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initial import of Osmocom TETRA phy and lower MAC code

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changes/47/1447/1
Harald Welte 12 years ago
parent a4c4e5a1ab
commit 7ee08faee0
45 changed files with 4217 additions and 0 deletions
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  1. 8
      src/.gitignore
  2. 25
      src/Makefile
  3. 74
      src/burst_test.c
  4. 351
      src/conv_enc_test.c
  5. 73
      src/crc_test.c
  6. 117
      src/float_to_bits.c
  7. 106
      src/lower_mac/crc_simple.c
  8. 48
      src/lower_mac/crc_simple.h
  9. 301
      src/lower_mac/tetra_conv_enc.c
  10. 33
      src/lower_mac/tetra_conv_enc.h
  11. 59
      src/lower_mac/tetra_interleave.c
  12. 12
      src/lower_mac/tetra_interleave.h
  13. 257
      src/lower_mac/tetra_lower_mac.c
  14. 96
      src/lower_mac/tetra_rm3014.c
  15. 16
      src/lower_mac/tetra_rm3014.h
  16. 99
      src/lower_mac/tetra_scramb.c
  17. 23
      src/lower_mac/tetra_scramb.h
  18. 25
      src/lower_mac/viterbi.c
  19. 6
      src/lower_mac/viterbi.h
  20. 163
      src/lower_mac/viterbi_cch.c
  21. 7
      src/lower_mac/viterbi_cch.h
  22. 159
      src/lower_mac/viterbi_tch.c
  23. 7
      src/lower_mac/viterbi_tch.h
  24. 19
      src/osmo_prim.h
  25. 345
      src/phy/tetra_burst.c
  26. 35
      src/phy/tetra_burst.h
  27. 141
      src/phy/tetra_burst_sync.c
  28. 26
      src/phy/tetra_burst_sync.h
  29. 99
      src/testpdu.c
  30. 10
      src/testpdu.h
  31. 157
      src/tetra_common.c
  32. 52
      src/tetra_common.h
  33. 134
      src/tetra_gsmtap.c
  34. 13
      src/tetra_gsmtap.h
  35. 375
      src/tetra_mac_pdu.c
  36. 221
      src/tetra_mac_pdu.h
  37. 38
      src/tetra_mle_pdu.c
  38. 17
      src/tetra_mle_pdu.h
  39. 46
      src/tetra_mm_pdu.c
  40. 26
      src/tetra_mm_pdu.h
  41. 48
      src/tetra_prim.h
  42. 100
      src/tetra_tdma.c
  43. 20
      src/tetra_tdma.h
  44. 222
      src/tetra_upper_mac.c
  45. 8
      src/tetra_upper_mac.h

8
src/.gitignore vendored
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*.o
*.a
*.pyc
.*.swp
conv_enc_test
burst_test
float_to_bits
crc_test

25
src/Makefile
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CFLAGS=-g -O0 -Wall `pkg-config --cflags libosmocore 2> /dev/null` -I.
LDFLAGS=`pkg-config --libs libosmocore 2> /dev/null` -losmocore
all: conv_enc_test crc_test burst_test float_to_bits
%.o: %.c
$(CC) $(CFLAGS) -c $^ -o $@
libosmo-tetra-phy.a: phy/tetra_burst_sync.o phy/tetra_burst.o
$(AR) r $@ $^
libosmo-tetra-mac.a: lower_mac/tetra_conv_enc.o tetra_tdma.o lower_mac/tetra_scramb.o lower_mac/tetra_rm3014.o lower_mac/tetra_interleave.o lower_mac/crc_simple.o tetra_common.o lower_mac/viterbi.o lower_mac/viterbi_cch.o lower_mac/viterbi_tch.o lower_mac/tetra_lower_mac.o tetra_upper_mac.o tetra_mac_pdu.o tetra_mle_pdu.o tetra_mm_pdu.o tetra_gsmtap.o
$(AR) r $@ $^
float_to_bits: float_to_bits.o
crc_test: crc_test.o tetra_common.o libosmo-tetra-mac.a
burst_test: burst_test.o libosmo-tetra-phy.a libosmo-tetra-mac.a
conv_enc_test: conv_enc_test.o testpdu.o libosmo-tetra-phy.a libosmo-tetra-mac.a
$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^
clean:
@rm -f conv_enc_test crc_test burst_test float_to_bits *.o phy/*.o lower_mac/*.o *.a

74
src/burst_test.c
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/* Test program for tetra burst synchronizer */
/* (C) 2011 by Harald Welte <laforge@gnumonks.org>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <osmocore/utils.h>
#include "tetra_common.h"
#include <phy/tetra_burst.h>
#include <phy/tetra_burst_sync.h>
#include "tetra_gsmtap.h"
int main(int argc, char **argv)
{
int fd;
struct tetra_rx_state *trs;
if (argc < 2) {
fprintf(stderr, "Usage: %s <file_with_1_byte_per_bit>\n", argv[0]);
exit(1);
}
fd = open(argv[1], O_RDONLY);
if (fd < 0) {
perror("open");
exit(2);
}
tetra_gsmtap_init("localhost", 0);
trs = calloc(1, sizeof(*trs));
while (1) {
uint8_t buf[64];
int len;
len = read(fd, buf, sizeof(buf));
if (len < 0) {
