cvs.zerfleddert.de Git - proxmark3-svn/blob - client/cmdcrc.c

   1 //-----------------------------------------------------------------------------
   2 // Copyright (C) 2015 iceman <iceman at iuse.se>
   3 //
   4 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   5 // at your option, any later version. See the LICENSE.txt file for the text of
   6 // the license.
   7 //-----------------------------------------------------------------------------
   8 // CRC Calculations from the software reveng commands
   9 //-----------------------------------------------------------------------------
  10
  11 #ifdef _WIN32
  12 #  include <io.h>
  13 #  include <fcntl.h>
  14 #  ifndef STDIN_FILENO
  15 #    define STDIN_FILENO 0
  16 #  endif /* STDIN_FILENO */
  17 #endif /* _WIN32 */
  18
  19 #include <stdio.h>
  20 #include <string.h>
  21 #include <stdlib.h>
  22 #include <ctype.h>
  23 #include "cmdmain.h"
  24 #include "cmdcrc.h"
  25 #include "reveng/reveng.h"
  26 #include "ui.h"
  27 #include "util.h"
  28
  29 #define MAX_ARGS 20
  30
  31 int uerr(char *msg){
  32         PrintAndLog("%s",msg);
  33         return 0;
  34 }
  35
  36 int split(char *str, char *arr[MAX_ARGS]){
  37         int beginIndex = 0;
  38         int endIndex;
  39         int maxWords = MAX_ARGS;
  40         int wordCnt = 0;
  41
  42         while(1){
  43                 while(isspace(str[beginIndex])){
  44                         ++beginIndex;
  45                 }
  46                 if(str[beginIndex] == '\0') {
  47                         break;
  48                 }
  49                 endIndex = beginIndex;
  50                 while (str[endIndex] && !isspace(str[endIndex])){
  51                         ++endIndex;
  52                 }
  53                 int len = endIndex - beginIndex;
  54                 char *tmp = calloc(len + 1, sizeof(char));
  55                 memcpy(tmp, &str[beginIndex], len);
  56                 arr[wordCnt++] = tmp;
  57                 //PrintAndLog("DEBUG cnt: %d, %s",wordCnt-1, arr[wordCnt-1]);
  58                 beginIndex = endIndex;
  59                 if (wordCnt == maxWords)
  60                         break;
  61         }
  62         return wordCnt;
  63 }
  64
  65 int CmdCrc(const char *Cmd)
  66 {
  67         char name[] = {"reveng "};
  68         char Cmd2[50 + 7];
  69         memcpy(Cmd2, name, 7);
  70         memcpy(Cmd2 + 7, Cmd, 50);
  71         char *argv[MAX_ARGS];
  72         int argc = split(Cmd2, argv);
  73
  74         if (argc == 3 && memcmp(argv[1],"-g",2)==0) {
  75                 CmdrevengSearch(argv[2]);
  76         } else {
  77                 reveng_main(argc, argv);
  78         }
  79         //PrintAndLog("DEBUG argc: %d, %s %s Cmd: %s",argc, argv[0], Cmd2, Cmd);
  80         for(int i = 0; i < argc; ++i){
  81                 free(argv[i]);
  82         }
  83
  84         return 0;
  85 }
  86
  87 //returns array of model names and the count of models returning
  88 //  as well as a width array for the width of each model
  89 int GetModels(char *Models[], int *count, uint8_t *width){
  90         /* default values */
  91         static model_t model = {
  92                 PZERO,          /* no CRC polynomial, user must specify */
  93                 PZERO,          /* Init = 0 */
  94                 P_BE,           /* RefIn = false, RefOut = false, plus P_RTJUST setting in reveng.h */
  95                 PZERO,          /* XorOut = 0 */
  96                 PZERO,          /* check value unused */
  97                 NULL            /* no model name */
  98         };
  99
 100         int ibperhx = 8;//, obperhx = 8;
 101         int rflags = 0, uflags = 0; /* search and UI flags */
 102         poly_t apoly, crc, qpoly = PZERO, *apolys = NULL, *pptr = NULL, *qptr = NULL;
 103         model_t pset = model, *candmods, *mptr;
 104
 105         /* stdin must be binary */
 106         #ifdef _WIN32
 107                 _setmode(STDIN_FILENO, _O_BINARY);
 108         #endif /* _WIN32 */
 109
 110         SETBMP();
 111
 112         int args = 0, psets, pass;
 113         int Cnt = 0;
 114         if (width[0] == 0) { //reveng -D
 115                 *count = mcount();
 116                 if(!*count)
 117                         return uerr("no preset models available");
 118
 119                 for(int mode = 0; mode < *count; ++mode) {
 120                         mbynum(&model, mode);
 121                         mcanon(&model);
 122                         size_t size = (model.name && *model.name) ? strlen(model.name) : 6;
 123                         char *tmp = calloc(size+1, sizeof(char));
 124                         if (tmp==NULL)
 125                                 return uerr("out of memory?");
 126
 127                         memcpy(tmp, model.name, size);
 128                         Models[mode] = tmp;
 129                         width[mode] = plen(model.spoly);
 130                 }
 131                 mfree(&model);
 132         } else { //reveng -s
 133
 134                 if(~model.flags & P_MULXN)
 135                         return uerr("cannot search for non-Williams compliant models");
 136
 137                 praloc(&model.spoly, (unsigned long)width[0]);
 138                 praloc(&model.init, (unsigned long)width[0]);
 139                 praloc(&model.xorout, (unsigned long)width[0]);
 140                 if(!plen(model.spoly))
 141                         palloc(&model.spoly, (unsigned long)width[0]);
 142                 else
