libosmogsm  1.0.1
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 int gsm_arfcn2band_rc(uint16_t arfcn, enum gsm_band *band);
165 enum gsm_band gsm_arfcn2band(uint16_t arfcn) OSMO_DEPRECATED("Use gsm_arfcn2band_rc() instead");
166 
167 /* Convert an ARFCN to the frequency in MHz * 10 */
168 uint16_t gsm_arfcn2freq10(uint16_t arfcn, int uplink);
169 
170 /* Convert a Frequency in MHz * 10 to ARFCN */
171 uint16_t gsm_freq102arfcn(uint16_t freq10, int uplink);
172 
173 /* Convert from frame number to GSM time */
174 void gsm_fn2gsmtime(struct gsm_time *time, uint32_t fn);
175 
176 /* Parse GSM Frame Number into printable string */
177 char *gsm_fn_as_gsmtime_str(uint32_t fn);
178 
179 /* Convert from GSM time to frame number */
180 uint32_t gsm_gsmtime2fn(struct gsm_time *time);
181 
182 /* Returns static buffer with string representation of a GSM Time */
183 char *osmo_dump_gsmtime(const struct gsm_time *tm);
184 
185 /* GSM TS 03.03 Chapter 2.6 */
194 };
195 
196 /* TS 03.03 Chapter 2.6 */
197 int gprs_tlli_type(uint32_t tlli);
198 
199 uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type);
200 
201 /* Osmocom internal, not part of any gsm spec */
209  GSM_PCHAN_PDCH, /* GPRS PDCH */
210  GSM_PCHAN_TCH_F_PDCH, /* TCH/F if used, PDCH otherwise */
216 };
217 
218 /* Osmocom internal, not part of any gsm spec */
229 };
230 
231 extern const struct value_string gsm_chan_t_names[];
232 static inline const char *gsm_chan_t_name(enum gsm48_chan_mode val)
233 { return get_value_string(gsm_chan_t_names, val); }
234 
235 /* Deprectated functions */
236 /* Limit encoding and decoding to use no more than this amount of buffer bytes */
237 #define GSM_7BIT_LEGACY_MAX_BUFFER_SIZE 0x10000
238 
239 int gsm_7bit_decode(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n() instead");
240 int gsm_7bit_decode_ussd(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n_ussd() instead");
241 int gsm_7bit_encode(uint8_t *result, const char *data) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead");
242 int gsm_7bit_encode_ussd(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n_ussd() instead");
243 int gsm_7bit_encode_oct(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead");
244 
250 
251  /* keep this last */
253 };
254 
255 extern const struct value_string osmo_rat_type_names[];
256 inline static const char *osmo_rat_type_name(enum osmo_rat_type val)
257 { return get_value_string(osmo_rat_type_names, val); }
Definition: gsm_utils.h:227
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:260
uint32_t fn
Definition: gsm_utils.h:47
Definition: gsm_utils.h:203
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:287
Definition: gsm_utils.h:204
uint32_t tlli
Definition: gsm_04_08.h:805
char * osmo_dump_gsmtime(const struct gsm_time *tm)
Definition: gsm_utils.c:884
Definition: gsm_utils.h:249
uint8_t type
Definition: gsm_08_08.h:469
char time[12]
Definition: ipaccess.h:160
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:202
gprs_tlli_type
Definition: gsm_utils.h:186
#define OSMO_DEPRECATED(text)
Definition: gsm_utils.h:57
Definition: gsm_utils.h:192
gsm48_chan_mode
Definition: gsm_04_08.h:792
enum gsm_band gsm_band_parse(const char *mhz)
Parse string name of a GSM band.
Definition: gsm_utils.c:684
const char * get_value_string(const struct value_string *vs, uint32_t val)
static const char * osmo_rat_type_name(enum osmo_rat_type val)
Definition: gsm_utils.h:256
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:981
Definition: gsm_utils.h:228
const struct value_string gsm_chan_t_names[]
Definition: gsm48.c:409
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:994
static int ms_cm2_a5n_support(uint8_t *cm2, unsigned n)
Definition: gsm_utils.h:130
enum gsm_band gsm_arfcn2band(uint16_t arfcn) OSMO_DEPRECATED("Use gsm_arfcn2band_rc() instead")
Resolve GSM band from ARFCN, aborts process on invalid ARFCN.
