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

   1 // Merlok, 2011, 2012
   2 // people from mifare@nethemba.com, 2010
   3 //
   4 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   5 // at your option, any later version. See the LICENSE.txt file for the text of
   6 // the license.
   7 //-----------------------------------------------------------------------------
   8 // mifare commands
   9 //-----------------------------------------------------------------------------
  10
  11 #include "mifarehost.h"
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <pthread.h>
  17
  18 #include "crapto1/crapto1.h"
  19 #include "comms.h"
  20 #include "usb_cmd.h"
  21 #include "cmdmain.h"
  22 #include "ui.h"
  23 #include "parity.h"
  24 #include "util.h"
  25 #include "iso14443crc.h"
  26
  27 #include "mifare.h"
  28 #include "mifare4.h"
  29
  30 // mifare tracer flags used in mfTraceDecode()
  31 #define TRACE_IDLE                                              0x00
  32 #define TRACE_AUTH1                                             0x01
  33 #define TRACE_AUTH2                                             0x02
  34 #define TRACE_AUTH_OK                                   0x03
  35 #define TRACE_READ_DATA                                 0x04
  36 #define TRACE_WRITE_OK                                  0x05
  37 #define TRACE_WRITE_DATA                                0x06
  38 #define TRACE_ERROR                                             0xFF
  39
  40
  41 static int compare_uint64(const void *a, const void *b) {
  42         // didn't work: (the result is truncated to 32 bits)
  43         //return (*(int64_t*)b - *(int64_t*)a);
  44
  45         // better:
  46         if (*(uint64_t*)b == *(uint64_t*)a) return 0;
  47         else if (*(uint64_t*)b < *(uint64_t*)a) return 1;
  48         else return -1;
  49 }
  50
  51
  52 // create the intersection (common members) of two sorted lists. Lists are terminated by -1. Result will be in list1. Number of elements is returned.
  53 static uint32_t intersection(uint64_t *list1, uint64_t *list2)
  54 {
  55         if (list1 == NULL || list2 == NULL) {
  56                 return 0;
  57         }
  58         uint64_t *p1, *p2, *p3;
  59         p1 = p3 = list1;
  60         p2 = list2;
  61
  62         while ( *p1 != -1 && *p2 != -1 ) {
  63                 if (compare_uint64(p1, p2) == 0) {
  64                         *p3++ = *p1++;
  65                         p2++;
  66                 }
  67                 else {
  68                         while (compare_uint64(p1, p2) < 0) ++p1;
  69                         while (compare_uint64(p1, p2) > 0) ++p2;
  70                 }
  71         }
  72         *p3 = -1;
  73         return p3 - list1;
  74 }
  75
  76
  77 // Darkside attack (hf mf mifare)
  78 static uint32_t nonce2key(uint32_t uid, uint32_t nt, uint32_t nr, uint32_t ar, uint64_t par_info, uint64_t ks_info, uint64_t **keys) {
  79         struct Crypto1State *states;
  80         uint32_t i, pos;
  81         uint8_t bt, ks3x[8], par[8][8];
  82         uint64_t key_recovered;
  83         uint64_t *keylist;
  84
  85         // Reset the last three significant bits of the reader nonce
  86         nr &= 0xffffff1f;
  87
  88         for (pos=0; pos<8; pos++) {
  89                 ks3x[7-pos] = (ks_info >> (pos*8)) & 0x0f;
  90                 bt = (par_info >> (pos*8)) & 0xff;
  91                 for (i=0; i<8; i++)     {
  92                                 par[7-pos][i] = (bt >> i) & 0x01;
  93                 }
  94         }
  95
  96         states = lfsr_common_prefix(nr, ar, ks3x, par, (par_info == 0));
  97
  98         if (states == NULL) {
  99                 *keys = NULL;
 100                 return 0;
 101         }
 102
 103         keylist = (uint64_t*)states;
 104
 105         for (i = 0; keylist[i]; i++) {
 106                 lfsr_rollback_word(states+i, uid^nt, 0);
 107                 crypto1_get_lfsr(states+i, &key_recovered);
 108                 keylist[i] = key_recovered;
 109         }
 110         keylist[i] = -1;
 111
 112         *keys = keylist;
 113         return i;
 114 }
 115
 116
 117 int mfDarkside(uint64_t *key)
 118 {
 119         uint32_t uid = 0;
 120         uint32_t nt = 0, nr = 0, ar = 0;
 121         uint64_t par_list = 0, ks_list = 0;
 122         uint64_t *keylist = NULL, *last_keylist = NULL;
 123         uint32_t keycount = 0;
 124         int16_t isOK = 0;
 125
 126         UsbCommand c = {CMD_READER_MIFARE, {true, 0, 0}};
 127
 128         // message
 129         printf("-------------------------------------------------------------------------\n");
 130         printf("Executing command. Expected execution time: 25sec on average\n");
 131         printf("Press button on the proxmark3 device to abort both proxmark3 and client.\n");
 132         printf("-------------------------------------------------------------------------\n");
 133
 134
 135         while (true) {
 136                 clearCommandBuffer();
 137                 SendCommand(&c);
 138
 139                 //flush queue
 140                 while (ukbhit()) {
 141                         int c = getchar(); (void) c;
 142                 }
 143
 144                 // wait cycle
 145                 while (true) {
 146                         printf(".");
 147                         fflush(stdout);
 148                         if (ukbhit()) {
 149                                 return -5;
 150                                 break;
 151                         }
 152
 153                         UsbCommand resp;
 154                         if (WaitForResponseTimeout(CMD_ACK, &resp, 1000)) {
 155                                 isOK  = resp.arg[0];
 156                                 if (isOK < 0) {