 143                         width[0] = (uint8_t)plen(model.spoly);
 144
 145                 /* special case if qpoly is zero, search to end of range */
 146                 if(!ptst(qpoly))
 147                         rflags &= ~R_HAVEQ;
 148
 149
 150                 /* not going to be sending additional args at this time (maybe future?)
 151
 152                 // allocate argument array
 153                 args = argc - optind;
 154                 if(!(apolys = malloc(args * sizeof(poly_t))))
 155                         return uerr("cannot allocate memory for argument list");
 156
 157                 for(pptr = apolys; optind < argc; ++optind) {
 158                         if(uflags & C_INFILE)
 159                                 *pptr++ = rdpoly(argv[optind], model.flags, ibperhx);
 160                         else
 161                                 *pptr++ = strtop(argv[optind], model.flags, ibperhx);
 162                 }
 163                 // exit value of pptr is used hereafter!
 164
 165                 */
 166
 167                 /* if endianness not specified, try
 168                  * little-endian then big-endian.
 169                  * NB: crossed-endian algorithms will not be
 170                  * searched.
 171                  */
 172                 /* scan against preset models */
 173                 if(~uflags & C_FORCE) {
 174                         pass = 0;
 175                         Cnt = 0;
 176                         do {
 177                                 psets = mcount();
 178                                 //PrintAndLog("psets: %d",psets);
 179                                 while(psets) {
 180                                         mbynum(&pset, --psets);
 181
 182                                         /* skip if different width, or refin or refout don't match */
 183                                         if(plen(pset.spoly) != width[0] || (model.flags ^ pset.flags) & (P_REFIN | P_REFOUT))
 184                                                 continue;
 185                                         /* skip if the preset doesn't match specified parameters */
 186                                         if(rflags & R_HAVEP && pcmp(&model.spoly, &pset.spoly))
 187                                                 continue;
 188                                         if(rflags & R_HAVEI && psncmp(&model.init, &pset.init))
 189                                                 continue;
 190                                         if(rflags & R_HAVEX && psncmp(&model.xorout, &pset.xorout))
 191                                                 continue;
 192
 193                                         //for additional args (not used yet, maybe future?)
 194                                         apoly = pclone(pset.xorout);
 195                                         if(pset.flags & P_REFOUT)
 196                                                 prev(&apoly);
 197
 198                                         for(qptr = apolys; qptr < pptr; ++qptr) {
 199                                                 crc = pcrc(*qptr, pset.spoly, pset.init, apoly, 0);
 200                                                 if(ptst(crc)) {
 201                                                         pfree(&crc);
 202                                                         break;
 203                                                 } else
 204                                                         pfree(&crc);
 205                                         }
 206                                         pfree(&apoly);
 207                                         if(qptr == pptr) {
 208
 209                                                 /* the selected model solved all arguments */
 210
 211                                                 mcanon(&pset);
 212
 213                                                 size_t size = (pset.name && *pset.name) ? strlen(pset.name) : 6;
 214                                                 //PrintAndLog("Size: %d, %s, count: %d",size,pset.name, Cnt);
 215                                                 char *tmp = calloc(size+1, sizeof(char));
 216                                                 if (tmp==NULL){
 217                                                         PrintAndLog("out of memory?");
 218                                                         return 0;
 219                                                 }
 220                                                 width[Cnt] = width[0];
 221                                                 memcpy(tmp, pset.name, size);
 222                                                 Models[Cnt++] = tmp;
 223                                                 *count = Cnt;
 224                                                 uflags |= C_RESULT;
 225                                         }
 226                                 }
 227                                 mfree(&pset);
 228
 229                                 /* toggle refIn/refOut and reflect arguments */
 230                                 if(~rflags & R_HAVERI) {
 231                                         model.flags ^= P_REFIN | P_REFOUT;
 232                                         for(qptr = apolys; qptr < pptr; ++qptr)
 233                                                 prevch(qptr, ibperhx);
 234                                 }
 235                         } while(~rflags & R_HAVERI && ++pass < 2);
 236                 }
 237                 //got everything now free the memory...
