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Experimeting with finding the "WDT_HIT" bug in "Hf mf mifare", which not shows if "hf mf dbg" is set to 3 or more...

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This commit is contained in:
iceman1001 2016-01-25 20:21:11 +01:00
parent 5f5254d631
commit 4c0cf2d215
1 changed files with 154 additions and 131 deletions
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285
armsrc/iso14443a.c
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@ -106,8 +106,6 @@ static uint32_t NextTransferTime;
static uint32_t LastTimeProxToAirStart;
static uint32_t LastProxToAirDuration;
// CARD TO READER - manchester
// Sequence D: 11110000 modulation with subcarrier during first half
// Sequence E: 00001111 modulation with subcarrier during second half
@ -127,13 +125,11 @@ void iso14a_set_trigger(bool enable) {
trigger = enable;
}
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);
}
void iso14a_set_ATS_timeout(uint8_t *ats) {
uint8_t tb1;
@ -142,20 +138,22 @@ void iso14a_set_ATS_timeout(uint8_t *ats) {
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)
if ((ats[1] & 0x10) == 0x10) // there is an interface byte TA(1) preceding TB(1)
tb1 = ats[3];
} else {
else
tb1 = ats[2];
}
fwi = (tb1 & 0xf0) >> 4; // frame waiting indicator (FWI)
fwt = 256 * 16 * (1 << fwi); // frame waiting time (FWT) in 1/fc
//fwt = 256 * 16 * (1 << fwi); // frame waiting time (FWT) in 1/fc
fwt = 4096 * (1 << fwi);
iso14a_set_timeout(fwt/(8*16));
//iso14a_set_timeout(fwt/(8*16));
iso14a_set_timeout(fwt/128);
}
}
}
//-----------------------------------------------------------------------------
// Generate the parity value for a byte sequence
//
@ -1059,10 +1057,12 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data)
{ .response = response3a, .response_n = sizeof(response3a) }, // Acknowledge select - cascade 2
{ .response = response5, .response_n = sizeof(response5) }, // Authentication answer (random nonce)
{ .response = response6, .response_n = sizeof(response6) }, // dummy ATS (pseudo-ATR), answer to RATS
//{ .response = response7_NTAG, .response_n = sizeof(response7_NTAG)}, // EV1/NTAG GET_VERSION response
{ .response = response8, .response_n = sizeof(response8) } // EV1/NTAG PACK response
};
//{ .response = response7_NTAG, .response_n = sizeof(response7_NTAG)}, // EV1/NTAG GET_VERSION response
//{ .response = response9, .response_n = sizeof(response9) } // EV1/NTAG CHK_TEAR response
};
// Allocate 512 bytes for the dynamic modulation, created when the reader queries for it
// Such a response is less time critical, so we can prepare them on the fly
@ -1112,6 +1112,9 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data)
LED_A_ON();
for(;;) {
WDT_HIT();
// Clean receive command buffer
if(!GetIso14443aCommandFromReader(receivedCmd, receivedCmdPar, &len)) {
DbpString("Button press");
@ -1434,7 +1437,7 @@ void PrepareDelayedTransfer(uint16_t delay)
for (uint16_t i = 0; i < delay; i++) {
bitmask |= (0x01 << i);
}
ToSend[ToSendMax++] = 0x00;
ToSend[++ToSendMax] = 0x00;
for (uint16_t i = 0; i < ToSendMax; i++) {
bits_to_shift = ToSend[i] & bitmask;
ToSend[i] = ToSend[i] >> delay;
@ -1466,6 +1469,7 @@ static void TransmitFor14443a(const uint8_t *cmd, uint16_t len, uint32_t *timing
PrepareDelayedTransfer(*timing & 0x00000007); // Delay transfer (fine tuning - up to 7 MF clock ticks)
}
if(MF_DBGLEVEL >= 4 && GetCountSspClk() >= (*timing & 0xfffffff8)) Dbprintf("TransmitFor14443a: Missed timing");
while(GetCountSspClk() < (*timing & 0xfffffff8)); // Delay transfer (multiple of 8 MF clock ticks)
LastTimeProxToAirStart = *timing;
} else {
@ -1481,7 +1485,7 @@ static void TransmitFor14443a(const uint8_t *cmd, uint16_t len, uint32_t *timing
for(;;) {
if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
AT91C_BASE_SSC->SSC_THR = cmd[c];
c++;
++c;
if(c >= len)
break;
}
@ -1886,10 +1890,10 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
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
uint8_t resp[MAX_FRAME_SIZE]; // theoretically. A usual RATS will be much smaller
uint8_t resp_par[MAX_PARITY_SIZE];
byte_t uid_resp[4];