 157                                         return isOK;
 158                                 }
 159                                 uid = (uint32_t)bytes_to_num(resp.d.asBytes +  0, 4);
 160                                 nt =  (uint32_t)bytes_to_num(resp.d.asBytes +  4, 4);
 161                                 par_list = bytes_to_num(resp.d.asBytes +  8, 8);
 162                                 ks_list = bytes_to_num(resp.d.asBytes +  16, 8);
 163                                 nr = (uint32_t)bytes_to_num(resp.d.asBytes + 24, 4);
 164                                 ar = (uint32_t)bytes_to_num(resp.d.asBytes + 28, 4);
 165                                 break;
 166                         }
 167                 }
 168
 169                 if (par_list == 0 && c.arg[0] == true) {
 170                         PrintAndLog("Parity is all zero. Most likely this card sends NACK on every failed authentication.");
 171                 }
 172                 c.arg[0] = false;
 173
 174                 keycount = nonce2key(uid, nt, nr, ar, par_list, ks_list, &keylist);
 175
 176                 if (keycount == 0) {
 177                         PrintAndLog("Key not found (lfsr_common_prefix list is null). Nt=%08x", nt);
 178                         PrintAndLog("This is expected to happen in 25%% of all cases. Trying again with a different reader nonce...");
 179                         continue;
 180                 }
 181
 182                 if (par_list == 0) {
 183                         qsort(keylist, keycount, sizeof(*keylist), compare_uint64);
 184                         keycount = intersection(last_keylist, keylist);
 185                         if (keycount == 0) {
 186                                 free(last_keylist);
 187                                 last_keylist = keylist;
 188                                 continue;
 189                         }
 190                 }
 191
 192                 if (keycount > 1) {
 193                         PrintAndLog("Found %u possible keys. Trying to authenticate with each of them ...\n", keycount);
 194                 } else {
 195                         PrintAndLog("Found a possible key. Trying to authenticate...\n");
 196                 }
 197
 198                 *key = -1;
 199                 uint8_t keyBlock[USB_CMD_DATA_SIZE];
 200                 int max_keys = USB_CMD_DATA_SIZE/6;
 201                 for (int i = 0; i < keycount; i += max_keys) {
 202                         int size = keycount - i > max_keys ? max_keys : keycount - i;
 203                         for (int j = 0; j < size; j++) {
 204                                 if (par_list == 0) {
 205                                         num_to_bytes(last_keylist[i*max_keys + j], 6, keyBlock+(j*6));
 206                                 } else {
 207                                         num_to_bytes(keylist[i*max_keys + j], 6, keyBlock+(j*6));
 208                                 }
 209                         }
 210                         if (!mfCheckKeys(0, 0, false, size, keyBlock, key)) {
 211                                 break;
 212                         }
 213                 }
 214
 215                 if (*key != -1) {
 216                         free(last_keylist);
 217                         free(keylist);
 218                         break;
 219                 } else {
 220                         PrintAndLog("Authentication failed. Trying again...");
 221                         free(last_keylist);
 222                         last_keylist = keylist;
 223                 }
 224         }
 225
 226         return 0;
 227 }
 228
 229
 230 int mfCheckKeys (uint8_t blockNo, uint8_t keyType, bool clear_trace, uint8_t keycnt, uint8_t * keyBlock, uint64_t * key){
 231
 232         *key = -1;
 233
 234         UsbCommand c = {CMD_MIFARE_CHKKEYS, {((blockNo & 0xff) | ((keyType & 0xff) << 8)), clear_trace, keycnt}};
 235         memcpy(c.d.asBytes, keyBlock, 6 * keycnt);
 236         SendCommand(&c);
 237
 238         UsbCommand resp;
 239         if (!WaitForResponseTimeout(CMD_ACK,&resp,3000)) return 1;
 240         if ((resp.arg[0] & 0xff) != 0x01) return 2;
 241         *key = bytes_to_num(resp.d.asBytes, 6);
 242         return 0;
 243 }
 244
 245 int mfCheckKeysSec(uint8_t sectorCnt, uint8_t keyType, uint8_t timeout14a, bool clear_trace, uint8_t keycnt, uint8_t * keyBlock, sector_t * e_sector){
 246
 247         uint8_t keyPtr = 0;
 248
 249         if (e_sector == NULL)
 250                 return -1;
 251
 252         UsbCommand c = {CMD_MIFARE_CHKKEYS, {((sectorCnt & 0xff) | ((keyType & 0xff) << 8)), (clear_trace | 0x02)|((timeout14a & 0xff) << 8), keycnt}};
 253         memcpy(c.d.asBytes, keyBlock, 6 * keycnt);
 254         SendCommand(&c);
 255
 256         UsbCommand resp;
 257         if (!WaitForResponseTimeoutW(CMD_ACK, &resp, MAX(3000, 1000 + 13 * sectorCnt * keycnt * (keyType == 2 ? 2 : 1)), false)) return 1; // timeout: 13 ms / fail auth
 258         if ((resp.arg[0] & 0xff) != 0x01) return 2;
 259
 260         bool foundAKey = false;
 261         for(int sec = 0; sec < sectorCnt; sec++){
 262                 for(int keyAB = 0; keyAB < 2; keyAB++){
 263                         keyPtr = *(resp.d.asBytes + keyAB * 40 + sec);
 264                         if (keyPtr){
 265                                 e_sector[sec].foundKey[keyAB] = true;
 266                                 e_sector[sec].Key[keyAB] = bytes_to_num(keyBlock + (keyPtr - 1) * 6, 6);
 267                                 foundAKey = true;
 268                         }
 269                 }
 270         }
 271         return foundAKey ? 0 : 3;
 272 }
 273
 274 // Compare 16 Bits out of cryptostate
 275 int Compare16Bits(const void * a, const void * b) {
