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Merge pull request #282 from Proxmark/graphwork2
[proxmark3-svn] / client / mifarehost.c
1 // Merlok, 2011, 2012
2 // people from mifare@nethemba.com, 2010
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 // mifare commands
9 //-----------------------------------------------------------------------------
10
11 #include "mifarehost.h"
12
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 #include <pthread.h>
17
18 #include "crapto1/crapto1.h"
19 #include "proxmark3.h"
20 #include "usb_cmd.h"
21 #include "cmdmain.h"
22 #include "ui.h"
23 #include "util.h"
24 #include "iso14443crc.h"
25
26 // mifare tracer flags used in mfTraceDecode()
27 #define TRACE_IDLE 0x00
28 #define TRACE_AUTH1 0x01
29 #define TRACE_AUTH2 0x02
30 #define TRACE_AUTH_OK 0x03
31 #define TRACE_READ_DATA 0x04
32 #define TRACE_WRITE_OK 0x05
33 #define TRACE_WRITE_DATA 0x06
34 #define TRACE_ERROR 0xFF
35
36
37 static int compare_uint64(const void *a, const void *b) {
38 // didn't work: (the result is truncated to 32 bits)
39 //return (*(int64_t*)b - *(int64_t*)a);
40
41 // better:
42 if (*(uint64_t*)b == *(uint64_t*)a) return 0;
43 else if (*(uint64_t*)b < *(uint64_t*)a) return 1;
44 else return -1;
45 }
46
47
48 // create the intersection (common members) of two sorted lists. Lists are terminated by -1. Result will be in list1. Number of elements is returned.
49 static uint32_t intersection(uint64_t *list1, uint64_t *list2)
50 {
51 if (list1 == NULL || list2 == NULL) {
52 return 0;
53 }
54 uint64_t *p1, *p2, *p3;
55 p1 = p3 = list1;
56 p2 = list2;
57
58 while ( *p1 != -1 && *p2 != -1 ) {
59 if (compare_uint64(p1, p2) == 0) {
60 *p3++ = *p1++;
61 p2++;
62 }
63 else {
64 while (compare_uint64(p1, p2) < 0) ++p1;
65 while (compare_uint64(p1, p2) > 0) ++p2;
66 }
67 }
68 *p3 = -1;
69 return p3 - list1;
70 }
71
72
73 // Darkside attack (hf mf mifare)
74 static uint32_t nonce2key(uint32_t uid, uint32_t nt, uint32_t nr, uint64_t par_info, uint64_t ks_info, uint64_t **keys) {
75 struct Crypto1State *states;
76 uint32_t i, pos, rr; //nr_diff;
77 uint8_t bt, ks3x[8], par[8][8];
78 uint64_t key_recovered;
79 static uint64_t *keylist;
80 rr = 0;
81
82 // Reset the last three significant bits of the reader nonce
83 nr &= 0xffffff1f;
84
85 for (pos=0; pos<8; pos++) {
86 ks3x[7-pos] = (ks_info >> (pos*8)) & 0x0f;
87 bt = (par_info >> (pos*8)) & 0xff;
88 for (i=0; i<8; i++) {
89 par[7-pos][i] = (bt >> i) & 0x01;
90 }
91 }
92
93 states = lfsr_common_prefix(nr, rr, ks3x, par, (par_info == 0));
94
95 if (states == NULL) {
96 *keys = NULL;
97 return 0;
98 }
99
100 keylist = (uint64_t*)states;
101
102 for (i = 0; keylist[i]; i++) {
103 lfsr_rollback_word(states+i, uid^nt, 0);
104 crypto1_get_lfsr(states+i, &key_recovered);
105 keylist[i] = key_recovered;
106 }
107 keylist[i] = -1;
108
109 *keys = keylist;
110 return i;
111 }
112
113
114 int mfDarkside(uint64_t *key)
115 {
116 uint32_t uid = 0;
117 uint32_t nt = 0, nr = 0;
118 uint64_t par_list = 0, ks_list = 0;
119 uint64_t *keylist = NULL, *last_keylist = NULL;
120 uint32_t keycount = 0;
121 int16_t isOK = 0;
