]> git.zerfleddert.de Git - proxmark3-svn/blob - armsrc/iso14443a.c
Minor fix, sometimes when data is sent without the pm3 is connected, it causes a...
[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 static uint8_t* free_buffer_pointer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);
912
913 typedef struct {
914 uint8_t* response;
915 size_t response_n;
916 uint8_t* modulation;
917 size_t modulation_n;
918 } tag_response_info_t;
919
920 void reset_free_buffer() {
921 free_buffer_pointer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);
922 }
923
924 bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffer_size) {
925 // Exmaple response, answer to MIFARE Classic read block will be 16 bytes + 2 CRC = 18 bytes
926 // This will need the following byte array for a modulation sequence
927 // 144 data bits (18 * 8)
928 // 18 parity bits
929 // 2 Start and stop
930 // 1 Correction bit (Answer in 1172 or 1236 periods, see FPGA)
931 // 1 just for the case
932 // ----------- +
933 // 166 bytes, since every bit that needs to be send costs us a byte
934 //
935
936 // Prepare the tag modulation bits from the message
937 CodeIso14443aAsTag(response_info->response,response_info->response_n);
938
939 // Make sure we do not exceed the free buffer space
940 if (ToSendMax > max_buffer_size) {
941 Dbprintf("Out of memory, when modulating bits for tag answer:");
942 Dbhexdump(response_info->response_n,response_info->response,false);
943 return false;
944 }
945
946 // Copy the byte array, used for this modulation to the buffer position
947 memcpy(response_info->modulation,ToSend,ToSendMax);
948
949 // Store the number of bytes that were used for encoding/modulation
950 response_info->modulation_n = ToSendMax;
951
952 return true;
953 }
954
955 bool prepare_allocated_tag_modulation(tag_response_info_t* response_info) {
956 // Retrieve and store the current buffer index
957 response_info->modulation = free_buffer_pointer;
958
959 // Determine the maximum size we can use from our buffer
960 size_t max_buffer_size = (((uint8_t *)BigBuf)+FREE_BUFFER_OFFSET+FREE_BUFFER_SIZE)-free_buffer_pointer;
961
962 // Forward the prepare tag modulation function to the inner function
963 if (prepare_tag_modulation(response_info,max_buffer_size)) {
964 // Update the free buffer offset
965 free_buffer_pointer += ToSendMax;
966 return true;
967 } else {
968 return false;
969 }
970 }
971
972 //-----------------------------------------------------------------------------
973 // Main loop of simulated tag: receive commands from reader, decide what
974 // response to send, and send it.
975 //-----------------------------------------------------------------------------
976 void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
977 {
978 // Enable and clear the trace
979 tracing = TRUE;
980 iso14a_clear_trace();
981
982 // This function contains the tag emulation
983 uint8_t sak;
984
985 // The first response contains the ATQA (note: bytes are transmitted in reverse order).
986 uint8_t response1[2];
987
988 switch (tagType) {
989 case 1: { // MIFARE Classic
990 // Says: I am Mifare 1k - original line
991 response1[0] = 0x04;
992 response1[1] = 0x00;
993 sak = 0x08;
994 } break;
995 case 2: { // MIFARE Ultralight
996 // Says: I am a stupid memory tag, no crypto
997 response1[0] = 0x04;
998 response1[1] = 0x00;
999 sak = 0x00;
1000 } break;
1001 case 3: { // MIFARE DESFire
1002 // Says: I am a DESFire tag, ph33r me
1003 response1[0] = 0x04;
1004 response1[1] = 0x03;
1005 sak = 0x20;
1006 } break;
1007 case 4: { // ISO/IEC 14443-4
1008 // Says: I am a javacard (JCOP)
1009 response1[0] = 0x04;
1010 response1[1] = 0x00;
1011 sak = 0x28;
1012 } break;
1013 default: {
1014 Dbprintf("Error: unkown tagtype (%d)",tagType);
1015 return;
1016 } break;
1017 }
1018
1019 // The second response contains the (mandatory) first 24 bits of the UID
1020 uint8_t response2[5];
1021
1022 // Check if the uid uses the (optional) part
1023 uint8_t response2a[5];
1024 if (uid_2nd) {
1025 response2[0] = 0x88;
1026 num_to_bytes(uid_1st,3,response2+1);
1027 num_to_bytes(uid_2nd,4,response2a);
1028 response2a[4] = response2a[0] ^ response2a[1] ^ response2a[2] ^ response2a[3];
1029
1030 // Configure the ATQA and SAK accordingly
1031 response1[0] |= 0x40;
1032 sak |= 0x04;
1033 } else {
1034 num_to_bytes(uid_1st,4,response2);
1035 // Configure the ATQA and SAK accordingly
1036 response1[0] &= 0xBF;
1037 sak &= 0xFB;
1038 }
1039
1040 // Calculate the BitCountCheck (BCC) for the first 4 bytes of the UID.
1041 response2[4] = response2[0] ^ response2[1] ^ response2[2] ^ response2[3];
1042
1043 // Prepare the mandatory SAK (for 4 and 7 byte UID)
1044 uint8_t response3[3];
1045 response3[0] = sak;
1046 ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]);
1047
1048 // Prepare the optional second SAK (for 7 byte UID), drop the cascade bit
1049 uint8_t response3a[3];
1050 response3a[0] = sak & 0xFB;
1051 ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);
1052
1053 uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce
1054 uint8_t response6[] = { 0x04, 0x58, 0x00, 0x02, 0x00, 0x00 }; // dummy ATS (pseudo-ATR), answer to RATS
1055 ComputeCrc14443(CRC_14443_A, response6, 4, &response6[4], &response6[5]);
1056
1057 #define TAG_RESPONSE_COUNT 7
1058 tag_response_info_t responses[TAG_RESPONSE_COUNT] = {
1059 { .response = response1, .response_n = sizeof(response1) }, // Answer to request - respond with card type
1060 { .response = response2, .response_n = sizeof(response2) }, // Anticollision cascade1 - respond with uid
1061 { .response = response2a, .response_n = sizeof(response2a) }, // Anticollision cascade2 - respond with 2nd half of uid if asked
1062 { .response = response3, .response_n = sizeof(response3) }, // Acknowledge select - cascade 1
1063 { .response = response3a, .response_n = sizeof(response3a) }, // Acknowledge select - cascade 2
1064 { .response = response5, .response_n = sizeof(response5) }, // Authentication answer (random nonce)
1065 { .response = response6, .response_n = sizeof(response6) }, // dummy ATS (pseudo-ATR), answer to RATS
1066 };
1067
1068 // Allocate 512 bytes for the dynamic modulation, created when the reader querries for it
1069 // Such a response is less time critical, so we can prepare them on the fly
1070 #define DYNAMIC_RESPONSE_BUFFER_SIZE 64
1071 #define DYNAMIC_MODULATION_BUFFER_SIZE 512
1072 uint8_t dynamic_response_buffer[DYNAMIC_RESPONSE_BUFFER_SIZE];
1073 uint8_t dynamic_modulation_buffer[DYNAMIC_MODULATION_BUFFER_SIZE];
1074 tag_response_info_t dynamic_response_info = {
1075 .response = dynamic_response_buffer,
1076 .response_n = 0,
1077 .modulation = dynamic_modulation_buffer,
1078 .modulation_n = 0
1079 };
1080
1081 // Reset the offset pointer of the free buffer
1082 reset_free_buffer();
1083
1084 // Prepare the responses of the anticollision phase
1085 // there will be not enough time to do this at the moment the reader sends it REQA
1086 for (size_t i=0; i<TAG_RESPONSE_COUNT; i++) {
1087 prepare_allocated_tag_modulation(&responses[i]);
1088 }
1089
1090 uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
1091 int len;
1092
1093 // To control where we are in the protocol
1094 int order = 0;
1095 int lastorder;
1096
1097 // Just to allow some checks
1098 int happened = 0;
1099 int happened2 = 0;
1100 int cmdsRecvd = 0;
1101
1102 // We need to listen to the high-frequency, peak-detected path.
