git.zerfleddert.de Git - proxmark3-svn/blob

1 //-----------------------------------------------------------------------------

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 //-----------------------------------------------------------------------------

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 */

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"

29 #define MAX_ARGS 20

 int uerr(char *msg){

         PrintAndLog("%s",msg);

33 return 0;

34 }

 int split(char *str, char *arr[MAX_ARGS]){

37 int beginIndex = 0;

38 int endIndex;

39 int maxWords = MAX_ARGS;

40 int wordCnt = 0;

42 while(1){

                 while(isspace(str[beginIndex])){

44 ++beginIndex;

45 }

                 if(str[beginIndex] == '\0') {

47 break;

48 }

49 endIndex = beginIndex;

                 while (str[endIndex] && !isspace(str[endIndex])){

51 ++endIndex;

52 }

53 int len = endIndex - beginIndex;

                 char *tmp = calloc(len + 1, sizeof(char));

                 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 }

 int CmdCrc(const char *Cmd)

66 {

67 char name[] = {"reveng "};

         char Cmd2[50 + 7];

         memcpy(Cmd2, name, 7);

         memcpy(Cmd2 + 7, Cmd, 50);

71 char *argv[MAX_ARGS];

         int argc = split(Cmd2, argv);

         if (argc == 3 && memcmp(argv[1],"-g",2)==0) {

                 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);

         for(int i = 0; i < argc; ++i){

81 free(argv[i]);

82 }

84 return 0;

85 }

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

 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 };

         int ibperhx = 8;//, obperhx = 8;

         int rflags = 0, uflags = 0; /* search and UI flags */

         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

         int args = 0, psets, pass;

113 int Cnt = 0;

         if (width[0] == 0) { //reveng -D

115 *count = mcount();

116 if(!*count)

                         return uerr("no preset models available");

118

                 for(int mode = 0; mode < *count; ++mode) {

120 mbynum(&model, mode);

121 mcanon(&model);

                         size_t size = (model.name && *model.name) ? strlen(model.name) : 6;

                         char *tmp = calloc(size+1, sizeof(char));

124 if (tmp==NULL)

                                 return uerr("out of memory?");

126

                         memcpy(tmp, model.name, size);

128 Models[mode] = tmp;

                         width[mode] = plen(model.spoly);

130 }

131 mfree(&model);

132 } else { //reveng -s

133

                 if(~model.flags & P_MULXN)

                         return uerr("cannot search for non-Williams compliant models");

136

                 praloc(&model.spoly, (unsigned long)width[0]);

                 praloc(&model.init, (unsigned long)width[0]);

                 praloc(&model.xorout, (unsigned long)width[0]);

                 if(!plen(model.spoly))

                         palloc(&model.spoly, (unsigned long)width[0]);

142 else

                         width[0] = (uint8_t)plen(model.spoly);

144

145 /* special case if qpoly is zero, search to end of range */

                 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 */

                                         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 */

                                         if(rflags & R_HAVEP && pcmp(&model.spoly, &pset.spoly))

187 continue;

                                         if(rflags & R_HAVEI && psncmp(&model.init, &pset.init))

189 continue;

                                         if(rflags & R_HAVEX && psncmp(&model.xorout, &pset.xorout))

191 continue;

192

193 //for additional args (not used yet, maybe future?)

                                         apoly = pclone(pset.xorout);

                                         if(pset.flags & P_REFOUT)

196 prev(&apoly);

197

                                         for(qptr = apolys; qptr < pptr; ++qptr) {

                                                 crc = pcrc(*qptr, pset.spoly, pset.init, apoly, 0);

                                                 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

                                                 size_t size = (pset.name && *pset.name) ? strlen(pset.name) : 6;

214 //PrintAndLog("Size: %d, %s, count: %d",size,pset.name, Cnt);

                                                 char *tmp = calloc(size+1, sizeof(char));

216 if (tmp==NULL){

217 PrintAndLog("out of memory?");

218 return 0;

219 }

                                                 width[Cnt] = width[0];

                                                 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;

                                         for(qptr = apolys; qptr < pptr; ++qptr)

233 prevch(qptr, ibperhx);

234 }

                         } while(~rflags & R_HAVERI && ++pass < 2);

236 }

237 //got everything now free the memory...

238

239 if(uflags & C_RESULT) {

                         for(qptr = apolys; qptr < pptr; ++qptr)

241 pfree(qptr);

242 }

                 if(!(model.flags & P_REFIN) != !(model.flags & P_REFOUT))

                         return uerr("cannot search for crossed-endian models");

245

246 pass = 0;

247 do {

                         mptr = candmods = reveng(&model, qpoly, rflags, args, apolys);

                         if(mptr && plen(mptr->spoly))

250 uflags |= C_RESULT;

                         while(mptr && plen(mptr->spoly)) {

252 mfree(mptr++);

253 }

254 free(candmods);

255 if(~rflags & R_HAVERI) {

256 model.flags ^= P_REFIN | P_REFOUT;

                                 for(qptr = apolys; qptr < pptr; ++qptr)

258 prevch(qptr, ibperhx);