122
123 UsbCommand c = {CMD_READER_MIFARE, {true, 0, 0}};
124
125 // message
126 printf("-------------------------------------------------------------------------\n");
127 printf("Executing command. Expected execution time: 25sec on average\n");
128 printf("Press button on the proxmark3 device to abort both proxmark3 and client.\n");
129 printf("-------------------------------------------------------------------------\n");
130
131
132 while (true) {
133 clearCommandBuffer();
134 SendCommand(&c);
135
136 //flush queue
137 while (ukbhit()) {
138 int c = getchar(); (void) c;
139 }
140
141 // wait cycle
142 while (true) {
143 printf(".");
144 fflush(stdout);
145 if (ukbhit()) {
146 return -5;
147 break;
148 }
149
150 UsbCommand resp;
151 if (WaitForResponseTimeout(CMD_ACK, &resp, 1000)) {
152 isOK = resp.arg[0];
153 if (isOK < 0) {
154 return isOK;
155 }
156 uid = (uint32_t)bytes_to_num(resp.d.asBytes + 0, 4);
157 nt = (uint32_t)bytes_to_num(resp.d.asBytes + 4, 4);
158 par_list = bytes_to_num(resp.d.asBytes + 8, 8);
159 ks_list = bytes_to_num(resp.d.asBytes + 16, 8);
160 nr = bytes_to_num(resp.d.asBytes + 24, 4);
161 break;
162 }
163 }
164
165 if (par_list == 0 && c.arg[0] == true) {
166 PrintAndLog("Parity is all zero. Most likely this card sends NACK on every failed authentication.");
167 PrintAndLog("Attack will take a few seconds longer because we need two consecutive successful runs.");
168 }
169 c.arg[0] = false;
170
171 keycount = nonce2key(uid, nt, nr, par_list, ks_list, &keylist);
172
173 if (keycount == 0) {
174 PrintAndLog("Key not found (lfsr_common_prefix list is null). Nt=%08x", nt);
175 PrintAndLog("This is expected to happen in 25%% of all cases. Trying again with a different reader nonce...");
176 continue;
177 }
178
179 qsort(keylist, keycount, sizeof(*keylist), compare_uint64);
180 keycount = intersection(last_keylist, keylist);
181 if (keycount == 0) {
182 free(last_keylist);
183 last_keylist = keylist;
184 continue;
185 }
186
187 if (keycount > 1) {
188 PrintAndLog("Found %u possible keys. Trying to authenticate with each of them ...\n", keycount);
189 } else {
190 PrintAndLog("Found a possible key. Trying to authenticate...\n");
191 }
192
193 *key = -1;
194 uint8_t keyBlock[USB_CMD_DATA_SIZE];
195 int max_keys = USB_CMD_DATA_SIZE/6;
196 for (int i = 0; i < keycount; i += max_keys) {
197 int size = keycount - i > max_keys ? max_keys : keycount - i;
198 for (int j = 0; j < size; j++) {
199 if (last_keylist == NULL) {
200 num_to_bytes(keylist[i*max_keys + j], 6, keyBlock);
201 } else {
202 num_to_bytes(last_keylist[i*max_keys + j], 6, keyBlock);
203 }
204 }
205 if (!mfCheckKeys(0, 0, false, size, keyBlock, key)) {
206 break;
207 }
208 }
209
210 if (*key != -1) {
211 free(last_keylist);
212 free(keylist);
213 break;
214 } else {
215 PrintAndLog("Authentication failed. Trying again...");
216 free(last_keylist);
217 last_keylist = keylist;
218 }
219 }
220
221 return 0;
222 }
223
224
225 int mfCheckKeys (uint8_t blockNo, uint8_t keyType, bool clear_trace, uint8_t keycnt, uint8_t * keyBlock, uint64_t * key){
226
227 *key = 0;
228
