libosmogsm  0.12.0
Osmocom GSM library
gsm_utils.h
Go to the documentation of this file.
1 
3 /*
4  * (C) 2008 by Daniel Willmann <daniel@totalueberwachung.de>
5  * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
6  * (C) 2009-2010 by Harald Welte <laforge@gnumonks.org>
7  *
8  * All Rights Reserved
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License along
21  * with this program; if not, write to the Free Software Foundation, Inc.,
22  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
23  *
24  */
25 
26 #pragma once
27 
28 #include <stddef.h>
29 #include <stdint.h>
30 
31 #include <osmocom/core/defs.h>
32 #include <osmocom/core/utils.h>
35 
36 #define ADD_MODULO(sum, delta, modulo) do { \
37  if ((sum += delta) >= modulo) \
38  sum -= modulo; \
39  } while (0)
40 
41 #define GSM_MAX_FN (26*51*2048)
42 
43 /* Max length of random identifier which can be requested via osmo_get_rand_id() */
44 #define OSMO_MAX_RAND_ID_LEN 16
45 
46 struct gsm_time {
47  uint32_t fn; /* FN count */
48  uint16_t t1; /* FN div (26*51) */
49  uint8_t t2; /* FN modulo 26 */
50  uint8_t t3; /* FN modulo 51 */
51  uint8_t tc;
52 };
53 
54 enum gsm_band {
59  GSM_BAND_450 = 0x10,
60  GSM_BAND_480 = 0x20,
61  GSM_BAND_750 = 0x40,
62  GSM_BAND_810 = 0x80,
63 };
64 
65 const char *gsm_band_name(enum gsm_band band);
66 enum gsm_band gsm_band_parse(const char *mhz);
67 
68 int osmo_get_rand_id(uint8_t *out, size_t len);
69 
84 int gsm_7bit_decode_n(char *decoded, size_t n, const uint8_t *user_data, uint8_t length);
85 
91 int gsm_7bit_decode_n_ussd(char *decoded, size_t n, const uint8_t *user_data, uint8_t length);
92 
105 int gsm_7bit_encode_n(uint8_t *result, size_t n, const char *data, int *octets_written);
106 
112 int gsm_7bit_encode_n_ussd(uint8_t *result, size_t n, const char *data, int *octets_written);
113 
114 /* the four functions below are helper functions and here for the unit test */
115 int gsm_septets2octets(uint8_t *result, const uint8_t *rdata, uint8_t septet_len, uint8_t padding);
116 int gsm_septet_encode(uint8_t *result, const char *data);
117 uint8_t gsm_get_octet_len(const uint8_t sept_len);
118 int gsm_7bit_decode_n_hdr(char *decoded, size_t n, const uint8_t *user_data, uint8_t length, uint8_t ud_hdr_ind);
119 
120 unsigned int ms_class_gmsk_dbm(enum gsm_band band, int ms_class);
121 
122 int ms_pwr_ctl_lvl(enum gsm_band band, unsigned int dbm);
123 int ms_pwr_dbm(enum gsm_band band, uint8_t lvl);
124 
125 /* According to TS 05.08 Chapter 8.1.4 */
126 int rxlev2dbm(uint8_t rxlev);
127 uint8_t dbm2rxlev(int dbm);
128 
129 /* According to GSM 04.08 Chapter 10.5.1.6 */
130 static inline int ms_cm2_a5n_support(uint8_t *cm2, unsigned n) {
131  switch (n) {
132  case 0: return 1;
133  case 1: return (cm2[0] & (1<<3)) ? 0 : 1;
134  case 2: return (cm2[2] & (1<<0)) ? 1 : 0;
135  case 3: return (cm2[2] & (1<<1)) ? 1 : 0;
136  default:
137  return 0;
138  }
139 }
140 
141 /* According to GSM 04.08 Chapter 10.5.1.7 */
142 static inline int ms_cm3_a5n_support(uint8_t *cm3, unsigned n) {
143  switch (n) {
144  case 4: return (cm3[0] & (1<<0)) ? 1 : 0;
145  case 5: return (cm3[0] & (1<<1)) ? 1 : 0;
146  case 6: return (cm3[0] & (1<<2)) ? 1 : 0;
147  case 7: return (cm3[0] & (1<<3)) ? 1 : 0;
148  default:
149  return 0;
150  }
151 }
152 
153 /* According to GSM 04.08 Chapter 10.5.2.29 */
154 static inline int rach_max_trans_val2raw(int val) { return (val >> 1) & 3; }
155 static inline int rach_max_trans_raw2val(int raw) {
156  const int tbl[4] = { 1, 2, 4, 7 };
157  return tbl[raw & 3];
158 }
159 
160 #define ARFCN_PCS 0x8000
161 #define ARFCN_UPLINK 0x4000
162 #define ARFCN_FLAG_MASK 0xf000 /* Reserve the upper 5 bits for flags */
163 
164 enum gsm_band gsm_arfcn2band(uint16_t arfcn);
165 
