2 * (C) 2008 by Daniel Willmann <daniel@totalueberwachung.de>
3 * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
4 * (C) 2009-2010 by Harald Welte <laforge@gnumonks.org>
5 * (C) 2010 by Nico Golde <nico@ngolde.de>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
25 //#include <openbsc/gsm_data.h>
26 #include <osmocom/core/utils.h>
27 #include <osmocom/gsm/gsm_utils.h>
36 #include "../../config.h"
38 /* ETSI GSM 03.38 6.2.1 and 6.2.1.1 default alphabet
39 * Greek symbols at hex positions 0x10 and 0x12-0x1a
40 * left out as they can't be handled with a char and
41 * since most phones don't display or write these
42 * characters this would only needlessly make the code
45 static unsigned char gsm_7bit_alphabet[] = {
46 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x0a, 0xff, 0xff, 0x0d, 0xff,
47 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
48 0xff, 0xff, 0x20, 0x21, 0x22, 0x23, 0x02, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c,
49 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b,
50 0x3c, 0x3d, 0x3e, 0x3f, 0x00, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a,
51 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
52 0x5a, 0x3c, 0x2f, 0x3e, 0x14, 0x11, 0xff, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
53 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
54 0x78, 0x79, 0x7a, 0x28, 0x40, 0x29, 0x3d, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
55 0xff, 0xff, 0x0c, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x5e, 0xff, 0xff,
56 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x40, 0xff, 0x01, 0xff,
57 0x03, 0xff, 0x7b, 0x7d, 0xff, 0xff, 0xff, 0xff, 0xff, 0x5c, 0xff, 0xff, 0xff, 0xff, 0xff,
58 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x5b, 0x7e, 0x5d, 0xff, 0x7c, 0xff, 0xff, 0xff,
59 0xff, 0x5b, 0x0e, 0x1c, 0x09, 0xff, 0x1f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x5d,
60 0xff, 0xff, 0xff, 0xff, 0x5c, 0xff, 0x0b, 0xff, 0xff, 0xff, 0x5e, 0xff, 0xff, 0x1e, 0x7f,
61 0xff, 0xff, 0xff, 0x7b, 0x0f, 0x1d, 0xff, 0x04, 0x05, 0xff, 0xff, 0x07, 0xff, 0xff, 0xff,
62 0xff, 0x7d, 0x08, 0xff, 0xff, 0xff, 0x7c, 0xff, 0x0c, 0x06, 0xff, 0xff, 0x7e, 0xff, 0xff
65 /* GSM 03.38 6.2.1 Character lookup for decoding */
66 static int gsm_septet_lookup(uint8_t ch)
69 for(; i < sizeof(gsm_7bit_alphabet); i++){
70 if(gsm_7bit_alphabet[i] == ch)
76 /* Compute the number of octets from the number of septets, for instance: 47 septets needs 41,125 = 42 octets */
77 uint8_t gsm_get_octet_len(const uint8_t sept_len){
78 int octet_len = (sept_len * 7) / 8;
79 if ((sept_len * 7) % 8 != 0)
85 /* GSM 03.38 6.2.1 Character unpacking */
86 int gsm_7bit_decode_hdr(char *text, const uint8_t *user_data, uint8_t septet_l, uint8_t ud_hdr_ind)
91 uint8_t *rtext = calloc(septet_l, sizeof(uint8_t));
94 /* skip the user data header */
96 /* get user data header length + 1 (for the 'user data header length'-field) */
97 shift = ((user_data[0] + 1) * 8) / 7;
98 if ((((user_data[0] + 1) * 8) % 7) != 0)
100 septet_l = septet_l - shift;
103 for (i = 0; i < septet_l; i++) {
