| /* 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> |
| #include <gsmL1prim.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(uint32_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); |
| } |
| |
| |
| static void tbf_timer_cb(void *_tbf) |
| { |
| struct gprs_rlcmac_tbf *tbf = (struct gprs_rlcmac_tbf *)_tbf; |
| |
| tbf->num_T_exp++; |
| |
| switch (tbf->T) { |
| case 1111: |
| // TODO: We should add timers for TBF. |
| break; |
| default: |
| COUT("Timer expired in unknown mode" << tbf->T); |
| } |
| } |
| |
| static void tbf_timer_start(struct gprs_rlcmac_tbf *tbf, unsigned int T, |
| unsigned int seconds) |
| { |
| if (osmo_timer_pending(&tbf->timer)) |
| COUT("Starting TBF timer %u while old timer %u pending" << T << tbf->T); |
| tbf->T = T; |
| tbf->num_T_exp = 0; |
| |
| /* FIXME: we should do this only once ? */ |
| tbf->timer.data = tbf; |
| tbf->timer.cb = &tbf_timer_cb; |
| |
| osmo_timer_schedule(&tbf->timer, seconds, 0); |
| } |
| |
| |
| static void tbf_gsm_timer_cb(void *_tbf) |
| { |
| struct gprs_rlcmac_tbf *tbf = (struct gprs_rlcmac_tbf *)_tbf; |
| |
| tbf->num_fT_exp++; |
| |
| switch (tbf->fT) { |
| case 0: |
| // This is timer for delay RLC/MAC data sending after Downlink Immediate Assignment on CCCH. |
| gprs_rlcmac_segment_llc_pdu(tbf); |
| LOGP(DRLCMAC, LOGL_NOTICE, "TBF: [DOWNLINK] END TFI: %u TLLI: 0x%08x \n", tbf->tfi, tbf->tlli); |
| tbf_free(tbf); |
| break; |
| default: |
| COUT("Timer expired in unknown mode" << tbf->fT); |
| } |
| } |
| |
| static void tbf_gsm_timer_start(struct gprs_rlcmac_tbf *tbf, unsigned int fT, |
| int frames) |
| { |
| if (osmo_gsm_timer_pending(&tbf->gsm_timer)) |
| COUT("Starting TBF timer %u while old timer %u pending" << fT << tbf->fT); |
| tbf->fT = fT; |
| tbf->num_fT_exp = 0; |
| |
| /* FIXME: we should do this only once ? */ |
| tbf->gsm_timer.data = tbf; |
| tbf->gsm_timer.cb = &tbf_gsm_timer_cb; |
| |
| osmo_gsm_timer_schedule(&tbf->gsm_timer, frames); |
| } |
| |
| void write_packet_downlink_assignment(bitvec * dest, uint8_t tfi, uint32_t tlli, uint8_t tn, uint8_t ta, uint8_t tsc) |
| { |
| // TODO We should use our implementation of encode RLC/MAC Control messages. |
| unsigned wp = 0; |
| bitvec_write_field(dest, wp,0x1,2); // Payload Type |
| bitvec_write_field(dest, wp,0x0,2); // Uplink block with TDMA framenumber |
| bitvec_write_field(dest, wp,0x1,1); // Suppl/Polling Bit |
| bitvec_write_field(dest, wp,0x1,3); // Uplink state flag |
| bitvec_write_field(dest, wp,0x2,6); // MESSAGE TYPE |
| bitvec_write_field(dest, wp,0x0,2); // Page Mode |
| |
| bitvec_write_field(dest, wp,0x0,1); // switch PERSIST_LEVEL: off |
| bitvec_write_field(dest, wp,0x0,1); // switch TFI : on |
| bitvec_write_field(dest, wp,0x0,1); // switch UPLINK TFI : on |
| bitvec_write_field(dest, wp,tfi-1,5); // TFI |
| |
| bitvec_write_field(dest, wp,0x0,1); // Message escape |
| bitvec_write_field(dest, wp,0x0,2); // Medium Access Method: Dynamic Allocation |
| bitvec_write_field(dest, wp,0x0,1); // RLC acknowledged mode |
| |
| bitvec_write_field(dest, wp,0x0,1); // the network establishes no new downlink TBF for the mobile station |
| bitvec_write_field(dest, wp,0x1,8); // timeslot 7 |
| |
| bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_VALUE = on |
| bitvec_write_field(dest, wp,ta,6); // TIMING_ADVANCE_VALUE |
| bitvec_write_field(dest, wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off |
| |
| bitvec_write_field(dest, wp,0x0,1); // switch POWER CONTROL = off |
