=0x%08x RESUME\n", ctx->bvci, tlli);
+
+ gsm48_parse_ra(&raid, TLVP_VAL(tp, BSSGP_IE_ROUTEING_AREA));
+
+ /* Inform GMM about the RESUME request */
+ rc = gprs_gmm_rx_resume(&raid, tlli, suspend_ref);
+ if (rc < 0)
+ return bssgp_tx_resume_nack(msgb_nsei(msg), tlli, &raid,
+ NULL);
+
+ bssgp_tx_resume_ack(msgb_nsei(msg), tlli, &raid);
+ return 0;
+}
+
+
+static int bssgp_rx_llc_disc(struct msgb *msg, struct tlv_parsed *tp,
+ struct bssgp_bvc_ctx *ctx)
+{
+ uint32_t tlli = 0;
+
+ if (!TLVP_PRESENT(tp, BSSGP_IE_TLLI) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_LLC_FRAMES_DISCARDED) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_BVCI) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_NUM_OCT_AFF)) {
+ LOGP(DBSSGP, LOGL_ERROR, "BSSGP BVCI=%u Rx LLC DISCARDED "
+ "missing mandatory IE\n", ctx->bvci);
+ }
+
+ if (TLVP_PRESENT(tp, BSSGP_IE_TLLI))
+ tlli = ntohl(*(uint32_t *)TLVP_VAL(tp, BSSGP_IE_TLLI));
+
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u TLLI=%08x LLC DISCARDED\n",
+ ctx->bvci, tlli);
+
+ rate_ctr_inc(&ctx->ctrg->ctr[BSSGP_CTR_DISCARDED]);
+
+ /* FIXME: send NM_LLC_DISCARDED to NM */
+ return 0;
+}
+
+static int bssgp_rx_fc_bvc(struct msgb *msg, struct tlv_parsed *tp,
+ struct bssgp_bvc_ctx *bctx)
+{
+
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx Flow Control BVC\n",
+ bctx->bvci);
+
+ if (!TLVP_PRESENT(tp, BSSGP_IE_TAG) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_BVC_BUCKET_SIZE) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_BUCKET_LEAK_RATE) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_BMAX_DEFAULT_MS) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_R_DEFAULT_MS)) {
+ LOGP(DBSSGP, LOGL_ERROR, "BSSGP BVCI=%u Rx FC BVC "
+ "missing mandatory IE\n", bctx->bvci);
+ return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, msg);
+ }
+
+ /* FIXME: actually implement flow control */
+
+ /* Send FLOW_CONTROL_BVC_ACK */
+ return bssgp_tx_fc_bvc_ack(msgb_nsei(msg), *TLVP_VAL(tp, BSSGP_IE_TAG),
+ msgb_bvci(msg));
+}
+
+/* Receive a BSSGP PDU from a BSS on a PTP BVCI */
+static int gprs_bssgp_rx_ptp(struct msgb *msg, struct tlv_parsed *tp,
+ struct bssgp_bvc_ctx *bctx)
+{
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_bssgph(msg);
+ uint8_t pdu_type = bgph->pdu_type;
+ int rc = 0;
+
+ /* If traffic is received on a BVC that is marked as blocked, the
+ * received PDU shall not be accepted and a STATUS PDU (Cause value:
+ * BVC Blocked) shall be sent to the peer entity on the signalling BVC */
+ if (bctx->state & BVC_S_BLOCKED && pdu_type != BSSGP_PDUT_STATUS) {
+ uint16_t bvci = msgb_bvci(msg);
+ return bssgp_tx_status(BSSGP_CAUSE_BVCI_BLOCKED, &bvci, msg);
+ }
+
+ switch (pdu_type) {
+ case BSSGP_PDUT_UL_UNITDATA:
+ /* some LLC data from the MS */
+ rc = bssgp_rx_ul_ud(msg, tp, bctx);