perror("read");
exit(1);
} else if (len == 0) {
printf("EOF");
break;
}
tetra_burst_sync_in(trs, buf, len);
}
free(trs);
exit(0);
}

351
src/conv_enc_test.c
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/* (C) 2011 by Harald Welte <laforge@gnumonks.org>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <time.h>
#include <arpa/inet.h>
#include <osmocore/utils.h>
#include <osmocore/bits.h>
#include "tetra_common.h"
#include <lower_mac/crc_simple.h>
#include <lower_mac/tetra_conv_enc.h>
#include <lower_mac/tetra_interleave.h>
#include <lower_mac/tetra_scramb.h>
#include <lower_mac/tetra_rm3014.h>
#include <lower_mac/viterbi.h>
#include <phy/tetra_burst.h>
#include "testpdu.h"
#define swap16(x) ((x)<<8)|((x)>>8)
static unsigned int num_crc_err;
/* incoming TP-SAP UNITDATA.ind from PHY into lower MAC */
void tp_sap_udata_ind(enum tp_sap_data_type type, const uint8_t *bits, unsigned int len, void *priv)
{
}
static void decode_schf(const uint8_t *bits)
{
uint8_t type4[1024];
uint8_t type3dp[1024*4];
uint8_t type3[1024];
uint8_t type2[1024];
printf("SCH/f type5: %s\n", bitdump(bits, 432));
memcpy(type4, bits, 432);
tetra_scramb_bits(SCRAMB_INIT, type4, 432);
printf("SCH/F type4: %s\n", bitdump(type4, 432));
/* Run (120,11) block deinterleaving: type-3 bits */
block_deinterleave(432, 103, type4, type3);
printf("SCH/F type3: %s\n", bitdump(type3, 432));
/* De-puncture */
memset(type3dp, 0xff, sizeof(type3dp));
tetra_rcpc_depunct(TETRA_RCPC_PUNCT_2_3, type3, 432, type3dp);
printf("SCH/F type3dp: %s\n", bitdump(type3dp, 288*4));
viterbi_dec_sb1_wrapper(type3dp, type2, 288);
printf("SCH/F type2: %s\n", bitdump(type2, 288));
{
uint16_t crc;
crc = crc16_ccitt_bits(type2, 288-4);
printf("CRC COMP: 0x%04x ", crc);
if (crc == 0x1d0f)
printf("OK\n");
else {
printf("WRONG\n");
num_crc_err++;
}
}
printf("SCH/F type1: %s\n", bitdump(type2, 268));
}
/* Build a full 'downlink continuous SYNC burst' from SYSINFO-PDU and SYNC-PDU */
int build_ndb_schf()
{
/* input: 268 type-1 bits */
uint8_t type2[284];
uint8_t master[284*4];
uint8_t type3[432];
uint8_t type4[432];
uint8_t type5[432];
uint8_t bb_type5[30];
uint8_t burst[255*2];
uint16_t crc;
uint8_t *cur;
uint32_t bb_rm3014, bb_rm3014_be;
memset(type2, 0, sizeof(type2));
cur = type2;
/* Use pdu_sync from testpdu.c */
cur += osmo_pbit2ubit(type2, pdu_schf, 268);
crc = ~crc16_ccitt_bits(type2, 268);
crc = swap16(crc);
cur += osmo_pbit2ubit(cur, (uint8_t *) &crc, 16);
/* Append 4 tail bits: type-2 bits */
cur += 4;
printf("SCH/F type2: %s\n", bitdump(type2, 288));
/* Run rate 2/3 RCPC code: type-3 bits*/
{
struct conv_enc_state *ces = calloc(1, sizeof(*ces));
conv_enc_init(ces);
conv_enc_input(ces, type2, 288, master);
get_punctured_rate(TETRA_RCPC_PUNCT_2_3, master, 432, type3);
free(ces);
}
printf("SCH/F type3: %s\n", bitdump(type3, 432));
/* Run (432,103) block interleaving: type-4 bits */
block_interleave(432, 103, type3, type4);
printf("SCH/F type4: %s\n", bitdump(type4, 432));
/* Run scrambling (all-zero): type-5 bits */
memcpy(type5, type4, 432);
tetra_scramb_bits(SCRAMB_INIT, type5, 432);
printf("SCH/F type5: %s\n", bitdump(type5, 432));
decode_schf(type5);
/* Use pdu_acc_ass from testpdu.c */
/* Run it through (30,14) RM code: type-2=3=4 bits */
printf("AACH type-1: %s\n", bitdump(pdu_acc_ass, 2));
bb_rm3014 = tetra_rm3014_compute(*(uint16_t *)pdu_acc_ass);
printf("AACH RM3014: 0x0%x\n", bb_rm3014);
/* convert to big endian */
bb_rm3014_be = htonl(bb_rm3014);
/* shift two bits left as it is only a 30 bit value */
bb_rm3014_be <<= 2;
osmo_pbit2ubit(bb_type5, (uint8_t *) &bb_rm3014_be, 30);
/* Run scrambling (all-zero): type-5 bits */
printf("AACH type-5: %s\n", bitdump(bb_type5, 30));
/* Finally, hand it into the physical layer */
build_norm_c_d_burst(burst, type5, bb_type5, type5+216, 0);
printf("cont norm DL burst: %s\n", bitdump(burst, 255*2));
return 0;
}
static void decode_sb1(const uint8_t *bits)
{
uint8_t type4[1024];
uint8_t type3dp[1024*4];
uint8_t type3[1024];
uint8_t type2[1024];
printf("SB1 type5: %s\n", bitdump(bits, 120));
memcpy(type4, bits, 120);
