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1 //-----------------------------------------------------------------------------
2 // Copyright (C) 2010 iZsh <izsh at fail0verflow.com>, Hagen Fritsch
3 // Copyright (C) 2011 Gerhard de Koning Gans
4 // Copyright (C) 2014 Midnitesnake & Andy Davies & Martin Holst Swende
5 //
6 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
7 // at your option, any later version. See the LICENSE.txt file for the text of
8 // the license.
9 //-----------------------------------------------------------------------------
10 // High frequency iClass commands
11 //-----------------------------------------------------------------------------
12
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 #include <sys/stat.h>
17 #include "iso14443crc.h" // Can also be used for iClass, using 0xE012 as CRC-type
18 #include "data.h"
19 #include "proxmark3.h"
20 #include "ui.h"
21 #include "cmdparser.h"
22 #include "cmdhficlass.h"
23 #include "../include/common.h"
24 #include "util.h"
25 #include "cmdmain.h"
26 #include "loclass/des.h"
27 #include "loclass/cipherutils.h"
28 #include "loclass/cipher.h"
29 #include "loclass/ikeys.h"
30 #include "loclass/elite_crack.h"
31 #include "loclass/fileutils.h"
32
33 static int CmdHelp(const char *Cmd);
34
35 int xorbits_8(uint8_t val)
36 {
37 uint8_t res = val ^ (val >> 1); //1st pass
38 res = res ^ (res >> 1); // 2nd pass
39 res = res ^ (res >> 2); // 3rd pass
40 res = res ^ (res >> 4); // 4th pass
41 return res & 1;
42 }
43
44 int CmdHFiClassList(const char *Cmd)
45 {
46
47 bool ShowWaitCycles = false;
48 char param = param_getchar(Cmd, 0);
49
50 if (param != 0) {
51 PrintAndLog("List data in trace buffer.");
52 PrintAndLog("Usage: hf iclass list");
53 PrintAndLog("h - help");
54 PrintAndLog("sample: hf iclass list");
55 return 0;
56 }
57
58 uint8_t got[TRACE_BUFFER_SIZE];
59 GetFromBigBuf(got,sizeof(got),0);
60 WaitForResponse(CMD_ACK,NULL);
61
62 PrintAndLog("Recorded Activity");
63 PrintAndLog("");
64 PrintAndLog("Start = Start of Start Bit, End = End of last modulation. Src = Source of Transfer");
65 PrintAndLog("All times are in carrier periods (1/13.56Mhz)");
66 PrintAndLog("");
67 PrintAndLog(" Start | End | Src | Data");
68 PrintAndLog("-----------|-----------|-----|--------");
69
70 int i;
71 uint32_t first_timestamp = 0;
72 uint32_t timestamp;
73 bool tagToReader;
74 uint32_t parityBits;
75 uint8_t len;
76 uint8_t *frame;
77 uint32_t EndOfTransmissionTimestamp = 0;
78
79
80 for( i=0; i < TRACE_BUFFER_SIZE;)
81 {
82 //First 32 bits contain
83 // isResponse (1 bit)
84 // timestamp (remaining)
85 //Then paritybits
86 //Then length
87 timestamp = *((uint32_t *)(got+i));
88 parityBits = *((uint32_t *)(got+i+4));
89 len = got[i+8];
90 frame = (got+i+9);
91 uint32_t next_timestamp = (*((uint32_t *)(got+i+9))) & 0x7fffffff;
92
93 tagToReader = timestamp & 0x80000000;
94 timestamp &= 0x7fffffff;
95
96 if(i==0) {
97 first_timestamp = timestamp;
98 }
99
100 // Break and stick with current result idf buffer was not completely full
101 if (frame[0] == 0x44 && frame[1] == 0x44 && frame[2] == 0x44 && frame[3] == 0x44) break;
102
103 char line[1000] = "";
104
105 if(len)//We have some data to display
106 {
107 int j,oddparity;
108
109 for(j = 0; j < len ; j++)
110 {
111 oddparity = 0x01 ^ xorbits_8(frame[j] & 0xFF);
112
113 if (tagToReader && (oddparity != ((parityBits >> (len - j - 1)) & 0x01))) {
114 sprintf(line+(j*4), "%02x! ", frame[j]);
115 } else {
116 sprintf(line+(j*4), "%02x ", frame[j]);
117 }
118 }
119 }else
120 {
121 if (ShowWaitCycles) {
122 sprintf(line, "fdt (Frame Delay Time): %d", (next_timestamp - timestamp));
123 }
124 }
125
126 char *crc = "";
127
128 if(len > 2)
129 {
130 uint8_t b1, b2;
131 if(!tagToReader && len == 4) {
132 // Rough guess that this is a command from the reader
133 // For iClass the command byte is not part of the CRC
134 ComputeCrc14443(CRC_ICLASS, &frame[1], len-3, &b1, &b2);
135 }
136 else {
137 // For other data.. CRC might not be applicable (UPDATE commands etc.)
