cvs.zerfleddert.de Git - proxmark3-svn/blob - client/util.c

   1 //-----------------------------------------------------------------------------
   2 // Copyright (C) 2010 iZsh <izsh at fail0verflow.com>
   3 //
   4 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   5 // at your option, any later version. See the LICENSE.txt file for the text of
   6 // the license.
   7 //-----------------------------------------------------------------------------
   8 // utilities
   9 //-----------------------------------------------------------------------------
  10
  11 #include "util.h"
  12
  13 #include <stdint.h>
  14 #include <string.h>
  15 #include <ctype.h>
  16 #include <stdlib.h>
  17 #include <stdio.h>
  18 #include <time.h>
  19 #include "data.h"
  20
  21 #ifdef _WIN32
  22 #include <windows.h>
  23 #endif
  24
  25 #define MAX_BIN_BREAK_LENGTH   (3072+384+1)
  26
  27 #ifndef _WIN32
  28 #include <termios.h>
  29 #include <sys/ioctl.h>
  30 #include <unistd.h>
  31
  32 int ukbhit(void)
  33 {
  34   int cnt = 0;
  35   int error;
  36   static struct termios Otty, Ntty;
  37
  38   if ( tcgetattr(STDIN_FILENO, &Otty) == -1 ) return -1;
  39   Ntty = Otty;
  40
  41   Ntty.c_iflag          = 0x0000;   // input mode
  42   Ntty.c_oflag          = 0x0000;   // output mode
  43   Ntty.c_lflag         &= ~ICANON;  // control mode = raw
  44   Ntty.c_cc[VMIN]       = 1;        // return if at least 1 character is in the queue
  45   Ntty.c_cc[VTIME]      = 0;        // no timeout. Wait forever
  46
  47   if (0 == (error = tcsetattr(STDIN_FILENO, TCSANOW, &Ntty))) {   // set new attributes
  48     error += ioctl(STDIN_FILENO, FIONREAD, &cnt);                 // get number of characters availabe
  49     error += tcsetattr(STDIN_FILENO, TCSANOW, &Otty);             // reset attributes
  50   }
  51
  52   return ( error == 0 ? cnt : -1 );
  53 }
  54
  55 #else
  56
  57 #include <conio.h>
  58 int ukbhit(void) {
  59         return kbhit();
  60 }
  61 #endif
  62
  63 // log files functions
  64 void AddLogLine(char *file, char *extData, char *c) {
  65         FILE *fLog = NULL;
  66     char filename[FILE_PATH_SIZE] = {0x00};
  67     int len = 0;
  68
  69     len = strlen(file);
  70     if (len > FILE_PATH_SIZE) len = FILE_PATH_SIZE;
  71     memcpy(filename, file, len);
  72
  73         fLog = fopen(filename, "a");
  74         if (!fLog) {
  75                 printf("Could not append log file %s", filename);
  76                 return;
  77         }
  78
  79         fprintf(fLog, "%s", extData);
  80         fprintf(fLog, "%s\n", c);
  81         fclose(fLog);
  82 }
  83
  84 void AddLogHex(char *fileName, char *extData, const uint8_t * data, const size_t len){
  85         AddLogLine(fileName, extData, sprint_hex(data, len));
  86 }
  87
  88 void AddLogUint64(char *fileName, char *extData, const uint64_t data) {
  89   char buf[100] = {0};
  90         sprintf(buf, "%x%x", (unsigned int)((data & 0xFFFFFFFF00000000) >> 32), (unsigned int)(data & 0xFFFFFFFF));
  91         AddLogLine(fileName, extData, buf);
  92 }
  93
  94 void AddLogCurrentDT(char *fileName) {
  95         char buff[20];
  96         struct tm *curTime;
  97
  98         time_t now = time(0);
  99         curTime = gmtime(&now);
 100
 101         strftime (buff, sizeof(buff), "%Y-%m-%d %H:%M:%S", curTime);
 102         AddLogLine(fileName, "\nanticollision: ", buff);
 103 }
 104
 105 void FillFileNameByUID(char *fileName, uint8_t * uid, char *ext, int byteCount) {
