armsrc/iclass.c

   1 //-----------------------------------------------------------------------------
   2 // Gerhard de Koning Gans - May 2008
   3 // Hagen Fritsch - June 2010
   4 // Gerhard de Koning Gans - May 2011
   5 // Gerhard de Koning Gans - June 2012 - Added iClass card and reader emulation
   6 //
   7 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   8 // at your option, any later version. See the LICENSE.txt file for the text of
   9 // the license.
  10 //-----------------------------------------------------------------------------
  11 // Routines to support iClass.
  12 //-----------------------------------------------------------------------------
  13 // Based on ISO14443a implementation. Still in experimental phase.
  14 // Contribution made during a security research at Radboud University Nijmegen
  15 //
  16 // Please feel free to contribute and extend iClass support!!
  17 //-----------------------------------------------------------------------------
  18 //
  19 // FIX:
  20 // ====
  21 // We still have sometimes a demodulation error when snooping iClass communication.
  22 // The resulting trace of a read-block-03 command may look something like this:
  23 //
  24 //  +  22279:    :     0c  03  e8  01
  25 //
  26 //    ...with an incorrect answer...
  27 //
  28 //  +     85:   0: TAG ff! ff! ff! ff! ff! ff! ff! ff! bb  33  bb  00  01! 0e! 04! bb     !crc
  29 //
  30 // We still left the error signalling bytes in the traces like 0xbb
  31 //
  32 // A correct trace should look like this:
  33 //
  34 // +  21112:    :     0c  03  e8  01
  35 // +     85:   0: TAG ff  ff  ff  ff  ff  ff  ff  ff  ea  f5
  36 //
  37 //-----------------------------------------------------------------------------
  38
  39 #include "proxmark3.h"
  40 #include "apps.h"
  41 #include "util.h"
  42 #include "string.h"
  43 #include "common.h"
  44 #include "cmd.h"
  45 // Needed for CRC in emulation mode;
  46 // same construction as in ISO 14443;
  47 // different initial value (CRC_ICLASS)
  48 #include "iso14443crc.h"
  49 #include "iso15693tools.h"
  50 #include "cipher.h"
  51 #include "protocols.h"
  52 static int timeout = 4096;
  53
  54
  55 static int SendIClassAnswer(uint8_t *resp, int respLen, int delay);
  56
  57 //-----------------------------------------------------------------------------
  58 // The software UART that receives commands from the reader, and its state
  59 // variables.
  60 //-----------------------------------------------------------------------------
  61 static struct {
  62     enum {
  63         STATE_UNSYNCD,
  64         STATE_START_OF_COMMUNICATION,
  65         STATE_RECEIVING
  66     }       state;
  67     uint16_t    shiftReg;
  68     int     bitCnt;
  69     int     byteCnt;
  70     int     byteCntMax;
  71     int     posCnt;
  72     int     nOutOfCnt;
  73     int     OutOfCnt;
  74     int     syncBit;
  75     int     samples;
  76     int     highCnt;
  77     int     swapper;
  78     int     counter;
  79     int     bitBuffer;
  80     int     dropPosition;
  81     uint8_t *output;
  82 } Uart;
  83
  84 static RAMFUNC int OutOfNDecoding(int bit)
  85 {
  86         //int error = 0;
  87         int bitright;
  88
  89         if(!Uart.bitBuffer) {
  90                 Uart.bitBuffer = bit ^ 0xFF0;
  91                 return FALSE;
  92         }
  93         else {
  94                 Uart.bitBuffer <<= 4;
  95                 Uart.bitBuffer ^= bit;
  96         }
  97
  98         /*if(Uart.swapper) {
  99                 Uart.output[Uart.byteCnt] = Uart.bitBuffer & 0xFF;
 100                 Uart.byteCnt++;
 101                 Uart.swapper = 0;
 102                 if(Uart.byteCnt > 15) { return TRUE; }
 103         }
 104         else {
 105                 Uart.swapper = 1;
 106         }*/
 107
 108         if(Uart.state != STATE_UNSYNCD) {
 109                 Uart.posCnt++;
 110
 111                 if((Uart.bitBuffer & Uart.syncBit) ^ Uart.syncBit) {
 112                         bit = 0x00;
 113                 }
 114                 else {
 115                         bit = 0x01;
 116                 }
 117                 if(((Uart.bitBuffer << 1) & Uart.syncBit) ^ Uart.syncBit) {
 118                         bitright = 0x00;
 119                 }
 120                 else {
 121                         bitright = 0x01;
 122                 }
 123                 if(bit != bitright) { bit = bitright; }
 124
 125
 126                 // So, now we only have to deal with *bit*, lets see...
 127                 if(Uart.posCnt == 1) {
 128                         // measurement first half bitperiod
 129                         if(!bit) {
 130                                 // Drop in first half means that we are either seeing
 131                                 // an SOF or an EOF.
 132
 133                                 if(Uart.nOutOfCnt == 1) {
 134                                         // End of Communication
 135                                         Uart.state = STATE_UNSYNCD;
 136                                         Uart.highCnt = 0;
 137                                         if(Uart.byteCnt == 0) {
 138                                                 // Its not straightforward to show single EOFs
 139                                                 // So just leave it and do not return TRUE
 140                                                 Uart.output[0] = 0xf0;
 141                                                 Uart.byteCnt++;
 142                                         }
 143                                         else {
 144                                                 return TRUE;
 145                                         }
 146                                 }
 147                                 else if(Uart.state != STATE_START_OF_COMMUNICATION) {
 148                                         // When not part of SOF or EOF, it is an error
 149                                         Uart.state = STATE_UNSYNCD;
 150                                         Uart.highCnt = 0;
 151                                         //error = 4;
 152                                 }
 153                         }
 154                 }
 155                 else {
 156                         // measurement second half bitperiod
 157                         // Count the bitslot we are in... (ISO 15693)
 158                         Uart.nOutOfCnt++;
 159
 160                         if(!bit) {
 161                                 if(Uart.dropPosition) {
 162                                         if(Uart.state == STATE_START_OF_COMMUNICATION) {
 163                                                 //error = 1;
 164                                         }
 165                                         else {
 166                                                 //error = 7;
 167                                         }
 168                                         // It is an error if we already have seen a drop in current frame
 169                                         Uart.state = STATE_UNSYNCD;
 170                                         Uart.highCnt = 0;
 171                                 }
 172                                 else {
 173                                         Uart.dropPosition = Uart.nOutOfCnt;
 174                                 }
 175                         }
 176
 177                         Uart.posCnt = 0;
 178
 179
 180                         if(Uart.nOutOfCnt == Uart.OutOfCnt && Uart.OutOfCnt == 4) {
 181                                 Uart.nOutOfCnt = 0;
 182
 183                                 if(Uart.state == STATE_START_OF_COMMUNICATION) {
 184                                         if(Uart.dropPosition == 4) {
 185                                                 Uart.state = STATE_RECEIVING;
 186                                                 Uart.OutOfCnt = 256;
 187                                         }
 188                                         else if(Uart.dropPosition == 3) {
 189                                                 Uart.state = STATE_RECEIVING;
 190                                                 Uart.OutOfCnt = 4;
 191                                                 //Uart.output[Uart.byteCnt] = 0xdd;
 192                                                 //Uart.byteCnt++;
 193                                         }
 194                                         else {
 195                                                 Uart.state = STATE_UNSYNCD;
 196                                                 Uart.highCnt = 0;
 197                                         }
 198                                         Uart.dropPosition = 0;
 199                                 }
 200                                 else {
 201                                         // RECEIVING DATA
 202                                         // 1 out of 4
 203                                         if(!Uart.dropPosition) {
 204                                                 Uart.state = STATE_UNSYNCD;
 205                                                 Uart.highCnt = 0;
 206                                                 //error = 9;
 207                                         }
 208                                         else {
 209                                                 Uart.shiftReg >>= 2;
 210
 211                                                 // Swap bit order
 212                                                 Uart.dropPosition--;
 213                                                 //if(Uart.dropPosition == 1) { Uart.dropPosition = 2; }
 214                                                 //else if(Uart.dropPosition == 2) { Uart.dropPosition = 1; }
 215
 216                                                 Uart.shiftReg ^= ((Uart.dropPosition & 0x03) << 6);
 217                                                 Uart.bitCnt += 2;
 218                                                 Uart.dropPosition = 0;
 219
 220                                                 if(Uart.bitCnt == 8) {
 221                                                         Uart.output[Uart.byteCnt] = (Uart.shiftReg & 0xff);
 222                                                         Uart.byteCnt++;
 223                                                         Uart.bitCnt = 0;
 224                                                         Uart.shiftReg = 0;
 225                                                 }
 226                                         }
 227                                 }
 228                         }
 229                         else if(Uart.nOutOfCnt == Uart.OutOfCnt) {
 230                                 // RECEIVING DATA
 231                                 // 1 out of 256
 232                                 if(!Uart.dropPosition) {
 233                                         Uart.state = STATE_UNSYNCD;
 234                                         Uart.highCnt = 0;
 235                                         //error = 3;
 236                                 }
 237                                 else {
 238                                         Uart.dropPosition--;
 239                                         Uart.output[Uart.byteCnt] = (Uart.dropPosition & 0xff);
 240                                         Uart.byteCnt++;
 241                                         Uart.bitCnt = 0;
 242                                         Uart.shiftReg = 0;
 243                                         Uart.nOutOfCnt = 0;
 244                                         Uart.dropPosition = 0;
 245                                 }
 246                         }
 247
 248                         /*if(error) {
 249                                 Uart.output[Uart.byteCnt] = 0xAA;
 250                                 Uart.byteCnt++;
 251                                 Uart.output[Uart.byteCnt] = error & 0xFF;
 252                                 Uart.byteCnt++;
 253                                 Uart.output[Uart.byteCnt] = 0xAA;
 254                                 Uart.byteCnt++;
 255                                 Uart.output[Uart.byteCnt] = (Uart.bitBuffer >> 8) & 0xFF;
 256                                 Uart.byteCnt++;
 257                                 Uart.output[Uart.byteCnt] = Uart.bitBuffer & 0xFF;
 258                                 Uart.byteCnt++;
 259                                 Uart.output[Uart.byteCnt] = (Uart.syncBit >> 3) & 0xFF;
 260                                 Uart.byteCnt++;
 261                                 Uart.output[Uart.byteCnt] = 0xAA;
 262                                 Uart.byteCnt++;
 263                                 return TRUE;
 264                         }*/
 265                 }
 266
 267         }
 268         else {
 269                 bit = Uart.bitBuffer & 0xf0;
 270                 bit >>= 4;
 271                 bit ^= 0x0F; // drops become 1s ;-)
 272                 if(bit) {
 273                         // should have been high or at least (4 * 128) / fc
 274                         // according to ISO this should be at least (9 * 128 + 20) / fc
 275                         if(Uart.highCnt == 8) {
 276                                 // we went low, so this could be start of communication
 277                                 // it turns out to be safer to choose a less significant
 278                                 // syncbit... so we check whether the neighbour also represents the drop
 279                                 Uart.posCnt = 1;   // apparently we are busy with our first half bit period
 280                                 Uart.syncBit = bit & 8;
 281                                 Uart.samples = 3;