| bitvec_write_field(dest, wp,0x1,1); // Frequency Parameters information elements = present |
| |
| bitvec_write_field(dest, wp,tsc,3); // Training Sequence Code (TSC) = 2 |
| bitvec_write_field(dest, wp,0x0,2); // ARFCN = present |
| bitvec_write_field(dest, wp,599,10); // ARFCN |
| |
| bitvec_write_field(dest, wp,0x1,1); // switch TFI : on |
| bitvec_write_field(dest, wp,tfi,5);// TFI |
| |
| bitvec_write_field(dest, wp,0x1,1); // Power Control Parameters IE = present |
| bitvec_write_field(dest, wp,0x0,4); // ALPHA power control parameter |
| bitvec_write_field(dest, wp,0x0,1); // switch GAMMA_TN0 = off |
| bitvec_write_field(dest, wp,0x0,1); // switch GAMMA_TN1 = off |
| bitvec_write_field(dest, wp,0x0,1); // switch GAMMA_TN2 = off |
| bitvec_write_field(dest, wp,0x0,1); // switch GAMMA_TN3 = off |
| bitvec_write_field(dest, wp,0x0,1); // switch GAMMA_TN4 = off |
| bitvec_write_field(dest, wp,0x0,1); // switch GAMMA_TN5 = off |
| bitvec_write_field(dest, wp,0x0,1); // switch GAMMA_TN6 = off |
| bitvec_write_field(dest, wp,0x1,1); // switch GAMMA_TN7 = on |
| bitvec_write_field(dest, wp,0x0,5); // GAMMA_TN7 |
| |
| bitvec_write_field(dest, wp,0x0,1); // TBF Starting TIME IE not present |
| bitvec_write_field(dest, wp,0x0,1); // Measurement Mapping struct not present |
| bitvec_write_field(dest, wp,0x0,1); |
| } |
| |
| void write_packet_uplink_assignment(bitvec * dest, uint8_t tfi, uint32_t tlli) |
| { |
| // TODO We should use our implementation of encode RLC/MAC Control messages. |
| unsigned wp = 0; |
| bitvec_write_field(dest, wp,0x1,2); // Payload Type |
| bitvec_write_field(dest, wp,0x0,2); // Uplink block with TDMA framenumber |
| bitvec_write_field(dest, wp,0x1,1); // Suppl/Polling Bit |
| bitvec_write_field(dest, wp,0x1,3); // Uplink state flag |
| |
| |
| bitvec_write_field(dest, wp,0xa,6); // MESSAGE TYPE |
| |
| bitvec_write_field(dest, wp,0x0,2); // Page Mode |
| |
| bitvec_write_field(dest, wp,0x0,1); // switch PERSIST_LEVEL: off |
| bitvec_write_field(dest, wp,0x2,2); // switch TLLI : on |
| bitvec_write_field(dest, wp,tlli,32); // TLLI |
| |
| bitvec_write_field(dest, wp,0x0,1); // Message escape |
| bitvec_write_field(dest, wp,0x0,2); // CHANNEL_CODING_COMMAND |
| bitvec_write_field(dest, wp,0x0,1); // TLLI_BLOCK_CHANNEL_CODING |
| |
| bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_VALUE = on |
| bitvec_write_field(dest, wp,0x0,6); // TIMING_ADVANCE_VALUE |
| bitvec_write_field(dest, wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off |
| |
| bitvec_write_field(dest, wp,0x0,1); // Frequency Parameters = off |
| |
| bitvec_write_field(dest, wp,0x1,2); // Dynamic Allocation = off |
| |
| bitvec_write_field(dest, wp,0x0,1); // Dynamic Allocation |
| bitvec_write_field(dest, wp,0x0,1); // P0 = off |
| |
| bitvec_write_field(dest, wp,0x1,1); // USF_GRANULARITY |
| bitvec_write_field(dest, wp,0x1,1); // switch TFI : on |
| bitvec_write_field(dest, wp,tfi,5);// TFI |
| |
| bitvec_write_field(dest, wp,0x0,1); // |
| bitvec_write_field(dest, wp,0x0,1); // TBF Starting Time = off |
| bitvec_write_field(dest, wp,0x0,1); // Timeslot Allocation |
| |
| bitvec_write_field(dest, wp,0x0,5); // USF_TN 0 - 4 |
| bitvec_write_field(dest, wp,0x1,1); // USF_TN 5 |
| bitvec_write_field(dest, wp,0x1,3); // USF_TN 5 |
| bitvec_write_field(dest, wp,0x0,2); // USF_TN 6 - 7 |
| // bitvec_write_field(dest, wp,0x0,1); // Measurement Mapping struct not present |
| } |
| |