tetra_scramb_bits(SCRAMB_INIT, type4, 120);
printf("SB1 type4: %s\n", bitdump(type4, 120));
/* Run (120,11) block deinterleaving: type-3 bits */
block_deinterleave(120, 11, type4, type3);
printf("SB1 type3: %s\n", bitdump(type3, 120));
/* De-puncture */
memset(type3dp, 0xff, sizeof(type3dp));
tetra_rcpc_depunct(TETRA_RCPC_PUNCT_2_3, type3, 120, type3dp);
printf("SB1 type3dp: %s\n", bitdump(type3dp, 80*4));
viterbi_dec_sb1_wrapper(type3dp, type2, 80);
printf("SB1 type2: %s\n", bitdump(type2, 80));
{
uint16_t crc;
crc = crc16_ccitt_bits(type2, 76);
printf("CRC COMP: 0x%04x ", crc);
if (crc == 0x1d0f)
printf("OK\n");
else {
printf("WRONG\n");
num_crc_err++;
}
}
printf("TN %s ", bitdump(type2+10, 2));
printf("MCC %s ", bitdump(type2+31, 10));
printf("MNC %s\n", bitdump(type2+41, 14));
}
/* Build a full 'downlink continuous SYNC burst' from SYSINFO-PDU and SYNC-PDU */
int build_sb()
{
uint8_t sb_type2[80];
uint8_t sb_master[80*4];
uint8_t sb_type3[120];
uint8_t sb_type4[120];
uint8_t sb_type5[120];
uint8_t si_type2[140];
uint8_t si_master[140*4];
uint8_t si_type3[216];
uint8_t si_type4[216];
uint8_t si_type5[216];
uint8_t bb_type5[30];
uint8_t burst[255*2];
uint16_t crc;
uint8_t *cur;
uint32_t bb_rm3014, bb_rm3014_be;
memset(sb_type2, 0, sizeof(sb_type2));
cur = sb_type2;
/* Use pdu_sync from testpdu.c */
cur += osmo_pbit2ubit(sb_type2, pdu_sync, 60);
crc = ~crc16_ccitt_bits(sb_type2, 60);
crc = swap16(crc);
cur += osmo_pbit2ubit(cur, (uint8_t *) &crc, 16);
/* Append 4 tail bits: type-2 bits */
cur += 4;
printf("SYNC type2: %s\n", bitdump(sb_type2, 80));
/* Run rate 2/3 RCPC code: type-3 bits*/
{
struct conv_enc_state *ces = calloc(1, sizeof(*ces));
conv_enc_init(ces);
conv_enc_input(ces, sb_type2, 80, sb_master);
get_punctured_rate(TETRA_RCPC_PUNCT_2_3, sb_master, 120, sb_type3);
free(ces);
}
printf("SYNC type3: %s\n", bitdump(sb_type3, 120));
/* Run (120,11) block interleaving: type-4 bits */
block_interleave(120, 11, sb_type3, sb_type4);
printf("SYNC type4: %s\n", bitdump(sb_type4, 120));
/* Run scrambling (all-zero): type-5 bits */
memcpy(sb_type5, sb_type4, 120);
tetra_scramb_bits(SCRAMB_INIT, sb_type5, 120);
printf("SYNC type5: %s\n", bitdump(sb_type5, 120));
decode_sb1(sb_type5);
/* Use pdu_sysinfo from testpdu.c */
memset(si_type2, 0, sizeof(si_type2));
cur = si_type2;
cur += osmo_pbit2ubit(si_type2, pdu_sysinfo, 124);
/* Run it through CRC16-CCITT */
crc = ~crc16_ccitt_bits(si_type2, 124);
crc = swap16(crc);
cur += osmo_pbit2ubit(cur, (uint8_t *) &crc, 16);
/* Append 4 tail bits: type-2 bits */
cur += 4;
printf("SI type2: %s\n", bitdump(si_type2, 140));
/* Run rate 2/3 RCPC code: type-3 bits */
{
struct conv_enc_state *ces = calloc(1, sizeof(*ces));
conv_enc_init(ces);
conv_enc_input(ces, sb_type2, 144, si_master);
get_punctured_rate(TETRA_RCPC_PUNCT_2_3, si_master, 216, si_type3);
free(ces);
}
printf("SI type3: %s\n", bitdump(si_type3, 216));
/* Run (216,101) block interleaving: type-4 bits */
block_interleave(216, 101, si_type3, si_type4);
printf("SI type4: %s\n", bitdump(si_type4, 216));
/* Run scrambling (all-zero): type-5 bits */
memcpy(si_type5, si_type4, 216);
/* Use pdu_acc_ass from testpdu.c */
/* Run it through (30,14) RM code: type-2=3=4 bits */
printf("AACH type-1: %s\n", bitdump(pdu_acc_ass, 2));
bb_rm3014 = tetra_rm3014_compute(*(uint16_t *)pdu_acc_ass);
printf("AACH RM3014: 0x0%x\n", bb_rm3014);
/* convert to big endian */
bb_rm3014_be = htonl(bb_rm3014);
/* shift two bits left as it is only a 30 bit value */
bb_rm3014_be <<= 2;
osmo_pbit2ubit(bb_type5, (uint8_t *) &bb_rm3014_be, 30);
/* Run scrambling (all-zero): type-5 bits */
printf("AACH type-5: %s\n", bitdump(bb_type5, 30));
/* Finally, hand it into the physical layer */
build_sync_c_d_burst(burst, sb_type5, bb_type5, si_type5);
printf("cont sync DL burst: %s\n", bitdump(burst, 255*2));
return 0;
}
int main(int argc, char **argv)
{
int err, i;
uint16_t out;
uint32_t ret;
/* first: run some subsystem tests */
ret = tetra_punct_test();
if (ret < 0)
exit(1);
tetra_rm3014_init();
#if 0
ret = tetra_rm3014_compute(0x1001);