1103 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
1104 FpgaSetupSsc();
1105
1106 cmdsRecvd = 0;
1107 tag_response_info_t* p_response;
1108
1109 LED_A_ON();
1110 for(;;) {
1111 // Clean receive command buffer
1112 memset(receivedCmd, 0x44, RECV_CMD_SIZE);
1113
1114 if(!GetIso14443aCommandFromReader(receivedCmd, &len, RECV_CMD_SIZE)) {
1115 DbpString("Button press");
1116 break;
1117 }
1118
1119 if (tracing) {
1120 LogTrace(receivedCmd,len, 0, Uart.parityBits, TRUE);
1121 }
1122
1123 p_response = NULL;
1124
1125 // 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
1126 // Okay, look at the command now.
1127 lastorder = order;
1128 if(receivedCmd[0] == 0x26) { // Received a REQUEST
1129 p_response = &responses[0]; order = 1;
1130 } else if(receivedCmd[0] == 0x52) { // Received a WAKEUP
1131 p_response = &responses[0]; order = 6;
1132 } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x93) { // Received request for UID (cascade 1)
1133 p_response = &responses[1]; order = 2;
1134 } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x95) { // Received request for UID (cascade 2)
1135 p_response = &responses[2]; order = 20;
1136 } else if(receivedCmd[1] == 0x70 && receivedCmd[0] == 0x93) { // Received a SELECT (cascade 1)
1137 p_response = &responses[3]; order = 3;
1138 } else if(receivedCmd[1] == 0x70 && receivedCmd[0] == 0x95) { // Received a SELECT (cascade 2)
1139 p_response = &responses[4]; order = 30;
1140 } else if(receivedCmd[0] == 0x30) { // Received a (plain) READ
1141 EmSendCmdEx(data+(4*receivedCmd[0]),16,false);
1142 Dbprintf("Read request from reader: %x %x",receivedCmd[0],receivedCmd[1]);
1143 // We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
1144 p_response = NULL;
1145 } else if(receivedCmd[0] == 0x50) { // Received a HALT
1146 // DbpString("Reader requested we HALT!:");
1147 p_response = NULL;
1148 } else if(receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61) { // Received an authentication request
1149 p_response = &responses[5]; order = 7;
1150 } else if(receivedCmd[0] == 0xE0) { // Received a RATS request
1151 p_response = &responses[6]; order = 70;
1152 } else if (order == 7 && len ==8) { // Received authentication request
1153 uint32_t nr = bytes_to_num(receivedCmd,4);
1154 uint32_t ar = bytes_to_num(receivedCmd+4,4);
1155 Dbprintf("Auth attempt {nr}{ar}: %08x %08x",nr,ar);
1156 } else {
1157 // Check for ISO 14443A-4 compliant commands, look at left nibble
1158 switch (receivedCmd[0]) {
1159
1160 case 0x0B:
1161 case 0x0A: { // IBlock (command)
1162 dynamic_response_info.response[0] = receivedCmd[0];
1163 dynamic_response_info.response[1] = 0x00;
1164 dynamic_response_info.response[2] = 0x90;
1165 dynamic_response_info.response[3] = 0x00;
1166 dynamic_response_info.response_n = 4;
1167 } break;
1168
1169 case 0x1A:
1170 case 0x1B: { // Chaining command
1171 dynamic_response_info.response[0] = 0xaa | ((receivedCmd[0]) & 1);
1172 dynamic_response_info.response_n = 2;
1173 } break;
1174
1175 case 0xaa:
1176 case 0xbb: {
1177 dynamic_response_info.response[0] = receivedCmd[0] ^ 0x11;
1178 dynamic_response_info.response_n = 2;
1179 } break;
1180
1181 case 0xBA: { //
1182 memcpy(dynamic_response_info.response,"\xAB\x00",2);
1183 dynamic_response_info.response_n = 2;
1184 } break;
1185
1186 case 0xCA:
1187 case 0xC2: { // Readers sends deselect command
1188 memcpy(dynamic_response_info.response,"\xCA\x00",2);
1189 dynamic_response_info.response_n = 2;
1190 } break;
1191
1192 default: {
1193 // Never seen this command before
1194 Dbprintf("Received unknown command (len=%d):",len);
1195 Dbhexdump(len,receivedCmd,false);
1196 // Do not respond
1197 dynamic_response_info.response_n = 0;
1198 } break;
1199 }
1200
1201 if (dynamic_response_info.response_n > 0) {
1202 // Copy the CID from the reader query
1203 dynamic_response_info.response[1] = receivedCmd[1];
1204
1205 // Add CRC bytes, always used in ISO 14443A-4 compliant cards
1206 AppendCrc14443a(dynamic_response_info.response,dynamic_response_info.response_n);
1207 dynamic_response_info.response_n += 2;
1208
1209 if (prepare_tag_modulation(&dynamic_response_info,DYNAMIC_MODULATION_BUFFER_SIZE) == false) {
1210 Dbprintf("Error preparing tag response");
1211 break;
1212 }
1213 p_response = &dynamic_response_info;
1214 }
1215 }
1216
1217 // Count number of wakeups received after a halt
1218 if(order == 6 && lastorder == 5) { happened++; }
1219
1220 // Count number of other messages after a halt
1221 if(order != 6 && lastorder == 5) { happened2++; }
1222
1223 // Look at last parity bit to determine timing of answer
1224 if((Uart.parityBits & 0x01) || receivedCmd[0] == 0x52) {
1225 // 1236, so correction bit needed
1226 //i = 0;
1227 }
1228
1229 if(cmdsRecvd > 999) {
1230 DbpString("1000 commands later...");
1231 break;
1232 }
1233 cmdsRecvd++;
1234
1235 if (p_response != NULL) {
1236 EmSendCmd14443aRaw(p_response->modulation, p_response->modulation_n, receivedCmd[0] == 0x52);
1237 if (tracing) {
1238 LogTrace(p_response->response,p_response->response_n,0,SwapBits(GetParity(p_response->response,p_response->response_n),p_response->response_n),FALSE);
1239 if(traceLen > TRACE_SIZE) {
1240 DbpString("Trace full");
1241 // break;
1242 }
1243 }
1244 }
1245 }
1246
1247 Dbprintf("%x %x %x", happened, happened2, cmdsRecvd);
1248 LED_A_OFF();
1249 }
1250
1251
1252 // prepare a delayed transfer. This simply shifts ToSend[] by a number
1253 // of bits specified in the delay parameter.
1254 void PrepareDelayedTransfer(uint16_t delay)
1255 {
1256 uint8_t bitmask = 0;
1257 uint8_t bits_to_shift = 0;
1258 uint8_t bits_shifted = 0;
1259
1260 delay &= 0x07;
1261 if (delay) {
1262 for (uint16_t i = 0; i < delay; i++) {
1263 bitmask |= (0x01 << i);
1264 }
1265 ToSend[++ToSendMax] = 0x00;
1266 for (uint16_t i = 0; i < ToSendMax; i++) {
1267 bits_to_shift = ToSend[i] & bitmask;
1268 ToSend[i] = ToSend[i] >> delay;
1269 ToSend[i] = ToSend[i] | (bits_shifted << (8 - delay));
1270 bits_shifted = bits_to_shift;
1271 }
1272 }
1273 }
1274
1275 //-----------------------------------------------------------------------------
1276 // Transmit the command (to the tag) that was placed in ToSend[].
