/* * (C) 2008 by Daniel Willmann * (C) 2009 by Holger Hans Peter Freyther * (C) 2009-2010 by Harald Welte * (C) 2010 by Nico Golde * * 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. * */ //#include #include #include #include #include #include #include #include #include #include "../../config.h" /* ETSI GSM 03.38 6.2.1 and 6.2.1.1 default alphabet * Greek symbols at hex positions 0x10 and 0x12-0x1a * left out as they can't be handled with a char and * since most phones don't display or write these * characters this would only needlessly make the code * more complex */ static unsigned char gsm_7bit_alphabet[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x0a, 0xff, 0xff, 0x0d, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x20, 0x21, 0x22, 0x23, 0x02, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 0x00, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x3c, 0x2f, 0x3e, 0x14, 0x11, 0xff, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x28, 0x40, 0x29, 0x3d, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x0c, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x5e, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x40, 0xff, 0x01, 0xff, 0x03, 0xff, 0x7b, 0x7d, 0xff, 0xff, 0xff, 0xff, 0xff, 0x5c, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x5b, 0x7e, 0x5d, 0xff, 0x7c, 0xff, 0xff, 0xff, 0xff, 0x5b, 0x0e, 0x1c, 0x09, 0xff, 0x1f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x5d, 0xff, 0xff, 0xff, 0xff, 0x5c, 0xff, 0x0b, 0xff, 0xff, 0xff, 0x5e, 0xff, 0xff, 0x1e, 0x7f, 0xff, 0xff, 0xff, 0x7b, 0x0f, 0x1d, 0xff, 0x04, 0x05, 0xff, 0xff, 0x07, 0xff, 0xff, 0xff, 0xff, 0x7d, 0x08, 0xff, 0xff, 0xff, 0x7c, 0xff, 0x0c, 0x06, 0xff, 0xff, 0x7e, 0xff, 0xff }; /* GSM 03.38 6.2.1 Character lookup for decoding */ static int gsm_septet_lookup(uint8_t ch) { int i = 0; for (; i < sizeof(gsm_7bit_alphabet); i++) { if (gsm_7bit_alphabet[i] == ch) return i; } return -1; } /* Compute the number of octets from the number of septets, for instance: 47 septets needs 41,125 = 42 octets */ uint8_t gsm_get_octet_len(const uint8_t sept_len){ int octet_len = (sept_len * 7) / 8; if ((sept_len * 7) % 8 != 0) octet_len++; return octet_len; } /* GSM 03.38 6.2.1 Character unpacking */ int gsm_7bit_decode_hdr(char *text, const uint8_t *user_data, uint8_t septet_l, uint8_t ud_hdr_ind) { int i = 0; int shift = 0; uint8_t *rtext = calloc(septet_l, sizeof(uint8_t)); uint8_t tmp; /* skip the user data header */ if (ud_hdr_ind) { /* get user data header length + 1 (for the 'user data header length'-field) */ shift = ((user_data[0] + 1) * 8) / 7; if ((((user_data[0] + 1) * 8) % 7) != 0) shift++; septet_l = septet_l - shift; } for (i = 0; i < septet_l; i++) { rtext[i] = ((user_data[((i + shift) * 7 + 7) >> 3] << (7 - (((i + shift) * 7 + 7) & 7))) | (user_data[((i + shift) * 7) >> 3] >> (((i + shift) * 7) & 7))) & 0x7f; } for (i = 0; i < septet_l; i++) { /* this is an extension character */ if(rtext[i] == 0x1b && i + 1 < septet_l){ tmp = rtext[i+1]; *(text++) = gsm_7bit_alphabet[0x7f + tmp]; i++; continue; } *(text++) = gsm_septet_lookup(rtext[i]); } if (ud_hdr_ind) i += shift; *text = '\0'; free(rtext); return i; } int gsm_7bit_decode(char *text, const uint8_t *user_data, uint8_t septet_l) { return gsm_7bit_decode_hdr(text, user_data, septet_l, 0); } /* GSM 03.38 6.2.1 Prepare character packing */ int gsm_septet_encode(uint8_t *result, const char *data) { int i, y = 0; uint8_t ch; for (i = 0; i < strlen(data); i++) { ch = data[i]; switch(ch){ /* fall-through for extension characters */ case 0x0c: case 0x5e: case 0x7b: case 0x7d: case 0x5c: case 0x5b: case 0x7e: case 0x5d: case 0x7c: result[y++] = 0x1b; default: result[y] = gsm_7bit_alphabet[ch]; break; } y++; } return y; } /* 7bit to octet packing */ int gsm_septets2octets(uint8_t *result, uint8_t *rdata, uint8_t septet_len, uint8_t padding){ int i = 0, z = 0; uint8_t cb, nb; int