 106         char * fnameptr = fileName;
 107         memset(fileName, 0x00, 200);
 108
 109         for (int j = 0; j < byteCount; j++, fnameptr += 2)
 110                 sprintf(fnameptr, "%02x", (unsigned int) uid[j]);
 111         sprintf(fnameptr, "%s", ext);
 112 }
 113
 114 void hex_to_buffer(const uint8_t *buf, const uint8_t *hex_data, const size_t hex_len, const size_t hex_max_len,
 115         const size_t min_str_len, const size_t spaces_between, bool uppercase) {
 116
 117         char *tmp = (char *)buf;
 118         size_t i;
 119
 120         int maxLen = ( hex_len > hex_max_len) ? hex_max_len : hex_len;
 121
 122         for (i = 0; i < maxLen; ++i, tmp += 2 + spaces_between) {
 123                 sprintf(tmp, (uppercase) ? "%02X" : "%02x", (unsigned int) hex_data[i]);
 124
 125                 for (int j = 0; j < spaces_between; j++)
 126                         sprintf(tmp + 2 + j, " ");
 127         }
 128
 129         i *= (2 + spaces_between);
 130         int minStrLen = min_str_len > i ? min_str_len : 0;
 131         if (minStrLen > hex_max_len)
 132                 minStrLen = hex_max_len;
 133         for(; i < minStrLen; i++, tmp += 1)
 134                 sprintf(tmp, " ");
 135
 136         return;
 137 }
 138
 139 // printing and converting functions
 140
 141 void print_hex(const uint8_t * data, const size_t len)
 142 {
 143         size_t i;
 144
 145         for (i=0; i < len; i++)
 146                 printf("%02x ", data[i]);
 147
 148         printf("\n");
 149 }
 150
 151 void print_hex_break(const uint8_t *data, const size_t len, uint8_t breaks) {
 152
 153         int rownum = 0;
 154         printf("[%02d] | ", rownum);
 155         for (int i = 0; i < len; ++i) {
 156
 157                 printf("%02X ", data[i]);
 158
 159                 // check if a line break is needed
 160                 if ( breaks > 0 && !((i+1) % breaks) && (i+1 < len) ) {
 161                         ++rownum;
 162                         printf("\n[%02d] | ", rownum);
 163                 }
 164         }
 165         printf("\n");
 166 }
 167
 168 char *sprint_hex(const uint8_t *data, const size_t len) {
 169         static char buf[1025] = {0};
 170
 171         hex_to_buffer((uint8_t *)buf, data, len, sizeof(buf) - 1, 0, 1, false);
 172
 173         return buf;
 174 }
 175
 176 char *sprint_hex_inrow_ex(const uint8_t *data, const size_t len, const size_t min_str_len) {
 177         static char buf[1025] = {0};
 178
 179         hex_to_buffer((uint8_t *)buf, data, len, sizeof(buf) - 1, min_str_len, 0, false);
 180
 181         return buf;
 182 }
 183
 184 char *sprint_hex_inrow(const uint8_t *data, const size_t len) {
 185         return sprint_hex_inrow_ex(data, len, 0);
 186 }
 187
 188 char *sprint_bin_break(const uint8_t *data, const size_t len, const uint8_t breaks) {
 189         // make sure we don't go beyond our char array memory
 190         int max_len;
 191         if (breaks==0)
 192                 max_len = ( len > MAX_BIN_BREAK_LENGTH ) ? MAX_BIN_BREAK_LENGTH : len;
 193         else
 194                 max_len = ( len+(len/breaks) > MAX_BIN_BREAK_LENGTH ) ? MAX_BIN_BREAK_LENGTH : len+(len/breaks);
 195
 196         static char buf[MAX_BIN_BREAK_LENGTH]; // 3072 + end of line characters if broken at 8 bits
 197         //clear memory
 198         memset(buf, 0x00, sizeof(buf));
 199         char *tmp = buf;
 200
 201         size_t in_index = 0;
 202         // loop through the out_index to make sure we don't go too far
