]> git.zerfleddert.de Git - proxmark3-svn/blob - armsrc/iso14443a.c
projects / proxmark3-svn / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Some documentation improvement
[proxmark3-svn] / armsrc / iso14443a.c
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 // prepare a delayed transfer. This simply shifts ToSend[] by a number
1223 // of bits specified in the delay parameter.
1224 void PrepareDelayedTransfer(uint16_t delay)
1225 {
1226 uint8_t bitmask = 0;
1227 uint8_t bits_to_shift = 0;
1228 uint8_t bits_shifted = 0;
1229
1230 delay &= 0x07;
1231 if (delay) {
1232 for (uint16_t i = 0; i < delay; i++) {
1233 bitmask |= (0x01 << i);
1234 }
1235 ToSend[++ToSendMax] = 0x00;
1236 for (uint16_t i = 0; i < ToSendMax; i++) {
1237 bits_to_shift = ToSend[i] & bitmask;
1238 ToSend[i] = ToSend[i] >> delay;
1239 ToSend[i] = ToSend[i] | (bits_shifted << (8 - delay));
1240 bits_shifted = bits_to_shift;
1241 }
1242 }
1243 }
1244
1245
1246
1247
1248 //-----------------------------------------------------------------------------
1249 // Transmit the command (to the tag) that was placed in ToSend[].
1250 // Parameter timing:
1251 // if NULL: ignored
1252 // if == 0: return time of transfer
1253 // if != 0: delay transfer until time specified
1254 //-----------------------------------------------------------------------------
1255 static void TransmitFor14443a(const uint8_t *cmd, int len, uint32_t *timing)
1256 {
1257 int c;
1258
1259 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1260
1261
1262 if (timing) {
1263 if(*timing == 0) { // Measure time
1264 *timing = (GetCountMifare() + 8) & 0xfffffff8;
1265 } else {
1266 PrepareDelayedTransfer(*timing & 0x00000007); // Delay transfer (fine tuning - up to 7 MF clock ticks)
1267 }
1268 if(MF_DBGLEVEL >= 4 && GetCountMifare() >= (*timing & 0xfffffff8)) Dbprintf("TransmitFor14443a: Missed timing");
1269 while(GetCountMifare() < (*timing & 0xfffffff8)); // Delay transfer (multiple of 8 MF clock ticks)
1270 }
1271
1272 for(c = 0; c < 10;) { // standard delay for each transfer (allow tag to be ready after last transmission)
1273 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1274 AT91C_BASE_SSC->SSC_THR = 0x00;
1275 c++;
1276 }
1277 }
1278
1279 c = 0;
1280 for(;;) {
1281 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1282 AT91C_BASE_SSC->SSC_THR = cmd[c];
1283 c++;
1284 if(c >= len) {
1285 break;
1286 }
1287 }
1288 }
1289
1290 }
1291
1292 //-----------------------------------------------------------------------------
1293 // Prepare reader command (in bits, support short frames) to send to FPGA
1294 //-----------------------------------------------------------------------------
1295 void CodeIso14443aBitsAsReaderPar(const uint8_t * cmd, int bits, uint32_t dwParity)
1296 {
1297 int i, j;
1298 int last;
1299 uint8_t b;
1300
1301 ToSendReset();
1302
1303 // Start of Communication (Seq. Z)
1304 ToSend[++ToSendMax] = SEC_Z;
1305 last = 0;
1306
1307 size_t bytecount = nbytes(bits);
1308 // Generate send structure for the data bits
1309 for (i = 0; i < bytecount; i++) {
1310 // Get the current byte to send
1311 b = cmd[i];
1312 size_t bitsleft = MIN((bits-(i*8)),8);
1313
1314 for (j = 0; j < bitsleft; j++) {
1315 if (b & 1) {
1316 // Sequence X
1317 ToSend[++ToSendMax] = SEC_X;
1318 last = 1;
1319 } else {
1320 if (last == 0) {
1321 // Sequence Z
1322 ToSend[++ToSendMax] = SEC_Z;
1323 } else {
1324 // Sequence Y
1325 ToSend[++ToSendMax] = SEC_Y;
1326 last = 0;
1327 }
1328 }
1329 b >>= 1;
1330 }
1331
1332 // Only transmit (last) parity bit if we transmitted a complete byte
1333 if (j == 8) {
1334 // Get the parity bit
1335 if ((dwParity >> i) & 0x01) {
1336 // Sequence X
1337 ToSend[++ToSendMax] = SEC_X;
1338 last = 1;
1339 } else {
1340 if (last == 0) {
1341 // Sequence Z
1342 ToSend[++ToSendMax] = SEC_Z;
1343 } else {
1344 // Sequence Y
1345 ToSend[++ToSendMax] = SEC_Y;
1346 last = 0;
1347 }
1348 }
1349 }
1350 }
1351
1352 // End of Communication
1353 if (last == 0) {
1354 // Sequence Z
1355 ToSend[++ToSendMax] = SEC_Z;
1356 } else {
1357 // Sequence Y
1358 ToSend[++ToSendMax] = SEC_Y;
1359 last = 0;
1360 }
1361 // Sequence Y
1362 ToSend[++ToSendMax] = SEC_Y;
1363
1364 // Just to be sure!
1365 ToSend[++ToSendMax] = SEC_Y;
1366 ToSend[++ToSendMax] = SEC_Y;
1367 ToSend[++ToSendMax] = SEC_Y;
1368
1369 // Convert from last character reference to length
1370 ToSendMax++;
1371 }
1372
1373 //-----------------------------------------------------------------------------
1374 // Prepare reader command to send to FPGA
1375 //-----------------------------------------------------------------------------
1376 void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
1377 {
1378 CodeIso14443aBitsAsReaderPar(cmd,len*8,dwParity);
1379 }
1380
1381 //-----------------------------------------------------------------------------
1382 // Wait for commands from reader
1383 // Stop when button is pressed (return 1) or field was gone (return 2)
1384 // Or return 0 when command is captured
1385 //-----------------------------------------------------------------------------
1386 static int EmGetCmd(uint8_t *received, int *len, int maxLen)
1387 {
1388 *len = 0;
1389
1390 uint32_t timer = 0, vtime = 0;
1391 int analogCnt = 0;
1392 int analogAVG = 0;
1393
1394 // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
1395 // only, since we are receiving, not transmitting).
