From 91c7a7ccb72641f957d41e2c6b081a5ddec57f74 Mon Sep 17 00:00:00 2001 From: iceman1001 Date: Tue, 12 Apr 2016 11:36:52 +0200 Subject: [PATCH] Syntaxt suger, and some clean up in the "hf mf mifare" code. I removed the three strategies Pivi added to make the code easier and added a lot of comments to understand. the WDT bug is still there in this code. Needs further testing yet, before I commit the fix. So far the fix is quite stable on ubuntu, but on mingw/win is breaking still. Which at this point doesnt make any sense. --- armsrc/iso14443a.c | 414 +++++++++++++++++++-------------------------- 1 file changed, 176 insertions(+), 238 deletions(-) diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c index ef10b033..436065fb 100644 --- a/armsrc/iso14443a.c +++ b/armsrc/iso14443a.c @@ -132,7 +132,6 @@ void iso14a_set_timeout(uint32_t timeout) { } void iso14a_set_ATS_timeout(uint8_t *ats) { - uint8_t tb1; uint8_t fwi; uint32_t fwt; @@ -159,8 +158,7 @@ void iso14a_set_ATS_timeout(uint8_t *ats) { // Generate the parity value for a byte sequence // //----------------------------------------------------------------------------- -void GetParity(const uint8_t *pbtCmd, uint16_t iLen, uint8_t *par) -{ +void GetParity(const uint8_t *pbtCmd, uint16_t iLen, uint8_t *par) { uint16_t paritybit_cnt = 0; uint16_t paritybyte_cnt = 0; uint8_t parityBits = 0; @@ -179,12 +177,10 @@ void GetParity(const uint8_t *pbtCmd, uint16_t iLen, uint8_t *par) } // save remaining parity bits - par[paritybyte_cnt] = parityBits; - + par[paritybyte_cnt] = parityBits; } -void AppendCrc14443a(uint8_t* data, int len) -{ +void AppendCrc14443a(uint8_t* data, int len) { ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1); } @@ -219,8 +215,7 @@ const bool Mod_Miller_LUT[] = { #define IsMillerModulationNibble1(b) (Mod_Miller_LUT[(b & 0x000000F0) >> 4]) #define IsMillerModulationNibble2(b) (Mod_Miller_LUT[(b & 0x0000000F)]) -void UartReset() -{ +void UartReset() { Uart.state = STATE_UNSYNCD; Uart.bitCount = 0; Uart.len = 0; // number of decoded data bytes @@ -235,8 +230,7 @@ void UartReset() Uart.syncBit = 9999; } -void UartInit(uint8_t *data, uint8_t *parity) -{ +void UartInit(uint8_t *data, uint8_t *parity) { Uart.output = data; Uart.parity = parity; Uart.fourBits = 0x00000000; // clear the buffer for 4 Bits @@ -244,14 +238,11 @@ void UartInit(uint8_t *data, uint8_t *parity) } // use parameter non_real_time to provide a timestamp. Set to 0 if the decoder should measure real time -static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) -{ - +static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) { Uart.fourBits = (Uart.fourBits << 8) | bit; if (Uart.state == STATE_UNSYNCD) { // not yet synced - - Uart.syncBit = 9999; // not set + Uart.syncBit = 9999; // not set // 00x11111 2|3 ticks pause followed by 6|5 ticks unmodulated Sequence Z (a "0" or "start of communication") // 11111111 8 ticks unmodulation Sequence Y (a "0" or "end of communication" or "no information") @@ -275,12 +266,11 @@ static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 7)) == ISO14443A_STARTBIT_PATTERN >> 7) Uart.syncBit = 0; if (Uart.syncBit != 9999) { // found a sync bit - Uart.