| /* GSM utility functions, e.g. coding and decoding */ |
| /* |
| * (C) 2008 by Daniel Willmann <daniel@totalueberwachung.de> |
| * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org> |
| * (C) 2009-2010 by Harald Welte <laforge@gnumonks.org> |
| * |
| * All Rights Reserved |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| */ |
| |
| #pragma once |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| #include <osmocom/core/defs.h> |
| |
| #define ADD_MODULO(sum, delta, modulo) do { \ |
| if ((sum += delta) >= modulo) \ |
| sum -= modulo; \ |
| } while (0) |
| |
| #define GSM_MAX_FN (26*51*2048) |
| |
| struct gsm_time { |
| uint32_t fn; /* FN count */ |
| uint16_t t1; /* FN div (26*51) */ |
| uint8_t t2; /* FN modulo 26 */ |
| uint8_t t3; /* FN modulo 51 */ |
| uint8_t tc; |
| }; |
| |
| enum gsm_band { |
| GSM_BAND_850 = 1, |
| GSM_BAND_900 = 2, |
| GSM_BAND_1800 = 4, |
| GSM_BAND_1900 = 8, |
| GSM_BAND_450 = 0x10, |
| GSM_BAND_480 = 0x20, |
| GSM_BAND_750 = 0x40, |
| GSM_BAND_810 = 0x80, |
| }; |
| |
| const char *gsm_band_name(enum gsm_band band); |
| enum gsm_band gsm_band_parse(const char *mhz); |
| |
| /*! |
| * \brief Decode a sequence of GSM 03.38 encoded 7 bit characters. |
| * |
| * \param decoded The destination buffer for the decoded characters. |
| * \param n A maximum of n chars is written (incl. terminating \0). |
| * Requires n >= 1. |
| * \param user_data A pointer to the start of the packed 7bit character |
| * sequence. |
| * \param length The length of the input sequence (in octets). |
| * |
| * \returns the number of (8 bit) chars written excluding the terminating \0. |
| * This is the same like strlen(decoded). |
| */ |
| int gsm_7bit_decode_n(char *decoded, size_t n, const uint8_t *user_data, uint8_t length); |
| |
| /*! |
| * \brief Decode a sequence of 7 bit characters (USSD encoding). |
| * |
| * \see gsm_7bit_encode_n() |
| */ |
| int gsm_7bit_decode_n_ussd(char *decoded, size_t n, const uint8_t *user_data, uint8_t length); |
| |
| /*! |
| * \brief Encode a text string into GSM 03.38 encoded 7 bit characters. |
| * |
| * \param result The destination buffer for the packed 7 bit sequence. |
| * \param n A maximum of n octets is written. |
| * \param data A pointer to the start of the \0 terminated 8 bit character |
| * string. |
| * \param octets_written Iff not NULL, *octets_written will be set to the |
| * number of octets written to the result buffer. |
| * |
| * \returns the number of septets that have been created. |
| */ |
| int gsm_7bit_encode_n(uint8_t *result, size_t n, const char *data, int *octets_written); |
| |
| /*! |
| * \brief Encode a text string into GSM 03.38 encoded 7 bit characters (USSD encoding). |
| * |
| * \see gsm_7bit_decode_n() |
| */ |
| int gsm_7bit_encode_n_ussd(uint8_t *result, size_t n, const char *data, int *octets_written); |
| |
| /* the four functions below are helper functions and here for the unit test */ |
| int gsm_septets2octets(uint8_t *result, const uint8_t *rdata, uint8_t septet_len, uint8_t padding); |
| int gsm_septet_encode(uint8_t *result, const char *data); |
| uint8_t gsm_get_octet_len(const uint8_t sept_len); |
| int gsm_7bit_decode_n_hdr(char *decoded, size_t n, const uint8_t *user_data, uint8_t length, uint8_t ud_hdr_ind); |
| |
| unsigned int ms_class_gmsk_dbm(enum gsm_band band, int ms_class); |
