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Diffstat (limited to 'gprs_rlcmac.cpp')
| -rw-r--r-- | gprs_rlcmac.cpp | 527 |
1 files changed, 527 insertions, 0 deletions
diff --git a/gprs_rlcmac.cpp b/gprs_rlcmac.cpp new file mode 100644 index 00000000..c350a7bc --- /dev/null +++ b/gprs_rlcmac.cpp @@ -0,0 +1,527 @@ +/* gprs_rlcmac.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_bssgp_pcu.h> +#include <pcu_l1_if.h> +#include <Threads.h> +#include <gprs_rlcmac.h> + + +LLIST_HEAD(gprs_rlcmac_tbfs); +void *rlcmac_tall_ctx; + +int tfi_alloc() +{ + struct gprs_rlcmac_tbf *tbf; + uint32_t tfi_map = 0; + uint32_t tfi_ind = 0; + uint32_t mask = 1; + uint8_t i; + + llist_for_each_entry(tbf, &gprs_rlcmac_tbfs, list) { + tfi_ind = 1 << tbf->tfi; + tfi_map = tfi_map|tfi_ind; + } + + for (i = 0; i < 32; i++) { + if(((tfi_map >> i) & mask) == 0) { + return i; + } + } + return -1; +} + +/* lookup TBF Entity (by TFI) */ +static struct gprs_rlcmac_tbf *tbf_by_tfi(uint8_t tfi) +{ + struct gprs_rlcmac_tbf *tbf; + + llist_for_each_entry(tbf, &gprs_rlcmac_tbfs, list) { + if (tbf->tfi == tfi) + return tbf; + } + return NULL; +} + +static struct gprs_rlcmac_tbf *tbf_by_tlli(uint8_t tlli) +{ + struct gprs_rlcmac_tbf *tbf; + + llist_for_each_entry(tbf, &gprs_rlcmac_tbfs, list) { + if ((tbf->tlli == tlli)&&(tbf->direction == GPRS_RLCMAC_UL_TBF)) + return tbf; + } + return NULL; +} + +struct gprs_rlcmac_tbf *tbf_alloc(uint8_t tfi) +{ + struct gprs_rlcmac_tbf *tbf; + + tbf = talloc_zero(rlcmac_tall_ctx, struct gprs_rlcmac_tbf); + if (!tbf) + return NULL; + + tbf->tfi = tfi; + + llist_add(&tbf->list, &gprs_rlcmac_tbfs); + + return tbf; +} + +static void tbf_free(struct gprs_rlcmac_tbf *tbf) +{ + llist_del(&tbf->list); + talloc_free(tbf); +} + +void write_packet_downlink_assignment(BitVector * dest, uint8_t tfi, uint32_t tlli) +{ + // TODO We should use our implementation of encode RLC/MAC Control messages. + unsigned wp = 0; + dest->writeField(wp,0x1,2); // Payload Type + dest->writeField(wp,0x0,2); // Uplink block with TDMA framenumber + dest->writeField(wp,0x1,1); // Suppl/Polling Bit + dest->writeField(wp,0x1,3); // Uplink state flag + dest->writeField(wp,0x2,6); // MESSAGE TYPE + dest->writeField(wp,0x0,2); // Page Mode + + dest->writeField(wp,0x0,1); // switch PERSIST_LEVEL: off + dest->writeField(wp,0x2,2); // switch TLLI : on + dest->writeField(wp,tlli,32); // TLLI + + dest->writeField(wp,0x0,1); // Message escape + dest->writeField(wp,0x0,2); // Medium Access Method: Dynamic Allocation + dest->writeField(wp,0x0,1); // RLC acknowledged mode + + dest->writeField(wp,0x0,1); // the network establishes no new downlink TBF for the mobile station + dest->writeField(wp,0x1,8); // timeslot 7 + dest->writeField(wp,0x1,8); // TIMING_ADVANCE_INDEX + + dest->writeField(wp,0x0,1); // switch TIMING_ADVANCE_VALUE = off + dest->writeField(wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on + dest->writeField(wp,0xC,4); // TIMING_ADVANCE_INDEX + dest->writeField(wp,0x7,3); // TIMING_ADVANCE_TIMESLOT_NUMBER + + dest->writeField(wp,0x0,1); // switch POWER CONTROL = off + dest->writeField(wp,0x1,1); // Frequency Parameters information elements = present + + dest->writeField(wp,0x2,3); // Training Sequence Code (TSC) = 2 + dest->writeField(wp,0x1,2); // Indirect encoding struct = present + dest->writeField(wp,0x0,6); // MAIO + dest->writeField(wp,0xE,4); // MA_Number + dest->writeField(wp,0x8,4); // CHANGE_MARK_1 CHANGE_MARK_2 + + dest->writeField(wp,0x1,1); // switch TFI : on + dest->writeField(wp,tfi,5);// TFI + + dest->writeField(wp,0x1,1); // Power Control Parameters IE = present + dest->writeField(wp,0x0,4); // ALPHA power control parameter + dest->writeField(wp,0x0,1); // switch GAMMA_TN0 = off + dest->writeField(wp,0x0,1); // switch GAMMA_TN1 = off + dest->writeField(wp,0x0,1); // switch GAMMA_TN2 = off + dest->writeField(wp,0x0,1); // switch GAMMA_TN3 = off + dest->writeField(wp,0x0,1); // switch GAMMA_TN4 = off + dest->writeField(wp,0x0,1); // switch GAMMA_TN5 = off + dest->writeField(wp,0x0,1); // switch GAMMA_TN6 = off + dest->writeField(wp,0x1,1); // switch GAMMA_TN7 = on + dest->writeField(wp,0x0,5); // GAMMA_TN7 + + dest->writeField(wp,0x0,1); // TBF Starting TIME IE not present + dest->writeField(wp,0x0,1); // Measurement Mapping struct not present +} + +void write_packet_uplink_assignment(BitVector * dest, uint8_t tfi, uint32_t tlli) +{ + // TODO We should use our implementation of encode RLC/MAC Control messages. + unsigned wp = 0; + dest->writeField(wp,0x1,2); // Payload Type + dest->writeField(wp,0x0,2); // Uplink block with TDMA framenumber + dest->writeField(wp,0x1,1); // Suppl/Polling Bit + dest->writeField(wp,0x1,3); // Uplink state flag + + + dest->writeField(wp,0xa,6); // MESSAGE TYPE + + dest->writeField(wp,0x0,2); // Page Mode + + dest->writeField(wp,0x0,1); // switch PERSIST_LEVEL: off + dest->writeField(wp,0x2,2); // switch TLLI : on + dest->writeField(wp,tlli,32); // TLLI + + dest->writeField(wp,0x0,1); // Message escape + dest->writeField(wp,0x0,2); // CHANNEL_CODING_COMMAND + dest->writeField(wp,0x0,1); // TLLI_BLOCK_CHANNEL_CODING + + dest->writeField(wp,0x1,1); // switch TIMING_ADVANCE_VALUE = on + dest->writeField(wp,0x0,6); // TIMING_ADVANCE_VALUE + dest->writeField(wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off + + dest->writeField(wp,0x0,1); // Frequency Parameters = off + + dest->writeField(wp,0x1,2); // Dynamic Allocation = off + + dest->writeField(wp,0x0,1); // Dynamic Allocation + dest->writeField(wp,0x0,1); // P0 = off + + dest->writeField(wp,0x1,1); // USF_GRANULARITY + dest->writeField(wp,0x1,1); // switch TFI : on + dest->writeField(wp,tfi,5);// TFI + + dest->writeField(wp,0x0,1); // + dest->writeField(wp,0x0,1); // TBF Starting Time = off + dest->writeField(wp,0x0,1); // Timeslot Allocation + + dest->writeField(wp,0x0,5); // USF_TN 0 - 4 + dest->writeField(wp,0x1,1); // USF_TN 5 + dest->writeField(wp,0x1,3); // USF_TN 5 + dest->writeField(wp,0x0,2); // USF_TN 6 - 7 +// dest->writeField(wp,0x0,1); // Measurement Mapping struct not present +} + +void write_ia_rest_octets_downlink_assignment(BitVector * dest, uint8_t tfi, uint32_t tlli) +{ + // GMS 04.08 10.5.2.37b 10.5.2.16 + unsigned wp = 0; + dest->writeField(wp, 3, 2); // "HH" + dest->writeField(wp, 1, 2); // "01" Packet Downlink Assignment + dest->writeField(wp,tlli,32); // TLLI + dest->writeField(wp,0x1,1); // switch TFI : on + dest->writeField(wp,tfi,5); // TFI + dest->writeField(wp,0x0,1); // RLC acknowledged mode + dest->writeField(wp,0x0,1); // ALPHA = present + //dest->writeField(wp,0x0,4); // ALPHA power control parameter + dest->writeField(wp,0x0,5); // GAMMA power control parameter + dest->writeField(wp,0x1,1); // Polling Bit + dest->writeField(wp,0x1,1); // TA_VALID ??? + dest->writeField(wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on + dest->writeField(wp,0xC,4); // TIMING_ADVANCE_INDEX + dest->writeField(wp,0x1,1); // TBF Starting TIME present + dest->writeField(wp,0xffff,16); // TBF Starting TIME (we should set it in OpenBTS) + dest->writeField(wp,0x0,1); // P0 not present +} + +void write_packet_uplink_ack(BitVector * dest, uint8_t tfi, uint32_t tlli, unsigned cv, unsigned bsn) +{ + // TODO We should use our implementation of encode RLC/MAC Control messages. + unsigned wp = 0; + dest->writeField(wp,0x1,2); // payload + dest->writeField(wp,0x0,2); // Uplink block with TDMA framenumber + if (cv == 0) dest->writeField(wp,0x1,1); // Suppl/Polling Bit + else dest->writeField(wp,0x0,1); //Suppl/Polling Bit + dest->writeField(wp,0x1,3); // Uplink state flag + + //dest->writeField(wp,0x0,1); // Reduced block sequence number + //dest->writeField(wp,BSN+6,5); // Radio transaction identifier + //dest->writeField(wp,0x1,1); // Final segment + //dest->writeField(wp,0x1,1); // Address control + + //dest->writeField(wp,0x0,2); // Power reduction: 0 + //dest->writeField(wp,TFI,5); // Temporary flow identifier + //dest->writeField(wp,0x1,1); // Direction + + dest->writeField(wp,0x09,6); // MESSAGE TYPE + dest->writeField(wp,0x0,2); // Page Mode + + dest->writeField(wp,0x0,2); + dest->writeField(wp,tfi,5); // Uplink TFI + dest->writeField(wp,0x0,1); + + dest->writeField(wp,0x0,2); // CS1 + if (cv == 0) dest->writeField(wp,0x1,1); // FINAL_ACK_INDICATION + else dest->writeField(wp,0x0,1); // FINAL_ACK_INDICATION + dest->writeField(wp,bsn + 1,7); // STARTING_SEQUENCE_NUMBER + // RECEIVE_BLOCK_BITMAP + for (unsigned i=0; i<8; i++) { + dest->writeField(wp,0xff,8); + } + dest->writeField(wp,0x1,1); // CONTENTION_RESOLUTION_TLLI = present + dest->writeField(wp,tlli,8*4); + dest->writeField(wp,0x00,4); //spare +} + +void gprs_rlcmac_tx_ul_ack(uint8_t tfi, uint32_t tlli, RlcMacUplinkDataBlock_t * ul_data_block) +{ + BitVector packet_uplink_ack_vec(23*8); + packet_uplink_ack_vec.unhex("2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); + write_packet_uplink_ack(&packet_uplink_ack_vec, tfi, tlli, ul_data_block->CV, ul_data_block->BSN); + COUT("RLCMAC_CONTROL_BLOCK>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>"); + RlcMacDownlink_t * packet_uplink_ack = (RlcMacDownlink_t *)malloc(sizeof(RlcMacUplink_t)); + decode_gsm_rlcmac_downlink(&packet_uplink_ack_vec, packet_uplink_ack); + free(packet_uplink_ack); + COUT("RLCMAC_CONTROL_BLOCK_END------------------------------"); + pcu_l1if_tx(&packet_uplink_ack_vec); +} + +void gprs_rlcmac_data_block_parse(gprs_rlcmac_tbf* tbf, RlcMacUplinkDataBlock_t * ul_data_block) +{ + unsigned block_data_len = 0; + unsigned data_octet_num = 0; + + if (ul_data_block->E_1 == 0) // Extension octet follows immediately + { + // TODO We should implement case with several LLC PDU in one data block. + block_data_len = ul_data_block->LENGTH_INDICATOR[0]; + } + else + { + block_data_len = 20; // RLC data length without 3 header octets. + if(ul_data_block->TI == 1) // TLLI field is present + { + tbf->tlli = ul_data_block->TLLI; + block_data_len -= 4; // TLLI length + if (ul_data_block->PI == 1) // PFI is present if TI field indicates presence of TLLI + { + block_data_len -= 1; // PFI length + } + } + } + + for (unsigned i = tbf->data_index; i < tbf->data_index + block_data_len; i++) + { + tbf->rlc_data[i] = ul_data_block->RLC_DATA[data_octet_num]; + data_octet_num++; + } + tbf->data_index += block_data_len; +} + +/* Received Uplink RLC data block. */ +int gprs_rlcmac_rcv_data_block(BitVector *rlc_block) +{ + struct gprs_rlcmac_tbf *tbf; + + COUT("RLCMAC_DATA_BLOCK<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<"); + RlcMacUplinkDataBlock_t * ul_data_block = (RlcMacUplinkDataBlock_t *)malloc(sizeof(RlcMacUplinkDataBlock_t)); + decode_gsm_rlcmac_uplink_data(rlc_block, ul_data_block); + COUT("RLCMAC_DATA_BLOCK_END------------------------------"); + + tbf = tbf_by_tfi(ul_data_block->TFI); + if (!tbf) { + tbf = tbf_alloc(ul_data_block->TFI); + if (tbf) { + tbf->direction = GPRS_RLCMAC_UL_TBF; + tbf->state = GPRS_RLCMAC_WAIT_DATA_SEQ_START; + } else { + return 0; + } + } + + switch (tbf->state) { + case GPRS_RLCMAC_WAIT_DATA_SEQ_START: + if (ul_data_block->BSN == 0) { + tbf->data_index = 0; + gprs_rlcmac_data_block_parse(tbf, ul_data_block); + gprs_rlcmac_tx_ul_ack(tbf->tfi, tbf->tlli, ul_data_block); + tbf->state = GPRS_RLCMAC_WAIT_NEXT_DATA_BLOCK; + tbf->bsn = ul_data_block->BSN; + } + break; + case GPRS_RLCMAC_WAIT_NEXT_DATA_BLOCK: + if (tbf->bsn == (ul_data_block->BSN - 1)) { + gprs_rlcmac_data_block_parse(tbf, ul_data_block); + gprs_rlcmac_tx_ul_ack(tbf->tfi, tbf->tlli, ul_data_block); + if (ul_data_block->CV == 0) { + // Recieved last Data Block in this sequence. + gsmtap_send_llc(tbf->rlc_data, tbf->data_index); + tbf->state = GPRS_RLCMAC_WAIT_NEXT_DATA_SEQ; + } else { + tbf->bsn = ul_data_block->BSN; + tbf->state = GPRS_RLCMAC_WAIT_NEXT_DATA_BLOCK; + } + } else { + // Recieved Data Block with unexpected BSN. + // We should try to find nesessary Data Block. + tbf->state = GPRS_RLCMAC_WAIT_NEXT_DATA_BLOCK; + } + break; + case GPRS_RLCMAC_WAIT_NEXT_DATA_SEQ: + // Now we just ignore all Data Blocks and wait next Uplink TBF + break; + } + + free(ul_data_block); + return 1; +} + +/* Received Uplink RLC control block. */ +int gprs_rlcmac_rcv_control_block(BitVector *rlc_block) +{ + //static unsigned shutUp = 0; + uint8_t tfi = 0; + uint32_t tlli = 0; + struct gprs_rlcmac_tbf *tbf; + + COUT("RLCMAC_CONTROL_BLOCK<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<"); + RlcMacUplink_t * ul_control_block = (RlcMacUplink_t *)malloc(sizeof(RlcMacUplink_t)); + decode_gsm_rlcmac_uplink(rlc_block, ul_control_block); + COUT("RLCMAC_CONTROL_BLOCK_END------------------------------"); + + //gprs_rlcmac_control_block_get_tfi_tlli(ul_control_block, &tfi, &tlli); + tbf = tbf_by_tfi(tfi); + if (!tbf) { + return 0; + } + + switch (ul_control_block->u.MESSAGE_TYPE) { + case MT_PACKET_CONTROL_ACK: + /* + COUT("SEND IA Rest Octets Downlink Assignment>>>>>>>>>>>>>>>>>>"); + BitVector IARestOctetsDownlinkAssignment(23*8); + IARestOctetsDownlinkAssignment.unhex("2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); + writeIARestOctetsDownlinkAssignment(&IARestOctetsDownlinkAssignment, 20, *tlli); + sendToOpenBTS(&IARestOctetsDownlinkAssignment); + */ + //usleep(500000); + tlli = ul_control_block->u.Packet_Control_Acknowledgement.TLLI; + tbf = tbf_by_tlli(tlli); + if (!tbf) { + return 0; + } + gprs_rlcmac_tx_ul_ud(tbf); + tbf_free(tbf); + break; + case MT_PACKET_DOWNLINK_ACK_NACK: + tfi = ul_control_block->u.Packet_Downlink_Ack_Nack.DOWNLINK_TFI; + tbf = tbf_by_tfi(tfi); + if (!tbf) { + return 0; + } + //COUT("SEND PacketUplinkAssignment>>>>>>>>>>>>>>>>>>"); + //BitVector