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8); - Uart.startTime -= Uart.syncBit; - Uart.endTime = Uart.startTime; - Uart.state = STATE_START_OF_COMMUNICATION; - } - + Uart.startTime = non_real_time ? non_real_time : (GetCountSspClk() & 0xfffffff8); + Uart.startTime -= Uart.syncBit; + Uart.endTime = Uart.startTime; + Uart.state = STATE_START_OF_COMMUNICATION; + } } else { if (IsMillerModulationNibble1(Uart.fourBits >> Uart.syncBit)) { @@ -366,9 +356,7 @@ static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) } } } - } - return FALSE; // not finished yet, need more data } @@ -401,9 +389,7 @@ const bool Mod_Manchester_LUT[] = { #define IsManchesterModulationNibble1(b) (Mod_Manchester_LUT[(b & 0x00F0) >> 4]) #define IsManchesterModulationNibble2(b) (Mod_Manchester_LUT[(b & 0x000F)]) - -void DemodReset() -{ +void DemodReset() { Demod.state = DEMOD_UNSYNCD; Demod.len = 0; // number of decoded data bytes Demod.parityLen = 0; @@ -413,24 +399,20 @@ void DemodReset() Demod.twoBits = 0xffff; // buffer for 2 Bits Demod.highCnt = 0; Demod.startTime = 0; - Demod.endTime = 0; - - // + Demod.endTime = 0; Demod.bitCount = 0; Demod.syncBit = 0xFFFF; Demod.samples = 0; } -void DemodInit(uint8_t *data, uint8_t *parity) -{ +void DemodInit(uint8_t *data, uint8_t *parity) { Demod.output = data; Demod.parity = parity; DemodReset(); } // use parameter non_real_time to provide a timestamp. Set to 0 if the decoder should measure real time -static RAMFUNC int ManchesterDecoding(uint8_t bit, uint16_t offset, uint32_t non_real_time) -{ +static RAMFUNC int ManchesterDecoding(uint8_t bit, uint16_t offset, uint32_t non_real_time) { Demod.twoBits = (Demod.twoBits << 8) | bit; if (Demod.state == DEMOD_UNSYNCD) { @@ -458,7 +440,6 @@ static RAMFUNC int ManchesterDecoding(uint8_t bit, uint16_t offset, uint32_t non Demod.state = DEMOD_MANCHESTER_DATA; } } - } else { if (IsManchesterModulationNibble1(Demod.twoBits >> Demod.syncBit)) { // modulation in first half @@ -541,8 +522,6 @@ void RAMFUNC SniffIso14443a(uint8_t param) { // Allocate memory from BigBuf for some buffers // free all previous allocations first BigBuf_free(); BigBuf_Clear_ext(false); - - // init trace buffer clear_trace(); set_tracing(TRUE); @@ -667,7 +646,6 @@ void RAMFUNC SniffIso14443a(uint8_t param) { DemodReset(); // And reset the Miller decoder including itS (now outdated) input buffer UartInit(receivedCmd, receivedCmdPar); - LED_C_OFF(); } TagIsActive = (Demod.state != DEMOD_UNSYNCD); @@ -688,14 +666,14 @@ void RAMFUNC SniffIso14443a(uint8_t param) { Dbprintf("maxDataLen=%d, Uart.state=%x, Uart.len=%d", maxDataLen, Uart.state, Uart.len); Dbprintf("traceLen=%d, Uart.output[0]=%08x", BigBuf_get_traceLen(), (uint32_t)Uart.output[0]); + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); set_tracing(FALSE); } //----------------------------------------------------------------------------- // Prepare tag messages //----------------------------------------------------------------------------- -static void CodeIso14443aAsTagPar(const uint8_t *cmd, uint16_t len, uint8_t *parity) -{ +static void CodeIso14443aAsTagPar(const uint8_t *cmd, uint16_t len, uint8_t *parity) { ToSendReset(); // Correction bit, might be removed when not needed @@ -742,17 +720,15 @@ static void CodeIso14443aAsTagPar(const uint8_t *cmd, uint16_t len, uint8_t *par ++ToSendMax; } -static void CodeIso14443aAsTag(const uint8_t *cmd, uint16_t len) -{ +static void CodeIso14443aAsTag(const uint8_t *cmd, uint16_t len) { uint8_t par[MAX_PARITY_SIZE] = {0}; GetParity(cmd, len, par); CodeIso14443aAsTagPar(cmd, len, par); } - -static void Code4bitAnswerAsTag(uint8_t cmd) -{ +static void Code4bitAnswerAsTag(uint8_t cmd) { int i; + uint8_t b = cmd; ToSendReset(); @@ -769,7 +745,6 @@ static void Code4bitAnswerAsTag(uint8_t cmd) // Send startbit ToSend[++ToSendMax] = SEC_D; - uint8_t b = cmd; for(i = 0; i < 4; i++) { if(b & 1) { ToSend[++ToSendMax] = SEC_D; @@ -793,8 +768,7 @@ static void