} tUart;
static uint32_t iso14a_timeout;
+#define MAX_ISO14A_TIMEOUT 524288
+
int rsamples = 0;
uint8_t trigger = 0;
// the block number for the ISO14443-4 PCB
void iso14a_set_timeout(uint32_t timeout) {
- iso14a_timeout = timeout;
- if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443A Timeout set to %ld (%dms)", iso14a_timeout, iso14a_timeout / 106);
+ // adjust timeout by FPGA delays and 2 additional ssp_frames to detect SOF
+ iso14a_timeout = timeout + (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/(16*8) + 2;
+ if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443A Timeout set to %ld (%dms)", timeout, timeout / 106);
}
-static void iso14a_set_ATS_timeout(uint8_t *ats) {
-
- uint8_t tb1;
- uint8_t fwi;
- uint32_t fwt;
-
- if (ats[0] > 1) { // there is a format byte T0
- if ((ats[1] & 0x20) == 0x20) { // there is an interface byte TB(1)
- if ((ats[1] & 0x10) == 0x10) { // there is an interface byte TA(1) preceding TB(1)
- tb1 = ats[3];
- } else {
- tb1 = ats[2];
- }
- fwi = (tb1 & 0xf0) >> 4; // frame waiting indicator (FWI)
- fwt = 256 * 16 * (1 << fwi); // frame waiting time (FWT) in 1/fc
-
- iso14a_set_timeout(fwt/(8*16));
- }
- }
+uint32_t iso14a_get_timeout(void) {
+ return iso14a_timeout - (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/(16*8) - 2;
}
-
//-----------------------------------------------------------------------------
// Generate the parity value for a byte sequence
//
// Transmit the command (to the tag) that was placed in ToSend[].
// Parameter timing:
// if NULL: transfer at next possible time, taking into account
-// request guard time and frame delay time
+// request guard time, startup frame guard time and frame delay time
// if == 0: transfer immediately and return time of transfer
// if != 0: delay transfer until time specified
//-------------------------------------------------------------------------------------
return Demod.len;
}
+
+static void iso14a_set_ATS_times(uint8_t *ats) {
+
+ uint8_t tb1;
+ uint8_t fwi, sfgi;
+ uint32_t fwt, sfgt;
+
+ if (ats[0] > 1) { // there is a format byte T0
+ if ((ats[1] & 0x20) == 0x20) { // there is an interface byte TB(1)
+ if ((ats[1] & 0x10) == 0x10) { // there is an interface byte TA(1) preceding TB(1)
+ tb1 = ats[3];
+ } else {
+ tb1 = ats[2];
+ }
+ fwi = (tb1 & 0xf0) >> 4; // frame waiting time integer (FWI)
+ if (fwi != 15) {
+ fwt = 256 * 16 * (1 << fwi); // frame waiting time (FWT) in 1/fc
+ iso14a_set_timeout(fwt/(8*16));
+ }
+ sfgi = tb1 & 0x0f; // startup frame guard time integer (SFGI)
+ if (sfgi != 0 && sfgi != 15) {
+ sfgt = 256 * 16 * (1 << sfgi); // startup frame guard time (SFGT) in 1/fc
+ NextTransferTime = MAX(NextTransferTime, Demod.endTime + (sfgt - DELAY_AIR2ARM_AS_READER - DELAY_ARM2AIR_AS_READER)/16);
+ }
+ }
+ }
+}
+
+
+static int GetATQA(uint8_t *resp, uint8_t *resp_par) {
+
+#define WUPA_RETRY_TIMEOUT 10 // 10ms
+ uint8_t wupa[] = { 0x52 }; // 0x26 - REQA 0x52 - WAKE-UP
+
+ uint32_t save_iso14a_timeout = iso14a_get_timeout();
+ iso14a_set_timeout(1236/(16*8)+1); // response to WUPA is expected at exactly 1236/fc. No need to wait longer.
+
+ uint32_t start_time = GetTickCount();
+ int len;
+
+ // we may need several tries if we did send an unknown command or a wrong authentication before...
