X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/05ddb52c43f932db852e18fe6836bee71e91f74e..61500621bcceb9b210ee2191f257244bf80de474:/armsrc/iso14443a.c?ds=sidebyside diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c index 0bd681d9..83907fce 100644 --- a/armsrc/iso14443a.c +++ b/armsrc/iso14443a.c @@ -15,12 +15,13 @@ #include "util.h" #include "string.h" #include "cmd.h" - #include "iso14443crc.h" #include "iso14443a.h" #include "crapto1.h" #include "mifareutil.h" #include "BigBuf.h" +#include "protocols.h" + static uint32_t iso14a_timeout; int rsamples = 0; uint8_t trigger = 0; @@ -213,6 +214,12 @@ void AppendCrc14443a(uint8_t* data, int len) ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1); } +void AppendCrc14443b(uint8_t* data, int len) +{ + ComputeCrc14443(CRC_14443_B,data,len,data+len,data+len+1); +} + + //============================================================================= // ISO 14443 Type A - Miller decoder //============================================================================= @@ -238,8 +245,6 @@ static tUart Uart; // 0111 - a 2 tick wide pause shifted left // 1001 - a 2 tick wide pause shifted right const bool Mod_Miller_LUT[] = { -// TRUE, TRUE, FALSE, TRUE, FALSE, FALSE, FALSE, FALSE, -// TRUE, TRUE, FALSE, FALSE, TRUE, FALSE, FALSE, FALSE FALSE, TRUE, FALSE, TRUE, FALSE, FALSE, FALSE, TRUE, FALSE, TRUE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE }; @@ -279,8 +284,8 @@ static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) // Sequence X followed by Sequence Y followed by Sequence Z (111100x1 11111111 00x11111) // we therefore look for a ...xx11111111111100x11111xxxxxx... pattern // (12 '1's followed by 2 '0's, eventually followed by another '0', followed by 5 '1's) -#define ISO14443A_STARTBIT_MASK 0x07FFEF80 // mask is 00000111 11111111 11101111 10000000 -#define ISO14443A_STARTBIT_PATTERN 0x07FF8F80 // pattern is 00000111 11111111 10001111 10000000 + #define ISO14443A_STARTBIT_MASK 0x07FFEF80 // mask is 00000111 11111111 11101111 10000000 + #define ISO14443A_STARTBIT_PATTERN 0x07FF8F80 // pattern is 00000111 11111111 10001111 10000000 if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 0)) == ISO14443A_STARTBIT_PATTERN >> 0) Uart.syncBit = 7; else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 1)) == ISO14443A_STARTBIT_PATTERN >> 1) Uart.syncBit = 6; else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 2)) == ISO14443A_STARTBIT_PATTERN >> 2) Uart.syncBit = 5; @@ -551,12 +556,8 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { LEDsoff(); - // We won't start recording the frames that we acquire until we trigger; - // a good trigger condition to get started is probably when we see a - // response from the tag. - // triggered == FALSE -- to wait first for card - bool triggered = !(param & 0x03); - + iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER); + // Allocate memory from BigBuf for some buffers // free all previous allocations first BigBuf_free(); @@ -583,8 +584,6 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { bool TagIsActive = FALSE; bool ReaderIsActive = FALSE; - iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER); - // Set up the demodulator for tag -> reader responses. DemodInit(receivedResponse, receivedResponsePar); @@ -594,6 +593,12 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { // Setup and start DMA. FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); + // We won't start recording the frames that we acquire until we trigger; + // a good trigger condition to get started is probably when we see a + // response from the tag. + // triggered == FALSE -- to wait first for card + bool triggered = !(param & 0x03); + // And now we loop, receiving samples. for(uint32_t rsamples = 0; TRUE; ) { @@ -655,7 +660,7 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { TRUE)) break; } /* And ready to receive another command. */ - UartInit(receivedCmd, receivedCmdPar); + UartReset(); /* And also reset the demod code, which might have been */ /* false-triggered by the commands from the reader. */ DemodReset(); @@ -680,6 +685,9 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { // And ready to receive another response. DemodReset(); + // And reset the Miller decoder including itS (now outdated) input buffer + UartInit(receivedCmd, receivedCmdPar); + LED_C_OFF(); } TagIsActive = (Demod.state != DEMOD_UNSYNCD); @@ -1026,6 +1034,9 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data) .modulation_n = 0 }; + // We need to listen to the high-frequency, peak-detected path. + iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN); + BigBuf_free_keep_EM(); // allocate buffers: @@ -1054,16 +1065,12 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data) int happened2 = 0; int cmdsRecvd = 0; - // We need to listen to the high-frequency, peak-detected path. - iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN); - cmdsRecvd = 0; tag_response_info_t* p_response; LED_A_ON(); for(;;) { // Clean receive command buffer - if(!GetIso14443aCommandFromReader(receivedCmd, receivedCmdPar, &len)) { DbpString("Button press"); break; @@ -1337,7 +1344,7 @@ void CodeIso14443aBitsAsReaderPar(const uint8_t *cmd, uint16_t bits, const uint8 } // Only transmit parity bit if we transmitted a complete byte - if (j == 8) { + if (j == 8 && parity != NULL) { // Get the parity bit if (parity[i>>3] & (0x80 >> (i&0x0007))) { // Sequence X @@ -1631,6 +1638,7 @@ static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, uint8_t *receive } } + void ReaderTransmitBitsPar(uint8_t* frame, uint16_t bits, uint8_t *par, uint32_t *timing) { CodeIso14443aBitsAsReaderPar(frame, bits, par); @@ -1646,11 +1654,13 @@ void ReaderTransmitBitsPar(uint8_t* frame, uint16_t bits, uint8_t *par, uint32_t } } + void ReaderTransmitPar(uint8_t* frame, uint16_t len, uint8_t *par, uint32_t *timing) { ReaderTransmitBitsPar(frame, len*8, par, timing); } + void ReaderTransmitBits(uint8_t* frame, uint16_t len, uint32_t *timing) { // Generate parity and redirect @@ -1659,6 +1669,7 @@ void ReaderTransmitBits(uint8_t* frame, uint16_t len, uint32_t *timing) ReaderTransmitBitsPar(frame, len, par, timing); } + void ReaderTransmit(uint8_t* frame, uint16_t len, uint32_t *timing) { // Generate parity and redirect @@ -1932,15 +1943,38 @@ void ReaderIso14443a(UsbCommand *c) if(param & ISO14A_RAW) { if(param & ISO14A_APPEND_CRC) { - AppendCrc14443a(cmd,len); + if(param & ISO14A_TOPAZMODE) { + AppendCrc14443b(cmd,len); + } else { + AppendCrc14443a(cmd,len); + } len += 2; if (lenbits) lenbits += 16; } - if(lenbits>0) { - GetParity(cmd, lenbits/8, par); - ReaderTransmitBitsPar(cmd, lenbits, par, NULL); - } else { - ReaderTransmit(cmd,len, NULL); + if(lenbits>0) { // want to send a specific number of bits (e.g. short commands) + if(param & ISO14A_TOPAZMODE) { + int bits_to_send = lenbits; + uint16_t i = 0; + ReaderTransmitBitsPar(&cmd[i++], MIN(bits_to_send, 7), NULL, NULL); // first byte is always short (7bits) and no parity + bits_to_send -= 7; + while (bits_to_send > 0) { + ReaderTransmitBitsPar(&cmd[i++], MIN(bits_to_send, 8), NULL, NULL); // following bytes are 8 bit and no parity + bits_to_send -= 8; + } + } else { + GetParity(cmd, lenbits/8, par); + ReaderTransmitBitsPar(cmd, lenbits, par, NULL); // bytes are 8 bit with odd parity + } + } else { // want to send complete bytes only + if(param & ISO14A_TOPAZMODE) { + uint16_t i = 0; + ReaderTransmitBitsPar(&cmd[i++], 7, NULL, NULL); // first byte: 7 bits, no paritiy + while (i < len) { + ReaderTransmitBitsPar(&cmd[i++], 8, NULL, NULL); // following bytes: 8 bits, no paritiy + } + } else { + ReaderTransmit(cmd,len, NULL); // 8 bits, odd parity + } } arg0 = ReaderReceive(buf, par); cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf)); @@ -1976,7 +2010,7 @@ int32_t dist_nt(uint32_t nt1, uint32_t nt2) { nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i; nttmp2 = prng_successor(nttmp2, 1); - if (nttmp2 == nt1) return -i; + if (nttmp2 == nt1) return -i; } return(-99999); // either nt1 or nt2 are invalid nonces @@ -1999,6 +2033,10 @@ void ReaderMifare(bool first_try) uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE]; uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE]; + if (first_try) { + iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD); + } + // free eventually allocated BigBuf memory. We want all for tracing. BigBuf_free(); @@ -2018,20 +2056,20 @@ void ReaderMifare(bool first_try) byte_t par_list[8] = {0x00}; byte_t ks_list[8] = {0x00}; + #define PRNG_SEQUENCE_LENGTH (1 << 16); static uint32_t sync_time; - static uint32_t sync_cycles; + static int32_t sync_cycles; int catch_up_cycles = 0; int last_catch_up = 0; + uint16_t elapsed_prng_sequences; uint16_t consecutive_resyncs = 0; int isOK = 0; if (first_try) { mf_nr_ar3 = 0; - iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD); sync_time = GetCountSspClk() & 0xfffffff8; - sync_cycles = 