PacketUplinkAssignment(23*8); + //PacketUplinkAssignment.unhex("2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); + //writePUassignment(&PacketUplinkAssignment, tbf->tfi, tbf->tlli); + //sendToOpenBTS(&PacketUplinkAssignment); + break; + } + free(ul_control_block); + return 1; +} + +void gprs_rlcmac_rcv_block(BitVector *rlc_block) +{ + unsigned readIndex = 0; + unsigned payload = rlc_block->readField(readIndex, 2); + + switch (payload) { + case GPRS_RLCMAC_DATA_BLOCK: + gprs_rlcmac_rcv_data_block(rlc_block); + break; + case GPRS_RLCMAC_CONTROL_BLOCK: + gprs_rlcmac_rcv_control_block(rlc_block); + break; + case GPRS_RLCMAC_CONTROL_BLOCK_OPT: + COUT("GPRS_RLCMAC_CONTROL_BLOCK_OPT block payload is not supported.\n"); + default: + COUT("Unknown RLCMAC block payload.\n"); + } +} + +// Send RLC data to OpenBTS. +void gprs_rlcmac_tx_dl_data_block(uint32_t tlli, uint8_t *pdu, int start_index, int end_index, uint8_t bsn, uint8_t fbi) +{ + int spare_len = 0; + BitVector data_block_vector(BLOCK_LEN*8); + data_block_vector.unhex("2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); + RlcMacDownlinkDataBlock_t * data_block = (RlcMacDownlinkDataBlock_t *)malloc(sizeof(RlcMacDownlinkDataBlock_t)); + data_block->PAYLOAD_TYPE = 0; + data_block->RRBP = 0; + data_block->SP = 1; + data_block->USF = 1; + data_block->PR = 0; + data_block->TFI = 20; + data_block->FBI = fbi; + data_block->BSN = bsn; + if ((end_index - start_index) < 20) { + data_block->E_1 = 0; + data_block->LENGTH_INDICATOR[0] = end_index-start_index; + data_block->M[0] = 0; + data_block->E[0] = 1; + spare_len = 19 - data_block->LENGTH_INDICATOR[0]; + } else { + data_block->E_1 = 1; + } + int j = 0; + int i = 0; + for(i = start_index; i < end_index; i++) { + data_block->RLC_DATA[j] = pdu[i]; + j++; + } + + for(i = j; i < j + spare_len; i++) { + data_block->RLC_DATA[i] = 0x2b; + } + encode_gsm_rlcmac_downlink_data(&data_block_vector, data_block); + free(data_block); + pcu_l1if_tx(&data_block_vector); +} + +int gprs_rlcmac_segment_llc_pdu(struct gprs_rlcmac_tbf *tbf) +{ + int fbi = 0; + int num_blocks = 0; + int i; + + if (tbf->data_index > BLOCK_DATA_LEN + 1) + { + int block_data_len = BLOCK_DATA_LEN; + num_blocks = tbf->data_index/BLOCK_DATA_LEN; + int rest_len = tbf->data_index%BLOCK_DATA_LEN; + int start_index = 0; + int end_index = 0; + if (tbf->data_index%BLOCK_DATA_LEN > 0) + { + num_blocks++; + } + for (i = 0; i < num_blocks; i++) + { + if (i == num_blocks-1) + { + if (rest_len > 0) + { + block_data_len = rest_len; + } + fbi = 1; + } + end_index = start_index + block_data_len; + gprs_rlcmac_tx_dl_data_block(tbf->tlli, tbf->rlc_data, start_index, end_index, i, fbi); + start_index += block_data_len; + } + } + else + { + gprs_rlcmac_tx_dl_data_block(tbf->tlli, tbf->rlc_data, 0, tbf->data_index, 0, 1); + } +} + +/* Send Uplink unit-data to SGSN. */ +void gprs_rlcmac_tx_ul_ud(gprs_rlcmac_tbf *tbf) +{ + const uint8_t qos_profile = QOS_PROFILE; + struct msgb *llc_pdu; + unsigned msg_len = NS_HDR_LEN + BSSGP_HDR_LEN + tbf->data_index; + + LOGP(DBSSGP, LOGL_DEBUG, "Data len %u TLLI 0x%08x , TFI 0x%02x", tbf->data_index, tbf->tlli, tbf->tfi); + //for (unsigned i = 0; i < dataLen; i++) + // LOGP(DBSSGP, LOGL_DEBUG, " Data[%u] = %u", i, rlc_data[i]); + + llc_pdu = msgb_alloc_headroom(msg_len, msg_len,"llc_pdu"); + msgb_tvlv_push(llc_pdu, BSSGP_IE_LLC_PDU, sizeof(uint8_t)*tbf->data_index, tbf->rlc_data); + bssgp_tx_ul_ud(bctx, tbf->tlli, &qos_profile, llc_pdu); +} + |