+ do {
+ // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
+ ReaderTransmitBitsPar(wupa, 7, NULL, NULL);
+ // Receive the ATQA
+ len = ReaderReceive(resp, resp_par);
+ } while (len == 0 && GetTickCount() <= start_time + WUPA_RETRY_TIMEOUT);
+
+ iso14a_set_timeout(save_iso14a_timeout);
+ return len;
+}
+
+
// performs iso14443a anticollision (optional) and card select procedure
// fills the uid and cuid pointer unless NULL
// fills the card info record unless NULL
// and num_cascades must be set (1: 4 Byte UID, 2: 7 Byte UID, 3: 10 Byte UID)
// requests ATS unless no_rats is true
int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, uint32_t *cuid_ptr, bool anticollision, uint8_t num_cascades, bool no_rats) {
- uint8_t wupa[] = { 0x52 }; // 0x26 - REQA 0x52 - WAKE-UP
uint8_t sel_all[] = { 0x93,0x20 };
uint8_t sel_uid[] = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
uint8_t rats[] = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0
p_hi14a_card->ats_len = 0;
}
- // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
- ReaderTransmitBitsPar(wupa, 7, NULL, NULL);
-
- // Receive the ATQA
- if(!ReaderReceive(resp, resp_par)) return 0;
+ if (!GetATQA(resp, resp_par)) {
+ return 0;
+ }
if(p_hi14a_card) {
memcpy(p_hi14a_card->atqa, resp, 2);
// reset the PCB block number
iso14_pcb_blocknum = 0;
- // set default timeout based on ATS
- iso14a_set_ATS_timeout(resp);
+ // set default timeout and delay next transfer based on ATS
+ iso14a_set_ATS_times(resp);
+
}
return 1;
}
} else{
// S-Block WTX
while((data_bytes[0] & 0xF2) == 0xF2) {
+ uint32_t save_iso14a_timeout = iso14a_get_timeout();
+ // temporarily increase timeout
+ iso14a_set_timeout(MAX((data_bytes[1] & 0x3f) * save_iso14a_timeout, MAX_ISO14A_TIMEOUT));
// Transmit WTX back
// byte1 - WTXM [1..59]. command FWT=FWT*WTXM
data_bytes[1] = data_bytes[1] & 0x3f; // 2 high bits mandatory set to 0b
AppendCrc14443a(data_bytes, len - 2);
// transmit S-Block
ReaderTransmit(data_bytes, len, NULL);
- // retrieve the result again
+ // retrieve the result again (with increased timeout)
len = ReaderReceive(data, parity);
data_bytes = data;
+ // restore timeout
+ iso14a_set_timeout(save_iso14a_timeout);
}
// if we received an I- or R(ACK)-Block with a block number equal to the
uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE];
uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE];
- if (first_try) {
- iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
- }
+ iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
// free eventually allocated BigBuf memory. We want all for tracing.
BigBuf_free();
clear_trace();
set_tracing(true);
- byte_t nt_diff = 0;
+ uint8_t nt_diff = 0;
uint8_t par[1] = {0}; // maximum 8 Bytes to be sent here, 1 byte parity is therefore enough
- static byte_t par_low = 0;
+ static uint8_t par_low = 0;
bool led_on = true;
uint8_t uid[10] ={0};
uint32_t cuid;
uint32_t nt = 0;
uint32_t previous_nt = 0;
static uint32_t nt_attacked = 0;
- byte_t par_list[8] = {0x00};
- byte_t ks_list[8] = {0x00};
+ uint8_t par_list[8] = {0x00};
+ uint8_t ks_list[8] = {0x00};
#define PRNG_SEQUENCE_LENGTH (1 << 16);
- static uint32_t sync_time;
+ uint32_t sync_time = GetCountSspClk() & 0xfffffff8;
static int32_t sync_cycles;
int catch_up_cycles = 0;
int last_catch_up = 0;
if (first_try) {
mf_nr_ar3 = 0;
- sync_time = GetCountSspClk() & 0xfffffff8;
+ par[0] = par_low = 0;
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;
- par[0] = 0;
}
else {
// we were unsuccessful on a previous call. Try another READER nonce (first 3 parity bits remain the same)
#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 SYNC_TIME_BUFFER 16 // if there is only SYNC_TIME_BUFFER left before next planned sync, wait for next PRNG cycle
#define NUM_DEBUG_INFOS 8 // per strategy
#define MAX_STRATEGY 3
uint16_t unexpected_random = 0;
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) {
+ // if we missed the sync time already or are about to miss it, advance to the next nonce repeat
+ while(sync_time < GetCountSspClk() + SYNC_TIME_BUFFER) {
elapsed_prng_sequences++;
sync_time = (sync_time & 0xfffffff8) + sync_cycles;
}
}
}
- byte_t buf[28];
+ uint8_t buf[32];
memcpy(buf + 0, uid, 4);
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);
+ memcpy(buf + 24, mf_nr_ar, 8);
- cmd_send(CMD_ACK, isOK, 0, 0, buf, 28);
+ cmd_send(CMD_ACK, isOK, 0, 0, buf, 32);
// Thats it...
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
for(uint32_t sniffCounter = 0; true; ) {
if(BUTTON_PRESS()) {
- DbpString("cancelled by button");
+ DbpString("Canceled by button.");
break;
}
if(!TagIsActive) { // no need to try decoding tag data if the reader is sending
uint8_t readerdata = (previous_data & 0xF0) | (*data >> 4);
if(MillerDecoding(readerdata, (sniffCounter-1)*4)) {
- LED_C_INV();
+ LED_B_ON();
+ LED_C_OFF();
+
if (MfSniffLogic(receivedCmd, Uart.len, Uart.parity, Uart.bitCount, true)) break;
/* And ready to receive another command. */
if(!ReaderIsActive) { // no need to try decoding tag data if the reader is sending
uint8_t tagdata = (previous_data << 4) | (*data & 0x0F);
if(ManchesterDecoding(tagdata, 0, (sniffCounter-1)*4)) {
- LED_C_INV();
+ LED_B_OFF();
+ LED_C_ON();
if (MfSniffLogic(receivedResponse, Demod.len, Demod.parity, Demod.bitCount, false)) break;
} // main cycle
- DbpString("COMMAND FINISHED");
+ DbpString("COMMAND FINISHED.");
FpgaDisableSscDma();
MfSniffEnd();