libosmogsm
0.9.3
Osmocom GSM library
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00001 /* GSM utility functions, e.g. coding and decoding */ 00002 /* 00003 * (C) 2008 by Daniel Willmann <daniel@totalueberwachung.de> 00004 * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org> 00005 * (C) 2009-2010 by Harald Welte <laforge@gnumonks.org> 00006 * 00007 * All Rights Reserved 00008 * 00009 * This program is free software; you can redistribute it and/or modify 00010 * it under the terms of the GNU General Public License as published by 00011 * the Free Software Foundation; either version 2 of the License, or 00012 * (at your option) any later version. 00013 * 00014 * This program is distributed in the hope that it will be useful, 00015 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00017 * GNU General Public License for more details. 00018 * 00019 * You should have received a copy of the GNU General Public License along 00020 * with this program; if not, write to the Free Software Foundation, Inc., 00021 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 00022 * 00023 */ 00024 00025 #pragma once 00026 00027 #include <stddef.h> 00028 #include <stdint.h> 00029 00030 #include <osmocom/core/defs.h> 00031 00032 #define ADD_MODULO(sum, delta, modulo) do { \ 00033 if ((sum += delta) >= modulo) \ 00034 sum -= modulo; \ 00035 } while (0) 00036 00037 #define GSM_MAX_FN (26*51*2048) 00038 00039 struct gsm_time { 00040 uint32_t fn; /* FN count */ 00041 uint16_t t1; /* FN div (26*51) */ 00042 uint8_t t2; /* FN modulo 26 */ 00043 uint8_t t3; /* FN modulo 51 */ 00044 uint8_t tc; 00045 }; 00046 00047 enum gsm_band { 00048 GSM_BAND_850 = 1, 00049 GSM_BAND_900 = 2, 00050 GSM_BAND_1800 = 4, 00051 GSM_BAND_1900 = 8, 00052 GSM_BAND_450 = 0x10, 00053 GSM_BAND_480 = 0x20, 00054 GSM_BAND_750 = 0x40, 00055 GSM_BAND_810 = 0x80, 00056 }; 00057 00058 const char *gsm_band_name(enum gsm_band band); 00059 enum gsm_band gsm_band_parse(const char *mhz); 00060 00074 int gsm_7bit_decode_n(char *decoded, size_t n, const uint8_t *user_data, uint8_t length); 00075 00081 int gsm_7bit_decode_n_ussd(char *decoded, size_t n, const uint8_t *user_data, uint8_t length); 00082 00095 int gsm_7bit_encode_n(uint8_t *result, size_t n, const char *data, int *octets_written); 00096 00102 int gsm_7bit_encode_n_ussd(uint8_t *result, size_t n, const char *data, int *octets_written); 00103 00104 /* the four functions below are helper functions and here for the unit test */ 00105 int gsm_septets2octets(uint8_t *result, const uint8_t *rdata, uint8_t septet_len, uint8_t padding); 00106 int gsm_septet_encode(uint8_t *result, const char *data); 00107 uint8_t gsm_get_octet_len(const uint8_t sept_len); 00108 int gsm_7bit_decode_n_hdr(char *decoded, size_t n, const uint8_t *user_data, uint8_t length, uint8_t ud_hdr_ind); 00109 00110 unsigned int ms_class_gmsk_dbm(enum gsm_band band, int ms_class); 00111 00112 int ms_pwr_ctl_lvl(enum gsm_band band, unsigned int dbm); 00113 int ms_pwr_dbm(enum gsm_band band, uint8_t lvl); 00114 00115 /* According to TS 05.08 Chapter 8.1.4 */ 00116 int rxlev2dbm(uint8_t rxlev); 00117 uint8_t dbm2rxlev(int dbm); 00118 00119 /* According to GSM 04.08 Chapter 10.5.1.6 */ 00120 static inline int ms_cm2_a5n_support(uint8_t *cm2, int n) { 00121 switch (n) { 00122 case 0: return 1; 00123 case 1: return (cm2[0] & (1<<3)) ? 