libosmogsm  0.9.6.20171026
Osmocom GSM library
gsm_utils.h
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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>
33 
34 #define ADD_MODULO(sum, delta, modulo) do { \
35  if ((sum += delta) >= modulo) \
36  sum -= modulo; \
37  } while (0)
38 
39 #define GSM_MAX_FN (26*51*2048)
40 
41 /* Max length of random identifier which can be requested via osmo_get_rand_id() */
42 #define OSMO_MAX_RAND_ID_LEN 16
43 
44 struct gsm_time {
45  uint32_t fn; /* FN count */
46  uint16_t t1; /* FN div (26*51) */
47  uint8_t t2; /* FN modulo 26 */
48  uint8_t t3; /* FN modulo 51 */
49  uint8_t tc;
50 };
51 
52 enum gsm_band {
57  GSM_BAND_450 = 0x10,
58  GSM_BAND_480 = 0x20,
59  GSM_BAND_750 = 0x40,
60  GSM_BAND_810 = 0x80,
61 };
62 
63 const char *gsm_band_name(enum gsm_band band);
64 enum gsm_band gsm_band_parse(const char *mhz);
65 
66 int osmo_get_rand_id(uint8_t *out, size_t len);
67 
82 int gsm_7bit_decode_n(char *decoded, size_t n, const uint8_t *user_data, uint8_t length);
83 
89 int gsm_7bit_decode_n_ussd(char *decoded, size_t n, const uint8_t *user_data, uint8_t length);
90 
103 int gsm_7bit_encode_n(uint8_t *result, size_t n, const char *data, int *octets_written);
104 
110 int gsm_7bit_encode_n_ussd(uint8_t *result, size_t n, const char *data, int *octets_written);
111 
112 /* the four functions below are helper functions and here for the unit test */
113 int gsm_septets2octets(uint8_t *result, const uint8_t *rdata, uint8_t septet_len, uint8_t padding);
114 int gsm_septet_encode(uint8_t *result, const char *data);
115 uint8_t gsm_get_octet_len(const uint8_t sept_len);
116 int gsm_7bit_decode_n_hdr(char *decoded, size_t n, const uint8_t *user_data, uint8_t length, uint8_t ud_hdr_ind);
117 
118 unsigned int ms_class_gmsk_dbm(enum gsm_band band, int ms_class);
119 
120 int ms_pwr_ctl_lvl(enum gsm_band band, unsigned int dbm);
121 int ms_pwr_dbm(enum gsm_band band, uint8_t lvl);
122 
123 /* According to TS 05.08 Chapter 8.1.4 */
124 int rxlev2dbm(uint8_t rxlev);
125 uint8_t dbm2rxlev(int dbm);
126 
127 /* According to GSM 04.08 Chapter 10.5.1.6 */
128 static inline int ms_cm2_a5n_support(uint8_t *cm2, unsigned n) {
129  switch (n) {
130  case 0: return 1;
131  case 1: return (cm2[0] & (1<<3)) ? 0 : 1;
132  case 2: return (cm2[2] & (1<<0)) ? 1 : 0;
133  case 3: return (cm2[2] & (1<<1)) ? 1 : 0;
134  default:
135  return 0;
136  }
137 }
138 
139 /* According to GSM 04.08 Chapter 10.5.1.7 */
140 static inline int ms_cm3_a5n_support(uint8_t *cm3, unsigned n) {
141  switch (n) {
142  case 4: return (cm3[0] & (1<<0)) ? 1 : 0;
143  case 5: return (cm3[0] & (1<<1)) ? 1 : 0;
144  case 6: return (cm3[0] & (1<<2)) ? 1 : 0;
145  case 7: return (cm3[0] & (1<<3)) ? 1 : 0;
146  default:
147  return 0;
148  }
149 }
150 
151 /* According to GSM 04.08 Chapter 10.5.2.29 */
152 static inline int rach_max_trans_val2raw(int val) { return (val >> 1) & 3; }
153 static inline int rach_max_trans_raw2val(int raw) {
154  const int tbl[4] = { 1, 2, 4, 7 };
155  return tbl[raw & 3];
156 }
157 
158 #define ARFCN_PCS 0x8000
159 #define ARFCN_UPLINK 0x4000
160 #define ARFCN_FLAG_MASK 0xf000 /* Reserve the upper 5 bits for flags */
161 
162 enum gsm_band gsm_arfcn2band(uint16_t arfcn);
163 
164 /* Convert an ARFCN to the frequency in MHz * 10 */
165 uint16_t gsm_arfcn2freq10(uint16_t arfcn, int uplink);
166 
167 /* Convert a Frequency in MHz * 10 to ARFCN */
168 uint16_t gsm_freq102arfcn(uint16_t freq10, int uplink);
169 
170 /* Convert from frame number to GSM time */
171 void gsm_fn2gsmtime(struct gsm_time *time, uint32_t fn);
172 
173 /* Parse GSM Frame Number into printable string */
174 char *gsm_fn_as_gsmtime_str(uint32_t fn);
175 
176 /* Convert from GSM time to frame number */
177 uint32_t gsm_gsmtime2fn(struct gsm_time *time);
178 
179 /* Returns static buffer with string representation of a GSM Time */
180 char *osmo_dump_gsmtime(const struct gsm_time *tm);
181 
182 /* GSM TS 03.03 Chapter 2.6 */
191 };
192 
193 /* TS 03.03 Chapter 2.6 */
194 int gprs_tlli_type(uint32_t tlli);
195 
196 uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type);
197 
198 /* Osmocom internal, not part of any gsm spec */
206  GSM_PCHAN_PDCH, /* GPRS PDCH */
207  GSM_PCHAN_TCH_F_PDCH, /* TCH/F if used, PDCH otherwise */
213 };
214 
215 /* Osmocom internal, not part of any gsm spec */
226 };
227 
228 extern const struct value_string gsm_chan_t_names[];
229 
230 /* Deprectated functions */
231 /* Limit encoding and decoding to use no more than this amount of buffer bytes */
232 #define GSM_7BIT_LEGACY_MAX_BUFFER_SIZE 0x10000
233 
234 int gsm_7bit_decode(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n() instead");
235 int gsm_7bit_decode_ussd(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n_ussd() instead");
236 int gsm_7bit_encode(uint8_t *result, const char *data) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead");
237 int gsm_7bit_encode_ussd(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n_ussd() instead");
238 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.h:224
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:228
uint32_t fn
Definition: gsm_utils.h:45
Definition: gsm_utils.h:200
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:255
Definition: gsm_utils.h:201
uint32_t tlli
Definition: gsm_04_08.h:91
char * osmo_dump_gsmtime(const struct gsm_time *tm)
Definition: gsm_utils.c:824
char time[12]
Definition: ipaccess.h:838
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:170
gprs_tlli_type
Definition: gsm_utils.h:183
#define OSMO_DEPRECATED(text)
Definition: gsm_utils.h:55
Definition: gsm_utils.h:189
enum gsm_band gsm_band_parse(const char *mhz)
Parse string name of a GSM band.