65536; // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces). + sync_cycles = PRNG_SEQUENCE_LENGTH; // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the tag nonces). nt_attacked = 0; - nt = 0; par[0] = 0; } else { @@ -2045,33 +2083,84 @@ void ReaderMifare(bool first_try) LED_B_OFF(); LED_C_OFF(); - + + #define MAX_UNEXPECTED_RANDOM 4 // maximum number of unexpected (i.e. real) random numbers when trying to sync. Then give up. + #define MAX_SYNC_TRIES 32 + #define NUM_DEBUG_INFOS 8 // per strategy + #define MAX_STRATEGY 3 + uint16_t unexpected_random = 0; + uint16_t sync_tries = 0; + int16_t debug_info_nr = -1; + uint16_t strategy = 0; + int32_t debug_info[MAX_STRATEGY][NUM_DEBUG_INFOS]; + uint32_t select_time; + uint32_t halt_time; + for(uint16_t i = 0; TRUE; i++) { + LED_C_ON(); WDT_HIT(); // Test if the action was cancelled if(BUTTON_PRESS()) { + isOK = -1; break; } - LED_C_ON(); + if (strategy == 2) { + // test with additional hlt command + halt_time = 0; + int len = mifare_sendcmd_short(NULL, false, 0x50, 0x00, receivedAnswer, receivedAnswerPar, &halt_time); + if (len && MF_DBGLEVEL >= 3) { + Dbprintf("Unexpected response of %d bytes to hlt command (additional debugging).", len); + } + } + if (strategy == 3) { + // test with FPGA power off/on + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + SpinDelay(200); + iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD); + SpinDelay(100); + } + if(!iso14443a_select_card(uid, NULL, &cuid)) { if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Can't select card"); continue; } + select_time = GetCountSspClk(); - sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles; - catch_up_cycles = 0; + elapsed_prng_sequences = 1; + if (debug_info_nr == -1) { + sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles; + catch_up_cycles = 0; - // if we missed the sync time already, advance to the next nonce repeat - while(GetCountSspClk() > sync_time) { - sync_time = (sync_time & 0xfffffff8) + sync_cycles; - } + // if we missed the sync time already, advance to the next nonce repeat + while(GetCountSspClk() > sync_time) { + elapsed_prng_sequences++; + sync_time = (sync_time & 0xfffffff8) + sync_cycles; + } - // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) - ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time); + // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) + ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time); + } else { + // collect some information on tag nonces for debugging: + #define DEBUG_FIXED_SYNC_CYCLES PRNG_SEQUENCE_LENGTH + if (strategy == 0) { + // nonce distances at fixed time after card select: + sync_time = select_time + DEBUG_FIXED_SYNC_CYCLES; + } else if (strategy == 1) { + // nonce distances at fixed time between authentications: + sync_time = sync_time + DEBUG_FIXED_SYNC_CYCLES; + } else if (strategy == 2) { + // nonce distances at fixed time after halt: + sync_time = halt_time + DEBUG_FIXED_SYNC_CYCLES; + } else { + // nonce_distances at fixed time after power on + sync_time = DEBUG_FIXED_SYNC_CYCLES; + } + ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time); + } // Receive the (4 Byte) "random" nonce if (!ReaderReceive(receivedAnswer, receivedAnswerPar)) { @@ -2089,13 +2178,37 @@ void ReaderMifare(bool first_try) int nt_distance = dist_nt(previous_nt, nt); if (nt_distance == 0) { nt_attacked = nt; - } - else { - if (nt_distance == -99999) { // invalid nonce received, try again - continue; + } else { + if (nt_distance == -99999) { // invalid nonce received + unexpected_random++; + if (unexpected_random > MAX_UNEXPECTED_RANDOM) { + isOK = -3; // Card has an unpredictable PRNG. Give up + break; + } else { + continue; // continue trying... + } + } + if (++sync_tries > MAX_SYNC_TRIES) { + if (strategy > MAX_STRATEGY || MF_DBGLEVEL < 3) { + isOK = -4; // Card's PRNG runs at an unexpected frequency or resets unexpectedly + break; + } else { // continue for a while, just to collect some debug info + debug_info[strategy][debug_info_nr] = nt_distance; + debug_info_nr++; + if (debug_info_nr == NUM_DEBUG_INFOS) { + strategy++; + debug_info_nr = 0; + } + continue; + } + } + sync_cycles = (sync_cycles - nt_distance/elapsed_prng_sequences); + if (sync_cycles <= 0) { + sync_cycles += PRNG_SEQUENCE_LENGTH; + } + if (MF_DBGLEVEL >= 3) { + Dbprintf("calibrating in cycle %d. nt_distance=%d, elapsed_prng_sequences=%d, new sync_cycles: %d\n", i, nt_distance, elapsed_prng_sequences, sync_cycles); } - sync_cycles = (sync_cycles - nt_distance); - if (MF_DBGLEVEL >= 3) Dbprintf("calibrating in cycle %d. nt_distance=%d, Sync_cycles: %d\n", i, nt_distance, sync_cycles); continue; } } @@ -2106,6 +2219,7 @@ void ReaderMifare(bool first_try) catch_up_cycles = 0; continue; } + catch_up_cycles /= elapsed_prng_sequences; if (catch_up_cycles == last_catch_up) { consecutive_resyncs++; } @@ -2119,6 +2233,9 @@ void ReaderMifare(bool first_try) else { sync_cycles = sync_cycles + catch_up_cycles; if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d for the fourth time consecutively (nt_distance = %d). Adjusting sync_cycles to %d.