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ADD: some defines to make headerfiles behave better.
[proxmark3-svn] / armsrc / pcf7931.c
1 #include "pcf7931.h"
2
3 #define T0_PCF 8 //period for the pcf7931 in us
4 #define ALLOC 16
5
6 int DemodPCF7931(uint8_t **outBlocks) {
7
8 uint8_t bits[256] = {0x00};
9 uint8_t blocks[8][16];
10 uint8_t *dest = BigBuf_get_addr();
11
12 int GraphTraceLen = BigBuf_max_traceLen();
13 if ( GraphTraceLen > 18000 )
14 GraphTraceLen = 18000;
15
16 int i, j, lastval, bitidx, half_switch;
17 int clock = 64;
18 int tolerance = clock / 8;
19 int pmc, block_done;
20 int lc, warnings = 0;
21 int num_blocks = 0;
22 int lmin=128, lmax=128;
23 uint8_t dir;
24 //clear read buffer
25 BigBuf_Clear_keep_EM();
26
27 LFSetupFPGAForADC(95, true);
28 DoAcquisition_default(0, true);
29
30 lmin = 64;
31 lmax = 192;
32
33 i = 2;
34
35 /* Find first local max/min */
36 if(dest[1] > dest[0]) {
37 while(i < GraphTraceLen) {
38 if( !(dest[i] > dest[i-1]) && dest[i] > lmax)
39 break;
40 i++;
41 }
42 dir = 0;
43 }
44 else {
45 while(i < GraphTraceLen) {
46 if( !(dest[i] < dest[i-1]) && dest[i] < lmin)
47 break;
48 i++;
49 }
50 dir = 1;
51 }
52
53 lastval = i++;
54 half_switch = 0;
55 pmc = 0;
56 block_done = 0;
57
58 for (bitidx = 0; i < GraphTraceLen; i++)
59 {
60 if ( (dest[i-1] > dest[i] && dir == 1 && dest[i] > lmax) || (dest[i-1] < dest[i] && dir == 0 && dest[i] < lmin))
61 {
62 lc = i - lastval;
63 lastval = i;
64
65 // Switch depending on lc length:
66 // Tolerance is 1/8 of clock rate (arbitrary)
67 if (ABS(lc-clock/4) < tolerance) {
68 // 16T0
69 if((i - pmc) == lc) { /* 16T0 was previous one */
70 /* It's a PMC ! */
71 i += (128+127+16+32+33+16)-1;
72 lastval = i;
73 pmc = 0;
74 block_done = 1;
75 }
76 else {
77 pmc = i;
78 }
79 } else if (ABS(lc-clock/2) < tolerance) {
80 // 32TO
81 if((i - pmc) == lc) { /* 16T0 was previous one */
82 /* It's a PMC ! */
83 i += (128+127+16+32+33)-1;
84 lastval = i;
85 pmc = 0;
86 block_done = 1;
87 }
88 else if(half_switch == 1) {
89 bits[bitidx++] = 0;
90 half_switch = 0;
91 }
92 else
93 half_switch++;
94 } else if (ABS(lc-clock) < tolerance) {
95 // 64TO
96 bits[bitidx++] = 1;
97 } else {
98 // Error
99 warnings++;
100 if (warnings > 10)
101 {
102 Dbprintf("Error: too many detection errors, aborting.");
103 return 0;
104 }
105 }
106
107 if(block_done == 1) {
108 if(bitidx == 128) {
109 for(j=0; j<16; j++) {
110 blocks[num_blocks][j] = 128*bits[j*8+7]+
111 64*bits[j*8+6]+
112 32*bits[j*8+5]+
113 16*bits[j*8+4]+
114 8*bits[j*8+3]+
115 4*bits[j*8+2]+
116 2*bits[j*8+1]+
117 bits[j*8];
118
119 }
120 num_blocks++;
121 }
122 bitidx = 0;
123 block_done = 0;
124 half_switch = 0;
125 }
126 if(i < GraphTraceLen)
127 dir =(dest[i-1] > dest[i]) ? 0 : 1;
128 }
129 if(bitidx==255)
130 bitidx=0;
131 warnings = 0;
132 if(num_blocks == 4) break;
133 }
134 memcpy(outBlocks, blocks, 16*num_blocks);
135 return num_blocks;
136 }
137
138 int IsBlock0PCF7931(uint8_t *Block) {
139 // Assume RFU means 0 :)
140 if((memcmp(Block, "\x00\x00\x00\x00\x00\x00\x00\x01", 8) == 0) && memcmp(Block+9, "\x00\x00\x00\x00\x00\x00\x00", 7) == 0) // PAC enabled
141 return 1;
142 if((memcmp(Block+9, "\x00\x00\x00\x00\x00\x00\x00", 7) == 0) && Block[7] == 0) // PAC disabled, can it *really* happen ?
