| /* bssgp.cpp |
| * |
| * Copyright (C) 2011 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 <arpa/inet.h> |
| #include <Threads.h> |
| #include "GPRSSocket.h" |
| #include "gsm_rlcmac.h" |
| #include "bssgp.h" |
| |
| // TODO: We should move this parameters to config file. |
| #define SGSN_IP "127.0.0.1" |
| #define SGSN_PORT 23000 |
| #define CELL_ID 3 |
| #define BVCI 7 |
| #define NSEI 3 |
| #define NSVCI 4 |
| #define MNC 1 |
| #define MCC 1 |
| #define LAC 1000 |
| #define RAC 1 |
| |
| #define QOS_PROFILE 0 |
| #define BSSGP_HDR_LEN 20 |
| #define NS_HDR_LEN 4 |
| #define MAX_LEN_PDU 100 |
| #define IE_PDU 14 |
| #define BLOCK_DATA_LEN 19 |
| |
| #define BLOCK_LEN 23 |
| |
| uint16_t bvci = BVCI; |
| uint16_t nsei = NSEI; |
| uint8_t TFI; |
| struct bssgp_bvc_ctx *bctx = btsctx_alloc(bvci, nsei); |
| struct gprs_nsvc *nsvc; |
| struct gprs_ns_inst *sgsn_nsi; |
| struct sgsn_instance *sgsn; |
| void *tall_bsc_ctx; |
| |
| // Send RLC data to OpenBTS. |
| void sendRLC(uint32_t tlli, uint8_t *pdu, unsigned startIndex, unsigned endIndex, unsigned bsn, unsigned fbi) |
| { |
| unsigned spareLen = 0; |
| BitVector resultVector(BLOCK_LEN*8); |
| resultVector.unhex("2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); |
| RlcMacDownlinkDataBlock_t * dataBlock = (RlcMacDownlinkDataBlock_t *)malloc(sizeof(RlcMacDownlinkDataBlock_t)); |
| dataBlock->PAYLOAD_TYPE = 0; |
| dataBlock->RRBP = 0; |
| dataBlock->SP = 1; |
| dataBlock->USF = 1; |
| dataBlock->PR = 0; |
| dataBlock->TFI = 20; |
| dataBlock->FBI = fbi; |
| dataBlock->BSN = bsn; |
| if ((endIndex-startIndex) < 20) |
| { |
| dataBlock->E_1 = 0; |
| dataBlock->LENGTH_INDICATOR[0] = endIndex-startIndex; |
| dataBlock->M[0] = 0; |
| dataBlock->E[0] = 1; |
| spareLen = 19 - dataBlock->LENGTH_INDICATOR[0]; |
| } |
| else |
| { |
| dataBlock->E_1 = 1; |
| } |
| unsigned j = 0; |
| for(unsigned i = startIndex; i < endIndex; i++) |
| { |
| dataBlock->RLC_DATA[j] = pdu[i]; |
| j++; |
| } |
| for(unsigned i = j; i < j + spareLen; i++) |
| { |
| dataBlock->RLC_DATA[i] = 0x2b; |
| } |
| encode_gsm_rlcmac_downlink_data(&resultVector, dataBlock); |
| free(dataBlock); |
| sendToOpenBTS(&resultVector); |
| } |
| |
| /* Receive a BSSGP PDU from a BSS on a PTP BVCI */ |
| int gprs_bssgp_bss_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; |
| uint8_t pdu[MAX_LEN_PDU]; |
| unsigned rc = 0; |
| unsigned dataIndex = 0; |
| unsigned numBlocks = 0; |
| unsigned i = 0; |
| unsigned j = 0; |
| unsigned pduIndex = 0; |
| unsigned fbi = 0; |
| struct bssgp_ud_hdr *budh; |
| |
| /* 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"); |
| budh = (struct bssgp_ud_hdr *) msgb_bssgph(msg); |
| 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) |
| { |
| pduIndex = i+2; |
| break; |
| } |
| } |
| for (i = pduIndex; i < pduIndex + (budh->data[pduIndex-1]&0x7f); i++) |
| { |
| //LOGP(DBSSGP, LOGL_NOTICE, "-0x%02x\n", budh ->data[i]); |
| pdu[dataIndex] = budh ->data[i]; |
| dataIndex++; |
| } |
| DEBUGP(DBSSGP, "BSSGP Catch from SGSN=%u octets. Send it to OpenBTS.\n", dataIndex); |
| sendToGSMTAP(pdu,dataIndex); |
| if (dataIndex > BLOCK_DATA_LEN + 1) |
| { |
| int blockDataLen = BLOCK_DATA_LEN; |