1396 // Signal field is off with the appropriate LED
1397 LED_D_OFF();
1398 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
1399
1400 // Set ADC to read field strength
1401 AT91C_BASE_ADC->ADC_CR = AT91C_ADC_SWRST;
1402 AT91C_BASE_ADC->ADC_MR =
1403 ADC_MODE_PRESCALE(32) |
1404 ADC_MODE_STARTUP_TIME(16) |
1405 ADC_MODE_SAMPLE_HOLD_TIME(8);
1406 AT91C_BASE_ADC->ADC_CHER = ADC_CHANNEL(ADC_CHAN_HF);
1407 // start ADC
1408 AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
1409
1410 // Now run a 'software UART' on the stream of incoming samples.
1411 Uart.output = received;
1412 Uart.byteCntMax = maxLen;
1413 Uart.state = STATE_UNSYNCD;
1414
1415 for(;;) {
1416 WDT_HIT();
1417
1418 if (BUTTON_PRESS()) return 1;
1419
1420 // test if the field exists
1421 if (AT91C_BASE_ADC->ADC_SR & ADC_END_OF_CONVERSION(ADC_CHAN_HF)) {
1422 analogCnt++;
1423 analogAVG += AT91C_BASE_ADC->ADC_CDR[ADC_CHAN_HF];
1424 AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
1425 if (analogCnt >= 32) {
1426 if ((33000 * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) {
1427 vtime = GetTickCount();
1428 if (!timer) timer = vtime;
1429 // 50ms no field --> card to idle state
1430 if (vtime - timer > 50) return 2;
1431 } else
1432 if (timer) timer = 0;
1433 analogCnt = 0;
1434 analogAVG = 0;
1435 }
1436 }
1437 // transmit none
1438 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1439 AT91C_BASE_SSC->SSC_THR = 0x00;
1440 }
1441 // receive and test the miller decoding
1442 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1443 volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1444 if(MillerDecoding((b & 0xf0) >> 4)) {
1445 *len = Uart.byteCnt;
1446 if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE);
1447 return 0;
1448 }
1449 if(MillerDecoding(b & 0x0f)) {
1450 *len = Uart.byteCnt;
1451 if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE);
1452 return 0;
1453 }
1454 }
1455 }
1456 }
1457
1458 static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded)
1459 {
1460 int i, u = 0;
1461 uint8_t b = 0;
1462
1463 // Modulate Manchester
1464 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD);
1465 AT91C_BASE_SSC->SSC_THR = 0x00;
1466 FpgaSetupSsc();
1467
1468 // include correction bit
1469 i = 1;
1470 if((Uart.parityBits & 0x01) || correctionNeeded) {
1471 // 1236, so correction bit needed
1472 i = 0;
1473 }
1474
1475 // send cycle
1476 for(;;) {
1477 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1478 volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1479 (void)b;
1480 }
1481 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1482 if(i > respLen) {
1483 b = 0xff; // was 0x00
1484 u++;
1485 } else {
1486 b = resp[i];
1487 i++;
1488 }
1489 AT91C_BASE_SSC->SSC_THR = b;
1490
1491 if(u > 4) break;
1492 }
1493 if(BUTTON_PRESS()) {
1494 break;
1495 }
1496 }
1497
1498 return 0;
1499 }
1500
1501 int EmSend4bitEx(uint8_t resp, int correctionNeeded){
1502 Code4bitAnswerAsTag(resp);
1503 int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded);
1504 if (tracing) LogTrace(&resp, 1, GetDeltaCountUS(), GetParity(&resp, 1), FALSE);
1505 return res;
1506 }
1507
1508 int EmSend4bit(uint8_t resp){
1509 return EmSend4bitEx(resp, 0);
1510 }
1511
1512 int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par){
1513 CodeIso14443aAsTagPar(resp, respLen, par);
1514 int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded);
1515 if (tracing) LogTrace(resp, respLen, GetDeltaCountUS(), par, FALSE);
1516 return res;
1517 }
1518
1519 int EmSendCmdEx(uint8_t *resp, int respLen, int correctionNeeded){
1520 return EmSendCmdExPar(resp, respLen, correctionNeeded, GetParity(resp, respLen));
1521 }
1522
1523 int EmSendCmd(uint8_t *resp, int respLen){
1524 return EmSendCmdExPar(resp, respLen, 0, GetParity(resp, respLen));
1525 }
1526
1527 int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par){
1528 return EmSendCmdExPar(resp, respLen, 0, par);
1529 }
1530
1531 //-----------------------------------------------------------------------------
1532 // Wait a certain time for tag response
1533 // If a response is captured return TRUE
1534 // If it takes to long return FALSE
1535 //-----------------------------------------------------------------------------
1536 static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer
1537 {
1538 // buffer needs to be 512 bytes
1539 int c;
1540
1541 // Set FPGA mode to "reader listen mode", no modulation (listen
1542 // only, since we are receiving, not transmitting).
1543 // Signal field is on with the appropriate LED
1544 LED_D_ON();
1545 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);
1546
1547 // Now get the answer from the card
1548 Demod.output = receivedResponse;
1549 Demod.len = 0;
1550 Demod.state = DEMOD_UNSYNCD;
1551
1552 uint8_t b;
1553 if (elapsed) *elapsed = 0;
1554
1555 c = 0;
1556 for(;;) {
1557 WDT_HIT();
1558
1559 // if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1560 // AT91C_BASE_SSC->SSC_THR = 0x00; // To make use of exact timing of next command from reader!!
