git.zerfleddert.de Git - proxmark3-svn/blob - client/cmdlf.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <limits.h>
   5 #include "proxusb.h"
   6 #include "data.h"
   7 #include "graph.h"
   8 #include "ui.h"
   9 #include "cmdparser.h"
  10 #include "cmdmain.h"
  11 #include "cmddata.h"
  12 #include "cmdlf.h"
  13 #include "cmdlfhid.h"
  14 #include "cmdlfti.h"
  15 #include "cmdlfem4x.h"
  16
  17 static int CmdHelp(const char *Cmd);
  18
  19 /* send a command before reading */
  20 int CmdLFCommandRead(const char *Cmd)
  21 {
  22   static char dummy[3];
  23
  24   dummy[0]= ' ';
  25
  26   UsbCommand c = {CMD_MOD_THEN_ACQUIRE_RAW_ADC_SAMPLES_125K};
  27   sscanf(Cmd, "%i %i %i %s %s", &c.arg[0], &c.arg[1], &c.arg[2], (char *) &c.d.asBytes,(char *) &dummy+1);
  28   // in case they specified 'h'
  29   strcpy((char *)&c.d.asBytes + strlen((char *)c.d.asBytes), dummy);
  30   SendCommand(&c);
  31   return 0;
  32 }
  33
  34 int CmdFlexdemod(const char *Cmd)
  35 {
  36   int i;
  37   for (i = 0; i < GraphTraceLen; ++i) {
  38     if (GraphBuffer[i] < 0) {
  39       GraphBuffer[i] = -1;
  40     } else {
  41       GraphBuffer[i] = 1;
  42     }
  43   }
  44
  45 #define LONG_WAIT 100
  46   int start;
  47   for (start = 0; start < GraphTraceLen - LONG_WAIT; start++) {
  48     int first = GraphBuffer[start];
  49     for (i = start; i < start + LONG_WAIT; i++) {
  50       if (GraphBuffer[i] != first) {
  51         break;
  52       }
  53     }
  54     if (i == (start + LONG_WAIT)) {
  55       break;
  56     }
  57   }
  58   if (start == GraphTraceLen - LONG_WAIT) {
  59     PrintAndLog("nothing to wait for");
  60     return 0;
  61   }
  62
  63   GraphBuffer[start] = 2;
  64   GraphBuffer[start+1] = -2;
  65
  66   uint8_t bits[64];
  67
  68   int bit;
  69   i = start;
  70   for (bit = 0; bit < 64; bit++) {
  71     int j;
  72     int sum = 0;
  73     for (j = 0; j < 16; j++) {
  74       sum += GraphBuffer[i++];
  75     }
  76     if (sum > 0) {
  77       bits[bit] = 1;
  78     } else {
  79       bits[bit] = 0;
  80     }
  81     PrintAndLog("bit %d sum %d", bit, sum);
  82   }
  83
  84   for (bit = 0; bit < 64; bit++) {
  85     int j;
  86     int sum = 0;
  87     for (j = 0; j < 16; j++) {
  88       sum += GraphBuffer[i++];
  89     }
  90     if (sum > 0 && bits[bit] != 1) {
  91       PrintAndLog("oops1 at %d", bit);
  92     }
  93     if (sum < 0 && bits[bit] != 0) {
  94       PrintAndLog("oops2 at %d", bit);
  95     }
  96   }
  97
  98   GraphTraceLen = 32*64;
  99   i = 0;
 100   int phase = 0;
 101   for (bit = 0; bit < 64; bit++) {
 102     if (bits[bit] == 0) {
 103       phase = 0;
 104     } else {
 105       phase = 1;
 106     }
 107     int j;
 108     for (j = 0; j < 32; j++) {
 109       GraphBuffer[i++] = phase;
 110       phase = !phase;
 111     }
 112   }
 113
 114   RepaintGraphWindow();
 115   return 0;
 116 }
 117
 118 int CmdIndalaDemod(const char *Cmd)
 119 {
 120   // Usage: recover 64bit UID by default, specify "224" as arg to recover a 224bit UID
 121
 122   int state = -1;
 123   int count = 0;
 124   int i, j;
 125   // worst case with GraphTraceLen=64000 is < 4096
 126   // under normal conditions it's < 2048