 282                                 if(!Uart.syncBit)       { Uart.syncBit = bit & 4; Uart.samples = 2; }
 283                                 else if(bit & 4)        { Uart.syncBit = bit & 4; Uart.samples = 2; bit <<= 2; }
 284                                 if(!Uart.syncBit)       { Uart.syncBit = bit & 2; Uart.samples = 1; }
 285                                 else if(bit & 2)        { Uart.syncBit = bit & 2; Uart.samples = 1; bit <<= 1; }
 286                                 if(!Uart.syncBit)       { Uart.syncBit = bit & 1; Uart.samples = 0;
 287                                         if(Uart.syncBit && (Uart.bitBuffer & 8)) {
 288                                                 Uart.syncBit = 8;
 289
 290                                                 // the first half bit period is expected in next sample
 291                                                 Uart.posCnt = 0;
 292                                                 Uart.samples = 3;
 293                                         }
 294                                 }
 295                                 else if(bit & 1)        { Uart.syncBit = bit & 1; Uart.samples = 0; }
 296
 297                                 Uart.syncBit <<= 4;
 298                                 Uart.state = STATE_START_OF_COMMUNICATION;
 299                                 Uart.bitCnt = 0;
 300                                 Uart.byteCnt = 0;
 301                                 Uart.nOutOfCnt = 0;
 302                                 Uart.OutOfCnt = 4; // Start at 1/4, could switch to 1/256
 303                                 Uart.dropPosition = 0;
 304                                 Uart.shiftReg = 0;
 305                                 //error = 0;
 306                         }
 307                         else {
 308                                 Uart.highCnt = 0;
 309                         }
 310                 }
 311                 else {
 312                         if(Uart.highCnt < 8) {
 313                                 Uart.highCnt++;
 314                         }
 315                 }
 316         }
 317
 318     return FALSE;
 319 }
 320
 321 //=============================================================================
 322 // Manchester
 323 //=============================================================================
 324
 325 static struct {
 326     enum {
 327         DEMOD_UNSYNCD,
 328                 DEMOD_START_OF_COMMUNICATION,
 329                 DEMOD_START_OF_COMMUNICATION2,
 330                 DEMOD_START_OF_COMMUNICATION3,
 331                 DEMOD_SOF_COMPLETE,
 332                 DEMOD_MANCHESTER_D,
 333                 DEMOD_MANCHESTER_E,
 334                 DEMOD_END_OF_COMMUNICATION,
 335                 DEMOD_END_OF_COMMUNICATION2,
 336                 DEMOD_MANCHESTER_F,
 337         DEMOD_ERROR_WAIT
 338     }       state;
 339     int     bitCount;
 340     int     posCount;
 341         int     syncBit;
 342     uint16_t    shiftReg;
 343         int     buffer;
 344         int     buffer2;
 345         int     buffer3;
 346         int     buff;
 347         int     samples;
 348     int     len;
 349         enum {
 350                 SUB_NONE,
 351                 SUB_FIRST_HALF,
 352                 SUB_SECOND_HALF,
 353                 SUB_BOTH
 354         }               sub;
 355     uint8_t *output;
 356 } Demod;
 357
 358 static RAMFUNC int ManchesterDecoding(int v)
 359 {
 360         int bit;
 361         int modulation;
 362         int error = 0;
 363
 364         bit = Demod.buffer;
 365         Demod.buffer = Demod.buffer2;
 366         Demod.buffer2 = Demod.buffer3;
 367         Demod.buffer3 = v;
 368
 369         if(Demod.buff < 3) {
 370                 Demod.buff++;
 371                 return FALSE;
 372         }
 373
 374         if(Demod.state==DEMOD_UNSYNCD) {
 375                 Demod.output[Demod.len] = 0xfa;
 376                 Demod.syncBit = 0;
 377                 //Demod.samples = 0;
 378                 Demod.posCount = 1;             // This is the first half bit period, so after syncing handle the second part
 379
 380                 if(bit & 0x08) {
 381                         Demod.syncBit = 0x08;
 382                 }
 383
 384                 if(bit & 0x04) {
 385                         if(Demod.syncBit) {
 386                                 bit <<= 4;
 387                         }
 388                         Demod.syncBit = 0x04;
 389                 }
 390
 391                 if(bit & 0x02) {
 392                         if(Demod.syncBit) {
 393                                 bit <<= 2;
 394                         }
 395                         Demod.syncBit = 0x02;
 396                 }
 397
 398                 if(bit & 0x01 && Demod.syncBit) {
 399                         Demod.syncBit = 0x01;
 400                 }
 401
 402                 if(Demod.syncBit) {
 403                         Demod.len = 0;
 404                         Demod.state = DEMOD_START_OF_COMMUNICATION;
 405                         Demod.sub = SUB_FIRST_HALF;
 406                         Demod.bitCount = 0;
 407                         Demod.shiftReg = 0;
 408                         Demod.samples = 0;
 409                         if(Demod.posCount) {
 410                                 //if(trigger) LED_A_OFF();  // Not useful in this case...
 411                                 switch(Demod.syncBit) {
 412                                         case 0x08: Demod.samples = 3; break;
 413                                         case 0x04: Demod.samples = 2; break;
 414                                         case 0x02: Demod.samples = 1; break;
 415                                         case 0x01: Demod.samples = 0; break;
 416                                 }
 417                                 // SOF must be long burst... otherwise stay unsynced!!!
 418                                 if(!(Demod.buffer & Demod.syncBit) || !(Demod.buffer2 & Demod.syncBit)) {
 419                                         Demod.state = DEMOD_UNSYNCD;
 420                                 }
 421                         }
 422                         else {
 423                                 // SOF must be long burst... otherwise stay unsynced!!!
 424                                 if(!(Demod.buffer2 & Demod.syncBit) || !(Demod.buffer3 & Demod.syncBit)) {
 425                                         Demod.state = DEMOD_UNSYNCD;
 426                                         error = 0x88;
 427                                 }
 428
 429                         }
 430                         error = 0;
 431
 432                 }
 433         }
 434         else {
 435                 modulation = bit & Demod.syncBit;
 436                 modulation |= ((bit << 1) ^ ((Demod.buffer & 0x08) >> 3)) & Demod.syncBit;
 437
 438                 Demod.samples += 4;
 439
 440                 if(Demod.posCount==0) {
 441                         Demod.posCount = 1;
 442                         if(modulation) {
 443                                 Demod.sub = SUB_FIRST_HALF;
 444                         }
 445                         else {
 446                                 Demod.sub = SUB_NONE;
 447                         }
 448                 }
 449                 else {
 450                         Demod.posCount = 0;
 451                         /*(modulation && (Demod.sub == SUB_FIRST_HALF)) {
 452                                 if(Demod.state!=DEMOD_ERROR_WAIT) {
 453                                         Demod.state = DEMOD_ERROR_WAIT;
 454                                         Demod.output[Demod.len] = 0xaa;
 455                                         error = 0x01;
 456                                 }
 457                         }*/
 458                         //else if(modulation) {
 459                         if(modulation) {
 460                                 if(Demod.sub == SUB_FIRST_HALF) {
 461                                         Demod.sub = SUB_BOTH;
 462                                 }
 463                                 else {
 464                                         Demod.sub = SUB_SECOND_HALF;
 465                                 }
 466                         }
 467                         else if(Demod.sub == SUB_NONE) {
 468                                 if(Demod.state == DEMOD_SOF_COMPLETE) {
 469                                         Demod.output[Demod.len] = 0x0f;
 470                                         Demod.len++;
 471                                         Demod.state = DEMOD_UNSYNCD;
 472 //                                      error = 0x0f;
 473                                         return TRUE;
 474                                 }
 475                                 else {
 476                                         Demod.state = DEMOD_ERROR_WAIT;
 477                                         error = 0x33;
 478                                 }
 479                                 /*if(Demod.state!=DEMOD_ERROR_WAIT) {
 480                                         Demod.state = DEMOD_ERROR_WAIT;
 481                                         Demod.output[Demod.len] = 0xaa;
 482                                         error = 0x01;
 483                                 }*/
 484                         }
 485
 486                         switch(Demod.state) {
 487                                 case DEMOD_START_OF_COMMUNICATION:
 488                                         if(Demod.sub == SUB_BOTH) {
 489                                                 //Demod.state = DEMOD_MANCHESTER_D;
 490                                                 Demod.state = DEMOD_START_OF_COMMUNICATION2;
 491                                                 Demod.posCount = 1;
 492                                                 Demod.sub = SUB_NONE;
 493                                         }
 494                                         else {
 495                                                 Demod.output[Demod.len] = 0xab;
 496                                                 Demod.state = DEMOD_ERROR_WAIT;
 497                                                 error = 0xd2;
 498                                         }
 499                                         break;
 500                                 case DEMOD_START_OF_COMMUNICATION2:
 501                                         if(Demod.sub == SUB_SECOND_HALF) {
 502                                                 Demod.state = DEMOD_START_OF_COMMUNICATION3;
 503                                         }
 504                                         else {
 505                                                 Demod.output[Demod.len] = 0xab;
 506                                                 Demod.state = DEMOD_ERROR_WAIT;
 507                                                 error = 0xd3;
 508                                         }
 509                                         break;
 510                                 case DEMOD_START_OF_COMMUNICATION3:
 511                                         if(Demod.sub == SUB_SECOND_HALF) {
 512 //                                              Demod.state = DEMOD_MANCHESTER_D;
 513                                                 Demod.state = DEMOD_SOF_COMPLETE;
 514                                                 //Demod.output[Demod.len] = Demod.syncBit & 0xFF;
 515                                                 //Demod.len++;
 516                                         }
 517                                         else {
 518                                                 Demod.output[Demod.len] = 0xab;
 519                                                 Demod.state = DEMOD_ERROR_WAIT;
 520                                                 error = 0xd4;
 521                                         }
 522                                         break;
 523                                 case DEMOD_SOF_COMPLETE:
 524                                 case DEMOD_MANCHESTER_D:
 525                                 case DEMOD_MANCHESTER_E:
 526                                         // OPPOSITE FROM ISO14443 - 11110000 = 0 (1 in 14443)
 527                                         //                          00001111 = 1 (0 in 14443)
 528                                         if(Demod.sub == SUB_SECOND_HALF) { // SUB_FIRST_HALF
 529                                                 Demod.bitCount++;
 530                                                 Demod.shiftReg = (Demod.shiftReg >> 1) ^ 0x100;
 531                                                 Demod.state = DEMOD_MANCHESTER_D;
 532                                         }
 533                                         else if(Demod.sub == SUB_FIRST_HALF) { // SUB_SECOND_HALF
 534                                                 Demod.bitCount++;
 535                                                 Demod.shiftReg >>= 1;
 536                                                 Demod.state = DEMOD_MANCHESTER_E;
 537                                         }
 538                                         else if(Demod.sub == SUB_BOTH) {
 539                                                 Demod.state = DEMOD_MANCHESTER_F;
 540                                         }
 541                                         else {
 542                                                 Demod.state = DEMOD_ERROR_WAIT;
 543                                                 error = 0x55;
 544                                         }
 545                                         break;
 546
 547                                 case DEMOD_MANCHESTER_F:
 548                                         // Tag response does not need to be a complete byte!