0 : 1; 00124 case 2: return (cm2[2] & (1<<0)) ? 1 : 0; 00125 case 3: return (cm2[2] & (1<<1)) ? 1 : 0; 00126 default: 00127 return 0; 00128 } 00129 } 00130 00131 /* According to GSM 04.08 Chapter 10.5.2.29 */ 00132 static inline int rach_max_trans_val2raw(int val) { return (val >> 1) & 3; } 00133 static inline int rach_max_trans_raw2val(int raw) { 00134 const int tbl[4] = { 1, 2, 4, 7 }; 00135 return tbl[raw & 3]; 00136 } 00137 00138 #define ARFCN_PCS 0x8000 00139 #define ARFCN_UPLINK 0x4000 00140 #define ARFCN_FLAG_MASK 0xf000 /* Reserve the upper 5 bits for flags */ 00141 00142 enum gsm_band gsm_arfcn2band(uint16_t arfcn); 00143 00144 /* Convert an ARFCN to the frequency in MHz * 10 */ 00145 uint16_t gsm_arfcn2freq10(uint16_t arfcn, int uplink); 00146 00147 /* Convert a Frequency in MHz * 10 to ARFCN */ 00148 uint16_t gsm_freq102arfcn(uint16_t freq10, int uplink); 00149 00150 /* Convert from frame number to GSM time */ 00151 void gsm_fn2gsmtime(struct gsm_time *time, uint32_t fn); 00152 00153 /* Convert from GSM time to frame number */ 00154 uint32_t gsm_gsmtime2fn(struct gsm_time *time); 00155 00156 /* GSM TS 03.03 Chapter 2.6 */ 00157 enum gprs_tlli_type { 00158 TLLI_LOCAL, 00159 TLLI_FOREIGN, 00160 TLLI_RANDOM, 00161 TLLI_AUXILIARY, 00162 TLLI_RESERVED, 00163 TLLI_G_RNTI, 00164 TLLI_RAND_G_RNTI, 00165 }; 00166 00167 /* TS 03.03 Chapter 2.6 */ 00168 int gprs_tlli_type(uint32_t tlli); 00169 00170 uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type); 00171 00172 /* Osmocom internal, not part of any gsm spec */ 00173 enum gsm_phys_chan_config { 00174 GSM_PCHAN_NONE, 00175 GSM_PCHAN_CCCH, 00176 GSM_PCHAN_CCCH_SDCCH4, 00177 GSM_PCHAN_TCH_F, 00178 GSM_PCHAN_TCH_H, 00179 GSM_PCHAN_SDCCH8_SACCH8C, 00180 GSM_PCHAN_PDCH, /* GPRS PDCH */ 00181 GSM_PCHAN_TCH_F_PDCH, /* TCH/F if used, PDCH otherwise */ 00182 GSM_PCHAN_UNKNOWN, 00183 GSM_PCHAN_CCCH_SDCCH4_CBCH, 00184 GSM_PCHAN_SDCCH8_SACCH8C_CBCH, 00185 _GSM_PCHAN_MAX 00186 }; 00187 00188 /* Osmocom internal, not part of any gsm spec */ 00189 enum gsm_chan_t { 00190 GSM_LCHAN_NONE, 00191 GSM_LCHAN_SDCCH, 00192 GSM_LCHAN_TCH_F, 00193 GSM_LCHAN_TCH_H, 00194 GSM_LCHAN_UNKNOWN, 00195 GSM_LCHAN_CCCH, 00196 GSM_LCHAN_PDTCH, 00197 GSM_LCHAN_CBCH, 00198 _GSM_LCHAN_MAX 00199 }; 00200 00201 /* Deprectated functions */ 00202 /* Limit encoding and decoding to use no more than this amount of buffer bytes */ 00203 #define GSM_7BIT_LEGACY_MAX_BUFFER_SIZE 0x10000 00204 00205 int gsm_7bit_decode(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n() instead"); 00206 int gsm_7bit_decode_ussd(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n_ussd() instead"); 00207 int gsm_7bit_encode(uint8_t *result, const char *data) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead"); 00208 int gsm_7bit_encode_ussd(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n_ussd() instead"); 00209 int gsm_7bit_encode_oct(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead");