Separation of GPRS PCU application from main OpenBTS code and changing PCU architecture (First step).
1. pcu - main program for GPRS PCU.
2. gprs_rlcmac - RLC/MAC layer implementation for PCU. Added list for TBF, TBF allocation, establishment, release.
3. gprs_bssgp_pcu - BSSGP protocol implementation for PCU.
4. pcu_l1_if - interface for communication PCU application with OpenBTS.
diff --git a/gprs_bssgp_pcu.cpp b/gprs_bssgp_pcu.cpp
new file mode 100644
index 0000000..4ccea44
--- /dev/null
+++ b/gprs_bssgp_pcu.cpp
@@ -0,0 +1,231 @@
+/* gprs_bssgp_pcu.cpp
+ *
+ * Copyright (C) 2012 Ivan Klyuchnikov
+ *
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <gprs_rlcmac.h>
+#include <gprs_bssgp_pcu.h>
+#include <pcu_l1_if.h>
+
+struct sgsn_instance *sgsn;
+void *tall_bsc_ctx;
+struct bssgp_bvc_ctx *bctx = btsctx_alloc(BVCI, NSEI);
+
+int gprs_bssgp_pcu_rx_dl_ud(struct msgb *msg)
+{
+ struct bssgp_ud_hdr *budh;
+ int tfi;
+ int data_index = 0;
+ int i = 0;
+ int pdu_index = 0;
+
+ budh = (struct bssgp_ud_hdr *)msgb_bssgph(msg);
+ struct gprs_rlcmac_tbf *tbf;
+ // Create new TBF
+ tfi = tfi_alloc();
+ if (tfi < 0) {
+ return tfi;
+ }
+ tbf = tbf_alloc(tfi);
+ tbf->direction = GPRS_RLCMAC_DL_TBF;
+ tbf->state = GPRS_RLCMAC_WAIT_DATA_SEQ_START;
+ tbf->tlli = ntohl(budh->tlli);
+
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP TLLI=0x%08x \n", ntohl(budh->tlli));
+ for (i = 4; i < MAX_LEN_PDU; i++)
+ {
+ //LOGP(DBSSGP, LOGL_NOTICE, "SERCH data = -0x%02x\n", budh ->data[i]);
+ if(budh->data[i] == IE_PDU)
+ {
+ pdu_index = i + 2;
+ break;
+ }
+ }
+ for (i = pdu_index; i < pdu_index + (budh->data[pdu_index-1]&0x7f); i++)
+ {
+ //LOGP(DBSSGP, LOGL_NOTICE, "-0x%02x\n", budh ->data[i]);
+ tbf->rlc_data[data_index] = budh->data[i];
+ data_index++;
+ }
+ DEBUGP(DBSSGP, "BSSGP Catch from SGSN=%u octets. Send it to OpenBTS.\n", data_index);
+ gsmtap_send_llc(tbf->rlc_data,data_index);
+ tbf->data_index = data_index;
+ gprs_rlcmac_segment_llc_pdu(tbf);
+}
+
+/* Receive a BSSGP PDU from a BSS on a PTP BVCI */
+int gprs_bssgp_pcu_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;
+ unsigned 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);
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BVC_S_BLOCKED\n");
+ return bssgp_tx_status(BSSGP_CAUSE_BVCI_BLOCKED, &bvci, msg);
+ }
+
+ switch (pdu_type) {
+ case BSSGP_PDUT_DL_UNITDATA:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_DL_UNITDATA\n");
+ gprs_bssgp_pcu_rx_dl_ud(msg);
+ break;
+ case BSSGP_PDUT_PAGING_PS:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_PAGING_PS\n");
+ break;
+ case BSSGP_PDUT_PAGING_CS:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_PAGING_CS\n");
+ break;
+ case BSSGP_PDUT_RA_CAPA_UPDATE_ACK:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_RA_CAPA_UPDATE_ACK\n");
+ break;
+ case BSSGP_PDUT_FLOW_CONTROL_BVC_ACK:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_FLOW_CONTROL_BVC_ACK\n");
+ break;
+ case BSSGP_PDUT_FLOW_CONTROL_MS_ACK:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_FLOW_CONTROL_MS_ACK\n");
+ 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 SGSN on a SIGNALLING BVCI */
+int gprs_bssgp_pcu_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);
+ int rc = 0;
+ switch (bgph->pdu_type) {
+ 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;
+ case BSSGP_PDUT_SUSPEND_ACK:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_SUSPEND_ACK\n");
+ break;
+ case BSSGP_PDUT_SUSPEND_NACK:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_SUSPEND_NACK\n");
+ break;
+ case BSSGP_PDUT_BVC_RESET_ACK:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_BVC_RESET_ACK\n");
+ break;
+ case BSSGP_PDUT_PAGING_PS:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_PAGING_PS\n");
+ break;
+ case BSSGP_PDUT_PAGING_CS:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_PAGING_CS\n");
+ break;
+ case BSSGP_PDUT_RESUME_ACK:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_RESUME_ACK\n");
+ break;
+ case BSSGP_PDUT_RESUME_NACK:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_RESUME_NACK\n");
+ break;
+ case BSSGP_PDUT_FLUSH_LL:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_FLUSH_LL\n");
+ break;
+ case BSSGP_PDUT_BVC_BLOCK_ACK:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_SUSPEND_ACK\n");
+ break;
+ case BSSGP_PDUT_BVC_UNBLOCK_ACK:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_BVC_UNBLOCK_ACK\n");
+ break;
+ case BSSGP_PDUT_SGSN_INVOKE_TRACE:
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BSSGP_PDUT_SGSN_INVOKE_TRACE\n");
+ break;
+ default:
+ DEBUGP(DBSSGP, "BSSGP BVCI=%u Rx PDU type 0x%02x unknown\n", bctx->bvci, bgph->pdu_type);
+ rc = bssgp_tx_status(BSSGP_CAUSE_PROTO_ERR_UNSPEC, NULL, msg);
+ break;
+ }
+ return rc;
+}
+
+int gprs_bssgp_pcu_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;
+ 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)
+ {
+ bctx = btsctx_alloc(ns_bvci, msgb_nsei(msg));
+ }
+
+ if (!bctx && pdu_type != BSSGP_PDUT_BVC_RESET_ACK)
+ {
+ 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)
+ {
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BVCI_SIGNALLING gprs_bssgp_rx_sign\n");
+ rc = gprs_bssgp_pcu_rx_sign(msg, &tp, bctx);
+ }
+ else if (ns_bvci == BVCI_PTM)
+ {
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BVCI_PTM bssgp_tx_status\n");
+ rc = bssgp_tx_status(BSSGP_CAUSE_PDU_INCOMP_FEAT, NULL, msg);
+ }
+ else
+ {
+ LOGP(DBSSGP, LOGL_NOTICE, "rx BVCI_PTP gprs_bssgp_rx_ptp\n");
+ rc = gprs_bssgp_pcu_rx_ptp(msg, &tp, bctx);
+ }
+ return rc;
+}