 549                                         if(Demod.len > 0 || Demod.bitCount > 0) {
 550                                                 if(Demod.bitCount > 1) {  // was > 0, do not interpret last closing bit, is part of EOF
 551                                                         Demod.shiftReg >>= (9 - Demod.bitCount);        // right align data
 552                                                         Demod.output[Demod.len] = Demod.shiftReg & 0xff;
 553                                                         Demod.len++;
 554                                                 }
 555
 556                                                 Demod.state = DEMOD_UNSYNCD;
 557                                                 return TRUE;
 558                                         }
 559                                         else {
 560                                                 Demod.output[Demod.len] = 0xad;
 561                                                 Demod.state = DEMOD_ERROR_WAIT;
 562                                                 error = 0x03;
 563                                         }
 564                                         break;
 565
 566                                 case DEMOD_ERROR_WAIT:
 567                                         Demod.state = DEMOD_UNSYNCD;
 568                                         break;
 569
 570                                 default:
 571                                         Demod.output[Demod.len] = 0xdd;
 572                                         Demod.state = DEMOD_UNSYNCD;
 573                                         break;
 574                         }
 575
 576                         /*if(Demod.bitCount>=9) {
 577                                 Demod.output[Demod.len] = Demod.shiftReg & 0xff;
 578                                 Demod.len++;
 579
 580                                 Demod.parityBits <<= 1;
 581                                 Demod.parityBits ^= ((Demod.shiftReg >> 8) & 0x01);
 582
 583                                 Demod.bitCount = 0;
 584                                 Demod.shiftReg = 0;
 585                         }*/
 586                         if(Demod.bitCount>=8) {
 587                                 Demod.shiftReg >>= 1;
 588                                 Demod.output[Demod.len] = (Demod.shiftReg & 0xff);
 589                                 Demod.len++;
 590                                 Demod.bitCount = 0;
 591                                 Demod.shiftReg = 0;
 592                         }
 593
 594                         if(error) {
 595                                 Demod.output[Demod.len] = 0xBB;
 596                                 Demod.len++;
 597                                 Demod.output[Demod.len] = error & 0xFF;
 598                                 Demod.len++;
 599                                 Demod.output[Demod.len] = 0xBB;
 600                                 Demod.len++;
 601                                 Demod.output[Demod.len] = bit & 0xFF;
 602                                 Demod.len++;
 603                                 Demod.output[Demod.len] = Demod.buffer & 0xFF;
 604                                 Demod.len++;
 605                                 // Look harder ;-)
 606                                 Demod.output[Demod.len] = Demod.buffer2 & 0xFF;
 607                                 Demod.len++;
 608                                 Demod.output[Demod.len] = Demod.syncBit & 0xFF;
 609                                 Demod.len++;
 610                                 Demod.output[Demod.len] = 0xBB;
 611                                 Demod.len++;
 612                                 return TRUE;
 613                         }
 614
 615                 }
 616
 617         } // end (state != UNSYNCED)
 618
 619     return FALSE;
 620 }
 621
 622 //=============================================================================
 623 // Finally, a `sniffer' for iClass communication
 624 // Both sides of communication!
 625 //=============================================================================
 626
 627 //-----------------------------------------------------------------------------
 628 // Record the sequence of commands sent by the reader to the tag, with
 629 // triggering so that we start recording at the point that the tag is moved
 630 // near the reader.
 631 //-----------------------------------------------------------------------------
 632 void RAMFUNC SnoopIClass(void)
 633 {
 634
 635
 636     // We won't start recording the frames that we acquire until we trigger;
 637     // a good trigger condition to get started is probably when we see a
 638     // response from the tag.
 639     //int triggered = FALSE; // FALSE to wait first for card
 640
 641     // The command (reader -> tag) that we're receiving.
 642         // The length of a received command will in most cases be no more than 18 bytes.
 643         // So 32 should be enough!
 644         #define ICLASS_BUFFER_SIZE 32
 645         uint8_t readerToTagCmd[ICLASS_BUFFER_SIZE];
 646     // The response (tag -> reader) that we're receiving.
 647         uint8_t tagToReaderResponse[ICLASS_BUFFER_SIZE];
 648
 649     FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
 650
 651         // free all BigBuf memory
 652         BigBuf_free();
 653     // The DMA buffer, used to stream samples from the FPGA
 654     uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
 655
 656         set_tracing(TRUE);
 657         clear_trace();
 658     iso14a_set_trigger(FALSE);
 659
 660         int lastRxCounter;
 661     uint8_t *upTo;
 662     int smpl;
 663     int maxBehindBy = 0;
 664
 665     // Count of samples received so far, so that we can include timing
 666     // information in the trace buffer.
 667     int samples = 0;
 668     rsamples = 0;
 669
 670     // Set up the demodulator for tag -> reader responses.
 671         Demod.output = tagToReaderResponse;
 672     Demod.len = 0;
 673     Demod.state = DEMOD_UNSYNCD;
 674
 675     // Setup for the DMA.
 676     FpgaSetupSsc();
 677     upTo = dmaBuf;
 678     lastRxCounter = DMA_BUFFER_SIZE;
 679     FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
 680
 681     // And the reader -> tag commands
 682     memset(&Uart, 0, sizeof(Uart));
 683         Uart.output = readerToTagCmd;
 684     Uart.byteCntMax = 32; // was 100 (greg)////////////////////////////////////////////////////////////////////////
 685     Uart.state = STATE_UNSYNCD;
 686
 687     // And put the FPGA in the appropriate mode
 688     // Signal field is off with the appropriate LED
 689     LED_D_OFF();
 690     FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER);
 691     SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
 692
 693         uint32_t time_0 = GetCountSspClk();
 694         uint32_t time_start = 0;
 695         uint32_t time_stop  = 0;
 696
 697     int div = 0;
 698     //int div2 = 0;
 699     int decbyte = 0;
 700     int decbyter = 0;
 701
 702     // And now we loop, receiving samples.
 703     for(;;) {
 704         LED_A_ON();
 705         WDT_HIT();
 706         int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &
 707                                 (DMA_BUFFER_SIZE-1);
 708         if(behindBy > maxBehindBy) {
 709             maxBehindBy = behindBy;
 710             if(behindBy > (9 * DMA_BUFFER_SIZE / 10)) {
 711                 Dbprintf("blew circular buffer! behindBy=0x%x", behindBy);
 712                 goto done;
 713             }
 714         }
 715         if(behindBy < 1) continue;
 716
 717         LED_A_OFF();
 718         smpl = upTo[0];
 719         upTo++;
 720         lastRxCounter -= 1;
 721         if(upTo - dmaBuf > DMA_BUFFER_SIZE) {
 722             upTo -= DMA_BUFFER_SIZE;
 723             lastRxCounter += DMA_BUFFER_SIZE;
 724             AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
 725             AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
 726         }
 727
 728         //samples += 4;
 729         samples += 1;
 730
 731         if(smpl & 0xF) {
 732                 decbyte ^= (1 << (3 - div));
 733         }
 734
 735         // FOR READER SIDE COMMUMICATION...