\n", i, -catch_up_cycles, sync_cycles); + last_catch_up = 0; + catch_up_cycles = 0; + consecutive_resyncs = 0; } continue; } @@ -2126,12 +2243,10 @@ void ReaderMifare(bool first_try) consecutive_resyncs = 0; // Receive answer. This will be a 4 Bit NACK when the 8 parity bits are OK after decoding - if (ReaderReceive(receivedAnswer, receivedAnswerPar)) - { + if (ReaderReceive(receivedAnswer, receivedAnswerPar)) { catch_up_cycles = 8; // the PRNG is delayed by 8 cycles due to the NAC (4Bits = 0x05 encrypted) transfer - if (nt_diff == 0) - { + if (nt_diff == 0) { par_low = par[0] & 0xE0; // there is no need to check all parities for other nt_diff. Parity Bits for mf_nr_ar[0..2] won't change } @@ -2154,6 +2269,10 @@ void ReaderMifare(bool first_try) if (nt_diff == 0 && first_try) { par[0]++; + if (par[0] == 0x00) { // tried all 256 possible parities without success. Card doesn't send NACK. + isOK = -2; + break; + } } else { par[0] = ((par[0] & 0x1F) + 1) | par_low; } @@ -2162,6 +2281,16 @@ void ReaderMifare(bool first_try) mf_nr_ar[3] &= 0x1F; + + if (isOK == -4) { + if (MF_DBGLEVEL >= 3) { + for (uint16_t i = 0; i <= MAX_STRATEGY; i++) { + for(uint16_t j = 0; j < NUM_DEBUG_INFOS; j++) { + Dbprintf("collected debug info[%d][%d] = %d", i, j, debug_info[i][j]); + } + } + } + } byte_t buf[28]; memcpy(buf + 0, uid, 4); @@ -2170,7 +2299,7 @@ void ReaderMifare(bool first_try) memcpy(buf + 16, ks_list, 8); memcpy(buf + 24, mf_nr_ar, 4); - cmd_send(CMD_ACK,isOK,0,0,buf,28); + cmd_send(CMD_ACK, isOK, 0, 0, buf, 28); // Thats it... FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); @@ -2179,20 +2308,35 @@ void ReaderMifare(bool first_try) set_tracing(FALSE); } +typedef struct { + uint32_t cuid; + uint8_t sector; + uint8_t keytype; + uint32_t nonce; + uint32_t ar; + uint32_t nr; + uint32_t nonce2; + uint32_t ar2; + uint32_t nr2; +} nonces_t; + /** *MIFARE 1K simulate. * *@param flags : * FLAG_INTERACTIVE - In interactive mode, we are expected to finish the operation with an ACK - * 4B_FLAG_UID_IN_DATA - means that there is a 4-byte UID in the data-section, we're expected to use that - * 7B_FLAG_UID_IN_DATA - means that there is a 7-byte UID in the data-section, we're expected to use that + * FLAG_4B_UID_IN_DATA - means that there is a 4-byte UID in the data-section, we're expected to use that + * FLAG_7B_UID_IN_DATA - means that there is a 7-byte UID in the data-section, we're expected to use that + * FLAG_10B_UID_IN_DATA - use 10-byte UID in the data-section not finished * FLAG_NR_AR_ATTACK - means we should collect NR_AR responses for bruteforcing later - *@param exitAfterNReads, exit simulation after n blocks have been read, 0 is inifite + * FLAG_RANDOM_NONCE - means we should generate some pseudo-random nonce data (only allows moebius attack) + *@param exitAfterNReads, exit simulation after n blocks have been read, 0 is infinite ... + * (unless reader attack mode enabled then it runs util it gets enough nonces to recover all keys attmpted) */ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *datain) { int cardSTATE = MFEMUL_NOFIELD; - int _7BUID = 0; + int _UID_LEN = 0; // 4, 7, 10 int vHf = 0; // in mV int res; uint32_t selTimer = 0; @@ -2216,30 +2360,40 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * uint8_t response[MAX_MIFARE_FRAME_SIZE]; uint8_t response_par[MAX_MIFARE_PARITY_SIZE]; - uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID + uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; // !!! - uint8_t rSAK[] = {0x08, 0xb6, 0xdd}; - uint8_t rSAK1[] = {0x04, 0xda, 0x17}; + uint8_t rUIDBCC3[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; + + uint8_t rSAKfinal[]= {0x08, 0xb6, 0xdd}; // mifare 1k indicated + uint8_t rSAK1[] = {0x04, 0xda, 0x17}; // indicate UID not finished uint8_t rAUTH_NT[] = {0x01, 0x02, 0x03, 