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-rw-r--r--src/gprs_rlcmac.cpp840
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diff --git a/src/gprs_rlcmac.cpp b/src/gprs_rlcmac.cpp
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+/* 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);
+ tbf->state = GPRS_RLCMAC_WAIT_NEXT_DATA_SEQ;
+ 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);
+ tbf->state = GPRS_RLCMAC_WAIT_NEXT_DATA_SEQ;
+ 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);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-08 05:59:47 +0000