229 UsbCommand c = {CMD_MIFARE_CHKKEYS, {((blockNo & 0xff) | ((keyType&0xff)<<8)), clear_trace, keycnt}};
230 memcpy(c.d.asBytes, keyBlock, 6 * keycnt);
231 SendCommand(&c);
232
233 UsbCommand resp;
234 if (!WaitForResponseTimeout(CMD_ACK,&resp,3000)) return 1;
235 if ((resp.arg[0] & 0xff) != 0x01) return 2;
236 *key = bytes_to_num(resp.d.asBytes, 6);
237 return 0;
238 }
239
240 // Compare 16 Bits out of cryptostate
241 int Compare16Bits(const void * a, const void * b) {
242 if ((*(uint64_t*)b & 0x00ff000000ff0000) == (*(uint64_t*)a & 0x00ff000000ff0000)) return 0;
243 else if ((*(uint64_t*)b & 0x00ff000000ff0000) > (*(uint64_t*)a & 0x00ff000000ff0000)) return 1;
244 else return -1;
245 }
246
247 typedef
248 struct {
249 union {
250 struct Crypto1State *slhead;
251 uint64_t *keyhead;
252 } head;
253 union {
254 struct Crypto1State *sltail;
255 uint64_t *keytail;
256 } tail;
257 uint32_t len;
258 uint32_t uid;
259 uint32_t blockNo;
260 uint32_t keyType;
261 uint32_t nt;
262 uint32_t ks1;
263 } StateList_t;
264
265
266 // wrapper function for multi-threaded lfsr_recovery32
267 void* nested_worker_thread(void *arg)
268 {
269 struct Crypto1State *p1;
270 StateList_t *statelist = arg;
271
272 statelist->head.slhead = lfsr_recovery32(statelist->ks1, statelist->nt ^ statelist->uid);
273 for (p1 = statelist->head.slhead; *(uint64_t *)p1 != 0; p1++);
274 statelist->len = p1 - statelist->head.slhead;
275 statelist->tail.sltail = --p1;
276 qsort(statelist->head.slhead, statelist->len, sizeof(uint64_t), Compare16Bits);
277
278 return statelist->head.slhead;
279 }
280
281 int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t *resultKey, bool calibrate)
282 {
283 uint16_t i;
284 uint32_t uid;
285 UsbCommand resp;
286
287 StateList_t statelists[2];
288 struct Crypto1State *p1, *p2, *p3, *p4;
289
290 // flush queue
291 WaitForResponseTimeout(CMD_ACK, NULL, 100);
292
293 UsbCommand c = {CMD_MIFARE_NESTED, {blockNo + keyType * 0x100, trgBlockNo + trgKeyType * 0x100, calibrate}};
294 memcpy(c.d.asBytes, key, 6);
295 SendCommand(&c);
296
297 if (!WaitForResponseTimeout(CMD_ACK, &resp, 1500)) {
298 return -1;
299 }
300
301 if (resp.arg[0]) {
302 return resp.arg[0]; // error during nested
303 }
304
305 memcpy(&uid, resp.d.asBytes, 4);
306 PrintAndLog("uid:%08x trgbl=%d trgkey=%x", uid, (uint16_t)resp.arg[2] & 0xff, (uint16_t)resp.arg[2] >> 8);
307
308 for (i = 0; i < 2; i++) {
309 statelists[i].blockNo = resp.arg[2] & 0xff;
310 statelists[i].keyType = (resp.arg[2] >> 8) & 0xff;
311 statelists[i].uid = uid;
312 memcpy(&statelists[i].nt, (void *)(resp.d.asBytes + 4 + i * 8 + 0), 4);
313 memcpy(&statelists[i].ks1, (void *)(resp.d.asBytes + 4 + i * 8 + 4), 4);
314 }
315
316 // calc keys
317
318 pthread_t thread_id[2];
319
320 // create and run worker threads
321 for (i = 0; i < 2; i++) {
322 pthread_create(thread_id + i, NULL, nested_worker_thread, &statelists[i]);
323 }
324
325 // wait for threads to terminate:
326 for (i = 0; i < 2; i++) {
327 pthread_join(thread_id[i], (void*)&statelists[i].head.slhead);
328 }
329
330
331 // the first 16 Bits of the cryptostate already contain part of our key.