 736
 737         decbyter <<= 2;
 738         decbyter ^= (smpl & 0x30);
 739
 740         div++;
 741
 742         if((div + 1) % 2 == 0) {
 743                 smpl = decbyter;
 744                 if(OutOfNDecoding((smpl & 0xF0) >> 4)) {
 745                     rsamples = samples - Uart.samples;
 746                         time_stop = (GetCountSspClk()-time_0) << 4;
 747                     LED_C_ON();
 748
 749                         //if(!LogTrace(Uart.output,Uart.byteCnt, rsamples, Uart.parityBits,TRUE)) break;
 750                         //if(!LogTrace(NULL, 0, Uart.endTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER, 0, TRUE)) break;
 751                         if(tracing)     {
 752                                 uint8_t parity[MAX_PARITY_SIZE];
 753                                 GetParity(Uart.output, Uart.byteCnt, parity);
 754                                 LogTrace(Uart.output,Uart.byteCnt, time_start, time_stop, parity, TRUE);
 755                         }
 756
 757
 758                         /* And ready to receive another command. */
 759                     Uart.state = STATE_UNSYNCD;
 760                     /* And also reset the demod code, which might have been */
 761                     /* false-triggered by the commands from the reader. */
 762                     Demod.state = DEMOD_UNSYNCD;
 763                     LED_B_OFF();
 764                     Uart.byteCnt = 0;
 765                 }else{
 766                         time_start = (GetCountSspClk()-time_0) << 4;
 767                 }
 768                 decbyter = 0;
 769         }
 770
 771         if(div > 3) {
 772                 smpl = decbyte;
 773                 if(ManchesterDecoding(smpl & 0x0F)) {
 774                         time_stop = (GetCountSspClk()-time_0) << 4;
 775
 776                         rsamples = samples - Demod.samples;
 777                     LED_B_ON();
 778
 779                         if(tracing)     {
 780                                 uint8_t parity[MAX_PARITY_SIZE];
 781                                 GetParity(Demod.output, Demod.len, parity);
 782                                 LogTrace(Demod.output, Demod.len, time_start, time_stop, parity, FALSE);
 783                         }
 784
 785                     // And ready to receive another response.
 786                     memset(&Demod, 0, sizeof(Demod));
 787                         Demod.output = tagToReaderResponse;
 788                     Demod.state = DEMOD_UNSYNCD;
 789                     LED_C_OFF();
 790                 }else{
 791                         time_start = (GetCountSspClk()-time_0) << 4;
 792                 }
 793
 794                 div = 0;
 795                 decbyte = 0x00;
 796         }
 797         //}
 798
 799         if(BUTTON_PRESS()) {
 800             DbpString("cancelled_a");
 801             goto done;
 802         }
 803     }
 804
 805     DbpString("COMMAND FINISHED");
 806
 807     Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
 808         Dbprintf("%x %x %x", Uart.byteCntMax, BigBuf_get_traceLen(), (int)Uart.output[0]);
 809
 810 done:
 811     AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
 812     Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
 813         Dbprintf("%x %x %x", Uart.byteCntMax, BigBuf_get_traceLen(), (int)Uart.output[0]);
 814     LED_A_OFF();
 815     LED_B_OFF();
 816     LED_C_OFF();
 817     LED_D_OFF();
 818 }
 819
 820 void rotateCSN(uint8_t* originalCSN, uint8_t* rotatedCSN) {
 821         int i;
 822         for(i = 0; i < 8; i++) {
 823                 rotatedCSN[i] = (originalCSN[i] >> 3) | (originalCSN[(i+1)%8] << 5);
 824         }
 825 }
 826
 827 //-----------------------------------------------------------------------------
 828 // Wait for commands from reader
 829 // Stop when button is pressed
 830 // Or return TRUE when command is captured
 831 //-----------------------------------------------------------------------------
 832 static int GetIClassCommandFromReader(uint8_t *received, int *len, int maxLen)
 833 {
 834     // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
 835     // only, since we are receiving, not transmitting).
 836     // Signal field is off with the appropriate LED
 837     LED_D_OFF();
 838     FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
 839
 840     // Now run a `software UART' on the stream of incoming samples.
 841     Uart.output = received;
 842     Uart.byteCntMax = maxLen;
 843     Uart.state = STATE_UNSYNCD;
 844
 845     for(;;) {
 846         WDT_HIT();
 847
 848         if(BUTTON_PRESS()) return FALSE;
 849
 850         if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
 851             AT91C_BASE_SSC->SSC_THR = 0x00;
 852         }
 853         if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
 854             uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
 855
 856                         if(OutOfNDecoding(b & 0x0f)) {
 857                                 *len = Uart.byteCnt;
 858                                 return TRUE;
 859                         }
 860         }
 861     }
 862 }
 863
 864 static uint8_t encode4Bits(const uint8_t b)
 865 {
 866         uint8_t c = b & 0xF;
 867         // OTA, the least significant bits first
 868         //         The columns are
 869         //               1 - Bit value to send
 870         //               2 - Reversed (big-endian)
 871         //               3 - Encoded
 872         //               4 - Hex values
 873
 874         switch(c){
 875         //                          1       2         3         4
 876           case 15: return 0x55; // 1111 -> 1111 -> 01010101 -> 0x55
 877           case 14: return 0x95; // 1110 -> 0111 -> 10010101 -> 0x95
 878           case 13: return 0x65; // 1101 -> 1011 -> 01100101 -> 0x65
 879           case 12: return 0xa5; // 1100 -> 0011 -> 10100101 -> 0xa5
 880           case 11: return 0x59; // 1011 -> 1101 -> 01011001 -> 0x59
 881           case 10: return 0x99; // 1010 -> 0101 -> 10011001 -> 0x99
 882           case 9:  return 0x69; // 1001 -> 1001 -> 01101001 -> 0x69
 883           case 8:  return 0xa9; // 1000 -> 0001 -> 10101001 -> 0xa9
 884           case 7:  return 0x56; // 0111 -> 1110 -> 01010110 -> 0x56
 885           case 6:  return 0x96; // 0110 -> 0110 -> 10010110 -> 0x96
 886           case 5:  return 0x66; // 0101 -> 1010 -> 01100110 -> 0x66
 887           case 4:  return 0xa6; // 0100 -> 0010 -> 10100110 -> 0xa6
 888           case 3:  return 0x5a; // 0011 -> 1100 -> 01011010 -> 0x5a
 889           case 2:  return 0x9a; // 0010 -> 0100 -> 10011010 -> 0x9a
 890           case 1:  return 0x6a; // 0001 -> 1000 -> 01101010 -> 0x6a
 891           default: return 0xaa; // 0000 -> 0000 -> 10101010 -> 0xaa
 892
 893         }
 894 }
 895
 896 //-----------------------------------------------------------------------------
 897 // Prepare tag messages
 898 //-----------------------------------------------------------------------------
 899 static void CodeIClassTagAnswer(const uint8_t *cmd, int len)
 900 {
 901
 902         /*
 903          * SOF comprises 3 parts;
 904          * * An unmodulated time of 56.64 us
 905          * * 24 pulses of 423.75 KHz (fc/32)
 906          * * A logic 1, which starts with an unmodulated time of 18.88us
 907          *   followed by 8 pulses of 423.75kHz (fc/32)
 908          *
 909          *
 910          * EOF comprises 3 parts:
 911          * - A logic 0 (which starts with 8 pulses of fc/32 followed by an unmodulated
 912          *   time of 18.88us.
 913          * - 24 pulses of fc/32
 914          * - An unmodulated time of 56.64 us
 915          *
 916          *
 917          * A logic 0 starts with 8 pulses of fc/32
 918          * followed by an unmodulated time of 256/fc (~18,88us).
 919          *
 920          * A logic 0 starts with unmodulated time of 256/fc (~18,88us) followed by
 921          * 8 pulses of fc/32 (also 18.88us)
 922          *
 923          * The mode FPGA_HF_SIMULATOR_MODULATE_424K_8BIT which we use to simulate tag,
 924          * works like this.
 925          * - A 1-bit input to the FPGA becomes 8 pulses on 423.5kHz (fc/32) (18.88us).
 926          * - A 0-bit inptu to the FPGA becomes an unmodulated time of 18.88us
 927          *
 928          * In this mode the SOF can be written as 00011101 = 0x1D
 929          * The EOF can be written as 10111000 = 0xb8
 930          * A logic 1 is 01
 931          * A logic 0 is 10
 932          *
 933          * */
 934
 935         int i;
 936
 937         ToSendReset();
 938
 939         // Send SOF
 940         ToSend[++ToSendMax] = 0x1D;
 941
 942         for(i = 0; i < len; i++) {
 943                 uint8_t b = cmd[i];
 944                 ToSend[++ToSendMax] = encode4Bits(b & 0xF); //Least significant half
 945                 ToSend[++ToSendMax] = encode4Bits((b >>4) & 0xF);//Most significant half
 946         }
 947
 948         // Send EOF
 949         ToSend[++ToSendMax] = 0xB8;
 950         //lastProxToAirDuration  = 8*ToSendMax - 3*8 - 3*8;//Not counting zeroes in the beginning or end
 951         // Convert from last byte pos to length
 952         ToSendMax++;
 953 }
 954
 955 // Only SOF
 956 static void CodeIClassTagSOF()
 957 {
 958         //So far a dummy implementation, not used
 959         //int lastProxToAirDuration =0;
 960
 961         ToSendReset();
 962         // Send SOF
 963         ToSend[++ToSendMax] = 0x1D;
 964 //      lastProxToAirDuration  = 8*ToSendMax - 3*8;//Not counting zeroes in the beginning
 965
 966         // Convert from last byte pos to length
 967         ToSendMax++;
 968 }
 969 #define MODE_SIM_CSN        0
 970 #define MODE_EXIT_AFTER_MAC 1
 971 #define MODE_FULLSIM        2
 972
 973 int doIClassSimulation(int simulationMode, uint8_t *reader_mac_buf);
 974 /**
 975  * @brief SimulateIClass simulates an iClass card.
