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chg: 'hf mf nack' - extracted in into mifarehost for easier usage in other cmds like

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'hf 14a info'
chg: 'hf mf nack' - changes on devices side from @doegox   Thanks!
This commit is contained in:
iceman1001 2017-12-05 23:34:52 +01:00
commit 0a1a48df01
5 changed files with 88 additions and 50 deletions
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18
armsrc/iso14443a.c
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@ -2552,6 +2552,7 @@ void ReaderMifare(bool first_try, uint8_t block, uint8_t keytype ) {
/*
* Mifare Classic NACK-bug detection
* Thanks to @doegox for the feedback and new approaches.
*/
void DetectNACKbug() {
@ -2571,6 +2572,7 @@ void DetectNACKbug() {
uint16_t sync_tries = 0;
uint32_t sync_time = 0;
bool have_uid = false;
bool received_nack;
// Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).
uint32_t sync_cycles = PRNG_SEQUENCE_LENGTH;
@ -2592,6 +2594,18 @@ void DetectNACKbug() {
uint16_t i;
for (i = 0; true; ++i) {
received_nack = false;
if ((i==10) && (num_nacks == i)) {
// Cards always leaks a NACK, no matter the parity
isOK = 2;
break;
}
if ( (i > 1) && (num_nacks == 1) ) {
// NACK bug
isOK = 1;
break;
}
WDT_HIT();
// Test if the action was cancelled
@ -2639,7 +2653,7 @@ void DetectNACKbug() {
// Receive the (4 Byte) "random" nonce from TAG
if (!ReaderReceive(receivedAnswer, receivedAnswerPar))
continue;
previous_nt = nt;
nt = bytes_to_num(receivedAnswer, 4);
@ -2735,7 +2749,7 @@ void DetectNACKbug() {
// Receive answer. This will be a 4 Bit NACK when the 8 parity bits are OK after decoding
if (ReaderReceive(receivedAnswer, receivedAnswerPar)) {
catch_up_cycles = 8; // the PRNG is delayed by 8 cycles due to the NAC (4Bits = 0x05 encrypted) transfer
isOK = 1;
received_nack = true;
num_nacks++;
}