 276         if ((*(uint64_t*)b & 0x00ff000000ff0000) == (*(uint64_t*)a & 0x00ff000000ff0000)) return 0;
 277         else if ((*(uint64_t*)b & 0x00ff000000ff0000) > (*(uint64_t*)a & 0x00ff000000ff0000)) return 1;
 278         else return -1;
 279 }
 280
 281 typedef
 282         struct {
 283                 union {
 284                         struct Crypto1State *slhead;
 285                         uint64_t *keyhead;
 286                 } head;
 287                 union {
 288                         struct Crypto1State *sltail;
 289                         uint64_t *keytail;
 290                 } tail;
 291                 uint32_t len;
 292                 uint32_t uid;
 293                 uint32_t blockNo;
 294                 uint32_t keyType;
 295                 uint32_t nt;
 296                 uint32_t ks1;
 297         } StateList_t;
 298
 299
 300 // wrapper function for multi-threaded lfsr_recovery32
 301 void
 302 #ifdef __has_attribute
 303 #if __has_attribute(force_align_arg_pointer)
 304 __attribute__((force_align_arg_pointer))
 305 #endif
 306 #endif
 307 *nested_worker_thread(void *arg)
 308 {
 309         struct Crypto1State *p1;
 310         StateList_t *statelist = arg;
 311
 312         statelist->head.slhead = lfsr_recovery32(statelist->ks1, statelist->nt ^ statelist->uid);
 313         for (p1 = statelist->head.slhead; *(uint64_t *)p1 != 0; p1++);
 314         statelist->len = p1 - statelist->head.slhead;
 315         statelist->tail.sltail = --p1;
 316         qsort(statelist->head.slhead, statelist->len, sizeof(uint64_t), Compare16Bits);
 317
 318         return statelist->head.slhead;
 319 }
 320
 321
 322 int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t *resultKey, bool calibrate)
 323 {
 324         uint16_t i;
 325         uint32_t uid;
 326         UsbCommand resp;
 327
 328         StateList_t statelists[2];
 329         struct Crypto1State *p1, *p2, *p3, *p4;
 330
 331         // flush queue
 332         (void)WaitForResponseTimeout(CMD_ACK,NULL,100);
 333
 334         UsbCommand c = {CMD_MIFARE_NESTED, {blockNo + keyType * 0x100, trgBlockNo + trgKeyType * 0x100, calibrate}};
 335         memcpy(c.d.asBytes, key, 6);
 336         SendCommand(&c);
 337
 338         if (!WaitForResponseTimeout(CMD_ACK, &resp, 1500)) {
 339                 return -1;
 340         }
 341
 342         if (resp.arg[0]) {
 343                 return resp.arg[0];  // error during nested
 344         }
 345
 346         memcpy(&uid, resp.d.asBytes, 4);
 347         PrintAndLog("uid:%08x trgbl=%d trgkey=%x", uid, (uint16_t)resp.arg[2] & 0xff, (uint16_t)resp.arg[2] >> 8);
 348
 349         for (i = 0; i < 2; i++) {
 350                 statelists[i].blockNo = resp.arg[2] & 0xff;
 351                 statelists[i].keyType = (resp.arg[2] >> 8) & 0xff;
 352                 statelists[i].uid = uid;
 353                 memcpy(&statelists[i].nt,  (void *)(resp.d.asBytes + 4 + i * 8 + 0), 4);
 354                 memcpy(&statelists[i].ks1, (void *)(resp.d.asBytes + 4 + i * 8 + 4), 4);
 355         }
 356
 357         // calc keys
 358
 359         pthread_t thread_id[2];
 360
 361         // create and run worker threads
 362         for (i = 0; i < 2; i++) {
 363                 pthread_create(thread_id + i, NULL, nested_worker_thread, &statelists[i]);
 364         }
 365
 366         // wait for threads to terminate:
 367         for (i = 0; i < 2; i++) {
 368                 pthread_join(thread_id[i], (void*)&statelists[i].head.slhead);
 369         }
 370
 371
 372         // the first 16 Bits of the cryptostate already contain part of our key.
 373         // Create the intersection of the two lists based on these 16 Bits and
 374         // roll back the cryptostate
 375         p1 = p3 = statelists[0].head.slhead;
 376         p2 = p4 = statelists[1].head.slhead;
 377         while (p1 <= statelists[0].tail.sltail && p2 <= statelists[1].tail.sltail) {
 378                 if (Compare16Bits(p1, p2) == 0) {
 379                         struct Crypto1State savestate, *savep = &savestate;
 380                         savestate = *p1;
 381                         while(Compare16Bits(p1, savep) == 0 && p1 <= statelists[0].tail.sltail) {
 382                                 *p3 = *p1;
 383                                 lfsr_rollback_word(p3, statelists[0].nt ^ statelists[0].uid, 0);
 384                                 p3++;
 385                                 p1++;
 386                         }
 387                         savestate = *p2;
 388                         while(Compare16Bits(p2, savep) == 0 && p2 <= statelists[1].tail.sltail) {
 389                                 *p4 = *p2;
 390                                 lfsr_rollback_word(p4, statelists[1].nt ^ statelists[1].uid, 0);
 391                                 p4++;
 392                                 p2++;
 393                         }
 394                 }
 395                 else {
 396                         while (Compare16Bits(p1, p2) == -1) p1++;
 397                         while (Compare16Bits(p1, p2) == 1) p2++;
 398                 }
 399         }
 400         *(uint64_t*)p3 = -1;
 401         *(uint64_t*)p4 = -1;
 402         statelists[0].len = p3 - statelists[0].head.slhead;
 403         statelists[1].len = p4 - statelists[1].head.slhead;
 404         statelists[0].tail.sltail=--p3;
 405         statelists[1].tail.sltail=--p4;
 406
 407         // the statelists now contain possible keys. The key we are searching for must be in the
 408         // intersection of both lists. Create the intersection:
 409         qsort(statelists[0].head.keyhead, statelists[0].len, sizeof(uint64_t), compare_uint64);
 410         qsort(statelists[1].head.keyhead, statelists[1].len, sizeof(uint64_t), compare_uint64);