1277 // Parameter timing:
1278 // if NULL: ignored
1279 // if == 0: return time of transfer
1280 // if != 0: delay transfer until time specified
1281 //-----------------------------------------------------------------------------
1282 static void TransmitFor14443a(const uint8_t *cmd, int len, uint32_t *timing)
1283 {
1284 int c;
1285
1286 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1287
1288
1289 if (timing) {
1290 if(*timing == 0) { // Measure time
1291 *timing = (GetCountMifare() + 8) & 0xfffffff8;
1292 } else {
1293 PrepareDelayedTransfer(*timing & 0x00000007); // Delay transfer (fine tuning - up to 7 MF clock ticks)
1294 }
1295 if(MF_DBGLEVEL >= 4 && GetCountMifare() >= (*timing & 0xfffffff8)) Dbprintf("TransmitFor14443a: Missed timing");
1296 while(GetCountMifare() < (*timing & 0xfffffff8)); // Delay transfer (multiple of 8 MF clock ticks)
1297 }
1298
1299 for(c = 0; c < 10;) { // standard delay for each transfer (allow tag to be ready after last transmission)
1300 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1301 AT91C_BASE_SSC->SSC_THR = 0x00;
1302 c++;
1303 }
1304 }
1305
1306 c = 0;
1307 for(;;) {
1308 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1309 AT91C_BASE_SSC->SSC_THR = cmd[c];
1310 c++;
1311 if(c >= len) {
1312 break;
1313 }
1314 }
1315 }
1316
1317 }
1318
1319 //-----------------------------------------------------------------------------
1320 // Prepare reader command (in bits, support short frames) to send to FPGA
1321 //-----------------------------------------------------------------------------
1322 void CodeIso14443aBitsAsReaderPar(const uint8_t * cmd, int bits, uint32_t dwParity)
1323 {
1324 int i, j;
1325 int last;
1326 uint8_t b;
1327
1328 ToSendReset();
1329
1330 // Start of Communication (Seq. Z)
1331 ToSend[++ToSendMax] = SEC_Z;
1332 last = 0;
1333
1334 size_t bytecount = nbytes(bits);
1335 // Generate send structure for the data bits
1336 for (i = 0; i < bytecount; i++) {
1337 // Get the current byte to send
1338 b = cmd[i];
1339 size_t bitsleft = MIN((bits-(i*8)),8);
1340
1341 for (j = 0; j < bitsleft; j++) {
1342 if (b & 1) {
1343 // Sequence X
1344 ToSend[++ToSendMax] = SEC_X;
1345 last = 1;
1346 } else {
1347 if (last == 0) {
1348 // Sequence Z
1349 ToSend[++ToSendMax] = SEC_Z;
1350 } else {
1351 // Sequence Y
1352 ToSend[++ToSendMax] = SEC_Y;
1353 last = 0;
1354 }
1355 }
1356 b >>= 1;
1357 }
1358
1359 // Only transmit (last) parity bit if we transmitted a complete byte
1360 if (j == 8) {
1361 // Get the parity bit
1362 if ((dwParity >> i) & 0x01) {
1363 // Sequence X
1364 ToSend[++ToSendMax] = SEC_X;
1365 last = 1;
1366 } else {
1367 if (last == 0) {
1368 // Sequence Z
1369 ToSend[++ToSendMax] = SEC_Z;
1370 } else {
1371 // Sequence Y
1372 ToSend[++ToSendMax] = SEC_Y;
1373 last = 0;
1374 }
1375 }
1376 }
1377 }
1378
1379 // End of Communication
1380 if (last == 0) {
1381 // Sequence Z
1382 ToSend[++ToSendMax] = SEC_Z;
1383 } else {
1384 // Sequence Y
1385 ToSend[++ToSendMax] = SEC_Y;
1386 last = 0;
1387 }
1388 // Sequence Y
1389 ToSend[++ToSendMax] = SEC_Y;
1390
1391 // Just to be sure!
1392 ToSend[++ToSendMax] = SEC_Y;
1393 ToSend[++ToSendMax] = SEC_Y;
1394 ToSend[++ToSendMax] = SEC_Y;
1395
1396 // Convert from last character reference to length
1397 ToSendMax++;
1398 }
1399
1400 //-----------------------------------------------------------------------------
1401 // Prepare reader command to send to FPGA
1402 //-----------------------------------------------------------------------------
1403 void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
1404 {
1405 CodeIso14443aBitsAsReaderPar(cmd,len*8,dwParity);
1406 }
1407
1408 //-----------------------------------------------------------------------------
1409 // Wait for commands from reader
1410 // Stop when button is pressed (return 1) or field was gone (return 2)
1411 // Or return 0 when command is captured
1412 //-----------------------------------------------------------------------------
1413 static int EmGetCmd(uint8_t *received, int *len, int maxLen)
1414 {
1415 *len = 0;
1416
1417 uint32_t timer = 0, vtime = 0;
1418 int analogCnt = 0;
1419 int analogAVG = 0;
1420
1421 // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
1422 // only, since we are receiving, not transmitting).
1423 // Signal field is off with the appropriate LED
1424 LED_D_OFF();
1425 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
1426
1427 // Set ADC to read field strength
1428 AT91C_BASE_ADC->ADC_CR = AT91C_ADC_SWRST;
1429 AT91C_BASE_ADC->ADC_MR =
1430 ADC_MODE_PRESCALE(32) |
1431 ADC_MODE_STARTUP_TIME(16) |
1432 ADC_MODE_SAMPLE_HOLD_TIME(8);
1433 AT91C_BASE_ADC->ADC_CHER = ADC_CHANNEL(ADC_CHAN_HF);
1434 // start ADC
1435 AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
1436
1437 // Now run a 'software UART' on the stream of incoming samples.
1438 Uart.output = received;
1439 Uart.byteCntMax = maxLen;
1440 Uart.state = STATE_UNSYNCD;
1441
1442 for(;;) {
1443 WDT_HIT();
1444
1445 if (BUTTON_PRESS()) return 1;
1446
1447 // test if the field exists
1448 if (AT91C_BASE_ADC->ADC_SR & ADC_END_OF_CONVERSION(ADC_CHAN_HF)) {
1449 analogCnt++;
1450 analogAVG += AT91C_BASE_ADC->ADC_CDR[ADC_CHAN_HF];
1451 AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
1452 if (analogCnt >= 32) {
1453 if ((33000 * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) {
1454 vtime = GetTickCount();
1455 if (!timer) timer = vtime;
1456 // 50ms no field --> card to idle state
1457 if (vtime - timer > 50) return 2;
1458 } else
1459 if (timer) timer = 0;
1460 analogCnt = 0;
1461 analogAVG = 0;
1462 }
1463 }
1464 // transmit none
1465 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1466 AT91C_BASE_SSC->SSC_THR = 0x00;
1467 }
1468 // receive and test the miller decoding
1469 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1470 volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1471 if(MillerDecoding((b & 0xf0) >> 4)) {
1472 *len = Uart.byteCnt;
1473 if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE);
1474 return 0;
1475 }
1476 if(MillerDecoding(b & 0x0f)) {
1477 *len = Uart.byteCnt;
1478 if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE);
1479 return 0;
1480 }
1481 }
1482 }
1483 }
1484
1485 static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded)
1486 {
1487 int i, u = 0;
1488 uint8_t b = 0;
1489
1490 // Modulate Manchester
1491 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD);
1492 AT91C_BASE_SSC->SSC_THR = 0x00;
1493 FpgaSetupSsc();
1494
1495 // include correction bit
1496 i = 1;
1497 if((Uart.parityBits & 0x01) || correctionNeeded) {
1498 // 1236, so correction bit needed
1499 i = 0;
1500 }
1501
1502 // send cycle
1503 for(;;) {
1504 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1505 volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1506 (void)b;
1507 }
1508 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1509 if(i > respLen) {
1510 b = 0xff; // was 0x00
1511 u++;
1512 } else {
1513 b = resp[i];
1514 i++;
1515 }
1516 AT91C_BASE_SSC->SSC_THR = b;
1517
1518 if(u > 4) break;
1519 }
1520 if(BUTTON_PRESS()) {
1521 break;
1522 }
1523 }
1524
1525 return 0;
1526 }
1527
1528 int EmSend4bitEx(uint8_t resp, int correctionNeeded){
1529 Code4bitAnswerAsTag(resp);
1530 int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded);
1531 if (tracing) LogTrace(&resp, 1, GetDeltaCountUS(), GetParity(&resp, 1), FALSE);
1532 return res;
1533 }
1534
1535 int EmSend4bit(uint8_t resp){
1536 return EmSend4bitEx(resp, 0);
1537 }
1538
1539 int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par){
1540 CodeIso14443aAsTagPar(resp, respLen, par);
1541 int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded);
1542 if (tracing) LogTrace(resp, respLen, GetDeltaCountUS(), par, FALSE);
1543 return res;
1544 }
1545
1546 int EmSendCmdEx(uint8_t *resp, int respLen, int correctionNeeded){
1547 return EmSendCmdExPar(resp, respLen, correctionNeeded, GetParity(resp, respLen));
1548 }
1549
1550 int EmSendCmd(uint8_t *resp, int respLen){
1551 return EmSendCmdExPar(resp, respLen, 0, GetParity(resp, respLen));
1552 }
1553
1554 int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par){
1555 return EmSendCmdExPar(resp, respLen, 0, par);
1556 }
1557
1558 //-----------------------------------------------------------------------------
1559 // Wait a certain time for tag response
1560 // If a response is captured return TRUE
1561 // If it takes to long return FALSE
1562 //-----------------------------------------------------------------------------
1563 static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer
1564 {
1565 // buffer needs to be 512 bytes
1566 int c;
1567
1568 // Set FPGA mode to "reader listen mode", no modulation (listen
1569 // only, since we are receiving, not transmitting).