138 ComputeCrc14443(CRC_ICLASS, frame, len-2, &b1, &b2);
139 }
140
141 if (b1 != frame[len-2] || b2 != frame[len-1]) {
142 crc = (tagToReader & (len < 8)) ? "" : " !crc";
143 }
144 }
145
146 i += (len + 9);
147 EndOfTransmissionTimestamp = (*((uint32_t *)(got+i))) & 0x7fffffff;
148
149 // Not implemented for iclass on the ARM-side
150 //if (!ShowWaitCycles) i += 9;
151
152 PrintAndLog(" %9d | %9d | %s | %s %s",
153 (timestamp - first_timestamp),
154 (EndOfTransmissionTimestamp - first_timestamp),
155 (len?(tagToReader ? "Tag" : "Rdr"):" "),
156 line, crc);
157 }
158 return 0;
159 }
160
161 int CmdHFiClassListOld(const char *Cmd)
162 {
163 uint8_t got[1920];
164 GetFromBigBuf(got,sizeof(got),0);
165
166 PrintAndLog("recorded activity:");
167 PrintAndLog(" ETU :rssi: who bytes");
168 PrintAndLog("---------+----+----+-----------");
169
170 int i = 0;
171 int prev = -1;
172
173 for (;;) {
174 if(i >= 1900) {
175 break;
176 }
177
178 bool isResponse;
179 int timestamp = *((uint32_t *)(got+i));
180 if (timestamp & 0x80000000) {
181 timestamp &= 0x7fffffff;
182 isResponse = 1;
183 } else {
184 isResponse = 0;
185 }
186
187
188 int metric = 0;
189
190 int parityBits = *((uint32_t *)(got+i+4));
191 // 4 bytes of additional information...
192 // maximum of 32 additional parity bit information
193 //
194 // TODO:
195 // at each quarter bit period we can send power level (16 levels)
196 // or each half bit period in 256 levels.
197
198
199 int len = got[i+8];
200
201 if (len > 100) {
202 break;
203 }
204 if (i + len >= 1900) {
205 break;
206 }
207
208 uint8_t *frame = (got+i+9);
209
210 // Break and stick with current result if buffer was not completely full
211 if (frame[0] == 0x44 && frame[1] == 0x44 && frame[3] == 0x44) { break; }
212
213 char line[1000] = "";
214 int j;
215 for (j = 0; j < len; j++) {
216 int oddparity = 0x01;
217 int k;
218
219 for (k=0;k<8;k++) {
220 oddparity ^= (((frame[j] & 0xFF) >> k) & 0x01);
221 }
222
223 //if((parityBits >> (len - j - 1)) & 0x01) {
224 if (isResponse && (oddparity != ((parityBits >> (len - j - 1)) & 0x01))) {
225 sprintf(line+(j*4), "%02x! ", frame[j]);
226 }
227 else {
228 sprintf(line+(j*4), "%02x ", frame[j]);
229 }
230 }
231
232 char *crc;
233 crc = "";
234 if (len > 2) {
235 uint8_t b1, b2;
236 for (j = 0; j < (len - 1); j++) {
237 // gives problems... search for the reason..
