git.zerfleddert.de Git - proxmark3-svn/blob - armsrc/mifareutil.c

   1 //-----------------------------------------------------------------------------
   2 // Merlok, May 2011, 2012
   3 // Many authors, whom made it possible
   4 //
   5 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   6 // at your option, any later version. See the LICENSE.txt file for the text of
   7 // the license.
   8 //-----------------------------------------------------------------------------
   9 // Work with mifare cards.
  10 //-----------------------------------------------------------------------------
  11
  12 #include "proxmark3.h"
  13 #include "apps.h"
  14 #include "util.h"
  15 #include "string.h"
  16
  17 #include "iso14443crc.h"
  18 #include "iso14443a.h"
  19 #include "crapto1.h"
  20 #include "mifareutil.h"
  21
  22 int MF_DBGLEVEL = MF_DBG_ALL;
  23
  24 // memory management
  25 uint8_t* get_bigbufptr_recvrespbuf(void) {
  26         return (((uint8_t *)BigBuf) + RECV_RESP_OFFSET);
  27 }
  28 uint8_t* get_bigbufptr_recvcmdbuf(void) {
  29         return (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
  30 }
  31 uint8_t* get_bigbufptr_emlcardmem(void) {
  32         return (((uint8_t *)BigBuf) + CARD_MEMORY_OFFSET);
  33 }
  34
  35 // crypto1 helpers
  36 void mf_crypto1_decrypt(struct Crypto1State *pcs, uint8_t *data, int len){
  37         uint8_t bt = 0;
  38         int i;
  39
  40         if (len != 1) {
  41                 for (i = 0; i < len; i++)
  42                         data[i] = crypto1_byte(pcs, 0x00, 0) ^ data[i];
  43         } else {
  44                 bt = 0;
  45                 for (i = 0; i < 4; i++)
  46                         bt |= (crypto1_bit(pcs, 0, 0) ^ BIT(data[0], i)) << i;
  47
  48                 data[0] = bt;
  49         }
  50         return;
  51 }
  52
  53 void mf_crypto1_encrypt(struct Crypto1State *pcs, uint8_t *data, uint16_t len, uint8_t *par) {
  54         uint8_t bt = 0;
  55         int i;
  56         par[0] = 0;
  57         for (i = 0; i < len; i++) {
  58                 bt = data[i];
  59                 data[i] = crypto1_byte(pcs, 0x00, 0) ^ data[i];
  60                 if((i&0x0007) == 0) par[i>>3] = 0;
  61                 par[i>>3] |= (((filter(pcs->odd) ^ oddparity(bt)) & 0x01)<<(7-(i&0x0007)));
  62         }
  63         return;
  64 }
  65
  66 uint8_t mf_crypto1_encrypt4bit(struct Crypto1State *pcs, uint8_t data) {
  67         uint8_t bt = 0;
  68         int i;
  69
  70         for (i = 0; i < 4; i++)
  71                 bt |= (crypto1_bit(pcs, 0, 0) ^ BIT(data, i)) << i;
  72
  73         return bt;
  74 }
  75
  76 // send commands
  77 int mifare_sendcmd_short(struct Crypto1State *pcs, uint8_t crypted, uint8_t cmd, uint8_t data, uint8_t* answer, uint8_t *answer_parity, uint32_t *timing)
  78 {
  79         return mifare_sendcmd_shortex(pcs, crypted, cmd, data, answer, answer_parity, timing);
  80 }
  81
  82 int mifare_sendcmd_short_special(struct Crypto1State *pcs, uint8_t crypted, uint8_t cmd, uint8_t* data, uint8_t* answer, uint8_t *answer_parity, uint32_t *timing)
  83 {
  84     uint8_t dcmd[8];//, ecmd[4];
  85     //uint32_t par=0;
  86
  87     dcmd[0] = cmd;
  88     dcmd[1] = data[0];
  89         dcmd[2] = data[1];
  90         dcmd[3] = data[2];
  91         dcmd[4] = data[3];
  92         dcmd[5] = data[4];
  93         AppendCrc14443a(dcmd, 6);
  94         //Dbprintf("Data command: %02x", dcmd[0]);
  95         //Dbprintf("Data R: %02x %02x %02x %02x %02x %02x %02x", dcmd[1],dcmd[2],dcmd[3],dcmd[4],dcmd[5],dcmd[6],dcmd[7]);