Definition: gsm_utils.c:761
Definition: gsm_utils.h:222
uint16_t gsm_arfcn2freq10(uint16_t arfcn, int uplink)
Convert an ARFCN to the frequency in MHz * 10.
Definition: gsm_utils.c:796
uint16_t t1
Definition: gsm_utils.h:48
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:647
static const char * gsm_chan_t_name(enum gsm48_chan_mode val)
Definition: gsm_utils.h:232
Definition: gsm_utils.h:252
Definition: gsm_utils.h:191
Definition: gsm_utils.h:56
Definition: gsm_utils.h:215
uint8_t tc
Definition: gsm_utils.h:51
Definition: gsm_utils.h:193
int gsm_arfcn2band_rc(uint16_t arfcn, enum gsm_band *band)
Resolve GSM band from ARFCN.
Definition: gsm_utils.c:719
Definition: gsm_utils.h:205
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:266
uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type)
Determine TLLI from P-TMSI.
Definition: gsm_utils.c:953
Definition: gsm_utils.h:223
GSM TS 04.08 definitions.
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:1000
Definition: gsm_utils.h:221
Definition: gsm_utils.h:60
int gsm_7bit_encode(uint8_t *result, const char *data) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead")
Definition: gsm_utils.c:987
const char * gsm_band_name(enum gsm_band band)
Return string name of a given GSM Band.
Definition: gsm_utils.c:660
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:321
Definition: gsm_utils.h:62
Definition: gsm_utils.h:226
gsm_phys_chan_config
Definition: gsm_utils.h:202
Definition: gsm_utils.h:209
uint8_t t3
Definition: gsm_utils.h:50
static int ms_cm3_a5n_support(uint8_t *cm3, unsigned n)
Definition: gsm_utils.h:142
static int rach_max_trans_raw2val(int raw)
Definition: gsm_utils.h:155
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:498
Definition: gsm_utils.h:214
Definition: gsm_utils.h:246
Definition: gsm_utils.h:59
Definition: gsm_utils.h:225
Definition: gsm_utils.h:61
struct gsm48_classmark2 cm2
Definition: gsm_04_08.h:806
Definition: gsm_utils.h:213
osmo_rat_type
Definition: gsm_utils.h:245
Definition: gsm_utils.h:46
Definition: gsm_utils.h:247
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:972
int rxlev2dbm(uint8_t rxlev)
Convert TS 05.08 RxLev to dBm (TS 05.08 Chapter 8.1.4)
Definition: gsm_utils.c:636
static int rach_max_trans_val2raw(int val)
Definition: gsm_utils.h:154
uint8_t len
Definition: gsm_04_11.h:465
Definition: gsm_utils.h:212
Definition: gsm_utils.h:208
uint16_t gsm_freq102arfcn(uint16_t freq10, int uplink)
Convert a Frequency in MHz * 10 to ARFCN.
Definition: gsm_utils.c:823
Definition: gsm_utils.h:220
uint32_t gsm_gsmtime2fn(struct gsm_time *time)
Encode decoded gsm_time to Frame Number.
Definition: gsm_utils.c:878
uint8_t t2
Definition: gsm_utils.h:49
Definition: gsm_utils.h:190
Definition: gsm_utils.h:224
Definition: gsm_utils.h:58
Definition: gsm_utils.h:248
gsm_chan_t
Definition: gsm_utils.h:219
Definition: gsm_utils.h:211
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:543
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:442
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:416
gsm_band
Definition: gsm_utils.h:54
Definition: gsm_utils.h:187
Definition: gsm_utils.h:188
char * gsm_fn_as_gsmtime_str(uint32_t fn)
Parse GSM Frame Number into printable string.
Definition: gsm_utils.c:867
uint8_t gsm_get_octet_len(const uint8_t sept_len)
Compute number of octets from number of septets, for instance: 47 septets needs 41,125 = 42 octets
Definition: gsm_utils.c:187
const struct value_string osmo_rat_type_names[]
Definition: gsm_utils.c:1007
Definition: gsm_utils.h:207
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:595
void gsm_fn2gsmtime(struct gsm_time *time, uint32_t fn)
Parse GSM Frame Number into struct gsm_time.
Definition: gsm_utils.c:855
Definition: gsm_utils.h:55
Definition: gsm_utils.h:189
uint8_t length
Definition: gsm_08_08.h:470
uint8_t data[0]
message payload data
Definition: gsm_03_41.h:89
Definition: gsm_utils.h:210
Definition: gsm_utils.h:206
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:372