238 /*if(frame[j] == 0xAA) {
239 switch(frame[j+1]) {
240 case 0x01:
241 crc = "[1] Two drops close after each other";
242 break;
243 case 0x02:
244 crc = "[2] Potential SOC with a drop in second half of bitperiod";
245 break;
246 case 0x03:
247 crc = "[3] Segment Z after segment X is not possible";
248 break;
249 case 0x04:
250 crc = "[4] Parity bit of a fully received byte was wrong";
251 break;
252 default:
253 crc = "[?] Unknown error";
254 break;
255 }
256 break;
257 }*/
258 }
259
260 if (strlen(crc)==0) {
261 if(!isResponse && len == 4) {
262 // Rough guess that this is a command from the reader
263 // For iClass the command byte is not part of the CRC
264 ComputeCrc14443(CRC_ICLASS, &frame[1], len-3, &b1, &b2);
265 }
266 else {
267 // For other data.. CRC might not be applicable (UPDATE commands etc.)
268 ComputeCrc14443(CRC_ICLASS, frame, len-2, &b1, &b2);
269 }
270 //printf("%1x %1x",(unsigned)b1,(unsigned)b2);
271 if (b1 != frame[len-2] || b2 != frame[len-1]) {
272 crc = (isResponse & (len < 8)) ? "" : " !crc";
273 } else {
274 crc = "";
275 }
276 }
277 } else {
278 crc = ""; // SHORT
279 }
280
281 char metricString[100];
282 if (isResponse) {
283 sprintf(metricString, "%3d", metric);
284 } else {
285 strcpy(metricString, " ");
286 }
287
288 PrintAndLog(" +%7d: %s: %s %s %s",
289 (prev < 0 ? 0 : (timestamp - prev)),
290 metricString,
291 (isResponse ? "TAG" : " "), line, crc);
292
293 prev = timestamp;
294 i += (len + 9);
295 }
296 return 0;
297 }
298
299 int CmdHFiClassSnoop(const char *Cmd)
300 {
301 UsbCommand c = {CMD_SNOOP_ICLASS};
302 SendCommand(&c);
303 return 0;
304 }
305
306 int CmdHFiClassSim(const char *Cmd)
307 {
308 uint8_t simType = 0;
309 uint8_t CSN[8] = {0, 0, 0, 0, 0, 0, 0, 0};
310
311 if (strlen(Cmd)<1) {
312 PrintAndLog("Usage: hf iclass sim [0 <CSN>] | x");
313 PrintAndLog(" options");
314 PrintAndLog(" 0 <CSN> simulate the given CSN");
315 PrintAndLog(" 1 simulate default CSN");
316 PrintAndLog(" 2 iterate CSNs, gather MACs");
317 PrintAndLog(" sample: hf iclass sim 0 031FEC8AF7FF12E0");
318 PrintAndLog(" sample: hf iclass sim 2");
319 return 0;
320 }
321
322 simType = param_get8(Cmd, 0);
323
324 if(simType == 0)
325 {
326 if (param_gethex(Cmd, 1, CSN, 16)) {
327 PrintAndLog("A CSN should consist of 16 HEX symbols");
328 return 1;
329 }
330 PrintAndLog("--simtype:%02x csn:%s", simType, sprint_hex(CSN, 8));
331
332 }
333 if(simType > 2)
334 {
335 PrintAndLog("Undefined simptype %d", simType);
336 return 1;
337 }
338 uint8_t numberOfCSNs=0;
339
340 if(simType == 2)
341 {
342 UsbCommand c = {CMD_SIMULATE_TAG_ICLASS, {simType,63}};
343 UsbCommand resp = {0};
344
345 uint8_t csns[64] = {
346 0x00,0x0B,0x0F,0xFF,0xF7,0xFF,0x12,0xE0 ,
347 0x00,0x13,0x94,0x7e,0x76,0xff,0x12,0xe0 ,
348 0x2a,0x99,0xac,0x79,0xec,0xff,0x12,0xe0 ,
349 0x17,0x12,0x01,0xfd,0xf7,0xff,0x12,0xe0 ,
350 0xcd,0x56,0x01,0x7c,0x6f,0xff,0x12,0xe0 ,
351 0x4b,0x5e,0x0b,0x72,0xef,0xff,0x12,0xe0 ,
352 0x00,0x73,0xd8,0x75,0x58,0xff,0x12,0xe0 ,
353 0x0c,0x90,0x32,0xf3,0x5d,0xff,0x12,0xe0 };
354
355 memcpy(c.d.asBytes, csns, 64);
356
357 SendCommand(&c);
358 if (!WaitForResponseTimeout(CMD_ACK, &resp, -1)) {
359 PrintAndLog("Command timed out");
360 return 0;
361 }
362
363 uint8_t num_mac_responses = resp.arg[1];
364 PrintAndLog("Mac responses: %d MACs obtained (should be 8)", num_mac_responses);
365
366 size_t datalen = 8*24;
367 /*
368 * Now, time to dump to file. We'll use this format:
369 * <8-byte CSN><8-byte CC><4 byte NR><4 byte MAC>....