Code4bitAnswerAsTag(uint8_t cmd) // Stop when button is pressed // Or return TRUE when command is captured //----------------------------------------------------------------------------- -static int GetIso14443aCommandFromReader(uint8_t *received, uint8_t *parity, int *len) -{ +static int GetIso14443aCommandFromReader(uint8_t *received, uint8_t *parity, int *len) { // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen // only, since we are receiving, not transmitting). // Signal field is off with the appropriate LED @@ -853,26 +827,23 @@ bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffe // ----------- + // 166 bytes, since every bit that needs to be send costs us a byte // - - - // Prepare the tag modulation bits from the message - CodeIso14443aAsTag(response_info->response,response_info->response_n); - - // Make sure we do not exceed the free buffer space - if (ToSendMax > max_buffer_size) { - Dbprintf("Out of memory, when modulating bits for tag answer:"); - Dbhexdump(response_info->response_n,response_info->response,false); - return false; - } - - // Copy the byte array, used for this modulation to the buffer position - memcpy(response_info->modulation,ToSend,ToSendMax); - - // Store the number of bytes that were used for encoding/modulation and the time needed to transfer them - response_info->modulation_n = ToSendMax; - response_info->ProxToAirDuration = LastProxToAirDuration; - - return true; + // Prepare the tag modulation bits from the message + CodeIso14443aAsTag(response_info->response,response_info->response_n); + + // Make sure we do not exceed the free buffer space + if (ToSendMax > max_buffer_size) { + Dbprintf("Out of memory, when modulating bits for tag answer:"); + Dbhexdump(response_info->response_n,response_info->response,false); + return FALSE; + } + + // Copy the byte array, used for this modulation to the buffer position + memcpy(response_info->modulation,ToSend,ToSendMax); + + // Store the number of bytes that were used for encoding/modulation and the time needed to transfer them + response_info->modulation_n = ToSendMax; + response_info->ProxToAirDuration = LastProxToAirDuration; + return TRUE; } @@ -905,8 +876,7 @@ bool prepare_allocated_tag_modulation(tag_response_info_t* response_info) { // Main loop of simulated tag: receive commands from reader, decide what // response to send, and send it. //----------------------------------------------------------------------------- -void SimulateIso14443aTag(int tagType, int flags, byte_t* data) -{ +void SimulateIso14443aTag(int tagType, int flags, byte_t* data) { uint32_t counters[] = {0,0,0}; //Here, we collect UID,NT,AR,NR,UID2,NT2,AR2,NR2 // This can be used in a reader-only attack. @@ -1148,25 +1118,23 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) // We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below p_response = NULL; } - } else if(receivedCmd[0] == 0x3A) { // Received a FAST READ (ranged read) - - uint8_t emdata[MAX_FRAME_SIZE]; - //first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature] - int start = (receivedCmd[1]+12) * 4; - int len = (receivedCmd[2] - receivedCmd[1] + 1) * 4; - emlGetMemBt( emdata, start, len); - AppendCrc14443a(emdata, len); - EmSendCmdEx(emdata, len+2, false); - p_response = NULL; - + } else if(receivedCmd[0] == 0x3A) { // Received a FAST READ (ranged read) + uint8_t emdata[MAX_FRAME_SIZE]; + //first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature] + int start = (receivedCmd[1]+12) * 4; + int len = (receivedCmd[2] - receivedCmd[1] + 1) * 