332 // Create the intersection of the two lists based on these 16 Bits and
333 // roll back the cryptostate
334 p1 = p3 = statelists[0].head.slhead;
335 p2 = p4 = statelists[1].head.slhead;
336 while (p1 <= statelists[0].tail.sltail && p2 <= statelists[1].tail.sltail) {
337 if (Compare16Bits(p1, p2) == 0) {
338 struct Crypto1State savestate, *savep = &savestate;
339 savestate = *p1;
340 while(Compare16Bits(p1, savep) == 0 && p1 <= statelists[0].tail.sltail) {
341 *p3 = *p1;
342 lfsr_rollback_word(p3, statelists[0].nt ^ statelists[0].uid, 0);
343 p3++;
344 p1++;
345 }
346 savestate = *p2;
347 while(Compare16Bits(p2, savep) == 0 && p2 <= statelists[1].tail.sltail) {
348 *p4 = *p2;
349 lfsr_rollback_word(p4, statelists[1].nt ^ statelists[1].uid, 0);
350 p4++;
351 p2++;
352 }
353 }
354 else {
355 while (Compare16Bits(p1, p2) == -1) p1++;
356 while (Compare16Bits(p1, p2) == 1) p2++;
357 }
358 }
359 *(uint64_t*)p3 = -1;
360 *(uint64_t*)p4 = -1;
361 statelists[0].len = p3 - statelists[0].head.slhead;
362 statelists[1].len = p4 - statelists[1].head.slhead;
363 statelists[0].tail.sltail=--p3;
364 statelists[1].tail.sltail=--p4;
365
366 // the statelists now contain possible keys. The key we are searching for must be in the
367 // intersection of both lists. Create the intersection:
368 qsort(statelists[0].head.keyhead, statelists[0].len, sizeof(uint64_t), compare_uint64);
369 qsort(statelists[1].head.keyhead, statelists[1].len, sizeof(uint64_t), compare_uint64);
370 statelists[0].len = intersection(statelists[0].head.keyhead, statelists[1].head.keyhead);
371
372 memset(resultKey, 0, 6);
373 // The list may still contain several key candidates. Test each of them with mfCheckKeys
374 for (i = 0; i < statelists[0].len; i++) {
375 uint8_t keyBlock[6];
376 uint64_t key64;
377 crypto1_get_lfsr(statelists[0].head.slhead + i, &key64);
378 num_to_bytes(key64, 6, keyBlock);
379 key64 = 0;
380 if (!mfCheckKeys(statelists[0].blockNo, statelists[0].keyType, false, 1, keyBlock, &key64)) {
381 num_to_bytes(key64, 6, resultKey);
382 break;
383 }
384 }
385
386 free(statelists[0].head.slhead);
387 free(statelists[1].head.slhead);
388
389 return 0;
390 }
391
392 // EMULATOR
393
394 int mfEmlGetMem(uint8_t *data, int blockNum, int blocksCount) {
395 UsbCommand c = {CMD_MIFARE_EML_MEMGET, {blockNum, blocksCount, 0}};
396 SendCommand(&c);
397
398 UsbCommand resp;
399 if (!WaitForResponseTimeout(CMD_ACK,&resp,1500)) return 1;
400 memcpy(data, resp.d.asBytes, blocksCount * 16);
401 return 0;
402 }
403
404 int mfEmlSetMem(uint8_t *data, int blockNum, int blocksCount) {
405 UsbCommand c = {CMD_MIFARE_EML_MEMSET, {blockNum, blocksCount, 0}};
406 memcpy(c.d.asBytes, data, blocksCount * 16);
407 SendCommand(&c);
408 return 0;
409 }
410
411 // "MAGIC" CARD
412
413 int mfCGetBlock(uint8_t blockNo, uint8_t *data, uint8_t params) {
414 uint8_t isOK = 0;
415
416 UsbCommand c = {CMD_MIFARE_CGETBLOCK, {params, 0, blockNo}};
417 SendCommand(&c);
418
419 UsbCommand resp;
420 if (WaitForResponseTimeout(CMD_ACK,&resp,1500)) {
421 isOK = resp.arg[0] & 0xff;
422 memcpy(data, resp.d.asBytes, 16);
423 if (!isOK) return 2;
424 } else {
425 PrintAndLog("Command execute timeout");
426 return 1;
427 }
428 return 0;
429 }
430
431 int mfCSetBlock(uint8_t blockNo, uint8_t *data, uint8_t *uid, bool wantWipe, uint8_t params) {