 411         statelists[0].len = intersection(statelists[0].head.keyhead, statelists[1].head.keyhead);
 412
 413         memset(resultKey, 0, 6);
 414         // The list may still contain several key candidates. Test each of them with mfCheckKeys
 415         for (i = 0; i < statelists[0].len; i++) {
 416                 uint8_t keyBlock[6];
 417                 uint64_t key64;
 418                 crypto1_get_lfsr(statelists[0].head.slhead + i, &key64);
 419                 num_to_bytes(key64, 6, keyBlock);
 420                 key64 = 0;
 421                 if (!mfCheckKeys(statelists[0].blockNo, statelists[0].keyType, false, 1, keyBlock, &key64)) {
 422                         num_to_bytes(key64, 6, resultKey);
 423                         break;
 424                 }
 425         }
 426
 427         free(statelists[0].head.slhead);
 428         free(statelists[1].head.slhead);
 429
 430         return 0;
 431 }
 432
 433 // MIFARE
 434 int mfReadSector(uint8_t sectorNo, uint8_t keyType, uint8_t *key, uint8_t *data) {
 435
 436     UsbCommand c = {CMD_MIFARE_READSC, {sectorNo, keyType, 0}};
 437     memcpy(c.d.asBytes, key, 6);
 438     clearCommandBuffer();
 439     SendCommand(&c);
 440
 441     UsbCommand resp;
 442     if (WaitForResponseTimeout(CMD_ACK, &resp, 1500)) {
 443         uint8_t isOK  = resp.arg[0] & 0xff;
 444
 445         if (isOK) {
 446             memcpy(data, resp.d.asBytes, mfNumBlocksPerSector(sectorNo) * 16);
 447             return 0;
 448         } else {
 449             return 1;
 450         }
 451     } else {
 452         PrintAndLogEx(ERR, "Command execute timeout");
 453         return 2;
 454     }
 455
 456     return 0;
 457 }
 458
 459 // EMULATOR
 460
 461 int mfEmlGetMem(uint8_t *data, int blockNum, int blocksCount) {
 462         UsbCommand c = {CMD_MIFARE_EML_MEMGET, {blockNum, blocksCount, 0}};
 463         SendCommand(&c);
 464
 465   UsbCommand resp;
 466         if (!WaitForResponseTimeout(CMD_ACK,&resp,1500)) return 1;
 467         memcpy(data, resp.d.asBytes, blocksCount * 16);
 468         return 0;
 469 }
 470
 471 int mfEmlSetMem(uint8_t *data, int blockNum, int blocksCount) {
 472         UsbCommand c = {CMD_MIFARE_EML_MEMSET, {blockNum, blocksCount, 0}};
 473         memcpy(c.d.asBytes, data, blocksCount * 16);
 474         SendCommand(&c);
 475         return 0;
 476 }
 477
 478 // "MAGIC" CARD
 479
 480 int mfCGetBlock(uint8_t blockNo, uint8_t *data, uint8_t params) {
 481         uint8_t isOK = 0;
 482
 483         UsbCommand c = {CMD_MIFARE_CGETBLOCK, {params, 0, blockNo}};
 484         SendCommand(&c);
 485
 486         UsbCommand resp;
 487         if (WaitForResponseTimeout(CMD_ACK,&resp,1500)) {
 488                 isOK  = resp.arg[0] & 0xff;
 489                 memcpy(data, resp.d.asBytes, 16);
 490                 if (!isOK) return 2;
 491         } else {
 492                 PrintAndLog("Command execute timeout");
 493                 return 1;
 494         }
 495         return 0;
 496 }
 497
 498 int mfCSetBlock(uint8_t blockNo, uint8_t *data, uint8_t *uid, bool wantWipe, uint8_t params) {
 499
 500         uint8_t isOK = 0;
 501         UsbCommand c = {CMD_MIFARE_CSETBLOCK, {wantWipe, params & (0xFE | (uid == NULL ? 0:1)), blockNo}};
 502         memcpy(c.d.asBytes, data, 16);
 503         SendCommand(&c);
 504
 505         UsbCommand resp;
 506         if (WaitForResponseTimeout(CMD_ACK, &resp, 1500)) {
 507                 isOK  = resp.arg[0] & 0xff;
 508                 if (uid != NULL)
 509                         memcpy(uid, resp.d.asBytes, 4);
 510                 if (!isOK)
 511                         return 2;
 512         } else {
 513                 PrintAndLog("Command execute timeout");
 514                 return 1;
 515         }
 516
 517         return 0;
 518 }
 519
 520 int mfCWipe(uint32_t numSectors, bool gen1b, bool wantWipe, bool wantFill) {
 521         uint8_t isOK = 0;
 522         uint8_t cmdParams = wantWipe + wantFill * 0x02 + gen1b * 0x04;
 523         UsbCommand c = {CMD_MIFARE_CWIPE, {numSectors, cmdParams, 0}};
 524         SendCommand(&c);
 525
 526         UsbCommand resp;
 527         WaitForResponse(CMD_ACK,&resp);
 528         isOK  = resp.arg[0] & 0xff;
 529
 530         return isOK;
 531 }
 532
 533 int mfCSetUID(uint8_t *uid, uint8_t *atqa, uint8_t *sak, uint8_t *oldUID) {
 534         uint8_t oldblock0[16] = {0x00};
 535         uint8_t block0[16] = {0x00};
 536         int gen = 0, res;
 537
 538         gen = mfCIdentify();
 539
 540         /* generation 1a magic card by default */
 541         uint8_t cmdParams = CSETBLOCK_SINGLE_OPER;
 542         if (gen == 2) {
 543                 /* generation 1b magic card */
 544                 cmdParams = CSETBLOCK_SINGLE_OPER | CSETBLOCK_MAGIC_1B;
 545         }
 546
 547         res = mfCGetBlock(0, oldblock0, cmdParams);
 548
 549         if (res == 0) {
 550                 memcpy(block0, oldblock0, 16);
 551                 PrintAndLog("old block 0:  %s", sprint_hex(block0,16));
 552         } else {
 553                 PrintAndLog("Couldn't get old data. Will write over the last bytes of Block 0.");
 554         }
 555
 556         // fill in the new values
 557         // UID
 558         memcpy(block0, uid, 4);
 559         // Mifare UID BCC
 560         block0[4] = block0[0] ^ block0[1] ^ block0[2] ^ block0[3];
 561         // mifare classic SAK(byte 5) and ATQA(byte 6 and 7, reversed)
 562         if (sak != NULL)
 563                 block0[5] = sak[0];
 564         if (atqa != NULL) {
 565                 block0[6] = atqa[1];
 566                 block0[7] = atqa[0];
 567         }
 568         PrintAndLog("new block 0:  %s", sprint_hex(block0, 16));
 569
 570         res = mfCSetBlock(0, block0, oldUID, false, cmdParams);
 571         if (res) {
