proxmark3/client/mfkey.c
2017-07-27 20:48:49 +02:00

96 lines
3 KiB
C

//-----------------------------------------------------------------------------
// Merlok - June 2011
// Roel - Dec 2009
// Unknown author
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// MIFARE Darkside hack
//-----------------------------------------------------------------------------
#include "mfkey.h"
#include "crapto1/crapto1.h"
// recover key from 2 different reader responses on same tag challenge
bool mfkey32(nonces_t data, uint64_t *outputkey) {
struct Crypto1State *s,*t;
uint64_t outkey = 0;
uint64_t key = 0; // recovered key
bool isSuccess = false;
uint8_t counter = 0;
s = lfsr_recovery32(data.ar ^ prng_successor(data.nonce, 64), 0);
for(t = s; t->odd | t->even; ++t) {
lfsr_rollback_word(t, 0, 0);
lfsr_rollback_word(t, data.nr, 1);
lfsr_rollback_word(t, data.cuid ^ data.nonce, 0);
crypto1_get_lfsr(t, &key);
crypto1_word(t, data.cuid ^ data.nonce, 0);
crypto1_word(t, data.nr2, 1);
if (data.ar2 == (crypto1_word(t, 0, 0) ^ prng_successor(data.nonce, 64))) {
outkey = key;
counter++;
if (counter == 20) break;
}
}
isSuccess = (counter == 1);
*outputkey = ( isSuccess ) ? outkey : 0;
crypto1_destroy(s);
return isSuccess;
}
// recover key from 2 reader responses on 2 different tag challenges
bool mfkey32_moebius(nonces_t data, uint64_t *outputkey) {
struct Crypto1State *s, *t;
uint64_t outkey = 0;
uint64_t key = 0; // recovered key
bool isSuccess = false;
int counter = 0;
s = lfsr_recovery32(data.ar ^ prng_successor(data.nonce, 64), 0);
for(t = s; t->odd | t->even; ++t) {
lfsr_rollback_word(t, 0, 0);
lfsr_rollback_word(t, data.nr, 1);
lfsr_rollback_word(t, data.cuid ^ data.nonce, 0);
crypto1_get_lfsr(t, &key);
crypto1_word(t, data.cuid ^ data.nonce2, 0);
crypto1_word(t, data.nr2, 1);
if (data.ar2 == (crypto1_word(t, 0, 0) ^ prng_successor(data.nonce2, 64))) {
outkey=key;
++counter;
if (counter==20)
break;
}
}
isSuccess = (counter == 1);
*outputkey = ( isSuccess ) ? outkey : 0;
crypto1_destroy(s);
return isSuccess;
}
// recover key from reader response and tag response of one authentication sequence
int mfkey64(nonces_t data, uint64_t *outputkey){
uint64_t key = 0; // recovered key
uint32_t ks2; // keystream used to encrypt reader response
uint32_t ks3; // keystream used to encrypt tag response
struct Crypto1State *revstate;
// Extract the keystream from the messages
ks2 = data.ar ^ prng_successor(data.nonce, 64);
ks3 = data.at ^ prng_successor(data.nonce, 96);
revstate = lfsr_recovery64(ks2, ks3);
lfsr_rollback_word(revstate, 0, 0);
lfsr_rollback_word(revstate, 0, 0);
lfsr_rollback_word(revstate, data.nr, 1);
lfsr_rollback_word(revstate, data.cuid ^ data.nonce, 0);
crypto1_get_lfsr(revstate, &key);
crypto1_destroy(revstate);
*outputkey = key;
return 0;
}