size_t uid_resp_len;
uint8_t resp[MAX_FRAME_SIZE] = {0}; // theoretically. A usual RATS will be much smaller
uint8_t resp_par[MAX_PARITY_SIZE] = {0};
byte_t uid_resp[4] = {0};
size_t uid_resp_len = 0;
uint8_t sak = 0x04; // cascade uid
int cascade_level = 0;
@ -1908,16 +1912,13 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
}
if (anticollision) {
// clear uid
if (uid_ptr) {
memset(uid_ptr,0,10);
}
// clear uid
if (uid_ptr)
memset(uid_ptr,0,10);
}
// check for proprietary anticollision:
if ((resp[0] & 0x1F) == 0) {
return 3;
}
if ((resp[0] & 0x1F) == 0) return 3;
// OK we will select at least at cascade 1, lets see if first byte of UID was 0x88 in
// which case we need to make a cascade 2 request and select - this is a long UID
@ -1928,40 +1929,41 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
if (anticollision) {
// SELECT_ALL
ReaderTransmit(sel_all, sizeof(sel_all), NULL);
if (!ReaderReceive(resp, resp_par)) return 0;
ReaderTransmit(sel_all, sizeof(sel_all), NULL);
if (!ReaderReceive(resp, resp_par)) return 0;
if (Demod.collisionPos) { // we had a collision and need to construct the UID bit by bit
memset(uid_resp, 0, 4);
uint16_t uid_resp_bits = 0;
uint16_t collision_answer_offset = 0;
// anti-collision-loop:
while (Demod.collisionPos) {
Dbprintf("Multiple tags detected. Collision after Bit %d", Demod.collisionPos);
for (uint16_t i = collision_answer_offset; i < Demod.collisionPos; i++, uid_resp_bits++) { // add valid UID bits before collision point
uint16_t UIDbit = (resp[i/8] >> (i % 8)) & 0x01;
uid_resp[uid_resp_bits / 8] |= UIDbit << (uid_resp_bits % 8);
if (Demod.collisionPos) { // we had a collision and need to construct the UID bit by bit
memset(uid_resp, 0, 4);
uint16_t uid_resp_bits = 0;
uint16_t collision_answer_offset = 0;
// anti-collision-loop:
while (Demod.collisionPos) {
Dbprintf("Multiple tags detected. Collision after Bit %d", Demod.collisionPos);
for (uint16_t i = collision_answer_offset; i < Demod.collisionPos; i++, uid_resp_bits++) { // add valid UID bits before collision point
uint16_t UIDbit = (resp[i/8] >> (i % 8)) & 0x01;
uid_resp[uid_resp_bits / 8] |= UIDbit << (uid_resp_bits % 8);
}
uid_resp[uid_resp_bits/8] |= 1 << (uid_resp_bits % 8); // next time select the card(s) with a 1 in the collision position
uid_resp_bits++;
// construct anticollosion command:
sel_uid[1] = ((2 + uid_resp_bits/8) << 4) | (uid_resp_bits & 0x07); // length of data in bytes and bits
for (uint16_t i = 0; i <= uid_resp_bits/8; i++) {
sel_uid[2+i] = uid_resp[i];
}
collision_answer_offset = uid_resp_bits%8;
ReaderTransmitBits(sel_uid, 16 + uid_resp_bits, NULL);
if (!ReaderReceiveOffset(resp, collision_answer_offset, resp_par)) return 0;
}
uid_resp[uid_resp_bits/8] |= 1 << (uid_resp_bits % 8); // next time select the card(s) with a 1 in the collision position
uid_resp_bits++;
// construct anticollosion command:
sel_uid[1] = ((2 + uid_resp_bits/8) << 4) | (uid_resp_bits & 0x07); // length of data in bytes and bits
for (uint16_t i = 0; i <= uid_resp_bits/8; i++) {
sel_uid[2+i] = uid_resp[i];
// finally, add the last bits and BCC of the UID
for (uint16_t i = collision_answer_offset; i < (Demod.len-1)*8; i++, uid_resp_bits++) {
uint16_t UIDbit = (resp[i/8] >> (i%8)) & 0x01;
uid_resp[uid_resp_bits/8] |= UIDbit << (uid_resp_bits % 8);
}
collision_answer_offset = uid_resp_bits%8;
ReaderTransmitBits(sel_uid, 16 + uid_resp_bits, NULL);
if (!ReaderReceiveOffset(resp, collision_answer_offset, resp_par)) return 0;
}
// finally, add the last bits and BCC of the UID
for (uint16_t i = collision_answer_offset; i < (Demod.len-1)*8; i++, uid_resp_bits++) {
uint16_t UIDbit = (resp[i/8] >> (i%8)) & 0x01;
uid_resp[uid_resp_bits/8] |= UIDbit << (uid_resp_bits % 8);
}
} else { // no collision, use the response to SELECT_ALL as current uid
memcpy(uid_resp, resp, 4);
}
} else { // no collision, use the response to SELECT_ALL as current uid
memcpy(uid_resp, resp, 4);
}
} else {
if (cascade_level < num_cascades - 1) {
uid_resp[0] = 0x88;
@ -1973,9 +1975,8 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
uid_resp_len = 4;
// calculate crypto UID. Always use last 4 Bytes.
