git.zerfleddert.de Git - proxmark3-svn/blob - tools/nonce2key/nonce2key.c

   1 #include "crapto1.h"
   2 #define __STDC_FORMAT_MACROS
   3 #include <inttypes.h>
   4 #include <stdio.h>
   5 #include <time.h>
   6 typedef unsigned char byte_t;
   7
   8 int main(const int argc, const char* argv[]) {
   9         struct Crypto1State *state;
  10         uint32_t pos, uid, nt, nr, rr, nr_diff, ks1, ks2;
  11         byte_t bt, i, ks3x[8], par[8][8];
  12         uint64_t key, key_recovered;
  13         uint64_t par_info;
  14         uint64_t ks_info;
  15         nr = rr = 0;
  16
  17         if (argc < 5) {
  18                 printf("\nsyntax: %s <uid> <nt> <par> <ks>\n\n",argv[0]);
  19                 return 1;
  20         }
  21         sscanf(argv[1],"%08x", &uid);
  22         sscanf(argv[2],"%08x", &nt);
  23         sscanf(argv[3],"%016" SCNx64 ,&par_info);
  24         sscanf(argv[4],"%016" SCNx64 ,&ks_info);
  25
  26         // Reset the last three significant bits of the reader nonce
  27         nr &= 0xffffff1f;
  28
  29         printf("\nuid(%08x) nt(%08x) par(%016" PRIx64 ") ks(%016" PRIx64 ")\n\n", uid, nt, par_info, ks_info);
  30
  31         for ( pos = 0; pos < 8; pos++ ) {
  32                 ks3x[7-pos] = (ks_info >> (pos*8)) & 0x0f;
  33                 bt = (par_info >> (pos*8)) & 0xff;
  34
  35                 for ( i = 0; i < 8; i++) {
  36                         par[7-pos][i] = (bt >> i) & 0x01;
  37                 }
  38         }
  39
  40         printf("|diff|{nr}    |ks3|ks3^5|parity         |\n");
  41         printf("+----+--------+---+-----+---------------+\n");
  42
  43         for ( i = 0; i < 8; i++) {
  44                 nr_diff = nr | i << 5;
  45                 printf("| %02x |%08x| %01x |  %01x  |", i << 5, nr_diff, ks3x[i], ks3x[i]^5);
  46
  47                 for ( pos = 0; pos < 7; pos++)
  48                         printf("%01x,", par[i][pos]);
  49                 printf("%01x|\n", par[i][7]);
  50         }
  51         printf("+----+--------+---+-----+---------------+\n");
  52
  53         clock_t t1 = clock();
  54
  55         state = lfsr_common_prefix(nr,rr,ks3x,par);
  56         lfsr_rollback_word(state,uid^nt,0);
  57         crypto1_get_lfsr(state,&key_recovered);
  58         printf("\nkey recovered: %012" PRIx64 "\n\n", key_recovered);
  59         crypto1_destroy(state);
  60
  61         t1 = clock() - t1;
  62         if ( t1 > 0 ) printf("Time in nonce2key: %.0f ticks \n", (float)t1);
  63         return 0;
  64 }