143 return 1;
144 return 0;
145 }
146
147 int IsBlock1PCF7931(uint8_t *Block) {
148 // Assume RFU means 0 :)
149 if( Block[10] == 0 &&
150 Block[11] == 0 &&
151 Block[12] == 0 &&
152 Block[13] == 0)
153 if ( (Block[14] & 0x7f) <= 9 && Block[15] <= 9)
154 return 1;
155 return 0;
156 }
157
158 void ReadPCF7931() {
159 uint8_t Blocks[8][17];
160 uint8_t tmpBlocks[4][16];
161 int i, j, ind, ind2, n;
162 int num_blocks = 0;
163 int max_blocks = 8;
164 int ident = 0;
165 int error = 0;
166 int tries = 0;
167
168 memset(Blocks, 0, 8*17*sizeof(uint8_t));
169
170 do {
171 memset(tmpBlocks, 0, 4*16*sizeof(uint8_t));
172 n = DemodPCF7931((uint8_t**)tmpBlocks);
173 if(!n)
174 error++;
175 if(error==10 && num_blocks == 0) {
176 Dbprintf("Error, no tag or bad tag");
177 return;
178 }
179 else if (tries==20 || error==10) {
180 Dbprintf("Error reading the tag");
181 Dbprintf("Here is the partial content");
182 goto end;
183 }
184
185 for(i=0; i<n; i++)
186 Dbprintf("(dbg) %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
187 tmpBlocks[i][0], tmpBlocks[i][1], tmpBlocks[i][2], tmpBlocks[i][3], tmpBlocks[i][4], tmpBlocks[i][5], tmpBlocks[i][6], tmpBlocks[i][7],
188 tmpBlocks[i][8], tmpBlocks[i][9], tmpBlocks[i][10], tmpBlocks[i][11], tmpBlocks[i][12], tmpBlocks[i][13], tmpBlocks[i][14], tmpBlocks[i][15]);
189 if(!ident) {
190 for(i=0; i<n; i++) {
191 if(IsBlock0PCF7931(tmpBlocks[i])) {
192 // Found block 0 ?
193 if(i < n-1 && IsBlock1PCF7931(tmpBlocks[i+1])) {
194 // Found block 1!
195 // \o/
196 ident = 1;
197 memcpy(Blocks[0], tmpBlocks[i], 16);
198 Blocks[0][ALLOC] = 1;
199 memcpy(Blocks[1], tmpBlocks[i+1], 16);
200 Blocks[1][ALLOC] = 1;
201 max_blocks = MAX((Blocks[1][14] & 0x7f), Blocks[1][15]) + 1;
202 // Debug print
203 Dbprintf("(dbg) Max blocks: %d", max_blocks);
204 num_blocks = 2;
205 // Handle following blocks
206 for(j=i+2, ind2=2; j!=i; j++, ind2++, num_blocks++) {
207 if(j==n) j=0;
208 if(j==i) break;
209 memcpy(Blocks[ind2], tmpBlocks[j], 16);
210 Blocks[ind2][ALLOC] = 1;
211 }
212 break;
213 }
214 }
215 }
216 }
217 else {
218 for(i=0; i<n; i++) { // Look for identical block in known blocks
219 if(memcmp(tmpBlocks[i], "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16)) { // Block is not full of 00
220 for(j=0; j<max_blocks; j++) {
221 if(Blocks[j][ALLOC] == 1 && !memcmp(tmpBlocks[i], Blocks[j], 16)) {
222 // Found an identical block
223 for(ind=i-1,ind2=j-1; ind >= 0; ind--,ind2--) {
224 if(ind2 < 0)
225 ind2 = max_blocks;
226 if(!Blocks[ind2][ALLOC]) { // Block ind2 not already found
227 // Dbprintf("Tmp %d -> Block %d", ind, ind2);
228 memcpy(Blocks[ind2], tmpBlocks[ind], 16);
229 Blocks[ind2][ALLOC] = 1;
230 num_blocks++;
231 if(num_blocks == max_blocks) goto end;
232 }
233 }
234 for(ind=i+1,ind2=j+1; ind < n; ind++,ind2++) {
235 if(ind2 > max_blocks)
236 ind2 = 0;
237 if(!Blocks[ind2][ALLOC]) { // Block ind2 not already found
238 // Dbprintf("Tmp %d -> Block %d", ind, ind2);
239 memcpy(Blocks[ind2], tmpBlocks[ind], 16);
240 Blocks[ind2][ALLOC] = 1;
241 num_blocks++;
242 if(num_blocks == max_blocks) goto end;
243 }
244 }
245 }
246 }
247 }
248 }
249 }
250 tries++;
251 if (BUTTON_PRESS()) return;
252 } while (num_blocks != max_blocks);
253 end:
254 Dbprintf("-----------------------------------------");
255 Dbprintf("Memory content:");
256 Dbprintf("-----------------------------------------");
257 for(i=0; i<max_blocks; i++) {
258 if(Blocks[i][ALLOC]==1)
259 Dbprintf("%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