166 /* Convert an ARFCN to the frequency in MHz * 10 */
167 uint16_t gsm_arfcn2freq10(uint16_t arfcn, int uplink);
168 
169 /* Convert a Frequency in MHz * 10 to ARFCN */
170 uint16_t gsm_freq102arfcn(uint16_t freq10, int uplink);
171 
172 /* Convert from frame number to GSM time */
173 void gsm_fn2gsmtime(struct gsm_time *time, uint32_t fn);
174 
175 /* Parse GSM Frame Number into printable string */
176 char *gsm_fn_as_gsmtime_str(uint32_t fn);
177 
178 /* Convert from GSM time to frame number */
179 uint32_t gsm_gsmtime2fn(struct gsm_time *time);
180 
181 /* Returns static buffer with string representation of a GSM Time */
182 char *osmo_dump_gsmtime(const struct gsm_time *tm);
183 
184 /* GSM TS 03.03 Chapter 2.6 */
193 };
194 
195 /* TS 03.03 Chapter 2.6 */
196 int gprs_tlli_type(uint32_t tlli);
197 
198 uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type);
199 
200 /* Osmocom internal, not part of any gsm spec */
208  GSM_PCHAN_PDCH, /* GPRS PDCH */
209  GSM_PCHAN_TCH_F_PDCH, /* TCH/F if used, PDCH otherwise */
215 };
216 
217 /* Osmocom internal, not part of any gsm spec */
228 };
229 
230 extern const struct value_string gsm_chan_t_names[];
231 
232 /* Deprectated functions */
233 /* Limit encoding and decoding to use no more than this amount of buffer bytes */
234 #define GSM_7BIT_LEGACY_MAX_BUFFER_SIZE 0x10000
235 
236 int gsm_7bit_decode(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n() instead");
237 int gsm_7bit_decode_ussd(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n_ussd() instead");
238 int gsm_7bit_encode(uint8_t *result, const char *data) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead");
239 int gsm_7bit_encode_ussd(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n_ussd() instead");
240 int gsm_7bit_encode_oct(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead");
len
uint8_t len
Definition: gsm_04_11.h:2
data
uint8_t data[0]
message payload data
Definition: gsm_03_41.h:34
GSM_PCHAN_TCH_H
@ GSM_PCHAN_TCH_H
Definition: gsm_utils.h:206
gsm_chan_t
gsm_chan_t
Definition: gsm_utils.h:218
GSM_PCHAN_UNKNOWN
@ GSM_PCHAN_UNKNOWN
Definition: gsm_utils.h:210
dbm2rxlev
uint8_t dbm2rxlev(int dbm)
Convert RF signal level in dBm to TS 05.08 RxLev (TS 05.08 Chapter 8.1.4)
Definition: gsm_utils.c:642
time
char time[12]
Definition: ipaccess.h:9
gsm_7bit_encode
int gsm_7bit_encode(uint8_t *result, const char *data) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead")
Definition: gsm_utils.c:957
gsm_7bit_encode_n_ussd
int gsm_7bit_encode_n_ussd(uint8_t *result, size_t n, const char *data, int *octets_written)
Encode a text string into GSM 03.38 encoded 7 bit characters (USSD encoding).
Definition: gsm_utils.c:411
gsm_band_name
const char * gsm_band_name(enum gsm_band band)
Return string name of a given GSM Band.
Definition: gsm_utils.c:655
gsm_arfcn2band
enum gsm_band gsm_arfcn2band(uint16_t arfcn)
Resolve GSM band from ARFCN In Osmocom, we use the highest bit of the arfcn to indicate PCS.
Definition: gsm_utils.c:713
gsm_time::tc
uint8_t tc
Definition: gsm_utils.h:51
gsm_time
Definition: gsm_utils.h:46
gsm_band
gsm_band
Definition: gsm_utils.h:54
gsm_septet_encode
int gsm_septet_encode(uint8_t *result, const char *data)
Encode a ASCII characterrs as 7-bit GSM alphabet (TS 03.38)
Definition: gsm_utils.c:282
gsm_fn2gsmtime
void gsm_fn2gsmtime(struct gsm_time *time, uint32_t fn)
Parse GSM Frame Number into struct gsm_time.
Definition: gsm_utils.c:825
gsm_7bit_encode_oct
int gsm_7bit_encode_oct(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead")
Definition: gsm_utils.c:970
cm3
uint8_t cm3
Definition: gsm_04_08.h:38
GSM_BAND_810
@ GSM_BAND_810
Definition: gsm_utils.h:62
gsm_gsmtime2fn
uint32_t gsm_gsmtime2fn(struct gsm_time *time)
Encode decoded gsm_time to Frame Number.