 203         for (size_t out_index=0; out_index < max_len; out_index++) {
 204                 // set character - (should be binary but verify it isn't more than 1 digit)
 205                 if (data[in_index]<10)
 206                         sprintf(tmp++, "%u", (unsigned int) data[in_index]);
 207                 // check if a line break is needed and we have room to print it in our array
 208                 if ( (breaks > 0) && !((in_index+1) % breaks) && (out_index+1 < max_len) ) {
 209                         // increment and print line break
 210                         out_index++;
 211                         sprintf(tmp++, "%s","\n");
 212                 }
 213                 in_index++;
 214         }
 215
 216         return buf;
 217 }
 218
 219 char *sprint_bin(const uint8_t *data, const size_t len) {
 220         return sprint_bin_break(data, len, 0);
 221 }
 222
 223 char *sprint_hex_ascii(const uint8_t *data, const size_t len) {
 224         static char buf[1024];
 225         char *tmp = buf;
 226         memset(buf, 0x00, 1024);
 227         size_t max_len = (len > 255) ? 255 : len;
 228         // max 255 bytes * 3 + 2 characters = 767 in buffer
 229         sprintf(tmp, "%s| ", sprint_hex(data, max_len) );
 230
 231         size_t i = 0;
 232         size_t pos = (max_len * 3)+2;
 233         // add another 255 characters ascii = 1020 characters of buffer used
 234         while(i < max_len) {
 235                 char c = data[i];
 236                 if ( (c < 32) || (c == 127))
 237                         c = '.';
 238                 sprintf(tmp+pos+i, "%c",  c);
 239                 ++i;
 240         }
 241         return buf;
 242 }
 243
 244 char *sprint_ascii_ex(const uint8_t *data, const size_t len, const size_t min_str_len) {
 245         static char buf[1024];
 246         char *tmp = buf;
 247         memset(buf, 0x00, 1024);
 248         size_t max_len = (len > 1010) ? 1010 : len;
 249         size_t i = 0;
 250         while(i < max_len){
 251                 char c = data[i];
 252                 tmp[i] = ((c < 32) || (c == 127)) ? '.' : c;
 253                 ++i;
 254         }
 255
 256         int minStrLen = min_str_len > i ? min_str_len : 0;
 257         for(; i < minStrLen; ++i)
 258                 tmp[i] = ' ';
 259
 260         return buf;
 261 }
 262
 263 char *sprint_ascii(const uint8_t *data, const size_t len) {
 264         return sprint_ascii_ex(data, len, 0);
 265 }
 266
 267 void num_to_bytes(uint64_t n, size_t len, uint8_t* dest)
 268 {
 269         while (len--) {
 270                 dest[len] = (uint8_t) n;
 271                 n >>= 8;
 272         }
 273 }
 274
 275 uint64_t bytes_to_num(uint8_t* src, size_t len)
 276 {
 277         uint64_t num = 0;
 278         while (len--)
 279         {
 280                 num = (num << 8) | (*src);
 281                 src++;
 282         }
 283         return num;
 284 }
 285
 286 void num_to_bytebits(uint64_t   n, size_t len, uint8_t *dest) {
 287         while (len--) {
 288                 dest[len] = n & 1;
 289                 n >>= 1;
 290         }
 291 }
 292
 293 //least significant bit first
 294 void num_to_bytebitsLSBF(uint64_t n, size_t len, uint8_t *dest) {
 295         for(int i = 0 ; i < len ; ++i) {
 296                 dest[i] =  n & 1;
 297                 n >>= 1;
 298         }
 299 }
 300
 301 // Swap bit order on a uint32_t value.  Can be limited by nrbits just use say 8bits reversal
 302 // And clears the rest of the bits.
