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 #include <stdlib.h>
  12 #ifdef _WIN32
  13 #  include <io.h>
  14 #  include <fcntl.h>
  15 #  ifndef STDIN_FILENO
  16 #    define STDIN_FILENO 0
  17 #  endif /* STDIN_FILENO */
  18 #endif /* _WIN32 */
  19
  20 #include <stdio.h>
  21 #include <string.h>
  22 //#include <stdlib.h>
  23 //#include <ctype.h>
  24 #include "cmdmain.h"
  25 #include "cmdcrc.h"
  26 #include "reveng/reveng.h"
  27 #include "ui.h"
  28 #include "util.h"
  29
  30 #define MAX_ARGS 20
  31
  32 int uerr(char *msg){
  33         PrintAndLog("%s",msg);
  34         return 0;
  35 }
  36
  37 int split(char *str, char *arr[MAX_ARGS]){
  38     int beginIndex = 0;
  39     int endIndex;
  40     int maxWords = MAX_ARGS;
  41     int wordCnt = 0;
  42
  43     while(1){
  44         while(isspace(str[beginIndex])){
  45             ++beginIndex;
  46         }
  47         if(str[beginIndex] == '\0')
  48             break;
  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("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         //PrintAndLog("argc: %d, %s %s Cmd: %s",argc, argv[0], Cmd2, Cmd);
  74         reveng_main(argc, argv);
  75         for(int i = 0; i < argc; ++i){
  76                 //puts(arr[i]);
  77                 free(argv[i]);
  78         }
  79
  80   return 0;
  81 }
  82
  83 int GetModels(char *Models[], int *count, uint32_t *width){
  84         /* default values */
  85         static model_t model = {
  86                 PZERO,          /* no CRC polynomial, user must specify */
  87                 PZERO,          /* Init = 0 */
  88                 P_BE,           /* RefIn = false, RefOut = false, plus P_RTJUST setting in reveng.h */
  89                 PZERO,          /* XorOut = 0 */
  90                 PZERO,          /* check value unused */
  91                 NULL            /* no model name */
  92         };
  93
  94         int ibperhx = 8;//, obperhx = 8;
  95         int rflags = 0, uflags = 0; /* search and UI flags */
  96         poly_t apoly, crc, qpoly = PZERO, *apolys = NULL, *pptr = NULL, *qptr = NULL;
  97         model_t pset = model, *candmods, *mptr;
  98
  99         /* stdin must be binary */
 100         #ifdef _WIN32
 101                 _setmode(STDIN_FILENO, _O_BINARY);
 102         #endif /* _WIN32 */
 103
 104         SETBMP();
 105
 106         int args = 0, psets, pass;
 107         int Cnt = 0;
 108         if (*width == 0) { //reveng -D
 109                 *count = mcount();
 110                 if(!*count)
 111                         return uerr("no preset models available");
 112
 113                 for(int mode = 0; mode < *count; ++mode) {
 114                         mbynum(&model, mode);
 115                         mcanon(&model);
 116                         size_t size = (model.name && *model.name) ? strlen(model.name) : 6;
 117                         char *tmp = calloc(size+1, sizeof(char));
 118                         if (tmp==NULL)
 119                                 return uerr("out of memory?");
 120
 121                         memcpy(tmp, model.name, size);
 122                         Models[mode] = tmp;
 123                 }
 124                 mfree(&model);
 125         } else { //reveng -s
 126
 127                         if(~model.flags & P_MULXN)
 128                                 return uerr("cannot search for non-Williams compliant models");
 129
 130                         praloc(&model.spoly, *width);
 131                         praloc(&model.init, *width);
 132                         praloc(&model.xorout, *width);
 133                         if(!plen(model.spoly))
 134                                 palloc(&model.spoly, *width);
 135                         else
 136                                 *width = plen(model.spoly);
 137
 138                         /* special case if qpoly is zero, search to end of range */
 139                         if(!ptst(qpoly))
 140                                 rflags &= ~R_HAVEQ;
 141
 142                         /* if endianness not specified, try
 143                          * little-endian then big-endian.
 144                          * NB: crossed-endian algorithms will not be
 145                          * searched.