1570 // Signal field is on with the appropriate LED
1571 LED_D_ON();
1572 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);
1573
1574 // Now get the answer from the card
1575 Demod.output = receivedResponse;
1576 Demod.len = 0;
1577 Demod.state = DEMOD_UNSYNCD;
1578
1579 uint8_t b;
1580 if (elapsed) *elapsed = 0;
1581
1582 c = 0;
1583 for(;;) {
1584 WDT_HIT();
1585
1586 // if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
1587 // AT91C_BASE_SSC->SSC_THR = 0x00; // To make use of exact timing of next command from reader!!
1588 // if (elapsed) (*elapsed)++;
1589 // }
1590 if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
1591 if(c < iso14a_timeout) { c++; } else { return FALSE; }
1592 b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1593 if(ManchesterDecoding((b>>4) & 0xf)) {
1594 *samples = ((c - 1) << 3) + 4;
1595 return TRUE;
1596 }
1597 if(ManchesterDecoding(b & 0x0f)) {
1598 *samples = c << 3;
1599 return TRUE;
1600 }
1601 }
1602 }
1603 }
1604
1605 void ReaderTransmitBitsPar(uint8_t* frame, int bits, uint32_t par, uint32_t *timing)
1606 {
1607
1608 CodeIso14443aBitsAsReaderPar(frame,bits,par);
1609
1610 // Select the card
1611 TransmitFor14443a(ToSend, ToSendMax, timing);
1612 if(trigger)
1613 LED_A_ON();
1614
1615 // Store reader command in buffer
1616 if (tracing) LogTrace(frame,nbytes(bits),0,par,TRUE);
1617 }
1618
1619 void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par, uint32_t *timing)
1620 {
1621 ReaderTransmitBitsPar(frame,len*8,par, timing);
1622 }
1623
1624 void ReaderTransmit(uint8_t* frame, int len, uint32_t *timing)
1625 {
1626 // Generate parity and redirect
1627 ReaderTransmitBitsPar(frame,len*8,GetParity(frame,len), timing);
1628 }
1629
1630 int ReaderReceive(uint8_t* receivedAnswer)
1631 {
1632 int samples = 0;
1633 if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE;
1634 if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE);
1635 if(samples == 0) return FALSE;
1636 return Demod.len;
1637 }
1638
1639 int ReaderReceivePar(uint8_t* receivedAnswer, uint32_t * parptr)
1640 {
1641 int samples = 0;
1642 if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE;
1643 if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE);
1644 *parptr = Demod.parityBits;
1645 if(samples == 0) return FALSE;
1646 return Demod.len;
1647 }
1648
1649 /* performs iso14443a anticolision procedure
1650 * fills the uid pointer unless NULL
1651 * fills resp_data unless NULL */
1652 int iso14443a_select_card(byte_t* uid_ptr, iso14a_card_select_t* p_hi14a_card, uint32_t* cuid_ptr) {
1653 uint8_t wupa[] = { 0x52 }; // 0x26 - REQA 0x52 - WAKE-UP
1654 uint8_t sel_all[] = { 0x93,0x20 };
1655 uint8_t sel_uid[] = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
1656 uint8_t rats[] = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0
1657 uint8_t* resp = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); // was 3560 - tied to other size changes
1658 byte_t uid_resp[4];
1659 size_t uid_resp_len;
1660
1661 uint8_t sak = 0x04; // cascade uid
1662 int cascade_level = 0;
1663 int len;
1664
1665 // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
1666 ReaderTransmitBitsPar(wupa,7,0, NULL);
1667 // Receive the ATQA
1668 if(!ReaderReceive(resp)) return 0;
1669 // Dbprintf("atqa: %02x %02x",resp[0],resp[1]);
1670
1671 if(p_hi14a_card) {
1672 memcpy(p_hi14a_card->atqa, resp, 2);
1673 p_hi14a_card->uidlen = 0;
1674 memset(p_hi14a_card->uid,0,10);
1675 }
1676
1677 // clear uid
1678 if (uid_ptr) {
1679 memset(uid_ptr,0,10);
1680 }
1681
1682 // OK we will select at least at cascade 1, lets see if first byte of UID was 0x88 in
1683 // which case we need to make a cascade 2 request and select - this is a long UID
1684 // While the UID is not complete, the 3nd bit (from the right) is set in the SAK.
1685 for(; sak & 0x04; cascade_level++) {
1686 // SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97)
1687 sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2;
1688
1689 // SELECT_ALL
1690 ReaderTransmit(sel_all,sizeof(sel_all), NULL);
1691 if (!ReaderReceive(resp)) return 0;
1692
1693 // First backup the current uid
1694 memcpy(uid_resp,resp,4);
1695 uid_resp_len = 4;
1696 // Dbprintf("uid: %02x %02x %02x %02x",uid_resp[0],uid_resp[1],uid_resp[2],uid_resp[3]);
1697
1698 // calculate crypto UID. Always use last 4 Bytes.
1699 if(cuid_ptr) {
1700 *cuid_ptr = bytes_to_num(uid_resp, 4);
1701 }
1702
1703 // Construct SELECT UID command
1704 memcpy(sel_uid+2,resp,5);
1705 AppendCrc14443a(sel_uid,7);
1706 ReaderTransmit(sel_uid,sizeof(sel_uid), NULL);
1707
1708 // Receive the SAK
1709 if (!ReaderReceive(resp)) return 0;
1710 sak = resp[0];
1711
1712 // Test if more parts of the uid are comming
1713 if ((sak & 0x04) && uid_resp[0] == 0x88) {
1714 // Remove first byte, 0x88 is not an UID byte, it CT, see page 3 of:
1715 // http://www.nxp.com/documents/application_note/AN10927.pdf
1716 memcpy(uid_resp, uid_resp + 1, 3);
1717 uid_resp_len = 3;
1718 }
1719
1720 if(uid_ptr) {
1721 memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
1722 }
1723
1724 if(p_hi14a_card) {
1725 memcpy(p_hi14a_card->uid + (cascade_level*3), uid_resp, uid_resp_len);
1726 p_hi14a_card->uidlen += uid_resp_len;
1727 }
1728 }
1729
1730 if(p_hi14a_card) {
1731 p_hi14a_card->sak = sak;
1732 p_hi14a_card->ats_len = 0;
1733 }
1734
1735 if( (sak & 0x20) == 0) {
1736 return 2; // non iso14443a compliant tag
1737 }
1738
1739 // Request for answer to select
1740 AppendCrc14443a(rats, 2);
1741 ReaderTransmit(rats, sizeof(rats), NULL);
1742
1743 if (!(len = ReaderReceive(resp))) return 0;
1744
1745 if(p_hi14a_card) {
1746 memcpy(p_hi14a_card->ats, resp, sizeof(p_hi14a_card->ats));
1747 p_hi14a_card->ats_len = len;
1748 }
1749
1750 // reset the PCB block number
1751 iso14_pcb_blocknum = 0;
1752 return 1;
1753 }
1754
1755 void iso14443a_setup() {
1756 // Set up the synchronous serial port
1757 FpgaSetupSsc();
1758 // Start from off (no field generated)
1759 // Signal field is off with the appropriate LED
1760 // LED_D_OFF();
1761 // FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1762 // SpinDelay(50);
1763
1764 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
1765
1766 // Now give it time to spin up.
1767 // Signal field is on with the appropriate LED
1768 LED_D_ON();
1769 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1770 SpinDelay(7); // iso14443-3 specifies 5ms max.