+ break;
+ case BSSGP_PDUT_RA_CAPABILITY:
+ /* BSS requests RA capability or IMSI */
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx RA CAPABILITY UPDATE\n",
+ bctx->bvci);
+ /* FIXME: send GMM_RA_CAPABILITY_UPDATE.ind to GMM */
+ /* FIXME: send RA_CAPA_UPDATE_ACK */
+ break;
+ case BSSGP_PDUT_RADIO_STATUS:
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx RADIO STATUS\n", bctx->bvci);
+ /* BSS informs us of some exception */
+ /* FIXME: send GMM_RADIO_STATUS.ind to GMM */
+ break;
+ case BSSGP_PDUT_FLOW_CONTROL_BVC:
+ /* BSS informs us of available bandwidth in Gb interface */
+ rc = bssgp_rx_fc_bvc(msg, tp, bctx);
+ break;
+ case BSSGP_PDUT_FLOW_CONTROL_MS:
+ /* BSS informs us of available bandwidth to one MS */
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx Flow Control MS\n",
+ bctx->bvci);
+ /* FIXME: actually implement flow control */
+ /* FIXME: Send FLOW_CONTROL_MS_ACK */
+ break;
+ case BSSGP_PDUT_STATUS:
+ /* Some exception has occurred */
+ /* FIXME: send NM_STATUS.ind to NM */
+ case BSSGP_PDUT_DOWNLOAD_BSS_PFC:
+ case BSSGP_PDUT_CREATE_BSS_PFC_ACK:
+ case BSSGP_PDUT_CREATE_BSS_PFC_NACK:
+ case BSSGP_PDUT_MODIFY_BSS_PFC:
+ case BSSGP_PDUT_DELETE_BSS_PFC_ACK:
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx PDU type 0x%02x not [yet] "
+ "implemented\n", bctx->bvci, pdu_type);
+ rc = bssgp_tx_status(BSSGP_CAUSE_PDU_INCOMP_FEAT, NULL, msg);
+ break;
+ /* those only exist in the SGSN -> BSS direction */
+ case BSSGP_PDUT_DL_UNITDATA:
+ case BSSGP_PDUT_PAGING_PS:
+ case BSSGP_PDUT_PAGING_CS:
+ case BSSGP_PDUT_RA_CAPA_UPDATE_ACK:
+ case BSSGP_PDUT_FLOW_CONTROL_BVC_ACK:
+ case BSSGP_PDUT_FLOW_CONTROL_MS_ACK:
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u PDU type 0x%02x only exists "
+ "in DL\n", bctx->bvci, pdu_type);
+ bssgp_tx_status(BSSGP_CAUSE_PROTO_ERR_UNSPEC, NULL, msg);
+ rc = -EINVAL;
+ break;
+ default:
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u PDU type 0x%02x unknown\n",
+ bctx->bvci, pdu_type);
+ rc = bssgp_tx_status(BSSGP_CAUSE_PROTO_ERR_UNSPEC, NULL, msg);
+ break;
+ }
+
+ return rc;
+}
+
+/* Receive a BSSGP PDU from a BSS on a SIGNALLING BVCI */
+static int gprs_bssgp_rx_sign(struct msgb *msg, struct tlv_parsed *tp,
+ struct bssgp_bvc_ctx *bctx)
+{
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_bssgph(msg);
+ uint8_t pdu_type = bgph->pdu_type;
+ int rc = 0;
+ uint16_t ns_bvci = msgb_bvci(msg);
+ uint16_t bvci;
+
+ switch (bgph->pdu_type) {
+ case BSSGP_PDUT_SUSPEND:
+ /* MS wants to suspend */
+ rc = bssgp_rx_suspend(msg, tp, bctx);
+ break;
+ case BSSGP_PDUT_RESUME:
+ /* MS wants to resume */
+ rc = bssgp_rx_resume(msg, tp, bctx);
+ break;
+ case BSSGP_PDUT_FLUSH_LL_ACK:
+ /* BSS informs us it has performed LL FLUSH */
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx FLUSH LL ACK\n", bctx->bvci);
