proxmark3/tools/mfkey/mfkey32.c
2015-05-13 09:18:37 +02:00

71 lines
2.1 KiB
C
Executable file

#define __STDC_FORMAT_MACROS
#include <inttypes.h>
#define llx PRIx64
#define lli PRIi64
// Test-file: test2.c
#include "crapto1.h"
#include <stdio.h>
#include <stdlib.h>
int main (int argc, char *argv[]) {
struct Crypto1State *s,*t;
uint64_t key; // recovered key
uint32_t uid; // serial number
uint32_t nt; // tag challenge
uint32_t nr0_enc; // first encrypted reader challenge
uint32_t ar0_enc; // first encrypted reader response
uint32_t nr1_enc; // second encrypted reader challenge
uint32_t ar1_enc; // second encrypted reader response
uint32_t ks2; // keystream used to encrypt reader response
printf("MIFARE Classic key recovery - based 32 bits of keystream\n");
printf("Recover key from two 32-bit reader authentication answers only!\n\n");
if (argc < 7) {
printf(" syntax: %s <uid> <nt> <{nr_0}> <{ar_0}> <{nr_1}> <{ar_1}>\n\n",argv[0]);
return 1;
}
sscanf(argv[1],"%x",&uid);
sscanf(argv[2],"%x",&nt);
sscanf(argv[3],"%x",&nr0_enc);
sscanf(argv[4],"%x",&ar0_enc);
sscanf(argv[5],"%x",&nr1_enc);
sscanf(argv[6],"%x",&ar1_enc);
printf("Recovering key for:\n");
printf(" uid: %08x\n",uid);
printf(" nt: %08x\n",nt);
printf(" {nr_0}: %08x\n",nr0_enc);
printf(" {ar_0}: %08x\n",ar0_enc);
printf(" {nr_1}: %08x\n",nr1_enc);
printf(" {ar_1}: %08x\n",ar1_enc);
// Generate lfsr succesors of the tag challenge
printf("\nLFSR succesors of the tag challenge:\n");
printf(" nt': %08x\n",prng_successor(nt, 64));
printf(" nt'': %08x\n",prng_successor(nt, 96));
// Extract the keystream from the messages
printf("\nKeystream used to generate {ar} and {at}:\n");
ks2 = ar0_enc ^ prng_successor(nt, 64);
printf(" ks2: %08x\n",ks2);
s = lfsr_recovery32(ar0_enc ^ prng_successor(nt, 64), 0);
for(t = s; t->odd | t->even; ++t) {
lfsr_rollback_word(t, 0, 0);
lfsr_rollback_word(t, nr0_enc, 1);
lfsr_rollback_word(t, uid ^ nt, 0);
crypto1_get_lfsr(t, &key);
crypto1_word(t, uid ^ nt, 0);
crypto1_word(t, nr1_enc, 1);
if (ar1_enc == (crypto1_word(t, 0, 0) ^ prng_successor(nt, 64))) {
printf("\nFound Key: [%012"llx"]\n\n",key);
break;}
}
free(s);
return 0;
}