 146                          */
 147                         /* scan against preset models */
 148                         if(~uflags & C_FORCE) {
 149                                 pass = 0;
 150                                 Cnt = 0;
 151                                 do {
 152                                         psets = mcount();
 153
 154                                         while(psets) {
 155                                                 mbynum(&pset, --psets);
 156
 157                                                 /* skip if different width, or refin or refout don't match */
 158                                                 if(plen(pset.spoly) != *width || (model.flags ^ pset.flags) & (P_REFIN | P_REFOUT))
 159                                                         continue;
 160                                                 /* skip if the preset doesn't match specified parameters */
 161                                                 if(rflags & R_HAVEP && pcmp(&model.spoly, &pset.spoly))
 162                                                         continue;
 163                                                 if(rflags & R_HAVEI && psncmp(&model.init, &pset.init))
 164                                                         continue;
 165                                                 if(rflags & R_HAVEX && psncmp(&model.xorout, &pset.xorout))
 166                                                         continue;
 167
 168                                                 apoly = pclone(pset.xorout);
 169                                                 if(pset.flags & P_REFOUT)
 170                                                         prev(&apoly);
 171                                                 for(qptr = apolys; qptr < pptr; ++qptr) {
 172                                                         crc = pcrc(*qptr, pset.spoly, pset.init, apoly, 0);
 173                                                         if(ptst(crc)) {
 174                                                                 pfree(&crc);
 175                                                                 break;
 176                                                         } else
 177                                                                 pfree(&crc);
 178                                                 }
 179                                                 pfree(&apoly);
 180                                                 if(qptr == pptr) {
 181                                                         /* the selected model solved all arguments */
 182                                                         mcanon(&pset);
 183
 184                                                         size_t size = (pset.name && *pset.name) ? strlen(pset.name) : 6;
 185                                                         //PrintAndLog("Size: %d, %s, count: %d",size,pset.name, Cnt);
 186                                                         char *tmp = calloc(size+1, sizeof(char));
 187
 188                                                         if (tmp == NULL){
 189                                                                 PrintAndLog("out of memory?");
 190                                                                 return 0;
 191                                                         }
 192                                                         memcpy(tmp, pset.name, size);
 193                                                         Models[Cnt++] = tmp;
 194                                                         *count = Cnt;
 195                                                         uflags |= C_RESULT;
 196                                                 }
 197                                         }
 198                                         mfree(&pset);
 199
 200                                         /* toggle refIn/refOut and reflect arguments */
 201                                         if(~rflags & R_HAVERI) {
 202                                                 model.flags ^= P_REFIN | P_REFOUT;
 203                                                 for(qptr = apolys; qptr < pptr; ++qptr)
 204                                                         prevch(qptr, ibperhx);
 205                                         }
 206                                 } while(~rflags & R_HAVERI && ++pass < 2);
 207                         }
 208                         if(uflags & C_RESULT) {
 209                                 for(qptr = apolys; qptr < pptr; ++qptr)
 210                                         pfree(qptr);
 211                         }
 212                         if(!(model.flags & P_REFIN) != !(model.flags & P_REFOUT))
 213                                 return uerr("cannot search for crossed-endian models");
 214
 215                         pass = 0;
 216                         do {
 217                                 mptr = candmods = reveng(&model, qpoly, rflags, args, apolys);
 218                                 if(mptr && plen(mptr->spoly))
 219                                         uflags |= C_RESULT;
 220                                 while(mptr && plen(mptr->spoly)) {
 221                                         mfree(mptr++);
 222                                 }
 223                                 free(candmods);
 224                                 if(~rflags & R_HAVERI) {
 225                                         model.flags ^= P_REFIN | P_REFOUT;
 226                                         for(qptr = apolys; qptr < pptr; ++qptr)
 227                                                 prevch(qptr, ibperhx);
 228                                 }
 229                         } while(~rflags & R_HAVERI && ++pass < 2);