1561 // if (elapsed) (*elapsed)++;
1562 // }
1563 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1564 if(c < iso14a_timeout) { c++; } else { return FALSE; }
1565 b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1566 if(ManchesterDecoding((b>>4) & 0xf)) {
1567 *samples = ((c - 1) << 3) + 4;
1568 return TRUE;
1569 }
1570 if(ManchesterDecoding(b & 0x0f)) {
1571 *samples = c << 3;
1572 return TRUE;
1573 }
1574 }
1575 }
1576 }
1577
1578 void ReaderTransmitBitsPar(uint8_t* frame, int bits, uint32_t par, uint32_t *timing)
1579 {
1580
1581 CodeIso14443aBitsAsReaderPar(frame,bits,par);
1582
1583 // Select the card
1584 TransmitFor14443a(ToSend, ToSendMax, timing);
1585 if(trigger)
1586 LED_A_ON();
1587
1588 // Store reader command in buffer
1589 if (tracing) LogTrace(frame,nbytes(bits),0,par,TRUE);
1590 }
1591
1592 void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par, uint32_t *timing)
1593 {
1594 ReaderTransmitBitsPar(frame,len*8,par, timing);
1595 }
1596
1597 void ReaderTransmit(uint8_t* frame, int len, uint32_t *timing)
1598 {
1599 // Generate parity and redirect
1600 ReaderTransmitBitsPar(frame,len*8,GetParity(frame,len), timing);
1601 }
1602
1603 int ReaderReceive(uint8_t* receivedAnswer)
1604 {
1605 int samples = 0;
1606 if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE;
1607 if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE);
1608 if(samples == 0) return FALSE;
1609 return Demod.len;
1610 }
1611
1612 int ReaderReceivePar(uint8_t* receivedAnswer, uint32_t * parptr)
1613 {
1614 int samples = 0;
1615 if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE;
1616 if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE);
1617 *parptr = Demod.parityBits;
1618 if(samples == 0) return FALSE;
1619 return Demod.len;
1620 }
1621
1622 /* performs iso14443a anticolision procedure
1623 * fills the uid pointer unless NULL
1624 * fills resp_data unless NULL */
1625 int iso14443a_select_card(byte_t* uid_ptr, iso14a_card_select_t* p_hi14a_card, uint32_t* cuid_ptr) {
1626 uint8_t wupa[] = { 0x52 }; // 0x26 - REQA 0x52 - WAKE-UP
1627 uint8_t sel_all[] = { 0x93,0x20 };
1628 uint8_t sel_uid[] = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
1629 uint8_t rats[] = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0
1630 uint8_t* resp = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); // was 3560 - tied to other size changes
1631 byte_t uid_resp[4];
1632 size_t uid_resp_len;
1633
1634 uint8_t sak = 0x04; // cascade uid
1635 int cascade_level = 0;
1636 int len;
1637
1638 // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
1639 ReaderTransmitBitsPar(wupa,7,0, NULL);
1640 // Receive the ATQA
1641 if(!ReaderReceive(resp)) return 0;
1642 // Dbprintf("atqa: %02x %02x",resp[0],resp[1]);
1643
1644 if(p_hi14a_card) {
1645 memcpy(p_hi14a_card->atqa, resp, 2);
1646 p_hi14a_card->uidlen = 0;
1647 memset(p_hi14a_card->uid,0,10);
1648 }
1649
1650 // clear uid
1651 if (uid_ptr) {
1652 memset(uid_ptr,0,10);
1653 }
1654
1655 // OK we will select at least at cascade 1, lets see if first byte of UID was 0x88 in
1656 // which case we need to make a cascade 2 request and select - this is a long UID
1657 // While the UID is not complete, the 3nd bit (from the right) is set in the SAK.
1658 for(; sak & 0x04; cascade_level++) {
1659 // SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97)
1660 sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2;
1661
1662 // SELECT_ALL
1663 ReaderTransmit(sel_all,sizeof(sel_all), NULL);
1664 if (!ReaderReceive(resp)) return 0;
1665
1666 // First backup the current uid
1667 memcpy(uid_resp,resp,4);
1668 uid_resp_len = 4;
1669 // Dbprintf("uid: %02x %02x %02x %02x",uid_resp[0],uid_resp[1],uid_resp[2],uid_resp[3]);
1670
1671 // calculate crypto UID. Always use last 4 Bytes.
1672 if(cuid_ptr) {
1673 *cuid_ptr = bytes_to_num(uid_resp, 4);
1674 }
1675
1676 // Construct SELECT UID command
1677 memcpy(sel_uid+2,resp,5);
1678 AppendCrc14443a(sel_uid,7);
1679 ReaderTransmit(sel_uid,sizeof(sel_uid), NULL);
1680
1681 // Receive the SAK
1682 if (!ReaderReceive(resp)) return 0;
1683 sak = resp[0];
1684
1685 // Test if more parts of the uid are comming
1686 if ((sak & 0x04) && uid_resp[0] == 0x88) {
1687 // Remove first byte, 0x88 is not an UID byte, it CT, see page 3 of:
1688 // http://www.nxp.com/documents/application_note/AN10927.pdf
1689 memcpy(uid_resp, uid_resp + 1, 3);
1690 uid_resp_len = 3;
1691 }
1692
1693 if(uid_ptr) {
1694 memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
1695 }
1696
1697 if(p_hi14a_card) {
1698 memcpy(p_hi14a_card->uid + (cascade_level*3), uid_resp, uid_resp_len);
1699 p_hi14a_card->uidlen += uid_resp_len;
1700 }
1701 }
1702
1703 if(p_hi14a_card) {
1704 p_hi14a_card->sak = sak;
1705 p_hi14a_card->ats_len = 0;
1706 }
1707
1708 if( (sak & 0x20) == 0) {
1709 return 2; // non iso14443a compliant tag
1710 }
1711
1712 // Request for answer to select
1713 AppendCrc14443a(rats, 2);
1714 ReaderTransmit(rats, sizeof(rats), NULL);
1715
1716 if (!(len = ReaderReceive(resp))) return 0;
1717
1718 if(p_hi14a_card) {
1719 memcpy(p_hi14a_card->ats, resp, sizeof(p_hi14a_card->ats));
1720 p_hi14a_card->ats_len = len;
1721 }
1722
1723 // reset the PCB block number
1724 iso14_pcb_blocknum = 0;
1725 return 1;
1726 }
1727
1728 void iso14443a_setup() {
1729 // Set up the synchronous serial port
1730 FpgaSetupSsc();
1731 // Start from off (no field generated)
1732 // Signal field is off with the appropriate LED
1733 // LED_D_OFF();
1734 // FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1735 // SpinDelay(50);
1736
1737 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
1738
1739 // Now give it time to spin up.
1740 // Signal field is on with the appropriate LED
1741 LED_D_ON();
1742 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1743 SpinDelay(7); // iso14443-3 specifies 5ms max.
1744
1745 iso14a_timeout = 2048; //default
1746 }
1747
1748 int iso14_apdu(uint8_t * cmd, size_t cmd_len, void * data) {
1749 uint8_t real_cmd[cmd_len+4];
1750 real_cmd[0] = 0x0a; //I-Block
1751 // put block number into the PCB
1752 real_cmd[0] |= iso14_pcb_blocknum;
1753 real_cmd[1] = 0x00; //CID: 0 //FIXME: allow multiple selected cards
1754 memcpy(real_cmd+2, cmd, cmd_len);
1755 AppendCrc14443a(real_cmd,cmd_len+2);
1756
1757 ReaderTransmit(real_cmd, cmd_len+4, NULL);
1758 size_t len = ReaderReceive(data);
1759 uint8_t * data_bytes = (uint8_t *) data;
1760 if (!len)
1761 return 0; //DATA LINK ERROR
1762 // if we received an I- or R(ACK)-Block with a block number equal to the
1763 // current block number, toggle the current block number
1764 else if (len >= 4 // PCB+CID+CRC = 4 bytes
1765 && ((data_bytes[0] & 0xC0) == 0 // I-Block
1766 || (data_bytes[0] & 0xD0) == 0x80) // R-Block with ACK bit set to 0
1767 && (data_bytes[0] & 0x01) == iso14_pcb_blocknum) // equal block numbers
1768 {
1769 iso14_pcb_blocknum ^= 1;
1770 }
1771
1772 return len;
1773 }
1774
1775 //-----------------------------------------------------------------------------
1776 // Read an ISO 14443a tag. Send out commands and store answers.