105 ((user_data[((i + shift) * 7 + 7) >> 3] <<
106 (7 - (((i + shift) * 7 + 7) & 7))) |
107 (user_data[((i + shift) * 7) >> 3] >>
108 (((i + shift) * 7) & 7))) & 0x7f;
111 for(i = 0; i < septet_l; i++){
112 /* this is an extension character */
113 if(rtext[i] == 0x1b && i + 1 < septet_l){
115 *(text++) = gsm_7bit_alphabet[0x7f + tmp];
120 *(text++) = gsm_septet_lookup(rtext[i]);
131 int gsm_7bit_decode(char *text, const uint8_t *user_data, uint8_t septet_l)
133 return gsm_7bit_decode_hdr(text, user_data, septet_l, 0);
136 /* GSM 03.38 6.2.1 Prepare character packing */
137 int gsm_septet_encode(uint8_t *result, const char *data)
141 for(i = 0; i < strlen(data); i++){
144 /* fall-through for extension characters */
156 result[y] = gsm_7bit_alphabet[ch];
165 /* 7bit to octet packing */
166 int gsm_septets2octets(uint8_t *result, uint8_t *rdata, uint8_t septet_len, uint8_t padding){
170 uint8_t *data = calloc(septet_len + 1, sizeof(uint8_t));
174 /* the first zero is needed for padding */
175 memcpy(data + 1, rdata, septet_len);
178 memcpy(data, rdata, septet_len);
180 for(i = 0; i < septet_len; i++) {
183 * special end case with the. This is necessary if the
184 * last septet fits into the previous octet. E.g. 48
185 * non-extension characters:
186 * ....ag ( a = 1100001, g = 1100111)
187 * result[40] = 100001 XX, result[41] = 1100111 1 */
188 if (i + 1 < septet_len) {
191 } else if (i + 1 == septet_len)
195 cb = (data[i] & 0x7f) >> shift;
196 if (i + 1 < septet_len) {
197 nb = (data[i + 1] & 0x7f) << (7 - shift);
210 /* GSM 03.38 6.2.1 Character packing */
211 int gsm_7bit_encode(uint8_t *result, const char *data)
214 /* prepare for the worst case, every character expanding to two bytes */
215 uint8_t *rdata = calloc(strlen(data) * 2, sizeof(uint8_t));
216 y = gsm_septet_encode(rdata, data);
217 z = gsm_septets2octets(result, rdata, y, 0);
222 * We don't care about the number of octets (z), because they are not
224 * 1.) 46 non-extension characters + 1 extension character
225 * => (46 * 7 bit + (1 * (2 * 7 bit))) / 8 bit = 42 octets
226 * 2.) 47 non-extension characters
227 * => (47 * 7 bit) / 8 bit = 41,125 = 42 octets
228 * 3.) 48 non-extension characters
229 * => (48 * 7 bit) / 8 bit = 42 octects
234 /* convert power class to dBm according to GSM TS 05.05 */
235 unsigned int ms_class_gmsk_dbm(enum gsm_band band, int class)
253 return 29; /* 0.8W */
259 return 24; /* 0.25W */
267 return 24; /* 0.25W */
275 /* determine power control level for given dBm value, as indicated
276 * by the tables in chapter 4.1.1 of GSM TS 05.05 */
277 int ms_pwr_ctl_lvl(enum gsm_band band, unsigned int dbm)
291 /* we are guaranteed to have (5 <= dbm < 39) */
292 return 2 + ((39 - dbm) / 2);
305 /* we are guaranteed to have (0 <= dbm < 31) */
306 return (30 - dbm) / 2;
317 /* we are guaranteed to have (0 <= dbm < 31) */
318 return (30 - dbm) / 2;
325 int ms_pwr_dbm(enum gsm_band band, uint8_t lvl)
339 return 39 - ((lvl - 2) * 2) ;
345 return 30 - (lvl * 2);
349 return 36 - ((lvl - 29) * 2);
353 return 30 - (lvl * 2);