 238
 239                 if(uflags & C_RESULT) {
 240                         for(qptr = apolys; qptr < pptr; ++qptr)
 241                                 pfree(qptr);
 242                 }
 243                 if(!(model.flags & P_REFIN) != !(model.flags & P_REFOUT))
 244                         return uerr("cannot search for crossed-endian models");
 245
 246                 pass = 0;
 247                 do {
 248                         mptr = candmods = reveng(&model, qpoly, rflags, args, apolys);
 249                         if(mptr && plen(mptr->spoly))
 250                                 uflags |= C_RESULT;
 251                         while(mptr && plen(mptr->spoly)) {
 252                                 mfree(mptr++);
 253                         }
 254                         free(candmods);
 255                         if(~rflags & R_HAVERI) {
 256                                 model.flags ^= P_REFIN | P_REFOUT;
 257                                 for(qptr = apolys; qptr < pptr; ++qptr)
 258                                         prevch(qptr, ibperhx);
 259                         }
 260                 } while(~rflags & R_HAVERI && ++pass < 2);
 261                 for(qptr = apolys; qptr < pptr; ++qptr)
 262                         pfree(qptr);
 263                 free(apolys);
 264                 if(~uflags & C_RESULT)
 265                         return uerr("no models found");
 266                 mfree(&model);
 267         }
 268         return 1;
 269 }
 270
 271 //test call to GetModels
 272 int CmdrevengTest(const char *Cmd){
 273         char *Models[80];
 274         int count = 0;
 275         uint8_t widtharr[80] = {0};
 276         uint8_t width = 0;
 277         width = param_get8(Cmd, 0);
 278         //PrintAndLog("width: %d",width);
 279         if (width > 89)
 280                 return uerr("Width cannot exceed 89");
 281
 282         widtharr[0] = width;
 283         int ans = GetModels(Models, &count, widtharr);
 284         if (!ans) return 0;
 285
 286         PrintAndLog("Count: %d",count);
 287         for (int i = 0; i < count; i++){
 288                 PrintAndLog("Model %d: %s, width: %d",i,Models[i], widtharr[i]);
 289                 free(Models[i]);
 290         }
 291         return 1;
 292 }
 293
 294 //-c || -v
 295 //inModel = valid model name string - CRC-8
 296 //inHexStr = input hex string to calculate crc on
 297 //reverse = reverse calc option if true
 298 //endian = {0 = calc default endian input and output, b = big endian input and output, B = big endian output, r = right justified
 299 //          l = little endian input and output, L = little endian output only, t = left justified}
 300 //result = calculated crc hex string
 301 int RunModel(char *inModel, char *inHexStr, bool reverse, char endian, char *result){
 302         /* default values */
 303         static model_t model = {
 304                 PZERO,          // no CRC polynomial, user must specify
 305                 PZERO,          // Init = 0
 306                 P_BE,             // RefIn = false, RefOut = false, plus P_RTJUST setting in reveng.h
 307                 PZERO,          // XorOut = 0
 308                 PZERO,          // check value unused
 309                 NULL              // no model name
 310         };
 311         int ibperhx = 8, obperhx = 8;
 312         int rflags = 0; // search flags
 313         int c;
 314         //unsigned long width;
 315         poly_t apoly, crc;
 316
 317         char *string;
 318
 319         // stdin must be binary
 320         #ifdef _WIN32
 321                 _setmode(STDIN_FILENO, _O_BINARY);
 322         #endif /* _WIN32 */
 323
 324         SETBMP();
 325         //set model
 326         if(!(c = mbynam(&model, inModel))) {
 327                 fprintf(stderr,"error: preset model '%s' not found.  Use reveng -D to list presets.\n", inModel);
 328                 return 0;
 329         }
 330         if(c < 0)
 331                 return uerr("no preset models available");
 332
 333         // must set width so that parameter to -ipx is not zeroed
 334         //width = plen(model.spoly);
 335         rflags |= R_HAVEP | R_HAVEI | R_HAVERI | R_HAVERO | R_HAVEX;
 336
 337         //set flags
 338         switch (endian) {
 339                 case 'b': /* b  big-endian (RefIn = false, RefOut = false ) */
 340                         model.flags &= ~P_REFIN;
 341                         rflags |= R_HAVERI;
 342                         /* fall through: */
 343                 case 'B': /* B  big-endian output (RefOut = false) */
 344                         model.flags &= ~P_REFOUT;
 345                         rflags |= R_HAVERO;