370 * So, it should wind up as
371 * 8 * 24 bytes.
372 *
373 * The returndata from the pm3 is on the following format
374 * <4 byte NR><4 byte MAC>
375 * CC are all zeroes, CSN is the same as was sent in
376 **/
377 void* dump = malloc(datalen);
378 memset(dump,0,datalen);//<-- Need zeroes for the CC-field
379 uint8_t i = 0;
380 for(i = 0 ; i < 8 ; i++)
381 {
382 memcpy(dump+i*24, csns+i*8,8); //CSN
383 //8 zero bytes here...
384 //Then comes NR_MAC (eight bytes from the response)
385 memcpy(dump+i*24+16,resp.d.asBytes+i*8,8);
386
387 }
388 /** Now, save to dumpfile **/
389 saveFile("iclass_mac_attack", "bin", dump,datalen);
390 free(dump);
391 }else
392 {
393 UsbCommand c = {CMD_SIMULATE_TAG_ICLASS, {simType,numberOfCSNs}};
394 memcpy(c.d.asBytes, CSN, 8);
395 SendCommand(&c);
396 }
397
398 return 0;
399 }
400
401 int CmdHFiClassReader(const char *Cmd)
402 {
403 UsbCommand c = {CMD_READER_ICLASS, {0}};
404 SendCommand(&c);
405 UsbCommand resp;
406 while(!ukbhit()){
407 if (WaitForResponseTimeout(CMD_ACK,&resp,4500)) {
408 uint8_t isOK = resp.arg[0] & 0xff;
409 uint8_t * data = resp.d.asBytes;
410
411 PrintAndLog("isOk:%02x", isOK);
412
413 if(isOK > 0)
414 {
415 PrintAndLog("CSN: %s",sprint_hex(data,8));
416 }
417 if(isOK >= 1)
418 {
419 PrintAndLog("CC: %s",sprint_hex(data+8,8));
420 }else{
421 PrintAndLog("No CC obtained");
422 }
423 } else {
424 PrintAndLog("Command execute timeout");
425 }
426 }
427
428 return 0;
429 }
430
431 int CmdHFiClassReader_Replay(const char *Cmd)
432 {
433 uint8_t readerType = 0;
434 uint8_t MAC[4]={0x00, 0x00, 0x00, 0x00};
435
436 if (strlen(Cmd)<1) {
437 PrintAndLog("Usage: hf iclass replay <MAC>");
438 PrintAndLog(" sample: hf iclass replay 00112233");
439 return 0;
440 }
441
442 if (param_gethex(Cmd, 0, MAC, 8)) {
443 PrintAndLog("MAC must include 8 HEX symbols");
444 return 1;
445 }
446
447 UsbCommand c = {CMD_READER_ICLASS_REPLAY, {readerType}};
448 memcpy(c.d.asBytes, MAC, 4);
449 SendCommand(&c);
450
451 return 0;
452 }
453
454 int CmdHFiClassReader_Dump(const char *Cmd)
455 {
456 uint8_t readerType = 0;
457 uint8_t MAC[4]={0x00,0x00,0x00,0x00};
458 uint8_t KEY[8]={0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
459 uint8_t CSN[8]={0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
460 uint8_t CCNR[12]={0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
461 //uint8_t CC_temp[8]={0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
462 uint8_t div_key[8]={0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
463 uint8_t keytable[128] = {0};
464 int elite = 0;
465 uint8_t *used_key;
466 int i;
467 if (strlen(Cmd)<1)
468 {
469 PrintAndLog("Usage: hf iclass dump <Key> [e]");
470 PrintAndLog(" Key - A 16 byte master key");
471 PrintAndLog(" e - If 'e' is specified, the key is interpreted as the 16 byte");