0x04}; uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00}; - //Here, we collect UID,NT,AR,NR,UID2,NT2,AR2,NR2 - // This can be used in a reader-only attack. - // (it can also be retrieved via 'hf 14a list', but hey... - uint32_t ar_nr_responses[] = {0,0,0,0,0,0,0,0}; - uint8_t ar_nr_collected = 0; - - // free eventually allocated BigBuf memory but keep Emulator Memory - BigBuf_free_keep_EM(); - - // clear trace - clear_trace(); - set_tracing(TRUE); + //Here, we collect UID,sector,keytype,NT,AR,NR,NT2,AR2,NR2 + // This will be used in the reader-only attack. + + //allow collecting up to 8 sets of nonces to allow recovery of up to 8 keys + #define ATTACK_KEY_COUNT 8 // keep same as define in cmdhfmf.c -> readerAttack() + nonces_t ar_nr_resp[ATTACK_KEY_COUNT*2]; //*2 for 2 separate attack types (nml, moebius) + memset(ar_nr_resp, 0x00, sizeof(ar_nr_resp)); + + uint8_t ar_nr_collected[ATTACK_KEY_COUNT*2]; //*2 for 2nd attack type (moebius) + memset(ar_nr_collected, 0x00, sizeof(ar_nr_collected)); + uint8_t nonce1_count = 0; + uint8_t nonce2_count = 0; + uint8_t moebius_n_count = 0; + bool gettingMoebius = false; + uint8_t mM = 0; //moebius_modifier for collection storage // Authenticate response - nonce - uint32_t nonce = bytes_to_num(rAUTH_NT, 4); + uint32_t nonce; + if (flags & FLAG_RANDOM_NONCE) { + nonce = prand(); + } else { + nonce = bytes_to_num(rAUTH_NT, 4); + } //-- Determine the UID // Can be set from emulator memory, incoming data @@ -2249,52 +2403,111 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * // 4B uid comes from data-portion of packet memcpy(rUIDBCC1,datain,4); rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; - + _UID_LEN = 4; } else if (flags & FLAG_7B_UID_IN_DATA) { // 7B uid comes from data-portion of packet memcpy(&rUIDBCC1[1],datain,3); memcpy(rUIDBCC2, datain+3, 4); - _7BUID = true; + _UID_LEN = 7; + } else if (flags & FLAG_10B_UID_IN_DATA) { + memcpy(&rUIDBCC1[1], datain, 3); + memcpy(&rUIDBCC2[1], datain+3, 3); + memcpy( rUIDBCC3, datain+6, 4); + _UID_LEN = 10; } else { - // get UID from emul memory + // get UID from emul memory - guess at length emlGetMemBt(receivedCmd, 7, 1); - _7BUID = !(receivedCmd[0] == 0x00); - if (!_7BUID) { // ---------- 4BUID + if (receivedCmd[0] == 0x00) { // ---------- 4BUID emlGetMemBt(rUIDBCC1, 0, 4); + _UID_LEN = 4; } else { // ---------- 7BUID emlGetMemBt(&rUIDBCC1[1], 0, 3); emlGetMemBt(rUIDBCC2, 3, 4); + _UID_LEN = 7; } } - /* - * Regardless of what method was used to set the UID, set fifth byte and modify - * the ATQA for 4 or 7-byte UID - */ - rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; - if (_7BUID) { - rATQA[0] = 0x44; - rUIDBCC1[0] = 0x88; - rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3]; + switch (_UID_LEN) { + case 4: + // save CUID + cuid = bytes_to_num(rUIDBCC1, 4); + // BCC + rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; + if (MF_DBGLEVEL >= 2) { + Dbprintf("4B UID: %02x%02x%02x%02x", + rUIDBCC1[0], + rUIDBCC1[1], + rUIDBCC1[2], + rUIDBCC1[3] + ); + } + break; + case 7: + rATQA[0] |= 0x40; + // save CUID + cuid = bytes_to_num(rUIDBCC2, 4); + // CascadeTag, CT + rUIDBCC1[0] = 0x88; + // BCC + rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; + rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3]; + if (MF_DBGLEVEL >= 2) { + Dbprintf("7B UID: %02x %02x %02x %02x %02x %02x %02x", + rUIDBCC1[1], + rUIDBCC1[2], + rUIDBCC1[3], + rUIDBCC2[0], + rUIDBCC2[1], + rUIDBCC2[2], + rUIDBCC2[3] + ); + } + break; + case 10: + rATQA[0] |= 0x80; + //sak_10[0] &= 0xFB; + // save CUID + cuid = bytes_to_num(rUIDBCC3, 4); + // CascadeTag, CT + rUIDBCC1[0] = 0x88; + rUIDBCC2[0] = 0x88; + // BCC + rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; + rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3]; + rUIDBCC3[4] = rUIDBCC3[0] ^ rUIDBCC3[1] ^ rUIDBCC3[2] ^ rUIDBCC3[3]; + + if (MF_DBGLEVEL >= 2) { + Dbprintf("10B UID: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x", + rUIDBCC1[1], + rUIDBCC1[2], + rUIDBCC1[3], + rUIDBCC2[1], + rUIDBCC2[2], + rUIDBCC2[3], + rUIDBCC3[0], + rUIDBCC3[1], + rUIDBCC3[2], + rUIDBCC3[3] + ); + } + break; + default: + break; } // We need to listen to the high-frequency, peak-detected path. iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN); + // free eventually allocated BigBuf memory but keep Emulator Memory + BigBuf_free_keep_EM(); - if (MF_DBGLEVEL >= 1) { - if (!