260 Blocks[i][0], Blocks[i][1], Blocks[i][2], Blocks[i][3], Blocks[i][4], Blocks[i][5], Blocks[i][6], Blocks[i][7],
261 Blocks[i][8], Blocks[i][9], Blocks[i][10], Blocks[i][11], Blocks[i][12], Blocks[i][13], Blocks[i][14], Blocks[i][15]);
262 else
263 Dbprintf("<missing block %d>", i);
264 }
265 Dbprintf("-----------------------------------------");
266
267 cmd_send(CMD_ACK,0,0,0,0,0);
268 }
269
270
271 /* Write on a byte of a PCF7931 tag
272 * @param address : address of the block to write
273 @param byte : address of the byte to write
274 @param data : data to write
275 */
276 void WritePCF7931(uint8_t pass1, uint8_t pass2, uint8_t pass3, uint8_t pass4, uint8_t pass5, uint8_t pass6, uint8_t pass7, uint16_t init_delay, int32_t l, int32_t p, uint8_t address, uint8_t byte, uint8_t data)
277 {
278 uint32_t tab[1024] = {0}; // data times frame
279 uint32_t u = 0;
280 uint8_t parity = 0;
281 bool comp = 0;
282
283 //BUILD OF THE DATA FRAME
284
285 //alimentation of the tag (time for initializing)
286 AddPatternPCF7931(init_delay, 0, 8192/2*T0_PCF, tab);
287
288 //PMC
289 Dbprintf("Initialization delay : %d us", init_delay);
290 AddPatternPCF7931(8192/2*T0_PCF + 319*T0_PCF+70, 3*T0_PCF, 29*T0_PCF, tab);
291
292 Dbprintf("Offsets : %d us on the low pulses width, %d us on the low pulses positions", l, p);
293
294 //password indication bit
295 AddBitPCF7931(1, tab, l, p);
296
297 //password (on 56 bits)
298 Dbprintf("Password (LSB first on each byte) : %02x %02x %02x %02x %02x %02x %02x", pass1,pass2,pass3,pass4,pass5,pass6,pass7);
299 AddBytePCF7931(pass1, tab, l, p);
300 AddBytePCF7931(pass2, tab, l, p);
301 AddBytePCF7931(pass3, tab, l, p);
302 AddBytePCF7931(pass4, tab, l, p);
303 AddBytePCF7931(pass5, tab, l, p);
304 AddBytePCF7931(pass6, tab, l, p);
305 AddBytePCF7931(pass7, tab, l, p);
306
307
308 //programming mode (0 or 1)
309 AddBitPCF7931(0, tab, l, p);
310
311 //block adress on 6 bits
312 Dbprintf("Block address : %02x", address);
313 for (u=0; u<6; u++)
314 {
315 if (address&(1<<u)) { // bit 1
316 parity++;
317 AddBitPCF7931(1, tab, l, p);
318 } else{ // bit 0
319 AddBitPCF7931(0, tab, l, p);
320 }
321 }
322
323 //byte address on 4 bits
324 Dbprintf("Byte address : %02x", byte);
325 for (u=0; u<4; u++)
326 {
327 if (byte&(1<<u)) { // bit 1
328 parity++;
329 AddBitPCF7931(1, tab, l, p);
330 } else{ // bit 0
331 AddBitPCF7931(0, tab, l, p);
332 }
333 }
334
335 //data on 8 bits
336 Dbprintf("Data : %02x", data);
337 for (u=0; u<8; u++)
338 {
339 if (data&(1<<u)) { // bit 1
340 parity++;
341 AddBitPCF7931(1, tab, l, p);
342 } else{ //bit 0
343 AddBitPCF7931(0, tab, l, p);
344 }
345 }
346
347
348 //parity bit
349 if((parity%2)==0){
350 AddBitPCF7931(0, tab, l, p); //even parity
351 }else{
352 AddBitPCF7931(1, tab, l, p);//odd parity
353 }
354
355 //time access memory
356 AddPatternPCF7931(5120+2680, 0, 0, tab);
357
358 //conversion of the scale time
359 for(u=0;u<500;u++){
360 tab[u]=(tab[u] * 3)/2;
361 }
362
363 //compensation of the counter reload
364 while (!comp){
365 comp = 1;
366 for(u=0;tab[u]!=0;u++){
367 if(tab[u] > 0xFFFF){
368 tab[u] -= 0xFFFF;
369 comp = 0;
370 }
371 }
372 }
373
374 SendCmdPCF7931(tab);
375 }
376
377
378
379 /* Send a trame to a PCF7931 tags
380 * @param tab : array of the data frame
381 */
382
383 void SendCmdPCF7931(uint32_t * tab){
384 uint16_t u=0, tempo=0;
385
386 Dbprintf("Sending data frame...");
387
388 FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
389