printf("RM3014: 0x%08x\n", ret);
err = tetra_rm3014_decode(ret, &out);
printf("RM3014: 0x%x error: %d\n", out, err);
#endif
/* finally, build some test PDUs and encocde them */
testpdu_init();
#if 0
build_sb();
build_ndb_schf();
#else
/* iterate over various random PDUs and throw them throguh the viterbi */
srand(time(NULL));
for (i = 0; i < 100; i++) {
uint32_t r = rand();
osmo_pbit2ubit(pdu_sync, (uint8_t *) &r, 32);
osmo_pbit2ubit(pdu_sync+32, (uint8_t *)&r, 60-32);
//build_sb();
osmo_pbit2ubit(pdu_schf, (uint8_t *) &r, 32);
osmo_pbit2ubit(pdu_schf+32, (uint8_t *)&r, 60-32);
build_ndb_schf();
}
#endif
printf("total number of CRC Errors: %u\n", num_crc_err);
exit(0);
}

73
src/crc_test.c
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/* (C) 2011 by Holger Hans Peter Freyther
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <stdio.h>
#include "tetra_common.h"
#include <lower_mac/crc_simple.h>
int main(int argc, char **argv)
{
uint8_t input1[] = { 0x01 };
uint16_t crc;
crc = crc16_itut_bytes(0x0, input1, 8);
printf("The CRC is now: %u/0x%x\n", crc, crc);
crc = crc16_itut_bits(0x0, input1, 1);
printf("The CRC is now: %d/0x%x\n", crc, crc);
crc = crc16_itut_bytes(0xFFFF, input1, 8);
printf("The CRC is now: %u/0x%x\n", crc, crc);
crc = crc16_itut_bits(0xFFFF, input1, 1);
printf("The CRC is now: %d/0x%x\n", crc, crc);
/* actual CRC-CCIT usage */
uint8_t input2[] = {
0, 0, 0, 1, 0, 0, 0, 0,
1, 0, 1, 1, 0, 0, 0, 0,
1, 0, 1, 1, 1, 1, 1, 0,
0, 0, 0, 0, 0, 0, 0, 0,
1, 0, 0, 0, 0, 0, 1, 1,
0, 0, 0, 0, 0, 1, 1, 1,
1, 1, 0, 1, 0, 0, 1, 1,
0, 0, 1, 1,
/* checksum */
1, 1, 0, 1, 1, 1, 1, 0,
1, 1, 1, 1, 0, 0, 0, 1,
/* tail bits */
0, 0, 0, 0 };
crc = ~crc16_itut_bits(0xffff, input2, 60);
printf("The CRC is now: %d/0x%x\n", crc, crc);
/* swap the bytes */
crc = (crc << 8) | (crc >> 8);
osmo_pbit2ubit(&input2[60], (uint8_t *)&crc, 16);
crc = crc16_itut_bits(0xFFFF, input2, 60 + 16);
printf("The CRC is now: %d/0x%x\n", crc, crc);
if (crc == 0x1d0f)
printf("Decoded successfully.\n");
else
printf("Failed to decode.\n");
return 0;
}

117
src/float_to_bits.c
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/* Convert floating point symbols in the range +3/-3 to hard bits,
* in the 1-bit-per-byte format */
/* (C) 2011 by Harald Welte <laforge@gnumonks.org>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <stdint.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
static int process_sym_fl(float offset, float fl)
{
int ret;
fl += offset;
/* very simplistic scheme */
if (fl > 2)
ret = 3;
else if (fl > 0)
ret = 1;
else if (fl < -2)
ret = -3;
else
ret = -1;
return ret;
}
static void sym_int2bits(int sym, uint8_t *ret)
{
switch (sym) {
case -3:
ret[0] = 1;
ret[1] = 1;
break;
case 1:
ret[0] = 0;
ret[1] = 0;
break;
//case -1:
case 3:
ret[0] = 0;
ret[1] = 1;
break;
//case 3:
case -1:
ret[0] = 1;
ret[1] = 0;
break;
}
}
int main(int argc, char **argv)
{
int fd, fd_out;
if (argc < 3) {
fprintf(stderr, "Usage: %s <infile> <outfile>\n", argv[0]);
exit(2);
}
fd = open(argv[1], O_RDONLY);
if (fd < 0) {
perror("open infile");
exit(1);
}
fd_out = creat(argv[2], 0660);
if (fd_out < 0) {
perror("open outfile");
exit(1);
}
while (1) {
int rc;
float fl;
uint8_t bits[2];
rc = read(fd, &fl, sizeof(fl));
if (rc < 0) {
perror("read");
exit(1);
} else if (rc == 0)
break;
rc = process_sym_fl(0.3f, fl);
sym_int2bits(rc, bits);
//printf("%2d %1u %1u %f\n", rc, bits[0], bits[1], fl);
//printf("%1u%1u", bits[0], bits[1]);
rc = write(fd_out, bits, 2);
if (rc < 0) {
perror("write");
exit(1);
} else if (rc == 0)
break;
}
exit(0);
}

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src/lower_mac/crc_simple.c
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/* CRC16 (most likely the ITU variant) working on plain bits as a trial
* to find out if simple padding to the right is going to be enough
*/
/* (C) 2011 by Holger Hans Peter Freyther
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <lower_mac/crc_simple.h>
#include <stdio.h>
/**
* X.25 rec 2.2.7.4 Frame Check Sequence. This should be
* CRC ITU-T from the kernel or such.