if(cuid_ptr) {
if(cuid_ptr)
*cuid_ptr = bytes_to_num(uid_resp, 4);
}
// Construct SELECT UID command
sel_uid[1] = 0x70; // transmitting a full UID (1 Byte cmd, 1 Byte NVB, 4 Byte UID, 1 Byte BCC, 2 Bytes CRC)
@ -1986,6 +1987,7 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
// Receive the SAK
if (!ReaderReceive(resp, resp_par)) return 0;
sak = resp[0];
// Test if more parts of the uid are coming
@ -1998,9 +2000,8 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
uid_resp_len = 3;
}
if(uid_ptr && anticollision) {
if(uid_ptr && anticollision)
memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
}
if(p_hi14a_card) {
memcpy(p_hi14a_card->uid + (cascade_level*3), uid_resp, uid_resp_len);
@ -2021,7 +2022,6 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
ReaderTransmit(rats, sizeof(rats), NULL);
if (!(len = ReaderReceive(resp, resp_par))) return 0;
if(p_hi14a_card) {
memcpy(p_hi14a_card->ats, resp, sizeof(p_hi14a_card->ats));
@ -2219,7 +2219,7 @@ void ReaderMifare(bool first_try, uint8_t block )
//uint8_t mf_auth[] = { 0x60,0x05, 0x58, 0x2c };
uint8_t mf_auth[] = { 0x60,0x00, 0x00, 0x00 };
uint8_t mf_nr_ar[] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
static uint8_t mf_nr_ar3;
static uint8_t mf_nr_ar3 = 0;
mf_auth[1] = block;
AppendCrc14443a(mf_auth, 2);
@ -2227,14 +2227,6 @@ void ReaderMifare(bool first_try, uint8_t block )
uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE] = {0x00};
uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE] = {0x00};
if (first_try)
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 par[1] = {0}; // maximum 8 Bytes to be sent here, 1 byte parity is therefore enough
static byte_t par_low = 0;
@ -2248,49 +2240,62 @@ void ReaderMifare(bool first_try, uint8_t block )
byte_t par_list[8] = {0x00};
byte_t ks_list[8] = {0x00};
#define PRNG_SEQUENCE_LENGTH (1 << 16);
static uint32_t sync_time = 0;
static int32_t sync_cycles = 0;
int catch_up_cycles = 0;
int last_catch_up = 0;
uint16_t elapsed_prng_sequences = 0;
uint16_t elapsed_prng_sequences = 1;
uint16_t consecutive_resyncs = 0;
int isOK = 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 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+1][NUM_DEBUG_INFOS];
uint32_t select_time = 0;
uint32_t halt_time = 0;
//uint8_t caller[7] = {0};
// init to zero.
for (uint16_t i = 0; i < MAX_STRATEGY+1; ++i)
for(uint16_t j = 0; j < NUM_DEBUG_INFOS; ++j)
debug_info[i][j] = 0;
LED_A_ON();
LED_B_OFF();
LED_C_OFF();
if (first_try)
iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
// free eventually allocated BigBuf memory. We want all for tracing.
