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

   1 //-----------------------------------------------------------------------------
   2 // Merlok - June 2011
   3 // Roel - Dec 2009
   4 // Unknown author
   5 //
   6 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   7 // at your option, any later version. See the LICENSE.txt file for the text of
   8 // the license.
   9 //-----------------------------------------------------------------------------
  10 // MIFARE Darkside hack
  11 //-----------------------------------------------------------------------------
  12
  13 #define __STDC_FORMAT_MACROS
  14 #include <inttypes.h>
  15 #define llx PRIx64
  16
  17 #include "nonce2key.h"
  18 #include "ui.h"
  19
  20 int nonce2key(uint32_t uid, uint32_t nt, uint64_t par_info, uint64_t ks_info, uint64_t * key) {
  21   struct Crypto1State *state, *state_s;
  22   uint32_t pos, nr, rr, nr_diff;//, ks1, ks2;
  23   byte_t bt, i, ks3x[8], par[8][8];
  24   uint64_t key_recovered;
  25   nr = rr = 0;
  26
  27   // Reset the last three significant bits of the reader nonce
  28   nr &= 0xffffff1f;
  29
  30   PrintAndLog("\nuid(%08x) nt(%08x) par(%016"llx") ks(%016"llx")\n\n",uid,nt,par_info,ks_info);
  31
  32   for (pos=0; pos<8; pos++)
  33   {
  34     ks3x[7-pos] = (ks_info >> (pos*8)) & 0x0f;
  35     bt = (par_info >> (pos*8)) & 0xff;
  36     for (i=0; i<8; i++)
  37     {
  38       par[7-pos][i] = (bt >> i) & 0x01;
  39     }
  40   }
  41
  42   printf("|diff|{nr}    |ks3|ks3^5|parity         |\n");
  43   printf("+----+--------+---+-----+---------------+\n");
  44   for (i=0; i<8; i++)
  45   {
  46     nr_diff = nr | i << 5;
  47     printf("| %02x |%08x|",i << 5, nr_diff);
  48     printf(" %01x |  %01x  |",ks3x[i], ks3x[i]^5);
  49     for (pos=0; pos<7; pos++) printf("%01x,", par[i][pos]);
  50     printf("%01x|\n", par[i][7]);
  51   }
  52
  53   state = lfsr_common_prefix(nr, rr, ks3x, par);
  54         state_s = 0;
  55         for (i = 0; (state) && ((state + i)->odd != 0 || (state + i)->even != 0) && (i < 10); i++)
  56         {
  57     printf("%08x|%08x\n",(state+i)->odd, (state+i)->even);
  58                 state_s = state + i;
  59         }
  60   if (!state_s) return 1;
  61
  62   lfsr_rollback_word(state_s, uid^nt, 0);
  63   crypto1_get_lfsr(state_s, &key_recovered);
  64   if (!state) free(state);
  65
  66         *key = key_recovered;
  67
  68   return 0;
  69 }