 976  * @param arg0 type of simulation
 977  *                      - 0 uses the first 8 bytes in usb data as CSN
 978  *                      - 2 "dismantling iclass"-attack. This mode iterates through all CSN's specified
 979  *                      in the usb data. This mode collects MAC from the reader, in order to do an offline
 980  *                      attack on the keys. For more info, see "dismantling iclass" and proxclone.com.
 981  *                      - Other : Uses the default CSN (031fec8af7ff12e0)
 982  * @param arg1 - number of CSN's contained in datain (applicable for mode 2 only)
 983  * @param arg2
 984  * @param datain
 985  */
 986 void SimulateIClass(uint32_t arg0, uint32_t arg1, uint32_t arg2, uint8_t *datain)
 987 {
 988         uint32_t simType = arg0;
 989         uint32_t numberOfCSNS = arg1;
 990         FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
 991
 992         // Enable and clear the trace
 993         set_tracing(TRUE);
 994         clear_trace();
 995         //Use the emulator memory for SIM
 996         uint8_t *emulator = BigBuf_get_EM_addr();
 997
 998         if(simType == 0) {
 999                 // Use the CSN from commandline
1000                 memcpy(emulator, datain, 8);
1001                 doIClassSimulation(MODE_SIM_CSN,NULL);
1002         }else if(simType == 1)
1003         {
1004                 //Default CSN
1005                 uint8_t csn_crc[] = { 0x03, 0x1f, 0xec, 0x8a, 0xf7, 0xff, 0x12, 0xe0, 0x00, 0x00 };
1006                 // Use the CSN from commandline
1007                 memcpy(emulator, csn_crc, 8);
1008                 doIClassSimulation(MODE_SIM_CSN,NULL);
1009         }
1010         else if(simType == 2)
1011         {
1012
1013                 uint8_t mac_responses[USB_CMD_DATA_SIZE] = { 0 };
1014                 Dbprintf("Going into attack mode, %d CSNS sent", numberOfCSNS);
1015                 // In this mode, a number of csns are within datain. We'll simulate each one, one at a time
1016                 // in order to collect MAC's from the reader. This can later be used in an offlne-attack
1017                 // in order to obtain the keys, as in the "dismantling iclass"-paper.
1018                 int i = 0;
1019                 for( ; i < numberOfCSNS && i*8+8 < USB_CMD_DATA_SIZE; i++)
1020                 {
1021                         // The usb data is 512 bytes, fitting 65 8-byte CSNs in there.
1022
1023                         memcpy(emulator, datain+(i*8), 8);
1024                         if(doIClassSimulation(MODE_EXIT_AFTER_MAC,mac_responses+i*8))
1025                         {
1026                                 cmd_send(CMD_ACK,CMD_SIMULATE_TAG_ICLASS,i,0,mac_responses,i*8);
1027                                 return; // Button pressed
1028                         }
1029                 }
1030                 cmd_send(CMD_ACK,CMD_SIMULATE_TAG_ICLASS,i,0,mac_responses,i*8);
1031
1032         }else if(simType == 3){
1033                 //This is 'full sim' mode, where we use the emulator storage for data.
1034                 doIClassSimulation(MODE_FULLSIM, NULL);
1035         }
1036         else{
1037                 // We may want a mode here where we hardcode the csns to use (from proxclone).
1038                 // That will speed things up a little, but not required just yet.
1039                 Dbprintf("The mode is not implemented, reserved for future use");
1040         }
1041         Dbprintf("Done...");
1042
1043 }
1044
1045 /**
1046  * @brief Does the actual simulation
1047  * @param csn - csn to use
1048  * @param breakAfterMacReceived if true, returns after reader MAC has been received.
1049  */
1050 int doIClassSimulation( int simulationMode, uint8_t *reader_mac_buf)
1051 {
1052         // free eventually allocated BigBuf memory
1053         BigBuf_free_keep_EM();
1054
1055         uint8_t *csn = BigBuf_get_EM_addr();
1056         uint8_t *emulator = csn;
1057         uint8_t sof_data[] = { 0x0F} ;
1058         // CSN followed by two CRC bytes
1059         uint8_t anticoll_data[10] = { 0 };
1060         uint8_t csn_data[10] = { 0 };
1061         memcpy(csn_data,csn,sizeof(csn_data));
1062         Dbprintf("Simulating CSN %02x%02x%02x%02x%02x%02x%02x%02x",csn[0],csn[1],csn[2],csn[3],csn[4],csn[5],csn[6],csn[7]);
1063
1064         // Construct anticollision-CSN
1065         rotateCSN(csn_data,anticoll_data);
1066
1067         // Compute CRC on both CSNs
1068         ComputeCrc14443(CRC_ICLASS, anticoll_data, 8, &anticoll_data[8], &anticoll_data[9]);
1069         ComputeCrc14443(CRC_ICLASS, csn_data, 8, &csn_data[8], &csn_data[9]);
1070
1071         // e-Purse
1072         uint8_t card_challenge_data[8] = { 0x00 };
1073         if(simulationMode == MODE_FULLSIM)
1074         {
1075                 //Card challenge, a.k.a e-purse is on block 2
1076                 memcpy(card_challenge_data,emulator + (8 * 2) , 8);
1077         }
1078
1079         int exitLoop = 0;
1080         // Reader 0a
1081         // Tag    0f
1082         // Reader 0c
1083         // Tag    anticoll. CSN
1084         // Reader 81 anticoll. CSN
1085         // Tag    CSN
1086
1087         uint8_t *modulated_response;
1088         int modulated_response_size = 0;
1089         uint8_t* trace_data = NULL;
1090         int trace_data_size = 0;
1091
1092
1093         // Respond SOF -- takes 1 bytes
1094         uint8_t *resp_sof = BigBuf_malloc(2);
1095         int resp_sof_Len;
1096
1097         // Anticollision CSN (rotated CSN)
1098         // 22: Takes 2 bytes for SOF/EOF and 10 * 2 = 20 bytes (2 bytes/byte)
1099         uint8_t *resp_anticoll = BigBuf_malloc(28);
1100         int resp_anticoll_len;
1101
1102         // CSN
1103         // 22: Takes 2 bytes for SOF/EOF and 10 * 2 = 20 bytes (2 bytes/byte)
1104         uint8_t *resp_csn = BigBuf_malloc(30);
1105         int resp_csn_len;
1106
1107         // e-Purse
1108         // 18: Takes 2 bytes for SOF/EOF and 8 * 2 = 16 bytes (2 bytes/bit)
1109         uint8_t *resp_cc = BigBuf_malloc(20);
1110         int resp_cc_len;
1111
1112         uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
1113         memset(receivedCmd, 0x44, MAX_FRAME_SIZE);
1114         int len;
1115
1116         // Prepare card messages
1117         ToSendMax = 0;
1118
1119         // First card answer: SOF
1120         CodeIClassTagSOF();
1121         memcpy(resp_sof, ToSend, ToSendMax); resp_sof_Len = ToSendMax;
1122
1123         // Anticollision CSN
1124         CodeIClassTagAnswer(anticoll_data, sizeof(anticoll_data));
1125         memcpy(resp_anticoll, ToSend, ToSendMax); resp_anticoll_len = ToSendMax;
1126
1127         // CSN
1128         CodeIClassTagAnswer(csn_data, sizeof(csn_data));
1129         memcpy(resp_csn, ToSend, ToSendMax); resp_csn_len = ToSendMax;
1130
1131         // e-Purse
1132         CodeIClassTagAnswer(card_challenge_data, sizeof(card_challenge_data));
1133         memcpy(resp_cc, ToSend, ToSendMax); resp_cc_len = ToSendMax;
1134
1135         //This is used for responding to READ-block commands or other data which is dynamically generated
1136         uint8_t *data_response = BigBuf_malloc(8 * 2 + 2);
1137         //This is used for responding to READ-block commands or other data which is dynamically generated
1138         uint8_t *data_generic_trace = BigBuf_malloc(8 * 2 + 2);
1139
1140         // Start from off (no field generated)
1141         //FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1142         //SpinDelay(200);
1143         FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
1144         SpinDelay(100);
1145         StartCountSspClk();
1146         // We need to listen to the high-frequency, peak-detected path.
1147         SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
1148         FpgaSetupSsc();
1149
1150         // To control where we are in the protocol
1151         int cmdsRecvd = 0;
1152         uint32_t time_0 = GetCountSspClk();
1153         uint32_t t2r_time =0;
1154         uint32_t r2t_time =0;
1155
1156         LED_A_ON();
1157         bool buttonPressed = false;
1158
1159         while(!exitLoop) {
1160
1161                 LED_B_OFF();
1162                 //Signal tracer
1163                 // Can be used to get a trigger for an oscilloscope..
1164                 LED_C_OFF();
1165
1166                 if(!GetIClassCommandFromReader(receivedCmd, &len, 100)) {
1167                         buttonPressed = true;
1168                         break;
1169                 }
1170                 r2t_time = GetCountSspClk();
1171                 //Signal tracer
1172                 LED_C_ON();
1173
1174                 // Okay, look at the command now.
1175                 if(receivedCmd[0] == ICLASS_CMD_ACTALL ) {
1176                         // Reader in anticollission phase
1177                         modulated_response = resp_sof; modulated_response_size = resp_sof_Len; //order = 1;
1178                         trace_data = sof_data;
1179                         trace_data_size = sizeof(sof_data);
1180                 } else if(receivedCmd[0] == ICLASS_CMD_READ_OR_IDENTIFY && len == 1) {
1181                         // Reader asks for anticollission CSN
1182                         modulated_response = resp_anticoll; modulated_response_size = resp_anticoll_len; //order = 2;
1183                         trace_data = anticoll_data;
1184                         trace_data_size = sizeof(anticoll_data);
1185                         //DbpString("Reader requests anticollission CSN:");
1186                 } else if(receivedCmd[0] == ICLASS_CMD_SELECT) {
1187                         // Reader selects anticollission CSN.