| |
| // GSM 04.08 9.1.18 Immediate assignment |
| int write_immediate_assignment(bitvec * dest, uint8_t downlink, uint8_t ra, uint32_t fn, |
| uint8_t ta, uint8_t tfi = 0, uint32_t tlli = 0) |
| { |
| unsigned wp = 0; |
| |
| bitvec_write_field(dest, wp,0x0,4); // Skip Indicator |
| bitvec_write_field(dest, wp,0x6,4); // Protocol Discriminator |
| bitvec_write_field(dest, wp,0x3F,8); // Immediate Assignment Message Type |
| |
| // 10.5.2.25b Dedicated mode or TBF |
| bitvec_write_field(dest, wp,0x0,1); // spare |
| bitvec_write_field(dest, wp,0x0,1); // TMA : Two-message assignment: No meaning |
| bitvec_write_field(dest, wp,downlink,1); // Downlink : Downlink assignment to mobile in packet idle mode |
| bitvec_write_field(dest, wp,0x1,1); // T/D : TBF or dedicated mode: this message assigns a Temporary Block Flow (TBF). |
| |
| bitvec_write_field(dest, wp,0x0,4); // Page Mode |
| |
| // GSM 04.08 10.5.2.25a Packet Channel Description |
| bitvec_write_field(dest, wp,0x1,5); // Channel type |
| bitvec_write_field(dest, wp,(l1fh->fl1h)->channel_info.tn,3); // TN |
| bitvec_write_field(dest, wp,(l1fh->fl1h)->channel_info.tsc,3); // TSC |
| bitvec_write_field(dest, wp,0x0,3); // non-hopping RF channel configuraion |
| bitvec_write_field(dest, wp,(l1fh->fl1h)->channel_info.arfcn,10); // ARFCN |
| |
| //10.5.2.30 Request Reference |
| bitvec_write_field(dest, wp,ra,8); // RA |
| bitvec_write_field(dest, wp,(fn / (26 * 51)) % 32,5); // T1' |
| bitvec_write_field(dest, wp,fn % 51,6); // T3 |
| bitvec_write_field(dest, wp,fn % 26,5); // T2 |
| |
| // 10.5.2.40 Timing Advance |
| bitvec_write_field(dest, wp,0x0,2); // spare |
| bitvec_write_field(dest, wp,ta,6); // Timing Advance value |
| |
| // No mobile allocation in non-hopping systems. |
| // A zero-length LV. Just write L=0. |
| bitvec_write_field(dest, wp,0,8); |
| |
| if (downlink) |
| { |
| // GSM 04.08 10.5.2.16 IA Rest Octets |
| bitvec_write_field(dest, wp, 3, 2); // "HH" |
| bitvec_write_field(dest, wp, 1, 2); // "01" Packet Downlink Assignment |
| bitvec_write_field(dest, wp,tlli,32); // TLLI |
| bitvec_write_field(dest, wp,0x1,1); // switch TFI : on |
| bitvec_write_field(dest, wp,tfi,5); // TFI |
| bitvec_write_field(dest, wp,0x0,1); // RLC acknowledged mode |
| bitvec_write_field(dest, wp,0x0,1); // ALPHA = present |
| bitvec_write_field(dest, wp,0x0,5); // GAMMA power control parameter |
| bitvec_write_field(dest, wp,0x0,1); // Polling Bit |
| bitvec_write_field(dest, wp,0x1,1); // TA_VALID ??? |
| bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on |
| bitvec_write_field(dest, wp,0x0,4); // TIMING_ADVANCE_INDEX |
| bitvec_write_field(dest, wp,0x0,1); // TBF Starting TIME present |
| bitvec_write_field(dest, wp,0x0,1); // P0 not present |
| bitvec_write_field(dest, wp,0x1,1); // P0 not present |
| bitvec_write_field(dest, wp,0xb,4); |
| } |
| else |
| { |
| // GMS 04.08 10.5.2.37b 10.5.2.16 |
| bitvec_write_field(dest, wp, 3, 2); // "HH" |
| bitvec_write_field(dest, wp, 0, 2); // "0" Packet Uplink Assignment |
| bitvec_write_field(dest, wp, 1, 1); // Block Allocation : Not Single Block Allocation |
| bitvec_write_field(dest, wp, tfi, 5); // TFI_ASSIGNMENT Temporary Flow Identity |
| bitvec_write_field(dest, wp, 0, 1); // POLLING |
| bitvec_write_field(dest, wp, 0, 1); // ALLOCATION_TYPE: dynamic |
| bitvec_write_field(dest, wp, 1, 3); // USF |
| bitvec_write_field(dest, wp, 1, 1); // USF_GRANULARITY |
| bitvec_write_field(dest, wp, 0 , 1); // "0" power control: Not Present |