1777 //
1778 //-----------------------------------------------------------------------------
1779 void ReaderIso14443a(UsbCommand * c)
1780 {
1781 iso14a_command_t param = c->arg[0];
1782 uint8_t * cmd = c->d.asBytes;
1783 size_t len = c->arg[1];
1784 size_t lenbits = c->arg[2];
1785 uint32_t arg0 = 0;
1786 byte_t buf[USB_CMD_DATA_SIZE];
1787
1788 if(param & ISO14A_CONNECT) {
1789 iso14a_clear_trace();
1790 }
1791 iso14a_set_tracing(true);
1792
1793 if(param & ISO14A_REQUEST_TRIGGER) {
1794 iso14a_set_trigger(1);
1795 }
1796
1797 if(param & ISO14A_CONNECT) {
1798 iso14443a_setup();
1799 if(!(param & ISO14A_NO_SELECT)) {
1800 iso14a_card_select_t *card = (iso14a_card_select_t*)buf;
1801 arg0 = iso14443a_select_card(NULL,card,NULL);
1802 cmd_send(CMD_ACK,arg0,card->uidlen,0,buf,sizeof(iso14a_card_select_t));
1803 }
1804 }
1805
1806 if(param & ISO14A_SET_TIMEOUT) {
1807 iso14a_timeout = c->arg[2];
1808 }
1809
1810 if(param & ISO14A_SET_TIMEOUT) {
1811 iso14a_timeout = c->arg[2];
1812 }
1813
1814 if(param & ISO14A_APDU) {
1815 arg0 = iso14_apdu(cmd, len, buf);
1816 cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
1817 }
1818
1819 if(param & ISO14A_RAW) {
1820 if(param & ISO14A_APPEND_CRC) {
1821 AppendCrc14443a(cmd,len);
1822 len += 2;
1823 }
1824 if(lenbits>0) {
1825 ReaderTransmitBitsPar(cmd,lenbits,GetParity(cmd,lenbits/8), NULL);
1826 } else {
1827 ReaderTransmit(cmd,len, NULL);
1828 }
1829 arg0 = ReaderReceive(buf);
1830 cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
1831 }
1832
1833 if(param & ISO14A_REQUEST_TRIGGER) {
1834 iso14a_set_trigger(0);
1835 }
1836
1837 if(param & ISO14A_NO_DISCONNECT) {
1838 return;
1839 }
1840
1841 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1842 LEDsoff();
1843 }
1844
1845
1846 // Determine the distance between two nonces.
1847 // Assume that the difference is small, but we don't know which is first.
1848 // Therefore try in alternating directions.
1849 int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
1850
1851 uint16_t i;
1852 uint32_t nttmp1, nttmp2;
1853
1854 if (nt1 == nt2) return 0;
1855
1856 nttmp1 = nt1;
1857 nttmp2 = nt2;
1858
1859 for (i = 1; i < 32768; i++) {
1860 nttmp1 = prng_successor(nttmp1, 1);
1861 if (nttmp1 == nt2) return i;
1862 nttmp2 = prng_successor(nttmp2, 1);
1863 if (nttmp2 == nt1) return -i;
1864 }
1865
1866 return(-99999); // either nt1 or nt2 are invalid nonces
1867 }
1868
1869
1870 //-----------------------------------------------------------------------------
1871 // Recover several bits of the cypher stream. This implements (first stages of)
1872 // the algorithm described in "The Dark Side of Security by Obscurity and
1873 // Cloning MiFare Classic Rail and Building Passes, Anywhere, Anytime"
1874 // (article by Nicolas T. Courtois, 2009)
1875 //-----------------------------------------------------------------------------
1876 void ReaderMifare(bool first_try)
1877 {
1878 // Mifare AUTH
1879 uint8_t mf_auth[] = { 0x60,0x00,0xf5,0x7b };
1880 uint8_t mf_nr_ar[] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
1881 static uint8_t mf_nr_ar3;
1882
1883 uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);
1884 traceLen = 0;
1885 tracing = false;
1886
1887 byte_t nt_diff = 0;
1888 byte_t par = 0;
1889 //byte_t par_mask = 0xff;
1890 static byte_t par_low = 0;
1891 bool led_on = TRUE;
1892 uint8_t uid[10];
1893 uint32_t cuid;
1894
1895 uint32_t nt, previous_nt;
1896 static uint32_t nt_attacked = 0;
1897 byte_t par_list[8] = {0,0,0,0,0,0,0,0};
1898 byte_t ks_list[8] = {0,0,0,0,0,0,0,0};
1899
1900 static uint32_t sync_time;
1901 static uint32_t sync_cycles;
1902 int catch_up_cycles = 0;
1903 int last_catch_up = 0;
1904 uint16_t consecutive_resyncs = 0;
1905 int isOK = 0;
1906
1907
1908
1909 if (first_try) {
1910 StartCountMifare();
1911 mf_nr_ar3 = 0;
1912 iso14443a_setup();
1913 while((GetCountMifare() & 0xffff0000) != 0x10000); // wait for counter to reset and "warm up"
1914 sync_time = GetCountMifare() & 0xfffffff8;
1915 sync_cycles = 65536; // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).