1188                         // Tag sends the corresponding real CSN
1189                         modulated_response = resp_csn; modulated_response_size = resp_csn_len; //order = 3;
1190                         trace_data = csn_data;
1191                         trace_data_size = sizeof(csn_data);
1192                         //DbpString("Reader selects anticollission CSN:");
1193                 } else if(receivedCmd[0] == ICLASS_CMD_READCHECK_KD) {
1194                         // Read e-purse (88 02)
1195                         modulated_response = resp_cc; modulated_response_size = resp_cc_len; //order = 4;
1196                         trace_data = card_challenge_data;
1197                         trace_data_size = sizeof(card_challenge_data);
1198                         LED_B_ON();
1199                 } else if(receivedCmd[0] == ICLASS_CMD_CHECK) {
1200                         // Reader random and reader MAC!!!
1201                         if(simulationMode == MODE_FULLSIM)
1202                         {       //This is what we must do..
1203                                 //Reader just sent us NR and MAC(k,cc * nr)
1204                                 //The diversified key should be stored on block 3
1205                                 //However, from a typical dump, the key will not be there
1206                                 uint8_t diversified_key[8] = { 0 };
1207
1208                                 //Get the diversified key from emulator memory
1209                                 memcpy(diversified_key, emulator+(8*3),8);
1210                                 uint8_t ccnr[12] = { 0 };
1211                                 //Put our cc there (block 2)
1212                                 memcpy(ccnr, emulator + (8 * 2), 8);
1213                                 //Put nr there
1214                                 memcpy(ccnr+8, receivedCmd+1,4);
1215                                 //Now, calc MAC
1216                                 doMAC(ccnr,diversified_key, data_generic_trace);
1217                                 trace_data = data_generic_trace;
1218                                 trace_data_size = 4;
1219                                 CodeIClassTagAnswer(trace_data , trace_data_size);
1220                                 memcpy(data_response, ToSend, ToSendMax);
1221                                 modulated_response = data_response;
1222                                 modulated_response_size = ToSendMax;
1223                         }else
1224                         {       //Not fullsim, we don't respond
1225                                 // We do not know what to answer, so lets keep quiet
1226                                 modulated_response = resp_sof; modulated_response_size = 0;
1227                                 trace_data = NULL;
1228                                 trace_data_size = 0;
1229                                 if (simulationMode == MODE_EXIT_AFTER_MAC){
1230                                         // dbprintf:ing ...
1231                                         Dbprintf("CSN: %02x %02x %02x %02x %02x %02x %02x %02x"
1232                                                            ,csn[0],csn[1],csn[2],csn[3],csn[4],csn[5],csn[6],csn[7]);
1233                                         Dbprintf("RDR:  (len=%02d): %02x %02x %02x %02x %02x %02x %02x %02x %02x",len,
1234                                                         receivedCmd[0], receivedCmd[1], receivedCmd[2],
1235                                                         receivedCmd[3], receivedCmd[4], receivedCmd[5],
1236                                                         receivedCmd[6], receivedCmd[7], receivedCmd[8]);
1237                                         if (reader_mac_buf != NULL)
1238                                         {
1239                                                 memcpy(reader_mac_buf,receivedCmd+1,8);
1240                                         }
1241                                         exitLoop = true;
1242                                 }
1243                         }
1244
1245                 } else if(receivedCmd[0] == ICLASS_CMD_HALT && len == 1) {
1246                         // Reader ends the session
1247                         modulated_response = resp_sof; modulated_response_size = 0; //order = 0;
1248                         trace_data = NULL;
1249                         trace_data_size = 0;
1250                 } else if(simulationMode == MODE_FULLSIM && receivedCmd[0] == ICLASS_CMD_READ_OR_IDENTIFY && len == 4){
1251                         //Read block
1252                         uint16_t blk = receivedCmd[1];
1253                         trace_data = emulator+(blk << 3);
1254                         trace_data_size = 8;
1255                         CodeIClassTagAnswer(trace_data , trace_data_size);
1256                         memcpy(data_response, ToSend, ToSendMax);
1257                         modulated_response = data_response;
1258                         modulated_response_size = ToSendMax;
1259                 }
1260                 else if(receivedCmd[0] == ICLASS_CMD_PAGESEL)
1261                 {//Pagesel
1262                         //Pagesel enables to select a page in the selected chip memory and return its configuration block
1263                         //Chips with a single page will not answer to this command
1264                         // It appears we're fine ignoring this.
1265                         //Otherwise, we should answer 8bytes (block) + 2bytes CRC
1266                 }
1267                 else {
1268                         //#db# Unknown command received from reader (len=5): 26 1 0 f6 a 44 44 44 44
1269                         // Never seen this command before
1270                         Dbprintf("Unknown command received from reader (len=%d): %x %x %x %x %x %x %x %x %x",
1271                         len,
1272                         receivedCmd[0], receivedCmd[1], receivedCmd[2],
1273                         receivedCmd[3], receivedCmd[4], receivedCmd[5],
1274                         receivedCmd[6], receivedCmd[7], receivedCmd[8]);
1275                         // Do not respond
1276                         modulated_response = resp_sof; modulated_response_size = 0; //order = 0;
1277                         trace_data = NULL;
1278                         trace_data_size = 0;
1279                 }
1280
1281                 if(cmdsRecvd >  100) {
1282                         //DbpString("100 commands later...");
1283                         //break;
1284                 }
1285                 else {
1286                         cmdsRecvd++;
1287                 }
1288                 /**
1289                 A legit tag has about 380us delay between reader EOT and tag SOF.
1290                 **/
1291                 if(modulated_response_size > 0) {
1292                         SendIClassAnswer(modulated_response, modulated_response_size, 1);
1293                         t2r_time = GetCountSspClk();
1294                 }
1295
1296                 if (tracing) {
1297                         uint8_t parity[MAX_PARITY_SIZE];
1298                         GetParity(receivedCmd, len, parity);
1299                         LogTrace(receivedCmd,len, (r2t_time-time_0)<< 4, (r2t_time-time_0) << 4, parity, TRUE);
1300
1301                         if (trace_data != NULL) {
1302                                 GetParity(trace_data, trace_data_size, parity);
1303                                 LogTrace(trace_data, trace_data_size, (t2r_time-time_0) << 4, (t2r_time-time_0) << 4, parity, FALSE);
1304                         }
1305                         if(!tracing) {
1306                                 DbpString("Trace full");
1307                                 //break;
1308                         }
1309
1310                 }
1311                 memset(receivedCmd, 0x44, MAX_FRAME_SIZE);
1312         }
1313
1314         //Dbprintf("%x", cmdsRecvd);
1315         LED_A_OFF();
1316         LED_B_OFF();
1317         LED_C_OFF();
1318
1319         if(buttonPressed)
1320         {
1321                 DbpString("Button pressed");
1322         }
1323         return buttonPressed;
1324 }
1325
1326 static int SendIClassAnswer(uint8_t *resp, int respLen, int delay)
1327 {
1328         int i = 0, d=0;//, u = 0, d = 0;
1329         uint8_t b = 0;
1330
1331         //FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR|FPGA_HF_SIMULATOR_MODULATE_424K);
1332         FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR|FPGA_HF_SIMULATOR_MODULATE_424K_8BIT);
1333
1334         AT91C_BASE_SSC->SSC_THR = 0x00;
1335         FpgaSetupSsc();
1336         while(!BUTTON_PRESS()) {
1337                 if((AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)){
1338                         b = AT91C_BASE_SSC->SSC_RHR; (void) b;
1339                 }
1340                 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)){
1341                         b = 0x00;
1342                         if(d < delay) {
1343                                 d++;
1344                         }
1345                         else {
1346                                 if( i < respLen){
1347                                         b = resp[i];
1348                                         //Hack
1349                                         //b = 0xAC;
1350                                 }
1351                                 i++;
1352                         }
1353                         AT91C_BASE_SSC->SSC_THR = b;
1354                 }
1355
1356 //              if (i > respLen +4) break;
1357                 if (i > respLen +1) break;
1358         }
1359
1360         return 0;
1361 }
1362
1363 /// THE READER CODE
1364
1365 //-----------------------------------------------------------------------------
1366 // Transmit the command (to the tag) that was placed in ToSend[].
1367 //-----------------------------------------------------------------------------
1368 static void TransmitIClassCommand(const uint8_t *cmd, int len, int *samples, int *wait)
1369 {
1370   int c;
1371   FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1372   AT91C_BASE_SSC->SSC_THR = 0x00;
1373   FpgaSetupSsc();
1374
1375    if (wait)
1376    {
1377      if(*wait < 10) *wait = 10;
1378
1379      for(c = 0; c < *wait;) {
1380        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1381          AT91C_BASE_SSC->SSC_THR = 0x00;                // For exact timing!
1382          c++;
1383        }
1384        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1385          volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
1386          (void)r;
1387        }
1388        WDT_HIT();
1389      }
1390
1391    }
1392
1393
1394   uint8_t sendbyte;
1395   bool firstpart = TRUE;
1396   c = 0;
1397   for(;;) {
1398     if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1399
1400       // DOUBLE THE SAMPLES!
