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1 //-----------------------------------------------------------------------------
2 // Merlok - June 2011, 2012
3 // Gerhard de Koning Gans - May 2008
4 // Hagen Fritsch - June 2010
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 // Routines to support ISO 14443 type A.
11 //-----------------------------------------------------------------------------
12
13 #include "proxmark3.h"
14 #include "apps.h"
15 #include "util.h"
16 #include "string.h"
17 #include "cmd.h"
18
19 #include "iso14443crc.h"
20 #include "iso14443a.h"
21 #include "crapto1.h"
22 #include "mifareutil.h"
23
24 static uint32_t iso14a_timeout;
25 uint8_t *trace = (uint8_t *) BigBuf+TRACE_OFFSET;
26 int traceLen = 0;
27 int rsamples = 0;
28 int tracing = TRUE;
29 uint8_t trigger = 0;
30 // the block number for the ISO14443-4 PCB
31 static uint8_t iso14_pcb_blocknum = 0;
32
33 // CARD TO READER - manchester
34 // Sequence D: 11110000 modulation with subcarrier during first half
35 // Sequence E: 00001111 modulation with subcarrier during second half
36 // Sequence F: 00000000 no modulation with subcarrier
37 // READER TO CARD - miller
38 // Sequence X: 00001100 drop after half a period
39 // Sequence Y: 00000000 no drop
40 // Sequence Z: 11000000 drop at start
41 #define SEC_D 0xf0
42 #define SEC_E 0x0f
43 #define SEC_F 0x00
44 #define SEC_X 0x0c
45 #define SEC_Y 0x00
46 #define SEC_Z 0xc0
47
48 const uint8_t OddByteParity[256] = {
49 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
50 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
51 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
52 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
53 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
54 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
55 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
56 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
57 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
58 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
59 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
60 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
61 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
62 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
63 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
64 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1
65 };
66
67
68 void iso14a_set_trigger(bool enable) {
69 trigger = enable;
70 }
71
72 void iso14a_clear_trace() {
73 memset(trace, 0x44, TRACE_SIZE);
74 traceLen = 0;
75 }
76
77 void iso14a_set_tracing(bool enable) {
78 tracing = enable;
79 }
80
81 void iso14a_set_timeout(uint32_t timeout) {
82 iso14a_timeout = timeout;
83 }
84
85 //-----------------------------------------------------------------------------
86 // Generate the parity value for a byte sequence
87 //
88 //-----------------------------------------------------------------------------
89 byte_t oddparity (const byte_t bt)
90 {
91 return OddByteParity[bt];
92 }
93
94 uint32_t GetParity(const uint8_t * pbtCmd, int iLen)
95 {
96 int i;
97 uint32_t dwPar = 0;
98
99 // Generate the encrypted data
100 for (i = 0; i < iLen; i++) {
101 // Save the encrypted parity bit
102 dwPar |= ((OddByteParity[pbtCmd[i]]) << i);
103 }
104 return dwPar;
105 }
106
107 void AppendCrc14443a(uint8_t* data, int len)
108 {
109 ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1);
110 }
111
112 // The function LogTrace() is also used by the iClass implementation in iClass.c
113 int RAMFUNC LogTrace(const uint8_t * btBytes, int iLen, int iSamples, uint32_t dwParity, int bReader)
114 {
115 // Return when trace is full
116 if (traceLen >= TRACE_SIZE) return FALSE;
117
118 // Trace the random, i'm curious
119 rsamples += iSamples;
120 trace[traceLen++] = ((rsamples >> 0) & 0xff);
121 trace[traceLen++] = ((rsamples >> 8) & 0xff);
122 trace[traceLen++] = ((rsamples >> 16) & 0xff);
123 trace[traceLen++] = ((rsamples >> 24) & 0xff);
124 if (!bReader) {
125 trace[traceLen - 1] |= 0x80;
126 }
127 trace[traceLen++] = ((dwParity >> 0) & 0xff);
128 trace[traceLen++] = ((dwParity >> 8) & 0xff);
129 trace[traceLen++] = ((dwParity >> 16) & 0xff);
130 trace[traceLen++] = ((dwParity >> 24) & 0xff);
131 trace[traceLen++] = iLen;
132 memcpy(trace + traceLen, btBytes, iLen);
133 traceLen += iLen;
134 return TRUE;
135 }
136
137 //-----------------------------------------------------------------------------
138 // The software UART that receives commands from the reader, and its state
139 // variables.
140 //-----------------------------------------------------------------------------
141 static tUart Uart;
142
143 static RAMFUNC int MillerDecoding(int bit)
144 {
145 //int error = 0;
146 int bitright;
147
148 if(!Uart.bitBuffer) {
149 Uart.bitBuffer = bit ^ 0xFF0;
150 return FALSE;
151 }
152 else {
153 Uart.bitBuffer <<= 4;
154 Uart.bitBuffer ^= bit;
155 }
156
157 int EOC = FALSE;
158
159 if(Uart.state != STATE_UNSYNCD) {
160 Uart.posCnt++;
161
162 if((Uart.bitBuffer & Uart.syncBit) ^ Uart.syncBit) {
163 bit = 0x00;
164 }
165 else {
166 bit = 0x01;
167 }
168 if(((Uart.bitBuffer << 1) & Uart.syncBit) ^ Uart.syncBit) {
169 bitright = 0x00;
170 }
171 else {
172 bitright = 0x01;
173 }
174 if(bit != bitright) { bit = bitright; }
175
176 if(Uart.posCnt == 1) {
177 // measurement first half bitperiod
178 if(!bit) {
179 Uart.drop = DROP_FIRST_HALF;
180 }
181 }
182 else {
183 // measurement second half bitperiod
184 if(!bit & (Uart.drop == DROP_NONE)) {
185 Uart.drop = DROP_SECOND_HALF;
186 }
187 else if(!bit) {
188 // measured a drop in first and second half
189 // which should not be possible
190 Uart.state = STATE_ERROR_WAIT;
191 //error = 0x01;
192 }
193
194 Uart.posCnt = 0;
195
196 switch(Uart.state) {
197 case STATE_START_OF_COMMUNICATION:
198 Uart.shiftReg = 0;
199 if(Uart.drop == DROP_SECOND_HALF) {
200 // error, should not happen in SOC
201 Uart.state = STATE_ERROR_WAIT;
202 //error = 0x02;
203 }
204 else {
205 // correct SOC
206 Uart.state = STATE_MILLER_Z;
207 }
208 break;
209
210 case STATE_MILLER_Z:
211 Uart.bitCnt++;
212 Uart.shiftReg >>= 1;
213 if(Uart.drop == DROP_NONE) {
214 // logic '0' followed by sequence Y
215 // end of communication
216 Uart.state = STATE_UNSYNCD;
217 EOC = TRUE;
218 }
219 // if(Uart.drop == DROP_FIRST_HALF) {
220 // Uart.state = STATE_MILLER_Z; stay the same
221 // we see a logic '0' }
222 if(Uart.drop == DROP_SECOND_HALF) {
223 // we see a logic '1'
224 Uart.shiftReg |= 0x100;
225 Uart.state = STATE_MILLER_X;
226 }
227 break;
228
229 case STATE_MILLER_X:
230 Uart.shiftReg >>= 1;
231 if(Uart.drop == DROP_NONE) {
232 // sequence Y, we see a '0'
233 Uart.state = STATE_MILLER_Y;
234 Uart.bitCnt++;
235 }
236 if(Uart.drop == DROP_FIRST_HALF) {
237 // Would be STATE_MILLER_Z
238 // but Z does not follow X, so error
239 Uart.state = STATE_ERROR_WAIT;
240 //error = 0x03;
241 }
242 if(Uart.drop == DROP_SECOND_HALF) {
243 // We see a '1' and stay in state X
244 Uart.shiftReg |= 0x100;
245 Uart.bitCnt++;
246 }
247 break;
248
249 case STATE_MILLER_Y:
250 Uart.bitCnt++;
251 Uart.shiftReg >>= 1;
252 if(Uart.drop == DROP_NONE) {
253 // logic '0' followed by sequence Y
254 // end of communication
255 Uart.state = STATE_UNSYNCD;
256 EOC = TRUE;
257 }
258 if(Uart.drop == DROP_FIRST_HALF) {
259 // we see a '0'
260 Uart.state = STATE_MILLER_Z;
261 }
262 if(Uart.drop == DROP_SECOND_HALF) {
263 // We see a '1' and go to state X
264 Uart.shiftReg |= 0x100;
265 Uart.state = STATE_MILLER_X;
266 }
267 break;
268
269 case STATE_ERROR_WAIT:
270 // That went wrong. Now wait for at least two bit periods
271 // and try to sync again
272 if(Uart.drop == DROP_NONE) {
273 Uart.highCnt = 6;
274 Uart.state = STATE_UNSYNCD;
275 }
276 break;
277
278 default:
279 Uart.state = STATE_UNSYNCD;
280 Uart.highCnt = 0;
281 break;
282 }
283
284 Uart.drop = DROP_NONE;
285
286 // should have received at least one whole byte...
287 if((Uart.bitCnt == 2) && EOC && (Uart.byteCnt > 0)) {
288 return TRUE;
289 }
290
291 if(Uart.bitCnt == 9) {
292 Uart.output[Uart.byteCnt] = (Uart.shiftReg & 0xff);
293 Uart.byteCnt++;
294
295 Uart.parityBits <<= 1;
296 Uart.parityBits ^= ((Uart.shiftReg >> 8) & 0x01);
297
298 if(EOC) {
299 // when End of Communication received and
300 // all data bits processed..