4; + emlGetMemBt( emdata, start, len); + AppendCrc14443a(emdata, len); + EmSendCmdEx(emdata, len+2, false); + p_response = NULL; } else if(receivedCmd[0] == 0x3C && tagType == 7) { // Received a READ SIGNATURE -- - //first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature] - uint16_t start = 4 * 4; - uint8_t emdata[34]; - emlGetMemBt( emdata, start, 32); - AppendCrc14443a(emdata, 32); - EmSendCmdEx(emdata, sizeof(emdata), false); - p_response = NULL; + //first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature] + uint16_t start = 4 * 4; + uint8_t emdata[34]; + emlGetMemBt( emdata, start, 32); + AppendCrc14443a(emdata, 32); + EmSendCmdEx(emdata, sizeof(emdata), false); + p_response = NULL; } else if (receivedCmd[0] == 0x39 && tagType == 7) { // Received a READ COUNTER -- uint8_t index = receivedCmd[1]; uint8_t data[] = {0x00,0x00,0x00,0x14,0xa5}; @@ -1185,8 +1153,7 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) // send ACK uint8_t ack[] = {0x0a}; EmSendCmdEx(ack,sizeof(ack),false); - p_response = NULL; - + p_response = NULL; } else if(receivedCmd[0] == 0x3E && tagType == 7) { // Received a CHECK_TEARING_EVENT -- //first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature] uint8_t emdata[3]; @@ -1222,10 +1189,8 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) uint32_t nonce = bytes_to_num(response5,4); uint32_t nr = bytes_to_num(receivedCmd,4); uint32_t ar = bytes_to_num(receivedCmd+4,4); - //Dbprintf("Auth attempt {nonce}{nr}{ar}: %08x %08x %08x", nonce, nr, ar); - if(flags & FLAG_NR_AR_ATTACK ) - { + if(flags & FLAG_NR_AR_ATTACK ) { if(ar_nr_collected < 2){ // Avoid duplicates... probably not necessary, nr should vary. //if(ar_nr_responses[3] != nr){ @@ -1268,12 +1233,9 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) memset(ar_nr_responses, 0x00, len); } } - } else if (receivedCmd[0] == 0x1a ) // ULC authentication - { - + } else if (receivedCmd[0] == 0x1a ) { // ULC authentication } - else if (receivedCmd[0] == 0x1b) // NTAG / EV-1 authentication - { + else if (receivedCmd[0] == 0x1b) { // NTAG / EV-1 authentication if ( tagType == 7 ) { uint16_t start = 13; //first 4 blocks of emu are [getversion answer - check tearing - pack - 0x00] uint8_t emdata[4]; @@ -1283,7 +1245,7 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) p_response = NULL; uint32_t pwd = bytes_to_num(receivedCmd+1,4); - if ( MF_DBGLEVEL >= 3) Dbprintf("Auth attempt: %08x", pwd); + if ( MF_DBGLEVEL >= 3) Dbprintf("Auth attempt: %08x", pwd); } } else { // Check for ISO 14443A-4 compliant commands, look at left nibble @@ -1362,6 +1324,7 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) // Count number of other messages after a halt if(order != 6 && lastorder == 5) { happened2++; } + // comment this limit if you want to simulation longer if(cmdsRecvd > 999) { DbpString("1000 commands later..."); break; @@ -1385,7 +1348,8 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) (LastTimeProxToAirStart + p_response->ProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG, par); } - + + // comment this limit if you want to simulation longer if (!tracing) { Dbprintf("Trace Full. Simulation stopped."); break; @@ -1856,11 +1820,10 @@ int ReaderReceiveOffset(uint8_t* receivedAnswer, uint16_t offset, uint8_t *parit return Demod.len; } -int ReaderReceive(uint8_t *receivedAnswer, uint8_t *parity) -{ +int ReaderReceive(uint8_t *receivedAnswer, uint8_t *parity) { if (!GetIso14443aAnswerFromTag(receivedAnswer, parity, 0)) return FALSE; //if (tracing) { - LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, parity, FALSE); + LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, parity, FALSE); //} return