 230                         for(qptr = apolys; qptr < pptr; ++qptr)
 231                                 pfree(qptr);
 232                         free(apolys);
 233                         if(~uflags & C_RESULT)
 234                                 return uerr("no models found");
 235                         mfree(&model);
 236
 237         }
 238         return 1;
 239 }
 240
 241 //-c || -v
 242 //inModel = valid model name string - CRC-8
 243 //inHexStr = input hex string to calculate crc on
 244 //reverse = reverse calc option if true
 245 //endian = {0 = calc default endian input and output, b = big endian input and output, B = big endian output, r = right justified
 246 //          l = little endian input and output, L = little endian output only, t = left justified}
 247 //result = calculated crc hex string
 248 int RunModel(char *inModel, char *inHexStr, bool reverse, char endian, char *result){
 249         /* default values */
 250         static model_t model = {
 251                 PZERO,          // no CRC polynomial, user must specify
 252                 PZERO,          // Init = 0
 253                 P_BE,             // RefIn = false, RefOut = false, plus P_RTJUST setting in reveng.h
 254                 PZERO,          // XorOut = 0
 255                 PZERO,          // check value unused
 256                 NULL              // no model name
 257         };
 258         int ibperhx = 8, obperhx = 8;
 259         int rflags = 0; // search flags
 260         int c;
 261         unsigned long width = 0UL;
 262         poly_t apoly, crc;
 263
 264         char *string;
 265
 266         // stdin must be binary
 267         #ifdef _WIN32
 268                 _setmode(STDIN_FILENO, _O_BINARY);
 269         #endif /* _WIN32 */
 270
 271         SETBMP();
 272         //set model
 273         if(!(c = mbynam(&model, inModel))) {
 274                 PrintAndLog("error: preset model '%s' not found.  Use reveng -D to list presets.", inModel);
 275                 return 0;
 276         }
 277         if(c < 0)
 278                 return uerr("no preset models available");
 279
 280         // must set width so that parameter to -ipx is not zeroed
 281         width = plen(model.spoly);
 282         rflags |= R_HAVEP | R_HAVEI | R_HAVERI | R_HAVERO | R_HAVEX;
 283
 284         //set flags
 285         switch (endian) {
 286                 case 'b': /* b  big-endian (RefIn = false, RefOut = false ) */
 287                         model.flags &= ~P_REFIN;
 288                         rflags |= R_HAVERI;
 289                         /* fall through: */
 290                 case 'B': /* B  big-endian output (RefOut = false) */
 291                         model.flags &= ~P_REFOUT;
 292                         rflags |= R_HAVERO;
 293                         mnovel(&model);
 294                         /* fall through: */
 295                 case 'r': /* r  right-justified */
 296                         model.flags |= P_RTJUST;
 297                         break;
 298                 case 'l': /* l  little-endian input and output */
 299                         model.flags |= P_REFIN;
 300                         rflags |= R_HAVERI;
 301                         /* fall through: */
 302                 case 'L': /* L  little-endian output */
 303                         model.flags |= P_REFOUT;
 304                         rflags |= R_HAVERO;
 305                         mnovel(&model);
 306                         /* fall through: */
 307                 case 't': /* t  left-justified */
 308                         model.flags &= ~P_RTJUST;
 309                         break;
 310         }
 311
 312         mcanon(&model);
 313
 314         if (reverse) {
 315                 // v  calculate reversed CRC
 316                 /* Distinct from the -V switch as this causes
 317                  * the arguments and output to be reversed as well.
 318                  */
 319                 // reciprocate Poly
 320                 prcp(&model.spoly);
 321
 322                 /* mrev() does:
 323                  *   if(refout) prev(init); else prev(xorout);
 324                  * but here the entire argument polynomial is
 325                  * reflected, not just the characters, so RefIn
 326                  * and RefOut are not inverted as with -V.
 327                  * Consequently Init is the mirror image of the
 328                  * one resulting from -V, and so we have:
 329                  */
 330                 if(~model.flags & P_REFOUT) {
 331                         prev(&model.init);
 332                         prev(&model.xorout);
 333                 }
 334
 335                 // swap init and xorout
 336                 apoly = model.init;
 337                 model.init = model.xorout;
 338                 model.xorout = apoly;
 339         }
 340         // c  calculate CRC
 341
 342         /* in the Williams model, xorout is applied after the refout stage.
 343          * as refout is part of ptostr(), we reverse xorout here.
 344          */
 345         if(model.flags & P_REFOUT)
 346                 prev(&model.xorout);
 347
 348         apoly = strtop(inHexStr, model.flags, ibperhx);
 349
 350         if(reverse)
 351                 prev(&apoly);
 352
 353         crc = pcrc(apoly, model.spoly, model.init, model.xorout, model.flags);
 354
 355         if(reverse)
 356                 prev(&crc);
 357
 358         string = ptostr(crc, model.flags, obperhx);
 359         for (int i = 0; i < 50; i++){
 360                 result[i] = string[i];
 361                 if (result[i]==0) break;
 362         }
 363         free(string);
 364         pfree(&crc);
 365         pfree(&apoly);
 366         return 1;
 367 }