301 return TRUE;
302 }
303 Uart.bitCnt = 0;
304 }
305
306 /*if(error) {
307 Uart.output[Uart.byteCnt] = 0xAA;
308 Uart.byteCnt++;
309 Uart.output[Uart.byteCnt] = error & 0xFF;
310 Uart.byteCnt++;
311 Uart.output[Uart.byteCnt] = 0xAA;
312 Uart.byteCnt++;
313 Uart.output[Uart.byteCnt] = (Uart.bitBuffer >> 8) & 0xFF;
314 Uart.byteCnt++;
315 Uart.output[Uart.byteCnt] = Uart.bitBuffer & 0xFF;
316 Uart.byteCnt++;
317 Uart.output[Uart.byteCnt] = (Uart.syncBit >> 3) & 0xFF;
318 Uart.byteCnt++;
319 Uart.output[Uart.byteCnt] = 0xAA;
320 Uart.byteCnt++;
321 return TRUE;
322 }*/
323 }
324
325 }
326 else {
327 bit = Uart.bitBuffer & 0xf0;
328 bit >>= 4;
329 bit ^= 0x0F;
330 if(bit) {
331 // should have been high or at least (4 * 128) / fc
332 // according to ISO this should be at least (9 * 128 + 20) / fc
333 if(Uart.highCnt == 8) {
334 // we went low, so this could be start of communication
335 // it turns out to be safer to choose a less significant
336 // syncbit... so we check whether the neighbour also represents the drop
337 Uart.posCnt = 1; // apparently we are busy with our first half bit period
338 Uart.syncBit = bit & 8;
339 Uart.samples = 3;
340 if(!Uart.syncBit) { Uart.syncBit = bit & 4; Uart.samples = 2; }
341 else if(bit & 4) { Uart.syncBit = bit & 4; Uart.samples = 2; bit <<= 2; }
342 if(!Uart.syncBit) { Uart.syncBit = bit & 2; Uart.samples = 1; }
343 else if(bit & 2) { Uart.syncBit = bit & 2; Uart.samples = 1; bit <<= 1; }
344 if(!Uart.syncBit) { Uart.syncBit = bit & 1; Uart.samples = 0;
345 if(Uart.syncBit && (Uart.bitBuffer & 8)) {
346 Uart.syncBit = 8;
347
348 // the first half bit period is expected in next sample
349 Uart.posCnt = 0;
350 Uart.samples = 3;
351 }
352 }
353 else if(bit & 1) { Uart.syncBit = bit & 1; Uart.samples = 0; }
354
355 Uart.syncBit <<= 4;
356 Uart.state = STATE_START_OF_COMMUNICATION;
357 Uart.drop = DROP_FIRST_HALF;
358 Uart.bitCnt = 0;
359 Uart.byteCnt = 0;
360 Uart.parityBits = 0;
361 //error = 0;
362 }
363 else {
364 Uart.highCnt = 0;
365 }
366 }
367 else {
368 if(Uart.highCnt < 8) {
369 Uart.highCnt++;
370 }
371 }
372 }
373
374 return FALSE;
375 }
376
377 //=============================================================================
378 // ISO 14443 Type A - Manchester
379 //=============================================================================
380 static tDemod Demod;
381
382 static RAMFUNC int ManchesterDecoding(int v)
383 {
384 int bit;
385 int modulation;
386 //int error = 0;
387
388 if(!Demod.buff) {
389 Demod.buff = 1;
390 Demod.buffer = v;
391 return FALSE;
392 }
393 else {
394 bit = Demod.buffer;
395 Demod.buffer = v;
396 }
397
398 if(Demod.state==DEMOD_UNSYNCD) {
399 Demod.output[Demod.len] = 0xfa;
400 Demod.syncBit = 0;
401 //Demod.samples = 0;
402 Demod.posCount = 1; // This is the first half bit period, so after syncing handle the second part
403
404 if(bit & 0x08) {
405 Demod.syncBit = 0x08;
406 }
407
408 if(bit & 0x04) {
409 if(Demod.syncBit) {
410 bit <<= 4;
411 }
412 Demod.syncBit = 0x04;
413 }
414
415 if(bit & 0x02) {
416 if(Demod.syncBit) {
417 bit <<= 2;
418 }
419 Demod.syncBit = 0x02;
420 }
421
422 if(bit & 0x01 && Demod.syncBit) {
423 Demod.syncBit = 0x01;
424 }
425
426 if(Demod.syncBit) {
427 Demod.len = 0;
428 Demod.state = DEMOD_START_OF_COMMUNICATION;
429 Demod.sub = SUB_FIRST_HALF;
430 Demod.bitCount = 0;
431 Demod.shiftReg = 0;
432 Demod.parityBits = 0;
433 Demod.samples = 0;
434 if(Demod.posCount) {
435 if(trigger) LED_A_OFF();
436 switch(Demod.syncBit) {
437 case 0x08: Demod.samples = 3; break;
438 case 0x04: Demod.samples = 2; break;
439 case 0x02: Demod.samples = 1; break;
440 case 0x01: Demod.samples = 0; break;
441 }
442 }
443 //error = 0;
444 }
445 }
446 else {
447 //modulation = bit & Demod.syncBit;
448 modulation = ((bit << 1) ^ ((Demod.buffer & 0x08) >> 3)) & Demod.syncBit;
449
450 Demod.samples += 4;
451
452 if(Demod.posCount==0) {
453 Demod.posCount = 1;
454 if(modulation) {
455 Demod.sub = SUB_FIRST_HALF;
456 }
457 else {
458 Demod.sub = SUB_NONE;
459 }
460 }
461 else {
462 Demod.posCount = 0;
463 if(modulation && (Demod.sub == SUB_FIRST_HALF)) {
464 if(Demod.state!=DEMOD_ERROR_WAIT) {
465 Demod.state = DEMOD_ERROR_WAIT;
466 Demod.output[Demod.len] = 0xaa;
467 //error = 0x01;
468 }
469 }
470 else if(modulation) {
471 Demod.sub = SUB_SECOND_HALF;
472 }
473
474 switch(Demod.state) {
475 case DEMOD_START_OF_COMMUNICATION:
476 if(Demod.sub == SUB_FIRST_HALF) {
477 Demod.state = DEMOD_MANCHESTER_D;
478 }
479 else {
480 Demod.output[Demod.len] = 0xab;
481 Demod.state = DEMOD_ERROR_WAIT;
482 //error = 0x02;
483 }
484 break;
485
486 case DEMOD_MANCHESTER_D:
487 case DEMOD_MANCHESTER_E:
488 if(Demod.sub == SUB_FIRST_HALF) {
489 Demod.bitCount++;
490 Demod.shiftReg = (Demod.shiftReg >> 1) ^ 0x100;
491 Demod.state = DEMOD_MANCHESTER_D;
492 }
493 else if(Demod.sub == SUB_SECOND_HALF) {
494 Demod.bitCount++;
495 Demod.shiftReg >>= 1;
496 Demod.state = DEMOD_MANCHESTER_E;
497 }
498 else {
499 Demod.state = DEMOD_MANCHESTER_F;
500 }
501 break;
502
503 case DEMOD_MANCHESTER_F:
504 // Tag response does not need to be a complete byte!
505 if(Demod.len > 0 || Demod.bitCount > 0) {
506 if(Demod.bitCount > 0) {
507 Demod.shiftReg >>= (9 - Demod.bitCount);
508 Demod.output[Demod.len] = Demod.shiftReg & 0xff;
509 Demod.len++;
510 // No parity bit, so just shift a 0
511 Demod.parityBits <<= 1;
512 }
513
514 Demod.state = DEMOD_UNSYNCD;
515 return TRUE;
516 }
517 else {
518 Demod.output[Demod.len] = 0xad;
519 Demod.state = DEMOD_ERROR_WAIT;
520 //error = 0x03;
521 }
522 break;
523
524 case DEMOD_ERROR_WAIT:
525 Demod.state = DEMOD_UNSYNCD;
526 break;
527
528 default:
529 Demod.output[Demod.len] = 0xdd;
530 Demod.state = DEMOD_UNSYNCD;
531 break;
532 }
533
534 if(Demod.bitCount>=9) {
535 Demod.output[Demod.len] = Demod.shiftReg & 0xff;
536 Demod.len++;
537
538 Demod.parityBits <<= 1;
539 Demod.parityBits ^= ((Demod.shiftReg >> 8) & 0x01);
540
541 Demod.bitCount = 0;
542 Demod.shiftReg = 0;
543 }
544
545 /*if(error) {
546 Demod.output[Demod.len] = 0xBB;
547 Demod.len++;
548 Demod.output[Demod.len] = error & 0xFF;
549 Demod.len++;
550 Demod.output[Demod.len] = 0xBB;
551 Demod.len++;
552 Demod.output[Demod.len] = bit & 0xFF;
553 Demod.len++;
554 Demod.output[Demod.len] = Demod.buffer & 0xFF;
555 Demod.len++;
556 Demod.output[Demod.len] = Demod.syncBit & 0xFF;
557 Demod.len++;
558 Demod.output[Demod.len] = 0xBB;
559 Demod.len++;
560 return TRUE;
561 }*/
562
563 }
564
565 } // end (state != UNSYNCED)
566
567 return FALSE;
568 }
569
570 //=============================================================================
571 // Finally, a `sniffer' for ISO 14443 Type A
572 // Both sides of communication!
573 //=============================================================================
574
575 //-----------------------------------------------------------------------------
576 // Record the sequence of commands sent by the reader to the tag, with
577 // triggering so that we start recording at the point that the tag is moved
578 // near the reader.
579 //-----------------------------------------------------------------------------
580 void RAMFUNC SnoopIso14443a(uint8_t param) {
581 // param:
582 // bit 0 - trigger from first card answer
583 // bit 1 - trigger from first reader 7-bit request
584
585 LEDsoff();
586 // init trace buffer
587 iso14a_clear_trace();
588
589 // We won't start recording the frames that we acquire until we trigger;
590 // a good trigger condition to get started is probably when we see a
591 // response from the tag.
592 // triggered == FALSE -- to wait first for card
593 int triggered = !(param & 0x03);
594
595 // The command (reader -> tag) that we're receiving.
596 // The length of a received command will in most cases be no more than 18 bytes.
597 // So 32 should be enough!
598 uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
599 // The response (tag -> reader) that we're receiving.
600 uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET);
601
602 // As we receive stuff, we copy it from receivedCmd or receivedResponse
603 // into trace, along with its length and other annotations.
604 //uint8_t *trace = (uint8_t *)BigBuf;
605
606 // The DMA buffer, used to stream samples from the FPGA
607 int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET;
608 int8_t *data = dmaBuf;
609 int maxDataLen = 0;
610 int dataLen = 0;
611
612 // Set up the demodulator for tag -> reader responses.
613 Demod.output = receivedResponse;
614 Demod.len = 0;
615 Demod.state = DEMOD_UNSYNCD;
616
617 // Set up the demodulator for the reader -> tag commands
618 memset(&Uart, 0, sizeof(Uart));
619 Uart.output = receivedCmd;
620 Uart.byteCntMax = 32; // was 100 (greg)//////////////////
621 Uart.state = STATE_UNSYNCD;
622
623 // Setup for the DMA.
624 FpgaSetupSsc();
625 FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
626
627 // And put the FPGA in the appropriate mode
628 // Signal field is off with the appropriate LED
629 LED_D_OFF();
630 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER);
631 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
632
633 // Count of samples received so far, so that we can include timing
634 // information in the trace buffer.
635 rsamples = 0;
636 // And now we loop, receiving samples.
637 while(true) {
638 if(BUTTON_PRESS()) {
639 DbpString("cancelled by button");
640 goto done;
641 }
642
643 LED_A_ON();
644 WDT_HIT();
645
646 int register readBufDataP = data - dmaBuf;
647 int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR;
648 if (readBufDataP <= dmaBufDataP){
649 dataLen = dmaBufDataP - readBufDataP;
650 } else {
651 dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP + 1;
652 }
653 // test for length of buffer
654 if(dataLen > maxDataLen) {
655 maxDataLen = dataLen;
656 if(dataLen > 400) {
657 Dbprintf("blew circular buffer! dataLen=0x%x", dataLen);
658 goto done;
659 }
660 }
661 if(dataLen < 1) continue;
662
663 // primary buffer was stopped( <-- we lost data!
664 if (!AT91C_BASE_PDC_SSC->PDC_RCR) {
665 AT91C_BASE_PDC_SSC->PDC_RPR = (uint32_t) dmaBuf;
666 AT91C_BASE_PDC_SSC->PDC_RCR = DMA_BUFFER_SIZE;
667 }
668 // secondary buffer sets as primary, secondary buffer was stopped
669 if (!AT91C_BASE_PDC_SSC->PDC_RNCR) {
670 AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf;
671 AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
672 }
673
674 LED_A_OFF();
675
676 rsamples += 4;
677 if(MillerDecoding((data[0] & 0xF0) >> 4)) {
678 LED_C_ON();
679
680 // check - if there is a short 7bit request from reader
681 if ((!triggered) && (param & 0x02) && (Uart.byteCnt == 1) && (Uart.bitCnt = 9)) triggered = TRUE;
682
683 if(triggered) {
684 if (!LogTrace(receivedCmd, Uart.byteCnt, 0 - Uart.samples, Uart.parityBits, TRUE)) break;
685 }
686 /* And ready to receive another command. */
687 Uart.state = STATE_UNSYNCD;
688 /* And also reset the demod code, which might have been */
689 /* false-triggered by the commands from the reader. */
690 Demod.state = DEMOD_UNSYNCD;
691 LED_B_OFF();
692 }
693
694 if(ManchesterDecoding(data[0] & 0x0F)) {
695 LED_B_ON();
696
697 if (!LogTrace(receivedResponse, Demod.len, 0 - Demod.samples, Demod.parityBits, FALSE)) break;
698
699 if ((!triggered) && (param & 0x01)) triggered = TRUE;
700
701 // And ready to receive another response.