Demod.len; } @@ -2028,6 +1991,8 @@ void iso14443a_setup(uint8_t fpga_minor_mode) { FpgaSetupSsc(); // connect Demodulated Signal to ADC: SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | fpga_minor_mode); LED_D_OFF(); // Signal field is on with the appropriate LED @@ -2035,17 +2000,17 @@ void iso14443a_setup(uint8_t fpga_minor_mode) { fpga_minor_mode == FPGA_HF_ISO14443A_READER_LISTEN) LED_D_ON(); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | fpga_minor_mode); - + // Prepare the demodulation functions DemodReset(); UartReset(); iso14a_set_timeout(10*106); // 10ms default + + //NextTransferTime = 2 * DELAY_ARM2AIR_AS_READER; + NextTransferTime = DELAY_ARM2AIR_AS_READER << 1; // Start the timer StartCountSspClk(); - - NextTransferTime = 2*DELAY_ARM2AIR_AS_READER; } int iso14_apdu(uint8_t *cmd, uint16_t cmd_len, void *data) { @@ -2082,13 +2047,12 @@ int iso14_apdu(uint8_t *cmd, uint16_t cmd_len, void *data) { // Read an ISO 14443a tag. Send out commands and store answers. // //----------------------------------------------------------------------------- -void ReaderIso14443a(UsbCommand *c) -{ +void ReaderIso14443a(UsbCommand *c) { iso14a_command_t param = c->arg[0]; - uint8_t *cmd = c->d.asBytes; size_t len = c->arg[1] & 0xffff; size_t lenbits = c->arg[1] >> 16; uint32_t timeout = c->arg[2]; + uint8_t *cmd = c->d.asBytes; uint32_t arg0 = 0; byte_t buf[USB_CMD_DATA_SIZE] = {0x00}; uint8_t par[MAX_PARITY_SIZE] = {0x00}; @@ -2106,7 +2070,7 @@ void ReaderIso14443a(UsbCommand *c) if(!(param & ISO14A_NO_SELECT)) { iso14a_card_select_t *card = (iso14a_card_select_t*)buf; arg0 = iso14443a_select_card(NULL,card,NULL, true, 0); - cmd_send(CMD_ACK,arg0,card->uidlen,0,buf,sizeof(iso14a_card_select_t)); + cmd_send(CMD_ACK, arg0, card->uidlen, 0, buf, sizeof(iso14a_card_select_t)); // if it fails, the cmdhf14a.c client quites.. however this one still executes. if ( arg0 == 0 ) return; } @@ -2162,7 +2126,6 @@ void ReaderIso14443a(UsbCommand *c) if (param & ISO14A_REQUEST_TRIGGER) iso14a_set_trigger(FALSE); - if (param & ISO14A_NO_DISCONNECT) return; @@ -2177,22 +2140,20 @@ void ReaderIso14443a(UsbCommand *c) // Therefore try in alternating directions. int32_t dist_nt(uint32_t nt1, uint32_t nt2) { - uint16_t i; - uint32_t nttmp1, nttmp2; - if (nt1 == nt2) return 0; - - nttmp1 = nt1; - nttmp2 = nt2; - for (i = 1; i < 32768; i++) { + uint16_t i; + uint32_t nttmp1 = nt1; + uint32_t nttmp2 = nt2; + + for (i = 1; i < 32768; ++i) { nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i; nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -i; - } - - return(-99999); // either nt1 or nt2 are invalid nonces + } + // either nt1 or nt2 are invalid nonces + return(-99999); } @@ -2202,12 +2163,11 @@ int32_t dist_nt(uint32_t nt1, uint32_t nt2) { // Cloning MiFare Classic Rail and Building Passes, Anywhere, Anytime" // (article by Nicolas T. Courtois, 2009) //----------------------------------------------------------------------------- -void ReaderMifare(bool first_try, uint8_t block ) -{ +void ReaderMifare(bool first_try, uint8_t block ) { // Mifare AUTH //uint8_t mf_auth[] = { 0x60,0x00,0xf5,0x7b }; //uint8_t mf_auth[] = { 0x60,0x05, 0x58, 0x2c }; - uint8_t mf_auth[] = { 0x60,0x00, 0x00, 0x00 }; + uint8_t mf_auth[] = { MIFARE_AUTH_KEYA, block, 0x00, 0x00 }; uint8_t mf_nr_ar[] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }; uint8_t uid[10] = {0,0,0,0,0,0,0,0,0,0}; uint8_t par_list[8] = {0,0,0,0,0,0,0,0}; @@ -2215,55 +2175,48 @@ void ReaderMifare(bool