 303 uint32_t SwapBits(uint32_t value, int nrbits) {
 304         uint32_t newvalue = 0;
 305         for(int i = 0; i < nrbits; i++) {
 306                 newvalue ^= ((value >> i) & 1) << (nrbits - 1 - i);
 307         }
 308         return newvalue;
 309 }
 310
 311 // aa,bb,cc,dd,ee,ff,gg,hh, ii,jj,kk,ll,mm,nn,oo,pp
 312 // to
 313 // hh,gg,ff,ee,dd,cc,bb,aa, pp,oo,nn,mm,ll,kk,jj,ii
 314 // up to 64 bytes or 512 bits
 315 uint8_t *SwapEndian64(const uint8_t *src, const size_t len, const uint8_t blockSize){
 316         static uint8_t buf[64];
 317         memset(buf, 0x00, 64);
 318         uint8_t *tmp = buf;
 319         for (uint8_t block=0; block < (uint8_t)(len/blockSize); block++){
 320                 for (size_t i = 0; i < blockSize; i++){
 321                         tmp[i+(blockSize*block)] = src[(blockSize-1-i)+(blockSize*block)];
 322                 }
 323         }
 324         return tmp;
 325 }
 326
 327 // takes a uint8_t src array, for len items and reverses the byte order in blocksizes (8,16,32,64),
 328 // returns: the dest array contains the reordered src array.
 329 void SwapEndian64ex(const uint8_t *src, const size_t len, const uint8_t blockSize, uint8_t *dest){
 330         for (uint8_t block=0; block < (uint8_t)(len/blockSize); block++){
 331                 for (size_t i = 0; i < blockSize; i++){
 332                         dest[i+(blockSize*block)] = src[(blockSize-1-i)+(blockSize*block)];
 333                 }
 334         }
 335 }
 336
 337 //assumes little endian
 338 char * printBits(size_t const size, void const * const ptr)
 339 {
 340     unsigned char *b = (unsigned char*) ptr;
 341     unsigned char byte;
 342         static char buf[1024];
 343         char * tmp = buf;
 344     int i, j;
 345
 346     for (i=size-1;i>=0;i--)
 347     {
 348         for (j=7;j>=0;j--)
 349         {
 350             byte = b[i] & (1<<j);
 351             byte >>= j;
 352             sprintf(tmp, "%u", (unsigned int)byte);
 353                         tmp++;
 354         }
 355     }
 356         return buf;
 357 }
 358
 359 //  -------------------------------------------------------------------------
 360 //  string parameters lib
 361 //  -------------------------------------------------------------------------
 362
 363 //  -------------------------------------------------------------------------
 364 //  line     - param line
 365 //  bg, en   - symbol numbers in param line of beginning and ending parameter
 366 //  paramnum - param number (from 0)
 367 //  -------------------------------------------------------------------------
 368 int param_getptr(const char *line, int *bg, int *en, int paramnum)
 369 {
 370         int i;
 371         int len = strlen(line);
 372
 373         *bg = 0;
 374         *en = 0;
 375
 376   // skip spaces
 377         while (line[*bg] ==' ' || line[*bg]=='\t') (*bg)++;
 378         if (*bg >= len) {
 379                 return 1;
 380         }
 381
 382         for (i = 0; i < paramnum; i++) {
 383                 while (line[*bg]!=' ' && line[*bg]!='\t' && line[*bg] != '\0') (*bg)++;
 384                 while (line[*bg]==' ' || line[*bg]=='\t') (*bg)++;
 385
 386                 if (line[*bg] == '\0') return 1;
 387         }
 388
 389         *en = *bg;
 390         while (line[*en] != ' ' && line[*en] != '\t' && line[*en] != '\0') (*en)++;
 391
 392         (*en)--;
 393
 394         return 0;
 395 }
 396
 397
 398 int param_getlength(const char *line, int paramnum)
 399 {
 400         int bg, en;
 401
 402         if (param_getptr(line, &bg, &en, paramnum)) return 0;
 403
 404         return en - bg + 1;
 405 }
 406
 407 char param_getchar(const char *line, int paramnum) {
 408         return param_getchar_indx(line, 0, paramnum);
 409 }
 410
 411 char param_getchar_indx(const char *line, int indx, int paramnum) {
 412         int bg, en;
 413
 414         if (param_getptr(line, &bg, &en, paramnum)) return 0x00;
 415
 416         if (bg + indx > en)
 417                 return '\0';
 418