357 return 33 - (lvl - 30);
363 /* According to TS 08.05 Chapter 8.1.4 */
364 int rxlev2dbm(uint8_t rxlev)
372 /* According to TS 08.05 Chapter 8.1.4 */
373 uint8_t dbm2rxlev(int dbm)
375 int rxlev = dbm + 110;
385 const char *gsm_band_name(enum gsm_band band)
408 enum gsm_band gsm_band_parse(const char* mhz)
410 while (*mhz && !isdigit(*mhz))
416 switch (strtol(mhz, NULL, 10)) {
430 return GSM_BAND_1800;
432 return GSM_BAND_1900;
438 enum gsm_band gsm_arfcn2band(uint16_t arfcn)
440 int is_pcs = arfcn & ARFCN_PCS;
442 arfcn &= ~ARFCN_FLAG_MASK;
445 return GSM_BAND_1900;
446 else if (arfcn <= 124)
448 else if (arfcn >= 955 && arfcn <= 1023)
450 else if (arfcn >= 128 && arfcn <= 251)
452 else if (arfcn >= 512 && arfcn <= 885)
453 return GSM_BAND_1800;
454 else if (arfcn >= 259 && arfcn <= 293)
456 else if (arfcn >= 306 && arfcn <= 340)
458 else if (arfcn >= 350 && arfcn <= 425)
460 else if (arfcn >= 438 && arfcn <= 511)
463 return GSM_BAND_1800;
466 /* Convert an ARFCN to the frequency in MHz * 10 */
467 uint16_t gsm_arfcn2freq10(uint16_t arfcn, int uplink)
471 int is_pcs = arfcn & ARFCN_PCS;
473 arfcn &= ~ARFCN_FLAG_MASK;
478 freq10_ul = 18502 + 2 * (arfcn-512);
479 freq10_dl = freq10_ul + 800;
480 } else if (arfcn <= 124) {
481 /* Primary GSM + ARFCN 0 of E-GSM */
482 freq10_ul = 8900 + 2 * arfcn;
483 freq10_dl = freq10_ul + 450;
484 } else if (arfcn >= 955 && arfcn <= 1023) {
485 /* E-GSM and R-GSM */
486 freq10_ul = 8900 + 2 * (arfcn - 1024);
487 freq10_dl = freq10_ul + 450;
488 } else if (arfcn >= 128 && arfcn <= 251) {
490 freq10_ul = 8242 + 2 * (arfcn - 128);
491 freq10_dl = freq10_ul + 450;
492 } else if (arfcn >= 512 && arfcn <= 885) {
494 freq10_ul = 17102 + 2 * (arfcn - 512);
495 freq10_dl = freq10_ul + 950;
496 } else if (arfcn >= 259 && arfcn <= 293) {
498 freq10_ul = 4506 + 2 * (arfcn - 259);
499 freq10_dl = freq10_ul + 100;
500 } else if (arfcn >= 306 && arfcn <= 340) {
502 freq10_ul = 4790 + 2 * (arfcn - 306);
503 freq10_dl = freq10_ul + 100;
504 } else if (arfcn >= 350 && arfcn <= 425) {
506 freq10_ul = 8060 + 2 * (arfcn - 350);
507 freq10_dl = freq10_ul + 450;
508 } else if (arfcn >= 438 && arfcn <= 511) {
510 freq10_ul = 7472 + 2 * (arfcn - 438);
511 freq10_dl = freq10_ul + 300;
521 void gsm_fn2gsmtime(struct gsm_time *time, uint32_t fn)
524 time->t1 = time->fn / (26*51);
525 time->t2 = time->fn % 26;
526 time->t3 = time->fn % 51;
527 time->tc = (time->fn / 51) % 8;
530 uint32_t gsm_gsmtime2fn(struct gsm_time *time)
532 /* TS 05.02 Chapter 4.3.3 TDMA frame number */
533 return (51 * ((time->t3 - time->t2 + 26) % 26) + time->t3 + (26 * 51 * time->t1));
536 /* TS 03.03 Chapter 2.6 */
537 int gprs_tlli_type(uint32_t tlli)
539 if ((tlli & 0xc0000000) == 0xc0000000)
541 else if ((tlli & 0xc0000000) == 0x80000000)
543 else if ((tlli & 0xf8000000) == 0x78000000)
545 else if ((tlli & 0xf8000000) == 0x70000000)
546 return TLLI_AUXILIARY;
548 return TLLI_RESERVED;
551 uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type)
556 tlli = p_tmsi | 0xc0000000;
559 tlli = (p_tmsi & 0x3fffffff) | 0x80000000;