  96
  97         //memcpy(ecmd, dcmd, sizeof(dcmd));
  98         ReaderTransmit(dcmd, sizeof(dcmd), NULL);
  99         int len = ReaderReceive(answer, answer_parity);
 100         if(!len)
 101         {
 102                 if (MF_DBGLEVEL >= 1)   Dbprintf("Authentication failed. Card timeout.");
 103                 return 2;
 104         }
 105         return len;
 106 }
 107
 108 int mifare_sendcmd_shortex(struct Crypto1State *pcs, uint8_t crypted, uint8_t cmd, uint8_t data, uint8_t *answer, uint8_t *answer_parity, uint32_t *timing)
 109 {
 110         uint8_t dcmd[4], ecmd[4];
 111         uint16_t pos, res;
 112         uint8_t par[1];                 // 1 Byte parity is enough here
 113         dcmd[0] = cmd;
 114         dcmd[1] = data;
 115         AppendCrc14443a(dcmd, 2);
 116
 117         memcpy(ecmd, dcmd, sizeof(dcmd));
 118
 119         if (crypted) {
 120                 par[0] = 0;
 121                 for (pos = 0; pos < 4; pos++)
 122                 {
 123                         ecmd[pos] = crypto1_byte(pcs, 0x00, 0) ^ dcmd[pos];
 124                         par[0] |= (((filter(pcs->odd) ^ oddparity(dcmd[pos])) & 0x01) << (7-pos));
 125                 }
 126
 127                 ReaderTransmitPar(ecmd, sizeof(ecmd), par, timing);
 128
 129         } else {
 130                 ReaderTransmit(dcmd, sizeof(dcmd), timing);
 131         }
 132
 133         int len = ReaderReceive(answer, par);
 134
 135         if (answer_parity) *answer_parity = par[0];
 136
 137         if (crypted == CRYPT_ALL) {
 138                 if (len == 1) {
 139                         res = 0;
 140                         for (pos = 0; pos < 4; pos++)
 141                                 res |= (crypto1_bit(pcs, 0, 0) ^ BIT(answer[0], pos)) << pos;
 142
 143                         answer[0] = res;
 144
 145                 } else {
 146                         for (pos = 0; pos < len; pos++)
 147                         {
 148                                 answer[pos] = crypto1_byte(pcs, 0x00, 0) ^ answer[pos];
 149                         }
 150                 }
 151         }
 152
 153         return len;
 154 }
 155
 156 // mifare commands
 157 int mifare_classic_auth(struct Crypto1State *pcs, uint32_t uid, uint8_t blockNo, uint8_t keyType, uint64_t ui64Key, uint8_t isNested)
 158 {
 159         return mifare_classic_authex(pcs, uid, blockNo, keyType, ui64Key, isNested, NULL, NULL);
 160 }
 161
 162 int mifare_classic_authex(struct Crypto1State *pcs, uint32_t uid, uint8_t blockNo, uint8_t keyType, uint64_t ui64Key, uint8_t isNested, uint32_t *ntptr, uint32_t *timing)
 163 {
 164         // variables
 165         int len;
 166         uint32_t pos;
 167         uint8_t tmp4[4];
 168         uint8_t par[1] = {0};
 169         byte_t nr[4];
 170         uint32_t nt, ntpp; // Supplied tag nonce
 171
 172         uint8_t mf_nr_ar[] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
 173         uint8_t *receivedAnswer = get_bigbufptr_recvrespbuf();
 174         uint8_t *receivedAnswerPar = receivedAnswer + MAX_FRAME_SIZE;
 175
 176         // Transmit MIFARE_CLASSIC_AUTH
 177         len = mifare_sendcmd_short(pcs, isNested, 0x60 + (keyType & 0x01), blockNo, receivedAnswer, receivedAnswerPar, timing);
 178         if (MF_DBGLEVEL >= 4)   Dbprintf("rand tag nonce len: %x", len);
 179         if (len != 4) return 1;
 180
 181         // "random" reader nonce:
 182         nr[0] = 0x55;
 183         nr[1] = 0x41;
 184         nr[2] = 0x49;
 185         nr[3] = 0x92;
 186
 187         // Save the tag nonce (nt)
 188         nt = bytes_to_num(receivedAnswer, 4);
 189
 190         //  ----------------------------- crypto1 create
 191         if (isNested)
 192                 crypto1_destroy(pcs);
 193
 194         // Init cipher with key
 195         crypto1_create(pcs, ui64Key);
 196
 197         if (isNested == AUTH_NESTED) {
 198                 // decrypt nt with help of new key
 199                 nt = crypto1_word(pcs, nt ^ uid, 1) ^ nt;
 200         } else {
 201                 // Load (plain) uid^nt into the cipher
 202                 crypto1_word(pcs, nt ^ uid, 0);
 203         }
 204
 205         // some statistic
 206         if (!ntptr && (MF_DBGLEVEL >= 3))
 207                 Dbprintf("auth uid: %08x nt: %08x", uid, nt);
 208
 209         // save Nt
 210         if (ntptr)
 211                 *ntptr = nt;
 212
 213
 214         // Generate (encrypted) nr+parity by loading it into the cipher (Nr)
 215         par[0] = 0;
 216         for (pos = 0; pos < 4; pos++)
 217         {
 218                 mf_nr_ar[pos] = crypto1_byte(pcs, nr[pos], 0) ^ nr[pos];
 219                 par[0] |= (((filter(pcs->odd) ^ oddparity(nr[pos])) & 0x01) << (7-pos));
 220         }
 221
 222         // Skip 32 bits in pseudo random generator
 223         nt = prng_successor(nt,32);
 224
 225         //  ar+parity
 226         for (pos = 4; pos < 8; pos++)
 227         {
 228                 nt = prng_successor(nt,8);
 229                 mf_nr_ar[pos] = crypto1_byte(pcs,0x00,0) ^ (nt & 0xff);
 230                 par[0] |= (((filter(pcs->odd) ^ oddparity(nt & 0xff)) & 0x01) << (7-pos));
 231         }
 232
 233         // Transmit reader nonce and reader answer
 234         ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar), par, NULL);
 235
 236         // Receive 4 byte tag answer
 237         len = ReaderReceive(receivedAnswer, receivedAnswerPar);
 238         if (!len)
 239         {
 240                 if (MF_DBGLEVEL >= 1)   Dbprintf("Authentication failed. Card timeout.");
 241                 return 2;
 242         }
 243
 244         memcpy(tmp4, receivedAnswer, 4);
 245         ntpp = prng_successor(nt, 32) ^ crypto1_word(pcs, 0,0);
 246
 247         if (ntpp != bytes_to_num(tmp4, 4)) {
 248                 if (MF_DBGLEVEL >= 1)   Dbprintf("Authentication failed. Error card response.");
 249                 return 3;
 250         }
 251
 252         return 0;
 253 }
 254
 255 int mifare_classic_readblock(struct Crypto1State *pcs, uint32_t uid, uint8_t blockNo, uint8_t *blockData)
 256 {
 257         // variables
 258         int len;
 259         uint8_t bt[2];
 260
 261         uint8_t* receivedAnswer = get_bigbufptr_recvrespbuf();
 262         uint8_t* receivedAnswerPar = receivedAnswer + MAX_FRAME_SIZE;
 263
 264         // command MIFARE_CLASSIC_READBLOCK
 265         len = mifare_sendcmd_short(pcs, 1, 0x30, blockNo, receivedAnswer, receivedAnswerPar, NULL);
 266         if (len == 1) {
 267                 if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd Error: %02x", receivedAnswer[0]);
 268                 return 1;
 269         }
 270         if (len != 18) {
 271                 if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd Error: card timeout. len: %x", len);
 272                 return 2;
 273         }
 274
 275         memcpy(bt, receivedAnswer + 16, 2);
 276         AppendCrc14443a(receivedAnswer, 16);
 277         if (bt[0] != receivedAnswer[16] || bt[1] != receivedAnswer[17]) {
 278                 if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd CRC response error.");