702 memset(&Demod, 0, sizeof(Demod));
703 Demod.output = receivedResponse;
704 Demod.state = DEMOD_UNSYNCD;
705 LED_C_OFF();
706 }
707
708 data++;
709 if(data > dmaBuf + DMA_BUFFER_SIZE) {
710 data = dmaBuf;
711 }
712 } // main cycle
713
714 DbpString("COMMAND FINISHED");
715
716 done:
717 AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
718 Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.byteCnt=%x", maxDataLen, Uart.state, Uart.byteCnt);
719 Dbprintf("Uart.byteCntMax=%x, traceLen=%x, Uart.output[0]=%08x", Uart.byteCntMax, traceLen, (int)Uart.output[0]);
720 LEDsoff();
721 }
722
723 //-----------------------------------------------------------------------------
724 // Prepare tag messages
725 //-----------------------------------------------------------------------------
726 static void CodeIso14443aAsTagPar(const uint8_t *cmd, int len, uint32_t dwParity)
727 {
728 int i;
729
730 ToSendReset();
731
732 // Correction bit, might be removed when not needed
733 ToSendStuffBit(0);
734 ToSendStuffBit(0);
735 ToSendStuffBit(0);
736 ToSendStuffBit(0);
737 ToSendStuffBit(1); // 1
738 ToSendStuffBit(0);
739 ToSendStuffBit(0);
740 ToSendStuffBit(0);
741
742 // Send startbit
743 ToSend[++ToSendMax] = SEC_D;
744
745 for(i = 0; i < len; i++) {
746 int j;
747 uint8_t b = cmd[i];
748
749 // Data bits
750 for(j = 0; j < 8; j++) {
751 if(b & 1) {
752 ToSend[++ToSendMax] = SEC_D;
753 } else {
754 ToSend[++ToSendMax] = SEC_E;
755 }
756 b >>= 1;
757 }
758
759 // Get the parity bit
760 if ((dwParity >> i) & 0x01) {
761 ToSend[++ToSendMax] = SEC_D;
762 } else {
763 ToSend[++ToSendMax] = SEC_E;
764 }
765 }
766
767 // Send stopbit
768 ToSend[++ToSendMax] = SEC_F;
769
770 // Convert from last byte pos to length
771 ToSendMax++;
772 }
773
774 static void CodeIso14443aAsTag(const uint8_t *cmd, int len){
775 CodeIso14443aAsTagPar(cmd, len, GetParity(cmd, len));
776 }
777
778 //-----------------------------------------------------------------------------
779 // This is to send a NACK kind of answer, its only 3 bits, I know it should be 4
780 //-----------------------------------------------------------------------------
781 static void CodeStrangeAnswerAsTag()
782 {
783 int i;
784
785 ToSendReset();
786
787 // Correction bit, might be removed when not needed
788 ToSendStuffBit(0);
789 ToSendStuffBit(0);
790 ToSendStuffBit(0);
791 ToSendStuffBit(0);
792 ToSendStuffBit(1); // 1
793 ToSendStuffBit(0);
794 ToSendStuffBit(0);
795 ToSendStuffBit(0);
796
797 // Send startbit
798 ToSend[++ToSendMax] = SEC_D;
799
800 // 0
801 ToSend[++ToSendMax] = SEC_E;
802
803 // 0
804 ToSend[++ToSendMax] = SEC_E;
805
806 // 1
807 ToSend[++ToSendMax] = SEC_D;
808
809 // Send stopbit
810 ToSend[++ToSendMax] = SEC_F;
811
812 // Flush the buffer in FPGA!!
813 for(i = 0; i < 5; i++) {
814 ToSend[++ToSendMax] = SEC_F;
815 }
816
817 // Convert from last byte pos to length
818 ToSendMax++;
819 }
820
821 static void Code4bitAnswerAsTag(uint8_t cmd)
822 {
823 int i;
824
825 ToSendReset();
826
827 // Correction bit, might be removed when not needed
828 ToSendStuffBit(0);
829 ToSendStuffBit(0);
830 ToSendStuffBit(0);
831 ToSendStuffBit(0);
832 ToSendStuffBit(1); // 1
833 ToSendStuffBit(0);
834 ToSendStuffBit(0);
835 ToSendStuffBit(0);
836
837 // Send startbit
838 ToSend[++ToSendMax] = SEC_D;
839
840 uint8_t b = cmd;
841 for(i = 0; i < 4; i++) {
842 if(b & 1) {
843 ToSend[++ToSendMax] = SEC_D;
844 } else {
845 ToSend[++ToSendMax] = SEC_E;
846 }
847 b >>= 1;
848 }
849
850 // Send stopbit
851 ToSend[++ToSendMax] = SEC_F;
852
853 // Flush the buffer in FPGA!!
854 for(i = 0; i < 5; i++) {
855 ToSend[++ToSendMax] = SEC_F;
856 }
857
858 // Convert from last byte pos to length
859 ToSendMax++;
860 }
861
862 //-----------------------------------------------------------------------------
863 // Wait for commands from reader
864 // Stop when button is pressed
865 // Or return TRUE when command is captured
866 //-----------------------------------------------------------------------------
867 static int GetIso14443aCommandFromReader(uint8_t *received, int *len, int maxLen)
868 {
869 // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
870 // only, since we are receiving, not transmitting).
871 // Signal field is off with the appropriate LED
872 LED_D_OFF();
873 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
874
875 // Now run a `software UART' on the stream of incoming samples.
876 Uart.output = received;
877 Uart.byteCntMax = maxLen;
878 Uart.state = STATE_UNSYNCD;
879
880 for(;;) {
881 WDT_HIT();
882
883 if(BUTTON_PRESS()) return FALSE;
884
885 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
886 AT91C_BASE_SSC->SSC_THR = 0x00;
887 }
888 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
889 uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
890 if(MillerDecoding((b & 0xf0) >> 4)) {
891 *len = Uart.byteCnt;
892 return TRUE;
893 }
894 if(MillerDecoding(b & 0x0f)) {
895 *len = Uart.byteCnt;
896 return TRUE;
897 }
898 }
899 }
900 }
901
902 static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded);
903 int EmSend4bitEx(uint8_t resp, int correctionNeeded);
904 int EmSend4bit(uint8_t resp);
905 int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par);
906 int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par);
907 int EmSendCmdEx(uint8_t *resp, int respLen, int correctionNeeded);
908 int EmSendCmd(uint8_t *resp, int respLen);
909 int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par);
910
911 //-----------------------------------------------------------------------------
912 // Main loop of simulated tag: receive commands from reader, decide what
913 // response to send, and send it.
914 //-----------------------------------------------------------------------------
915 void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
916 {
917 // Enable and clear the trace
918 tracing = TRUE;
919 iso14a_clear_trace();
920
921 // This function contains the tag emulation
922 uint8_t sak;
923
924 // The first response contains the ATQA (note: bytes are transmitted in reverse order).
925 uint8_t response1[2];
926
927 switch (tagType) {
928 case 1: { // MIFARE Classic
929 // Says: I am Mifare 1k - original line
930 response1[0] = 0x04;
931 response1[1] = 0x00;
932 sak = 0x08;
933 } break;
934 case 2: { // MIFARE Ultralight
935 // Says: I am a stupid memory tag, no crypto
936 response1[0] = 0x04;
937 response1[1] = 0x00;
938 sak = 0x00;
939 } break;
940 case 3: { // MIFARE DESFire
941 // Says: I am a DESFire tag, ph33r me
942 response1[0] = 0x04;
943 response1[1] = 0x03;
944 sak = 0x20;
945 } break;
946 case 4: { // ISO/IEC 14443-4
947 // Says: I am a javacard (JCOP)
948 response1[0] = 0x04;
949 response1[1] = 0x00;
950 sak = 0x28;
951 } break;
952 default: {
953 Dbprintf("Error: unkown tagtype (%d)",tagType);
954 return;
955 } break;
956 }
957
958 // The second response contains the (mandatory) first 24 bits of the UID
959 uint8_t response2[5];
960
961 // Check if the uid uses the (optional) part
962 uint8_t response2a[5];
963 if (uid_2nd) {
964 response2[0] = 0x88;
965 num_to_bytes(uid_1st,3,response2+1);
966 num_to_bytes(uid_2nd,4,response2a);
967 response2a[4] = response2a[0] ^ response2a[1] ^ response2a[2] ^ response2a[3];
968
969 // Configure the ATQA and SAK accordingly
970 response1[0] |= 0x40;
971 sak |= 0x04;
972 } else {
973 num_to_bytes(uid_1st,4,response2);
974 // Configure the ATQA and SAK accordingly
975 response1[0] &= 0xBF;
976 sak &= 0xFB;
977 }
978
979 // Calculate the BitCountCheck (BCC) for the first 4 bytes of the UID.
980 response2[4] = response2[0] ^ response2[1] ^ response2[2] ^ response2[3];
981
982 // Prepare the mandatory SAK (for 4 and 7 byte UID)
983 uint8_t response3[3];
984 response3[0] = sak;
985 ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]);
986
987 // Prepare the optional second SAK (for 7 byte UID), drop the cascade bit
988 uint8_t response3a[3];
989 response3a[0] = sak & 0xFB;
990 ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);
991
992 uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce
993 uint8_t response6[] = { 0x03, 0x3B, 0x00, 0x00, 0x00 }; // dummy ATS (pseudo-ATR), answer to RATS
994 ComputeCrc14443(CRC_14443_A, response6, 3, &response6[3], &response6[4]);
995
996 uint8_t *resp = NULL;
997 int respLen;
998
999 // Longest possible response will be 16 bytes + 2 CRC = 18 bytes
1000 // This will need
1001 // 144 data bits (18 * 8)
1002 // 18 parity bits
1003 // 2 Start and stop
1004 // 1 Correction bit (Answer in 1172 or 1236 periods, see FPGA)
1005 // 1 just for the case
1006 // ----------- +
1007 // 166
1008 //
1009 // 166 bytes, since every bit that needs to be send costs us a byte
1010 //
1011
1012 // Respond with card type
1013 uint8_t *resp1 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);
1014 int resp1Len;
1015
1016 // Anticollision cascade1 - respond with uid
1017 uint8_t *resp2 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + 166);
1018 int resp2Len;
1019
1020 // Anticollision cascade2 - respond with 2nd half of uid if asked
1021 // we're only going to be asked if we set the 1st byte of the UID (during cascade1) to 0x88
1022 uint8_t *resp2a = (((uint8_t *)BigBuf) + 1140);
1023 int resp2aLen;
1024
1025 // Acknowledge select - cascade 1
1026 uint8_t *resp3 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*2));
1027 int resp3Len;
1028
1029 // Acknowledge select - cascade 2
1030 uint8_t *resp3a = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*3));
1031 int resp3aLen;
1032
1033 // Response to a read request - not implemented atm
1034 uint8_t *resp4 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*4));
1035 // int resp4Len;
1036
1037 // Authenticate response - nonce
1038 uint8_t *resp5 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*5));
1039 int resp5Len;
1040
1041 // Authenticate response - nonce
1042 uint8_t *resp6 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*6));
1043 int resp6Len;
1044
1045 uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
1046 int len;
1047
1048 // To control where we are in the protocol
1049 int order = 0;
1050 int lastorder;
1051
1052 // Just to allow some checks
1053 int happened = 0;
1054 int happened2 = 0;
1055
1056 int cmdsRecvd = 0;
1057 uint8_t* respdata = NULL;
1058 int respsize = 0;
1059 // uint8_t nack = 0x04;
1060
1061 memset(receivedCmd, 0x44, RECV_CMD_SIZE);
1062
1063 // Prepare the responses of the anticollision phase
1064 // there will be not enough time to do this at the moment the reader sends it REQA
1065
1066 // Answer to request
1067 CodeIso14443aAsTag(response1, sizeof(response1));
1068 memcpy(resp1, ToSend, ToSendMax); resp1Len = ToSendMax;
1069
1070 // Send our UID (cascade 1)
1071 CodeIso14443aAsTag(response2, sizeof(response2));
1072 memcpy(resp2, ToSend, ToSendMax); resp2Len = ToSendMax;
1073
1074 // Answer to select (cascade1)
1075 CodeIso14443aAsTag(response3, sizeof(response3));
1076 memcpy(resp3, ToSend, ToSendMax); resp3Len = ToSendMax;
1077
1078 // Send the cascade 2 2nd part of the uid
1079 CodeIso14443aAsTag(response2a, sizeof(response2a));
1080 memcpy(resp2a, ToSend, ToSendMax); resp2aLen = ToSendMax;
1081
1082 // Answer to select (cascade 2)
1083 CodeIso14443aAsTag(response3a, sizeof(response3a));
1084 memcpy(resp3a, ToSend, ToSendMax); resp3aLen = ToSendMax;
1085
1086 // Strange answer is an example of rare message size (3 bits)
1087 CodeStrangeAnswerAsTag();
1088 memcpy(resp4, ToSend, ToSendMax);// resp4Len = ToSendMax;
1089
1090 // Authentication answer (random nonce)
1091 CodeIso14443aAsTag(response5, sizeof(response5));
1092 memcpy(resp5, ToSend, ToSendMax); resp5Len = ToSendMax;
1093
1094 // dummy ATS (pseudo-ATR), answer to RATS
1095 CodeIso14443aAsTag(response6, sizeof(response6));
1096 memcpy(resp6, ToSend, ToSendMax); resp6Len = ToSendMax;
1097
1098 // We need to listen to the high-frequency, peak-detected path.