472 PrintAndLog(" Custom Key (KCus), which can be obtained via reader-attack");
473 PrintAndLog(" See 'hf iclass sim 2'. This key should be on iclass-format");
474 PrintAndLog(" sample: hf iclass dump 0011223344556677");
475
476
477 return 0;
478 }
479
480 if (param_gethex(Cmd, 0, KEY, 16))
481 {
482 PrintAndLog("KEY must include 16 HEX symbols");
483 return 1;
484 }
485
486 if (param_getchar(Cmd, 1) == 'e')
487 {
488 PrintAndLog("Elite switch on");
489 elite = 1;
490
491 //calc h2
492 hash2(KEY, keytable);
493 printarr_human_readable("keytable", keytable, 128);
494
495 }
496
497
498 UsbCommand c = {CMD_READER_ICLASS, {0}};
499 c.arg[0] = FLAG_ICLASS_READER_ONLY_ONCE;
500
501 SendCommand(&c);
502
503 UsbCommand resp;
504 uint8_t key_sel[8] = {0x00};
505 uint8_t key_sel_p[8] = {0x00};
506
507 if (WaitForResponseTimeout(CMD_ACK,&resp,4500)) {
508 uint8_t isOK = resp.arg[0] & 0xff;
509 uint8_t * data = resp.d.asBytes;
510
511 memcpy(CSN,data,8);
512 memcpy(CCNR,data+8,8);
513
514 PrintAndLog("isOk:%02x", isOK);
515
516 if(isOK > 0)
517 {
518 PrintAndLog("CSN: %s",sprint_hex(CSN,8));
519 }
520 if(isOK > 1)
521 {
522 if(elite)
523 {
524
525 //Get the key index (hash1)
526 uint8_t key_index[8] = {0};
527
528 hash1(CSN, key_index);
529 printvar("hash1", key_index,8);
530 for(i = 0; i < 8 ; i++)
531 key_sel[i] = keytable[key_index[i]] & 0xFF;
532 printvar("k_sel", key_sel,8);
533 //Permute from iclass format to standard format
534 permutekey_rev(key_sel,key_sel_p);
535 used_key = key_sel_p;
536 }else{
537 //Perhaps this should also be permuted to std format?
538 // Something like the code below? I have no std system
539 // to test this with /Martin
540
541 //uint8_t key_sel_p[8] = { 0 };
542 //permutekey_rev(KEY,key_sel_p);
543 //used_key = key_sel_p;
544
545 used_key = KEY;
546
547 }
548 printvar("Used key",used_key,8);
549 diversifyKey(CSN,used_key, div_key);
550 printvar("Div key", div_key, 8);
551 printvar("CC_NR:",CCNR,12);
552 doMAC(CCNR,12,div_key, MAC);
553 printvar("MAC", MAC, 4);
554
555 UsbCommand d = {CMD_READER_ICLASS_REPLAY, {readerType}};
556 memcpy(d.d.asBytes, MAC, 4);
557 SendCommand(&d);
558
559 }else{
560 PrintAndLog("Failed to obtain CC! Aborting");
561 }
562 } else {
563 PrintAndLog("Command execute timeout");
564 }
565
566 return 0;
567 }
568
569 int CmdHFiClass_iso14443A_write(const char *Cmd)
570 {
571 uint8_t readerType = 0;
572 uint8_t MAC[4]={0x00,0x00,0x00,0x00};
573 uint8_t KEY[8]={0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
574 uint8_t CSN[8]={0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
575 uint8_t CCNR[12]={0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
576 uint8_t div_key[8]={0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
577
578 uint8_t blockNo=0;
579 uint8_t bldata[8]={0};
580
581 if (strlen(Cmd)<3)
582 {