 279                 return 3;
 280         }
 281
 282         memcpy(blockData, receivedAnswer, 16);
 283         return 0;
 284 }
 285
 286 int mifare_ultra_readblock(uint32_t uid, uint8_t blockNo, uint8_t *blockData)
 287 {
 288         // variables
 289         uint16_t len;
 290         uint8_t bt[2];
 291
 292         uint8_t* receivedAnswer = get_bigbufptr_recvrespbuf();
 293         uint8_t* receivedAnswerPar = receivedAnswer + MAX_FRAME_SIZE;
 294
 295         // command MIFARE_CLASSIC_READBLOCK
 296         len = mifare_sendcmd_short(NULL, 1, 0x30, blockNo, receivedAnswer, receivedAnswerPar, NULL);
 297         if (len == 1) {
 298                 if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd Error: %02x", receivedAnswer[0]);
 299                 return 1;
 300         }
 301         if (len != 18) {
 302                 if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd Error: card timeout. len: %x", len);
 303                 return 2;
 304         }
 305
 306         memcpy(bt, receivedAnswer + 16, 2);
 307         AppendCrc14443a(receivedAnswer, 16);
 308         if (bt[0] != receivedAnswer[16] || bt[1] != receivedAnswer[17]) {
 309                 if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd CRC response error.");
 310                 return 3;
 311         }
 312
 313         memcpy(blockData, receivedAnswer, 14);
 314         return 0;
 315 }
 316
 317
 318 int mifare_classic_writeblock(struct Crypto1State *pcs, uint32_t uid, uint8_t blockNo, uint8_t *blockData)
 319 {
 320         // variables
 321         int len, i;
 322         uint32_t pos;
 323         uint8_t par[3] = {0};           // enough for 18 Bytes to send
 324         byte_t res;
 325
 326         uint8_t d_block[18], d_block_enc[18];
 327         uint8_t* receivedAnswer = get_bigbufptr_recvrespbuf();
 328         uint8_t* receivedAnswerPar = receivedAnswer + MAX_FRAME_SIZE;
 329
 330         // command MIFARE_CLASSIC_WRITEBLOCK
 331         len = mifare_sendcmd_short(pcs, 1, 0xA0, blockNo, receivedAnswer, receivedAnswerPar, NULL);
 332
 333         if ((len != 1) || (receivedAnswer[0] != 0x0A)) {   //  0x0a - ACK
 334                 if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd Error: %02x", receivedAnswer[0]);
 335                 return 1;
 336         }
 337
 338         memcpy(d_block, blockData, 16);
 339         AppendCrc14443a(d_block, 16);
 340
 341         // crypto
 342         for (pos = 0; pos < 18; pos++)
 343         {
 344                 d_block_enc[pos] = crypto1_byte(pcs, 0x00, 0) ^ d_block[pos];
 345                 par[pos>>3] |= (((filter(pcs->odd) ^ oddparity(d_block[pos])) & 0x01) << (7 - (pos&0x0007)));
 346         }
 347
 348         ReaderTransmitPar(d_block_enc, sizeof(d_block_enc), par, NULL);
 349
 350         // Receive the response
 351         len = ReaderReceive(receivedAnswer, receivedAnswerPar);
 352
 353         res = 0;
 354         for (i = 0; i < 4; i++)
 355                 res |= (crypto1_bit(pcs, 0, 0) ^ BIT(receivedAnswer[0], i)) << i;
 356
 357         if ((len != 1) || (res != 0x0A)) {
 358                 if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd send data2 Error: %02x", res);
 359                 return 2;
 360         }
 361
 362         return 0;
 363 }
 364
 365 int mifare_ultra_writeblock(uint32_t uid, uint8_t blockNo, uint8_t *blockData)
 366 {
 367     // variables
 368     uint16_t len;
 369     uint8_t par[3] = {0};  // enough for 18 parity bits
 370
 371     uint8_t d_block[18];