| bitvec_write_field(dest, wp, 0, 2); // CHANNEL_CODING_COMMAND |
| bitvec_write_field(dest, wp, 1, 1); // TLLI_BLOCK_CHANNEL_CODING |
| bitvec_write_field(dest, wp, 1 , 1); // "1" Alpha : Present |
| bitvec_write_field(dest, wp, 0, 4); // Alpha |
| bitvec_write_field(dest, wp, 0, 5); // Gamma |
| bitvec_write_field(dest, wp, 0, 1); // TIMING_ADVANCE_INDEX_FLAG |
| bitvec_write_field(dest, wp, 0, 1); // TBF_STARTING_TIME_FLAG |
| } |
| |
| if (wp%8) |
| return wp/8+1; |
| else |
| return wp/8; |
| } |
| |
| |
| void write_ia_rest_octets_downlink_assignment(bitvec * dest, uint8_t tfi, uint32_t tlli) |
| { |
| // GSM 04.08 10.5.2.16 |
| unsigned wp = 0; |
| bitvec_write_field(dest, wp, 3, 2); // "HH" |
| bitvec_write_field(dest, wp, 1, 2); // "01" Packet Downlink Assignment |
| bitvec_write_field(dest, wp,tlli,32); // TLLI |
| bitvec_write_field(dest, wp,0x1,1); // switch TFI : on |
| bitvec_write_field(dest, wp,tfi,5); // TFI |
| bitvec_write_field(dest, wp,0x0,1); // RLC acknowledged mode |
| bitvec_write_field(dest, wp,0x0,1); // ALPHA = present |
| bitvec_write_field(dest, wp,0x0,5); // GAMMA power control parameter |
| bitvec_write_field(dest, wp,0x0,1); // Polling Bit |
| bitvec_write_field(dest, wp,0x1,1); // TA_VALID ??? |
| bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on |
| bitvec_write_field(dest, wp,0x0,4); // TIMING_ADVANCE_INDEX |
| bitvec_write_field(dest, wp,0x0,1); // TBF Starting TIME present |
| bitvec_write_field(dest, wp,0x0,1); // P0 not present |
| bitvec_write_field(dest, wp,0x1,1); // P0 not present |
| bitvec_write_field(dest, wp,0xb,4); |
| } |
| |
| void write_packet_uplink_ack(bitvec * 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; |
| bitvec_write_field(dest, wp,0x1,2); // payload |
| bitvec_write_field(dest, wp,0x0,2); // Uplink block with TDMA framenumber |
| if (cv == 0) bitvec_write_field(dest, wp,0x1,1); // Suppl/Polling Bit |
| else bitvec_write_field(dest, wp,0x0,1); //Suppl/Polling Bit |
| bitvec_write_field(dest, wp,0x1,3); // Uplink state flag |
| |
| //bitvec_write_field(dest, wp,0x0,1); // Reduced block sequence number |
| //bitvec_write_field(dest, wp,BSN+6,5); // Radio transaction identifier |
| //bitvec_write_field(dest, wp,0x1,1); // Final segment |
| //bitvec_write_field(dest, wp,0x1,1); // Address control |
| |
| //bitvec_write_field(dest, wp,0x0,2); // Power reduction: 0 |
| //bitvec_write_field(dest, wp,TFI,5); // Temporary flow identifier |
| //bitvec_write_field(dest, wp,0x1,1); // Direction |
| |
| bitvec_write_field(dest, wp,0x09,6); // MESSAGE TYPE |
| bitvec_write_field(dest, wp,0x0,2); // Page Mode |
| |
| bitvec_write_field(dest, wp,0x0,2); |
| bitvec_write_field(dest, wp,tfi,5); // Uplink TFI |
| bitvec_write_field(dest, wp,0x0,1); |
| |
| bitvec_write_field(dest, wp,0x0,2); // CS1 |
| if (cv == 0) bitvec_write_field(dest, wp,0x1,1); // FINAL_ACK_INDICATION |
| else bitvec_write_field(dest, wp,0x0,1); // FINAL_ACK_INDICATION |
| bitvec_write_field(dest, wp,bsn + 1,7); // STARTING_SEQUENCE_NUMBER |
| // RECEIVE_BLOCK_BITMAP |
| for (unsigned i=0; i<8; i++) { |
| bitvec_write_field(dest, wp,0xff,8); |
| } |
| bitvec_write_field(dest, wp,0x1,1); // CONTENTION_RESOLUTION_TLLI = present |
| bitvec_write_field(dest, wp,tlli,8*4); |
| bitvec_write_field(dest, wp,0x00,4); //spare |
| bitvec_write_field(dest, wp,0x5,4); //0101 |
| } |
| |
| void gprs_rlcmac_tx_ul_ack(uint8_t tfi, uint32_t tlli, RlcMacUplinkDataBlock_t * ul_data_block) |