 127   uint8_t rawbits[4096];
 128   int rawbit = 0;
 129   int worst = 0, worstPos = 0;
 130   PrintAndLog("Expecting a bit less than %d raw bits", GraphTraceLen / 32);
 131   for (i = 0; i < GraphTraceLen-1; i += 2) {
 132     count += 1;
 133     if ((GraphBuffer[i] > GraphBuffer[i + 1]) && (state != 1)) {
 134       if (state == 0) {
 135         for (j = 0; j <  count - 8; j += 16) {
 136           rawbits[rawbit++] = 0;
 137         }
 138         if ((abs(count - j)) > worst) {
 139           worst = abs(count - j);
 140           worstPos = i;
 141         }
 142       }
 143       state = 1;
 144       count = 0;
 145     } else if ((GraphBuffer[i] < GraphBuffer[i + 1]) && (state != 0)) {
 146       if (state == 1) {
 147         for (j = 0; j <  count - 8; j += 16) {
 148           rawbits[rawbit++] = 1;
 149         }
 150         if ((abs(count - j)) > worst) {
 151           worst = abs(count - j);
 152           worstPos = i;
 153         }
 154       }
 155       state = 0;
 156       count = 0;
 157     }
 158   }
 159   PrintAndLog("Recovered %d raw bits", rawbit);
 160   PrintAndLog("worst metric (0=best..7=worst): %d at pos %d", worst, worstPos);
 161
 162   // Finding the start of a UID
 163   int uidlen, long_wait;
 164   if (strcmp(Cmd, "224") == 0) {
 165     uidlen = 224;
 166     long_wait = 30;
 167   } else {
 168     uidlen = 64;
 169     long_wait = 29;
 170   }
 171   int start;
 172   int first = 0;
 173   for (start = 0; start <= rawbit - uidlen; start++) {
 174     first = rawbits[start];
 175     for (i = start; i < start + long_wait; i++) {
 176       if (rawbits[i] != first) {
 177         break;
 178       }
 179     }
 180     if (i == (start + long_wait)) {
 181       break;
 182     }
 183   }
 184   if (start == rawbit - uidlen + 1) {
 185     PrintAndLog("nothing to wait for");
 186     return 0;
 187   }
 188
 189   // Inverting signal if needed
 190   if (first == 1) {
 191     for (i = start; i < rawbit; i++) {
 192       rawbits[i] = !rawbits[i];
 193     }
 194   }
 195
 196   // Dumping UID
 197   uint8_t bits[224];
 198   char showbits[225];
 199   showbits[uidlen]='\0';
 200   int bit;
 201   i = start;
 202   int times = 0;
 203   if (uidlen > rawbit) {
 204     PrintAndLog("Warning: not enough raw bits to get a full UID");
 205     for (bit = 0; bit < rawbit; bit++) {
 206       bits[bit] = rawbits[i++];
 207       // As we cannot know the parity, let's use "." and "/"
 208       showbits[bit] = '.' + bits[bit];
 209     }
 210     showbits[bit+1]='\0';
 211     PrintAndLog("Partial UID=%s", showbits);
 212     return 0;
 213   } else {
 214     for (bit = 0; bit < uidlen; bit++) {
 215       bits[bit] = rawbits[i++];
 216       showbits[bit] = '0' + bits[bit];
 217     }
 218     times = 1;
 219   }
 220   PrintAndLog("UID=%s", showbits);
 221
 222   // Checking UID against next occurences
 223   for (; i + uidlen <= rawbit;) {
 224     int failed = 0;
 225     for (bit = 0; bit < uidlen; bit++) {
 226       if (bits[bit] != rawbits[i++]) {
 227         failed = 1;
 228         break;
 229       }
 230     }
 231     if (failed == 1) {
 232       break;
 233     }
 234     times += 1;
 235   }