BigBuf_free();
clear_trace();
set_tracing(TRUE);
if (first_try) {
mf_nr_ar3 = 0;
sync_time = GetCountSspClk() & 0xfffffff8;
sync_cycles = PRNG_SEQUENCE_LENGTH; //65536; //0x10000 // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).
mf_nr_ar3 = 0;
nt_attacked = 0;
par[0] = 0;
}
else {
} else {
// we were unsuccessful on a previous call. Try another READER nonce (first 3 parity bits remain the same)
mf_nr_ar3++;
mf_nr_ar[3] = mf_nr_ar3;
par[0] = par_low;
}
LED_A_ON();
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 = 0;
uint32_t halt_time = 0;
for(uint16_t i = 0; TRUE; ++i) {
LED_C_ON();
LED_C_ON();
for(uint16_t i = 0; TRUE; ++i) {
WDT_HIT();
// Test if the action was cancelled
@ -2300,12 +2305,12 @@ void ReaderMifare(bool first_try, uint8_t block )
}
if (strategy == 2) {
// test with additional hlt command
// 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 hlt command (additional debugging).", len);
}
if (len && MF_DBGLEVEL >= 3)
Dbprintf("Unexpected response of %d bytes to halt command (additional debugging).\n", len);
}
if (strategy == 3) {
@ -2314,28 +2319,35 @@ void ReaderMifare(bool first_try, uint8_t block )
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 >= 1) Dbprintf("Mifare: Can't select card");
if (!iso14443a_select_card(uid, NULL, &cuid, true, 0)) {
if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Can't select card\n");
continue;
}
select_time = GetCountSspClk();
select_time = GetCountSspClk() & 0xfffffff8;
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
WDT_HIT();
while(GetCountSspClk() > sync_time) {
elapsed_prng_sequences++;
++elapsed_prng_sequences;
sync_time = (sync_time & 0xfffffff8) + sync_cycles;
}
//sync_time += sync_cycles;
//sync_time &= 0xfffffff8;
}
WDT_HIT();
// Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked)
ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
if (MF_DBGLEVEL == 2) Dbprintf("sync_time %d \n", sync_time);
} else {
// collect some information on tag nonces for debugging:
@ -2357,10 +2369,8 @@ void ReaderMifare(bool first_try, uint8_t block )
}
// Receive the (4 Byte) "random" nonce
if (!ReaderReceive(receivedAnswer, receivedAnswerPar)) {
if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Couldn't receive tag nonce");
if (!ReaderReceive(receivedAnswer, receivedAnswerPar))
continue;
}
previous_nt = nt;
nt = bytes_to_num(receivedAnswer, 4);
@ -2382,6 +2392,7 @@ void ReaderMifare(bool first_try, uint8_t block )
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
@ -2389,44 +2400,53 @@ void ReaderMifare(bool first_try, uint8_t block )
} else { // continue for a while, just to collect some debug info
++debug_info_nr;
debug_info[strategy][debug_info_nr] = nt_distance;
if (debug_info_nr == NUM_DEBUG_INFOS) {
if (debug_info_nr == NUM_DEBUG_INFOS-1) {
++strategy;
debug_info_nr = 0;
}
continue;
}
}
sync_cycles = (sync_cycles - nt_distance/elapsed_prng_sequences);
if (sync_cycles <= 0) {
if (sync_cycles <= 0)
sync_cycles += PRNG_SEQUENCE_LENGTH;
}
if (MF_DBGLEVEL >= 3) {
if (MF_DBGLEVEL >= 2)
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);
}
continue;
}
}
if ((nt != nt_attacked) && nt_attacked) { // we somehow lost sync. Try to catch up again...
catch_up_cycles = -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;
if (catch_up_cycles == last_catch_up) {
++consecutive_resyncs;
}
else {
} else {
last_catch_up = catch_up_cycles;
consecutive_resyncs = 0;
}
sync_cycles += catch_up_cycles;
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);
}
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);
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);
} 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);
last_catch_up = 0;
catch_up_cycles = 0;
consecutive_resyncs = 0;
@ -2474,15 +2494,20 @@ void ReaderMifare(bool first_try, uint8_t block )
mf_nr_ar[3] &= 0x1F;
WDT_HIT();
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]);
}
}
}
for (uint16_t i = 0; i < MAX_STRATEGY+1; ++i)
for(uint16_t j = 0; j < NUM_DEBUG_INFOS; ++j)
Dbprintf("info[%d][%d] = %d", i, j, debug_info[i][j]);
}
// reset sync_time.
if ( isOK == 1) {
sync_time = 0;
sync_cycles = 0;
mf_nr_ar3 = 0;
nt_attacked = 0;
par[0] = 0;
}
byte_t buf[28] = {0x00};
@ -2494,10 +2519,8 @@ void ReaderMifare(bool first_try, uint8_t block )
cmd_send(CMD_ACK,isOK,0,0,buf,28);
// Thats it...
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
LEDsoff();
set_tracing(FALSE);
}