 372     uint8_t* receivedAnswer = get_bigbufptr_recvrespbuf();
 373         uint8_t* receivedAnswerPar = receivedAnswer + MAX_FRAME_SIZE;
 374
 375     // command MIFARE_CLASSIC_WRITEBLOCK
 376     len = mifare_sendcmd_short(NULL, true, 0xA0, blockNo, receivedAnswer, receivedAnswerPar, NULL);
 377
 378     if ((len != 1) || (receivedAnswer[0] != 0x0A)) {   //  0x0a - ACK
 379         if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd Addr Error: %02x", receivedAnswer[0]);
 380         return 1;
 381     }
 382
 383         memset(d_block,'\0',18);
 384         memcpy(d_block, blockData, 16);
 385     AppendCrc14443a(d_block, 16);
 386
 387         ReaderTransmitPar(d_block, sizeof(d_block), par, NULL);
 388
 389     // Receive the response
 390     len = ReaderReceive(receivedAnswer, receivedAnswerPar);
 391
 392         if ((len != 1) || (receivedAnswer[0] != 0x0A)) {   //  0x0a - ACK
 393         if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd Data Error: %02x %d", receivedAnswer[0],len);
 394         return 2;
 395     }
 396
 397     return 0;
 398 }
 399
 400 int mifare_ultra_special_writeblock(uint32_t uid, uint8_t blockNo, uint8_t *blockData)
 401 {
 402     uint16_t len;
 403
 404     uint8_t d_block[8];
 405     uint8_t *receivedAnswer = get_bigbufptr_recvrespbuf();
 406         uint8_t *receivedAnswerPar = receivedAnswer + MAX_FRAME_SIZE;
 407
 408     // command MIFARE_CLASSIC_WRITEBLOCK
 409         memset(d_block,'\0',8);
 410         d_block[0]= blockNo;
 411         memcpy(d_block+1,blockData,4);
 412         AppendCrc14443a(d_block, 6);
 413
 414         //i know the data send here is correct
 415     len = mifare_sendcmd_short_special(NULL, 1, 0xA2, d_block, receivedAnswer, receivedAnswerPar, NULL);
 416
 417     if (receivedAnswer[0] != 0x0A) {   //  0x0a - ACK
 418         if (MF_DBGLEVEL >= 1)   Dbprintf("Cmd Send Error: %02x %d", receivedAnswer[0],len);
 419         return 1;
 420     }
 421
 422     return 0;
 423 }
 424
 425 int mifare_classic_halt(struct Crypto1State *pcs, uint32_t uid)
 426 {
 427         // variables
 428         uint16_t len;
 429
 430         // Mifare HALT
 431         uint8_t *receivedAnswer = get_bigbufptr_recvrespbuf();
 432         uint8_t *receivedAnswerPar = receivedAnswer + MAX_FRAME_SIZE;
 433
 434         len = mifare_sendcmd_short(pcs, pcs == NULL ? false:true, 0x50, 0x00, receivedAnswer, receivedAnswerPar, NULL);
 435         if (len != 0) {
 436                 if (MF_DBGLEVEL >= 1)   Dbprintf("halt error. response len: %x", len);
 437                 return 1;
 438         }
 439
 440         return 0;
 441 }
 442
 443 int mifare_ultra_halt(uint32_t uid)
 444 {
 445         uint16_t len;
 446
 447         // Mifare HALT
 448         uint8_t *receivedAnswer = get_bigbufptr_recvrespbuf();
 449         uint8_t *receivedAnswerPar = receivedAnswer + MAX_FRAME_SIZE;
 450
 451         len = mifare_sendcmd_short(NULL, true, 0x50, 0x00, receivedAnswer, receivedAnswerPar, NULL);
 452         if (len != 0) {
 453                 if (MF_DBGLEVEL >= 1)   Dbprintf("halt error. response len: %x", len);
 454                 return 1;
 455         }
 456
 457         return 0;
 458 }
 459
 460
 461 // Mifare Memory Structure: up to 32 Sectors with 4 blocks each (1k and 2k cards),
 462 // plus evtl. 8 sectors with 16 blocks each (4k cards)
 463 uint8_t NumBlocksPerSector(uint8_t sectorNo)
 464 {
 465         if (sectorNo < 32)
 466                 return 4;
 467         else
 468                 return 16;
 469 }
 470
 471 uint8_t FirstBlockOfSector(uint8_t sectorNo)