| { |
| bitvec *packet_uplink_ack_vec = bitvec_alloc(23); |
| bitvec_unhex(packet_uplink_ack_vec, "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); |
| write_packet_uplink_ack(packet_uplink_ack_vec, tfi, tlli, ul_data_block->CV, ul_data_block->BSN); |
| LOGP(DRLCMAC, LOGL_NOTICE, "TX: [PCU -> BTS] TFI: %u TLLI: 0x%08x Packet Uplink Ack\n", tfi, tlli); |
| RlcMacDownlink_t * packet_uplink_ack = (RlcMacDownlink_t *)malloc(sizeof(RlcMacDownlink_t)); |
| LOGP(DRLCMAC, LOGL_NOTICE, "+++++++++++++++++++++++++ TX : Packet Uplink Ack +++++++++++++++++++++++++\n"); |
| decode_gsm_rlcmac_downlink(packet_uplink_ack_vec, packet_uplink_ack); |
| LOGPC(DRLCMAC, LOGL_NOTICE, "\n"); |
| LOGP(DRLCMAC, LOGL_NOTICE, "------------------------- TX : Packet Uplink Ack -------------------------\n"); |
| free(packet_uplink_ack); |
| pcu_l1if_tx(packet_uplink_ack_vec, GsmL1_Sapi_Pacch); |
| bitvec_free(packet_uplink_ack_vec); |
| } |
| |
| void gprs_rlcmac_data_block_parse(gprs_rlcmac_tbf* tbf, RlcMacUplinkDataBlock_t * ul_data_block) |
| { |
| // 1. Count the number of octets in header and number of LLC PDU in uplink data block. |
| unsigned data_block_hdr_len = 3; // uplink data block header length: 3 mandatory octets |
| unsigned llc_pdu_num = 0; // number of LLC PDU in data block |
| |
| |
| if (ul_data_block->E_1 == 0) // Extension octet follows immediately |
| { |
| unsigned i = -1; |
| do |
| { |
| i++; |
| data_block_hdr_len += 1; |
| llc_pdu_num++; |
| |
| // Singular case, TS 44.060 10.4.14 |
| if (ul_data_block->LENGTH_INDICATOR[i] == 0) |
| { |
| break; |
| } |
| |
| // New LLC PDU starts after the current LLC PDU and continues until |
| // the end of the RLC information field, no more extension octets. |
| if ((ul_data_block->M[i] == 1)&&(ul_data_block->E[i] == 1)) |
| { |
| llc_pdu_num++; |
| } |
| } while(ul_data_block->E[i] == 0); // there is another extension octet, which delimits the new LLC PDU |
| } |
| else |
| { |
| llc_pdu_num++; |
| } |
| if(ul_data_block->TI == 1) // TLLI field is present |
| { |
| tbf->tlli = ul_data_block->TLLI; |
| data_block_hdr_len += 4; // TLLI length : 4 octets |
| if (ul_data_block->PI == 1) // PFI is present if TI field indicates presence of TLLI |
| { |
| data_block_hdr_len += 1; // PFI length : 1 octet |
| } |
| } |
| |
| // 2. Extract all LLC PDU from uplink data block and send them to SGSN. |
| unsigned llc_pdu_len = 0; |
| unsigned data_octet_num = 0; |
| |
| for (unsigned num = 0; num < llc_pdu_num; num ++) |
| { |
| if (ul_data_block->E_1 == 0) // Extension octet follows immediately |
| { |
| // Singular case, TS 44.060 10.4.14 |
| if (ul_data_block->LENGTH_INDICATOR[num] == 0) |
| { |
| llc_pdu_len = UL_RLC_DATA_BLOCK_LEN - data_block_hdr_len; |
| } |
| else |
| { |
| llc_pdu_len = ul_data_block->LENGTH_INDICATOR[num]; |
| } |
| } |
| else |
| { |
| llc_pdu_len = UL_RLC_DATA_BLOCK_LEN - data_block_hdr_len; |
| } |
| |
| for (unsigned i = tbf->data_index; i < tbf->data_index + llc_pdu_len; i++) |
| { |
| tbf->rlc_data[i] = ul_data_block->RLC_DATA[data_octet_num]; |
| data_octet_num++; |
| } |
| tbf->data_index += llc_pdu_len; |
| |
| if (ul_data_block->E_1 == 0) // Extension octet follows immediately |
| { |
| // New LLC PDU starts after the current LLC PDU |
| if (ul_data_block->M[num] == 1) |
| { |
| gsmtap_send_llc(tbf->rlc_data, tbf->data_index); |
| gprs_rlcmac_tx_ul_ud(tbf); |
| tbf->data_index = 0; |
