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