1099 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
1100 FpgaSetupSsc();
1101
1102 cmdsRecvd = 0;
1103
1104 LED_A_ON();
1105 for(;;) {
1106
1107 if(!GetIso14443aCommandFromReader(receivedCmd, &len, RECV_CMD_SIZE)) {
1108 DbpString("button press");
1109 break;
1110 }
1111
1112 if (tracing) {
1113 LogTrace(receivedCmd,len, 0, Uart.parityBits, TRUE);
1114 }
1115
1116 // doob - added loads of debug strings so we can see what the reader is saying to us during the sim as hi14alist is not populated
1117 // Okay, look at the command now.
1118 lastorder = order;
1119 if(receivedCmd[0] == 0x26) { // Received a REQUEST
1120 resp = resp1; respLen = resp1Len; order = 1;
1121 respdata = response1;
1122 respsize = sizeof(response1);
1123 } else if(receivedCmd[0] == 0x52) { // Received a WAKEUP
1124 resp = resp1; respLen = resp1Len; order = 6;
1125 respdata = response1;
1126 respsize = sizeof(response1);
1127 } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x93) { // Received request for UID (cascade 1)
1128 resp = resp2; respLen = resp2Len; order = 2;
1129 respdata = response2;
1130 respsize = sizeof(response2);
1131 } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x95) { // Received request for UID (cascade 2)
1132 resp = resp2a; respLen = resp2aLen; order = 20;
1133 respdata = response2a;
1134 respsize = sizeof(response2a);
1135 } else if(receivedCmd[1] == 0x70 && receivedCmd[0] == 0x93) { // Received a SELECT (cascade 1)
1136 resp = resp3; respLen = resp3Len; order = 3;
1137 respdata = response3;
1138 respsize = sizeof(response3);
1139 } else if(receivedCmd[1] == 0x70 && receivedCmd[0] == 0x95) { // Received a SELECT (cascade 2)
1140 resp = resp3a; respLen = resp3aLen; order = 30;
1141 respdata = response3a;
1142 respsize = sizeof(response3a);
1143 } else if(receivedCmd[0] == 0x30) { // Received a (plain) READ
1144 // resp = resp4; respLen = resp4Len; order = 4; // Do nothing
1145 // respdata = &nack;
1146 // respsize = sizeof(nack); // 4-bit answer
1147 EmSendCmdEx(data+(4*receivedCmd[0]),16,false);
1148 Dbprintf("Read request from reader: %x %x",receivedCmd[0],receivedCmd[1]);
1149 // We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
1150 respLen = 0;
1151 } else if(receivedCmd[0] == 0x50) { // Received a HALT
1152 // DbpString("Reader requested we HALT!:");
1153 // Do not respond
1154 resp = resp1; respLen = 0; order = 0;
1155 respdata = NULL;
1156 respsize = 0;
1157 } else if(receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61) { // Received an authentication request
1158 resp = resp5; respLen = resp5Len; order = 7;
1159 respdata = response5;
1160 respsize = sizeof(response5);
1161 } else if(receivedCmd[0] == 0xE0) { // Received a RATS request
1162 resp = resp6; respLen = resp6Len; order = 70;
1163 respdata = response6;
1164 respsize = sizeof(response6);
1165 } else {
1166 if (order == 7 && len ==8) {
1167 uint32_t nr = bytes_to_num(receivedCmd,4);
1168 uint32_t ar = bytes_to_num(receivedCmd+4,4);
1169 Dbprintf("Auth attempt {nr}{ar}: %08x %08x",nr,ar);
1170 } else {
1171 // Never seen this command before
1172 Dbprintf("Received unknown command (len=%d):",len);
1173 Dbhexdump(len,receivedCmd,false);
1174 }
1175 // Do not respond
1176 resp = resp1; respLen = 0; order = 0;
1177 respdata = NULL;
1178 respsize = 0;
1179 }
1180
1181 // Count number of wakeups received after a halt
1182 if(order == 6 && lastorder == 5) { happened++; }
1183
1184 // Count number of other messages after a halt
1185 if(order != 6 && lastorder == 5) { happened2++; }
1186
1187 // Look at last parity bit to determine timing of answer
1188 if((Uart.parityBits & 0x01) || receivedCmd[0] == 0x52) {
1189 // 1236, so correction bit needed
1190 //i = 0;
1191 }
1192
1193 if(cmdsRecvd > 999) {
1194 DbpString("1000 commands later...");
1195 break;
1196 } else {
1197 cmdsRecvd++;
1198 }
1199
1200 if(respLen > 0) {
1201 EmSendCmd14443aRaw(resp, respLen, receivedCmd[0] == 0x52);
1202 }
1203
1204 if (tracing) {
1205 if (respdata != NULL) {
1206 LogTrace(respdata,respsize, 0, SwapBits(GetParity(respdata,respsize),respsize), FALSE);
1207 }
1208 if(traceLen > TRACE_SIZE) {
1209 DbpString("Trace full");
1210 break;
1211 }
1212 }
1213
1214 memset(receivedCmd, 0x44, RECV_CMD_SIZE);
1215 }
1216
1217 Dbprintf("%x %x %x", happened, happened2, cmdsRecvd);
1218 LED_A_OFF();
1219 }
1220
1221 //-----------------------------------------------------------------------------
1222 // Transmit the command (to the tag) that was placed in ToSend[].
1223 //-----------------------------------------------------------------------------
1224 static void TransmitFor14443a(const uint8_t *cmd, int len, int *samples, int *wait)
1225 {
1226 int c;
1227
1228 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1229
1230 if (wait)
1231 if(*wait < 10)
1232 *wait = 10;
1233
1234 for(c = 0; c < *wait;) {
1235 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1236 AT91C_BASE_SSC->SSC_THR = 0x00; // For exact timing!
1237 c++;
1238 }
1239 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1240 volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
1241 (void)r;
1242 }
1243 WDT_HIT();
1244 }
1245
1246 c = 0;
1247 for(;;) {
1248 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1249 AT91C_BASE_SSC->SSC_THR = cmd[c];
1250 c++;
1251 if(c >= len) {
1252 break;
1253 }
1254 }
1255 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1256 volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
1257 (void)r;
1258 }
1259 WDT_HIT();
1260 }
1261 if (samples) *samples = (c + *wait) << 3;
1262 }
1263
1264 //-----------------------------------------------------------------------------
1265 // Prepare reader command (in bits, support short frames) to send to FPGA
1266 //-----------------------------------------------------------------------------
1267 void CodeIso14443aBitsAsReaderPar(const uint8_t * cmd, int bits, uint32_t dwParity)
1268 {
1269 int i, j;
1270 int last;
1271 uint8_t b;
1272
1273 ToSendReset();
1274
1275 // Start of Communication (Seq. Z)
1276 ToSend[++ToSendMax] = SEC_Z;
1277 last = 0;
1278
1279 size_t bytecount = nbytes(bits);
1280 // Generate send structure for the data bits
1281 for (i = 0; i < bytecount; i++) {
1282 // Get the current byte to send
1283 b = cmd[i];
1284 size_t bitsleft = MIN((bits-(i*8)),8);
1285
1286 for (j = 0; j < bitsleft; j++) {
1287 if (b & 1) {
1288 // Sequence X
1289 ToSend[++ToSendMax] = SEC_X;
1290 last = 1;
1291 } else {
1292 if (last == 0) {
1293 // Sequence Z
1294 ToSend[++ToSendMax] = SEC_Z;
1295 } else {
1296 // Sequence Y
1297 ToSend[++ToSendMax] = SEC_Y;
1298 last = 0;
1299 }
1300 }
1301 b >>= 1;
1302 }
1303
1304 // Only transmit (last) parity bit if we transmitted a complete byte
1305 if (j == 8) {
1306 // Get the parity bit
1307 if ((dwParity >> i) & 0x01) {
1308 // Sequence X
1309 ToSend[++ToSendMax] = SEC_X;
1310 last = 1;
1311 } else {
1312 if (last == 0) {
1313 // Sequence Z
1314 ToSend[++ToSendMax] = SEC_Z;
1315 } else {
1316 // Sequence Y
1317 ToSend[++ToSendMax] = SEC_Y;
1318 last = 0;
1319 }
1320 }
1321 }
1322 }
1323
1324 // End of Communication
1325 if (last == 0) {
1326 // Sequence Z
1327 ToSend[++ToSendMax] = SEC_Z;
1328 } else {
1329 // Sequence Y
1330 ToSend[++ToSendMax] = SEC_Y;
1331 last = 0;
1332 }
1333 // Sequence Y
1334 ToSend[++ToSendMax] = SEC_Y;
1335
1336 // Just to be sure!
1337 ToSend[++ToSendMax] = SEC_Y;
1338 ToSend[++ToSendMax] = SEC_Y;
1339 ToSend[++ToSendMax] = SEC_Y;
1340
1341 // Convert from last character reference to length
1342 ToSendMax++;
1343 }
1344
1345 //-----------------------------------------------------------------------------
1346 // Prepare reader command to send to FPGA
1347 //-----------------------------------------------------------------------------
1348 void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
1349 {
1350 CodeIso14443aBitsAsReaderPar(cmd,len*8,dwParity);
1351 }
1352
1353 //-----------------------------------------------------------------------------
1354 // Wait for commands from reader
1355 // Stop when button is pressed (return 1) or field was gone (return 2)
1356 // Or return 0 when command is captured
1357 //-----------------------------------------------------------------------------
1358 static int EmGetCmd(uint8_t *received, int *len, int maxLen)
1359 {
1360 *len = 0;
1361
1362 uint32_t timer = 0, vtime = 0;
1363 int analogCnt = 0;
1364 int analogAVG = 0;
1365
1366 // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
1367 // only, since we are receiving, not transmitting).
1368 // Signal field is off with the appropriate LED
1369 LED_D_OFF();
1370 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
1371
1372 // Set ADC to read field strength
1373 AT91C_BASE_ADC->ADC_CR = AT91C_ADC_SWRST;
1374 AT91C_BASE_ADC->ADC_MR =
1375 ADC_MODE_PRESCALE(32) |
1376 ADC_MODE_STARTUP_TIME(16) |
1377 ADC_MODE_SAMPLE_HOLD_TIME(8);
1378 AT91C_BASE_ADC->ADC_CHER = ADC_CHANNEL(ADC_CHAN_HF);
1379 // start ADC
1380 AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
1381
1382 // Now run a 'software UART' on the stream of incoming samples.