| // New LLC PDU continues until the end of the RLC information field, no more extension octets. |
| if ((ul_data_block->E[num] == 1)) |
| { |
| llc_pdu_len = UL_RLC_DATA_BLOCK_LEN - data_block_hdr_len - data_octet_num; |
| for (unsigned i = tbf->data_index; i < tbf->data_index + llc_pdu_len; i++) |
| { |
| tbf->rlc_data[i] = ul_data_block->RLC_DATA[data_octet_num]; |
| data_octet_num++; |
| } |
| tbf->data_index += llc_pdu_len; |
| num++; |
| } |
| } |
| } |
| } |
| } |
| |
| /* Received Uplink RLC data block. */ |
| int gprs_rlcmac_rcv_data_block(bitvec *rlc_block) |
| { |
| struct gprs_rlcmac_tbf *tbf; |
| |
| LOGP(DRLCMAC, LOGL_NOTICE, "RX: [PCU <- BTS] Uplink Data Block\n"); |
| RlcMacUplinkDataBlock_t * ul_data_block = (RlcMacUplinkDataBlock_t *)malloc(sizeof(RlcMacUplinkDataBlock_t)); |
| LOGP(DRLCMAC, LOGL_NOTICE, "+++++++++++++++++++++++++ RX : Uplink Data Block +++++++++++++++++++++++++\n"); |
| decode_gsm_rlcmac_uplink_data(rlc_block, ul_data_block); |
| LOGP(DRLCMAC, LOGL_NOTICE, "------------------------- RX : Uplink Data Block -------------------------\n"); |
| tbf = tbf_by_tfi(ul_data_block->TFI); |
| if (!tbf) { |
| return 0; |
| } |
| |
| if (ul_data_block->TI == 1) |
| { |
| tbf->tlli = ul_data_block->TLLI; |
| } |
| |
| 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); |
| if (ul_data_block->CV == 0) { |
| // Recieved last Data Block in this sequence. |
| gsmtap_send_llc(tbf->rlc_data, tbf->data_index); |
| if (!((ul_data_block->E_1 == 0)&&(ul_data_block->M[0] == 0)&&(ul_data_block->E[0] == 1))) |
| tbf->state = GPRS_RLCMAC_WAIT_NEXT_DATA_SEQ; |
| else |
| tbf->state = GPRS_RLCMAC_WAIT_DATA_SEQ_START; |
| gprs_rlcmac_tx_ul_ud(tbf); |
| } else { |
| tbf->bsn = ul_data_block->BSN; |
| tbf->state = GPRS_RLCMAC_WAIT_NEXT_DATA_BLOCK; |
| } |
| } |
| 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); |
| if (!((ul_data_block->E_1 == 0)&&(ul_data_block->M[0] == 0)&&(ul_data_block->E[0] == 1))) |
| tbf->state = GPRS_RLCMAC_WAIT_NEXT_DATA_SEQ; |
| else |
| tbf->state = GPRS_RLCMAC_WAIT_DATA_SEQ_START; |
| gprs_rlcmac_tx_ul_ud(tbf); |
| } 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(bitvec *rlc_block) |
| { |
| uint8_t tfi = 0; |
| uint32_t tlli = 0; |
| struct gprs_rlcmac_tbf *tbf; |
| struct gprs_rlcmac_tbf *ul_tbf; |
| |
| RlcMacUplink_t * ul_control_block = (RlcMacUplink_t *)malloc(sizeof(RlcMacUplink_t)); |
| LOGP(DRLCMAC, LOGL_NOTICE, "+++++++++++++++++++++++++ RX : Uplink Control Block +++++++++++++++++++++++++\n"); |
| decode_gsm_rlcmac_uplink(rlc_block, ul_control_block); |
| LOGPC(DRLCMAC, LOGL_NOTICE, "\n"); |
| LOGP(DRLCMAC, LOGL_NOTICE, "------------------------- RX : Uplink Control Block -------------------------\n"); |
| switch (ul_control_block->u.MESSAGE_TYPE) { |
| case MT_PACKET_CONTROL_ACK: |
| tlli = ul_control_block->u.Packet_Control_Acknowledgement.TLLI; |
| tbf = tbf_by_tlli(tlli); |
| if (!tbf) { |
| return 0; |
| } |
| LOGP(DRLCMAC, LOGL_NOTICE, "RX: [PCU <- BTS] TFI: %u TLLI: 0x%08x Packet Control Ack\n", tbf->tfi, tbf->tlli); |
| LOGP(DRLCMAC, LOGL_NOTICE, "TBF: [UPLINK] END TFI: %u TLLI: 0x%08x \n", tbf->tfi, tbf->tlli); |
| 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; |
| } |
| LOGP(DRLCMAC, LOGL_NOTICE, "RX: [PCU <- BTS] TFI: %u TLLI: 0x%08x Packet Downlink Ack/Nack\n", tbf->tfi, tbf->tlli); |
| tlli = tbf->tlli; |
| LOGP(DRLCMAC, LOGL_NOTICE, "TBF: [DOWNLINK] END TFI: %u TLLI: 0x%08x \n", tbf->tfi, tbf->tlli); |
| tbf_free(tbf); |
| break; |
| } |
| free(ul_control_block); |