1771
1772 iso14a_timeout = 2048; //default
1773 }
1774
1775 int iso14_apdu(uint8_t * cmd, size_t cmd_len, void * data) {
1776 uint8_t real_cmd[cmd_len+4];
1777 real_cmd[0] = 0x0a; //I-Block
1778 // put block number into the PCB
1779 real_cmd[0] |= iso14_pcb_blocknum;
1780 real_cmd[1] = 0x00; //CID: 0 //FIXME: allow multiple selected cards
1781 memcpy(real_cmd+2, cmd, cmd_len);
1782 AppendCrc14443a(real_cmd,cmd_len+2);
1783
1784 ReaderTransmit(real_cmd, cmd_len+4, NULL);
1785 size_t len = ReaderReceive(data);
1786 uint8_t * data_bytes = (uint8_t *) data;
1787 if (!len)
1788 return 0; //DATA LINK ERROR
1789 // if we received an I- or R(ACK)-Block with a block number equal to the
1790 // current block number, toggle the current block number
1791 else if (len >= 4 // PCB+CID+CRC = 4 bytes
1792 && ((data_bytes[0] & 0xC0) == 0 // I-Block
1793 || (data_bytes[0] & 0xD0) == 0x80) // R-Block with ACK bit set to 0
1794 && (data_bytes[0] & 0x01) == iso14_pcb_blocknum) // equal block numbers
1795 {
1796 iso14_pcb_blocknum ^= 1;
1797 }
1798
1799 return len;
1800 }
1801
1802 //-----------------------------------------------------------------------------
1803 // Read an ISO 14443a tag. Send out commands and store answers.
1804 //
1805 //-----------------------------------------------------------------------------
1806 void ReaderIso14443a(UsbCommand * c)
1807 {
1808 iso14a_command_t param = c->arg[0];
1809 uint8_t * cmd = c->d.asBytes;
1810 size_t len = c->arg[1];
1811 size_t lenbits = c->arg[2];
1812 uint32_t arg0 = 0;
1813 byte_t buf[USB_CMD_DATA_SIZE];
1814
1815 if(param & ISO14A_CONNECT) {
1816 iso14a_clear_trace();
1817 }
1818 iso14a_set_tracing(true);
1819
1820 if(param & ISO14A_REQUEST_TRIGGER) {
1821 iso14a_set_trigger(1);
1822 }
1823
1824 if(param & ISO14A_CONNECT) {
1825 iso14443a_setup();
1826 if(!(param & ISO14A_NO_SELECT)) {
1827 iso14a_card_select_t *card = (iso14a_card_select_t*)buf;
1828 arg0 = iso14443a_select_card(NULL,card,NULL);
1829 cmd_send(CMD_ACK,arg0,card->uidlen,0,buf,sizeof(iso14a_card_select_t));
1830 }
1831 }
1832
1833 if(param & ISO14A_SET_TIMEOUT) {
1834 iso14a_timeout = c->arg[2];
1835 }
1836
1837 if(param & ISO14A_SET_TIMEOUT) {
1838 iso14a_timeout = c->arg[2];
1839 }
1840
1841 if(param & ISO14A_APDU) {
1842 arg0 = iso14_apdu(cmd, len, buf);
1843 cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
1844 }
1845
1846 if(param & ISO14A_RAW) {
1847 if(param & ISO14A_APPEND_CRC) {
1848 AppendCrc14443a(cmd,len);
1849 len += 2;
1850 }
1851 if(lenbits>0) {
1852 ReaderTransmitBitsPar(cmd,lenbits,GetParity(cmd,lenbits/8), NULL);
1853 } else {
1854 ReaderTransmit(cmd,len, NULL);
1855 }
1856 arg0 = ReaderReceive(buf);
1857 cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
1858 }
1859
1860 if(param & ISO14A_REQUEST_TRIGGER) {
1861 iso14a_set_trigger(0);
1862 }
1863
1864 if(param & ISO14A_NO_DISCONNECT) {
1865 return;
1866 }
1867
1868 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
1869 LEDsoff();
1870 }
1871
1872
1873 // Determine the distance between two nonces.
1874 // Assume that the difference is small, but we don't know which is first.
1875 // Therefore try in alternating directions.
1876 int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
1877
1878 uint16_t i;
1879 uint32_t nttmp1, nttmp2;
1880
1881 if (nt1 == nt2) return 0;
1882
1883 nttmp1 = nt1;
1884 nttmp2 = nt2;
1885
1886 for (i = 1; i < 32768; i++) {
1887 nttmp1 = prng_successor(nttmp1, 1);
1888 if (nttmp1 == nt2) return i;
1889 nttmp2 = prng_successor(nttmp2, 1);
1890 if (nttmp2 == nt1) return -i;
1891 }
1892
1893 return(-99999); // either nt1 or nt2 are invalid nonces
1894 }
1895
1896
1897 //-----------------------------------------------------------------------------
1898 // Recover several bits of the cypher stream. This implements (first stages of)
1899 // the algorithm described in "The Dark Side of Security by Obscurity and
1900 // Cloning MiFare Classic Rail and Building Passes, Anywhere, Anytime"
1901 // (article by Nicolas T. Courtois, 2009)
1902 //-----------------------------------------------------------------------------
1903 void ReaderMifare(bool first_try)
1904 {
1905 // Mifare AUTH
1906 uint8_t mf_auth[] = { 0x60,0x00,0xf5,0x7b };
1907 uint8_t mf_nr_ar[] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
1908 static uint8_t mf_nr_ar3;
1909
1910 uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);
1911 traceLen = 0;
1912 tracing = false;
1913
1914 byte_t nt_diff = 0;
1915 byte_t par = 0;
1916 //byte_t par_mask = 0xff;
1917 static byte_t par_low = 0;
1918 bool led_on = TRUE;
1919 uint8_t uid[10];
1920 uint32_t cuid;
1921
1922 uint32_t nt, previous_nt;
1923 static uint32_t nt_attacked = 0;
1924 byte_t par_list[8] = {0,0,0,0,0,0,0,0};
1925 byte_t ks_list[8] = {0,0,0,0,0,0,0,0};
1926
1927 static uint32_t sync_time;
1928 static uint32_t sync_cycles;
1929 int catch_up_cycles = 0;
1930 int last_catch_up = 0;
1931 uint16_t consecutive_resyncs = 0;
1932 int isOK = 0;
1933
1934
1935
1936 if (first_try) {
1937 StartCountMifare();
1938 mf_nr_ar3 = 0;
1939 iso14443a_setup();
1940 while((GetCountMifare() & 0xffff0000) != 0x10000); // wait for counter to reset and "warm up"
1941 sync_time = GetCountMifare() & 0xfffffff8;
1942 sync_cycles = 65536; // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).
1943 nt_attacked = 0;
1944 nt = 0;
1945 par = 0;
1946 }
1947 else {
1948 // we were unsuccessful on a previous call. Try another READER nonce (first 3 parity bits remain the same)
1949 // nt_attacked = prng_successor(nt_attacked, 1);
1950 mf_nr_ar3++;
1951 mf_nr_ar[3] = mf_nr_ar3;
1952 par = par_low;
1953 }
1954
1955 LED_A_ON();
1956 LED_B_OFF();
1957 LED_C_OFF();
1958
1959
1960 for(uint16_t i = 0; TRUE; i++) {
1961
1962 WDT_HIT();
1963
1964 // Test if the action was cancelled
1965 if(BUTTON_PRESS()) {
1966 break;
1967 }
1968
1969 LED_C_ON();
1970
1971 if(!iso14443a_select_card(uid, NULL, &cuid)) {
1972 if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Can't select card");
1973 continue;
1974 }
1975
1976 //keep the card active
1977 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
1978
1979 // CodeIso14443aBitsAsReaderPar(mf_auth, sizeof(mf_auth)*8, GetParity(mf_auth, sizeof(mf_auth)*8));
1980
1981 sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles;
1982 catch_up_cycles = 0;
1983
1984 // if we missed the sync time already, advance to the next nonce repeat
1985 while(GetCountMifare() > sync_time) {
1986 sync_time = (sync_time & 0xfffffff8) + sync_cycles;
1987 }
1988
1989 // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked)
1990 ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
1991
1992 // Receive the (4 Byte) "random" nonce
1993 if (!ReaderReceive(receivedAnswer)) {
1994 if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Couldn't receive tag nonce");
1995 continue;
1996 }
1997
1998 previous_nt = nt;
1999 nt = bytes_to_num(receivedAnswer, 4);
2000
2001 // Transmit reader nonce with fake par
2002 ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar), par, NULL);
2003
2004 if (first_try && previous_nt && !nt_attacked) { // we didn't calibrate our clock yet
2005 int nt_distance = dist_nt(previous_nt, nt);
2006 if (nt_distance == 0) {
2007 nt_attacked = nt;
2008 }
2009 else {
2010 if (nt_distance == -99999) { // invalid nonce received, try again
2011 continue;
2012 }
2013 sync_cycles = (sync_cycles - nt_distance);
2014 if (MF_DBGLEVEL >= 3) Dbprintf("calibrating in cycle %d. nt_distance=%d, Sync_cycles: %d\n", i, nt_distance, sync_cycles);
2015 continue;
2016 }
2017 }
2018
2019 if ((nt != nt_attacked) && nt_attacked) { // we somehow lost sync. Try to catch up again...