 472 {
 473         if (sectorNo < 32)
 474                 return sectorNo * 4;
 475         else
 476                 return 32*4 + (sectorNo - 32) * 16;
 477
 478 }
 479
 480
 481 // work with emulator memory
 482 void emlSetMem(uint8_t *data, int blockNum, int blocksCount) {
 483         uint8_t* emCARD = get_bigbufptr_emlcardmem();
 484
 485         memcpy(emCARD + blockNum * 16, data, blocksCount * 16);
 486 }
 487
 488 void emlGetMem(uint8_t *data, int blockNum, int blocksCount) {
 489         uint8_t* emCARD = get_bigbufptr_emlcardmem();
 490
 491         memcpy(data, emCARD + blockNum * 16, blocksCount * 16);
 492 }
 493
 494 void emlGetMemBt(uint8_t *data, int bytePtr, int byteCount) {
 495         uint8_t* emCARD = get_bigbufptr_emlcardmem();
 496
 497         memcpy(data, emCARD + bytePtr, byteCount);
 498 }
 499
 500 int emlCheckValBl(int blockNum) {
 501         uint8_t* emCARD = get_bigbufptr_emlcardmem();
 502         uint8_t* data = emCARD + blockNum * 16;
 503
 504         if ((data[0] != (data[4] ^ 0xff)) || (data[0] != data[8]) ||
 505                         (data[1] != (data[5] ^ 0xff)) || (data[1] != data[9]) ||
 506                         (data[2] != (data[6] ^ 0xff)) || (data[2] != data[10]) ||
 507                         (data[3] != (data[7] ^ 0xff)) || (data[3] != data[11]) ||
 508                         (data[12] != (data[13] ^ 0xff)) || (data[12] != data[14]) ||
 509                         (data[12] != (data[15] ^ 0xff))
 510                  )
 511                 return 1;
 512         return 0;
 513 }
 514
 515 int emlGetValBl(uint32_t *blReg, uint8_t *blBlock, int blockNum) {
 516         uint8_t* emCARD = get_bigbufptr_emlcardmem();
 517         uint8_t* data = emCARD + blockNum * 16;
 518
 519         if (emlCheckValBl(blockNum)) {
 520                 return 1;
 521         }
 522
 523         memcpy(blReg, data, 4);
 524         *blBlock = data[12];
 525
 526         return 0;
 527 }
 528
 529 int emlSetValBl(uint32_t blReg, uint8_t blBlock, int blockNum) {
 530         uint8_t* emCARD = get_bigbufptr_emlcardmem();
 531         uint8_t* data = emCARD + blockNum * 16;
 532
 533         memcpy(data + 0, &blReg, 4);
 534         memcpy(data + 8, &blReg, 4);
 535         blReg = blReg ^ 0xffffffff;
 536         memcpy(data + 4, &blReg, 4);
 537
 538         data[12] = blBlock;
 539         data[13] = blBlock ^ 0xff;
 540         data[14] = blBlock;
 541         data[15] = blBlock ^ 0xff;
 542
 543         return 0;
 544 }
 545
 546 uint64_t emlGetKey(int sectorNum, int keyType) {
 547         uint8_t key[6];
 548         uint8_t* emCARD = get_bigbufptr_emlcardmem();
 549
 550         memcpy(key, emCARD + 16 * (FirstBlockOfSector(sectorNum) + NumBlocksPerSector(sectorNum) - 1) + keyType * 10, 6);
 551         return bytes_to_num(key, 6);
 552 }
 553
 554 void emlClearMem(void) {
 555         int b;
 556
 557         const uint8_t trailer[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x07, 0x80, 0x69, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 558         const uint8_t uid[]   =   {0xe6, 0x84, 0x87, 0xf3, 0x16, 0x88, 0x04, 0x00, 0x46, 0x8e, 0x45, 0x55, 0x4d, 0x70, 0x41, 0x04};
 559         uint8_t* emCARD = get_bigbufptr_emlcardmem();
 560
 561         memset(emCARD, 0, CARD_MEMORY_SIZE);
 562
 563         // fill sectors trailer data
 564         for(b = 3; b < 256; b<127?(b+=4):(b+=16)) {
 565                 emlSetMem((uint8_t *)trailer, b , 1);
 566         }
 567
 568         // uid
 569         emlSetMem((uint8_t *)uid, 0, 1);
 570         return;
 571 }