*/
#define GEN_POLY 0x1021
uint16_t get_nth_bit(const uint8_t *input, int _bit)
{
uint16_t val;
int byte = _bit / 8;
int bit = 7 - _bit % 8;
val = (input[byte] & (1 << bit)) >> bit;
return val;
}
/**
* This is mostly from http://en.wikipedia.org/wiki/Computation_of_CRC
* Code fragment 2. Due some stupidity it took longer to implement than
* it should have taken.
*/
uint16_t crc16_itut_bytes(uint16_t crc, const uint8_t *input, int number_bits)
{
int i;
for (i = 0; i < number_bits; ++i) {
uint16_t bit = get_nth_bit(input, i);
crc ^= bit << 15;
if ((crc & 0x8000)) {
crc <<= 1;
crc ^= GEN_POLY;
} else {
crc <<= 1;
}
}
return crc;
}
uint16_t crc16_itut_bits(uint16_t crc, const uint8_t *input, int number_bits)
{
int i;
for (i = 0; i < number_bits; ++i) {
uint16_t bit = input[i] & 0x1;
crc ^= bit << 15;
if ((crc & 0x8000)) {
crc <<= 1;
crc ^= GEN_POLY;
} else {
crc <<= 1;
}
}
return crc;
}
uint16_t crc16_itut_poly(uint16_t crc, uint32_t poly, const uint8_t *input, int number_bits)
{
int i;
for (i = 0; i < number_bits; ++i) {
uint16_t bit = input[i] & 0x1;
crc ^= bit << 15;
if ((crc & 0x8000)) {
crc <<= 1;
crc ^= poly;
} else {
crc <<= 1;
}
}
return crc;
}
uint16_t crc16_ccitt_bits(uint8_t *bits, unsigned int len)
{
return crc16_itut_bits(0xffff, bits, len);
}

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/* (C) 2011 by Holger Hans Peter Freyther
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef CRC_16
#define CRC_16
#include <stdint.h>
/**
* Code to generate a CRC16-ITU-T as of the X.25 specification and
* compatible with Linux's implementations. At least the polynom is
* coming from the X.25 spec.
*/
/**
* This is working of bits packed together. The high bits will be
* accessed first. If you only pass one bit the array needs to contain
* a 0xF0 instead of a 0x01. This interface is compatible with the
* normal CRC interface (besides the length).
*/
uint16_t crc16_itut_bytes(uint16_t crc,
const uint8_t *input, const int number_bits);
/**
* Each byte contains one bit. Calculate the CRC16-ITU-T for it.