 572                 PrintAndLog("Can't set block 0. Error: %d", res);
 573                 return res;
 574         }
 575
 576         return 0;
 577 }
 578
 579 int mfCIdentify() {
 580         UsbCommand c = {CMD_MIFARE_CIDENT, {0, 0, 0}};
 581         SendCommand(&c);
 582         UsbCommand resp;
 583         WaitForResponse(CMD_ACK,&resp);
 584
 585         uint8_t isGeneration = resp.arg[0] & 0xff;
 586         switch( isGeneration ){
 587                 case 1: PrintAndLog("Chinese magic backdoor commands (GEN 1a) detected"); break;
 588                 case 2: PrintAndLog("Chinese magic backdoor command (GEN 1b) detected"); break;
 589                 default: PrintAndLog("No chinese magic backdoor command detected"); break;
 590         }
 591
 592         return (int) isGeneration;
 593 }
 594
 595
 596 // SNIFFER
 597
 598 // constants
 599 static uint8_t trailerAccessBytes[4] = {0x08, 0x77, 0x8F, 0x00};
 600
 601 // variables
 602 char logHexFileName[FILE_PATH_SIZE] = {0x00};
 603 static uint8_t traceCard[4096] = {0x00};
 604 static char traceFileName[FILE_PATH_SIZE] = {0x00};
 605 static int traceState = TRACE_IDLE;
 606 static uint8_t traceCurBlock = 0;
 607 static uint8_t traceCurKey = 0;
 608
 609 struct Crypto1State *traceCrypto1 = NULL;
 610
 611 struct Crypto1State *revstate;
 612 uint64_t lfsr;
 613 uint64_t ui64Key;
 614 uint32_t ks2;
 615 uint32_t ks3;
 616
 617 uint32_t uid;       // serial number
 618 uint32_t nt;        // tag challenge
 619 uint32_t nt_enc;    // encrypted tag challenge
 620 uint8_t nt_enc_par; // encrypted tag challenge parity
 621 uint32_t nr_enc;    // encrypted reader challenge
 622 uint32_t ar_enc;    // encrypted reader response
 623 uint8_t ar_enc_par; // encrypted reader response parity
 624 uint32_t at_enc;    // encrypted tag response
 625 uint8_t at_enc_par; // encrypted tag response parity
 626
 627 int isTraceCardEmpty(void) {
 628         return ((traceCard[0] == 0) && (traceCard[1] == 0) && (traceCard[2] == 0) && (traceCard[3] == 0));
 629 }
 630
 631 int isBlockEmpty(int blockN) {
 632         for (int i = 0; i < 16; i++)
 633                 if (traceCard[blockN * 16 + i] != 0) return 0;
 634
 635         return 1;
 636 }
 637
 638 int isBlockTrailer(int blockN) {
 639  return ((blockN & 0x03) == 0x03);
 640 }
 641
 642 int saveTraceCard(void) {
 643         FILE * f;
 644
 645         if ((!strlen(traceFileName)) || (isTraceCardEmpty())) return 0;
 646
 647         f = fopen(traceFileName, "w+");
 648         if ( !f ) return 1;
 649
 650         for (int i = 0; i < 64; i++) {  // blocks
 651                 for (int j = 0; j < 16; j++)  // bytes
 652                         fprintf(f, "%02x", *(traceCard + i * 16 + j));
 653                 if (i < 63)
 654                         fprintf(f,"\n");
 655         }
 656         fclose(f);
 657         return 0;
 658 }
 659
 660 int loadTraceCard(uint8_t *tuid) {
 661         FILE * f;
 662         char buf[64] = {0x00};
 663         uint8_t buf8[64] = {0x00};
 664         int i, blockNum;
 665
 666         if (!isTraceCardEmpty())
 667                 saveTraceCard();
 668
 669         memset(traceCard, 0x00, 4096);
 670         memcpy(traceCard, tuid + 3, 4);
 671
 672         FillFileNameByUID(traceFileName, tuid, ".eml", 7);
 673
 674         f = fopen(traceFileName, "r");
 675         if (!f) return 1;
 676
 677         blockNum = 0;
 678
 679         while(!feof(f)){
 680
 681                 memset(buf, 0, sizeof(buf));
 682                 if (fgets(buf, sizeof(buf), f) == NULL) {
 683                         PrintAndLog("File reading error.");
 684                         fclose(f);
 685                         return 2;
 686         }
 687
 688                 if (strlen(buf) < 32){
 689                         if (feof(f)) break;
 690                         PrintAndLog("File content error. Block data must include 32 HEX symbols");
 691                         fclose(f);
 692                         return 2;
 693                 }
 694                 for (i = 0; i < 32; i += 2)
 695                         sscanf(&buf[i], "%02x", (unsigned int *)&buf8[i / 2]);
 696
 697                 memcpy(traceCard + blockNum * 16, buf8, 16);
 698
 699                 blockNum++;
 700         }
 701         fclose(f);
 702
 703         return 0;
 704 }
 705
 706 int mfTraceInit(uint8_t *tuid, uint8_t *atqa, uint8_t sak, bool wantSaveToEmlFile) {
 707
 708         if (traceCrypto1)
 709                 crypto1_destroy(traceCrypto1);
 710
 711         traceCrypto1 = NULL;
 712
 713         if (wantSaveToEmlFile)
 714                 loadTraceCard(tuid);
 715
 716         traceCard[4] = traceCard[0] ^ traceCard[1] ^ traceCard[2] ^ traceCard[3];
 717         traceCard[5] = sak;
 718         memcpy(&traceCard[6], atqa, 2);
 719         traceCurBlock = 0;
 720         uid = bytes_to_num(tuid + 3, 4);
 721
 722         traceState = TRACE_IDLE;
 723
 724         return 0;
 725 }
 726
 727 void mf_crypto1_decrypt(struct Crypto1State *pcs, uint8_t *data, int len, bool isEncrypted){
 728         uint8_t bt = 0;
 729         int i;
 730
 731         if (len != 1) {
 732                 for (i = 0; i < len; i++)
 733                         data[i] = crypto1_byte(pcs, 0x00, isEncrypted) ^ data[i];
 734         } else {
 735                 bt = 0;
 736                 for (i = 0; i < 4; i++)
 737                         bt |= (crypto1_bit(pcs, 0, isEncrypted) ^ BIT(data[0], i)) << i;
 738
 739                 data[0] = bt;
 740         }
 741         return;
 742 }
 743
 744 bool NTParityCheck(uint32_t ntx) {
 745         if (
 746                 (oddparity8(ntx >> 8 & 0xff) ^ (ntx & 0x01) ^ ((nt_enc_par >> 5) & 0x01) ^ (nt_enc & 0x01)) ||
 747                 (oddparity8(ntx >> 16 & 0xff) ^ (ntx >> 8 & 0x01) ^ ((nt_enc_par >> 6) & 0x01) ^ (nt_enc >> 8 & 0x01)) ||