_7BUID) { - Dbprintf("4B UID: %02x%02x%02x%02x", - rUIDBCC1[0], rUIDBCC1[1], rUIDBCC1[2], rUIDBCC1[3]); - } else { - Dbprintf("7B UID: (%02x)%02x%02x%02x%02x%02x%02x%02x", - rUIDBCC1[0], rUIDBCC1[1], rUIDBCC1[2], rUIDBCC1[3], - rUIDBCC2[0], rUIDBCC2[1] ,rUIDBCC2[2], rUIDBCC2[3]); - } - } + // clear trace + clear_trace(); + set_tracing(TRUE); bool finished = FALSE; - while (!BUTTON_PRESS() && !finished) { + bool button_pushed = BUTTON_PRESS(); + while (!button_pushed && !finished && !usb_poll_validate_length()) { WDT_HIT(); // find reader field @@ -2304,11 +2517,10 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * cardSTATE_TO_IDLE(); LED_A_ON(); } - } - if(cardSTATE == MFEMUL_NOFIELD) continue; + } + if (cardSTATE == MFEMUL_NOFIELD) continue; //Now, get data - res = EmGetCmd(receivedCmd, &len, receivedCmd_par); if (res == 2) { //Field is off! cardSTATE = MFEMUL_NOFIELD; @@ -2317,11 +2529,11 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * } else if (res == 1) { break; //return value 1 means button press } - + // REQ or WUP request in ANY state and WUP in HALTED state - if (len == 1 && ((receivedCmd[0] == 0x26 && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == 0x52)) { + if (len == 1 && ((receivedCmd[0] == ISO14443A_CMD_REQA && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == ISO14443A_CMD_WUPA)) { selTimer = GetTickCount(); - EmSendCmdEx(rATQA, sizeof(rATQA), (receivedCmd[0] == 0x52)); + EmSendCmdEx(rATQA, sizeof(rATQA), (receivedCmd[0] == ISO14443A_CMD_WUPA)); cardSTATE = MFEMUL_SELECT1; // init crypto block @@ -2329,6 +2541,9 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * LED_C_OFF(); crypto1_destroy(pcs); cardAUTHKEY = 0xff; + if (flags & FLAG_RANDOM_NONCE) { + nonce = prand(); + } continue; } @@ -2340,59 +2555,141 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * break; } case MFEMUL_SELECT1:{ - // select all - if (len == 2 && (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x20)) { + // select all - 0x93 0x20 + if (len == 2 && (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT && receivedCmd[1] == 0x20)) { if (MF_DBGLEVEL >= 4) Dbprintf("SELECT ALL received"); EmSendCmd(rUIDBCC1, sizeof(rUIDBCC1)); break; } - if (MF_DBGLEVEL >= 4 && len == 9 && receivedCmd[0] == 0x93 && receivedCmd[1] == 0x70 ) - { - Dbprintf("SELECT %02x%02x%02x%02x received",receivedCmd[2],receivedCmd[3],receivedCmd[4],receivedCmd[5]); + // select card - 0x93 0x70 ... + if (len == 9 && + (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC1, 4) == 0)) { + if (MF_DBGLEVEL >= 4) + Dbprintf("SELECT %02x%02x%02x%02x received",receivedCmd[2],receivedCmd[3],receivedCmd[4],receivedCmd[5]); + + switch(_UID_LEN) { + case 4: + cardSTATE = MFEMUL_WORK; + LED_B_ON(); + if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol1 time: %d", GetTickCount() - selTimer); + EmSendCmd(rSAKfinal, sizeof(rSAKfinal)); + break; + case 7: + cardSTATE = MFEMUL_SELECT2; + EmSendCmd(rSAK1, sizeof(rSAK1)); + break; + case 10: + cardSTATE = MFEMUL_SELECT2; + EmSendCmd(rSAK1, sizeof(rSAK1)); + break; + default:break; + } + } else { + cardSTATE_TO_IDLE(); } - // select card + break; + } + case MFEMUL_SELECT3:{ + if (!len) { + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE); + break; + } + // select all cl3 - 0x97 0x20 + if (len == 2 && (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_3 && receivedCmd[1] == 0x20)) { + EmSendCmd(rUIDBCC3, sizeof(rUIDBCC3)); + break; + } + // select card cl3 - 0x97 0x70 if (len == 9 && - (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC1, 4) == 0)) { - EmSendCmd(_7BUID?rSAK1:rSAK, _7BUID?sizeof(rSAK1):sizeof(rSAK)); - cuid = bytes_to_num(rUIDBCC1, 4); - if (!_7BUID) { - cardSTATE = MFEMUL_WORK; - LED_B_ON(); - if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol1 time: %d", GetTickCount() - selTimer); - break; - } else { - cardSTATE = MFEMUL_SELECT2; - } + (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_3 && + receivedCmd[1] == 0x70 && + memcmp(&receivedCmd[2], rUIDBCC3, 4) == 0) ) { + + EmSendCmd(rSAKfinal, sizeof(rSAKfinal)); + cardSTATE = MFEMUL_WORK; + LED_B_ON(); + if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol3 time: %d", GetTickCount() - selTimer); + break; } + cardSTATE_TO_IDLE(); break; } case MFEMUL_AUTH1:{ - if( len != 8) - { + if( len != 8) { cardSTATE_TO_IDLE(); LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE); break; } - uint32_t ar = bytes_to_num(receivedCmd, 4); - uint32_t nr = bytes_to_num(&receivedCmd[4], 4); - - //Collect AR/NR - if(ar_nr_collected < 2){ - if(ar_nr_responses[2] != ar) - {// Avoid