+ /* FIXME: send NM_FLUSH_LL.res to NM */
+ break;
+ case BSSGP_PDUT_LLC_DISCARD:
+ /* BSS informs that some LLC PDU's have been discarded */
+ rc = bssgp_rx_llc_disc(msg, tp, bctx);
+ break;
+ case BSSGP_PDUT_BVC_BLOCK:
+ /* BSS tells us that BVC shall be blocked */
+ if (!TLVP_PRESENT(tp, BSSGP_IE_BVCI) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_CAUSE)) {
+ LOGP(DBSSGP, LOGL_ERROR, "BSSGP Rx BVC-BLOCK "
+ "missing mandatory IE\n");
+ goto err_mand_ie;
+ }
+ rc = bssgp_rx_bvc_block(msg, tp);
+ break;
+ case BSSGP_PDUT_BVC_UNBLOCK:
+ /* BSS tells us that BVC shall be unblocked */
+ if (!TLVP_PRESENT(tp, BSSGP_IE_BVCI)) {
+ LOGP(DBSSGP, LOGL_ERROR, "BSSGP Rx BVC-UNBLOCK "
+ "missing mandatory IE\n");
+ goto err_mand_ie;
+ }
+ rc = bssgp_rx_bvc_unblock(msg, tp);
+ break;
+ case BSSGP_PDUT_BVC_RESET:
+ /* BSS tells us that BVC init is required */
+ if (!TLVP_PRESENT(tp, BSSGP_IE_BVCI) ||
+ !TLVP_PRESENT(tp, BSSGP_IE_CAUSE)) {
+ LOGP(DBSSGP, LOGL_ERROR, "BSSGP Rx BVC-RESET "
+ "missing mandatory IE\n");
+ goto err_mand_ie;
+ }
+ rc = bssgp_rx_bvc_reset(msg, tp, ns_bvci);
+ break;
+ case BSSGP_PDUT_STATUS:
+ /* Some exception has occurred */
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx BVC STATUS\n", bctx->bvci);
+ /* FIXME: send NM_STATUS.ind to NM */
+ break;
+ /* those only exist in the SGSN -> BSS direction */
+ case BSSGP_PDUT_PAGING_PS:
+ case BSSGP_PDUT_PAGING_CS:
+ case BSSGP_PDUT_SUSPEND_ACK:
+ case BSSGP_PDUT_SUSPEND_NACK:
+ case BSSGP_PDUT_RESUME_ACK:
+ case BSSGP_PDUT_RESUME_NACK:
+ case BSSGP_PDUT_FLUSH_LL:
+ case BSSGP_PDUT_BVC_BLOCK_ACK:
+ case BSSGP_PDUT_BVC_UNBLOCK_ACK:
+ case BSSGP_PDUT_SGSN_INVOKE_TRACE:
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx PDU type 0x%02x only exists "
+ "in DL\n", bctx->bvci, pdu_type);
+ bssgp_tx_status(BSSGP_CAUSE_PROTO_ERR_UNSPEC, NULL, msg);
+ rc = -EINVAL;
+ break;
+ default:
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx PDU type 0x%02x unknown\n",
+ bctx->bvci, pdu_type);
+ rc = bssgp_tx_status(BSSGP_CAUSE_PROTO_ERR_UNSPEC, NULL, msg);
+ break;
+ }
+
+ return rc;
+err_mand_ie:
+ return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, msg);
+}
+
+/* We expect msgb_bssgph() to point to the BSSGP header */
+int gprs_bssgp_rcvmsg(struct msgb *msg)
+{
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_bssgph(msg);
+ struct bssgp_ud_hdr *budh = (struct bssgp_ud_hdr *) msgb_bssgph(msg);
+ struct tlv_parsed tp;
+ struct bssgp_bvc_ctx *bctx;
+ uint8_t pdu_type = bgph->pdu_type;
+ uint16_t ns_bvci = msgb_bvci(msg);
+ int data_len;
+ int rc = 0;
+
+ /* Identifiers from DOWN: NSEI, BVCI (both in msg->cb) */
+
+ /* UNITDATA BSSGP headers have TLLI in front */
+ if (pdu_type != BSSGP_PDUT_UL_UNITDATA &&
+ pdu_type != BSSGP_PDUT_DL_UNITDATA) {