 748                 (oddparity8(ntx >> 24 & 0xff) ^ (ntx >> 16 & 0x01) ^ ((nt_enc_par >> 7) & 0x01) ^ (nt_enc >> 16 & 0x01))
 749                 )
 750                 return false;
 751
 752         uint32_t ar = prng_successor(ntx, 64);
 753         if (
 754                 (oddparity8(ar >> 8 & 0xff) ^ (ar & 0x01) ^ ((ar_enc_par >> 5) & 0x01) ^ (ar_enc & 0x01)) ||
 755                 (oddparity8(ar >> 16 & 0xff) ^ (ar >> 8 & 0x01) ^ ((ar_enc_par >> 6) & 0x01) ^ (ar_enc >> 8 & 0x01)) ||
 756                 (oddparity8(ar >> 24 & 0xff) ^ (ar >> 16 & 0x01) ^ ((ar_enc_par >> 7) & 0x01) ^ (ar_enc >> 16 & 0x01))
 757                 )
 758                 return false;
 759
 760         uint32_t at = prng_successor(ntx, 96);
 761         if (
 762                 (oddparity8(ar & 0xff) ^ (at >> 24 & 0x01) ^ ((ar_enc_par >> 4) & 0x01) ^ (at_enc >> 24 & 0x01)) ||
 763                 (oddparity8(at >> 8 & 0xff) ^ (at & 0x01) ^ ((at_enc_par >> 5) & 0x01) ^ (at_enc & 0x01)) ||
 764                 (oddparity8(at >> 16 & 0xff) ^ (at >> 8 & 0x01) ^ ((at_enc_par >> 6) & 0x01) ^ (at_enc >> 8 & 0x01)) ||
 765                 (oddparity8(at >> 24 & 0xff) ^ (at >> 16 & 0x01) ^ ((at_enc_par >> 7) & 0x01) ^ (at_enc >> 16 & 0x01))
 766                 )
 767                 return false;
 768
 769         return true;
 770 }
 771
 772
 773 int mfTraceDecode(uint8_t *data_src, int len, uint8_t parity, bool wantSaveToEmlFile) {
 774         uint8_t data[64];
 775
 776         if (traceState == TRACE_ERROR) return 1;
 777         if (len > 64) {
 778                 traceState = TRACE_ERROR;
 779                 return 1;
 780         }
 781
 782         memcpy(data, data_src, len);
 783         if ((traceCrypto1) && ((traceState == TRACE_IDLE) || (traceState > TRACE_AUTH_OK))) {
 784                 mf_crypto1_decrypt(traceCrypto1, data, len, 0);
 785                 uint8_t parity[16];
 786                 oddparitybuf(data, len, parity);
 787                 PrintAndLog("dec> %s [%s]", sprint_hex(data, len), printBitsPar(parity, len));
 788                 AddLogHex(logHexFileName, "dec> ", data, len);
 789         }
 790
 791         switch (traceState) {
 792         case TRACE_IDLE:
 793                 // check packet crc16!
 794                 if ((len >= 4) && (!CheckCrc14443(CRC_14443_A, data, len))) {
 795                         PrintAndLog("dec> CRC ERROR!!!");
 796                         AddLogLine(logHexFileName, "dec> ", "CRC ERROR!!!");
 797                         traceState = TRACE_ERROR;  // do not decrypt the next commands
 798                         return 1;
 799                 }
 800
 801                 // AUTHENTICATION
 802                 if ((len ==4) && ((data[0] == 0x60) || (data[0] == 0x61))) {
 803                         traceState = TRACE_AUTH1;
 804                         traceCurBlock = data[1];
 805                         traceCurKey = data[0] == 60 ? 1:0;
 806                         return 0;
 807                 }
 808
 809                 // READ
 810                 if ((len ==4) && ((data[0] == 0x30))) {
 811                         traceState = TRACE_READ_DATA;
 812                         traceCurBlock = data[1];
 813                         return 0;
 814                 }
 815
 816                 // WRITE
 817                 if ((len ==4) && ((data[0] == 0xA0))) {
 818                         traceState = TRACE_WRITE_OK;
 819                         traceCurBlock = data[1];
 820                         return 0;
 821                 }
 822
 823                 // HALT
 824                 if ((len ==4) && ((data[0] == 0x50) && (data[1] == 0x00))) {
 825                         traceState = TRACE_ERROR;  // do not decrypt the next commands
 826                         return 0;
 827                 }
 828
 829                 return 0;
 830         break;
 831
 832         case TRACE_READ_DATA:
 833                 if (len == 18) {
 834                         traceState = TRACE_IDLE;
 835
 836                         if (isBlockTrailer(traceCurBlock)) {
 837                                 memcpy(traceCard + traceCurBlock * 16 + 6, data + 6, 4);
 838                         } else {
 839                                 memcpy(traceCard + traceCurBlock * 16, data, 16);
 840                         }
 841                         if (wantSaveToEmlFile) saveTraceCard();
 842                         return 0;
 843                 } else {
 844                         traceState = TRACE_ERROR;
 845                         return 1;
 846                 }
 847         break;
 848
 849         case TRACE_WRITE_OK:
 850                 if ((len == 1) && (data[0] == 0x0a)) {
 851                         traceState = TRACE_WRITE_DATA;
 852
 853                         return 0;
 854                 } else {
 855                         traceState = TRACE_ERROR;
 856                         return 1;
 857                 }
 858         break;
 859
 860         case TRACE_WRITE_DATA:
 861                 if (len == 18) {
 862                         traceState = TRACE_IDLE;
 863
 864                         memcpy(traceCard + traceCurBlock * 16, data, 16);
 865                         if (wantSaveToEmlFile) saveTraceCard();
 866                         return 0;
 867                 } else {
 868                         traceState = TRACE_ERROR;
 869                         return 1;
 870                 }
 871         break;
 872
 873         case TRACE_AUTH1:
 874                 if (len == 4) {
 875                         traceState = TRACE_AUTH2;
 876                         if (!traceCrypto1) {
 877                                 nt = bytes_to_num(data, 4);
 878                         } else {