2020 catch_up_cycles = -dist_nt(nt_attacked, nt);
2021 if (catch_up_cycles == 99999) { // invalid nonce received. Don't resync on that one.
2022 catch_up_cycles = 0;
2023 continue;
2024 }
2025 if (catch_up_cycles == last_catch_up) {
2026 consecutive_resyncs++;
2027 }
2028 else {
2029 last_catch_up = catch_up_cycles;
2030 consecutive_resyncs = 0;
2031 }
2032 if (consecutive_resyncs < 3) {
2033 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);
2034 }
2035 else {
2036 sync_cycles = sync_cycles + catch_up_cycles;
2037 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);
2038 }
2039 continue;
2040 }
2041
2042 consecutive_resyncs = 0;
2043
2044 // Receive answer. This will be a 4 Bit NACK when the 8 parity bits are OK after decoding
2045 if (ReaderReceive(receivedAnswer))
2046 {
2047 catch_up_cycles = 8; // the PRNG is delayed by 8 cycles due to the NAC (4Bits = 0x05 encrypted) transfer
2048
2049 if (nt_diff == 0)
2050 {
2051 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
2052 }
2053
2054 led_on = !led_on;
2055 if(led_on) LED_B_ON(); else LED_B_OFF();
2056
2057 par_list[nt_diff] = par;
2058 ks_list[nt_diff] = receivedAnswer[0] ^ 0x05;
2059
2060 // Test if the information is complete
2061 if (nt_diff == 0x07) {
2062 isOK = 1;
2063 break;
2064 }
2065
2066 nt_diff = (nt_diff + 1) & 0x07;
2067 mf_nr_ar[3] = (mf_nr_ar[3] & 0x1F) | (nt_diff << 5);
2068 par = par_low;
2069 } else {
2070 if (nt_diff == 0 && first_try)
2071 {
2072 par++;
2073 } else {
2074 par = (((par >> 3) + 1) << 3) | par_low;
2075 }
2076 }
2077 }
2078
2079 LogTrace((const uint8_t *)&nt, 4, 0, GetParity((const uint8_t *)&nt, 4), TRUE);
2080 LogTrace(par_list, 8, 0, GetParity(par_list, 8), TRUE);
2081 LogTrace(ks_list, 8, 0, GetParity(ks_list, 8), TRUE);
2082
2083 mf_nr_ar[3] &= 0x1F;
2084
2085 byte_t buf[28];
2086 memcpy(buf + 0, uid, 4);
2087 num_to_bytes(nt, 4, buf + 4);
2088 memcpy(buf + 8, par_list, 8);
2089 memcpy(buf + 16, ks_list, 8);
2090 memcpy(buf + 24, mf_nr_ar, 4);
2091
2092 cmd_send(CMD_ACK,isOK,0,0,buf,28);
2093
2094 // Thats it...
2095 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
2096 LEDsoff();
2097 tracing = TRUE;
2098 }
2099
2100 //-----------------------------------------------------------------------------
2101 // MIFARE 1K simulate.
2102 //
2103 //-----------------------------------------------------------------------------
2104 void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain)
2105 {
2106 int cardSTATE = MFEMUL_NOFIELD;
2107 int _7BUID = 0;
2108 int vHf = 0; // in mV
2109 //int nextCycleTimeout = 0;
2110 int res;
2111 // uint32_t timer = 0;
2112 uint32_t selTimer = 0;
2113 uint32_t authTimer = 0;
2114 uint32_t par = 0;
2115 int len = 0;
2116 uint8_t cardWRBL = 0;
2117 uint8_t cardAUTHSC = 0;
2118 uint8_t cardAUTHKEY = 0xff; // no authentication
2119 //uint32_t cardRn = 0;
2120 uint32_t cardRr = 0;
2121 uint32_t cuid = 0;
2122 //uint32_t rn_enc = 0;
2123 uint32_t ans = 0;
2124 uint32_t cardINTREG = 0;
2125 uint8_t cardINTBLOCK = 0;
2126 struct Crypto1State mpcs = {0, 0};
2127 struct Crypto1State *pcs;
2128 pcs = &mpcs;
2129
2130 uint8_t* receivedCmd = eml_get_bigbufptr_recbuf();
2131 uint8_t *response = eml_get_bigbufptr_sendbuf();
2132
2133 static uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID
2134
2135 static uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62};
2136 static uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; // !!!
2137
2138 static uint8_t rSAK[] = {0x08, 0xb6, 0xdd};
2139 static uint8_t rSAK1[] = {0x04, 0xda, 0x17};
2140
2141 static uint8_t rAUTH_NT[] = {0x01, 0x02, 0x03, 0x04};
2142 // static uint8_t rAUTH_NT[] = {0x1a, 0xac, 0xff, 0x4f};
2143 static uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00};
2144
2145 // clear trace
2146 traceLen = 0;
2147 tracing = true;
2148
2149 // Authenticate response - nonce
2150 uint32_t nonce = bytes_to_num(rAUTH_NT, 4);
2151
2152 // get UID from emul memory
2153 emlGetMemBt(receivedCmd, 7, 1);
2154 _7BUID = !(receivedCmd[0] == 0x00);
2155 if (!_7BUID) { // ---------- 4BUID
2156 rATQA[0] = 0x04;
2157
2158 emlGetMemBt(rUIDBCC1, 0, 4);
2159 rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
2160 } else { // ---------- 7BUID
2161 rATQA[0] = 0x44;
2162
2163 rUIDBCC1[0] = 0x88;
2164 emlGetMemBt(&rUIDBCC1[1], 0, 3);
2165 rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
2166 emlGetMemBt(rUIDBCC2, 3, 4);
2167 rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3];
2168 }
2169
2170 // -------------------------------------- test area
2171
2172 // -------------------------------------- END test area
2173 // start mkseconds counter
2174 StartCountUS();
2175
2176 // We need to listen to the high-frequency, peak-detected path.
