]> git.zerfleddert.de Git - proxmark3-svn/blob - client/cmdcrc.c
projects / proxmark3-svn / blob
? search:


0ca2b8b1e00d816223d991f49d23978dc8f10739
[proxmark3-svn] / 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((unsigned char)str[beginIndex])){
44 ++beginIndex;
45 }
46 if(str[beginIndex] == '\0') {
47 break;
48 }
49 endIndex = beginIndex;
50 while (str[endIndex] && !isspace((unsigned char)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, sizeof(inModel));
438 if (dataLen < 4) return 0;
439 dataLen = param_getstr(Cmd, cmdp++, inHexStr, sizeof(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, sizeof(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 }
Proxmark3 GIT tracking
Impressum, Datenschutz