432
433 uint8_t isOK = 0;
434 UsbCommand c = {CMD_MIFARE_CSETBLOCK, {wantWipe, params & (0xFE | (uid == NULL ? 0:1)), blockNo}};
435 memcpy(c.d.asBytes, data, 16);
436 SendCommand(&c);
437
438 UsbCommand resp;
439 if (WaitForResponseTimeout(CMD_ACK,&resp,1500)) {
440 isOK = resp.arg[0] & 0xff;
441 if (uid != NULL)
442 memcpy(uid, resp.d.asBytes, 4);
443 if (!isOK)
444 return 2;
445 } else {
446 PrintAndLog("Command execute timeout");
447 return 1;
448 }
449 return 0;
450 }
451
452 int mfCSetUID(uint8_t *uid, uint8_t *atqa, uint8_t *sak, uint8_t *oldUID, bool wantWipe) {
453 uint8_t oldblock0[16] = {0x00};
454 uint8_t block0[16] = {0x00};
455
456 int old = mfCGetBlock(0, oldblock0, CSETBLOCK_SINGLE_OPER);
457 if (old == 0) {
458 memcpy(block0, oldblock0, 16);
459 PrintAndLog("old block 0: %s", sprint_hex(block0,16));
460 } else {
461 PrintAndLog("Couldn't get old data. Will write over the last bytes of Block 0.");
462 }
463
464 // fill in the new values
465 // UID
466 memcpy(block0, uid, 4);
467 // Mifare UID BCC
468 block0[4] = block0[0]^block0[1]^block0[2]^block0[3];
469 // mifare classic SAK(byte 5) and ATQA(byte 6 and 7, reversed)
470 if (sak!=NULL)
471 block0[5]=sak[0];
472 if (atqa!=NULL) {
473 block0[6]=atqa[1];
474 block0[7]=atqa[0];
475 }
476 PrintAndLog("new block 0: %s", sprint_hex(block0,16));
477 return mfCSetBlock(0, block0, oldUID, wantWipe, CSETBLOCK_SINGLE_OPER);
478 }
479
480 // SNIFFER
481
482 // constants
483 static uint8_t trailerAccessBytes[4] = {0x08, 0x77, 0x8F, 0x00};
484
485 // variables
486 char logHexFileName[FILE_PATH_SIZE] = {0x00};
487 static uint8_t traceCard[4096] = {0x00};
488 static char traceFileName[FILE_PATH_SIZE] = {0x00};
489 static int traceState = TRACE_IDLE;
490 static uint8_t traceCurBlock = 0;
491 static uint8_t traceCurKey = 0;
492
493 struct Crypto1State *traceCrypto1 = NULL;
494
495 struct Crypto1State *revstate;
496 uint64_t lfsr;
497 uint32_t ks2;
498 uint32_t ks3;
499
500 uint32_t uid; // serial number
501 uint32_t nt; // tag challenge
502 uint32_t nr_enc; // encrypted reader challenge
503 uint32_t ar_enc; // encrypted reader response
504 uint32_t at_enc; // encrypted tag response
505
506 int isTraceCardEmpty(void) {
507 return ((traceCard[0] == 0) && (traceCard[1] == 0) && (traceCard[2] == 0) && (traceCard[3] == 0));
508 }
509
510 int isBlockEmpty(int blockN) {
511 for (int i = 0; i < 16; i++)
512 if (traceCard[blockN * 16 + i] != 0) return 0;
513
514 return 1;
515 }
516
517 int isBlockTrailer(int blockN) {
518 return ((blockN & 0x03) == 0x03);
519 }
520
521 int saveTraceCard(void) {
522 FILE * f;
523
524 if ((!strlen(traceFileName)) || (isTraceCardEmpty())) return 0;
525
526 f = fopen(traceFileName, "w+");
527 if ( !f ) return 1;
528
529 for (int i = 0; i < 64; i++) { // blocks
530 for (int j = 0; j < 16; j++) // bytes
531 fprintf(f, "%02x", *(traceCard + i * 16 + j));
532 fprintf(f,"\n");
533 }
534 fclose(f);
535 return 0;
536 }
537
538 int loadTraceCard(uint8_t *tuid) {
539 FILE * f;
540 char buf[64] = {0x00};
541 uint8_t buf8[64] = {0x00};
542 int i, blockNum;
543
544 if (!isTraceCardEmpty())
545 saveTraceCard();
546
547 memset(traceCard, 0x00, 4096);
548 memcpy(traceCard, tuid + 3, 4);
549
550 FillFileNameByUID(traceFileName, tuid, ".eml", 7);
551
552 f = fopen(traceFileName, "r");