 236   PrintAndLog("Occurences: %d (expected %d)", times, (rawbit - start) / uidlen);
 237
 238   // Remodulating for tag cloning
 239   GraphTraceLen = 32*uidlen;
 240   i = 0;
 241   int phase = 0;
 242   for (bit = 0; bit < uidlen; bit++) {
 243     if (bits[bit] == 0) {
 244       phase = 0;
 245     } else {
 246       phase = 1;
 247     }
 248     int j;
 249     for (j = 0; j < 32; j++) {
 250       GraphBuffer[i++] = phase;
 251       phase = !phase;
 252     }
 253   }
 254
 255   RepaintGraphWindow();
 256   return 0;
 257 }
 258
 259 int CmdLFRead(const char *Cmd)
 260 {
 261   UsbCommand c = {CMD_ACQUIRE_RAW_ADC_SAMPLES_125K};
 262   // 'h' means higher-low-frequency, 134 kHz
 263   if(*Cmd == 'h') {
 264     c.arg[0] = 1;
 265   } else if (*Cmd == '\0') {
 266     c.arg[0] = 0;
 267   } else {
 268     PrintAndLog("use 'read' or 'read h'");
 269     return 0;
 270   }
 271   SendCommand(&c);
 272   WaitForResponse(CMD_ACK);
 273   return 0;
 274 }
 275
 276 static void ChkBitstream(const char *str)
 277 {
 278   int i;
 279
 280   /* convert to bitstream if necessary */
 281   for (i = 0; i < (int)(GraphTraceLen / 2); i++)
 282   {
 283     if (GraphBuffer[i] > 1 || GraphBuffer[i] < 0)
 284     {
 285       CmdBitstream(str);
 286       break;
 287     }
 288   }
 289 }
 290
 291 int CmdLFSim(const char *Cmd)
 292 {
 293   int i;
 294   static int gap;
 295
 296   sscanf(Cmd, "%i", &gap);
 297
 298   /* convert to bitstream if necessary */
 299   ChkBitstream(Cmd);
 300
 301   PrintAndLog("Sending data, please wait...");
 302   for (i = 0; i < GraphTraceLen; i += 48) {
 303     UsbCommand c={CMD_DOWNLOADED_SIM_SAMPLES_125K, {i, 0, 0}};
 304     int j;
 305     for (j = 0; j < 48; j++) {
 306       c.d.asBytes[j] = GraphBuffer[i+j];
 307     }
 308     SendCommand(&c);
 309     WaitForResponse(CMD_ACK);
 310   }
 311
 312   PrintAndLog("Starting simulator...");
 313   UsbCommand c = {CMD_SIMULATE_TAG_125K, {GraphTraceLen, gap, 0}};
 314   SendCommand(&c);
 315   return 0;
 316 }
 317
 318 int CmdLFSimBidir(const char *Cmd)
 319 {
 320   /* Set ADC to twice the carrier for a slight supersampling */
 321   UsbCommand c = {CMD_LF_SIMULATE_BIDIR, {47, 384, 0}};
 322   SendCommand(&c);
 323   return 0;
 324 }
 325
 326 /* simulate an LF Manchester encoded tag with specified bitstream, clock rate and inter-id gap */
 327 int CmdLFSimManchester(const char *Cmd)
 328 {
 329   static int clock, gap;
 330   static char data[1024], gapstring[8];
 331
 332   /* get settings/bits */
 333   sscanf(Cmd, "%i %s %i", &clock, &data[0], &gap);
 334
 335   /* clear our graph */
 336   ClearGraph(0);
 337
 338   /* fill it with our bitstream */
 339   for (int i = 0; i < strlen(data) ; ++i)
 340     AppendGraph(0, clock, data[i]- '0');
 341
 342   /* modulate */
 343   CmdManchesterMod("");
 344
 345   /* show what we've done */
 346   RepaintGraphWindow();
 347
 348   /* simulate */
 349   sprintf(&gapstring[0], "%i", gap);
 350   CmdLFSim(gapstring);
 351   return 0;
 352 }
 353
 354 int CmdVchDemod(const char *Cmd)
 355 {
 356   // Is this the entire sync pattern, or does this also include some
 357   // data bits that happen to be the same everywhere? That would be
 358   // lovely to know.