first_try, uint8_t block ) uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE] = {0x00}; uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE] = {0x00}; uint8_t par[1] = {0}; // maximum 8 Bytes to be sent here, 1 byte parity is therefore enough - - mf_auth[1] = block; - AppendCrc14443a(mf_auth, 2); - byte_t nt_diff = 0; - uint32_t nt = 0; uint32_t previous_nt = 0; - uint32_t halt_time = 0; uint32_t cuid = 0; - int catch_up_cycles = 0; - int last_catch_up = 0; - int isOK = 0; + int32_t catch_up_cycles = 0; + int32_t last_catch_up = 0; + int32_t isOK = 0; + int32_t nt_distance = 0; uint16_t elapsed_prng_sequences = 1; uint16_t consecutive_resyncs = 0; uint16_t unexpected_random = 0; uint16_t sync_tries = 0; - uint16_t strategy = 0; + // static variables here, is re-used in the next call? static uint32_t nt_attacked = 0; static uint32_t sync_time = 0; - static int32_t sync_cycles = 0; + static uint32_t sync_cycles = 0; static uint8_t par_low = 0; static uint8_t mf_nr_ar3 = 0; - + #define PRNG_SEQUENCE_LENGTH (1 << 16) #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 MAX_STRATEGY 3 - // free eventually allocated BigBuf memory - BigBuf_free(); BigBuf_Clear_ext(false); - + BigBuf_free(); BigBuf_Clear_ext(false); clear_trace(); - set_tracing(TRUE); - - LED_A_ON(); - - if (first_try) - iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD); + set_tracing(TRUE); + iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD); + AppendCrc14443a(mf_auth, 2); + if (first_try) { sync_time = GetCountSspClk() & 0xfffffff8; - sync_cycles = PRNG_SEQUENCE_LENGTH + 1100; //65536; //0x10000 // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces). + sync_cycles = PRNG_SEQUENCE_LENGTH + 1130; //65536; //0x10000 // Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces). mf_nr_ar3 = 0; nt_attacked = 0; + par_low = 0; + Dbprintf("FIRST: sync_time - %08X", sync_time); } else { // we were unsuccessful on a previous call. // Try another READER nonce (first 3 parity bits remain the same) @@ -2271,10 +2224,13 @@ void ReaderMifare(bool first_try, uint8_t block ) mf_nr_ar[3] = mf_nr_ar3; par[0] = par_low; } - - LED_A_ON(); + + bool have_uid = FALSE; + uint8_t cascade_levels = 0; + LED_C_ON(); - for(uint16_t i = 0; TRUE; ++i) { + uint16_t i; + for(i = 0; TRUE; ++i) { WDT_HIT(); @@ -2284,98 +2240,98 @@ void ReaderMifare(bool first_try, uint8_t block ) break; } - if (strategy == 2) { - // test with additional halt 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 halt command.", 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); - sync_time = GetCountSspClk() & 0xfffffff8; - WDT_HIT(); - } - - if (!iso14443a_select_card(uid, NULL, &cuid, true, 0)) { - if (MF_DBGLEVEL >= 2) Dbprintf("Mifare: Can't select card\n"); - continue; + // this part is from Piwi's faster nonce collecting part in Hardnested. + if (!have_uid) { // need a full select cycle to get the uid first + iso14a_card_select_t card_info; + if(!iso14443a_select_card(uid, &card_info, &cuid, true, 0)) { + if (MF_DBGLEVEL >= 4) Dbprintf("Mifare: Can't select card (ALL)"); + break; + } + switch (card_info.uidlen) { + case 4 : cascade_levels = 1; break; + case 7 : cascade_levels = 2; break; + case 10: cascade_levels = 3; break; + default: break; + } + have_uid = TRUE; + } else { // no need for anticollision. We can directly select the card + if(!iso14443a_select_card(uid, NULL, &cuid, false, cascade_levels)) { + if (MF_DBGLEVEL >= 4) Dbprintf("Mifare: Can't select card (UID)"); + continue; + } } - - // Sending timeslot of ISO14443a frame - sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles; + // Sending timeslot of ISO14443a frame + sync_time = (sync_time & 0xfffffff8 ) + sync_cycles + catch_up_cycles; catch_up_cycles = 0; - - //catch_up_cycles = 0; // if we missed the sync time already, advance to the next nonce repeat - while(GetCountSspClk() > sync_time) { + 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); + 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); - // Receive the (4 Byte) "random" nonce + // Receive the (4 Byte) "random" nonce from TAG if (!ReaderReceive(receivedAnswer, receivedAnswerPar)) continue; - // Transmit reader nonce with fake par - ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar), par, NULL); - previous_nt = nt; nt = bytes_to_num(receivedAnswer, 4); + // Transmit reader nonce with fake par + ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar), par, NULL); + + WDT_HIT(); + LED_B_ON(); if (first_try && previous_nt && !nt_attacked) { // we didn't calibrate our clock yet - int nt_distance = dist_nt(previous_nt, nt); + + nt_distance = dist_nt(previous_nt, nt); + + // if no distance between, then we are in sync. if (nt_distance == 0) { nt_attacked = nt; } else { if (nt_distance == -99999) { // invalid nonce received - unexpected_random++; + ++unexpected_random; if (unexpected_random > MAX_UNEXPECTED_RANDOM) { isOK = -3; // Card has an unpredictable PRNG. Give up break; - } else { + } else { + if (sync_cycles <= 0) sync_cycles += PRNG_SEQUENCE_LENGTH; + LED_B_OFF(); 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; - } + isOK = -4; // Card's PRNG runs at an unexpected frequency or resets unexpectedly + break; } sync_cycles = (sync_cycles - nt_distance)/elapsed_prng_sequences; + if (sync_cycles <= 0) sync_cycles += PRNG_SEQUENCE_LENGTH; - if (MF_DBGLEVEL >= 3) + if (MF_DBGLEVEL >= 4) 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); + LED_B_OFF(); continue; } } + LED_B_OFF(); if ((nt != nt_attacked) && nt_attacked) { // we somehow lost sync. Try to catch up again... - catch_up_cycles = -dist_nt(nt_attacked, nt); + catch_up_cycles = ABS(dist_nt(nt_attacked, nt)); if (catch_up_cycles == 99999) { // invalid nonce received. Don't resync on that one. catch_up_cycles = 0; continue; - } - + } // average? catch_up_cycles /= elapsed_prng_sequences; @@ -2387,13 +2343,13 @@ void ReaderMifare(bool first_try, uint8_t block ) } if (consecutive_resyncs < 3) { - if (MF_DBGLEVEL >= 3) - Dbprintf("Lost sync in cycle %d. nt_distance=%d. Consecutive Resyncs = %d. Trying one time catch up...\n", i, -catch_up_cycles, consecutive_resyncs); + if (MF_DBGLEVEL >= 4) + Dbprintf("Lost sync in cycle %d. nt_distance=%d. Consecutive Resyncs = %d. Trying one time catch up...\n", i, catch_up_cycles, consecutive_resyncs); } else { 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); + if (MF_DBGLEVEL >= 4) + 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; @@ -2403,14 +2359,14 @@ void ReaderMifare(bool first_try, uint8_t block ) } // 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) 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 par_list[nt_diff] = SwapBits(par[0], 8); - ks_list[nt_diff] = receivedAnswer[0] ^ 0x05; + ks_list[nt_diff] = receivedAnswer[0] ^ 0x05; // xor with NACK value to get keystream // Test if the information is complete if (nt_diff == 0x07) { @@ -2436,30 +2392,23 @@ void ReaderMifare(bool first_try, uint8_t block ) } } + // reset the resyncs since we got a complete transaction on right time. consecutive_resyncs = 0; - } + } // end for loop mf_nr_ar[3] &= 0x1F; - WDT_HIT(); - - // reset sync_time. - if ( isOK == 1) { - sync_time = 0; - sync_cycles = 0; - mf_nr_ar3 = 0; - nt_attacked = 0; - par[0] = 0; - } + if (MF_DBGLEVEL >= 1) Dbprintf("\nNumber of sent auth requestes: %u", i); uint8_t buf[28] = {0x00}; + memset(buf, 0x00, sizeof(buf)); num_to_bytes(cuid, 4, buf); num_to_bytes(nt, 4, buf + 4); memcpy(buf + 8, par_list, 8); 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, sizeof(buf) ); FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); LEDsoff(); @@ -2476,8 +2425,7 @@ void ReaderMifare(bool first_try, uint8_t block ) * 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 */ -void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *datain) -{ +void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *datain) { int cardSTATE = MFEMUL_NOFIELD; int _7BUID = 0; int vHf = 0; // in mV @@ -2951,9 +2899,6 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * } } - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - LEDsoff(); - // Interactive mode flag, means we need to send ACK if(flags & FLAG_INTERACTIVE) { //May just aswell send the collected ar_nr in the response aswell @@ -2998,6 +2943,8 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * } if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, BigBuf_get_traceLen()); + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); set_tracing(FALSE); } @@ -3014,14 +2961,10 @@ void RAMFUNC SniffMifare(uint8_t param) { // free eventually allocated BigBuf memory BigBuf_free(); BigBuf_Clear_ext(false); - - // init trace buffer clear_trace(); set_tracing(TRUE); // The command (reader -> tag) that we're receiving. - // The length of a received command will in most cases be no more than 18 bytes. - // So 32 should be enough! uint8_t receivedCmd[MAX_MIFARE_FRAME_SIZE] = {0x00}; uint8_t receivedCmdPar[MAX_MIFARE_PARITY_SIZE] = {0x00}; @@ -3056,15 +2999,15 @@ void RAMFUNC SniffMifare(uint8_t param) { // And now we loop, receiving samples. for(uint32_t sniffCounter = 0; TRUE; ) { + + LED_A_ON(); + WDT_HIT(); if(BUTTON_PRESS()) { DbpString("cancelled by button"); break; } - - LED_A_ON(); - WDT_HIT(); - + if ((sniffCounter & 0x0000FFFF) == 0) { // from time to time // check if a transaction is completed (timeout after 2000ms). // if yes, stop the DMA transfer and send what we have so far to the client @@ -3101,7 +3044,7 @@ void RAMFUNC SniffMifare(uint8_t param) { if (!AT91C_BASE_PDC_SSC->PDC_RCR) { AT91C_BASE_PDC_SSC->PDC_RPR = (uint32_t) dmaBuf; AT91C_BASE_PDC_SSC->PDC_RCR = DMA_BUFFER_SIZE; - Dbprintf("RxEmpty ERROR!!! data length:%d", dataLen); // temporary + Dbprintf("RxEmpty ERROR, data length:%d", dataLen); // temporary } // secondary buffer sets as primary, secondary buffer was stopped if (!AT91C_BASE_PDC_SSC->PDC_RNCR) { @@ -3121,10 +3064,7 @@ void RAMFUNC SniffMifare(uint8_t param) { if (MfSniffLogic(receivedCmd, Uart.len, Uart.parity, Uart.bitCount, TRUE)) break; - /* And ready to receive another command. */ UartInit(receivedCmd, receivedCmdPar); - - /* And also reset the demod code */ DemodReset(); } ReaderIsActive = (Uart.state != STATE_UNSYNCD); @@ -3138,10 +3078,7 @@ void RAMFUNC SniffMifare(uint8_t param) { if (MfSniffLogic(receivedResponse, Demod.len, Demod.parity, Demod.bitCount, FALSE)) break; - // 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); @@ -3159,7 +3096,8 @@ void RAMFUNC SniffMifare(uint8_t param) { FpgaDisableSscDma(); MfSniffEnd(); - LEDsoff(); Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.len=%x", maxDataLen, Uart.state, Uart.len); + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); set_tracing(FALSE); } -- 2.39.2