*/
uint16_t crc16_itut_bits(uint16_t crc,
const uint8_t *input, const int number_bits);
uint16_t crc16_ccitt_bits(uint8_t *bits, unsigned int len);
#endif

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/* Tetra convolutional encoder, according to ETSI EN 300 392-2 V3.2.1 (2007-09) */
/* This converts from type type-2 bits into type-3 bits */
/* (C) 2011 by Harald Welte <laforge@gnumonks.org>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <stdint.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <osmocore/utils.h>
#include <tetra_common.h>
#include <lower_mac/tetra_conv_enc.h>
static char *dump_state(struct conv_enc_state *ces)
{
static char pbuf[1024];
snprintf(pbuf, sizeof(pbuf), "%u-%u-%u-%u", ces->delayed[0],
ces->delayed[1], ces->delayed[2], ces->delayed[3]);
return pbuf;
}
/* Mother code according to Section 8.2.3.1.1 */
static uint8_t conv_enc_in_bit(struct conv_enc_state *ces, uint8_t bit, uint8_t *out)
{
uint8_t g1, g2, g3, g4;
uint8_t *delayed = ces->delayed;
DEBUGP("State in: %s, Input bit: %u: ", dump_state(ces), bit);
/* G1 = 1 + D + D4 */
g1 = (bit + delayed[0] + delayed[3]) % 2;
/* G2 = 1 + D2 + D3 + D4 */
g2 = (bit + delayed[1] + delayed[2] + delayed[3]) % 2;
/* G3 = 1 + D + D2 + D4 */
g3 = (bit + delayed[0] + delayed[1] + delayed[3]) % 2;
/* G4 = 1 + D + D3 + D4 */
g4 = (bit + delayed[0] + delayed[2] + delayed[3]) % 2;
/* shift the state and input our new bit */
ces->delayed[3] = ces->delayed[2];
ces->delayed[2] = ces->delayed[1];
ces->delayed[1] = ces->delayed[0];
ces->delayed[0] = bit;
DEBUGP("Output bits: %u-%u-%u-%u, State out: %s\n", g1, g2, g3, g4,
dump_state(ces));
*out++ = g1;
*out++ = g2;
*out++ = g3;
*out++ = g4;
return (g1 | (g2 << 1) | (g3 << 2) | (g4 << 3));
}
/* in: bit-per-byte (len), out: bit-per-byte (4*len) */
int conv_enc_input(struct conv_enc_state *ces, uint8_t *in, int len, uint8_t *out)
{
int i;
for (i = 0; i < len; i++) {
conv_enc_in_bit(ces, in[i], out);
out += 4;
}
return 0;
}
int conv_enc_init(struct conv_enc_state *ces)
{
memset(ces->delayed, 0, sizeof(ces->delayed));
return 0;
}
/* Puncturing */
const uint8_t P_rate2_3[] = { 0, 1, 2, 5 };
const uint8_t P_rate1_3[] = { 0, 1, 2, 3, 5, 6, 7 };
struct puncturer {
enum tetra_rcpc_puncturer type;
const uint8_t *P;
uint8_t t;
uint32_t (*i_func)(uint32_t j);
};
static uint32_t i_func_equals(uint32_t j)
{
return j;
}
static uint32_t i_func_292(uint32_t j)
{
return (j + ((j-1)/65));
}
static uint32_t i_func_148(uint32_t j)
{
return (j + ((j-1)/35));
}
/* Section 8.2.3.1.3 */
static const struct puncturer punct_2_3 = {
.type = TETRA_RCPC_PUNCT_2_3,
.P = P_rate2_3,
.t = 3,
.i_func = &i_func_equals,
};
/* Section 8.2.3.1.4 */
static const struct puncturer punct_1_3 = {
.type = TETRA_RCPC_PUNCT_1_3,
.P = P_rate1_3,
.t = 6,
.i_func = &i_func_equals,
};
/* Section 8.2.3.1.5 */
static const struct puncturer punct_292_432 = {
.type = TETRA_RCPC_PUNCT_292_432,
.P = P_rate2_3,
.t = 3,
.i_func = &i_func_292,
};
/* Section 8.2.3.1.6 */
static const struct puncturer punct_148_432 = {
.type = TETRA_RCPC_PUNCT_148_432,
.P = P_rate1_3,
.t = 6,
.i_func = &i_func_148,
};
static const struct puncturer *tetra_puncts[] = {
[TETRA_RCPC_PUNCT_2_3] = &punct_2_3,
[TETRA_RCPC_PUNCT_1_3] = &punct_1_3,
[TETRA_RCPC_PUNCT_292_432] = &punct_292_432,
[TETRA_RCPC_PUNCT_148_432] = &punct_148_432,
};
/* Puncture the mother code (in) and write 'len' symbols to out */
int get_punctured_rate(enum tetra_rcpc_puncturer pu, uint8_t *in, int len, uint8_t *out)
{
const struct puncturer *punct;
uint32_t i, j, k;
uint8_t t;
const uint8_t *P;
if (pu >= ARRAY_SIZE(tetra_puncts))
return -EINVAL;
punct = tetra_puncts[pu];
t = punct->t;
P = punct->P;
/* Section 8.2.3.1.2 */
for (j = 1; j <= len; j++) {
i = punct->i_func(j);
k = 8 * ((i-1)/t) + P[i - t*((i-1)/t)];
DEBUGP("j = %u, i = %u, k = %u\n", j, i, k);
out[j-1] = in[k-1];
}
return 0;
}
/* De-Puncture the 'len' type-3 bits (in) and write mother code to out */
int tetra_rcpc_depunct(enum tetra_rcpc_puncturer pu, const uint8_t *in, int len, uint8_t *out)
{
const struct puncturer *punct;