+ data_len = msgb_bssgp_len(msg) - sizeof(*bgph);
+ rc = bssgp_tlv_parse(&tp, bgph->data, data_len);
+ } else {
+ data_len = msgb_bssgp_len(msg) - sizeof(*budh);
+ rc = bssgp_tlv_parse(&tp, budh->data, data_len);
+ }
+
+ /* look-up or create the BTS context for this BVC */
+ bctx = btsctx_by_bvci_nsei(ns_bvci, msgb_nsei(msg));
+ /* Only a RESET PDU can create a new BVC context */
+ if (!bctx && pdu_type != BSSGP_PDUT_BVC_RESET) {
+ LOGP(DBSSGP, LOGL_NOTICE, "NSEI=%u/BVCI=%u Rejecting PDU "
+ "type %u for unknown BVCI\n", msgb_nsei(msg), ns_bvci,
+ pdu_type);
+ return bssgp_tx_status(BSSGP_CAUSE_UNKNOWN_BVCI, NULL, msg);
+ }
+
+ if (bctx) {
+ log_set_context(BSC_CTX_BVC, bctx);
+ rate_ctr_inc(&bctx->ctrg->ctr[BSSGP_CTR_PKTS_IN]);
+ rate_ctr_add(&bctx->ctrg->ctr[BSSGP_CTR_BYTES_IN],
+ msgb_bssgp_len(msg));
+ }
+
+ if (ns_bvci == BVCI_SIGNALLING)
+ rc = gprs_bssgp_rx_sign(msg, &tp, bctx);
+ else if (ns_bvci == BVCI_PTM)
+ rc = bssgp_tx_status(BSSGP_CAUSE_PDU_INCOMP_FEAT, NULL, msg);
+ else
+ rc = gprs_bssgp_rx_ptp(msg, &tp, bctx);
+
+ return rc;
+}
+
+/* Entry function from upper level (LLC), asking us to transmit a BSSGP PDU
+ * to a remote MS (identified by TLLI) at a BTS identified by its BVCI and NSEI */
+int gprs_bssgp_tx_dl_ud(struct msgb *msg, struct sgsn_mm_ctx *mmctx)
+{
+ struct bssgp_bvc_ctx *bctx;
+ struct bssgp_ud_hdr *budh;
+ uint8_t llc_pdu_tlv_hdr_len = 2;
+ uint8_t *llc_pdu_tlv, *qos_profile;
+ uint16_t pdu_lifetime = 1000; /* centi-seconds */
+ uint8_t qos_profile_default[3] = { 0x00, 0x00, 0x20 };
+ uint16_t msg_len = msg->len;
+ uint16_t bvci = msgb_bvci(msg);
+ uint16_t nsei = msgb_nsei(msg);
+ uint16_t drx_params;
+
+ /* Identifiers from UP: TLLI, BVCI, NSEI (all in msgb->cb) */
+ if (bvci <= BVCI_PTM ) {
+ LOGP(DBSSGP, LOGL_ERROR, "Cannot send DL-UD to BVCI %u\n",
+ bvci);
+ return -EINVAL;
+ }
+
+ bctx = btsctx_by_bvci_nsei(bvci, nsei);
+ if (!bctx) {
+ /* FIXME: don't simply create missing context, but reject message */
+ bctx = btsctx_alloc(bvci, nsei);
+ }
+
+ if (msg->len > TVLV_MAX_ONEBYTE)
+ llc_pdu_tlv_hdr_len += 1;
+
+ /* prepend the tag and length of the LLC-PDU TLV */
+ llc_pdu_tlv = msgb_push(msg, llc_pdu_tlv_hdr_len);
+ llc_pdu_tlv[0] = BSSGP_IE_LLC_PDU;
+ if (llc_pdu_tlv_hdr_len > 2) {
+ llc_pdu_tlv[1] = msg_len >> 8;
+ llc_pdu_tlv[2] = msg_len & 0xff;
+ } else {
+ llc_pdu_tlv[1] = msg_len & 0x7f;
+ llc_pdu_tlv[1] |= 0x80;
+ }
+
+ /* FIXME: optional elements: Alignment, UTRAN CCO, LSA, PFI */
+
+ if (mmctx) {
+ /* Old TLLI to help BSS map from old->new */
+#if 0
+ if (mmctx->tlli_old)
+ msgb_tvlv_push(msg, BSSGP_IE_TLLI, 4, htonl(*tlli_old));
+#endif
+
+ /* IMSI */
+ if (strlen(mmctx->imsi)) {
+ uint8_t mi[10];
+ int imsi_len = gsm48_generate_mid_from_imsi(mi, mmctx->imsi);
+ if (imsi_len > 2)
+ msgb_tvlv_push(msg, BSSGP_IE_IMSI,