duplicates... probably not necessary, ar should vary. - ar_nr_responses[ar_nr_collected*4] = cuid; - ar_nr_responses[ar_nr_collected*4+1] = nonce; - ar_nr_responses[ar_nr_collected*4+2] = ar; - ar_nr_responses[ar_nr_collected*4+3] = nr; - ar_nr_collected++; + uint32_t nr = bytes_to_num(receivedCmd, 4); + uint32_t ar = bytes_to_num(&receivedCmd[4], 4); + + // Collect AR/NR per keytype & sector + if(flags & FLAG_NR_AR_ATTACK) { + for (uint8_t i = 0; i < ATTACK_KEY_COUNT; i++) { + if ( ar_nr_collected[i+mM]==0 || ((cardAUTHSC == ar_nr_resp[i+mM].sector) && (cardAUTHKEY == ar_nr_resp[i+mM].keytype) && (ar_nr_collected[i+mM] > 0)) ) { + // if first auth for sector, or matches sector and keytype of previous auth + if (ar_nr_collected[i+mM] < 2) { + // if we haven't already collected 2 nonces for this sector + if (ar_nr_resp[ar_nr_collected[i+mM]].ar != ar) { + // Avoid duplicates... probably not necessary, ar should vary. + if (ar_nr_collected[i+mM]==0) { + // first nonce collect + ar_nr_resp[i+mM].cuid = cuid; + ar_nr_resp[i+mM].sector = cardAUTHSC; + ar_nr_resp[i+mM].keytype = cardAUTHKEY; + ar_nr_resp[i+mM].nonce = nonce; + ar_nr_resp[i+mM].nr = nr; + ar_nr_resp[i+mM].ar = ar; + nonce1_count++; + // add this nonce to first moebius nonce + ar_nr_resp[i+ATTACK_KEY_COUNT].cuid = cuid; + ar_nr_resp[i+ATTACK_KEY_COUNT].sector = cardAUTHSC; + ar_nr_resp[i+ATTACK_KEY_COUNT].keytype = cardAUTHKEY; + ar_nr_resp[i+ATTACK_KEY_COUNT].nonce = nonce; + ar_nr_resp[i+ATTACK_KEY_COUNT].nr = nr; + ar_nr_resp[i+ATTACK_KEY_COUNT].ar = ar; + ar_nr_collected[i+ATTACK_KEY_COUNT]++; + } else { // second nonce collect (std and moebius) + ar_nr_resp[i+mM].nonce2 = nonce; + ar_nr_resp[i+mM].nr2 = nr; + ar_nr_resp[i+mM].ar2 = ar; + if (!gettingMoebius) { + nonce2_count++; + // check if this was the last second nonce we need for std attack + if ( nonce2_count == nonce1_count ) { + // done collecting std test switch to moebius + // first finish incrementing last sample + ar_nr_collected[i+mM]++; + // switch to moebius collection + gettingMoebius = true; + mM = ATTACK_KEY_COUNT; + if (flags & FLAG_RANDOM_NONCE) { + nonce = prand(); + } else { + nonce = nonce*7; + } + break; + } + } else { + moebius_n_count++; + // if we've collected all the nonces we need - finish. + if (nonce1_count == moebius_n_count) finished = true; + } + } + ar_nr_collected[i+mM]++; + } + } + // we found right spot for this nonce stop looking + break; + } } } // --- crypto - crypto1_word(pcs, ar , 1); - cardRr = nr ^ crypto1_word(pcs, 0, 0); + crypto1_word(pcs, nr , 1); + cardRr = ar ^ crypto1_word(pcs, 0, 0); // test if auth OK if (cardRr != prng_successor(nonce, 64)){ @@ -2408,6 +2705,7 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * break; } + //auth successful ans = prng_successor(nonce, 96) ^ crypto1_word(pcs, 0, 0); num_to_bytes(ans, 4, rAUTH_AT); @@ -2424,20 +2722,29 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * if (!len) { LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE); break; - } - if (len == 2 && (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x20)) { + } + // select all cl2 - 0x95 0x20 + if (len == 2 && (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2 && receivedCmd[1] == 0x20)) { EmSendCmd(rUIDBCC2, sizeof(rUIDBCC2)); break; } - // select 2 card + // select cl2 card - 0x95 0x70 xxxxxxxxxxxx if (len == 9 && - (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC2, 4) == 0)) { - EmSendCmd(rSAK, sizeof(rSAK)); - cuid = bytes_to_num(rUIDBCC2, 4); - cardSTATE = MFEMUL_WORK; - LED_B_ON(); - if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol2 time: %d", GetTickCount() - selTimer); + (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC2, 4) == 0)) { + switch(_UID_LEN) { + case 7: + EmSendCmd(rSAKfinal, sizeof(rSAKfinal)); + cardSTATE = MFEMUL_WORK; + LED_B_ON(); + if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol2 time: %d", GetTickCount() - selTimer); + break; + case 10: + EmSendCmd(rSAK1, sizeof(rSAK1)); + cardSTATE = MFEMUL_SELECT3; + break; + default:break; + } break; } @@ -2465,11 +2772,22 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * } if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) { + + // if authenticating to a block that shouldn't exist - as long as we are not doing the reader attack + if (receivedCmd[1] >= 16 * 4 && !