1916 nt_attacked = 0;
1917 nt = 0;
1918 par = 0;
1919 }
1920 else {
1921 // we were unsuccessful on a previous call. Try another READER nonce (first 3 parity bits remain the same)
1922 // nt_attacked = prng_successor(nt_attacked, 1);
1923 mf_nr_ar3++;
1924 mf_nr_ar[3] = mf_nr_ar3;
1925 par = par_low;
1926 }
1927
1928 LED_A_ON();
1929 LED_B_OFF();
1930 LED_C_OFF();
1931
1932
1933 for(uint16_t i = 0; TRUE; i++) {
1934
1935 WDT_HIT();
1936
1937 // Test if the action was cancelled
1938 if(BUTTON_PRESS()) {
1939 break;
1940 }
1941
1942 LED_C_ON();
1943
1944 if(!iso14443a_select_card(uid, NULL, &cuid)) {
1945 if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Can't select card");
1946 continue;
1947 }
1948
1949 //keep the card active
1950 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1951
1952 // CodeIso14443aBitsAsReaderPar(mf_auth, sizeof(mf_auth)*8, GetParity(mf_auth, sizeof(mf_auth)*8));
1953
1954 sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles;
1955 catch_up_cycles = 0;
1956
1957 // if we missed the sync time already, advance to the next nonce repeat
1958 while(GetCountMifare() > sync_time) {
1959 sync_time = (sync_time & 0xfffffff8) + sync_cycles;
1960 }
1961
1962 // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked)
1963 ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
1964
1965 // Receive the (4 Byte) "random" nonce
1966 if (!ReaderReceive(receivedAnswer)) {
1967 if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Couldn't receive tag nonce");
1968 continue;
1969 }
1970
1971 previous_nt = nt;
1972 nt = bytes_to_num(receivedAnswer, 4);
1973
1974 // Transmit reader nonce with fake par
1975 ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar), par, NULL);
1976
1977 if (first_try && previous_nt && !nt_attacked) { // we didn't calibrate our clock yet
1978 int nt_distance = dist_nt(previous_nt, nt);
1979 if (nt_distance == 0) {
1980 nt_attacked = nt;
1981 }
1982 else {
1983 if (nt_distance == -99999) { // invalid nonce received, try again
1984 continue;
1985 }
1986 sync_cycles = (sync_cycles - nt_distance);
1987 if (MF_DBGLEVEL >= 3) Dbprintf("calibrating in cycle %d. nt_distance=%d, Sync_cycles: %d\n", i, nt_distance, sync_cycles);
1988 continue;
1989 }
1990 }
1991
1992 if ((nt != nt_attacked) && nt_attacked) { // we somehow lost sync. Try to catch up again...
1993 catch_up_cycles = -dist_nt(nt_attacked, nt);
1994 if (catch_up_cycles == 99999) { // invalid nonce received. Don't resync on that one.
1995 catch_up_cycles = 0;
1996 continue;
1997 }
1998 if (catch_up_cycles == last_catch_up) {
1999 consecutive_resyncs++;
2000 }
2001 else {
2002 last_catch_up = catch_up_cycles;
2003 consecutive_resyncs = 0;
2004 }
2005 if (consecutive_resyncs < 3) {
2006 if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d. nt_distance=%d. Consecutive Resyncs = %d. Trying one time catch up...\n", i, -catch_up_cycles, consecutive_resyncs);
2007 }
2008 else {
2009 sync_cycles = sync_cycles + catch_up_cycles;
2010 if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d for the fourth time consecutively (nt_distance = %d). Adjusting sync_cycles to %d.\n", i, -catch_up_cycles, sync_cycles);
2011 }
2012 continue;
2013 }
2014
2015 consecutive_resyncs = 0;
2016
2017 // Receive answer. This will be a 4 Bit NACK when the 8 parity bits are OK after decoding
2018 if (ReaderReceive(receivedAnswer))
2019 {
2020 catch_up_cycles = 8; // the PRNG is delayed by 8 cycles due to the NAC (4Bits = 0x05 encrypted) transfer
2021
2022 if (nt_diff == 0)
2023 {
2024 par_low = par & 0x07; // there is no need to check all parities for other nt_diff. Parity Bits for mf_nr_ar[0..2] won't change
2025 }
2026
2027 led_on = !led_on;
2028 if(led_on) LED_B_ON(); else LED_B_OFF();
2029
2030 par_list[nt_diff] = par;
2031 ks_list[nt_diff] = receivedAnswer[0] ^ 0x05;
2032
2033 // Test if the information is complete
2034 if (nt_diff == 0x07) {
2035 isOK = 1;
2036 break;
2037 }
2038
2039 nt_diff = (nt_diff + 1) & 0x07;
2040 mf_nr_ar[3] = (mf_nr_ar[3] & 0x1F) | (nt_diff << 5);
2041 par = par_low;
2042 } else {
2043 if (nt_diff == 0 && first_try)
2044 {
2045 par++;
2046 } else {
2047 par = (((par >> 3) + 1) << 3) | par_low;
2048 }
2049 }
2050 }
2051
2052 LogTrace((const uint8_t *)&nt, 4, 0, GetParity((const uint8_t *)&nt, 4), TRUE);
2053 LogTrace(par_list, 8, 0, GetParity(par_list, 8), TRUE);
2054 LogTrace(ks_list, 8, 0, GetParity(ks_list, 8), TRUE);
2055
2056 mf_nr_ar[3] &= 0x1F;
2057
2058 byte_t buf[28];
2059 memcpy(buf + 0, uid, 4);
2060 num_to_bytes(nt, 4, buf + 4);
2061 memcpy(buf + 8, par_list, 8);
2062 memcpy(buf + 16, ks_list, 8);
2063 memcpy(buf + 24, mf_nr_ar, 4);
2064
2065 cmd_send(CMD_ACK,isOK,0,0,buf,28);
2066
2067 // Thats it...
2068 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
2069 LEDsoff();
2070 tracing = TRUE;
2071 }
2072
2073 //-----------------------------------------------------------------------------
2074 // MIFARE 1K simulate.
2075 //
2076 //-----------------------------------------------------------------------------
2077 void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain)
2078 {
2079 int cardSTATE = MFEMUL_NOFIELD;
2080 int _7BUID = 0;
2081 int vHf = 0; // in mV
2082 //int nextCycleTimeout = 0;
2083 int res;
2084 // uint32_t timer = 0;
2085 uint32_t selTimer = 0;
2086 uint32_t authTimer = 0;
2087 uint32_t par = 0;
2088 int len = 0;
2089 uint8_t cardWRBL = 0;
2090 uint8_t cardAUTHSC = 0;
2091 uint8_t cardAUTHKEY = 0xff; // no authentication
2092 //uint32_t cardRn = 0;
2093 uint32_t cardRr = 0;
2094 uint32_t cuid = 0;
2095 //uint32_t rn_enc = 0;
2096 uint32_t ans = 0;
2097 uint32_t cardINTREG = 0;
2098 uint8_t cardINTBLOCK = 0;
2099 struct Crypto1State mpcs = {0, 0};
2100 struct Crypto1State *pcs;
2101 pcs = &mpcs;
2102
2103 uint8_t* receivedCmd = eml_get_bigbufptr_recbuf();
2104 uint8_t *response = eml_get_bigbufptr_sendbuf();
2105
2106 static uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID
2107
2108 static uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62};
2109 static uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; // !!!