| |
| int ms_pwr_ctl_lvl(enum gsm_band band, unsigned int dbm); |
| int ms_pwr_dbm(enum gsm_band band, uint8_t lvl); |
| |
| /* According to TS 05.08 Chapter 8.1.4 */ |
| int rxlev2dbm(uint8_t rxlev); |
| uint8_t dbm2rxlev(int dbm); |
| |
| /* According to GSM 04.08 Chapter 10.5.1.6 */ |
| static inline int ms_cm2_a5n_support(uint8_t *cm2, int n) { |
| switch (n) { |
| case 0: return 1; |
| case 1: return (cm2[0] & (1<<3)) ? 0 : 1; |
| case 2: return (cm2[2] & (1<<0)) ? 1 : 0; |
| case 3: return (cm2[2] & (1<<1)) ? 1 : 0; |
| default: |
| return 0; |
| } |
| } |
| |
| /* According to GSM 04.08 Chapter 10.5.2.29 */ |
| static inline int rach_max_trans_val2raw(int val) { return (val >> 1) & 3; } |
| static inline int rach_max_trans_raw2val(int raw) { |
| const int tbl[4] = { 1, 2, 4, 7 }; |
| return tbl[raw & 3]; |
| } |
| |
| #define ARFCN_PCS 0x8000 |
| #define ARFCN_UPLINK 0x4000 |
| #define ARFCN_FLAG_MASK 0xf000 /* Reserve the upper 5 bits for flags */ |
| |
| enum gsm_band gsm_arfcn2band(uint16_t arfcn); |
| |
| /* Convert an ARFCN to the frequency in MHz * 10 */ |
| uint16_t gsm_arfcn2freq10(uint16_t arfcn, int uplink); |
| |
| /* Convert a Frequency in MHz * 10 to ARFCN */ |
| uint16_t gsm_freq102arfcn(uint16_t freq10, int uplink); |
| |
| /* Convert from frame number to GSM time */ |
| void gsm_fn2gsmtime(struct gsm_time *time, uint32_t fn); |
| |
| /* Convert from GSM time to frame number */ |
| uint32_t gsm_gsmtime2fn(struct gsm_time *time); |
| |
| /* GSM TS 03.03 Chapter 2.6 */ |
| enum gprs_tlli_type { |
| TLLI_LOCAL, |
| TLLI_FOREIGN, |
| TLLI_RANDOM, |
| TLLI_AUXILIARY, |
| TLLI_RESERVED, |
| TLLI_G_RNTI, |
| TLLI_RAND_G_RNTI, |
| }; |
| |
| /* TS 03.03 Chapter 2.6 */ |
| int gprs_tlli_type(uint32_t tlli); |
| |
| uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type); |
| |
| /* Osmocom internal, not part of any gsm spec */ |
| enum gsm_phys_chan_config { |
| GSM_PCHAN_NONE, |
| GSM_PCHAN_CCCH, |
| GSM_PCHAN_CCCH_SDCCH4, |
| GSM_PCHAN_TCH_F, |
| GSM_PCHAN_TCH_H, |
| GSM_PCHAN_SDCCH8_SACCH8C, |
| GSM_PCHAN_PDCH, /* GPRS PDCH */ |
| GSM_PCHAN_TCH_F_PDCH, /* TCH/F if used, PDCH otherwise */ |
| GSM_PCHAN_UNKNOWN, |
| GSM_PCHAN_CCCH_SDCCH4_CBCH, |
| GSM_PCHAN_SDCCH8_SACCH8C_CBCH, |
| _GSM_PCHAN_MAX |
| }; |
| |
| /* Osmocom internal, not part of any gsm spec */ |
| enum gsm_chan_t { |
| GSM_LCHAN_NONE, |
| GSM_LCHAN_SDCCH, |
| GSM_LCHAN_TCH_F, |
| GSM_LCHAN_TCH_H, |
| GSM_LCHAN_UNKNOWN, |
| GSM_LCHAN_CCCH, |
| GSM_LCHAN_PDTCH, |
| GSM_LCHAN_CBCH, |
| _GSM_LCHAN_MAX |
| }; |
| |
| /* Deprectated functions */ |
| /* Limit encoding and decoding to use no more than this amount of buffer bytes */ |
| #define GSM_7BIT_LEGACY_MAX_BUFFER_SIZE 0x10000 |
| |
| int gsm_7bit_decode(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n() instead"); |
| int gsm_7bit_decode_ussd(char *decoded, const uint8_t *user_data, uint8_t length) OSMO_DEPRECATED("Use gsm_7bit_decode_n_ussd() instead"); |
| int gsm_7bit_encode(uint8_t *result, const char *data) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead"); |
| int gsm_7bit_encode_ussd(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n_ussd() instead"); |
| int gsm_7bit_encode_oct(uint8_t *result, const char *data, int *octets_written) OSMO_DEPRECATED("Use gsm_7bit_encode_n() instead"); |