//----------------------------------------------------------------------------- // // 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 visa 2000 tag commands // by iceman // ASK/Manchester, RF/64, STT, 96 bits (complete) //----------------------------------------------------------------------------- #include "cmdlfvisa2000.h" #include #include #include #include #include #include "commonutil.h" // ARRAYLEN #include "common.h" #include "cmdparser.h" // command_t #include "comms.h" #include "ui.h" #include "graph.h" #include "cmddata.h" #include "cmdlf.h" #include "protocols.h" // for T55xx config register definitions #include "lfdemod.h" // parityTest #include "cmdlft55xx.h" // write verify #include "cmdlfem4x05.h" // #include "cliparser.h" #ifndef VISA2k_BL0CK1 #define VISA2k_BL0CK1 0x56495332 #endif static int CmdHelp(const char *Cmd); static uint8_t visa_chksum(uint32_t id) { uint8_t sum = 0; for (uint8_t i = 0; i < 32; i += 4) sum ^= (id >> i) & 0xF; return sum & 0xF; } static uint8_t visa_parity(uint32_t id) { // 4bit parity LUT uint8_t par_lut[] = { 0, 1, 1, 0 , 1, 0, 0, 1 , 1, 0, 0, 1 , 0, 1, 1, 0 }; uint8_t par = 0; par |= par_lut[(id >> 28) & 0xF ] << 7; par |= par_lut[(id >> 24) & 0xF ] << 6; par |= par_lut[(id >> 20) & 0xF ] << 5; par |= par_lut[(id >> 16) & 0xF ] << 4; par |= par_lut[(id >> 12) & 0xF ] << 3; par |= par_lut[(id >> 8) & 0xF ] << 2; par |= par_lut[(id >> 4) & 0xF ] << 1; par |= par_lut[(id & 0xF) ]; return par; } /** * * 56495332 00096ebd 00000077 —> tag id 618173 * aaaaaaaa iiiiiiii -----ppc * * a = fixed value ascii 'VIS2' * i = card id * p = even parity bit for each nibble in card id. * c = checksum (xor of card id) * **/ //see ASKDemod for what args are accepted int demodVisa2k(bool verbose) { (void) verbose; // unused so far save_restoreGB(GRAPH_SAVE); //CmdAskEdgeDetect(""); //ASK / Manchester bool st = true; if (ASKDemod_ext(64, 0, 0, 0, false, false, false, 1, &st) != PM3_SUCCESS) { PrintAndLogEx(DEBUG, "DEBUG: Error - Visa2k: ASK/Manchester Demod failed"); save_restoreGB(GRAPH_RESTORE); return PM3_ESOFT; } size_t size = DemodBufferLen; int ans = detectVisa2k(DemodBuffer, &size); if (ans < 0) { if (ans == -1) PrintAndLogEx(DEBUG, "DEBUG: Error - Visa2k: too few bits found"); else if (ans == -2) PrintAndLogEx(DEBUG, "DEBUG: Error - Visa2k: preamble not found"); else if (ans == -3) PrintAndLogEx(DEBUG, "DEBUG: Error - Visa2k: Size not correct: %zu", size); else PrintAndLogEx(DEBUG, "DEBUG: Error - Visa2k: ans: %d", ans); save_restoreGB(GRAPH_RESTORE); return PM3_ESOFT; } setDemodBuff(DemodBuffer, 96, ans); setClockGrid(g_DemodClock, g_DemodStartIdx + (ans * g_DemodClock)); //got a good demod 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); // chksum uint8_t calc = visa_chksum(raw2); uint8_t chk = raw3 & 0xF; // test checksums if (chk != calc) { PrintAndLogEx(DEBUG, "DEBUG: error: Visa2000 checksum (%s) %x - %x\n", _RED_("fail"), chk, calc); save_restoreGB(GRAPH_RESTORE); return PM3_ESOFT; } // parity uint8_t calc_par = visa_parity(raw2); uint8_t chk_par = (raw3 & 0xFF0) >> 4; if (calc_par != chk_par) { PrintAndLogEx(DEBUG, "DEBUG: error: Visa2000 parity (%s) %x - %x\n", _RED_("fail"), chk_par, calc_par); save_restoreGB(GRAPH_RESTORE); return PM3_ESOFT; } PrintAndLogEx(SUCCESS, "Visa2000 - Card " _GREEN_("%u") ", Raw: %08X%08X%08X", raw2, raw1, raw2, raw3); return PM3_SUCCESS; } static int CmdVisa2kDemod(const char *Cmd) { CLIParserContext *ctx; CLIParserInit(&ctx, "lf visa2000 demod", "Try to find visa2000 preamble, if found decode / descramble data", "lf visa2000 demod" ); void *argtable[] = { arg_param_begin, arg_param_end }; CLIExecWithReturn(ctx, Cmd, argtable, true); CLIParserFree(ctx); return demodVisa2k(true); } // 64*96*2=12288 samples just in case we just missed the first preamble we can still catch 2 of them static int CmdVisa2kReader(const char *Cmd) { CLIParserContext *ctx; CLIParserInit(&ctx, "lf visa2000 reader", "read a visa2000 tag", "lf visa2000 reader -@ -> continuous reader mode" ); void *argtable[] = { arg_param_begin, arg_lit0("@", NULL, "optional - continuous reader mode"), arg_param_end }; CLIExecWithReturn(ctx, Cmd, argtable, true); bool cm = arg_get_lit(ctx, 1); CLIParserFree(ctx); if (cm) { PrintAndLogEx(INFO, "Press " _GREEN_("") " to exit"); } do { lf_read(false, 20000); demodVisa2k(!cm); } while (cm && !kbd_enter_pressed()); return PM3_SUCCESS; } static int CmdVisa2kClone(const char *Cmd) { CLIParserContext *ctx; CLIParserInit(&ctx, "lf visa2000 clone", "clone a Visa2000 tag to a T55x7, Q5/T5555 or EM4305/4469 tag.", "lf visa2000 clone --cn 112233\n" "lf visa2000 clone --cn 112233 --q5 -> encode for Q5/T5555 tag\n" "lf visa2000 clone --cn 112233 --em -> encode for EM4305/4469" ); void *argtable[] = { arg_param_begin, arg_u64_1(NULL, "cn", "", "Visa2k card ID"), arg_lit0(NULL, "q5", "optional - specify writing to Q5/T5555 tag"), arg_lit0(NULL, "em", "optional - specify writing to EM4305/4469 tag"), arg_param_end }; CLIExecWithReturn(ctx, Cmd, argtable, false); uint32_t id = arg_get_u32_def(ctx, 1, 0); bool q5 = arg_get_lit(ctx, 2); bool em = arg_get_lit(ctx, 3); CLIParserFree(ctx); if (q5 && em) { PrintAndLogEx(FAILED, "Can't specify both Q5 and EM4305 at the same time"); return PM3_EINVARG; } uint32_t blocks[4] = {T55x7_MODULATION_MANCHESTER | T55x7_BITRATE_RF_64 | T55x7_ST_TERMINATOR | 3 << T55x7_MAXBLOCK_SHIFT, VISA2k_BL0CK1, 0}; char cardtype[16] = {"T55x7"}; // Q5 if (q5) { blocks[0] = T5555_FIXED | T5555_MODULATION_MANCHESTER | T5555_SET_BITRATE(64) | T5555_ST_TERMINATOR | 3 << T5555_MAXBLOCK_SHIFT; snprintf(cardtype, sizeof(cardtype), "Q5/T5555"); } // EM4305 if (em) { blocks[0] = EM4305_VISA2000_CONFIG_BLOCK; snprintf(cardtype, sizeof(cardtype), "EM4305/4469"); } blocks[2] = id; blocks[3] = (visa_parity(id) << 4) | visa_chksum(id); PrintAndLogEx(INFO, "Preparing to clone Visa2000 to " _YELLOW_("%s") " with CardId: " _GREEN_("%"PRIu32), cardtype, id); print_blocks(blocks, ARRAYLEN(blocks)); int res; if (em) { res = em4x05_clone_tag(blocks, ARRAYLEN(blocks), 0, false); } else { res = clone_t55xx_tag(blocks, ARRAYLEN(blocks)); } PrintAndLogEx(SUCCESS, "Done"); PrintAndLogEx(HINT, "Hint: try " _YELLOW_("`lf visa2000 reader`") " to verify"); return res; } static int CmdVisa2kSim(const char *Cmd) { CLIParserContext *ctx; CLIParserInit(&ctx, "lf visa2000 sim", "Enables simulation of visa2k card with specified card number.\n" "Simulation runs until the button is pressed or another USB command is issued.\n", "lf visa2000 sim --cn 1337" ); void *argtable[] = { arg_param_begin, arg_u64_1(NULL, "cn", "", "Visa2k card ID"), arg_param_end }; CLIExecWithReturn(ctx, Cmd, argtable, false); uint32_t id = arg_get_u32_def(ctx, 1, 0); CLIParserFree(ctx); PrintAndLogEx(SUCCESS, "Simulating Visa2000 - CardId:" _YELLOW_("%u"), id); uint32_t blocks[3] = { VISA2k_BL0CK1, id, (visa_parity(id) << 4) | visa_chksum(id) }; uint8_t bs[96]; for (int i = 0; i < 3; ++i) num_to_bytebits(blocks[i], 32, bs + i * 32); lf_asksim_t *payload = calloc(1, sizeof(lf_asksim_t) + sizeof(bs)); payload->encoding = 1; payload->invert = 0; payload->separator = 1; payload->clock = 64; memcpy(payload->data, bs, sizeof(bs)); clearCommandBuffer(); SendCommandNG(CMD_LF_ASK_SIMULATE, (uint8_t *)payload, sizeof(lf_asksim_t) + sizeof(bs)); free(payload); PacketResponseNG resp; WaitForResponse(CMD_LF_ASK_SIMULATE, &resp); PrintAndLogEx(INFO, "Done"); if (resp.status != PM3_EOPABORTED) return resp.status; return PM3_SUCCESS; } static command_t CommandTable[] = { {"help", CmdHelp, AlwaysAvailable, "This help"}, {"demod", CmdVisa2kDemod, AlwaysAvailable, "demodulate an VISA2000 tag from the GraphBuffer"}, {"reader", CmdVisa2kReader, IfPm3Lf, "attempt to read and extract tag data from the antenna"}, {"clone", CmdVisa2kClone, IfPm3Lf, "clone Visa2000 tag to T55x7 or Q5/T5555"}, {"sim", CmdVisa2kSim, IfPm3Lf, "simulate Visa2000 tag"}, {NULL, NULL, NULL, NULL} }; static int CmdHelp(const char *Cmd) { (void)Cmd; // Cmd is not used so far CmdsHelp(CommandTable); return PM3_SUCCESS; } int CmdLFVisa2k(const char *Cmd) { clearCommandBuffer(); return CmdsParse(CommandTable, Cmd); } // by iceman // find Visa2000 preamble in already demoded data int detectVisa2k(uint8_t *dest, size_t *size) { if (*size < 96) return -1; //make sure buffer has data size_t startIdx = 0; uint8_t preamble[] = {0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0}; if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) return -2; //preamble not found if (*size != 96) return -3; //wrong demoded size //return start position return (int)startIdx; }