553 if (!f) return 1;
554
555 blockNum = 0;
556
557 while(!feof(f)){
558
559 memset(buf, 0, sizeof(buf));
560 if (fgets(buf, sizeof(buf), f) == NULL) {
561 PrintAndLog("File reading error.");
562 fclose(f);
563 return 2;
564 }
565
566 if (strlen(buf) < 32){
567 if (feof(f)) break;
568 PrintAndLog("File content error. Block data must include 32 HEX symbols");
569 fclose(f);
570 return 2;
571 }
572 for (i = 0; i < 32; i += 2)
573 sscanf(&buf[i], "%02x", (unsigned int *)&buf8[i / 2]);
574
575 memcpy(traceCard + blockNum * 16, buf8, 16);
576
577 blockNum++;
578 }
579 fclose(f);
580
581 return 0;
582 }
583
584 int mfTraceInit(uint8_t *tuid, uint8_t *atqa, uint8_t sak, bool wantSaveToEmlFile) {
585
586 if (traceCrypto1)
587 crypto1_destroy(traceCrypto1);
588
589 traceCrypto1 = NULL;
590
591 if (wantSaveToEmlFile)
592 loadTraceCard(tuid);
593
594 traceCard[4] = traceCard[0] ^ traceCard[1] ^ traceCard[2] ^ traceCard[3];
595 traceCard[5] = sak;
596 memcpy(&traceCard[6], atqa, 2);
597 traceCurBlock = 0;
598 uid = bytes_to_num(tuid + 3, 4);
599
600 traceState = TRACE_IDLE;
601
602 return 0;
603 }
604
605 void mf_crypto1_decrypt(struct Crypto1State *pcs, uint8_t *data, int len, bool isEncrypted){
606 uint8_t bt = 0;
607 int i;
608
609 if (len != 1) {
610 for (i = 0; i < len; i++)
611 data[i] = crypto1_byte(pcs, 0x00, isEncrypted) ^ data[i];
612 } else {
613 bt = 0;
614 for (i = 0; i < 4; i++)
615 bt |= (crypto1_bit(pcs, 0, isEncrypted) ^ BIT(data[0], i)) << i;
616
617 data[0] = bt;
618 }
619 return;
620 }
621
622
623 int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
624 uint8_t data[64];
625
626 if (traceState == TRACE_ERROR) return 1;
627 if (len > 64) {
628 traceState = TRACE_ERROR;
629 return 1;
630 }
631
632 memcpy(data, data_src, len);
633 if ((traceCrypto1) && ((traceState == TRACE_IDLE) || (traceState > TRACE_AUTH_OK))) {
634 mf_crypto1_decrypt(traceCrypto1, data, len, 0);
635 PrintAndLog("dec> %s", sprint_hex(data, len));
636 AddLogHex(logHexFileName, "dec> ", data, len);
637 }
638
639 switch (traceState) {
640 case TRACE_IDLE:
641 // check packet crc16!
642 if ((len >= 4) && (!CheckCrc14443(CRC_14443_A, data, len))) {
643 PrintAndLog("dec> CRC ERROR!!!");
644 AddLogLine(logHexFileName, "dec> ", "CRC ERROR!!!");
645 traceState = TRACE_ERROR; // do not decrypt the next commands
646 return 1;
647 }
648
649 // AUTHENTICATION
650 if ((len ==4) && ((data[0] == 0x60) || (data[0] == 0x61))) {
651 traceState = TRACE_AUTH1;
652 traceCurBlock = data[1];
653 traceCurKey = data[0] == 60 ? 1:0;
654 return 0;
655 }
656
657 // READ
658 if ((len ==4) && ((data[0] == 0x30))) {
659 traceState = TRACE_READ_DATA;
660 traceCurBlock = data[1];
661 return 0;
662 }
663
664 // WRITE
665 if ((len ==4) && ((data[0] == 0xA0))) {
666 traceState = TRACE_WRITE_OK;
667 traceCurBlock = data[1];
668 return 0;
669 }
670
671 // HALT
672 if ((len ==4) && ((data[0] == 0x50) && (data[1] == 0x00))) {
673 traceState = TRACE_ERROR; // do not decrypt the next commands
674 return 0;
675 }
676
677 return 0;
678 break;
679
680 case TRACE_READ_DATA:
681 if (len == 18) {
682 traceState = TRACE_IDLE;
683
684 if (isBlockTrailer(traceCurBlock)) {
685 memcpy(traceCard + traceCurBlock * 16 + 6, data + 6, 4);
686 } else {
687 memcpy(traceCard + traceCurBlock * 16, data, 16);
688 }
689 if (wantSaveToEmlFile) saveTraceCard();