uint32_t i, j, k;
uint8_t t;
const uint8_t *P;
if (pu >= ARRAY_SIZE(tetra_puncts))
return -EINVAL;
punct = tetra_puncts[pu];
t = punct->t;
P = punct->P;
/* Section 8.2.3.1.2 */
for (j = 1; j <= len; j++) {
i = punct->i_func(j);
k = 8 * ((i-1)/t) + P[i - t*((i-1)/t)];
DEBUGP("j = %u, i = %u, k = %u\n", j, i, k);
out[k-1] = in[j-1];
}
return 0;
}
struct punct_test_param {
uint16_t type2_len;
uint16_t type3_len;
enum tetra_rcpc_puncturer punct;
};
static const struct punct_test_param punct_test_params[] = {
{ 80, 120, TETRA_RCPC_PUNCT_2_3 }, /* BSCH */
{ 292, 432, TETRA_RCPC_PUNCT_292_432 }, /* TCH/4.8 */
{ 148, 432, TETRA_RCPC_PUNCT_148_432 }, /* TCH/2.4 */
{ 144, 216, TETRA_RCPC_PUNCT_2_3 }, /* SCH/HD, BNCH, STCH */
{ 112, 168, TETRA_RCPC_PUNCT_2_3 }, /* SCH/HU */
{ 288, 432, TETRA_RCPC_PUNCT_2_3 }, /* SCH/F */
};
static int mother_memcmp(const uint8_t *mother, const uint8_t *depunct, int len)
{
unsigned int i, equal = 0;
for (i = 0; i < len; i++) {
/* ignore any 0xff-initialized part */
if (depunct[i] == 0xff)
continue;
if (depunct[i] != mother[i])
return -1;
equal++;
}
return equal;
}
static int test_one_punct(const struct punct_test_param *ptp)
{
uint8_t *mother_buf;
uint8_t *depunct_buf;
uint8_t *type3_buf;
int i, mother_len;
printf("==> Testing Puncture/Depuncture mode %u (%u/%u)\n",
ptp->punct, ptp->type2_len, ptp->type3_len);
mother_len = ptp->type2_len*4;
mother_buf = malloc(mother_len);
depunct_buf = malloc(ptp->type2_len*4);
type3_buf = malloc(ptp->type3_len);
/* initialize mother buffer with sequence of bytes starting at 0 */
for (i = 0; i < mother_len; i++)
mother_buf[i] = i & 0xff;
/* puncture the mother_buf to type3_buf using rate 2/3 on 60 bits */
get_punctured_rate(ptp->punct, mother_buf, ptp->type3_len, type3_buf);
/* initialize the de-punctured buffer */
memset(depunct_buf, 0xff, mother_len);
/* de-puncture into the depunct_buf (i.e. what happens at the receiver) */
tetra_rcpc_depunct(ptp->punct, type3_buf, ptp->type3_len, depunct_buf);
DEBUGP("MOTH: %s\n", hexdump(mother_buf, mother_len));
DEBUGP("PUNC: %s\n", hexdump(type3_buf, ptp->type3_len));
DEBUGP("DEPU: %s\n", hexdump(depunct_buf, mother_len));
i = mother_memcmp(mother_buf, depunct_buf, mother_len);
if (i < 0) {
fprintf(stderr, "Mother buf != Depunct buf\n");
return i;
} else if (i != ptp->type3_len) {
fprintf(stderr, "Depunct buf only has %u equal symbols, we need %u\n",
i, ptp->type3_len);
return -EINVAL;
}
free(type3_buf);
free(depunct_buf);
free(mother_buf);
return 0;
}
int tetra_punct_test(void)
{
int i, rc;
for (i = 0; i < ARRAY_SIZE(punct_test_params); i++) {
rc = test_one_punct(&punct_test_params[i]);
if (rc < 0)
return rc;
}
return 0;
}

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#ifndef TETRA_CONV_ENC_H
#define TETRA_CONV_ENC_H
#include <stdint.h>
struct conv_enc_state {
uint8_t delayed[4];
};
/* in: one-bit-per-byte out: 4bit-per-byte, both 'len' long */
int conv_enc_input(struct conv_enc_state *ces, uint8_t *in, int len, uint8_t *out);
int conv_enc_init(struct conv_enc_state *ces);
enum tetra_rcpc_puncturer {
TETRA_RCPC_PUNCT_2_3,
TETRA_RCPC_PUNCT_1_3,
TETRA_RCPC_PUNCT_292_432,
TETRA_RCPC_PUNCT_148_432,
};
/* Puncture the mother code (in) and write 'len' symbols to out */
int get_punctured_rate(enum tetra_rcpc_puncturer pu, uint8_t *in, int len, uint8_t *out);
/* De-Puncture the 'len' type-3 bits (in) and write mother code to out */
int tetra_rcpc_depunct(enum tetra_rcpc_puncturer pu, const uint8_t *in, int len, uint8_t *out);
/* Self-test the puncturing/de-puncturing */
int tetra_punct_test(void);
#endif /* TETRA_CONV_ENC_H */

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/* Tetra block interleaver, according to ETSI EN 300 392-2 V3.2.1 (2007-09) */
/* This converts from type type-3 bits into type-4 bits (and vice versa) */
/* (C) 2011 by Harald Welte <laforge@gnumonks.org>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <stdint.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <osmocore/utils.h>
#include <tetra_common.h>
#include <lower_mac/tetra_interleave.h>