shift = 0; uint8_t *data = calloc(septet_len + 1, sizeof(uint8_t)); if (padding) { shift = 7 - padding; /* the first zero is needed for padding */ memcpy(data + 1, rdata, septet_len); septet_len++; } else memcpy(data, rdata, septet_len); for (i = 0; i < septet_len; i++) { if (shift == 7) { /* * special end case with the. This is necessary if the * last septet fits into the previous octet. E.g. 48 * non-extension characters: * ....ag ( a = 1100001, g = 1100111) * result[40] = 100001 XX, result[41] = 1100111 1 */ if (i + 1 < septet_len) { shift = 0; continue; } else if (i + 1 == septet_len) break; } cb = (data[i] & 0x7f) >> shift; if (i + 1 < septet_len) { nb = (data[i + 1] & 0x7f) << (7 - shift); cb = cb | nb; } result[z++] = cb; shift++; } free(data); return z; } /* GSM 03.38 6.2.1 Character packing */ int gsm_7bit_encode(uint8_t *result, const char *data) { int y = 0, z = 0; /* prepare for the worst case, every character expanding to two bytes */ uint8_t *rdata = calloc(strlen(data) * 2, sizeof(uint8_t)); y = gsm_septet_encode(rdata, data); z = gsm_septets2octets(result, rdata, y, 0); free(rdata); /* * We don't care about the number of octets (z), because they are not * unique. E.g.: * 1.) 46 non-extension characters + 1 extension character * => (46 * 7 bit + (1 * (2 * 7 bit))) / 8 bit = 42 octets * 2.) 47 non-extension characters * => (47 * 7 bit) / 8 bit = 41,125 = 42 octets * 3.) 48 non-extension characters * => (48 * 7 bit) / 8 bit = 42 octects */ return y; } /* convert power class to dBm according to GSM TS 05.05 */ unsigned int ms_class_gmsk_dbm(enum gsm_band band, int class) { switch (band) { case GSM_BAND_450: case GSM_BAND_480: case GSM_BAND_750: case GSM_BAND_900: case GSM_BAND_810: case GSM_BAND_850: if (class == 1) return 43; /* 20W */ if (class == 2) return 39; /* 8W */ if (class == 3) return 37; /* 5W */ if (class == 4) return 33; /* 2W */ if (class == 5) return 29; /* 0.8W */ break; case GSM_BAND_1800: if (class == 1) return 30; /* 1W */ if (class == 2) return 24; /* 0.25W */ if (class == 3) return 36; /* 4W */ break; case GSM_BAND_1900: if (class == 1) return 30; /* 1W */ if (class == 2) return 24; /* 0.25W */ if (class == 3) return 33; /* 2W */ break; } return -EINVAL; } /* determine power control level for given dBm value, as indicated * by the tables in chapter 4.1.1 of GSM TS 05.05 */ int ms_pwr_ctl_lvl(enum gsm_band band, unsigned int dbm) { switch (band) { case GSM_BAND_450: case GSM_BAND_480: case GSM_BAND_750: case GSM_BAND_900: case GSM_BAND_810: case GSM_BAND_850: if (dbm >= 39) return 0; else if (dbm < 5) return 19; else { /* we are guaranteed to have (5 <= dbm < 39) */ return 2 + ((39 - dbm) / 2); } break; case GSM_BAND_1800: if (dbm >= 36) return 29; else if (dbm >= 34) return 30; else if (dbm >= 32) return 31; else if (dbm == 31) return 0; else { /* we are guaranteed to have (0 <= dbm < 31) */ return (30 - dbm) / 2; } break; case GSM_BAND_1900: if (dbm >= 33) return 30; else if (dbm >= 32) return 31; else if (dbm == 31) return 0; else { /* we are guaranteed to have (0 <= dbm < 31) */ return (30 - dbm) / 2; } break; } return -EINVAL; } int ms_pwr_dbm(enum gsm_band band, uint8_t lvl) { lvl &= 0x1f; switch (band) { case GSM_BAND_450: case GSM_BAND_480: case GSM_BAND_750: case GSM_BAND_900: case GSM_BAND_810: case GSM_BAND_850: if (lvl < 2) return 39; else if (lvl < 20) return 39 - ((lvl - 2) * 2) ; else return 5; break; case GSM_BAND_1800: if (lvl < 16) return 30 - (lvl * 2); else if (lvl < 29) return 0; else return 36 - ((lvl - 29) * 2); break; case GSM_BAND_1900: if (lvl < 16) return 30 - (lvl * 2); else if (lvl < 30) return -EINVAL; else return 33 - (lvl - 30); break; } return -EINVAL; } /* According to TS 08.05 Chapter 8.1.4 */ int rxlev2dbm(uint8_t rxlev) { if (rxlev > 63) rxlev = 63; return -110 + rxlev; } /* According to TS 08.05 Chapter 8.1.4 */ uint8_t dbm2rxlev(int dbm) { int rxlev = dbm + 