 346                         mnovel(&model);
 347                         /* fall through: */
 348                 case 'r': /* r  right-justified */
 349                         model.flags |= P_RTJUST;
 350                         break;
 351                 case 'l': /* l  little-endian input and output */
 352                         model.flags |= P_REFIN;
 353                         rflags |= R_HAVERI;
 354                         /* fall through: */
 355                 case 'L': /* L  little-endian output */
 356                         model.flags |= P_REFOUT;
 357                         rflags |= R_HAVERO;
 358                         mnovel(&model);
 359                         /* fall through: */
 360                 case 't': /* t  left-justified */
 361                         model.flags &= ~P_RTJUST;
 362                         break;
 363         }
 364
 365         mcanon(&model);
 366
 367         if (reverse) {
 368                 // v  calculate reversed CRC
 369                 /* Distinct from the -V switch as this causes
 370                  * the arguments and output to be reversed as well.
 371                  */
 372                 // reciprocate Poly
 373                 prcp(&model.spoly);
 374
 375                 /* mrev() does:
 376                  *   if(refout) prev(init); else prev(xorout);
 377                  * but here the entire argument polynomial is
 378                  * reflected, not just the characters, so RefIn
 379                  * and RefOut are not inverted as with -V.
 380                  * Consequently Init is the mirror image of the
 381                  * one resulting from -V, and so we have:
 382                  */
 383                 if(~model.flags & P_REFOUT) {
 384                         prev(&model.init);
 385                         prev(&model.xorout);
 386                 }
 387
 388                 // swap init and xorout
 389                 apoly = model.init;
 390                 model.init = model.xorout;
 391                 model.xorout = apoly;
 392         }
 393         // c  calculate CRC
 394
 395         // validate inputs
 396         /* if(plen(model.spoly) == 0) {
 397          *      fprintf(stderr,"%s: no polynomial specified for -%c (add -w WIDTH -p POLY)\n", myname, mode);
 398          *      exit(EXIT_FAILURE);
 399          * }
 400          */
 401
 402         /* in the Williams model, xorout is applied after the refout stage.
 403          * as refout is part of ptostr(), we reverse xorout here.
 404          */
 405         if(model.flags & P_REFOUT)
 406                 prev(&model.xorout);
 407
 408         apoly = strtop(inHexStr, model.flags, ibperhx);
 409
 410         if(reverse)
 411                 prev(&apoly);
 412
 413         crc = pcrc(apoly, model.spoly, model.init, model.xorout, model.flags);
 414
 415         if(reverse)
 416                 prev(&crc);
 417
 418         string = ptostr(crc, model.flags, obperhx);
 419         for (int i = 0; i < 50; i++){
 420                 result[i] = string[i];
 421                 if (result[i]==0) break;
 422         }
 423         free(string);
 424         pfree(&crc);
 425         pfree(&apoly);
 426         return 1;
 427 }
 428
 429 //test call to RunModel
 430 int CmdrevengTestC(const char *Cmd){
 431         int cmdp = 0;
 432         char inModel[30] = {0x00};
 433         char inHexStr[30] = {0x00};
 434         char result[30];
 435         int dataLen;
 436         char endian = 0;
 437         dataLen = param_getstr(Cmd, cmdp++, inModel);
 438         if (dataLen < 4) return 0;
 439         dataLen = param_getstr(Cmd, cmdp++, inHexStr);
 440         if (dataLen < 4) return 0;
 441         bool reverse = (param_get8(Cmd, cmdp++)) ? true : false;
 442         endian = param_getchar(Cmd, cmdp++);
 443
 444         //PrintAndLog("mod: %s, hex: %s, rev %d", inModel, inHexStr, reverse);
 445         int ans = RunModel(inModel, inHexStr, reverse, endian, result);
 446         if (!ans) return 0;
 447
 448         PrintAndLog("Result: %s",result);
 449         return 1;
 450 }
 451
 452 //returns a calloced string (needs to be freed)
 453 char *SwapEndianStr(const char *inStr, const size_t len, const uint8_t blockSize){
 454         char *tmp = calloc(len+1, sizeof(char));
 455         for (uint8_t block=0; block < (uint8_t)(len/blockSize); block++){
 456                 for (size_t i = 0; i < blockSize; i+=2){
 457                         tmp[i+(blockSize*block)] = inStr[(blockSize-1-i-1)+(blockSize*block)];
 458                         tmp[i+(blockSize*block)+1] = inStr[(blockSize-1-i)+(blockSize*block)];
 459                 }
 460         }
 461         return tmp;