 419         return line[bg + indx];
 420 }
 421
 422 uint8_t param_get8(const char *line, int paramnum)
 423 {
 424         return param_get8ex(line, paramnum, 0, 10);
 425 }
 426
 427 /**
 428  * @brief Reads a decimal integer (actually, 0-254, not 255)
 429  * @param line
 430  * @param paramnum
 431  * @return -1 if error
 432  */
 433 uint8_t param_getdec(const char *line, int paramnum, uint8_t *destination)
 434 {
 435         uint8_t val =  param_get8ex(line, paramnum, 255, 10);
 436         if( (int8_t) val == -1) return 1;
 437         (*destination) = val;
 438         return 0;
 439 }
 440 /**
 441  * @brief Checks if param is decimal
 442  * @param line
 443  * @param paramnum
 444  * @return
 445  */
 446 uint8_t param_isdec(const char *line, int paramnum)
 447 {
 448         int bg, en;
 449         //TODO, check more thorougly
 450         if (!param_getptr(line, &bg, &en, paramnum)) return 1;
 451                 //              return strtoul(&line[bg], NULL, 10) & 0xff;
 452
 453         return 0;
 454 }
 455
 456 uint8_t param_get8ex(const char *line, int paramnum, int deflt, int base)
 457 {
 458         int bg, en;
 459
 460         if (!param_getptr(line, &bg, &en, paramnum))
 461                 return strtoul(&line[bg], NULL, base) & 0xff;
 462         else
 463                 return deflt;
 464 }
 465
 466 uint32_t param_get32ex(const char *line, int paramnum, int deflt, int base)
 467 {
 468         int bg, en;
 469
 470         if (!param_getptr(line, &bg, &en, paramnum))
 471                 return strtoul(&line[bg], NULL, base);
 472         else
 473                 return deflt;
 474 }
 475
 476 uint64_t param_get64ex(const char *line, int paramnum, int deflt, int base)
 477 {
 478         int bg, en;
 479
 480         if (!param_getptr(line, &bg, &en, paramnum))
 481                 return strtoull(&line[bg], NULL, base);
 482         else
 483                 return deflt;
 484 }
 485
 486 int param_gethex(const char *line, int paramnum, uint8_t * data, int hexcnt)
 487 {
 488         int bg, en, temp, i;
 489
 490         if (hexcnt % 2)
 491                 return 1;
 492
 493         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 494
 495         if (en - bg + 1 != hexcnt)
 496                 return 1;
 497
 498         for(i = 0; i < hexcnt; i += 2) {
 499                 if (!(isxdigit((unsigned char)line[bg + i]) && isxdigit((unsigned char)line[bg + i + 1])) )     return 1;
 500
 501                 sscanf((char[]){line[bg + i], line[bg + i + 1], 0}, "%X", &temp);
 502                 data[i / 2] = temp & 0xff;
 503         }
 504
 505         return 0;
 506 }
 507 int param_gethex_ex(const char *line, int paramnum, uint8_t * data, int *hexcnt)
 508 {
 509         int bg, en, temp, i;
 510
 511         //if (hexcnt % 2)
 512         //      return 1;
 513
 514         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 515
 516         *hexcnt = en - bg + 1;
 517         if (*hexcnt % 2) //error if not complete hex bytes
 518                 return 1;
 519
 520         for(i = 0; i < *hexcnt; i += 2) {
 521                 if (!(isxdigit((unsigned char)line[bg + i]) && isxdigit((unsigned char)line[bg + i + 1])) )     return 1;
 522
 523                 sscanf((char[]){line[bg + i], line[bg + i + 1], 0}, "%X", &temp);
 524                 data[i / 2] = temp & 0xff;
 525         }
 526
 527         return 0;
 528 }
 529
 530 int param_gethex_to_eol(const char *line, int paramnum, uint8_t * data, int maxdatalen, int *datalen) {
 531         int bg, en;
 532         uint32_t temp;
 533         char buf[5] = {0};
 534
 535         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 536
 537         *datalen = 0;
 538
 539         int indx = bg;
 540         while (line[indx]) {
 541                 if (line[indx] == '\t' || line[indx] == ' ') {
 542                         indx++;
 543                         continue;
 544                 }
 545
 546                 if (isxdigit((unsigned char)line[indx])) {