2110
2111 static uint8_t rSAK[] = {0x08, 0xb6, 0xdd};
2112 static uint8_t rSAK1[] = {0x04, 0xda, 0x17};
2113
2114 static uint8_t rAUTH_NT[] = {0x01, 0x02, 0x03, 0x04};
2115 // static uint8_t rAUTH_NT[] = {0x1a, 0xac, 0xff, 0x4f};
2116 static uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00};
2117
2118 // clear trace
2119 traceLen = 0;
2120 tracing = true;
2121
2122 // Authenticate response - nonce
2123 uint32_t nonce = bytes_to_num(rAUTH_NT, 4);
2124
2125 // get UID from emul memory
2126 emlGetMemBt(receivedCmd, 7, 1);
2127 _7BUID = !(receivedCmd[0] == 0x00);
2128 if (!_7BUID) { // ---------- 4BUID
2129 rATQA[0] = 0x04;
2130
2131 emlGetMemBt(rUIDBCC1, 0, 4);
2132 rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
2133 } else { // ---------- 7BUID
2134 rATQA[0] = 0x44;
2135
2136 rUIDBCC1[0] = 0x88;
2137 emlGetMemBt(&rUIDBCC1[1], 0, 3);
2138 rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
2139 emlGetMemBt(rUIDBCC2, 3, 4);
2140 rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3];
2141 }
2142
2143 // -------------------------------------- test area
2144
2145 // -------------------------------------- END test area
2146 // start mkseconds counter
2147 StartCountUS();
2148
2149 // We need to listen to the high-frequency, peak-detected path.
2150 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
2151 FpgaSetupSsc();
2152
2153 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
2154 SpinDelay(200);
2155
2156 if (MF_DBGLEVEL >= 1) Dbprintf("Started. 7buid=%d", _7BUID);
2157 // calibrate mkseconds counter
2158 GetDeltaCountUS();
2159 while (true) {
2160 WDT_HIT();
2161
2162 if(BUTTON_PRESS()) {
2163 break;
2164 }
2165
2166 // find reader field
2167 // Vref = 3300mV, and an 10:1 voltage divider on the input
2168 // can measure voltages up to 33000 mV
2169 if (cardSTATE == MFEMUL_NOFIELD) {
2170 vHf = (33000 * AvgAdc(ADC_CHAN_HF)) >> 10;
2171 if (vHf > MF_MINFIELDV) {
2172 cardSTATE_TO_IDLE();
2173 LED_A_ON();
2174 }
2175 }
2176
2177 if (cardSTATE != MFEMUL_NOFIELD) {
2178 res = EmGetCmd(receivedCmd, &len, RECV_CMD_SIZE); // (+ nextCycleTimeout)
2179 if (res == 2) {
2180 cardSTATE = MFEMUL_NOFIELD;
2181 LEDsoff();
2182 continue;
2183 }
2184 if(res) break;
2185 }
2186
2187 //nextCycleTimeout = 0;
2188
2189 // if (len) Dbprintf("len:%d cmd: %02x %02x %02x %02x", len, receivedCmd[0], receivedCmd[1], receivedCmd[2], receivedCmd[3]);
2190
2191 if (len != 4 && cardSTATE != MFEMUL_NOFIELD) { // len != 4 <---- speed up the code 4 authentication
2192 // REQ or WUP request in ANY state and WUP in HALTED state
2193 if (len == 1 && ((receivedCmd[0] == 0x26 && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == 0x52)) {
2194 selTimer = GetTickCount();
2195 EmSendCmdEx(rATQA, sizeof(rATQA), (receivedCmd[0] == 0x52));
2196 cardSTATE = MFEMUL_SELECT1;
2197
2198 // init crypto block
2199 LED_B_OFF();
2200 LED_C_OFF();
2201 crypto1_destroy(pcs);
2202 cardAUTHKEY = 0xff;
2203 }
2204 }
2205
2206 switch (cardSTATE) {
2207 case MFEMUL_NOFIELD:{
2208 break;
2209 }
2210 case MFEMUL_HALTED:{
2211 break;
2212 }
2213 case MFEMUL_IDLE:{
2214 break;
2215 }
2216 case MFEMUL_SELECT1:{
2217 // select all
2218 if (len == 2 && (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x20)) {
2219 EmSendCmd(rUIDBCC1, sizeof(rUIDBCC1));
2220 break;
2221 }
2222
2223 // select card
2224 if (len == 9 &&
2225 (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC1, 4) == 0)) {
2226 if (!_7BUID)
2227 EmSendCmd(rSAK, sizeof(rSAK));
2228 else
2229 EmSendCmd(rSAK1, sizeof(rSAK1));
2230
2231 cuid = bytes_to_num(rUIDBCC1, 4);
2232 if (!_7BUID) {
2233 cardSTATE = MFEMUL_WORK;
2234 LED_B_ON();
2235 if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol1 time: %d", GetTickCount() - selTimer);
2236 break;
2237 } else {
2238 cardSTATE = MFEMUL_SELECT2;
2239 break;
2240 }
2241 }
2242
2243 break;
2244 }
2245 case MFEMUL_SELECT2:{
2246 if (!len) break;
2247
2248 if (len == 2 && (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x20)) {
2249 EmSendCmd(rUIDBCC2, sizeof(rUIDBCC2));
2250 break;
2251 }
2252
2253 // select 2 card
2254 if (len == 9 &&
2255 (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC2, 4) == 0)) {
2256 EmSendCmd(rSAK, sizeof(rSAK));
2257
2258 cuid = bytes_to_num(rUIDBCC2, 4);
2259 cardSTATE = MFEMUL_WORK;
2260 LED_B_ON();
2261 if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol2 time: %d", GetTickCount() - selTimer);
2262 break;
2263 }
2264
2265 // i guess there is a command). go into the work state.