| return 1; |
| } |
| |
| void gprs_rlcmac_rcv_block(bitvec *rlc_block) |
| { |
| unsigned readIndex = 0; |
| unsigned payload = bitvec_read_field(rlc_block, 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"); |
| } |
| } |
| |
| int gprs_rlcmac_rcv_rach(uint8_t ra, uint32_t Fn, uint16_t ta) |
| { |
| struct gprs_rlcmac_tbf *tbf; |
| |
| // Create new TBF |
| int tfi = tfi_alloc(); |
| if (tfi < 0) { |
| return tfi; |
| } |
| tbf = tbf_alloc(tfi); |
| tbf->direction = GPRS_RLCMAC_UL_TBF; |
| tbf->state = GPRS_RLCMAC_WAIT_DATA_SEQ_START; |
| LOGP(DRLCMAC, LOGL_NOTICE, "TBF: [UPLINK] START TFI: %u\n", tbf->tfi); |
| LOGP(DRLCMAC, LOGL_NOTICE, "RX: [PCU <- BTS] TFI: %u RACH\n", tbf->tfi); |
| LOGP(DRLCMAC, LOGL_NOTICE, "TX: [PCU -> BTS] TFI: %u Packet Immidiate Assignment\n", tbf->tfi); |
| bitvec *immediate_assignment = bitvec_alloc(23); |
| bitvec_unhex(immediate_assignment, "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); |
| int len = write_immediate_assignment(immediate_assignment, 0, ra, Fn, ta, tbf->tfi); |
| pcu_l1if_tx(immediate_assignment, GsmL1_Sapi_Agch, len); |
| bitvec_free(immediate_assignment); |
| } |
| |
| // Send RLC data to OpenBTS. |
| void gprs_rlcmac_tx_dl_data_block(uint32_t tlli, uint8_t tfi, uint8_t *pdu, int start_index, int end_index, uint8_t bsn, uint8_t fbi) |
| { |
| int spare_len = 0; |
| bitvec *data_block_vector = bitvec_alloc(BLOCK_LEN); |
| bitvec_unhex(data_block_vector, "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 = tfi; |
| data_block->FBI = fbi; |
| data_block->BSN = bsn; |
| |
| // Last RLC data block of current LLC PDU |
| if (fbi == 1) |
| { |
| data_block->E_1 = 0; |
| data_block->M[0] = 0; |
| data_block->E[0] = 1; |
| // Singular case, TS 44.060 10.4.14 |
| if ((end_index - start_index) == (BLOCK_LEN - 3)) |
| { |
| data_block->FBI = 0; |
| data_block->LENGTH_INDICATOR[0] = 0; |
| spare_len = 0; |
| end_index--; |
| } |
| else |
| { |
| data_block->LENGTH_INDICATOR[0] = end_index-start_index; |
| spare_len = BLOCK_LEN - 4 - data_block->LENGTH_INDICATOR[0]; |
| } |
| } |
| else |
| { |
| data_block->E_1 = 1; |
| } |
| |
| int data_oct_num = 0; |
| int i = 0; |
| // Pack LLC PDU into RLC data field |
| for(i = start_index; i < end_index; i++) { |
| data_block->RLC_DATA[data_oct_num] = pdu[i]; |
| data_oct_num++; |
| } |
| // Fill spare bits |
| for(i = data_oct_num; i < data_oct_num + spare_len; i++) { |
| data_block->RLC_DATA[i] = 0x2b; |
| } |
| LOGP(DRLCMAC, LOGL_NOTICE, "TX: [PCU -> BTS] Downlink Data Block\n"); |
| LOGP(DRLCMAC, LOGL_NOTICE, "+++++++++++++++++++++++++ TX : Downlink Data Block +++++++++++++++++++++++++\n"); |
| encode_gsm_rlcmac_downlink_data(data_block_vector, data_block); |
| LOGP(DRLCMAC, LOGL_NOTICE, "------------------------- TX : Downlink Data Block -------------------------\n"); |
| free(data_block); |
| pcu_l1if_tx(data_block_vector, GsmL1_Sapi_Pdtch); |
| bitvec_free(data_block_vector); |
| |
| // Singular case, TS 44.060 10.4.14 |
| if ((fbi == 1)&&((end_index + 1 - start_index) == (BLOCK_LEN - 3))) |
| { |
| gprs_rlcmac_tx_dl_data_block(tlli, tfi, pdu, end_index, end_index+1, bsn+1, fbi); |
| } |
| } |
| |
| int gprs_rlcmac_segment_llc_pdu(struct gprs_rlcmac_tbf *tbf) |
| { |
| int fbi = 0; |
| int bsn = 0; |
| int num_blocks = 0; // number of RLC data blocks necessary for LLC PDU transmission |
| |
| |
| // LLC PDU fits into one RLC data block with optional LI field. |
| if (tbf->data_index < BLOCK_LEN - 4) |