259 }

                 } while(~rflags & R_HAVERI && ++pass < 2);

                 for(qptr = apolys; qptr < pptr; ++qptr)

262 pfree(qptr);

263 free(apolys);

264 if(~uflags & C_RESULT)

                         return uerr("no models found");

266 mfree(&model);

267 }

268 return 1;

269 }

270

271 //test call to GetModels

 int CmdrevengTest(const char *Cmd){

         char *Models[80];

274 int count = 0;

         uint8_t widtharr[80] = {0};

276 uint8_t width = 0;

         width = param_get8(Cmd, 0);

278 //PrintAndLog("width: %d",width);

         if (width > 89)

                 return uerr("Width cannot exceed 89");

281

282 widtharr[0] = width;

         int ans = GetModels(Models, &count, widtharr);

         if (!ans) return 0;

285

         PrintAndLog("Count: %d",count);

         for (int i = 0; i < count; i++){

                 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

 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 };

         int ibperhx = 8, obperhx = 8;

         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

         if(!(c = mbynam(&model, inModel))) {

                 fprintf(stderr,"error: preset model '%s' not found.  Use reveng -D to list presets.\n", inModel);

328 return 0;

329 }

         if(c < 0)

                 return uerr("no preset models available");

332

333 // must set width so that parameter to -ipx is not zeroed

334 //width = plen(model.spoly);

         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 */

                 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 */

         if(model.flags & P_REFOUT)

406 prev(&model.xorout);

407

         apoly = strtop(inHexStr, model.flags, ibperhx);

409

410 if(reverse)

411 prev(&apoly);

412

         crc = pcrc(apoly, model.spoly, model.init, model.xorout, model.flags);

414

415 if(reverse)

416 prev(&crc);

417

         string = ptostr(crc, model.flags, obperhx);

         for (int i = 0; i < 50; i++){

420 result[i] = string[i];

                 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

 int CmdrevengTestC(const char *Cmd){

431 int cmdp = 0;

         char inModel[30] = {0x00};

         char inHexStr[30] = {0x00};

434 char result[30];

435 int dataLen;

436 char endian = 0;

         dataLen = param_getstr(Cmd, cmdp++, inModel);

         if (dataLen < 4) return 0;

         dataLen = param_getstr(Cmd, cmdp++, inHexStr);

         if (dataLen < 4) return 0;

         bool reverse = (param_get8(Cmd, cmdp++)) ? true : false;

         endian = param_getchar(Cmd, cmdp++); 

443

444 //PrintAndLog("mod: %s, hex: %s, rev %d", inModel, inHexStr, reverse);

         int ans = RunModel(inModel, inHexStr, reverse, endian, result);

         if (!ans) return 0;

447

         PrintAndLog("Result: %s",result);

449 return 1;

450 }

451

452 //returns a calloced string (needs to be freed)

 char *SwapEndianStr(const char *inStr, const size_t len, const uint8_t blockSize){

         char *tmp = calloc(len+1, sizeof(char));

         for (uint8_t block=0; block < (uint8_t)(len/blockSize); block++){

                 for (size_t i = 0; i < blockSize; i+=2){

                         tmp[i+(blockSize*block)] = inStr[(blockSize-1-i-1)+(blockSize*block)];

                         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)

 int CmdrevengSearch(const char *Cmd){

         char inHexStr[50] = {0x00};

         int dataLen = param_getstr(Cmd, 0, inHexStr);

         if (dataLen < 4) return 0;

469

         char *Models[80];

471 int count = 0;

472 uint8_t width[80];

         width[0] = 0;

474 uint8_t crcChars = 0;

475 char result[30];

476 char revResult[30];

         int ans = GetModels(Models, &count, width);

478 bool found = false;

         if (!ans) return 0;

480

481 // try each model and get result

         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

                 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;

                 memset(result, 0, 30);

                 char *inCRC = calloc(crcChars+1, sizeof(char));

                 memcpy(inCRC, inHexStr+(dataLen-crcChars), crcChars);

495

                 char *outHex = calloc(dataLen-crcChars+1, sizeof(char));

                 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);

                 ans = RunModel(Models[i], outHex, false, 0, result);

501 if (ans) {

502 //test for match

                         if (memcmp(result, inCRC, crcChars)==0){

                                 PrintAndLog("\nFound a possible match!\nModel: %s\nValue: %s\n",Models[i], result);

505 //optional - stop searching if found...

506 found = true;

507 } else {

                                 if (crcChars > 2){

                                         char *swapEndian = SwapEndianStr(result, crcChars, crcChars);

                                         if (memcmp(swapEndian, inCRC, crcChars)==0){

                                                 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){

                         ans = RunModel(Models[i], outHex, true, 0, revResult);

522 if (ans) {

523 //test for match

                                 if (memcmp(revResult, inCRC, crcChars)==0){

                                         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 {

                                         if (crcChars > 2){

                                                 char *swapEndian = SwapEndianStr(revResult, crcChars, crcChars);

                                                 if (memcmp(swapEndian, inCRC, crcChars)==0){

                                                         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 }

         if (!found) PrintAndLog("\nNo matches found\n");

546 return 1;

547 }