2266 if (len != 4) break;
2267 cardSTATE = MFEMUL_WORK;
2268 goto lbWORK;
2269 }
2270 case MFEMUL_AUTH1:{
2271 if (len == 8) {
2272 // --- crypto
2273 //rn_enc = bytes_to_num(receivedCmd, 4);
2274 //cardRn = rn_enc ^ crypto1_word(pcs, rn_enc , 1);
2275 cardRr = bytes_to_num(&receivedCmd[4], 4) ^ crypto1_word(pcs, 0, 0);
2276 // test if auth OK
2277 if (cardRr != prng_successor(nonce, 64)){
2278 if (MF_DBGLEVEL >= 4) Dbprintf("AUTH FAILED. cardRr=%08x, succ=%08x", cardRr, prng_successor(nonce, 64));
2279 cardSTATE_TO_IDLE();
2280 break;
2281 }
2282 ans = prng_successor(nonce, 96) ^ crypto1_word(pcs, 0, 0);
2283 num_to_bytes(ans, 4, rAUTH_AT);
2284 // --- crypto
2285 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
2286 cardSTATE = MFEMUL_AUTH2;
2287 } else {
2288 cardSTATE_TO_IDLE();
2289 }
2290 if (cardSTATE != MFEMUL_AUTH2) break;
2291 }
2292 case MFEMUL_AUTH2:{
2293 LED_C_ON();
2294 cardSTATE = MFEMUL_WORK;
2295 if (MF_DBGLEVEL >= 4) Dbprintf("AUTH COMPLETED. sec=%d, key=%d time=%d", cardAUTHSC, cardAUTHKEY, GetTickCount() - authTimer);
2296 break;
2297 }
2298 case MFEMUL_WORK:{
2299 lbWORK: if (len == 0) break;
2300
2301 if (cardAUTHKEY == 0xff) {
2302 // first authentication
2303 if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) {
2304 authTimer = GetTickCount();
2305
2306 cardAUTHSC = receivedCmd[1] / 4; // received block num
2307 cardAUTHKEY = receivedCmd[0] - 0x60;
2308
2309 // --- crypto
2310 crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
2311 ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0);
2312 num_to_bytes(nonce, 4, rAUTH_AT);
2313 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
2314 // --- crypto
2315
2316 // last working revision
2317 // EmSendCmd14443aRaw(resp1, resp1Len, 0);
2318 // LogTrace(NULL, 0, GetDeltaCountUS(), 0, true);
2319
2320 cardSTATE = MFEMUL_AUTH1;
2321 //nextCycleTimeout = 10;
2322 break;
2323 }
2324 } else {
2325 // decrypt seqence
2326 mf_crypto1_decrypt(pcs, receivedCmd, len);
2327
2328 // nested authentication
2329 if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) {
2330 authTimer = GetTickCount();
2331
2332 cardAUTHSC = receivedCmd[1] / 4; // received block num
2333 cardAUTHKEY = receivedCmd[0] - 0x60;
2334
2335 // --- crypto
2336 crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
2337 ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0);
2338 num_to_bytes(ans, 4, rAUTH_AT);
2339 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
2340 // --- crypto
2341
2342 cardSTATE = MFEMUL_AUTH1;
2343 //nextCycleTimeout = 10;
2344 break;
2345 }
2346 }
2347
2348 // rule 13 of 7.5.3. in ISO 14443-4. chaining shall be continued
2349 // BUT... ACK --> NACK
2350 if (len == 1 && receivedCmd[0] == CARD_ACK) {
2351 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2352 break;
2353 }
2354
2355 // rule 12 of 7.5.3. in ISO 14443-4. R(NAK) --> R(ACK)
2356 if (len == 1 && receivedCmd[0] == CARD_NACK_NA) {
2357 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2358 break;
2359 }
2360
2361 // read block
2362 if (len == 4 && receivedCmd[0] == 0x30) {
2363 if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
2364 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2365 break;
2366 }
2367 emlGetMem(response, receivedCmd[1], 1);
2368 AppendCrc14443a(response, 16);
2369 mf_crypto1_encrypt(pcs, response, 18, &par);
2370 EmSendCmdPar(response, 18, par);
2371 break;
2372 }
2373
2374 // write block
2375 if (len == 4 && receivedCmd[0] == 0xA0) {
2376 if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
2377 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2378 break;
2379 }
2380 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2381 //nextCycleTimeout = 50;
2382 cardSTATE = MFEMUL_WRITEBL2;
2383 cardWRBL = receivedCmd[1];
2384 break;
2385 }
2386
2387 // works with cardINTREG
2388
2389 // increment, decrement, restore
2390 if (len == 4 && (receivedCmd[0] == 0xC0 || receivedCmd[0] == 0xC1 || receivedCmd[0] == 0xC2)) {
2391 if (receivedCmd[1] >= 16 * 4 ||
2392 receivedCmd[1] / 4 != cardAUTHSC ||
2393 emlCheckValBl(receivedCmd[1])) {
2394 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2395 break;
2396 }
2397 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2398 if (receivedCmd[0] == 0xC1)
2399 cardSTATE = MFEMUL_INTREG_INC;
2400 if (receivedCmd[0] == 0xC0)
2401 cardSTATE = MFEMUL_INTREG_DEC;
2402 if (receivedCmd[0] == 0xC2)
2403 cardSTATE = MFEMUL_INTREG_REST;
2404 cardWRBL = receivedCmd[1];
2405
2406 break;
2407 }
2408
2409
2410 // transfer
2411 if (len == 4 && receivedCmd[0] == 0xB0) {
2412 if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
2413 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2414 break;
2415 }
2416
2417 if (emlSetValBl(cardINTREG, cardINTBLOCK, receivedCmd[1]))
2418 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2419 else
2420 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2421
2422 break;
2423 }
2424
2425 // halt
2426 if (len == 4 && (receivedCmd[0] == 0x50 && receivedCmd[1] == 0x00)) {
2427 LED_B_OFF();
2428 LED_C_OFF();
2429 cardSTATE = MFEMUL_HALTED;
2430 if (MF_DBGLEVEL >= 4) Dbprintf("--> HALTED. Selected time: %d ms", GetTickCount() - selTimer);
2431 break;
2432 }
2433
2434 // command not allowed
2435 if (len == 4) {
2436 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2437 break;
2438 }
2439
2440 // case break
2441 break;
2442 }
2443 case MFEMUL_WRITEBL2:{
2444 if (len == 18){
2445 mf_crypto1_decrypt(pcs, receivedCmd, len);
2446 emlSetMem(receivedCmd, cardWRBL, 1);
2447 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2448 cardSTATE = MFEMUL_WORK;
2449 break;
2450 } else {
2451 cardSTATE_TO_IDLE();
2452 break;
2453 }
2454 break;
2455 }
2456
2457 case MFEMUL_INTREG_INC:{
2458 mf_crypto1_decrypt(pcs, receivedCmd, len);
2459 memcpy(&ans, receivedCmd, 4);
2460 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
2461 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2462 cardSTATE_TO_IDLE();
2463 break;
2464 }
2465 cardINTREG = cardINTREG + ans;
2466 cardSTATE = MFEMUL_WORK;
2467 break;
2468 }
2469 case MFEMUL_INTREG_DEC:{
2470 mf_crypto1_decrypt(pcs, receivedCmd, len);
2471 memcpy(&ans, receivedCmd, 4);
2472 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
2473 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2474 cardSTATE_TO_IDLE();
2475 break;
2476 }
2477 cardINTREG = cardINTREG - ans;
2478 cardSTATE = MFEMUL_WORK;
2479 break;
2480 }
2481 case MFEMUL_INTREG_REST:{
2482 mf_crypto1_decrypt(pcs, receivedCmd, len);
2483 memcpy(&ans, receivedCmd, 4);
2484 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
2485 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2486 cardSTATE_TO_IDLE();
2487 break;
2488 }
2489 cardSTATE = MFEMUL_WORK;
2490 break;
2491 }
2492 }
2493 }
2494
2495 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
2496 LEDsoff();
2497
2498 // add trace trailer
2499 memset(rAUTH_NT, 0x44, 4);
2500 LogTrace(rAUTH_NT, 4, 0, 0, TRUE);
2501
2502 if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, traceLen);
2503 }
2504
2505 //-----------------------------------------------------------------------------
2506 // MIFARE sniffer.
