//----------------------------------------------------------------------------- // // This code is licensed to you under the terms of the GNU GPL, version 2 or, // at your option, any later version. See the LICENSE.txt file for the text of // the license. //----------------------------------------------------------------------------- // Low frequency Farpoint G Prox II / Pyramid tag commands // Biphase, rf/ , 96 bits (unknown key calc + some bits) //----------------------------------------------------------------------------- #include "cmdlfguard.h" static int CmdHelp(const char *Cmd); static int usage_lf_guard_clone(void) { PrintAndLogEx(NORMAL, "clone a Guardall tag to a T55x7 tag."); PrintAndLogEx(NORMAL, "The facility-code is 8-bit and the card number is 16-bit. Larger values are truncated. "); PrintAndLogEx(NORMAL, "Currently work only on 26bit"); PrintAndLogEx(NORMAL, ""); PrintAndLogEx(NORMAL, "Usage: lf gprox clone [h]

"); PrintAndLogEx(NORMAL, "Options:"); PrintAndLogEx(NORMAL, " : format length 26|32|36|40"); PrintAndLogEx(NORMAL, " : 8-bit value facility code"); PrintAndLogEx(NORMAL, " : 16-bit value card number"); PrintAndLogEx(NORMAL, ""); PrintAndLogEx(NORMAL, "Examples:"); PrintAndLogEx(NORMAL, " lf gprox sim 26 123 11223"); return 0; } //by marshmellow //attempts to demodulate and identify a G_Prox_II verex/chubb card //WARNING: if it fails during some points it will destroy the DemodBuffer data // but will leave the GraphBuffer intact. //if successful it will push askraw data back to demod buffer ready for emulation static int CmdGuardDemod(const char *Cmd) { (void)Cmd; // Cmd is not used so far //Differential Biphase //get binary from ask wave if (!ASKbiphaseDemod("0 64 0 0", false)) { PrintAndLogEx(DEBUG, "DEBUG: Error - gProxII ASKbiphaseDemod failed"); return 0; } size_t size = DemodBufferLen; int preambleIndex = detectGProxII(DemodBuffer, &size); if (preambleIndex < 0) { if (preambleIndex == -1) PrintAndLogEx(DEBUG, "DEBUG: Error - gProxII too few bits found"); else if (preambleIndex == -2) PrintAndLogEx(DEBUG, "DEBUG: Error - gProxII preamble not found"); else if (preambleIndex == -3) PrintAndLogEx(DEBUG, "DEBUG: Error - gProxII size not correct: %d", size); else if (preambleIndex == -5) PrintAndLogEx(DEBUG, "DEBUG: Error - gProxII wrong spacerbits"); else PrintAndLogEx(DEBUG, "DEBUG: Error - gProxII ans: %d", preambleIndex); return 0; } //got a good demod of 96 bits uint8_t ByteStream[8] = {0x00}; uint8_t xorKey = 0; size_t startIdx = preambleIndex + 6; //start after 6 bit preamble uint8_t bits_no_spacer[90]; //so as to not mess with raw DemodBuffer copy to a new sample array memcpy(bits_no_spacer, DemodBuffer + startIdx, 90); // remove the 18 (90/5=18) parity bits (down to 72 bits (96-6-18=72)) size_t len = removeParity(bits_no_spacer, 0, 5, 3, 90); //source, startloc, paritylen, ptype, length_to_run if (len != 72) { PrintAndLogEx(DEBUG, "DEBUG: Error - gProxII spacer removal did not produce 72 bits: %u, start: %u", len, startIdx); return 0; } // get key and then get all 8 bytes of payload decoded xorKey = (uint8_t)bytebits_to_byteLSBF(bits_no_spacer, 8); for (size_t idx = 0; idx < 8; idx++) { ByteStream[idx] = ((uint8_t)bytebits_to_byteLSBF(bits_no_spacer + 8 + (idx * 8), 8)) ^ xorKey; PrintAndLogEx(DEBUG, "DEBUG: gProxII byte %u after xor: %02x", (unsigned int)idx, ByteStream[idx]); } setDemodBuff(DemodBuffer, 96, preambleIndex); setClockGrid(g_DemodClock, g_DemodStartIdx + (preambleIndex * g_DemodClock)); //ByteStream contains 8 Bytes (64 bits) of decrypted raw tag data uint8_t fmtLen = ByteStream[0] >> 2; uint32_t FC = 0; uint32_t Card = 0; //get raw 96 bits to print uint32_t raw1 = bytebits_to_byte(DemodBuffer, 32); uint32_t raw2 = bytebits_to_byte(DemodBuffer + 32, 32); uint32_t raw3 = bytebits_to_byte(DemodBuffer + 64, 32); bool unknown = false; switch (fmtLen) { case 36: FC = ((ByteStream[3] & 0x7F) << 7) | (ByteStream[4] >> 1); Card = ((ByteStream[4] & 1) << 19) | (ByteStream[5] << 11) | (ByteStream[6] << 3) | (ByteStream[7] >> 5); break; case 26: FC = ((ByteStream[3] & 0x7F) << 1) | (ByteStream[4] >> 7); Card = ((ByteStream[4] & 0x7F) << 9) | (ByteStream[5] << 1) | (ByteStream[6] >> 7); break; default : unknown = true; break; } if (!unknown) PrintAndLogEx(SUCCESS, "G-Prox-II Found: Format Len: %ubit - FC: %u - Card: %u, Raw: %08x%08x%08x", fmtLen, FC, Card, raw1, raw2, raw3); else PrintAndLogEx(SUCCESS, "Unknown G-Prox-II Fmt Found: Format Len: %u, Raw: %08x%08x%08x", fmtLen, raw1, raw2, raw3); return 1; } static int CmdGuardRead(const char *Cmd) { lf_read(true, 10000); return CmdGuardDemod(Cmd); } static int CmdGuardClone(const char *Cmd) { char cmdp = param_getchar(Cmd, 0); if (strlen(Cmd) == 0 || cmdp == 'h' || cmdp == 'H') return usage_lf_guard_clone(); uint32_t facilitycode = 0, cardnumber = 0, fc = 0, cn = 0, fmtlen = 0; uint8_t bs[96]; memset(bs, 0x00, sizeof(bs)); //GuardProxII - compat mode, ASK/Biphase, data rate 64, 3 data blocks uint32_t blocks[4] = {T55x7_MODULATION_BIPHASE | T55x7_BITRATE_RF_64 | 3 << T55x7_MAXBLOCK_SHIFT, 0, 0, 0}; if (sscanf(Cmd, "%u %u %u", &fmtlen, &fc, &cn) != 3) return usage_lf_guard_clone(); fmtlen &= 0x7f; facilitycode = (fc & 0x000000FF); cardnumber = (cn & 0x0000FFFF); if (!getGuardBits(fmtlen, facilitycode, cardnumber, bs)) { PrintAndLogEx(WARNING, "Error with tag bitstream generation."); return 1; } // Q5 if (param_getchar(Cmd, 3) == 'Q' || param_getchar(Cmd, 3) == 'q') blocks[0] = T5555_MODULATION_FSK2 | T5555_SET_BITRATE(50) | 3 << T5555_MAXBLOCK_SHIFT; blocks[1] = bytebits_to_byte(bs, 32); blocks[2] = bytebits_to_byte(bs + 32, 32); blocks[3] = bytebits_to_byte(bs + 64, 32); PrintAndLogEx(INFO, "Preparing to clone Guardall to T55x7 with Facility Code: %u, Card Number: %u", facilitycode, cardnumber); print_blocks(blocks, 4); PacketResponseNG resp; // fast push mode conn.block_after_ACK = true; for (uint8_t i = 0; i < 4; i++) { if (i == 3) { // Disable fast mode on last packet conn.block_after_ACK = false; } clearCommandBuffer(); SendCommandMIX(CMD_T55XX_WRITE_BLOCK, blocks[i], i, 0, NULL, 0); if (!WaitForResponseTimeout(CMD_ACK, &resp, T55XX_WRITE_TIMEOUT)) { PrintAndLogEx(WARNING, "Error occurred, device did not respond during write operation."); return -1; } } return 0; } static int CmdGuardSim(const char *Cmd) { // Guard uses: clk: 64, invert: 0, encoding: 2 (ASK Biphase) uint8_t clock1 = 64, encoding = 2, separator = 0, invert = 0; uint32_t facilitycode = 0, cardnumber = 0, fc = 0, cn = 0, fmtlen = 0; char cmdp = param_getchar(Cmd, 0); if (strlen(Cmd) == 0 || cmdp == 'h' || cmdp == 'H') return usage_lf_guard_sim(); if (sscanf(Cmd, "%u %u %u", &fmtlen, &fc, &cn) != 3) return usage_lf_guard_sim(); uint8_t bs[96]; memset(bs, 0x00, sizeof(bs)); fmtlen &= 0x7F; facilitycode = (fc & 0x000000FF); cardnumber = (cn & 0x0000FFFF); if (!getGuardBits(fmtlen, facilitycode, cardnumber, bs)) { PrintAndLogEx(WARNING, "Error with tag bitstream generation."); return 1; } PrintAndLogEx(SUCCESS, "Simulating Guardall - Facility Code: %u, CardNumber: %u", facilitycode, cardnumber); clearCommandBuffer(); SendCommandOLD(CMD_ASK_SIM_TAG, (clock1 << 8) | encoding, (invert << 8) | separator, sizeof(bs), bs, sizeof(bs)); PacketResponseNG resp; WaitForResponse(CMD_ASK_SIM_TAG, &resp); if (resp.status!