Definition: gsm_utils.c:848
TLLI_G_RNTI
@ TLLI_G_RNTI
Definition: gsm_utils.h:191
GSM_LCHAN_TCH_H
@ GSM_LCHAN_TCH_H
Definition: gsm_utils.h:222
GSM_PCHAN_TCH_F
@ GSM_PCHAN_TCH_F
Definition: gsm_utils.h:205
rxlev2dbm
int rxlev2dbm(uint8_t rxlev)
Convert TS 05.08 RxLev to dBm (TS 05.08 Chapter 8.1.4)
Definition: gsm_utils.c:631
ms_cm3_a5n_support
static int ms_cm3_a5n_support(uint8_t *cm3, unsigned n)
Definition: gsm_utils.h:142
GSM_LCHAN_CBCH
@ GSM_LCHAN_CBCH
Definition: gsm_utils.h:226
ms_pwr_ctl_lvl
int ms_pwr_ctl_lvl(enum gsm_band band, unsigned int dbm)
determine power control level for given dBm value, as indicated by the tables in chapter 4....
Definition: gsm_utils.c:538
GSM_BAND_480
@ GSM_BAND_480
Definition: gsm_utils.h:60
gsm_arfcn2freq10
uint16_t gsm_arfcn2freq10(uint16_t arfcn, int uplink)
Convert an ARFCN to the frequency in MHz * 10.
Definition: gsm_utils.c:766
GSM_PCHAN_CCCH
@ GSM_PCHAN_CCCH
Definition: gsm_utils.h:203
length
uint8_t length
Definition: gsm_08_08.h:3
GSM_LCHAN_PDTCH
@ GSM_LCHAN_PDTCH
Definition: gsm_utils.h:225
GSM_BAND_450
@ GSM_BAND_450
Definition: gsm_utils.h:59
gsm_7bit_decode
int gsm_7bit_decode(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n() instead")
Definition: gsm_utils.c:942
gsm_7bit_decode_n_hdr
int gsm_7bit_decode_n_hdr(char *decoded, size_t n, const uint8_t *user_data, uint8_t length, uint8_t ud_hdr_ind)
TS 03.38 7-bit Character unpacking (6.2.1)
Definition: gsm_utils.c:197
GSM_PCHAN_PDCH
@ GSM_PCHAN_PDCH
Definition: gsm_utils.h:208
gsm_time::t3
uint8_t t3
Definition: gsm_utils.h:50
GSM_LCHAN_TCH_F
@ GSM_LCHAN_TCH_F
Definition: gsm_utils.h:221
gsm_band_parse
enum gsm_band gsm_band_parse(const char *mhz)
Parse string name of a GSM band.
Definition: gsm_utils.c:679
gsm_chan_t_names
const struct value_string gsm_chan_t_names[]
Definition: gsm48.c:409
GSM_LCHAN_CCCH
@ GSM_LCHAN_CCCH
Definition: gsm_utils.h:224
gsm_freq102arfcn
uint16_t gsm_freq102arfcn(uint16_t freq10, int uplink)
Convert a Frequency in MHz * 10 to ARFCN.
Definition: gsm_utils.c:793
GSM_PCHAN_SDCCH8_SACCH8C_CBCH
@ GSM_PCHAN_SDCCH8_SACCH8C_CBCH
Definition: gsm_utils.h:212
GSM_LCHAN_NONE
@ GSM_LCHAN_NONE
Definition: gsm_utils.h:219
TLLI_RESERVED
@ TLLI_RESERVED
Definition: gsm_utils.h:190
GSM_BAND_900
@ GSM_BAND_900
Definition: gsm_utils.h:56
_GSM_PCHAN_MAX
@ _GSM_PCHAN_MAX
Definition: gsm_utils.h:214
TLLI_AUXILIARY
@ TLLI_AUXILIARY
Definition: gsm_utils.h:189
gsm_time::t1
uint16_t t1
Definition: gsm_utils.h:48
GSM_BAND_1900
@ GSM_BAND_1900
Definition: gsm_utils.h:58
type
uint8_t type
Definition: gsm_04_08.h:713
ms_class_gmsk_dbm
unsigned int ms_class_gmsk_dbm(enum gsm_band band, int ms_class)
Convert power class to dBm according to GSM TS 05.05.
Definition: gsm_utils.c:493
ms_pwr_dbm
int ms_pwr_dbm(enum gsm_band band, uint8_t lvl)
Convert TS 05.05 power level to absolute dBm value.