1383 Uart.output = received;
1384 Uart.byteCntMax = maxLen;
1385 Uart.state = STATE_UNSYNCD;
1386
1387 for(;;) {
1388 WDT_HIT();
1389
1390 if (BUTTON_PRESS()) return 1;
1391
1392 // test if the field exists
1393 if (AT91C_BASE_ADC->ADC_SR & ADC_END_OF_CONVERSION(ADC_CHAN_HF)) {
1394 analogCnt++;
1395 analogAVG += AT91C_BASE_ADC->ADC_CDR[ADC_CHAN_HF];
1396 AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
1397 if (analogCnt >= 32) {
1398 if ((33000 * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) {
1399 vtime = GetTickCount();
1400 if (!timer) timer = vtime;
1401 // 50ms no field --> card to idle state
1402 if (vtime - timer > 50) return 2;
1403 } else
1404 if (timer) timer = 0;
1405 analogCnt = 0;
1406 analogAVG = 0;
1407 }
1408 }
1409 // transmit none
1410 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1411 AT91C_BASE_SSC->SSC_THR = 0x00;
1412 }
1413 // receive and test the miller decoding
1414 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1415 volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1416 if(MillerDecoding((b & 0xf0) >> 4)) {
1417 *len = Uart.byteCnt;
1418 if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE);
1419 return 0;
1420 }
1421 if(MillerDecoding(b & 0x0f)) {
1422 *len = Uart.byteCnt;
1423 if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE);
1424 return 0;
1425 }
1426 }
1427 }
1428 }
1429
1430 static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded)
1431 {
1432 int i, u = 0;
1433 uint8_t b = 0;
1434
1435 // Modulate Manchester
1436 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD);
1437 AT91C_BASE_SSC->SSC_THR = 0x00;
1438 FpgaSetupSsc();
1439
1440 // include correction bit
1441 i = 1;
1442 if((Uart.parityBits & 0x01) || correctionNeeded) {
1443 // 1236, so correction bit needed
1444 i = 0;
1445 }
1446
1447 // send cycle
1448 for(;;) {
1449 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1450 volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1451 (void)b;
1452 }
1453 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1454 if(i > respLen) {
1455 b = 0xff; // was 0x00
1456 u++;
1457 } else {
1458 b = resp[i];
1459 i++;
1460 }
1461 AT91C_BASE_SSC->SSC_THR = b;
1462
1463 if(u > 4) break;
1464 }
1465 if(BUTTON_PRESS()) {
1466 break;
1467 }
1468 }
1469
1470 return 0;
1471 }
1472
1473 int EmSend4bitEx(uint8_t resp, int correctionNeeded){
1474 Code4bitAnswerAsTag(resp);
1475 int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded);
1476 if (tracing) LogTrace(&resp, 1, GetDeltaCountUS(), GetParity(&resp, 1), FALSE);
1477 return res;
1478 }
1479
1480 int EmSend4bit(uint8_t resp){
1481 return EmSend4bitEx(resp, 0);
1482 }
1483
1484 int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par){
1485 CodeIso14443aAsTagPar(resp, respLen, par);
1486 int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded);
1487 if (tracing) LogTrace(resp, respLen, GetDeltaCountUS(), par, FALSE);
1488 return res;
1489 }
1490
1491 int EmSendCmdEx(uint8_t *resp, int respLen, int correctionNeeded){
1492 return EmSendCmdExPar(resp, respLen, correctionNeeded, GetParity(resp, respLen));
1493 }
1494
1495 int EmSendCmd(uint8_t *resp, int respLen){
1496 return EmSendCmdExPar(resp, respLen, 0, GetParity(resp, respLen));
1497 }
1498
1499 int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par){
1500 return EmSendCmdExPar(resp, respLen, 0, par);
1501 }
1502
1503 //-----------------------------------------------------------------------------
1504 // Wait a certain time for tag response
1505 // If a response is captured return TRUE
1506 // If it takes to long return FALSE
1507 //-----------------------------------------------------------------------------
1508 static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer
1509 {
1510 // buffer needs to be 512 bytes
1511 int c;
1512
1513 // Set FPGA mode to "reader listen mode", no modulation (listen
1514 // only, since we are receiving, not transmitting).
1515 // Signal field is on with the appropriate LED
1516 LED_D_ON();
1517 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);
1518
1519 // Now get the answer from the card
1520 Demod.output = receivedResponse;
1521 Demod.len = 0;
1522 Demod.state = DEMOD_UNSYNCD;
1523
1524 uint8_t b;
1525 if (elapsed) *elapsed = 0;
1526
1527 c = 0;
1528 for(;;) {
1529 WDT_HIT();
1530
1531 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1532 AT91C_BASE_SSC->SSC_THR = 0x00; // To make use of exact timing of next command from reader!!
1533 if (elapsed) (*elapsed)++;
1534 }
1535 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1536 if(c < iso14a_timeout) { c++; } else { return FALSE; }
1537 b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1538 if(ManchesterDecoding((b>>4) & 0xf)) {
1539 *samples = ((c - 1) << 3) + 4;
1540 return TRUE;
1541 }
1542 if(ManchesterDecoding(b & 0x0f)) {
1543 *samples = c << 3;
1544 return TRUE;
1545 }
1546 }
1547 }
1548 }
1549
1550 void ReaderTransmitBitsPar(uint8_t* frame, int bits, uint32_t par)
1551 {
1552 int wait = 0;
1553 int samples = 0;
1554
1555 // This is tied to other size changes
1556 // uint8_t* frame_addr = ((uint8_t*)BigBuf) + 2024;
1557 CodeIso14443aBitsAsReaderPar(frame,bits,par);
1558
1559 // Select the card
1560 TransmitFor14443a(ToSend, ToSendMax, &samples, &wait);
1561 if(trigger)
1562 LED_A_ON();
1563
1564 // Store reader command in buffer
1565 if (tracing) LogTrace(frame,nbytes(bits),0,par,TRUE);
1566 }
1567
1568 void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par)
1569 {
1570 ReaderTransmitBitsPar(frame,len*8,par);
1571 }
1572
1573 void ReaderTransmit(uint8_t* frame, int len)
1574 {
1575 // Generate parity and redirect
1576 ReaderTransmitBitsPar(frame,len*8,GetParity(frame,len));
1577 }
1578
1579 int ReaderReceive(uint8_t* receivedAnswer)
1580 {
1581 int samples = 0;
1582 if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE;
1583 if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE);
1584 if(samples == 0) return FALSE;
1585 return Demod.len;
1586 }
1587
1588 int ReaderReceivePar(uint8_t* receivedAnswer, uint32_t * parptr)
1589 {
1590 int samples = 0;
1591 if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE;
1592 if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE);
1593 *parptr = Demod.parityBits;
1594 if(samples == 0) return FALSE;
1595 return Demod.len;
1596 }
1597
1598 /* performs iso14443a anticolision procedure
1599 * fills the uid pointer unless NULL
1600 * fills resp_data unless NULL */
1601 int iso14443a_select_card(byte_t* uid_ptr, iso14a_card_select_t* p_hi14a_card, uint32_t* cuid_ptr) {
1602 uint8_t wupa[] = { 0x52 }; // 0x26 - REQA 0x52 - WAKE-UP
1603 uint8_t sel_all[] = { 0x93,0x20 };
1604 uint8_t sel_uid[] = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
1605 uint8_t rats[] = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0
1606 uint8_t* resp = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); // was 3560 - tied to other size changes
1607 byte_t uid_resp[4];
1608 size_t uid_resp_len;
1609
1610 uint8_t sak = 0x04; // cascade uid
1611 int cascade_level = 0;
1612 int len;
1613
1614 // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
1615 ReaderTransmitBitsPar(wupa,7,0);
1616 // Receive the ATQA
1617 if(!ReaderReceive(resp)) return 0;
1618 // Dbprintf("atqa: %02x %02x",resp[0],resp[1]);
1619
1620 if(p_hi14a_card) {
1621 memcpy(p_hi14a_card->atqa, resp, 2);
1622 p_hi14a_card->uidlen = 0;
1623 memset(p_hi14a_card->uid,0,10);
1624 }
1625
1626 // clear uid
1627 if (uid_ptr) {
1628 memset(uid_ptr,0,8);
1629 }
1630
1631 // OK we will select at least at cascade 1, lets see if first byte of UID was 0x88 in
1632 // which case we need to make a cascade 2 request and select - this is a long UID
1633 // While the UID is not complete, the 3nd bit (from the right) is set in the SAK.
1634 for(; sak & 0x04; cascade_level++) {
1635 // SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97)
1636 sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2;
1637
1638 // SELECT_ALL
1639 ReaderTransmit(sel_all,sizeof(sel_all));
1640 if (!ReaderReceive(resp)) return 0;
1641
1642 // First backup the current uid
1643 memcpy(uid_resp,resp,4);
1644 uid_resp_len = 4;
1645 // Dbprintf("uid: %02x %02x %02x %02x",uid_resp[0],uid_resp[1],uid_resp[2],uid_resp[3]);
1646
1647 // calculate crypto UID
1648 if(cuid_ptr) {
1649 *cuid_ptr = bytes_to_num(uid_resp, 4);
1650 }
1651
1652 // Construct SELECT UID command
1653 memcpy(sel_uid+2,resp,5);
1654 AppendCrc14443a(sel_uid,7);
1655 ReaderTransmit(sel_uid,sizeof(sel_uid));
1656
1657 // Receive the SAK
1658 if (!ReaderReceive(resp)) return 0;
1659 sak = resp[0];
1660
1661 // Test if more parts of the uid are comming
1662 if ((sak & 0x04) && uid_resp[0] == 0x88) {
1663 // Remove first byte, 0x88 is not an UID byte, it CT, see page 3 of:
1664 // http://www.nxp.com/documents/application_note/AN10927.pdf
1665 memcpy(uid_resp, uid_resp + 1, 3);
1666 uid_resp_len = 3;
1667 }
1668
1669 if(uid_ptr) {
1670 memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
1671 }
1672
1673 if(p_hi14a_card) {
1674 memcpy(p_hi14a_card->uid + (cascade_level*3), uid_resp, uid_resp_len);
1675 p_hi14a_card->uidlen += uid_resp_len;
1676 }
1677 }
1678
1679 if(p_hi14a_card) {
1680 p_hi14a_card->sak = sak;
1681 p_hi14a_card->ats_len = 0;
1682 }
1683
1684 if( (sak & 0x20) == 0) {
1685 return 2; // non iso14443a compliant tag
1686 }
1687
1688 // Request for answer to select
1689 AppendCrc14443a(rats, 2);
1690 ReaderTransmit(rats, sizeof(rats));
1691
1692 if (!(len = ReaderReceive(resp))) return 0;
1693
1694 if(p_hi14a_card) {
1695 memcpy(p_hi14a_card->ats, resp, sizeof(p_hi14a_card->ats));
1696 p_hi14a_card->ats_len = len;
1697 }
1698
1699 // reset the PCB block number
1700 iso14_pcb_blocknum = 0;
1701 return 1;
1702 }
1703
1704 void iso14443a_setup() {
1705 // Set up the synchronous serial port
1706 FpgaSetupSsc();
1707 // Start from off (no field generated)
1708 // Signal field is off with the appropriate LED
1709 LED_D_OFF();
1710 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1711 SpinDelay(50);
1712
1713 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
1714
1715 // Now give it time to spin up.
1716 // Signal field is on with the appropriate LED
1717 LED_D_ON();
1718 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1719 SpinDelay(50);
1720
1721 iso14a_timeout = 2048; //default
1722 }
1723
1724 int iso14_apdu(uint8_t * cmd, size_t cmd_len, void * data) {
1725 uint8_t real_cmd[cmd_len+4];
1726 real_cmd[0] = 0x0a; //I-Block
1727 // put block number into the PCB
1728 real_cmd[0] |= iso14_pcb_blocknum;
1729 real_cmd[1] = 0x00; //CID: 0 //FIXME: allow multiple selected cards
1730 memcpy(real_cmd+2, cmd, cmd_len);
1731 AppendCrc14443a(real_cmd,cmd_len+2);
1732
1733 ReaderTransmit(real_cmd, cmd_len+4);
1734 size_t len = ReaderReceive(data);
1735 uint8_t * data_bytes = (uint8_t *) data;
1736 if (!len)
1737 return 0; //DATA LINK ERROR
1738 // if we received an I- or R(ACK)-Block with a block number equal to the
1739 // current block number, toggle the current block number
1740 else if (len >= 4 // PCB+CID+CRC = 4 bytes
1741 && ((data_bytes[0] & 0xC0) == 0 // I-Block
1742 || (data_bytes[0] & 0xD0) == 0x80) // R-Block with ACK bit set to 0
1743 && (data_bytes[0] & 0x01) == iso14_pcb_blocknum) // equal block numbers
1744 {
1745 iso14_pcb_blocknum ^= 1;
1746 }
1747
1748 return len;
1749 }
1750
1751 //-----------------------------------------------------------------------------
1752 // Read an ISO 14443a tag. Send out commands and store answers.