390 FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
391
392 FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_PASSTHRU );
393
394 LED_A_ON();
395
396 // steal this pin from the SSP and use it to control the modulation
397 AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DOUT;
398 AT91C_BASE_PIOA->PIO_OER = GPIO_SSC_DOUT;
399
400 //initialization of the timer
401 AT91C_BASE_PMC->PMC_PCER |= (0x1 << AT91C_ID_TC0);
402 AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_TIOA0 | AT91C_TCB_TC2XC2S_NONE;
403 AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // timer disable
404 AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_TIMER_DIV3_CLOCK; //clock at 48/32 MHz
405 AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN;
406 AT91C_BASE_TCB->TCB_BCR = 1;
407
408
409 tempo = AT91C_BASE_TC0->TC_CV;
410 for( u = 0; tab[u] != 0; u += 3){
411
412 // modulate antenna
413 HIGH(GPIO_SSC_DOUT);
414 while(tempo != tab[u]) tempo = AT91C_BASE_TC0->TC_CV;
415
416 // stop modulating antenna
417 LOW(GPIO_SSC_DOUT);
418 while(tempo != tab[u+1]) tempo = AT91C_BASE_TC0->TC_CV;
419
420 // modulate antenna
421 HIGH(GPIO_SSC_DOUT);
422 while(tempo != tab[u+2]) tempo = AT91C_BASE_TC0->TC_CV;
423 }
424
425 LED_A_OFF();
426 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
427 SpinDelay(200);
428
429 AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // timer disable
430 LED(0xFFFF, 1000);
431 }
432
433
434 /* Add a byte for building the data frame of PCF7931 tags
435 * @param b : byte to add
436 * @param tab : array of the data frame
437 * @param l : offset on low pulse width
438 * @param p : offset on low pulse positioning
439 */
440
441 bool AddBytePCF7931(uint8_t byte, uint32_t * tab, int32_t l, int32_t p){
442
443 uint32_t u;
444 for ( u=0; u<8; u++)
445 {
446 if (byte&(1<<u)) { //bit à 1
447 if( AddBitPCF7931(1, tab, l, p)==1) return 1;
448 } else { //bit à 0
449 if (AddBitPCF7931(0, tab, l, p)==1) return 1;
450 }
451 }
452 return 0;
453 }
454
455 /* Add a bits for building the data frame of PCF7931 tags
456 * @param b : bit to add
457 * @param tab : array of the data frame
458 * @param l : offset on low pulse width
459 * @param p : offset on low pulse positioning
460 */
461 bool AddBitPCF7931(bool b, uint32_t * tab, int32_t l, int32_t p){
462 uint8_t u = 0;
463
464 //we put the cursor at the last value of the array
465 for ( u = 0; tab[u] != 0; u += 3 ) { }
466
467 if ( b == 1 ) { //add a bit 1
468 if ( u == 0 )
469 tab[u] = 34 * T0_PCF + p;
470 else
471 tab[u] = 34 * T0_PCF + tab[u-1] + p;
472
473 tab[u+1] = 6 * T0_PCF + tab[u] + l;
474 tab[u+2] = 88 * T0_PCF + tab[u+1] - l - p;
475 return 0;
476 } else { //add a bit 0
477
478 if ( u == 0 )
479 tab[u] = 98 * T0_PCF + p;
480 else
481 tab[u] = 98 * T0_PCF + tab[u-1] + p;
482
483 tab[u+1] = 6 * T0_PCF + tab[u] + l;
484 tab[u+2] = 24 * T0_PCF + tab[u+1] - l - p;
485 return 0;
486 }
487 return 1;
488 }
489
490 /* Add a custom pattern in the data frame
491 * @param a : delay of the first high pulse
492 * @param b : delay of the low pulse
493 * @param c : delay of the last high pulse
494 * @param tab : array of the data frame
495 */
496 bool AddPatternPCF7931(uint32_t a, uint32_t b, uint32_t c, uint32_t * tab){
497 uint32_t u = 0;
498 for(u = 0; tab[u] != 0; u += 3){} //we put the cursor at the last value of the array
499
500 tab[u] = (u == 0) ? a : a + tab[u-1];
501 tab[u+1] = b + tab[u];
502 tab[u+2] = c + tab[u+1];
503
504 return 0;
505 }
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