Definition: gsm_utils.c:590
GSM_PCHAN_CCCH_SDCCH4_CBCH
@ GSM_PCHAN_CCCH_SDCCH4_CBCH
Definition: gsm_utils.h:211
GSM_PCHAN_CCCH_SDCCH4
@ GSM_PCHAN_CCCH_SDCCH4
Definition: gsm_utils.h:204
gsm_04_08.h
TLLI_LOCAL
@ TLLI_LOCAL
Definition: gsm_utils.h:186
GSM_LCHAN_SDCCH
@ GSM_LCHAN_SDCCH
Definition: gsm_utils.h:220
TLLI_RAND_G_RNTI
@ TLLI_RAND_G_RNTI
Definition: gsm_utils.h:192
GSM_LCHAN_UNKNOWN
@ GSM_LCHAN_UNKNOWN
Definition: gsm_utils.h:223
osmo_get_rand_id
int osmo_get_rand_id(uint8_t *out, size_t len)
Generate random identifier We use /dev/urandom (default when GRND_RANDOM flag is not set).
Definition: gsm_utils.c:437
osmo_dump_gsmtime
char * osmo_dump_gsmtime(const struct gsm_time *tm)
Definition: gsm_utils.c:854
GSM_BAND_850
@ GSM_BAND_850
Definition: gsm_utils.h:55
gsm_get_octet_len
uint8_t gsm_get_octet_len(const uint8_t sept_len)
\brife Compute number of octets from number of septets, for instance: 47 septets needs 41,...
Definition: gsm_utils.c:182
gprs_tlli_type
gprs_tlli_type
Definition: gsm_utils.h:185
rach_max_trans_raw2val
static int rach_max_trans_raw2val(int raw)
Definition: gsm_utils.h:155
rach_max_trans_val2raw
static int rach_max_trans_val2raw(int val)
Definition: gsm_utils.h:154
gsm_7bit_decode_n
int gsm_7bit_decode_n(char *decoded, size_t n, const uint8_t *user_data, uint8_t length)
Decode a sequence of GSM 03.38 encoded 7 bit characters.
Definition: gsm_utils.c:255
GSM_PCHAN_TCH_F_TCH_H_PDCH
@ GSM_PCHAN_TCH_F_TCH_H_PDCH
Definition: gsm_utils.h:213
gsm_phys_chan_config
gsm_phys_chan_config
Definition: gsm_utils.h:201
gsm_08_08.h
gsm_7bit_decode_n_ussd
int gsm_7bit_decode_n_ussd(char *decoded, size_t n, const uint8_t *user_data, uint8_t length)
Decode a sequence of 7 bit characters (USSD encoding).
Definition: gsm_utils.c:261
TLLI_RANDOM
@ TLLI_RANDOM
Definition: gsm_utils.h:188
gsm_time::t2
uint8_t t2
Definition: gsm_utils.h:49
gsm_7bit_encode_n
int gsm_7bit_encode_n(uint8_t *result, size_t n, const char *data, int *octets_written)
Encode a text string into GSM 03.38 encoded 7 bit characters.
Definition: gsm_utils.c:367
GSM_PCHAN_TCH_F_PDCH
@ GSM_PCHAN_TCH_F_PDCH
Definition: gsm_utils.h:209
gsm_time::fn
uint32_t fn
Definition: gsm_utils.h:47
GSM_BAND_750
@ GSM_BAND_750
Definition: gsm_utils.h:61
gsm_septets2octets
int gsm_septets2octets(uint8_t *result, const uint8_t *rdata, uint8_t septet_len, uint8_t padding)
GSM Default Alphabet 7bit to octet packing.
Definition: gsm_utils.c:316
ms_cm2_a5n_support
static int ms_cm2_a5n_support(uint8_t *cm2, unsigned n)
Definition: gsm_utils.h:130
GSM_PCHAN_SDCCH8_SACCH8C
@ GSM_PCHAN_SDCCH8_SACCH8C
Definition: gsm_utils.h:207
cm2
struct gsm48_classmark2 cm2
Definition: gsm_04_08.h:709
GSM_PCHAN_NONE
@ GSM_PCHAN_NONE
Definition: gsm_utils.h:202
gsm_fn_as_gsmtime_str
char * gsm_fn_as_gsmtime_str(uint32_t fn)
Parse GSM Frame Number into printable string.
Definition: gsm_utils.c:837
gprs_tmsi2tlli
uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type)
Determine TLLI from P-TMSI.
Definition: gsm_utils.c:923
GSM_BAND_1800
@ GSM_BAND_1800
Definition: gsm_utils.h:57
gsm_7bit_decode_ussd
int gsm_7bit_decode_ussd(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n_ussd() instead")
Definition: gsm_utils.c:951
tlli
uint32_t tlli
Definition: gsm_04_08.h:708
_GSM_LCHAN_MAX
@ _GSM_LCHAN_MAX
Definition: gsm_utils.h:227
TLLI_FOREIGN
@ TLLI_FOREIGN
Definition: gsm_utils.h:187
gsm_7bit_encode_ussd
int gsm_7bit_encode_ussd(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n_ussd() instead")
Definition: gsm_utils.c:964