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 #include "nonce2key.h"
  14 #include "ui.h"
  15
  16 int nonce2key(uint32_t uid, uint32_t nt, uint64_t par_info, uint64_t ks_info, uint64_t * key) {
  17   struct Crypto1State *state, *state_s;
  18   uint32_t pos, nr, rr, nr_diff;//, ks1, ks2;
  19   byte_t bt, i, ks3x[8], par[8][8];
  20   uint64_t key_recovered;
  21   nr = rr = 0;
  22
  23   // Reset the last three significant bits of the reader nonce
  24   nr &= 0xffffff1f;
  25
  26   PrintAndLog("\nuid(%08x) nt(%08x) par(%016llx) ks(%016llx)\n\n",uid,nt,par_info,ks_info);
  27
  28   for (pos=0; pos<8; pos++)
  29   {
  30     ks3x[7-pos] = (ks_info >> (pos*8)) & 0x0f;
  31     bt = (par_info >> (pos*8)) & 0xff;
  32     for (i=0; i<8; i++)
  33     {
  34       par[7-pos][i] = (bt >> i) & 0x01;
  35     }
  36   }
  37
  38   printf("|diff|{nr}    |ks3|ks3^5|parity         |\n");
  39   printf("+----+--------+---+-----+---------------+\n");
  40   for (i=0; i<8; i++)
  41   {
  42     nr_diff = nr | i << 5;
  43     printf("| %02x |%08x|",i << 5, nr_diff);
  44     printf(" %01x |  %01x  |",ks3x[i], ks3x[i]^5);
  45     for (pos=0; pos<7; pos++) printf("%01x,", par[i][pos]);
  46     printf("%01x|\n", par[i][7]);
  47   }
  48
  49   state = lfsr_common_prefix(nr, rr, ks3x, par);
  50         state_s = 0;
  51         for (i = 0; (state) && ((state + i)->odd != 0 || (state + i)->even != 0) && (i < 10); i++)
  52         {
  53     printf("%08x|%08x\n",(state+i)->odd, (state+i)->even);
  54                 state_s = state + i;
  55         }
  56   if (!state_s) return 1;
  57
  58   lfsr_rollback_word(state_s, uid^nt, 0);
  59   crypto1_get_lfsr(state_s, &key_recovered);
  60   if (!state) free(state);
  61
  62         *key = key_recovered;
  63
  64   return 0;
  65 }