1753 //
1754 //-----------------------------------------------------------------------------
1755 void ReaderIso14443a(UsbCommand * c)
1756 {
1757 iso14a_command_t param = c->arg[0];
1758 uint8_t * cmd = c->d.asBytes;
1759 size_t len = c->arg[1];
1760 uint32_t arg0 = 0;
1761 byte_t buf[USB_CMD_DATA_SIZE];
1762
1763 iso14a_clear_trace();
1764 iso14a_set_tracing(true);
1765
1766 if(param & ISO14A_REQUEST_TRIGGER) {
1767 iso14a_set_trigger(1);
1768 }
1769
1770 if(param & ISO14A_CONNECT) {
1771 iso14443a_setup();
1772 arg0 = iso14443a_select_card(NULL,(iso14a_card_select_t*)buf,NULL);
1773 cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(iso14a_card_select_t));
1774 // UsbSendPacket((void *)ack, sizeof(UsbCommand));
1775 }
1776
1777 if(param & ISO14A_SET_TIMEOUT) {
1778 iso14a_timeout = c->arg[2];
1779 }
1780
1781 if(param & ISO14A_SET_TIMEOUT) {
1782 iso14a_timeout = c->arg[2];
1783 }
1784
1785 if(param & ISO14A_APDU) {
1786 arg0 = iso14_apdu(cmd, len, buf);
1787 cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
1788 // UsbSendPacket((void *)ack, sizeof(UsbCommand));
1789 }
1790
1791 if(param & ISO14A_RAW) {
1792 if(param & ISO14A_APPEND_CRC) {
1793 AppendCrc14443a(cmd,len);
1794 len += 2;
1795 }
1796 ReaderTransmit(cmd,len);
1797 arg0 = ReaderReceive(buf);
1798 // UsbSendPacket((void *)ack, sizeof(UsbCommand));
1799 cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
1800 }
1801
1802 if(param & ISO14A_REQUEST_TRIGGER) {
1803 iso14a_set_trigger(0);
1804 }
1805
1806 if(param & ISO14A_NO_DISCONNECT) {
1807 return;
1808 }
1809
1810 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1811 LEDsoff();
1812 }
1813
1814 #define TEST_LENGTH 100
1815 typedef struct mftest{
1816 uint8_t nt[8];
1817 uint8_t count;
1818 }mftest ;
1819
1820 /**
1821 *@brief Tunes the mifare attack settings. This method checks the nonce entropy when
1822 *using a specified timeout.
1823 *Different cards behave differently, some cards require up to a second to power down (and thus reset
1824 *token generator), other cards are fine with 50 ms.
1825 *
1826 * @param time
1827 * @return the entropy. A value of 100 (%) means that every nonce was unique, while a value close to
1828 *zero indicates a low entropy: the given timeout is sufficient to power down the card.
1829 */
1830 int TuneMifare(int time)
1831 {
1832 // Mifare AUTH
1833 uint8_t mf_auth[] = { 0x60,0x00,0xf5,0x7b };
1834 uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);
1835
1836 iso14443a_setup();
1837 int TIME1=time;
1838 int TIME2=2000;
1839 uint8_t uid[8];
1840 uint32_t cuid;
1841 byte_t nt[4];
1842 Dbprintf("Tuning... testing a delay of %d ms (press button to skip)",time);
1843
1844
1845 mftest nt_values[TEST_LENGTH];
1846 int nt_size = 0;
1847 int i = 0;
1848 for(i = 0 ; i< 100 ; i++)
1849 {
1850 LED_C_OFF();
1851 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1852 SpinDelay(TIME1);
1853 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1854 LED_C_ON();
1855 SpinDelayUs(TIME2);
1856 if(!iso14443a_select_card(uid, NULL, &cuid)) continue;
1857
1858 // Transmit MIFARE_CLASSIC_AUTH
1859 ReaderTransmit(mf_auth, sizeof(mf_auth));
1860
1861 // Receive the (16 bit) "random" nonce
1862 if (!ReaderReceive(receivedAnswer)) continue;
1863 memcpy(nt, receivedAnswer, 4);
1864
1865 //store it
1866 int already_stored = 0;
1867 for(int i = 0 ; i < nt_size && !already_stored; i++)
1868 {
1869 if( memcmp(nt, nt_values[i].nt, 4) == 0)
1870 {
1871 nt_values[i].count++;
1872 already_stored = 1;
1873 }
1874 }
1875 if(!already_stored)
1876 {
1877 mftest* ptr= &nt_values[nt_size++];
1878 //Clear it before use
1879 memset(ptr, 0, sizeof(mftest));
1880 memcpy(ptr->nt, nt, 4);
1881 ptr->count = 1;
1882 }
1883
1884 if(BUTTON_PRESS())
1885 {
1886 Dbprintf("Tuning aborted prematurely");
1887 break;
1888 }
1889 }
1890 /*
1891 for(int i = 0 ; i < nt_size;i++){
1892 mftest x = nt_values[i];
1893 Dbprintf("%d,%d,%d,%d : %d",x.nt[0],x.nt[1],x.nt[2],x.nt[3],x.count);
1894 }
1895 */
1896 int result = nt_size *100 / i;
1897 Dbprintf(" ... results for %d ms : %d %",time, result);
1898 return result;
1899 }
1900
1901 //-----------------------------------------------------------------------------
1902 // Read an ISO 14443a tag. Send out commands and store answers.
1903 //
1904 //-----------------------------------------------------------------------------
1905 #define STATE_SIZE 100
1906 typedef struct AttackState{
1907 byte_t nt[4];
1908 byte_t par_list[8];
1909 byte_t ks_list[8];
1910 byte_t par;
1911 byte_t par_low;
1912 byte_t nt_diff;
1913 uint8_t mf_nr_ar[8];
1914 } AttackState;
1915
1916
1917 int continueAttack(AttackState* pState,uint8_t* receivedAnswer)
1918 {
1919
1920 // Transmit reader nonce and reader answer
1921 ReaderTransmitPar(pState->mf_nr_ar, sizeof(pState->mf_nr_ar),pState->par);
1922
1923 // Receive 4 bit answer
1924 int len = ReaderReceive(receivedAnswer);
1925 if (!len)
1926 {
1927 if (pState->nt_diff == 0)
1928 {
1929 pState->par++;
1930 } else {
1931 pState->par = (((pState->par >> 3) + 1) << 3) | pState->par_low;
1932 }
1933 return 2;
1934 }
1935 if(pState->nt_diff == 0)
1936 {
1937 pState->par_low = pState->par & 0x07;
1938 }
1939 //Dbprintf("answer received, parameter (%d), (memcmp(nt, nt_no)=%d",parameter,memcmp(nt, nt_noattack, 4));
1940 //if ( (parameter != 0) && (memcmp(nt, nt_noattack, 4) == 0) ) continue;
1941 //isNULL = 0;//|| !(nt_attacked[0] == 0) && (nt_attacked[1] == 0) && (nt_attacked[2] == 0) && (nt_attacked[3] == 0);
1942 //
1943 // if ( /*(isNULL != 0 ) && */(memcmp(nt, nt_attacked, 4) != 0) ) continue;
1944
1945 //led_on = !led_on;
1946 //if(led_on) LED_B_ON(); else LED_B_OFF();
1947 pState->par_list[pState->nt_diff] = pState->par;
1948 pState->ks_list[pState->nt_diff] = receivedAnswer[0] ^ 0x05;
1949
1950 // Test if the information is complete
1951 if (pState->nt_diff == 0x07) {
1952 return 0;
1953 }
1954
1955 pState->nt_diff = (pState->nt_diff + 1) & 0x07;
1956 pState->mf_nr_ar[3] = pState->nt_diff << 5;
1957 pState->par = pState->par_low;
1958 return 1;
1959 }
1960
1961 void reportResults(uint8_t uid[8],AttackState *pState, int isOK)
1962 {
1963 LogTrace(pState->nt, 4, 0, GetParity(pState->nt, 4), TRUE);
1964 LogTrace(pState->par_list, 8, 0, GetParity(pState->par_list, 8), TRUE);
1965 LogTrace(pState->ks_list, 8, 0, GetParity(pState->ks_list, 8), TRUE);
1966
1967 byte_t buf[48];
1968 memcpy(buf + 0, uid, 4);
1969 if(pState != NULL)
1970 {
1971 memcpy(buf + 4, pState->nt, 4);
1972 memcpy(buf + 8, pState->par_list, 8);
1973 memcpy(buf + 16, pState->ks_list, 8);
1974 }
1975
1976 LED_B_ON();
1977 cmd_send(CMD_ACK,isOK,0,0,buf,48);
1978 LED_B_OFF();
1979
1980 // Thats it...
1981 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1982 LEDsoff();
1983 tracing = TRUE;
1984
1985 if (MF_DBGLEVEL >= 1) DbpString("COMMAND mifare FINISHED");
1986 }
1987
1988 void ReaderMifareBegin(uint32_t offset_time, uint32_t powerdown_time);
1989
1990 /**
1991 * @brief New implementation of ReaderMifare, the classic mifare attack.
1992 * This implementation is backwards-compatible, but has some added parameters.
1993 * @param c the usbcommand in complete
1994 * c->arg[0] - nt_noattack (deprecated)
1995 * c->arg[1] - offset_time us (0 => random)
1996 * c->arg[2] - powerdown_time ms (0=> tuning)
1997 *
1998 */
1999 void ReaderMifare(UsbCommand *c)
2000 {
2001 /*
2002 * The 'no-attack' is not used anymore, with the introduction of
2003 * state tables. Instead, we use an offset which is random. This means that we
2004 * should not get stuck on a 'bad' nonce, so no-attack is not needed.
2005 * Anyway, arg[0] is reserved for backwards compatibility
2006 uint32_t nt_noattack_uint = c->arg[0];
2007 byte_t nt_noattack[4];
2008 num_to_bytes(parameter, 4, nt_noattack_uint);
2009
2010 */
2011 /*
2012 *IF, for some reason, you want to attack a specific nonce or whatever,
2013 *you can specify the offset time yourself, in which case it won't be random.
2014 *
2015 * The offset time is microseconds, MICROSECONDS, not ms.
2016 */
2017 uint32_t offset_time = c->arg[1];
2018 if(offset_time == 0)
2019 {
2020 //[Martin:]I would like to have used rand(), but linking problems prevented it
2021 //offset_time = rand() % 4000;
2022 //So instead, I found this nifty thingy, which seems to fit the bill
2023 offset_time = GetTickCount() % 2000;
2024 }
2025 /*
2026 * There is an implementation of tuning. Tuning will try to determine
2027 * a good power-down time, which is different for different cards.
2028 * If a value is specified from the packet, we won't do any tuning.
2029 * A value of zero will initialize a tuning.
2030 * The power-down time is milliseconds, that MILLI-seconds .