2507 //
2508 //-----------------------------------------------------------------------------
2509 void RAMFUNC SniffMifare(uint8_t param) {
2510 // param:
2511 // bit 0 - trigger from first card answer
2512 // bit 1 - trigger from first reader 7-bit request
2513
2514 // C(red) A(yellow) B(green)
2515 LEDsoff();
2516 // init trace buffer
2517 iso14a_clear_trace();
2518
2519 // The command (reader -> tag) that we're receiving.
2520 // The length of a received command will in most cases be no more than 18 bytes.
2521 // So 32 should be enough!
2522 uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
2523 // The response (tag -> reader) that we're receiving.
2524 uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET);
2525
2526 // As we receive stuff, we copy it from receivedCmd or receivedResponse
2527 // into trace, along with its length and other annotations.
2528 //uint8_t *trace = (uint8_t *)BigBuf;
2529
2530 // The DMA buffer, used to stream samples from the FPGA
2531 int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET;
2532 int8_t *data = dmaBuf;
2533 int maxDataLen = 0;
2534 int dataLen = 0;
2535
2536 // Set up the demodulator for tag -> reader responses.
2537 Demod.output = receivedResponse;
2538 Demod.len = 0;
2539 Demod.state = DEMOD_UNSYNCD;
2540
2541 // Set up the demodulator for the reader -> tag commands
2542 memset(&Uart, 0, sizeof(Uart));
2543 Uart.output = receivedCmd;
2544 Uart.byteCntMax = 32; // was 100 (greg)//////////////////
2545 Uart.state = STATE_UNSYNCD;
2546
2547 // Setup for the DMA.
2548 FpgaSetupSsc();
2549 FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
2550
2551 // And put the FPGA in the appropriate mode
2552 // Signal field is off with the appropriate LED
2553 LED_D_OFF();
2554 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER);
2555 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
2556
2557 // init sniffer
2558 MfSniffInit();
2559 int sniffCounter = 0;
2560
2561 // And now we loop, receiving samples.
2562 while(true) {
2563 if(BUTTON_PRESS()) {
2564 DbpString("cancelled by button");
2565 goto done;
2566 }
2567
2568 LED_A_ON();
2569 WDT_HIT();
2570
2571 if (++sniffCounter > 65) {
2572 if (MfSniffSend(2000)) {
2573 FpgaEnableSscDma();
2574 }
2575 sniffCounter = 0;
2576 }
2577
2578 int register readBufDataP = data - dmaBuf;
2579 int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR;
2580 if (readBufDataP <= dmaBufDataP){
2581 dataLen = dmaBufDataP - readBufDataP;
2582 } else {
2583 dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP + 1;
2584 }
2585 // test for length of buffer
2586 if(dataLen > maxDataLen) {
2587 maxDataLen = dataLen;
2588 if(dataLen > 400) {
2589 Dbprintf("blew circular buffer! dataLen=0x%x", dataLen);
2590 goto done;
2591 }
2592 }
2593 if(dataLen < 1) continue;
2594
2595 // primary buffer was stopped( <-- we lost data!
2596 if (!AT91C_BASE_PDC_SSC->PDC_RCR) {
2597 AT91C_BASE_PDC_SSC->PDC_RPR = (uint32_t) dmaBuf;
2598 AT91C_BASE_PDC_SSC->PDC_RCR = DMA_BUFFER_SIZE;
2599 Dbprintf("RxEmpty ERROR!!! data length:%d", dataLen); // temporary
2600 }
2601 // secondary buffer sets as primary, secondary buffer was stopped
2602 if (!AT91C_BASE_PDC_SSC->PDC_RNCR) {
2603 AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf;
2604 AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
2605 }
2606
2607 LED_A_OFF();
2608
2609 if(MillerDecoding((data[0] & 0xF0) >> 4)) {
2610 LED_C_INV();
2611 // check - if there is a short 7bit request from reader
2612 if (MfSniffLogic(receivedCmd, Uart.byteCnt, Uart.parityBits, Uart.bitCnt, TRUE)) break;
2613
2614 /* And ready to receive another command. */
2615 Uart.state = STATE_UNSYNCD;
2616
2617 /* And also reset the demod code */
2618 Demod.state = DEMOD_UNSYNCD;
2619 }
2620
2621 if(ManchesterDecoding(data[0] & 0x0F)) {
2622 LED_C_INV();
2623
2624 if (MfSniffLogic(receivedResponse, Demod.len, Demod.parityBits, Demod.bitCount, FALSE)) break;
2625
2626 // And ready to receive another response.
2627 memset(&Demod, 0, sizeof(Demod));
2628 Demod.output = receivedResponse;
2629 Demod.state = DEMOD_UNSYNCD;
2630
2631 /* And also reset the uart code */
2632 Uart.state = STATE_UNSYNCD;
2633 }
2634
2635 data++;
2636 if(data > dmaBuf + DMA_BUFFER_SIZE) {
2637 data = dmaBuf;
2638 }
2639 } // main cycle
2640
2641 DbpString("COMMAND FINISHED");
2642
2643 done:
2644 FpgaDisableSscDma();
2645 MfSniffEnd();
2646
2647 Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.byteCnt=%x Uart.byteCntMax=%x", maxDataLen, Uart.state, Uart.byteCnt, Uart.byteCntMax);
2648 LEDsoff();
2649 }
Proxmark3 GIT tracking
Impressum, Datenschutz