 879                                 nt_enc = bytes_to_num(data, 4);
 880                                 nt_enc_par = parity;
 881                         }
 882                         return 0;
 883                 } else {
 884                         traceState = TRACE_ERROR;
 885                         return 1;
 886                 }
 887         break;
 888
 889         case TRACE_AUTH2:
 890                 if (len == 8) {
 891                         traceState = TRACE_AUTH_OK;
 892
 893                         nr_enc = bytes_to_num(data, 4);
 894                         ar_enc = bytes_to_num(data + 4, 4);
 895                         ar_enc_par = parity << 4;
 896                         return 0;
 897                 } else {
 898                         traceState = TRACE_ERROR;
 899                         return 1;
 900                 }
 901         break;
 902
 903         case TRACE_AUTH_OK:
 904                 if (len ==4) {
 905                         traceState = TRACE_IDLE;
 906
 907                         at_enc = bytes_to_num(data, 4);
 908                         at_enc_par = parity;
 909                         if (!traceCrypto1) {
 910
 911                                 //  decode key here)
 912                                 ks2 = ar_enc ^ prng_successor(nt, 64);
 913                                 ks3 = at_enc ^ prng_successor(nt, 96);
 914                                 revstate = lfsr_recovery64(ks2, ks3);
 915                                 lfsr_rollback_word(revstate, 0, 0);
 916                                 lfsr_rollback_word(revstate, 0, 0);
 917                                 lfsr_rollback_word(revstate, nr_enc, 1);
 918                                 lfsr_rollback_word(revstate, uid ^ nt, 0);
 919
 920                                 crypto1_get_lfsr(revstate, &lfsr);
 921                                 crypto1_destroy(revstate);
 922                                 ui64Key = lfsr;
 923                                 printf("key> probable key:%x%x Prng:%s ks2:%08x ks3:%08x\n",
 924                                         (unsigned int)((lfsr & 0xFFFFFFFF00000000) >> 32), (unsigned int)(lfsr & 0xFFFFFFFF),
 925                                         validate_prng_nonce(nt) ? "WEAK": "HARDEND",
 926                                         ks2,
 927                                         ks3);
 928                                 AddLogUint64(logHexFileName, "key> ", lfsr);
 929                         } else {
 930                                 if (validate_prng_nonce(nt)) {
 931                                         struct Crypto1State *pcs;
 932                                         pcs = crypto1_create(ui64Key);
 933                                         uint32_t nt1 = crypto1_word(pcs, nt_enc ^ uid, 1) ^ nt_enc;
 934                                         uint32_t ar = prng_successor(nt1, 64);
 935                                         uint32_t at = prng_successor(nt1, 96);
 936                                         printf("key> nested auth uid: %08x nt: %08x nt_parity: %s ar: %08x at: %08x\n", uid, nt1, printBitsPar(&nt_enc_par, 4), ar, at);
 937                                         uint32_t nr1 = crypto1_word(pcs, nr_enc, 1) ^ nr_enc;
 938                                         uint32_t ar1 = crypto1_word(pcs, 0, 0) ^ ar_enc;
 939                                         uint32_t at1 = crypto1_word(pcs, 0, 0) ^ at_enc;
 940                                         crypto1_destroy(pcs);
 941                                         printf("key> the same key test. nr1: %08x ar1: %08x at1: %08x \n", nr1, ar1, at1);
 942
 943                                         if (NTParityCheck(nt1))
 944                                                 printf("key> the same key test OK. key=%x%x\n", (unsigned int)((ui64Key & 0xFFFFFFFF00000000) >> 32), (unsigned int)(ui64Key & 0xFFFFFFFF));
 945                                         else
 946                                                 printf("key> the same key test. check nt parity error.\n");
 947
 948                                         uint32_t ntc = prng_successor(nt, 90);
 949                                         uint32_t ntx = 0;
 950                                         int ntcnt = 0;
 951                                         for (int i = 0; i < 16383; i++) {
 952                                                 ntc = prng_successor(ntc, 1);
 953                                                 if (NTParityCheck(ntc)){
 954                                                         if (!ntcnt)
 955                                                                 ntx = ntc;
 956                                                         ntcnt++;
 957                                                 }
 958                                         }
 959                                         if (ntcnt)
 960                                                 printf("key> nt candidate=%08x nonce distance=%d candidates count=%d\n", ntx, nonce_distance(nt, ntx), ntcnt);
 961                                         else
 962                                                 printf("key> don't have any nt candidate( \n");
 963
 964                                         nt = ntx;
 965                                         ks2 = ar_enc ^ prng_successor(ntx, 64);
 966                                         ks3 = at_enc ^ prng_successor(ntx, 96);
 967
 968                                         // decode key
 969                                         revstate = lfsr_recovery64(ks2, ks3);
 970                                         lfsr_rollback_word(revstate, 0, 0);
 971                                         lfsr_rollback_word(revstate, 0, 0);
 972                                         lfsr_rollback_word(revstate, nr_enc, 1);