| { |
| fbi = 1; |
| gprs_rlcmac_tx_dl_data_block(tbf->tlli, tbf->tfi, tbf->rlc_data, 0, tbf->data_index, bsn, fbi); |
| } |
| // Necessary several RLC data blocks for transmit LLC PDU. |
| else |
| { |
| // length of RLC data field in block (no optional octets) |
| int block_data_len = BLOCK_LEN - 3; |
| |
| // number of blocks with 20 octets length RLC data field |
| num_blocks = tbf->data_index/block_data_len; |
| |
| // rest of LLC PDU, which doesn't fit into data blocks with 20 octets RLC data field |
| int rest_len = tbf->data_index%BLOCK_DATA_LEN; |
| if (rest_len > 0) |
| { |
| // add one block for transmission rest of LLC PDU |
| num_blocks++; |
| } |
| |
| int start_index = 0; |
| int end_index = 0; |
| |
| // Transmit all RLC data blocks of current LLC PDU to MS |
| for (bsn = 0; bsn < num_blocks; bsn++) |
| { |
| if (bsn == 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->tfi, tbf->rlc_data, start_index, end_index, bsn, fbi); |
| start_index += block_data_len; |
| } |
| } |
| } |
| |
| /* 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_NOTICE, "TX: [PCU -> SGSN ] TFI: %u TLLI: 0x%08x DataLen: %u", tbf->tfi, tbf->tlli, tbf->data_index); |
| //LOGP(DBSSGP, LOGL_NOTICE, " Data = "); |
| //for (unsigned i = 0; i < tbf->data_index; i++) |
| // LOGPC(DBSSGP, LOGL_NOTICE, "%02x ", tbf->rlc_data[i]); |
| |
| bctx->cell_id = CELL_ID; |
| bctx->nsei = NSEI; |
| bctx->ra_id.mnc = MNC; |
| bctx->ra_id.mcc = MCC; |
| bctx->ra_id.lac = PCU_LAC; |
| bctx->ra_id.rac = PCU_RAC; |
| bctx->bvci = BVCI; |
| |
| 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); |
| } |
| |
| void gprs_rlcmac_downlink_assignment(gprs_rlcmac_tbf *tbf) |
| { |
| LOGP(DRLCMAC, LOGL_NOTICE, "TX: [PCU -> BTS] TFI: %u TLLI: 0x%08x Immidiate Assignment (CCCH)\n", tbf->tfi, tbf->tlli); |
| bitvec *immediate_assignment = bitvec_alloc(23); |
| bitvec_unhex(immediate_assignment, "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); |
| int len = write_immediate_assignment(immediate_assignment, 1, 125, get_current_fn(), (l1fh->fl1h)->channel_info.ta, tbf->tfi, tbf->tlli); |
| pcu_l1if_tx(immediate_assignment, GsmL1_Sapi_Agch, len); |
| bitvec_free(immediate_assignment); |
| tbf_gsm_timer_start(tbf, 0, 120); |
| } |
| |
| void gprs_rlcmac_packet_downlink_assignment(gprs_rlcmac_tbf *tbf) |
| { |
| LOGP(DRLCMAC, LOGL_NOTICE, "TX: [PCU -> BTS] TFI: %u TLLI: 0x%08x Packet DL Assignment\n", tbf->tfi, tbf->tlli); |
| bitvec *packet_downlink_assignment_vec = bitvec_alloc(23); |
| bitvec_unhex(packet_downlink_assignment_vec, "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); |
| write_packet_downlink_assignment(packet_downlink_assignment_vec, tbf->tfi, tbf->tlli, (l1fh->fl1h)->channel_info.tn, |
| (l1fh->fl1h)->channel_info.ta, (l1fh->fl1h)->channel_info.tsc); |
| RlcMacDownlink_t * packet_downlink_assignment = (RlcMacDownlink_t *)malloc(sizeof(RlcMacDownlink_t)); |
| LOGP(DRLCMAC, LOGL_NOTICE, "+++++++++++++++++++++++++ TX : Packet Downlink Assignment +++++++++++++++++++++++++\n"); |
| decode_gsm_rlcmac_downlink(packet_downlink_assignment_vec, packet_downlink_assignment); |
| LOGPC(DRLCMAC, LOGL_NOTICE, "\n"); |
| LOGP(DRLCMAC, LOGL_NOTICE, "------------------------- TX : Packet Downlink Assignment -------------------------\n"); |
| free(packet_downlink_assignment); |
| pcu_l1if_tx(packet_downlink_assignment_vec, GsmL1_Sapi_Pacch); |
| bitvec_free(packet_downlink_assignment_vec); |
| tbf_gsm_timer_start(tbf, 0, 120); |
| } |