Definition: gsm_utils.c:649
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:921
Definition: gsm_utils.h:225
const struct value_string gsm_chan_t_names[]
Definition: gsm48.c:392
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:934
static int ms_cm2_a5n_support(uint8_t *cm2, unsigned n)
Definition: gsm_utils.h:128
Definition: gsm_utils.h:219
uint16_t gsm_arfcn2freq10(uint16_t arfcn, int uplink)
Convert an ARFCN to the frequency in MHz * 10.
Definition: gsm_utils.c:736
uint16_t t1
Definition: gsm_utils.h:46
uint8_t type
Definition: gsm_04_08.h:91
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:612
Definition: gsm_utils.h:188
Definition: gsm_utils.h:54
Definition: gsm_utils.h:212
uint8_t tc
Definition: gsm_utils.h:49
Definition: gsm_utils.h:190
Definition: gsm_utils.h:202
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:234
uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type)
Determine TLLI from P-TMSI.
Definition: gsm_utils.c:893
Definition: gsm_utils.h:220
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:940
Definition: gsm_utils.h:218
Definition: gsm_utils.h:58
int gsm_7bit_encode(uint8_t *result, const char *data) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead")
Definition: gsm_utils.c:927
const char * gsm_band_name(enum gsm_band band)
Return string name of a given GSM Band.
Definition: gsm_utils.c:625
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:289
Definition: gsm_utils.h:60
Definition: gsm_utils.h:223
gsm_phys_chan_config
Definition: gsm_utils.h:199
Definition: gsm_utils.h:206
uint8_t t3
Definition: gsm_utils.h:48
static int ms_cm3_a5n_support(uint8_t *cm3, unsigned n)
Definition: gsm_utils.h:140
static int rach_max_trans_raw2val(int raw)
Definition: gsm_utils.h:153
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:463
Definition: gsm_utils.h:211
uint8_t cm3
Definition: gsm_04_08.h:103
Definition: gsm_utils.h:57
Definition: gsm_utils.h:222
Definition: gsm_utils.h:59
struct gsm48_classmark2 cm2
Definition: gsm_04_08.h:92
Definition: gsm_utils.h:210
Definition: gsm_utils.h:44
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:912
int rxlev2dbm(uint8_t rxlev)
Convert TS 05.08 RxLev to dBm (TS 05.08 Chapter 8.1.4)
Definition: gsm_utils.c:601
static int rach_max_trans_val2raw(int val)
Definition: gsm_utils.h:152
uint8_t len
Definition: gsm_04_11.h:434
Definition: gsm_utils.h:209
Definition: gsm_utils.h:205
uint16_t gsm_freq102arfcn(uint16_t freq10, int uplink)
Convert a Frequency in MHz * 10 to ARFCN.
Definition: gsm_utils.c:763
Definition: gsm_utils.h:217
uint32_t gsm_gsmtime2fn(struct gsm_time *time)
Encode decoded gsm_time to Frame Number.
Definition: gsm_utils.c:818
uint8_t t2
Definition: gsm_utils.h:47
Definition: gsm_utils.h:187
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:683
Definition: gsm_utils.h:221
Definition: gsm_utils.h:56
gsm_chan_t
Definition: gsm_utils.h:216
Definition: gsm_utils.h:208
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:508
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:410
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:384
gsm_band
Definition: gsm_utils.h:52
Definition: gsm_utils.h:184
Definition: gsm_utils.h:185
char * gsm_fn_as_gsmtime_str(uint32_t fn)
Parse GSM Frame Number into printable string.
Definition: gsm_utils.c:807
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:155
Definition: gsm_utils.h:204
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:560
void gsm_fn2gsmtime(struct gsm_time *time, uint32_t fn)
Parse GSM Frame Number into struct gsm_time.
Definition: gsm_utils.c:795
Definition: gsm_utils.h:53
Definition: gsm_utils.h:186
uint8_t length
Definition: gsm_08_08.h:453
uint8_t data[0]
message payload data
Definition: gsm_03_41.h:108
Definition: gsm_utils.h:207
Definition: gsm_utils.h:203
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:340