583 PrintAndLog("Usage: hf iclass write <Key> <Block> <Data>");
584 PrintAndLog(" sample: hf iclass write 0011223344556677 10 AAAAAAAAAAAAAAAA");
585 return 0;
586 }
587
588 if (param_gethex(Cmd, 0, KEY, 16))
589 {
590 PrintAndLog("KEY must include 16 HEX symbols");
591 return 1;
592 }
593
594 blockNo = param_get8(Cmd, 1);
595 if (blockNo>32)
596 {
597 PrintAndLog("Error: Maximum number of blocks is 32 for iClass 2K Cards!");
598 return 1;
599 }
600 if (param_gethex(Cmd, 2, bldata, 8))
601 {
602 PrintAndLog("Block data must include 8 HEX symbols");
603 return 1;
604 }
605
606 UsbCommand c = {CMD_ICLASS_ISO14443A_WRITE, {0}};
607 SendCommand(&c);
608 UsbCommand resp;
609
610 if (WaitForResponseTimeout(CMD_ACK,&resp,4500)) {
611 uint8_t isOK = resp.arg[0] & 0xff;
612 uint8_t * data = resp.d.asBytes;
613
614 memcpy(CSN,data,8);
615 memcpy(CCNR,data+8,8);
616 PrintAndLog("DEBUG: %s",sprint_hex(CSN,8));
617 PrintAndLog("DEBUG: %s",sprint_hex(CCNR,8));
618 PrintAndLog("isOk:%02x", isOK);
619 } else {
620 PrintAndLog("Command execute timeout");
621 }
622
623 diversifyKey(CSN,KEY, div_key);
624
625 PrintAndLog("Div Key: %s",sprint_hex(div_key,8));
626 doMAC(CCNR, 12,div_key, MAC);
627
628 UsbCommand c2 = {CMD_ICLASS_ISO14443A_WRITE, {readerType,blockNo}};
629 memcpy(c2.d.asBytes, bldata, 8);
630 memcpy(c2.d.asBytes+8, MAC, 4);
631 SendCommand(&c2);
632
633 if (WaitForResponseTimeout(CMD_ACK,&resp,1500)) {
634 uint8_t isOK = resp.arg[0] & 0xff;
635 uint8_t * data = resp.d.asBytes;
636
637 if (isOK)
638 PrintAndLog("isOk:%02x data:%s", isOK, sprint_hex(data, 4));
639 else
640 PrintAndLog("isOk:%02x", isOK);
641 } else {
642 PrintAndLog("Command execute timeout");
643 }
644 return 0;
645 }
646
647
648 static command_t CommandTable[] =
649 {
650 {"help", CmdHelp, 1, "This help"},
651 {"list", CmdHFiClassList, 0, "List iClass history"},
652 {"snoop", CmdHFiClassSnoop, 0, "Eavesdrop iClass communication"},
653 {"sim", CmdHFiClassSim, 0, "Simulate iClass tag"},
654 {"reader",CmdHFiClassReader, 0, "Read an iClass tag"},
655 {"replay",CmdHFiClassReader_Replay, 0, "Read an iClass tag via Reply Attack"},
656 {"dump", CmdHFiClassReader_Dump, 0, "Authenticate and Dump iClass tag"},
657 {"write", CmdHFiClass_iso14443A_write, 0, "Authenticate and Write iClass block"},
658 {"replay", CmdHFiClassReader_Replay, 0, "Read an iClass tag via Reply Attack"},
659 {"dump", CmdHFiClassReader_Dump, 0, "Authenticate and Dump iClass tag"},
660 {"write", CmdHFiClass_iso14443A_write, 0, "Authenticate and Write iClass block"},
661 {NULL, NULL, 0, NULL}
662 };
663
664 int CmdHFiClass(const char *Cmd)
665 {
666 CmdsParse(CommandTable, Cmd);
667 return 0;
668 }
669
670 int CmdHelp(const char *Cmd)
671 {
672 CmdsHelp(CommandTable);
673 return 0;
674 }
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