 359   static const int SyncPattern[] = {
 360     1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,
 361     1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
 362     1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,
 363     1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
 364     1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,
 365     1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
 366     1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,
 367     1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
 368     1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,
 369     1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
 370   };
 371
 372   // So first, we correlate for the sync pattern, and mark that.
 373   int bestCorrel = 0, bestPos = 0;
 374   int i;
 375   // It does us no good to find the sync pattern, with fewer than
 376   // 2048 samples after it...
 377   for (i = 0; i < (GraphTraceLen-2048); i++) {
 378     int sum = 0;
 379     int j;
 380     for (j = 0; j < arraylen(SyncPattern); j++) {
 381       sum += GraphBuffer[i+j]*SyncPattern[j];
 382     }
 383     if (sum > bestCorrel) {
 384       bestCorrel = sum;
 385       bestPos = i;
 386     }
 387   }
 388   PrintAndLog("best sync at %d [metric %d]", bestPos, bestCorrel);
 389
 390   char bits[257];
 391   bits[256] = '\0';
 392
 393   int worst = INT_MAX;
 394   int worstPos;
 395
 396   for (i = 0; i < 2048; i += 8) {
 397     int sum = 0;
 398     int j;
 399     for (j = 0; j < 8; j++) {
 400       sum += GraphBuffer[bestPos+i+j];
 401     }
 402     if (sum < 0) {
 403       bits[i/8] = '.';
 404     } else {
 405       bits[i/8] = '1';
 406     }
 407     if(abs(sum) < worst) {
 408       worst = abs(sum);
 409       worstPos = i;
 410     }
 411   }
 412   PrintAndLog("bits:");
 413   PrintAndLog("%s", bits);
 414   PrintAndLog("worst metric: %d at pos %d", worst, worstPos);
 415
 416   if (strcmp(Cmd, "clone")==0) {
 417     GraphTraceLen = 0;
 418     char *s;
 419     for(s = bits; *s; s++) {
 420       int j;
 421       for(j = 0; j < 16; j++) {
 422         GraphBuffer[GraphTraceLen++] = (*s == '1') ? 1 : 0;
 423       }
 424     }
 425     RepaintGraphWindow();
 426   }
 427   return 0;
 428 }
 429
 430 static command_t CommandTable[] =
 431 {
 432   {"help",        CmdHelp,            1, "This help"},
 433   {"cmdread",     CmdLFCommandRead,   0, "<off period> <'0' period> <'1' period> <command> ['h'] -- Modulate LF reader field to send command before read (all periods in microseconds) (option 'h' for 134)"},
 434   {"em4x",        CmdLFEM4X,          1, "{ EM4X RFIDs... }"},
 435   {"flexdemod",   CmdFlexdemod,       1, "Demodulate samples for FlexPass"},
 436   {"hid",         CmdLFHID,           1, "{ HID RFIDs... }"},
 437   {"indalademod", CmdIndalaDemod,     1, "['224'] -- Demodulate samples for Indala 64 bit UID (option '224' for 224 bit)"},
 438   {"read",        CmdLFRead,          0, "['h'] -- Read 125/134 kHz LF ID-only tag (option 'h' for 134)"},
 439   {"sim",         CmdLFSim,           0, "[GAP] -- Simulate LF tag from buffer with optional GAP (in microseconds)"},
 440   {"simbidir",    CmdLFSimBidir,      0, "Simulate LF tag (with bidirectional data transmission between reader and tag)"},
 441   {"simman",      CmdLFSimManchester, 0, "<Clock> <Bitstream> [GAP] Simulate arbitrary Manchester LF tag"},
 442   {"ti",          CmdLFTI,            1, "{ TI RFIDs... }"},
 443   {"vchdemod",    CmdVchDemod,        1, "['clone'] -- Demodulate samples for VeriChip"},
 444   {NULL, NULL, 0, NULL}
 445 };
 446
 447 int CmdLF(const char *Cmd)
 448 {
 449   CmdsParse(CommandTable, Cmd);
 450   return 0;
 451 }
 452
 453 int CmdHelp(const char *Cmd)
 454 {
 455   CmdsHelp(CommandTable);
 456   return 0;
 457 }