| numBlocks = dataIndex/BLOCK_DATA_LEN; |
| int ost = dataIndex%BLOCK_DATA_LEN; |
| int startIndex = 0; |
| int endIndex = 0; |
| if (dataIndex%BLOCK_DATA_LEN > 0) |
| { |
| numBlocks++; |
| } |
| for (i = 0; i < numBlocks; i++) |
| { |
| if (i == numBlocks-1) |
| { |
| if (ost > 0) |
| { |
| blockDataLen = ost; |
| } |
| fbi = 1; |
| } |
| endIndex = startIndex + blockDataLen; |
| sendRLC(ntohl(budh->tlli), pdu, startIndex, endIndex, i, fbi); |
| startIndex += blockDataLen; |
| } |
| } |
| else |
| { |
| sendRLC(ntohl(budh->tlli), pdu, 0, dataIndex, 0, 1); |
| } |
| 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_bss_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_bss_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_bss_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_bss_rx_ptp(msg, &tp, bctx); |
| } |
| return rc; |
| } |
| |
| |
| int sgsn_ns_cb(enum gprs_ns_evt event, struct gprs_nsvc *nsvc, struct msgb *msg, uint16_t bvci) |
| { |
| int rc = 0; |
| switch (event) { |
| case GPRS_NS_EVT_UNIT_DATA: |
| /* hand the message into the BSSGP implementation */ |
| rc = gprs_bssgp_bss_rcvmsg(msg); |
| break; |
| default: |
| LOGP(DGPRS, LOGL_ERROR, "RLCMAC: Unknown event %u from NS\n", event); |
| if (msg) |
| talloc_free(msg); |
| rc = -EIO; |
| break; |
| } |
| return rc; |
| } |
| |
| // Send RLC data to SGSN. |
| void sendToSGSN(uint8_t tfi, uint32_t tlli, uint8_t * rlc_data, unsigned dataLen) |
| { |
| const uint8_t qos_profile = QOS_PROFILE; |
| struct msgb *llc_pdu; |
| unsigned msgLen = NS_HDR_LEN + BSSGP_HDR_LEN + dataLen; |
| TFI = tfi; |
| bctx->cell_id = CELL_ID; |
| bctx->nsei = NSEI; |
| bctx->ra_id.mnc = MNC; |
| bctx->ra_id.mcc = MCC; |
| bctx->ra_id.lac = LAC; |
| bctx->ra_id.rac = RAC; |
| bctx->bvci = BVCI; |
| LOGP(DBSSGP, LOGL_DEBUG, "Data len %u TLLI 0x%08x , TFI 0x%02x", dataLen, tlli, tfi); |
| //for (unsigned i = 0; i < dataLen; i++) |
| // LOGP(DBSSGP, LOGL_DEBUG, " Data[%u] = %u", i, rlc_data[i]); |
| llc_pdu = msgb_alloc_headroom(msgLen, msgLen,"llc_pdu"); |
| msgb_tvlv_push(llc_pdu, BSSGP_IE_LLC_PDU, sizeof(uint8_t)*dataLen, rlc_data); |
| bssgp_tx_ul_ud(bctx, tlli, &qos_profile, llc_pdu); |
| } |
| |
| void RLCMACServer() |
| { |
| uint16_t nsvci = NSVCI; |
| |
| // Socket for reading BitVectors (RLC/MAC Frames) from OpenBTS application. |
| Thread RLCMACInterface; |
| RLCMACInterface.start(RLCMACSocket,NULL); |
| |
| osmo_init_logging(&log_info); |
| sgsn_nsi = gprs_ns_instantiate(&sgsn_ns_cb); |
| bssgp_nsi = sgsn_nsi; |
| |
| if (!bssgp_nsi) |
| { |
| LOGP(DGPRS, LOGL_ERROR, "Unable to instantiate NS\n"); |
| exit(1); |
| } |
| |
| bctx->cell_id = CELL_ID; |
| bctx->nsei = NSEI; |
| bctx->ra_id.mnc = MNC; |
| bctx->ra_id.mcc = MCC; |
| bctx->ra_id.lac = LAC; |
| bctx->ra_id.rac = RAC; |
| bctx->bvci = BVCI; |
| uint8_t cause = 39; |
| gprs_ns_nsip_listen(sgsn_nsi); |
| |
| struct sockaddr_in dest; |
| dest.sin_family = AF_INET; |
| dest.sin_port = htons(SGSN_PORT); |
| inet_aton(SGSN_IP, &dest.sin_addr); |
| |
| nsvc = nsip_connect(sgsn_nsi, &dest, nsei, nsvci); |
| unsigned i = 0; |
| while (1) |
| { |
| osmo_select_main(0); |
| if (i == 7) |
| { |
| bssgp_tx_bvc_reset(bctx, bvci, cause); |
| } |
| i++; |
| } |
| } |