2177 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
2178 FpgaSetupSsc();
2179
2180 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
2181 SpinDelay(200);
2182
2183 if (MF_DBGLEVEL >= 1) Dbprintf("Started. 7buid=%d", _7BUID);
2184 // calibrate mkseconds counter
2185 GetDeltaCountUS();
2186 while (true) {
2187 WDT_HIT();
2188
2189 if(BUTTON_PRESS()) {
2190 break;
2191 }
2192
2193 // find reader field
2194 // Vref = 3300mV, and an 10:1 voltage divider on the input
2195 // can measure voltages up to 33000 mV
2196 if (cardSTATE == MFEMUL_NOFIELD) {
2197 vHf = (33000 * AvgAdc(ADC_CHAN_HF)) >> 10;
2198 if (vHf > MF_MINFIELDV) {
2199 cardSTATE_TO_IDLE();
2200 LED_A_ON();
2201 }
2202 }
2203
2204 if (cardSTATE != MFEMUL_NOFIELD) {
2205 res = EmGetCmd(receivedCmd, &len, RECV_CMD_SIZE); // (+ nextCycleTimeout)
2206 if (res == 2) {
2207 cardSTATE = MFEMUL_NOFIELD;
2208 LEDsoff();
2209 continue;
2210 }
2211 if(res) break;
2212 }
2213
2214 //nextCycleTimeout = 0;
2215
2216 // if (len) Dbprintf("len:%d cmd: %02x %02x %02x %02x", len, receivedCmd[0], receivedCmd[1], receivedCmd[2], receivedCmd[3]);
2217
2218 if (len != 4 && cardSTATE != MFEMUL_NOFIELD) { // len != 4 <---- speed up the code 4 authentication
2219 // REQ or WUP request in ANY state and WUP in HALTED state
2220 if (len == 1 && ((receivedCmd[0] == 0x26 && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == 0x52)) {
2221 selTimer = GetTickCount();
2222 EmSendCmdEx(rATQA, sizeof(rATQA), (receivedCmd[0] == 0x52));
2223 cardSTATE = MFEMUL_SELECT1;
2224
2225 // init crypto block
2226 LED_B_OFF();
2227 LED_C_OFF();
2228 crypto1_destroy(pcs);
2229 cardAUTHKEY = 0xff;
2230 }
2231 }
2232
2233 switch (cardSTATE) {
2234 case MFEMUL_NOFIELD:{
2235 break;
2236 }
2237 case MFEMUL_HALTED:{
2238 break;
2239 }
2240 case MFEMUL_IDLE:{
2241 break;
2242 }
2243 case MFEMUL_SELECT1:{
2244 // select all
2245 if (len == 2 && (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x20)) {
2246 EmSendCmd(rUIDBCC1, sizeof(rUIDBCC1));
2247 break;
2248 }
2249
2250 // select card
2251 if (len == 9 &&
2252 (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC1, 4) == 0)) {
2253 if (!_7BUID)
2254 EmSendCmd(rSAK, sizeof(rSAK));
2255 else
2256 EmSendCmd(rSAK1, sizeof(rSAK1));
2257
2258 cuid = bytes_to_num(rUIDBCC1, 4);
2259 if (!_7BUID) {
2260 cardSTATE = MFEMUL_WORK;
2261 LED_B_ON();
2262 if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol1 time: %d", GetTickCount() - selTimer);
2263 break;
2264 } else {
2265 cardSTATE = MFEMUL_SELECT2;
2266 break;
2267 }
2268 }
2269
2270 break;
2271 }
2272 case MFEMUL_SELECT2:{
2273 if (!len) break;
2274
2275 if (len == 2 && (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x20)) {
2276 EmSendCmd(rUIDBCC2, sizeof(rUIDBCC2));
2277 break;
2278 }
2279
2280 // select 2 card
2281 if (len == 9 &&
2282 (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC2, 4) == 0)) {
2283 EmSendCmd(rSAK, sizeof(rSAK));
2284
2285 cuid = bytes_to_num(rUIDBCC2, 4);
2286 cardSTATE = MFEMUL_WORK;
2287 LED_B_ON();
2288 if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol2 time: %d", GetTickCount() - selTimer);
2289 break;
2290 }
2291
2292 // i guess there is a command). go into the work state.
2293 if (len != 4) break;
2294 cardSTATE = MFEMUL_WORK;
2295 goto lbWORK;
2296 }
2297 case MFEMUL_AUTH1:{
2298 if (len == 8) {
2299 // --- crypto
2300 //rn_enc = bytes_to_num(receivedCmd, 4);
2301 //cardRn = rn_enc ^ crypto1_word(pcs, rn_enc , 1);
2302 cardRr = bytes_to_num(&receivedCmd[4], 4) ^ crypto1_word(pcs, 0, 0);
2303 // test if auth OK
2304 if (cardRr != prng_successor(nonce, 64)){
2305 if (MF_DBGLEVEL >= 4) Dbprintf("AUTH FAILED. cardRr=%08x, succ=%08x", cardRr, prng_successor(nonce, 64));
2306 cardSTATE_TO_IDLE();
2307 break;
2308 }
2309 ans = prng_successor(nonce, 96) ^ crypto1_word(pcs, 0, 0);
2310 num_to_bytes(ans, 4, rAUTH_AT);
2311 // --- crypto
2312 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
2313 cardSTATE = MFEMUL_AUTH2;
2314 } else {
2315 cardSTATE_TO_IDLE();
2316 }
2317 if (cardSTATE != MFEMUL_AUTH2) break;
2318 }
2319 case MFEMUL_AUTH2:{
2320 LED_C_ON();
2321 cardSTATE = MFEMUL_WORK;
2322 if (MF_DBGLEVEL >= 4) Dbprintf("AUTH COMPLETED. sec=%d, key=%d time=%d", cardAUTHSC, cardAUTHKEY, GetTickCount() - authTimer);
2323 break;
2324 }
2325 case MFEMUL_WORK:{
2326 lbWORK: if (len == 0) break;
2327
2328 if (cardAUTHKEY == 0xff) {
2329 // first authentication
2330 if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) {
2331 authTimer = GetTickCount();
2332
2333 cardAUTHSC = receivedCmd[1] / 4; // received block num
2334 cardAUTHKEY = receivedCmd[0] - 0x60;
2335
2336 // --- crypto
2337 crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
2338 ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0);
2339 num_to_bytes(nonce, 4, rAUTH_AT);
2340 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
2341 // --- crypto
2342
2343 // last working revision
2344 // EmSendCmd14443aRaw(resp1, resp1Len, 0);
2345 // LogTrace(NULL, 0, GetDeltaCountUS(), 0, true);
2346
2347 cardSTATE = MFEMUL_AUTH1;
2348 //nextCycleTimeout = 10;
2349 break;
2350 }
2351 } else {
2352 // decrypt seqence
2353 mf_crypto1_decrypt(pcs, receivedCmd, len);
2354
2355 // nested authentication
2356 if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) {
2357 authTimer = GetTickCount();
2358
2359 cardAUTHSC = receivedCmd[1] / 4; // received block num
2360 cardAUTHKEY = receivedCmd[0] - 0x60;
2361
2362 // --- crypto
2363 crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
2364 ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0);
2365 num_to_bytes(ans, 4, rAUTH_AT);
2366 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
2367 // --- crypto
2368
2369 cardSTATE = MFEMUL_AUTH1;
2370 //nextCycleTimeout = 10;
2371 break;
2372 }
2373 }
2374
2375 // rule 13 of 7.5.3. in ISO 14443-4. chaining shall be continued
2376 // BUT... ACK --> NACK
2377 if (len == 1 && receivedCmd[0] == CARD_ACK) {
2378 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2379 break;
2380 }
2381
2382 // rule 12 of 7.5.3. in ISO 14443-4. R(NAK) --> R(ACK)
2383 if (len == 1 && receivedCmd[0] == CARD_NACK_NA) {
2384 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2385 break;
2386 }
2387
2388 // read block
2389 if (len == 4 && receivedCmd[0] == 0x30) {
2390 if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
2391 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2392 break;
2393 }
2394 emlGetMem(response, receivedCmd[1], 1);
2395 AppendCrc14443a(response, 16);
2396 mf_crypto1_encrypt(pcs, response, 18, &par);
2397 EmSendCmdPar(response, 18, par);
2398 break;
2399 }
2400
2401 // write block
2402 if (len == 4 && receivedCmd[0] == 0xA0) {
2403 if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
2404 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2405 break;
2406 }
2407 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2408 //nextCycleTimeout = 50;
2409 cardSTATE = MFEMUL_WRITEBL2;
2410 cardWRBL = receivedCmd[1];
2411 break;
2412 }
2413
2414 // works with cardINTREG
2415
2416 // increment, decrement, restore
2417 if (len == 4 && (receivedCmd[0] == 0xC0 || receivedCmd[0] == 0xC1 || receivedCmd[0] == 0xC2)) {
2418 if (receivedCmd[1] >= 16 * 4 ||
2419 receivedCmd[1] / 4 != cardAUTHSC ||
2420 emlCheckValBl(receivedCmd[1])) {
2421 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2422 break;
2423 }
2424 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2425 if (receivedCmd[0] == 0xC1)