=PM3_EOPABORTED) return resp.status; return PM3_SUCCESS; } static command_t CommandTable[] = { {"help", CmdHelp, AlwaysAvailable, "this help"}, {"demod", CmdGuardDemod, AlwaysAvailable, "demodulate a G Prox II tag from the GraphBuffer"}, {"read", CmdGuardRead, IfPm3Lf, "attempt to read and extract tag data from the antenna"}, {"clone", CmdGuardClone, IfPm3Lf, "clone Guardall tag"}, {"sim", CmdGuardSim, IfPm3Lf, "simulate Guardall tag"}, {NULL, NULL, NULL, NULL} }; static int CmdHelp(const char *Cmd) { (void)Cmd; // Cmd is not used so far CmdsHelp(CommandTable); return 0; } int CmdLFGuard(const char *Cmd) { clearCommandBuffer(); return CmdsParse(CommandTable, Cmd); } // by marshmellow // demod gProxIIDemod // error returns as -x // success returns start position in bitstream // Bitstream must contain previously askrawdemod and biphasedemoded data int detectGProxII(uint8_t *bits, size_t *size) { size_t startIdx = 0; uint8_t preamble[] = {1, 1, 1, 1, 1, 0}; // sanity check if (*size < sizeof(preamble)) return -1; if (!preambleSearch(bits, preamble, sizeof(preamble), size, &startIdx)) return -2; //preamble not found //gProxII should be 96 bits if (*size != 96) return -3; //check first 6 spacer bits to verify format if (!bits[startIdx + 5] && !bits[startIdx + 10] && !bits[startIdx + 15] && !bits[startIdx + 20] && !bits[startIdx + 25] && !bits[startIdx + 30]) { //confirmed proper separator bits found //return start position return (int) startIdx; } return -5; //spacer bits not found - not a valid gproxII } int demodGuard(void) { return CmdGuardDemod(""); } // Works for 26bits. int getGuardBits(uint8_t fmtlen, uint32_t fc, uint32_t cn, uint8_t *guardBits) { uint8_t xorKey = 0x66; uint8_t i; uint8_t pre[96]; uint8_t rawbytes[12]; memset(pre, 0x00, sizeof(pre)); memset(rawbytes, 0x00, sizeof(rawbytes)); // add format length (decimal) switch (fmtlen) { case 32: { rawbytes[1] = (32 << 2); break; } case 36: { // FC = ((ByteStream[3] & 0x7F)<<7) | (ByteStream[4]>>1); // Card = ((ByteStream[4]&1)<<19) | (ByteStream[5]<<11) | (ByteStream[6]<<3) | (ByteStream[7]>>5); rawbytes[1] = (36 << 2); // Get 26 wiegand from FacilityCode, CardNumber uint8_t wiegand[34]; memset(wiegand, 0x00, sizeof(wiegand)); num_to_bytebits(fc, 8, wiegand); num_to_bytebits(cn, 26, wiegand + 8); // add wiegand parity bits (dest, source, len) wiegand_add_parity(pre, wiegand, 34); break; } case 40: { rawbytes[1] = (40 << 2); break; } case 26: default: { rawbytes[1] = (26 << 2); // Get 26 wiegand from FacilityCode, CardNumber uint8_t wiegand[24]; memset(wiegand, 0x00, sizeof(wiegand)); num_to_bytebits(fc, 8, wiegand); num_to_bytebits(cn, 16, wiegand + 8); // add wiegand parity bits (dest, source, len) wiegand_add_parity(pre, wiegand, 24); break; } } // 2bit checksum, unknown today, // these two bits are the last ones of rawbyte[1], hence the LSHIFT above. // xor key rawbytes[0] = xorKey; rawbytes[2] = 1; rawbytes[3] = 0; // add wiegand to rawbytes for (i = 0; i < 4; ++i) rawbytes[i + 4] = bytebits_to_byte(pre + (i * 8), 8); PrintAndLogEx(DEBUG, " WIE | %s\n", sprint_hex(rawbytes, sizeof(rawbytes))); // XOR (only works on wiegand stuff) for (i = 1; i < 12; ++i) rawbytes[i] ^= xorKey ; PrintAndLogEx(DEBUG, " XOR | %s \n", sprint_hex(rawbytes, sizeof(rawbytes))); // convert rawbytes to bits in pre for (i = 0; i < 12; ++i) num_to_bytebitsLSBF(rawbytes[i], 8, pre + (i * 8)); PrintAndLogEx(DEBUG, "\n Raw | %s \n", sprint_hex(rawbytes, sizeof(rawbytes))); PrintAndLogEx(DEBUG, " Raw | %s\n", sprint_bin(pre, 64)); // add spacer bit 0 every 4 bits, starting with index 0, // 12 bytes, 24 nibbles. 24+1 extra bites. 3bytes. ie 9bytes | 1byte xorkey, 8bytes rawdata (64bits, should be enough for a 40bit wiegand) addParity(pre, guardBits + 6, 64, 5, 3); // preamble guardBits[0] = 1; guardBits[1] = 1; guardBits[2] = 1; guardBits[3] = 1; guardBits[4] = 1; guardBits[5] = 0; PrintAndLogEx(DEBUG, " FIN | %s\n", sprint_bin(guardBits, 96)); return 1; }