1401       if(firstpart) {
1402         sendbyte = (cmd[c] & 0xf0) | (cmd[c] >> 4);
1403       }
1404       else {
1405         sendbyte = (cmd[c] & 0x0f) | (cmd[c] << 4);
1406         c++;
1407       }
1408       if(sendbyte == 0xff) {
1409         sendbyte = 0xfe;
1410       }
1411       AT91C_BASE_SSC->SSC_THR = sendbyte;
1412       firstpart = !firstpart;
1413
1414       if(c >= len) {
1415         break;
1416       }
1417     }
1418     if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1419       volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
1420       (void)r;
1421     }
1422     WDT_HIT();
1423   }
1424   if (samples) *samples = (c + *wait) << 3;
1425 }
1426
1427
1428 //-----------------------------------------------------------------------------
1429 // Prepare iClass reader command to send to FPGA
1430 //-----------------------------------------------------------------------------
1431 void CodeIClassCommand(const uint8_t * cmd, int len)
1432 {
1433   int i, j, k;
1434   uint8_t b;
1435
1436   ToSendReset();
1437
1438   // Start of Communication: 1 out of 4
1439   ToSend[++ToSendMax] = 0xf0;
1440   ToSend[++ToSendMax] = 0x00;
1441   ToSend[++ToSendMax] = 0x0f;
1442   ToSend[++ToSendMax] = 0x00;
1443
1444   // Modulate the bytes
1445   for (i = 0; i < len; i++) {
1446     b = cmd[i];
1447     for(j = 0; j < 4; j++) {
1448       for(k = 0; k < 4; k++) {
1449                         if(k == (b & 3)) {
1450                                 ToSend[++ToSendMax] = 0x0f;
1451                         }
1452                         else {
1453                                 ToSend[++ToSendMax] = 0x00;
1454                         }
1455       }
1456       b >>= 2;
1457     }
1458   }
1459
1460   // End of Communication
1461   ToSend[++ToSendMax] = 0x00;
1462   ToSend[++ToSendMax] = 0x00;
1463   ToSend[++ToSendMax] = 0xf0;
1464   ToSend[++ToSendMax] = 0x00;
1465
1466   // Convert from last character reference to length
1467   ToSendMax++;
1468 }
1469
1470 void ReaderTransmitIClass(uint8_t* frame, int len)
1471 {
1472         int wait = 0;
1473         int samples = 0;
1474
1475         // This is tied to other size changes
1476         CodeIClassCommand(frame,len);
1477
1478         // Select the card
1479         TransmitIClassCommand(ToSend, ToSendMax, &samples, &wait);
1480         if(trigger)
1481                 LED_A_ON();
1482
1483         // Store reader command in buffer
1484         if (tracing) {
1485                 uint8_t par[MAX_PARITY_SIZE];
1486                 GetParity(frame, len, par);
1487                 LogTrace(frame, len, rsamples, rsamples, par, TRUE);
1488         }
1489 }
1490
1491 //-----------------------------------------------------------------------------
1492 // Wait a certain time for tag response
1493 //  If a response is captured return TRUE
1494 //  If it takes too long return FALSE
1495 //-----------------------------------------------------------------------------
1496 static int GetIClassAnswer(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer
1497 {
1498         // buffer needs to be 512 bytes
1499         int c;
1500
1501         // Set FPGA mode to "reader listen mode", no modulation (listen
1502         // only, since we are receiving, not transmitting).
1503         FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);
1504
1505         // Now get the answer from the card
1506         Demod.output = receivedResponse;
1507         Demod.len = 0;
1508         Demod.state = DEMOD_UNSYNCD;
1509
1510         uint8_t b;
1511         if (elapsed) *elapsed = 0;
1512
1513         bool skip = FALSE;
1514
1515         c = 0;
1516         for(;;) {
1517                 WDT_HIT();
1518
1519                 if(BUTTON_PRESS()) return FALSE;
1520
1521                 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1522                         AT91C_BASE_SSC->SSC_THR = 0x00;  // To make use of exact timing of next command from reader!!
1523                         if (elapsed) (*elapsed)++;
1524                 }
1525                 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1526                         if(c < timeout) { c++; } else { return FALSE; }
1527                         b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1528                         skip = !skip;
1529                         if(skip) continue;
1530
1531                         if(ManchesterDecoding(b & 0x0f)) {
1532                                 *samples = c << 3;
1533                                 return  TRUE;
1534                         }
1535                 }
1536         }
1537 }
1538
1539 int ReaderReceiveIClass(uint8_t* receivedAnswer)
1540 {
1541   int samples = 0;
1542   if (!GetIClassAnswer(receivedAnswer,160,&samples,0)) return FALSE;
1543   rsamples += samples;
1544   if (tracing) {
1545         uint8_t parity[MAX_PARITY_SIZE];
1546         GetParity(receivedAnswer, Demod.len, parity);
1547         LogTrace(receivedAnswer,Demod.len,rsamples,rsamples,parity,FALSE);
1548   }
1549   if(samples == 0) return FALSE;
1550   return Demod.len;
1551 }
1552
1553 void setupIclassReader()
1554 {
1555     FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
1556     // Reset trace buffer
1557         set_tracing(TRUE);
1558         clear_trace();
1559
1560     // Setup SSC
1561     FpgaSetupSsc();
1562     // Start from off (no field generated)
1563     // Signal field is off with the appropriate LED
1564     LED_D_OFF();
1565     FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1566     SpinDelay(200);
1567
1568     SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
1569
1570     // Now give it time to spin up.
1571     // Signal field is on with the appropriate LED
1572     FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1573     SpinDelay(200);
1574     LED_A_ON();
1575
1576 }
1577
1578 size_t sendCmdGetResponseWithRetries(uint8_t* command, size_t cmdsize, uint8_t* resp, uint8_t expected_size, uint8_t retries)
1579 {
1580         while(retries-- > 0)
1581         {
1582                 ReaderTransmitIClass(command, cmdsize);
1583                 if(expected_size == ReaderReceiveIClass(resp)){
1584                         return 0;
1585                 }
1586         }
1587         return 1;//Error
1588 }
1589
1590 /**
1591  * @brief Talks to an iclass tag, sends the commands to get CSN and CC.
1592  * @param card_data where the CSN and CC are stored for return
1593  * @return 0 = fail
1594  *         1 = Got CSN
1595  *         2 = Got CSN and CC
1596  */
1597 uint8_t handshakeIclassTag(uint8_t *card_data)
1598 {
1599         static uint8_t act_all[]     = { 0x0a };
1600         static uint8_t identify[]    = { 0x0c };
1601         static uint8_t select[]      = { 0x81, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
1602         static uint8_t readcheck_cc[]= { 0x88, 0x02 };
1603         uint8_t resp[ICLASS_BUFFER_SIZE];
1604
1605         uint8_t read_status = 0;
1606
1607         // Send act_all
1608         ReaderTransmitIClass(act_all, 1);
1609         // Card present?
1610         if(!ReaderReceiveIClass(resp)) return read_status;//Fail
1611         //Send Identify
1612         ReaderTransmitIClass(identify, 1);
1613         //We expect a 10-byte response here, 8 byte anticollision-CSN and 2 byte CRC
1614         uint8_t len  = ReaderReceiveIClass(resp);
1615         if(len != 10) return read_status;//Fail
1616
1617         //Copy the Anti-collision CSN to our select-packet
1618         memcpy(&select[1],resp,8);
1619         //Select the card
1620         ReaderTransmitIClass(select, sizeof(select));
1621         //We expect a 10-byte response here, 8 byte CSN and 2 byte CRC
1622         len  = ReaderReceiveIClass(resp);
1623         if(len != 10) return read_status;//Fail
1624
1625         //Success - level 1, we got CSN
1626         //Save CSN in response data
1627         memcpy(card_data,resp,8);
1628
1629         //Flag that we got to at least stage 1, read CSN
1630         read_status = 1;
1631
1632         // Card selected, now read e-purse (cc)
1633         ReaderTransmitIClass(readcheck_cc, sizeof(readcheck_cc));
1634         if(ReaderReceiveIClass(resp) == 8) {
1635                 //Save CC (e-purse) in response data
1636                 memcpy(card_data+8,resp,8);
1637
1638                 //Got both
1639                 read_status = 2;
1640         }
1641
1642         return read_status;
1643 }
1644
1645 // Reader iClass Anticollission
1646 void ReaderIClass(uint8_t arg0) {
1647
1648     uint8_t card_data[24]={0};
1649     uint8_t last_csn[8]={0};
1650
1651     int read_status= 0;
1652     bool abort_after_read = arg0 & FLAG_ICLASS_READER_ONLY_ONCE;
1653         bool get_cc = arg0 & FLAG_ICLASS_READER_GET_CC;
1654         set_tracing(TRUE);
1655     setupIclassReader();
1656
1657     size_t datasize = 0;
1658     while(!BUTTON_PRESS())
1659     {
1660
1661                 if(!tracing) {
1662                         DbpString("Trace full");
1663                         break;
1664                 }
1665                 WDT_HIT();
1666
1667                 read_status = handshakeIclassTag(card_data);
1668
1669                 if(read_status == 0) continue;
1670                 if(read_status == 1) datasize = 8;
1671                 if(read_status == 2) datasize = 16;
1672
1673                 //Todo, read the public blocks 1,5 aswell:
1674                 //
1675                 // 0 : CSN (we already have)
1676                 // 1 : Configuration
1677                 // 2 : e-purse (we already have)
1678                 // (3,4 write-only)
1679                 // 5 Application issuer area
1680                 //
1681                 //Then we can 'ship' back the 8 * 5 bytes of data,
1682                 // with 0xFF:s in block 3 and 4.
1683
1684                 LED_B_ON();
1685                 //Send back to client, but don't bother if we already sent this
1686                 if(memcmp(last_csn, card_data, 8) != 0)
1687                 {
1688
1689                         if(!get_cc || (get_cc && read_status == 2))
1690                         {
1691                                 cmd_send(CMD_ACK,read_status,0,0,card_data,datasize);
1692                                 if(abort_after_read) {
1693                                         LED_A_OFF();
1694                                         return;
1695                                 }
1696                                 //Save that we already sent this....
1697                                 memcpy(last_csn, card_data, 8);
1698                         }
1699                         //If 'get_cc' was specified and we didn't get a CC, we'll just keep trying...