/* Section 8.2.4.1 Block interleaving for phase modulation */
static uint32_t block_interl_func(uint32_t K, uint32_t a, uint32_t i)
{
return (1 + ( (a * i) % K));
}
void block_interleave(uint32_t K, uint32_t a, const uint8_t *in, uint8_t *out)
{
int i;
for (i = 1; i <= K; i++) {
uint32_t k = block_interl_func(K, a, i);
DEBUGP("interl: i=%u, k=%u\n", i, k);
out[k-1] = in[i-1];
}
}
void block_deinterleave(uint32_t K, uint32_t a, const uint8_t *in, uint8_t *out)
{
int i;
for (i = 1; i <= K; i++) {
uint32_t k = block_interl_func(K, a, i);
DEBUGP("deinterl: i=%u, k=%u\n", i, k);
out[i-1] = in[k-1];
}
}

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#ifndef TETRA_INTERLEAVE_H
#define TETRA_INTERLEAVE_H
/* Tetra block interleaver, according to ETSI EN 300 392-2 V3.2.1 (2007-09) */
/* This converts from type type-3 bits into type-4 bits (and vice versa) */
#include <stdint.h>
void block_interleave(uint32_t K, uint32_t a, const uint8_t *in, uint8_t *out);
void block_deinterleave(uint32_t K, uint32_t a, const uint8_t *in, uint8_t *out);
#endif /* TETRA_INTERLEAVE_H */

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/* TETRA lower MAC layer main routine, between TP-SAP and TMV-SAP */
/* (C) 2011 by Harald Welte <laforge@gnumonks.org>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <osmocore/utils.h>
#include <tetra_common.h>
#include <tetra_tdma.h>
#include <phy/tetra_burst.h>
#include <phy/tetra_burst_sync.h>
#include <lower_mac/crc_simple.h>
#include <lower_mac/tetra_scramb.h>
#include <lower_mac/tetra_interleave.h>
#include <lower_mac/tetra_conv_enc.h>
#include <tetra_prim.h>
#include "tetra_upper_mac.h"
#include <lower_mac/viterbi.h>
struct tetra_blk_param {
const char *name;
uint16_t type345_bits;
uint16_t type2_bits;
uint16_t type1_bits;
uint16_t interleave_a;
uint8_t have_crc16;
};
/* try to aggregate all of the magic numbers somewhere central */
static const struct tetra_blk_param tetra_blk_param[] = {
[TPSAP_T_SB1] = {
.name = "SB1",
.type345_bits = 120,
.type2_bits = 80,
.type1_bits = 60,
.interleave_a = 11,
.have_crc16 = 1,
},
[TPSAP_T_SB2] = {
.name = "SB2",
.type345_bits = 216,
.type2_bits = 144,
.type1_bits = 124,
.interleave_a = 101,
.have_crc16 = 1,
},
[TPSAP_T_NDB] = {
.name = "NDB",
.type345_bits = 216,
.type2_bits = 144,
.type1_bits = 124,
.interleave_a = 101,
.have_crc16 = 1,
},
[TPSAP_T_SCH_HU] = {
.name = "SCH/HU",
.type345_bits = 168,
.type2_bits = 112,
.type1_bits = 92,
.interleave_a = 13,
.have_crc16 = 1,
},
[TPSAP_T_SCH_F] = {
.name = "SCH/F",
.type345_bits = 432,
.type2_bits = 288,
.type1_bits = 268,
.interleave_a = 103,
.have_crc16 = 1,
},
[TPSAP_T_BBK] = {
.name = "BBK",
.type345_bits = 30,
.type2_bits = 30,
.type1_bits = 14,
},
};
struct tetra_cell_data {
uint16_t mcc;
uint16_t mnc;
uint8_t colour_code;
struct tetra_tdma_time time;
uint32_t scramb_init;
};
static struct tetra_cell_data _tcd, *tcd = &_tcd;
int is_bsch(struct tetra_tdma_time *tm)
{
if (tm->fn == 18 && tm->tn == 4 - ((tm->mn+1)%4))
return 1;
return 0;
}
int is_bnch(struct tetra_tdma_time *tm)
{
if (tm->fn == 18 && tm->tn == 4 - ((tm->mn+3)%4))
return 1;
return 0;
}
struct tetra_tmvsap_prim *tmvsap_prim_alloc(uint16_t prim, uint8_t op)
{
struct tetra_tmvsap_prim *ttp;
//ttp = talloc_zero(NULL, struct tetra_tmvsap_prim);
ttp = calloc(1, sizeof(struct tetra_tmvsap_prim));
ttp->oph.sap = TETRA_SAP_TMV;
ttp->oph.primitive = prim;
ttp->oph.operation = op;
return ttp;
}
/* incoming TP-SAP UNITDATA.ind from PHY into lower MAC */
void tp_sap_udata_ind(enum tp_sap_data_type type, const uint8_t *bits, unsigned int len, void *priv)
{
/* various intermediary buffers */
uint8_t type4[512];
uint8_t type3dp[512*4];
uint8_t type3[512];
uint8_t type2[512];
const struct tetra_blk_param *tbp = &tetra_blk_param[type];
const char *time_str;
/* TMV-SAP.UNITDATA.ind primitive which we will send to the upper MAC */
struct tetra_tmvsap_prim *ttp;
struct tmv_unitdata_param *tup;
ttp = tmvsap_prim_alloc(PRIM_TMV_UNITDATA, PRIM_OP_INDICATION);
tup = &ttp->u.unitdata;
/* update the cell time */
memcpy(&tcd->time, &t_phy_state.time, sizeof(tcd->time));