110; if (rxlev > 63) rxlev = 63; else if (rxlev < 0) rxlev = 0; return rxlev; } const char *gsm_band_name(enum gsm_band band) { switch (band) { case GSM_BAND_450: return "GSM450"; case GSM_BAND_480: return "GSM480"; case GSM_BAND_750: return "GSM750"; case GSM_BAND_810: return "GSM810"; case GSM_BAND_850: return "GSM850"; case GSM_BAND_900: return "GSM900"; case GSM_BAND_1800: return "DCS1800"; case GSM_BAND_1900: return "PCS1900"; } return "invalid"; } enum gsm_band gsm_band_parse(const char* mhz) { while (*mhz && !isdigit(*mhz)) mhz++; if (*mhz == '\0') return -EINVAL; switch (strtol(mhz, NULL, 10)) { case 450: return GSM_BAND_450; case 480: return GSM_BAND_480; case 750: return GSM_BAND_750; case 810: return GSM_BAND_810; case 850: return GSM_BAND_850; case 900: return GSM_BAND_900; case 1800: return GSM_BAND_1800; case 1900: return GSM_BAND_1900; default: return -EINVAL; } } enum gsm_band gsm_arfcn2band(uint16_t arfcn) { int is_pcs = arfcn & ARFCN_PCS; arfcn &= ~ARFCN_FLAG_MASK; if (is_pcs) return GSM_BAND_1900; else if (arfcn <= 124) return GSM_BAND_900; else if (arfcn >= 955 && arfcn <= 1023) return GSM_BAND_900; else if (arfcn >= 128 && arfcn <= 251) return GSM_BAND_850; else if (arfcn >= 512 && arfcn <= 885) return GSM_BAND_1800; else if (arfcn >= 259 && arfcn <= 293) return GSM_BAND_450; else if (arfcn >= 306 && arfcn <= 340) return GSM_BAND_480; else if (arfcn >= 350 && arfcn <= 425) return GSM_BAND_810; else if (arfcn >= 438 && arfcn <= 511) return GSM_BAND_750; else return GSM_BAND_1800; } /* Convert an ARFCN to the frequency in MHz * 10 */ uint16_t gsm_arfcn2freq10(uint16_t arfcn, int uplink) { uint16_t freq10_ul; uint16_t freq10_dl; int is_pcs = arfcn & ARFCN_PCS; arfcn &= ~ARFCN_FLAG_MASK; if (is_pcs) { /* DCS 1900 */ arfcn &= ~ARFCN_PCS; freq10_ul = 18502 + 2 * (arfcn-512); freq10_dl = freq10_ul + 800; } else if (arfcn <= 124) { /* Primary GSM + ARFCN 0 of E-GSM */ freq10_ul = 8900 + 2 * arfcn; freq10_dl = freq10_ul + 450; } else if (arfcn >= 955 && arfcn <= 1023) { /* E-GSM and R-GSM */ freq10_ul = 8900 + 2 * (arfcn - 1024); freq10_dl = freq10_ul + 450; } else if (arfcn >= 128 && arfcn <= 251) { /* GSM 850 */ freq10_ul = 8242 + 2 * (arfcn - 128); freq10_dl = freq10_ul + 450; } else if (arfcn >= 512 && arfcn <= 885) { /* DCS 1800 */ freq10_ul = 17102 + 2 * (arfcn - 512); freq10_dl = freq10_ul + 950; } else if (arfcn >= 259 && arfcn <= 293) { /* GSM 450 */ freq10_ul = 4506 + 2 * (arfcn - 259); freq10_dl = freq10_ul + 100; } else if (arfcn >= 306 && arfcn <= 340) { /* GSM 480 */ freq10_ul = 4790 + 2 * (arfcn - 306); freq10_dl = freq10_ul + 100; } else if (arfcn >= 350 && arfcn <= 425) { /* GSM 810 */ freq10_ul = 8060 + 2 * (arfcn - 350); freq10_dl = freq10_ul + 450; } else if (arfcn >= 438 && arfcn <= 511) { /* GSM 750 */ freq10_ul = 7472 + 2 * (arfcn - 438); freq10_dl = freq10_ul + 300; } else return 0xffff; if (uplink) return freq10_ul; else return freq10_dl; } void gsm_fn2gsmtime(struct gsm_time *time, uint32_t fn) { time->fn = fn; time->t1 = time->fn / (26*51); time->t2 = time->fn % 26; time->t3 = time->fn % 51; time->tc = (time->fn / 51) % 8; } uint32_t gsm_gsmtime2fn(struct gsm_time *time) { /* TS 05.02 Chapter 4.3.3 TDMA frame number */ return (51 * ((time->t3 - time->t2 + 26) % 26) + time->t3 + (26 * 51 * time->t1)); } /* TS 03.03 Chapter 2.6 */ int gprs_tlli_type(uint32_t tlli) { if ((tlli & 0xc0000000) == 0xc0000000) return TLLI_LOCAL; else if ((tlli & 0xc0000000) == 0x80000000) return TLLI_FOREIGN; else if ((tlli & 0xf8000000) == 0x78000000) return TLLI_RANDOM; else if ((tlli & 0xf8000000) == 0x70000000) return TLLI_AUXILIARY; return TLLI_RESERVED; } uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type) { uint32_t tlli; switch (type) { case TLLI_LOCAL: tlli = p_tmsi | 0xc0000000; break; case TLLI_FOREIGN: tlli = (p_tmsi & 0x3fffffff) | 0x80000000; break; default: tlli = 0; break; } return tlli; }