Piotr Krysik | 4e4a92e | 2018-05-11 11:39:23 +0200 | [diff] [blame] | 1 | /*! \file gsm_utils.h |
| 2 | * GSM utility functions, e.g. coding and decoding. */ |
| 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 { |
| 53 | GSM_BAND_850 = 1, |
| 54 | GSM_BAND_900 = 2, |
| 55 | GSM_BAND_1800 = 4, |
| 56 | GSM_BAND_1900 = 8, |
| 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 | |
| 68 | /*! |
| 69 | * Decode a sequence of GSM 03.38 encoded 7 bit characters. |
| 70 | * |
| 71 | * \param decoded The destination buffer for the decoded characters. |
| 72 | * \param n A maximum of n chars is written (incl. terminating \0). |
| 73 | * Requires n >= 1. |
| 74 | * \param user_data A pointer to the start of the packed 7bit character |
| 75 | * sequence. |
| 76 | * \param length The length of the input sequence in septets, for |
| 77 | * example pass octet_length*8/7. |
| 78 | * |
| 79 | * \returns the number of (8 bit) chars written excluding the terminating \0. |
| 80 | * This is the same like strlen(decoded). |
| 81 | */ |
| 82 | //int gsm_7bit_decode_n(char *decoded, size_t n, const uint8_t *user_data, uint8_t length); |
| 83 | |
| 84 | ///*! |
| 85 | // * Decode a sequence of 7 bit characters (USSD encoding). |
| 86 | // * |
| 87 | // * \see gsm_7bit_encode_n() |
| 88 | // */ |
| 89 | //int gsm_7bit_decode_n_ussd(char *decoded, size_t n, const uint8_t *user_data, uint8_t length); |
| 90 | |
| 91 | ///*! |
| 92 | // * Encode a text string into GSM 03.38 encoded 7 bit characters. |
| 93 | // * |
| 94 | // * \param result The destination buffer for the packed 7 bit sequence. |
| 95 | // * \param n A maximum of n octets is written. |
| 96 | // * \param data A pointer to the start of the \0 terminated 8 bit character |
| 97 | // * string. |
| 98 | // * \param octets_written Iff not NULL, *octets_written will be set to the |
| 99 | // * number of octets written to the result buffer. |
| 100 | // * |
| 101 | // * \returns the number of septets that have been created. |
| 102 | // */ |
| 103 | //int gsm_7bit_encode_n(uint8_t *result, size_t n, const char *data, int *octets_written); |
| 104 | |
| 105 | ///*! |
| 106 | // * Encode a text string into GSM 03.38 encoded 7 bit characters (USSD encoding). |
| 107 | // * |
| 108 | // * \see gsm_7bit_decode_n() |
| 109 | // */ |
| 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 */ |
| 183 | //enum gprs_tlli_type { |
| 184 | // TLLI_LOCAL, |
| 185 | // TLLI_FOREIGN, |
| 186 | // TLLI_RANDOM, |
| 187 | // TLLI_AUXILIARY, |
| 188 | // TLLI_RESERVED, |
| 189 | // TLLI_G_RNTI, |
| 190 | // TLLI_RAND_G_RNTI, |
| 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 */ |
| 199 | //enum gsm_phys_chan_config { |
| 200 | // GSM_PCHAN_NONE, |
| 201 | // GSM_PCHAN_CCCH, |
| 202 | // GSM_PCHAN_CCCH_SDCCH4, |
| 203 | // GSM_PCHAN_TCH_F, |
| 204 | // GSM_PCHAN_TCH_H, |
| 205 | // GSM_PCHAN_SDCCH8_SACCH8C, |
| 206 | // GSM_PCHAN_PDCH, /* GPRS PDCH */ |
| 207 | // GSM_PCHAN_TCH_F_PDCH, /* TCH/F if used, PDCH otherwise */ |
| 208 | // GSM_PCHAN_UNKNOWN, |
| 209 | // GSM_PCHAN_CCCH_SDCCH4_CBCH, |
| 210 | // GSM_PCHAN_SDCCH8_SACCH8C_CBCH, |
| 211 | // GSM_PCHAN_TCH_F_TCH_H_PDCH, |
| 212 | // _GSM_PCHAN_MAX |
| 213 | //}; |
| 214 | |
| 215 | ///* Osmocom internal, not part of any gsm spec */ |
| 216 | //enum gsm_chan_t { |
| 217 | // GSM_LCHAN_NONE, |
| 218 | // GSM_LCHAN_SDCCH, |
| 219 | // GSM_LCHAN_TCH_F, |
| 220 | // GSM_LCHAN_TCH_H, |
| 221 | // GSM_LCHAN_UNKNOWN, |
| 222 | // GSM_LCHAN_CCCH, |
| 223 | // GSM_LCHAN_PDTCH, |
| 224 | // GSM_LCHAN_CBCH, |
| 225 | // _GSM_LCHAN_MAX |
| 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"); |