(flags & FLAG_NR_AR_ATTACK)) { + //is this the correct response to an auth on a out of range block? marshmellow + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02x) on out of range block: %d (0x%02x), nacking",receivedCmd[0],receivedCmd[1],receivedCmd[1]); + break; + } + authTimer = GetTickCount(); cardAUTHSC = receivedCmd[1] / 4; // received block num cardAUTHKEY = receivedCmd[0] - 0x60; crypto1_destroy(pcs);//Added by martin crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY)); + //uint64_t key=emlGetKey(cardAUTHSC, cardAUTHKEY); + //Dbprintf("key: %04x%08x",(uint32_t)(key>>32)&0xFFFF,(uint32_t)(key&0xFFFFFFFF)); if (!encrypted_data) { // first authentication if (MF_DBGLEVEL >= 4) Dbprintf("Reader authenticating for block %d (0x%02x) with key %d",receivedCmd[1] ,receivedCmd[1],cardAUTHKEY ); @@ -2514,13 +2832,13 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * || receivedCmd[0] == 0xB0) { // transfer if (receivedCmd[1] >= 16 * 4) { EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); - if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02) on out of range block: %d (0x%02x), nacking",receivedCmd[0],receivedCmd[1],receivedCmd[1]); + if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02x) on out of range block: %d (0x%02x), nacking",receivedCmd[0],receivedCmd[1],receivedCmd[1]); break; } if (receivedCmd[1] / 4 != cardAUTHSC) { EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); - if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02) on block (0x%02x) not authenticated for (0x%02x), nacking",receivedCmd[0],receivedCmd[1],cardAUTHSC); + if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02x) on block (0x%02x) not authenticated for (0x%02x), nacking",receivedCmd[0],receivedCmd[1],cardAUTHSC); break; } } @@ -2646,45 +2964,48 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * break; } } + button_pushed = BUTTON_PRESS(); } FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); LEDsoff(); - if(flags & FLAG_INTERACTIVE)// Interactive mode flag, means we need to send ACK - { - //May just aswell send the collected ar_nr in the response aswell - cmd_send(CMD_ACK,CMD_SIMULATE_MIFARE_CARD,0,0,&ar_nr_responses,ar_nr_collected*4*4); - } - - if(flags & FLAG_NR_AR_ATTACK) - { - if(ar_nr_collected > 1) { - Dbprintf("Collected two pairs of AR/NR which can be used to extract keys from reader:"); - Dbprintf("../tools/mfkey/mfkey32 %08x %08x %08x %08x %08x %08x", - ar_nr_responses[0], // UID - ar_nr_responses[1], //NT - ar_nr_responses[2], //AR1 - ar_nr_responses[3], //NR1 - ar_nr_responses[6], //AR2 - ar_nr_responses[7] //NR2 - ); - } else { - Dbprintf("Failed to obtain two AR/NR pairs!"); - if(ar_nr_collected >0) { - Dbprintf("Only got these: UID=%08x, nonce=%08x, AR1=%08x, NR1=%08x", - ar_nr_responses[0], // UID - ar_nr_responses[1], //NT - ar_nr_responses[2], //AR1 - ar_nr_responses[3] //NR1 + if(flags & FLAG_NR_AR_ATTACK && MF_DBGLEVEL >= 1) { + for ( uint8_t i = 0; i < ATTACK_KEY_COUNT; i++) { + if (ar_nr_collected[i] == 2) { + Dbprintf("Collected two pairs of AR/NR which can be used to extract %s from reader for sector %d:", (i= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, BigBuf_get_traceLen()); - -} + if(flags & FLAG_INTERACTIVE) { // Interactive mode flag, means we need to send ACK + //Send the collected ar_nr in the response + cmd_send(CMD_ACK,CMD_SIMULATE_MIFARE_CARD,button_pushed,0,&ar_nr_resp,sizeof(ar_nr_resp)); + } +} //----------------------------------------------------------------------------- @@ -2711,10 +3032,8 @@ void RAMFUNC SniffMifare(uint8_t param) { uint8_t receivedResponse[MAX_MIFARE_FRAME_SIZE]; uint8_t receivedResponsePar[MAX_MIFARE_PARITY_SIZE]; - // As we receive stuff, we copy it from receivedCmd or receivedResponse - // into trace, along with its length and other annotations. - //uint8_t *trace = (uint8_t *)BigBuf; - + iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER); + // free eventually allocated BigBuf memory BigBuf_free(); // allocate the DMA buffer, used to stream samples from the FPGA @@ -2726,8 +3045,6 @@ void RAMFUNC SniffMifare(uint8_t param) { bool ReaderIsActive = FALSE; bool TagIsActive = FALSE; - iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER); - // Set up the demodulator for tag -> reader responses. DemodInit(receivedResponse, receivedResponsePar); @@ -2824,6 +3141,8 @@ void RAMFUNC SniffMifare(uint8_t param) { // And ready to receive another response. DemodReset(); + // And reset the Miller decoder including its (now outdated) input buffer + UartInit(receivedCmd, receivedCmdPar); } TagIsActive = (Demod.state != DEMOD_UNSYNCD); }