+ imsi_len-2, mi+2);
+ }
+
+ /* DRX parameters */
+ drx_params = htons(mmctx->drx_parms);
+ msgb_tvlv_push(msg, BSSGP_IE_DRX_PARAMS, 2,
+ (uint8_t *) &drx_params);
+
+ /* FIXME: Priority */
+
+ /* MS Radio Access Capability */
+ if (mmctx->ms_radio_access_capa.len)
+ msgb_tvlv_push(msg, BSSGP_IE_MS_RADIO_ACCESS_CAP,
+ mmctx->ms_radio_access_capa.len,
+ mmctx->ms_radio_access_capa.buf);
+ }
+
+ /* prepend the pdu lifetime */
+ pdu_lifetime = htons(pdu_lifetime);
+ msgb_tvlv_push(msg, BSSGP_IE_PDU_LIFETIME, 2, (uint8_t *)&pdu_lifetime);
+
+ /* prepend the QoS profile, TLLI and pdu type */
+ budh = (struct bssgp_ud_hdr *) msgb_push(msg, sizeof(*budh));
+ memcpy(budh->qos_profile, qos_profile_default, sizeof(qos_profile_default));
+ budh->tlli = htonl(msgb_tlli(msg));
+ budh->pdu_type = BSSGP_PDUT_DL_UNITDATA;
+
+ rate_ctr_inc(&bctx->ctrg->ctr[BSSGP_CTR_PKTS_OUT]);
+ rate_ctr_add(&bctx->ctrg->ctr[BSSGP_CTR_BYTES_OUT], msg->len);
+
+ /* Identifiers down: BVCI, NSEI (in msgb->cb) */
+
+ return gprs_ns_sendmsg(bssgp_nsi, msg);
+}
+
+/* Send a single GMM-PAGING.req to a given NSEI/NS-BVCI */
+int gprs_bssgp_tx_paging(uint16_t nsei, uint16_t ns_bvci,
+ struct bssgp_paging_info *pinfo)
+{
+ struct msgb *msg = bssgp_msgb_alloc();
+ struct bssgp_normal_hdr *bgph =
+ (struct bssgp_normal_hdr *) msgb_put(msg, sizeof(*bgph));
+ uint16_t drx_params = htons(pinfo->drx_params);
+ uint8_t mi[10];
+ int imsi_len = gsm48_generate_mid_from_imsi(mi, pinfo->imsi);
+ uint8_t ra[6];
+
+ if (imsi_len < 2)
+ return -EINVAL;
+
+ msgb_nsei(msg) = nsei;
+ msgb_bvci(msg) = ns_bvci;
+
+ if (pinfo->mode == BSSGP_PAGING_PS)
+ bgph->pdu_type = BSSGP_PDUT_PAGING_PS;
+ else
+ bgph->pdu_type = BSSGP_PDUT_PAGING_CS;
+ /* IMSI */
+ msgb_tvlv_put(msg, BSSGP_IE_IMSI, imsi_len-2, mi+2);
+ /* DRX Parameters */
+ msgb_tvlv_put(msg, BSSGP_IE_DRX_PARAMS, 2,
+ (uint8_t *) &drx_params);
+ /* Scope */
+ switch (pinfo->scope) {
+ case BSSGP_PAGING_BSS_AREA:
+ {
+ uint8_t null = 0;
+ msgb_tvlv_put(msg, BSSGP_IE_BSS_AREA_ID, 1, &null);
+ }
+ break;
+ case BSSGP_PAGING_LOCATION_AREA:
+ gsm48_construct_ra(ra, &pinfo->raid);
+ msgb_tvlv_put(msg, BSSGP_IE_LOCATION_AREA, 4, ra);
+ break;
+ case BSSGP_PAGING_ROUTEING_AREA:
+ gsm48_construct_ra(ra, &pinfo->raid);
+ msgb_tvlv_put(msg, BSSGP_IE_ROUTEING_AREA, 6, ra);
+ break;
+ case BSSGP_PAGING_BVCI:
+ {
+ uint16_t bvci = htons(pinfo->bvci);
+ msgb_tvlv_put(msg, BSSGP_IE_BVCI, 2, (uint8_t *)&bvci);
+ }
+ break;
+ }
+ /* QoS profile mandatory for PS */
+ if (pinfo->mode == BSSGP_PAGING_PS)
+ msgb_tvlv_put(msg, BSSGP_IE_QOS_PROFILE, 3, pinfo->qos);
+
+ /* Optional (P-)TMSI */
+ if (pinfo->ptmsi) {
+ uint32_t ptmsi = htonl(*pinfo->ptmsi);
+ msgb_tvlv_put(msg, BSSGP_IE_TMSI, 4, (uint8_t *) &ptmsi);
+ }
+
+ return gprs_ns_sendmsg(bssgp_nsi, msg);
+}