690 return 0;
691 } else {
692 traceState = TRACE_ERROR;
693 return 1;
694 }
695 break;
696
697 case TRACE_WRITE_OK:
698 if ((len == 1) && (data[0] == 0x0a)) {
699 traceState = TRACE_WRITE_DATA;
700
701 return 0;
702 } else {
703 traceState = TRACE_ERROR;
704 return 1;
705 }
706 break;
707
708 case TRACE_WRITE_DATA:
709 if (len == 18) {
710 traceState = TRACE_IDLE;
711
712 memcpy(traceCard + traceCurBlock * 16, data, 16);
713 if (wantSaveToEmlFile) saveTraceCard();
714 return 0;
715 } else {
716 traceState = TRACE_ERROR;
717 return 1;
718 }
719 break;
720
721 case TRACE_AUTH1:
722 if (len == 4) {
723 traceState = TRACE_AUTH2;
724 nt = bytes_to_num(data, 4);
725 return 0;
726 } else {
727 traceState = TRACE_ERROR;
728 return 1;
729 }
730 break;
731
732 case TRACE_AUTH2:
733 if (len == 8) {
734 traceState = TRACE_AUTH_OK;
735
736 nr_enc = bytes_to_num(data, 4);
737 ar_enc = bytes_to_num(data + 4, 4);
738 return 0;
739 } else {
740 traceState = TRACE_ERROR;
741 return 1;
742 }
743 break;
744
745 case TRACE_AUTH_OK:
746 if (len ==4) {
747 traceState = TRACE_IDLE;
748
749 at_enc = bytes_to_num(data, 4);
750
751 // decode key here)
752 ks2 = ar_enc ^ prng_successor(nt, 64);
753 ks3 = at_enc ^ prng_successor(nt, 96);
754 revstate = lfsr_recovery64(ks2, ks3);
755 lfsr_rollback_word(revstate, 0, 0);
756 lfsr_rollback_word(revstate, 0, 0);
757 lfsr_rollback_word(revstate, nr_enc, 1);
758 lfsr_rollback_word(revstate, uid ^ nt, 0);
759
760 crypto1_get_lfsr(revstate, &lfsr);
761 printf("key> %x%x\n", (unsigned int)((lfsr & 0xFFFFFFFF00000000) >> 32), (unsigned int)(lfsr & 0xFFFFFFFF));
762 AddLogUint64(logHexFileName, "key> ", lfsr);
763
764 int blockShift = ((traceCurBlock & 0xFC) + 3) * 16;
765 if (isBlockEmpty((traceCurBlock & 0xFC) + 3)) memcpy(traceCard + blockShift + 6, trailerAccessBytes, 4);
766
767 if (traceCurKey) {
768 num_to_bytes(lfsr, 6, traceCard + blockShift + 10);
769 } else {
770 num_to_bytes(lfsr, 6, traceCard + blockShift);
771 }
772 if (wantSaveToEmlFile) saveTraceCard();
773
774 if (traceCrypto1) {
775 crypto1_destroy(traceCrypto1);
776 }
777
778 // set cryptosystem state
779 traceCrypto1 = lfsr_recovery64(ks2, ks3);
780
781 // nt = crypto1_word(traceCrypto1, nt ^ uid, 1) ^ nt;
782
783 /* traceCrypto1 = crypto1_create(lfsr); // key in lfsr
784 crypto1_word(traceCrypto1, nt ^ uid, 0);
785 crypto1_word(traceCrypto1, ar, 1);
786 crypto1_word(traceCrypto1, 0, 0);
787 crypto1_word(traceCrypto1, 0, 0);*/
788
789 return 0;
790 } else {
791 traceState = TRACE_ERROR;
792 return 1;
793 }
794 break;
795
796 default:
797 traceState = TRACE_ERROR;
798 return 1;
799 }
800
801 return 0;
802 }
803
804 int tryDecryptWord(uint32_t nt, uint32_t ar_enc, uint32_t at_enc, uint8_t *data, int len){
805 /*
806 uint32_t nt; // tag challenge
807 uint32_t ar_enc; // encrypted reader response
808 uint32_t at_enc; // encrypted tag response
809 */
810 if (traceCrypto1) {
811 crypto1_destroy(traceCrypto1);
812 }
813 ks2 = ar_enc ^ prng_successor(nt, 64);
814 ks3 = at_enc ^ prng_successor(nt, 96);
815 traceCrypto1 = lfsr_recovery64(ks2, ks3);
816
817 mf_crypto1_decrypt(traceCrypto1, data, len, 0);
818
819 PrintAndLog("Decrypted data: [%s]", sprint_hex(data,len) );
820 crypto1_destroy(traceCrypto1);
821 return 0;
822 }
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