 462 }
 463
 464 // takes hex string in and searches for a matching result (hex string must include checksum)
 465 int CmdrevengSearch(const char *Cmd){
 466         char inHexStr[50] = {0x00};
 467         int dataLen = param_getstr(Cmd, 0, inHexStr);
 468         if (dataLen < 4) return 0;
 469
 470         char *Models[80];
 471         int count = 0;
 472         uint8_t width[80];
 473         width[0] = 0;
 474         uint8_t crcChars = 0;
 475         char result[30];
 476         char revResult[30];
 477         int ans = GetModels(Models, &count, width);
 478         bool found = false;
 479         if (!ans) return 0;
 480
 481         // try each model and get result
 482         for (int i = 0; i < count; i++){
 483                 /*if (found) {
 484                         free(Models[i]);
 485                         continue;
 486                 }*/
 487                 // round up to # of characters in this model's crc
 488                 crcChars = ((width[i]+7)/8)*2;
 489                 // can't test a model that has more crc digits than our data
 490                 if (crcChars >= dataLen)
 491                         continue;
 492                 memset(result, 0, 30);
 493                 char *inCRC = calloc(crcChars+1, sizeof(char));
 494                 memcpy(inCRC, inHexStr+(dataLen-crcChars), crcChars);
 495
 496                 char *outHex = calloc(dataLen-crcChars+1, sizeof(char));
 497                 memcpy(outHex, inHexStr, dataLen-crcChars);
 498
 499                 //PrintAndLog("DEBUG: dataLen: %d, crcChars: %d, Model: %s, CRC: %s, width: %d, outHex: %s",dataLen, crcChars, Models[i], inCRC, width[i], outHex);
 500                 ans = RunModel(Models[i], outHex, false, 0, result);
 501                 if (ans) {
 502                         //test for match
 503                         if (memcmp(result, inCRC, crcChars)==0){
 504                                 PrintAndLog("\nFound a possible match!\nModel: %s\nValue: %s\n",Models[i], result);
 505                                 //optional - stop searching if found...
 506                                 found = true;
 507                         } else {
 508                                 if (crcChars > 2){
 509                                         char *swapEndian = SwapEndianStr(result, crcChars, crcChars);
 510                                         if (memcmp(swapEndian, inCRC, crcChars)==0){
 511                                                 PrintAndLog("\nFound a possible match!\nModel: %s\nValue EndianSwapped: %s\n",Models[i], swapEndian);
 512                                                 //optional - stop searching if found...
 513                                                 found = true;
 514                                         }
 515                                         free(swapEndian);
 516                                 }
 517                         }
 518                 }
 519
 520                 //if (!found){
 521                         ans = RunModel(Models[i], outHex, true, 0, revResult);
 522                         if (ans) {
 523                                 //test for match
 524                                 if (memcmp(revResult, inCRC, crcChars)==0){
 525                                         PrintAndLog("\nFound a possible match!\nModel Reversed: %s\nValue: %s\n",Models[i], revResult);
 526                                         //optional - stop searching if found...
 527                                         found = true;
 528                                 } else {
 529                                         if (crcChars > 2){
 530                                                 char *swapEndian = SwapEndianStr(revResult, crcChars, crcChars);
 531                                                 if (memcmp(swapEndian, inCRC, crcChars)==0){
 532                                                         PrintAndLog("\nFound a possible match!\nModel Reversed: %s\nValue EndianSwapped: %s\n",Models[i], swapEndian);
 533                                                         //optional - stop searching if found...
 534                                                         found = true;
 535                                                 }
 536                                                 free(swapEndian);
 537                                         }
 538                                 }
 539                         }
 540                 //}
 541                 free(inCRC);
 542                 free(outHex);
 543                 free(Models[i]);
 544         }
 545         if (!found) PrintAndLog("\nNo matches found\n");
 546         return 1;
 547 }