2031 */
2032 uint32_t powerdown_time = c->arg[2];
2033 if(powerdown_time == 0)
2034 {
2035 //Tuning required
2036 int entropy = 100;
2037 int time = 25;
2038 entropy = TuneMifare(time);
2039
2040 while(entropy > 50 && time < 2000){
2041 //Increase timeout, but never more than 500ms at a time
2042 time = MIN(time*2, time+500);
2043 entropy = TuneMifare(time);
2044 }
2045 if(entropy > 50){
2046 Dbprintf("OBS! This card has high entropy (%d) and slow power-down. This may take a while", entropy);
2047 }
2048 powerdown_time = time;
2049 }
2050 //The actual attack
2051 ReaderMifareBegin(offset_time, powerdown_time);
2052 }
2053 void ReaderMifareBegin(uint32_t offset_time, uint32_t powerdown_time)
2054 {
2055 Dbprintf("Using power-down-time of %d ms, offset time %d us", powerdown_time, offset_time);
2056
2057 /**
2058 *Allocate our state-table and initialize with zeroes
2059 **/
2060
2061 AttackState states[STATE_SIZE] ;
2062 //Dbprintf("Memory allocated ok! (%d bytes)",STATE_SIZE*sizeof(AttackState) );
2063 memset(states, 0, STATE_SIZE*sizeof(AttackState));
2064
2065 // Mifare AUTH
2066 uint8_t mf_auth[] = { 0x60,0x00,0xf5,0x7b };
2067 uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); // was 3560 - tied to other size changes
2068
2069 traceLen = 0;
2070 tracing = false;
2071
2072 iso14443a_setup();
2073 LED_A_ON();
2074 LED_B_OFF();
2075 LED_C_OFF();
2076
2077 LED_A_OFF();
2078 uint8_t uid[8];
2079 uint32_t cuid;
2080
2081 byte_t nt[4];
2082 int nts_attacked= 0;
2083 //Keeps track of progress (max value of nt_diff for our states)
2084 int progress = 0;
2085 int high_entropy_warning_issued = 0;
2086 while(!BUTTON_PRESS())
2087 {
2088 LED_C_OFF();
2089 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
2090 SpinDelay(powerdown_time);
2091 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
2092 LED_C_ON();
2093 SpinDelayUs(offset_time);
2094
2095 if(!iso14443a_select_card(uid, NULL, &cuid)) continue;
2096
2097 // Transmit MIFARE_CLASSIC_AUTH
2098 ReaderTransmit(mf_auth, sizeof(mf_auth));
2099
2100 // Receive the (16 bit) "random" nonce
2101 if (!ReaderReceive(receivedAnswer)) continue;
2102 memcpy(nt, receivedAnswer, 4);
2103
2104 //Now we have the NT. Check if this NT is already under attack
2105 AttackState* pState = NULL;
2106 int i = 0;
2107 for(i = 0 ; i < nts_attacked && pState == NULL; i++)
2108 {
2109 if( memcmp(nt, states[i].nt, 4) == 0)
2110 {
2111 //we have it
2112 pState = &states[i];
2113 //Dbprintf("Existing state found (%d)", i);
2114 }
2115 }
2116
2117 if(pState == NULL){
2118 if(nts_attacked < STATE_SIZE )
2119 {
2120 //Initialize a new state
2121 pState = &states[nts_attacked++];
2122 //Clear it before use
2123 memset(pState, 0, sizeof(AttackState));
2124 memcpy(pState->nt, nt, 4);
2125 i = nts_attacked;
2126 //Dbprintf("New state created, nt=");
2127 }else if(!high_entropy_warning_issued){
2128 /**
2129 *If we wound up here, it means that the state table was eaten up by potential nonces. This could be fixed by
2130 *increasing the size of the state buffer, however, it points to some other problem. Ideally, we should get the same nonce
2131 *every time. Realistically we should get a few different nonces, but if we get more than 50, there is probably somehting
2132 *else that is wrong. An attack using too high nonce entropy will take **LONG** time to finish.
2133 */
2134 DbpString("WARNING: Nonce entropy is suspiciously high, something is wrong. Check timeouts (and perhaps increase STATE_SIZE)");
2135 high_entropy_warning_issued = 1;
2136 }
2137 }
2138 if(pState == NULL) continue;
2139
2140 int result = continueAttack(pState, receivedAnswer);
2141
2142 if(result == 1){
2143 //One state progressed another step
2144 if(pState->nt_diff > progress)
2145 {
2146 progress = pState->nt_diff;
2147 //Alert the user
2148 Dbprintf("Recovery progress: %d/8, NTs attacked: %d ", progress,nts_attacked );
2149 }
2150 //Dbprintf("State increased to %d in state %d", pState->nt_diff, i);
2151 }
2152 else if(result == 2){
2153 //Dbprintf("Continue attack no answer, par is now %d", pState->par);
2154 }
2155 else if(result == 0){
2156 reportResults(uid,pState,1);
2157 return;
2158 }
2159 }
2160 reportResults(uid,NULL,0);
2161 }
2162 //-----------------------------------------------------------------------------
2163 // MIFARE 1K simulate.
2164 //
2165 //-----------------------------------------------------------------------------
2166 void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain)
2167 {
2168 int cardSTATE = MFEMUL_NOFIELD;
2169 int _7BUID = 0;
2170 int vHf = 0; // in mV
2171 //int nextCycleTimeout = 0;
2172 int res;
2173 // uint32_t timer = 0;
2174 uint32_t selTimer = 0;
2175 uint32_t authTimer = 0;
2176 uint32_t par = 0;
2177 int len = 0;
2178 uint8_t cardWRBL = 0;
2179 uint8_t cardAUTHSC = 0;
2180 uint8_t cardAUTHKEY = 0xff; // no authentication
2181 //uint32_t cardRn = 0;
2182 uint32_t cardRr = 0;
2183 uint32_t cuid = 0;
2184 //uint32_t rn_enc = 0;
2185 uint32_t ans = 0;
2186 uint32_t cardINTREG = 0;
2187 uint8_t cardINTBLOCK = 0;
2188 struct Crypto1State mpcs = {0, 0};
2189 struct Crypto1State *pcs;
2190 pcs = &mpcs;
2191
2192 uint8_t* receivedCmd = eml_get_bigbufptr_recbuf();
2193 uint8_t *response = eml_get_bigbufptr_sendbuf();
2194
2195 static uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID
2196
2197 static uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62};
2198 static uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; // !!!
2199
2200 static uint8_t rSAK[] = {0x08, 0xb6, 0xdd};
2201 static uint8_t rSAK1[] = {0x04, 0xda, 0x17};
2202
2203 static uint8_t rAUTH_NT[] = {0x01, 0x02, 0x03, 0x04};
2204 // static uint8_t rAUTH_NT[] = {0x1a, 0xac, 0xff, 0x4f};
2205 static uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00};
2206
2207 // clear trace
2208 traceLen = 0;
2209 tracing = true;
2210
2211 // Authenticate response - nonce
2212 uint32_t nonce = bytes_to_num(rAUTH_NT, 4);
2213
2214 // get UID from emul memory
2215 emlGetMemBt(receivedCmd, 7, 1);
2216 _7BUID = !(receivedCmd[0] == 0x00);
2217 if (!_7BUID) { // ---------- 4BUID
2218 rATQA[0] = 0x04;
2219
2220 emlGetMemBt(rUIDBCC1, 0, 4);
2221 rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
2222 } else { // ---------- 7BUID
2223 rATQA[0] = 0x44;
2224
2225 rUIDBCC1[0] = 0x88;
2226 emlGetMemBt(&rUIDBCC1[1], 0, 3);
2227 rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
2228 emlGetMemBt(rUIDBCC2, 3, 4);
2229 rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3];
2230 }
2231
2232 // -------------------------------------- test area
2233
2234 // -------------------------------------- END test area
2235 // start mkseconds counter
2236 StartCountUS();
2237
2238 // We need to listen to the high-frequency, peak-detected path.
2239 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
2240 FpgaSetupSsc();
2241
2242 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
2243 SpinDelay(200);
2244
2245 if (MF_DBGLEVEL >= 1) Dbprintf("Started. 7buid=%d", _7BUID);
2246 // calibrate mkseconds counter
2247 GetDeltaCountUS();
2248 while (true) {
2249 WDT_HIT();
2250
2251 if(BUTTON_PRESS()) {
2252 break;
2253 }
2254
2255 // find reader field
2256 // Vref = 3300mV, and an 10:1 voltage divider on the input
2257 // can measure voltages up to 33000 mV
2258 if (cardSTATE == MFEMUL_NOFIELD) {
2259 vHf = (33000 * AvgAdc(ADC_CHAN_HF)) >> 10;
2260 if (vHf > MF_MINFIELDV) {
2261 cardSTATE_TO_IDLE();
2262 LED_A_ON();
2263 }
2264 }
2265
2266 if (cardSTATE != MFEMUL_NOFIELD) {
2267 res = EmGetCmd(receivedCmd, &len, RECV_CMD_SIZE); // (+ nextCycleTimeout)
2268 if (res == 2) {
2269 cardSTATE = MFEMUL_NOFIELD;
2270 LEDsoff();
2271 continue;
2272 }
2273 if(res) break;
2274 }
2275
2276 //nextCycleTimeout = 0;
2277
2278 // if (len) Dbprintf("len:%d cmd: %02x %02x %02x %02x", len, receivedCmd[0], receivedCmd[1], receivedCmd[2], receivedCmd[3]);
2279
2280 if (len != 4 && cardSTATE != MFEMUL_NOFIELD) { // len != 4 <---- speed up the code 4 authentication
2281 // REQ or WUP request in ANY state and WUP in HALTED state
2282 if (len == 1 && ((receivedCmd[0] == 0x26 && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == 0x52)) {
2283 selTimer = GetTickCount();
2284 EmSendCmdEx(rATQA, sizeof(rATQA), (receivedCmd[0] == 0x52));
2285 cardSTATE = MFEMUL_SELECT1;
2286
2287 // init crypto block
2288 LED_B_OFF();
2289 LED_C_OFF();
2290 crypto1_destroy(pcs);
2291 cardAUTHKEY = 0xff;
2292 }
2293 }
2294
2295 switch (cardSTATE) {
2296 case MFEMUL_NOFIELD:{
2297 break;
2298 }
2299 case MFEMUL_HALTED:{
2300 break;
2301 }
2302 case MFEMUL_IDLE:{
2303 break;
2304 }
2305 case MFEMUL_SELECT1:{
2306 // select all
2307 if (len == 2 && (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x20)) {
2308 EmSendCmd(rUIDBCC1, sizeof(rUIDBCC1));
2309 break;
2310 }
2311
2312 // select card
2313 if (len == 9 &&
2314 (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC1, 4) == 0)) {
2315 if (!_7BUID)
2316 EmSendCmd(rSAK, sizeof(rSAK));
2317 else
2318 EmSendCmd(rSAK1, sizeof(rSAK1));
2319
2320 cuid = bytes_to_num(rUIDBCC1, 4);
2321 if (!_7BUID) {
2322 cardSTATE = MFEMUL_WORK;
2323 LED_B_ON();
2324 if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol1 time: %d", GetTickCount() - selTimer);
2325 break;
2326 } else {
2327 cardSTATE = MFEMUL_SELECT2;
2328 break;
2329 }
2330 }
2331
2332 break;
2333 }
2334 case MFEMUL_SELECT2:{
2335 if (!len) break;
2336
2337 if (len == 2 && (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x20)) {
2338 EmSendCmd(rUIDBCC2, sizeof(rUIDBCC2));
2339 break;
2340 }
2341
2342 // select 2 card
2343 if (len == 9 &&
2344 (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC2, 4) == 0)) {
2345 EmSendCmd(rSAK, sizeof(rSAK));
2346
2347 cuid = bytes_to_num(rUIDBCC2, 4);
2348 cardSTATE = MFEMUL_WORK;
2349 LED_B_ON();
2350 if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol2 time: %d", GetTickCount() - selTimer);
2351 break;
2352 }
2353
2354 // i guess there is a command). go into the work state.