1700                 }
1701                 LED_B_OFF();
1702     }
1703     cmd_send(CMD_ACK,0,0,0,card_data, 0);
1704     LED_A_OFF();
1705 }
1706
1707 void ReaderIClass_Replay(uint8_t arg0, uint8_t *MAC) {
1708
1709         uint8_t card_data[USB_CMD_DATA_SIZE]={0};
1710         uint16_t block_crc_LUT[255] = {0};
1711
1712         {//Generate a lookup table for block crc
1713                 for(int block = 0; block < 255; block++){
1714                         char bl = block;
1715                         block_crc_LUT[block] = iclass_crc16(&bl ,1);
1716                 }
1717         }
1718         //Dbprintf("Lookup table: %02x %02x %02x" ,block_crc_LUT[0],block_crc_LUT[1],block_crc_LUT[2]);
1719
1720         uint8_t check[]       = { 0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
1721         uint8_t read[]        = { 0x0c, 0x00, 0x00, 0x00 };
1722
1723     uint16_t crc = 0;
1724         uint8_t cardsize=0;
1725         uint8_t mem=0;
1726
1727         static struct memory_t{
1728           int k16;
1729           int book;
1730           int k2;
1731           int lockauth;
1732           int keyaccess;
1733         } memory;
1734
1735         uint8_t resp[ICLASS_BUFFER_SIZE];
1736
1737     setupIclassReader();
1738         set_tracing(TRUE);
1739
1740         while(!BUTTON_PRESS()) {
1741
1742                 WDT_HIT();
1743
1744                 if(!tracing) {
1745                         DbpString("Trace full");
1746                         break;
1747                 }
1748
1749                 uint8_t read_status = handshakeIclassTag(card_data);
1750                 if(read_status < 2) continue;
1751
1752                 //for now replay captured auth (as cc not updated)
1753                 memcpy(check+5,MAC,4);
1754
1755                 if(sendCmdGetResponseWithRetries(check, sizeof(check),resp, 4, 5))
1756                 {
1757                         Dbprintf("Error: Authentication Fail!");
1758                         continue;
1759                 }
1760
1761                 //first get configuration block (block 1)
1762                 crc = block_crc_LUT[1];
1763                 read[1]=1;
1764                 read[2] = crc >> 8;
1765                 read[3] = crc & 0xff;
1766
1767                 if(sendCmdGetResponseWithRetries(read, sizeof(read),resp, 10, 10))
1768                 {
1769                         Dbprintf("Dump config (block 1) failed");
1770                         continue;
1771                 }
1772
1773                 mem=resp[5];
1774                 memory.k16= (mem & 0x80);
1775                 memory.book= (mem & 0x20);
1776                 memory.k2= (mem & 0x8);
1777                 memory.lockauth= (mem & 0x2);
1778                 memory.keyaccess= (mem & 0x1);
1779
1780                 cardsize = memory.k16 ? 255 : 32;
1781                 WDT_HIT();
1782                 //Set card_data to all zeroes, we'll fill it with data
1783                 memset(card_data,0x0,USB_CMD_DATA_SIZE);
1784                 uint8_t failedRead =0;
1785                 uint32_t stored_data_length =0;
1786                 //then loop around remaining blocks
1787                 for(int block=0; block < cardsize; block++){
1788
1789                         read[1]= block;
1790                         crc = block_crc_LUT[block];
1791                         read[2] = crc >> 8;
1792                         read[3] = crc & 0xff;
1793
1794                         if(!sendCmdGetResponseWithRetries(read, sizeof(read), resp, 10, 10))
1795                         {
1796                                 Dbprintf("     %02x: %02x %02x %02x %02x %02x %02x %02x %02x",
1797                                                  block, resp[0], resp[1], resp[2],
1798                                                 resp[3], resp[4], resp[5],
1799                                                 resp[6], resp[7]);
1800
1801                                 //Fill up the buffer
1802                                 memcpy(card_data+stored_data_length,resp,8);
1803                                 stored_data_length += 8;
1804                                 if(stored_data_length +8 > USB_CMD_DATA_SIZE)
1805                                 {//Time to send this off and start afresh
1806                                         cmd_send(CMD_ACK,
1807                                                          stored_data_length,//data length
1808                                                          failedRead,//Failed blocks?
1809                                                          0,//Not used ATM
1810                                                          card_data, stored_data_length);
1811                                         //reset
1812                                         stored_data_length = 0;
1813                                         failedRead = 0;
1814                                 }
1815
1816                         }else{
1817                                 failedRead = 1;
1818                                 stored_data_length +=8;//Otherwise, data becomes misaligned
1819                                 Dbprintf("Failed to dump block %d", block);
1820                         }
1821                 }
1822
1823                 //Send off any remaining data
1824                 if(stored_data_length > 0)
1825                 {
1826                         cmd_send(CMD_ACK,
1827                                          stored_data_length,//data length
1828                                          failedRead,//Failed blocks?
1829                                          0,//Not used ATM
1830                                          card_data, stored_data_length);
1831                 }
1832                 //If we got here, let's break
1833                 break;
1834         }
1835         //Signal end of transmission
1836         cmd_send(CMD_ACK,
1837                          0,//data length
1838                          0,//Failed blocks?
1839                          0,//Not used ATM
1840                          card_data, 0);
1841
1842         LED_A_OFF();
1843 }
1844
1845 //2. Create Read method (cut-down from above) based off responses from 1.
1846 //   Since we have the MAC could continue to use replay function.
1847 //3. Create Write method
1848 /*
1849 void IClass_iso14443A_write(uint8_t arg0, uint8_t blockNo, uint8_t *data, uint8_t *MAC) {
1850         uint8_t act_all[]     = { 0x0a };
1851         uint8_t identify[]    = { 0x0c };
1852         uint8_t select[]      = { 0x81, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
1853         uint8_t readcheck_cc[]= { 0x88, 0x02 };
1854         uint8_t check[]       = { 0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
1855         uint8_t read[]        = { 0x0c, 0x00, 0x00, 0x00 };
1856         uint8_t write[]       = { 0x87, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
1857
1858     uint16_t crc = 0;
1859
1860         uint8_t* resp = (((uint8_t *)BigBuf) + 3560);
1861
1862         // Reset trace buffer
1863     memset(trace, 0x44, RECV_CMD_OFFSET);
1864         traceLen = 0;
1865
1866         // Setup SSC
1867         FpgaSetupSsc();
1868         // Start from off (no field generated)
1869         // Signal field is off with the appropriate LED
1870         LED_D_OFF();
1871         FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1872         SpinDelay(200);
1873
1874         SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
1875
1876         // Now give it time to spin up.
1877         // Signal field is on with the appropriate LED
1878         FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1879         SpinDelay(200);
1880
1881         LED_A_ON();
1882
1883         for(int i=0;i<1;i++) {
1884
1885                 if(traceLen > TRACE_SIZE) {
1886                         DbpString("Trace full");
1887                         break;
1888                 }
1889
1890                 if (BUTTON_PRESS()) break;
1891
1892                 // Send act_all
1893                 ReaderTransmitIClass(act_all, 1);
1894                 // Card present?
1895                 if(ReaderReceiveIClass(resp)) {
1896                         ReaderTransmitIClass(identify, 1);
1897                         if(ReaderReceiveIClass(resp) == 10) {
1898                                 // Select card
1899                                 memcpy(&select[1],resp,8);
1900                                 ReaderTransmitIClass(select, sizeof(select));
1901
1902                                 if(ReaderReceiveIClass(resp) == 10) {
1903                                         Dbprintf("     Selected CSN: %02x %02x %02x %02x %02x %02x %02x %02x",
1904                                         resp[0], resp[1], resp[2],
1905                                         resp[3], resp[4], resp[5],
1906                                         resp[6], resp[7]);
1907                                 }
1908                                 // Card selected
1909                                 Dbprintf("Readcheck on Sector 2");
1910                                 ReaderTransmitIClass(readcheck_cc, sizeof(readcheck_cc));
1911                                 if(ReaderReceiveIClass(resp) == 8) {
1912                                    Dbprintf("     CC: %02x %02x %02x %02x %02x %02x %02x %02x",
1913                                         resp[0], resp[1], resp[2],
1914                                         resp[3], resp[4], resp[5],
1915                                         resp[6], resp[7]);
1916                                 }else return;
1917                                 Dbprintf("Authenticate");
1918                                 //for now replay captured auth (as cc not updated)
1919                                 memcpy(check+5,MAC,4);
1920                                 Dbprintf("     AA: %02x %02x %02x %02x",
1921                                         check[5], check[6], check[7],check[8]);
1922                                 ReaderTransmitIClass(check, sizeof(check));
1923                                 if(ReaderReceiveIClass(resp) == 4) {
1924                                    Dbprintf("     AR: %02x %02x %02x %02x",
1925                                         resp[0], resp[1], resp[2],resp[3]);
1926                                 }else {
1927                                   Dbprintf("Error: Authentication Fail!");
1928                                   return;
1929                                 }
1930                                 Dbprintf("Write Block");
1931
1932                                 //read configuration for max block number
1933                                 read_success=false;
1934                                 read[1]=1;
1935                                 uint8_t *blockno=&read[1];
1936                                 crc = iclass_crc16((char *)blockno,1);
1937                                 read[2] = crc >> 8;
1938                                 read[3] = crc & 0xff;
1939                                 while(!read_success){
1940                                       ReaderTransmitIClass(read, sizeof(read));
1941                                       if(ReaderReceiveIClass(resp) == 10) {
1942                                          read_success=true;
1943                                          mem=resp[5];
1944                                          memory.k16= (mem & 0x80);
1945                                          memory.book= (mem & 0x20);
1946                                          memory.k2= (mem & 0x8);
1947                                          memory.lockauth= (mem & 0x2);
1948                                          memory.keyaccess= (mem & 0x1);
1949
1950                                       }
1951                                 }
1952                                 if (memory.k16){
1953                                   cardsize=255;
1954                                 }else cardsize=32;
1955                                 //check card_size
1956
1957                                 memcpy(write+1,blockNo,1);
1958                                 memcpy(write+2,data,8);
1959                                 memcpy(write+10,mac,4);
1960                                 while(!send_success){
1961                                   ReaderTransmitIClass(write, sizeof(write));
1962                                   if(ReaderReceiveIClass(resp) == 10) {
1963                                     write_success=true;
1964                                 }
1965                         }//
1966                 }
1967                 WDT_HIT();
1968         }
1969
1970         LED_A_OFF();
1971 }*/