2426 cardSTATE = MFEMUL_INTREG_INC;
2427 if (receivedCmd[0] == 0xC0)
2428 cardSTATE = MFEMUL_INTREG_DEC;
2429 if (receivedCmd[0] == 0xC2)
2430 cardSTATE = MFEMUL_INTREG_REST;
2431 cardWRBL = receivedCmd[1];
2432
2433 break;
2434 }
2435
2436
2437 // transfer
2438 if (len == 4 && receivedCmd[0] == 0xB0) {
2439 if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
2440 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2441 break;
2442 }
2443
2444 if (emlSetValBl(cardINTREG, cardINTBLOCK, receivedCmd[1]))
2445 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2446 else
2447 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2448
2449 break;
2450 }
2451
2452 // halt
2453 if (len == 4 && (receivedCmd[0] == 0x50 && receivedCmd[1] == 0x00)) {
2454 LED_B_OFF();
2455 LED_C_OFF();
2456 cardSTATE = MFEMUL_HALTED;
2457 if (MF_DBGLEVEL >= 4) Dbprintf("--> HALTED. Selected time: %d ms", GetTickCount() - selTimer);
2458 break;
2459 }
2460
2461 // command not allowed
2462 if (len == 4) {
2463 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2464 break;
2465 }
2466
2467 // case break
2468 break;
2469 }
2470 case MFEMUL_WRITEBL2:{
2471 if (len == 18){
2472 mf_crypto1_decrypt(pcs, receivedCmd, len);
2473 emlSetMem(receivedCmd, cardWRBL, 1);
2474 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
2475 cardSTATE = MFEMUL_WORK;
2476 break;
2477 } else {
2478 cardSTATE_TO_IDLE();
2479 break;
2480 }
2481 break;
2482 }
2483
2484 case MFEMUL_INTREG_INC:{
2485 mf_crypto1_decrypt(pcs, receivedCmd, len);
2486 memcpy(&ans, receivedCmd, 4);
2487 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
2488 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2489 cardSTATE_TO_IDLE();
2490 break;
2491 }
2492 cardINTREG = cardINTREG + ans;
2493 cardSTATE = MFEMUL_WORK;
2494 break;
2495 }
2496 case MFEMUL_INTREG_DEC:{
2497 mf_crypto1_decrypt(pcs, receivedCmd, len);
2498 memcpy(&ans, receivedCmd, 4);
2499 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
2500 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2501 cardSTATE_TO_IDLE();
2502 break;
2503 }
2504 cardINTREG = cardINTREG - ans;
2505 cardSTATE = MFEMUL_WORK;
2506 break;
2507 }
2508 case MFEMUL_INTREG_REST:{
2509 mf_crypto1_decrypt(pcs, receivedCmd, len);
2510 memcpy(&ans, receivedCmd, 4);
2511 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
2512 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
2513 cardSTATE_TO_IDLE();
2514 break;
2515 }
2516 cardSTATE = MFEMUL_WORK;
2517 break;
2518 }
2519 }
2520 }
2521
2522 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
2523 LEDsoff();
2524
2525 // add trace trailer
2526 memset(rAUTH_NT, 0x44, 4);
2527 LogTrace(rAUTH_NT, 4, 0, 0, TRUE);
2528
2529 if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, traceLen);
2530 }
2531
2532 //-----------------------------------------------------------------------------
2533 // MIFARE sniffer.
2534 //
2535 //-----------------------------------------------------------------------------
2536 void RAMFUNC SniffMifare(uint8_t param) {
2537 // param:
2538 // bit 0 - trigger from first card answer
2539 // bit 1 - trigger from first reader 7-bit request
2540
2541 // C(red) A(yellow) B(green)
2542 LEDsoff();
2543 // init trace buffer
2544 iso14a_clear_trace();
2545
2546 // The command (reader -> tag) that we're receiving.
2547 // The length of a received command will in most cases be no more than 18 bytes.
2548 // So 32 should be enough!
2549 uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
2550 // The response (tag -> reader) that we're receiving.
2551 uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET);
2552
2553 // As we receive stuff, we copy it from receivedCmd or receivedResponse
2554 // into trace, along with its length and other annotations.
2555 //uint8_t *trace = (uint8_t *)BigBuf;
2556
2557 // The DMA buffer, used to stream samples from the FPGA
2558 int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET;
2559 int8_t *data = dmaBuf;
2560 int maxDataLen = 0;
2561 int dataLen = 0;
2562
2563 // Set up the demodulator for tag -> reader responses.
2564 Demod.output = receivedResponse;
2565 Demod.len = 0;
2566 Demod.state = DEMOD_UNSYNCD;
2567
2568 // Set up the demodulator for the reader -> tag commands
2569 memset(&Uart, 0, sizeof(Uart));
2570 Uart.output = receivedCmd;
2571 Uart.byteCntMax = 32; // was 100 (greg)//////////////////
2572 Uart.state = STATE_UNSYNCD;
2573
2574 // Setup for the DMA.
2575 FpgaSetupSsc();
2576 FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
2577
2578 // And put the FPGA in the appropriate mode
2579 // Signal field is off with the appropriate LED
2580 LED_D_OFF();
2581 FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER);
2582 SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
2583
2584 // init sniffer
2585 MfSniffInit();
2586 int sniffCounter = 0;
2587
2588 // And now we loop, receiving samples.
2589 while(true) {
2590 if(BUTTON_PRESS()) {
2591 DbpString("cancelled by button");
2592 goto done;
2593 }
2594
2595 LED_A_ON();
2596 WDT_HIT();
2597
2598 if (++sniffCounter > 65) {
2599 if (MfSniffSend(2000)) {
2600 FpgaEnableSscDma();
2601 }
2602 sniffCounter = 0;
2603 }
2604
2605 int register readBufDataP = data - dmaBuf;
2606 int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR;
2607 if (readBufDataP <= dmaBufDataP){
2608 dataLen = dmaBufDataP - readBufDataP;
2609 } else {
2610 dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP + 1;
2611 }
2612 // test for length of buffer
2613 if(dataLen > maxDataLen) {
2614 maxDataLen = dataLen;
2615 if(dataLen > 400) {
2616 Dbprintf("blew circular buffer! dataLen=0x%x", dataLen);
2617 goto done;
2618 }
2619 }
2620 if(dataLen < 1) continue;
2621
2622 // primary buffer was stopped( <-- we lost data!
2623 if (!AT91C_BASE_PDC_SSC->PDC_RCR) {
2624 AT91C_BASE_PDC_SSC->PDC_RPR = (uint32_t) dmaBuf;
2625 AT91C_BASE_PDC_SSC->PDC_RCR = DMA_BUFFER_SIZE;
2626 Dbprintf("RxEmpty ERROR!!! data length:%d", dataLen); // temporary
2627 }
2628 // secondary buffer sets as primary, secondary buffer was stopped
2629 if (!AT91C_BASE_PDC_SSC->PDC_RNCR) {
2630 AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf;
2631 AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
2632 }
2633
2634 LED_A_OFF();
2635
2636 if(MillerDecoding((data[0] & 0xF0) >> 4)) {
2637 LED_C_INV();
2638 // check - if there is a short 7bit request from reader
2639 if (MfSniffLogic(receivedCmd, Uart.byteCnt, Uart.parityBits, Uart.bitCnt, TRUE)) break;
2640
2641 /* And ready to receive another command. */
2642 Uart.state = STATE_UNSYNCD;
2643
2644 /* And also reset the demod code */
2645 Demod.state = DEMOD_UNSYNCD;
2646 }
2647
2648 if(ManchesterDecoding(data[0] & 0x0F)) {
2649 LED_C_INV();
2650
2651 if (MfSniffLogic(receivedResponse, Demod.len, Demod.parityBits, Demod.bitCount, FALSE)) break;
2652
2653 // And ready to receive another response.
2654 memset(&Demod, 0, sizeof(Demod));
2655 Demod.output = receivedResponse;
2656 Demod.state = DEMOD_UNSYNCD;
2657
2658 /* And also reset the uart code */
2659 Uart.state = STATE_UNSYNCD;
2660 }
2661
2662 data++;
2663 if(data > dmaBuf + DMA_BUFFER_SIZE) {
2664 data = dmaBuf;
2665 }
2666 } // main cycle
2667
2668 DbpString("COMMAND FINISHED");
2669
2670 done:
2671 FpgaDisableSscDma();
2672 MfSniffEnd();
2673
2674 Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.byteCnt=%x Uart.byteCntMax=%x", maxDataLen, Uart.state, Uart.byteCnt, Uart.byteCntMax);
2675 LEDsoff();
2676 }
Impressum, Datenschutz