 973                                         lfsr_rollback_word(revstate, uid ^ nt, 0);
 974
 975                                         crypto1_get_lfsr(revstate, &lfsr);
 976                                         crypto1_destroy(revstate);
 977                                         ui64Key = lfsr;
 978                                         printf("key> probable key:%x%x  ks2:%08x ks3:%08x\n",
 979                                                 (unsigned int)((lfsr & 0xFFFFFFFF00000000) >> 32), (unsigned int)(lfsr & 0xFFFFFFFF),
 980                                                 ks2,
 981                                                 ks3);
 982                                         AddLogUint64(logHexFileName, "key> ", lfsr);
 983                                 } else {
 984                                         printf("key> hardnested not implemented!\n");
 985
 986                                         crypto1_destroy(traceCrypto1);
 987
 988                                         // not implemented
 989                                         traceState = TRACE_ERROR;
 990                                 }
 991                         }
 992
 993                         int blockShift = ((traceCurBlock & 0xFC) + 3) * 16;
 994                         if (isBlockEmpty((traceCurBlock & 0xFC) + 3)) memcpy(traceCard + blockShift + 6, trailerAccessBytes, 4);
 995
 996                         if (traceCurKey) {
 997                                 num_to_bytes(lfsr, 6, traceCard + blockShift + 10);
 998                         } else {
 999                                 num_to_bytes(lfsr, 6, traceCard + blockShift);
1000                         }
1001                         if (wantSaveToEmlFile) saveTraceCard();
1002
1003                         if (traceCrypto1) {
1004                                 crypto1_destroy(traceCrypto1);
1005                         }
1006
1007                         // set cryptosystem state
1008                         traceCrypto1 = lfsr_recovery64(ks2, ks3);
1009                         return 0;
1010                 } else {
1011                         traceState = TRACE_ERROR;
1012                         return 1;
1013                 }
1014         break;
1015
1016         default:
1017                 traceState = TRACE_ERROR;
1018                 return 1;
1019         }
1020
1021         return 0;
1022 }
1023
1024 // DECODING
1025
1026 int tryDecryptWord(uint32_t nt, uint32_t ar_enc, uint32_t at_enc, uint8_t *data, int len){
1027         /*
1028         uint32_t nt;      // tag challenge
1029         uint32_t ar_enc;  // encrypted reader response
1030         uint32_t at_enc;  // encrypted tag response
1031         */
1032         if (traceCrypto1) {
1033                 crypto1_destroy(traceCrypto1);
1034         }
1035         ks2 = ar_enc ^ prng_successor(nt, 64);
1036         ks3 = at_enc ^ prng_successor(nt, 96);
1037         traceCrypto1 = lfsr_recovery64(ks2, ks3);
1038
1039         mf_crypto1_decrypt(traceCrypto1, data, len, 0);
1040
1041         PrintAndLog("Decrypted data: [%s]", sprint_hex(data,len) );
1042         crypto1_destroy(traceCrypto1);
1043         return 0;
1044 }
1045
1046 /** validate_prng_nonce
1047  * Determine if nonce is deterministic. ie: Suspectable to Darkside attack.
1048  * returns
1049  *   true = weak prng
1050  *   false = hardend prng
1051  */
1052 bool validate_prng_nonce(uint32_t nonce) {
1053         uint16_t *dist = 0;
1054         uint16_t x, i;
1055
1056         dist = malloc(2 << 16);
1057         if(!dist)
1058                 return -1;
1059
1060         // init prng table:
1061         for (x = i = 1; i; ++i) {
1062                 dist[(x & 0xff) << 8 | x >> 8] = i;
1063                 x = x >> 1 | (x ^ x >> 2 ^ x >> 3 ^ x >> 5) << 15;
1064         }
1065
1066         uint32_t res = (65535 - dist[nonce >> 16] + dist[nonce & 0xffff]) % 65535;
1067
1068         free(dist);
1069         return (res == 16);
1070 }
1071
1072 /* Detect Tag Prng,
1073 * function performs a partial AUTH,  where it tries to authenticate against block0, key A, but only collects tag nonce.
1074 * the tag nonce is check to see if it has a predictable PRNG.
1075 * @returns
1076 *       TRUE if tag uses WEAK prng (ie Now the NACK bug also needs to be present for Darkside attack)
1077 *   FALSE is tag uses HARDEND prng (ie hardnested attack possible, with known key)
1078 */
1079 int DetectClassicPrng(void){
1080
1081         UsbCommand resp, respA;
1082         uint8_t cmd[] = {0x60, 0x00}; // MIFARE_AUTH_KEYA
1083         uint32_t flags = ISO14A_CONNECT | ISO14A_RAW | ISO14A_APPEND_CRC | ISO14A_NO_RATS;
1084
1085         UsbCommand c = {CMD_READER_ISO_14443a, {flags, sizeof(cmd), 0}};
1086         memcpy(c.d.asBytes, cmd, sizeof(cmd));
1087
1088         clearCommandBuffer();
1089         SendCommand(&c);
1090         if (!WaitForResponseTimeout(CMD_ACK, &resp, 2000)) {
1091         PrintAndLog("PRNG UID: Reply timeout.");
1092                 return -1;
1093         }
1094
1095         // if select tag failed.
1096         if (resp.arg[0] == 0) {
1097                 PrintAndLog("PRNG error: selecting tag failed, can't detect prng.");
1098                 return -1;
1099         }
1100
1101         if (!WaitForResponseTimeout(CMD_ACK, &respA, 5000)) {
1102         PrintAndLog("PRNG data: Reply timeout.");
1103                 return -1;
1104         }
1105
1106         // check respA
1107         if (respA.arg[0] != 4) {
1108                 PrintAndLog("PRNG data error: Wrong length: %d", respA.arg[0]);
1109                 return -1;
1110         }
1111
1112         uint32_t nonce = bytes_to_num(respA.d.asBytes, respA.arg[0]);
1113         return validate_prng_nonce(nonce);
1114 }