2355 if (len != 4) break;
2356 cardSTATE = MFEMUL_WORK;
2357 goto lbWORK;
2358 }
2359 case MFEMUL_AUTH1:{
2360 if (len == 8) {
2361 // --- crypto
2362 //rn_enc = bytes_to_num(receivedCmd, 4);
2363 //cardRn = rn_enc ^ crypto1_word(pcs, rn_enc , 1);
2364 cardRr = bytes_to_num(&receivedCmd[4], 4) ^ crypto1_word(pcs, 0, 0);
2365 // test if auth OK
2366 if (cardRr != prng_successor(nonce, 64)){
2367 if (MF_DBGLEVEL >= 4) Dbprintf("AUTH FAILED. cardRr=%08x, succ=%08x", cardRr, prng_successor(nonce, 64));
2368 cardSTATE_TO_IDLE();
2369 break;
2370 }
2371 ans = prng_successor(nonce, 96) ^ crypto1_word(pcs, 0, 0);
2372 num_to_bytes(ans, 4, rAUTH_AT);
2373 // --- crypto
2374 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
2375 cardSTATE = MFEMUL_AUTH2;
2376 } else {
2377 cardSTATE_TO_IDLE();
2378 }
2379 if (cardSTATE != MFEMUL_AUTH2) break;
2380 }
2381 case MFEMUL_AUTH2:{
2382 LED_C_ON();
2383 cardSTATE = MFEMUL_WORK;
2384 if (MF_DBGLEVEL >= 4) Dbprintf("AUTH COMPLETED. sec=%d, key=%d time=%d", cardAUTHSC, cardAUTHKEY, GetTickCount() - authTimer);
2385 break;
2386 }
2387 case MFEMUL_WORK:{
2388 lbWORK: if (len == 0) break;
2389
2390 if (cardAUTHKEY == 0xff) {
2391 // first authentication
2392 if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) {
2393 authTimer = GetTickCount();
2394
2395 cardAUTHSC = receivedCmd[1] / 4; // received block num
2396 cardAUTHKEY = receivedCmd[0] - 0x60;
2397
2398 // --- crypto
2399 crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
2400 ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0);
2401 num_to_bytes(nonce, 4, rAUTH_AT);
2402 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
2403 // --- crypto
2404
2405 // last working revision
2406 // EmSendCmd14443aRaw(resp1, resp1Len, 0);
2407 // LogTrace(NULL, 0, GetDeltaCountUS(), 0, true);
2408
2409 cardSTATE = MFEMUL_AUTH1;
2410 //nextCycleTimeout = 10;
2411 break;
2412 }
2413 } else {
2414 // decrypt seqence
2415 mf_crypto1_decrypt(pcs, receivedCmd, len);
2416
2417 // nested authentication
2418 if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) {
2419 authTimer = GetTickCount();
2420
2421 cardAUTHSC = receivedCmd[1] / 4; // received block num
2422 cardAUTHKEY = receivedCmd[0] - 0x60;
2423
2424 // --- crypto
2425 crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
2426 ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0);
2427 num_to_bytes(ans, 4, rAUTH_AT);
2428 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
2429 // --- crypto
2430
2431 cardSTATE = MFEMUL_AUTH1;
2432 //nextCycleTimeout = 10;
2433 break;
2434 }
2435 }
2436
2437 // rule 13 of 7.5.3. in ISO 14443-4. chaining shall be continued
2438 // BUT... ACK --> NACK
2439 if (len == 1 && receivedCmd[0] == CARD_ACK) {
2440 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2441 break;
2442 }
2443
2444 // rule 12 of 7.5.3. in ISO 14443-4. R(NAK) --> R(ACK)
2445 if (len == 1 && receivedCmd[0] == CARD_NACK_NA) {
2446 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2447 break;
2448 }
2449
2450 // read block
2451 if (len == 4 && receivedCmd[0] == 0x30) {
2452 if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
2453 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2454 break;
2455 }
2456 emlGetMem(response, receivedCmd[1], 1);
2457 AppendCrc14443a(response, 16);
2458 mf_crypto1_encrypt(pcs, response, 18, &par);
2459 EmSendCmdPar(response, 18, par);
2460 break;
2461 }
2462
2463 // write block
2464 if (len == 4 && receivedCmd[0] == 0xA0) {
2465 if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
2466 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2467 break;
2468 }
2469 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2470 //nextCycleTimeout = 50;
2471 cardSTATE = MFEMUL_WRITEBL2;
2472 cardWRBL = receivedCmd[1];
2473 break;
2474 }
2475
2476 // works with cardINTREG
2477
2478 // increment, decrement, restore
2479 if (len == 4 && (receivedCmd[0] == 0xC0 || receivedCmd[0] == 0xC1 || receivedCmd[0] == 0xC2)) {
2480 if (receivedCmd[1] >= 16 * 4 ||
2481 receivedCmd[1] / 4 != cardAUTHSC ||
2482 emlCheckValBl(receivedCmd[1])) {
2483 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2484 break;
2485 }
2486 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2487 if (receivedCmd[0] == 0xC1)
2488 cardSTATE = MFEMUL_INTREG_INC;
2489 if (receivedCmd[0] == 0xC0)
2490 cardSTATE = MFEMUL_INTREG_DEC;
2491 if (receivedCmd[0] == 0xC2)
2492 cardSTATE = MFEMUL_INTREG_REST;
2493 cardWRBL = receivedCmd[1];
2494
2495 break;
2496 }
2497
2498
2499 // transfer
2500 if (len == 4 && receivedCmd[0] == 0xB0) {
2501 if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
2502 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2503 break;
2504 }
2505
2506 if (emlSetValBl(cardINTREG, cardINTBLOCK, receivedCmd[1]))
2507 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2508 else
2509 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2510
2511 break;
2512 }
2513
2514 // halt
2515 if (len == 4 && (receivedCmd[0] == 0x50 && receivedCmd[1] == 0x00)) {
2516 LED_B_OFF();
2517 LED_C_OFF();
2518 cardSTATE = MFEMUL_HALTED;
2519 if (MF_DBGLEVEL >= 4) Dbprintf("--> HALTED. Selected time: %d ms", GetTickCount() - selTimer);
2520 break;
2521 }
2522
2523 // command not allowed
2524 if (len == 4) {
2525 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2526 break;
2527 }
2528
2529 // case break
2530 break;
2531 }
2532 case MFEMUL_WRITEBL2:{
2533 if (len == 18){
2534 mf_crypto1_decrypt(pcs, receivedCmd, len);
2535 emlSetMem(receivedCmd, cardWRBL, 1);
2536 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2537 cardSTATE = MFEMUL_WORK;
2538 break;
2539 } else {
2540 cardSTATE_TO_IDLE();
2541 break;
2542 }
2543 break;
2544 }
2545
2546 case MFEMUL_INTREG_INC:{
2547 mf_crypto1_decrypt(pcs, receivedCmd, len);
2548 memcpy(&ans, receivedCmd, 4);
2549 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
2550 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2551 cardSTATE_TO_IDLE();
2552 break;
2553 }
2554 cardINTREG = cardINTREG + ans;
2555 cardSTATE = MFEMUL_WORK;
2556 break;
2557 }
2558 case MFEMUL_INTREG_DEC:{
2559 mf_crypto1_decrypt(pcs, receivedCmd, len);
2560 memcpy(&ans, receivedCmd, 4);
2561 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
2562 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2563 cardSTATE_TO_IDLE();
2564 break;
2565 }
2566 cardINTREG = cardINTREG - ans;
2567 cardSTATE = MFEMUL_WORK;
2568 break;
2569 }
2570 case MFEMUL_INTREG_REST:{
2571 mf_crypto1_decrypt(pcs, receivedCmd, len);
2572 memcpy(&ans, receivedCmd, 4);
2573 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
2574 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2575 cardSTATE_TO_IDLE();
2576 break;
2577 }
2578 cardSTATE = MFEMUL_WORK;
2579 break;
2580 }
2581 }
2582 }
2583
2584 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
2585 LEDsoff();
2586
2587 // add trace trailer
2588 memset(rAUTH_NT, 0x44, 4);
2589 LogTrace(rAUTH_NT, 4, 0, 0, TRUE);
2590
2591 if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, traceLen);
2592 }
2593
2594 //-----------------------------------------------------------------------------
2595 // MIFARE sniffer.
2596 //
2597 //-----------------------------------------------------------------------------
2598 void RAMFUNC SniffMifare(uint8_t param) {
2599 // param:
2600 // bit 0 - trigger from first card answer
2601 // bit 1 - trigger from first reader 7-bit request
2602
2603 // C(red) A(yellow) B(green)
2604 LEDsoff();
2605 // init trace buffer
2606 iso14a_clear_trace();
2607
2608 // The command (reader -> tag) that we're receiving.
2609 // The length of a received command will in most cases be no more than 18 bytes.
2610 // So 32 should be enough!
2611 uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
2612 // The response (tag -> reader) that we're receiving.
2613 uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET);
2614
2615 // As we receive stuff, we copy it from receivedCmd or receivedResponse
2616 // into trace, along with its length and other annotations.
2617 //uint8_t *trace = (uint8_t *)BigBuf;
2618
2619 // The DMA buffer, used to stream samples from the FPGA
2620 int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET;
2621 int8_t *data = dmaBuf;
2622 int maxDataLen = 0;
2623 int dataLen = 0;
2624
2625 // Set up the demodulator for tag -> reader responses.
2626 Demod.output = receivedResponse;
2627 Demod.len = 0;
2628 Demod.state = DEMOD_UNSYNCD;
2629
2630 // Set up the demodulator for the reader -> tag commands
2631 memset(&Uart, 0, sizeof(Uart));
2632 Uart.output = receivedCmd;
2633 Uart.byteCntMax = 32; // was 100 (greg)//////////////////
2634 Uart.state = STATE_UNSYNCD;
2635
2636 // Setup for the DMA.
2637 FpgaSetupSsc();
2638 FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
2639
2640 // And put the FPGA in the appropriate mode
2641 // Signal field is off with the appropriate LED
2642 LED_D_OFF();
2643 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER);
2644 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
2645
2646 // init sniffer
2647 MfSniffInit();
2648 int sniffCounter = 0;
2649
2650 // And now we loop, receiving samples.
2651 while(true) {
2652 if(BUTTON_PRESS()) {
2653 DbpString("cancelled by button");
2654 goto done;
2655 }
2656
2657 LED_A_ON();
2658 WDT_HIT();
2659
2660 if (++sniffCounter > 65) {
2661 if (MfSniffSend(2000)) {
2662 FpgaEnableSscDma();
2663 }
2664 sniffCounter = 0;
2665 }
2666
2667 int register readBufDataP = data - dmaBuf;
2668 int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR;
2669 if (readBufDataP <= dmaBufDataP){
2670 dataLen = dmaBufDataP - readBufDataP;
2671 } else {
2672 dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP + 1;
2673 }
2674 // test for length of buffer
2675 if(dataLen > maxDataLen) {
2676 maxDataLen = dataLen;
2677 if(dataLen > 400) {
2678 Dbprintf("blew circular buffer! dataLen=0x%x", dataLen);
2679 goto done;
2680 }
2681 }
2682 if(dataLen < 1) continue;
2683
2684 // primary buffer was stopped( <-- we lost data!
2685 if (!AT91C_BASE_PDC_SSC->PDC_RCR) {
2686 AT91C_BASE_PDC_SSC->PDC_RPR = (uint32_t) dmaBuf;
2687 AT91C_BASE_PDC_SSC->PDC_RCR = DMA_BUFFER_SIZE;
2688 Dbprintf("RxEmpty ERROR!!! data length:%d", dataLen); // temporary
2689 }
2690 // secondary buffer sets as primary, secondary buffer was stopped
2691 if (!AT91C_BASE_PDC_SSC->PDC_RNCR) {
2692 AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf;
2693 AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
2694 }
2695
2696 LED_A_OFF();
2697
2698 if(MillerDecoding((data[0] & 0xF0) >> 4)) {
2699 LED_C_INV();
2700 // check - if there is a short 7bit request from reader
2701 if (MfSniffLogic(receivedCmd, Uart.byteCnt, Uart.parityBits, Uart.bitCnt, TRUE)) break;
2702
2703 /* And ready to receive another command. */
2704 Uart.state = STATE_UNSYNCD;
2705
2706 /* And also reset the demod code */
2707 Demod.state = DEMOD_UNSYNCD;
2708 }
2709
2710 if(ManchesterDecoding(data[0] & 0x0F)) {
2711 LED_C_INV();
2712
2713 if (MfSniffLogic(receivedResponse, Demod.len, Demod.parityBits, Demod.bitCount, FALSE)) break;
2714
2715 // And ready to receive another response.
2716 memset(&Demod, 0, sizeof(Demod));
2717 Demod.output = receivedResponse;
2718 Demod.state = DEMOD_UNSYNCD;
2719
2720 /* And also reset the uart code */
2721 Uart.state = STATE_UNSYNCD;
2722 }
2723
2724 data++;
2725 if(data > dmaBuf + DMA_BUFFER_SIZE) {
2726 data = dmaBuf;
2727 }
2728 } // main cycle
2729
2730 DbpString("COMMAND FINISHED");
2731
2732 done:
2733 FpgaDisableSscDma();
2734 MfSniffEnd();
2735
2736 Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.byteCnt=%x Uart.byteCntMax=%x", maxDataLen, Uart.state, Uart.byteCnt, Uart.byteCntMax);
2737 LEDsoff();
2738 }
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