 547                         buf[strlen(buf) + 1] = 0x00;
 548                         buf[strlen(buf)] = line[indx];
 549                 } else {
 550                         // if we have symbols other than spaces and hex
 551                         return 1;
 552                 }
 553
 554                 if (*datalen >= maxdatalen) {
 555                         // if we dont have space in buffer and have symbols to translate
 556                         return 2;
 557                 }
 558
 559                 if (strlen(buf) >= 2) {
 560                         sscanf(buf, "%x", &temp);
 561                         data[*datalen] = (uint8_t)(temp & 0xff);
 562                         *buf = 0;
 563                         (*datalen)++;
 564                 }
 565
 566                 indx++;
 567         }
 568
 569         if (strlen(buf) > 0)
 570                 //error when not completed hex bytes
 571                 return 3;
 572
 573         return 0;
 574 }
 575
 576 int param_getstr(const char *line, int paramnum, char * str, size_t buffersize)
 577 {
 578         int bg, en;
 579
 580         if (param_getptr(line, &bg, &en, paramnum)) {
 581                 return 0;
 582         }
 583
 584         // Prevent out of bounds errors
 585         if (en - bg + 1 >= buffersize) {
 586                 printf("out of bounds error: want %d bytes have %zd bytes\n", en - bg + 1 + 1, buffersize);
 587                 return 0;
 588         }
 589
 590         memcpy(str, line + bg, en - bg + 1);
 591         str[en - bg + 1] = 0;
 592
 593         return en - bg + 1;
 594 }
 595
 596 /*
 597 The following methods comes from Rfidler sourcecode.
 598 https://github.com/ApertureLabsLtd/RFIDler/blob/master/firmware/Pic32/RFIDler.X/src/
 599 */
 600
 601 // convert hex to sequence of 0/1 bit values
 602 // returns number of bits converted
 603 int hextobinarray(char *target, char *source)
 604 {
 605     int length, i, count= 0;
 606     char* start = source;
 607     char x;
 608
 609     length = strlen(source);
 610     // process 4 bits (1 hex digit) at a time
 611     while(length--)
 612     {
 613         x= *(source++);
 614         // capitalize
 615         if (x >= 'a' && x <= 'f')
 616             x -= 32;
 617         // convert to numeric value
 618         if (x >= '0' && x <= '9')
 619             x -= '0';
 620         else if (x >= 'A' && x <= 'F')
 621             x -= 'A' - 10;
 622         else {
 623                 printf("Discovered unknown character %c %d at idx %tu of %s\n", x, x, source - start, start);
 624             return 0;
 625         }
 626         // output
 627         for(i= 0 ; i < 4 ; ++i, ++count)
 628             *(target++)= (x >> (3 - i)) & 1;
 629     }
 630
 631     return count;
 632 }
 633
 634 // convert hex to human readable binary string
 635 int hextobinstring(char *target, char *source)
 636 {
 637     int length;
 638
 639     if(!(length= hextobinarray(target, source)))
 640         return 0;
 641     binarraytobinstring(target, target, length);
 642     return length;
 643 }
 644
 645 // convert binary array of 0x00/0x01 values to hex (safe to do in place as target will always be shorter than source)
 646 // return number of bits converted
 647 int binarraytohex(char *target,char *source, int length)
 648 {
 649     unsigned char i, x;
 650     int j = length;
 651
 652     if(j % 4)
 653         return 0;
 654
 655     while(j)
 656     {
 657         for(i= x= 0 ; i < 4 ; ++i)
 658             x +=  ( source[i] << (3 - i));
 659         sprintf(target,"%X", (unsigned int)x);
 660         ++target;
 661         source += 4;
 662         j -= 4;
 663     }
 664     return length;
 665 }
 666
 667 // convert binary array to human readable binary
 668 void binarraytobinstring(char *target, char *source,  int length)
 669 {
 670     int i;
 671
 672     for(i= 0 ; i < length ; ++i)
 673         *(target++)= *(source++) + '0';
 674     *target= '\0';
 675 }
 676
 677 // return parity bit required to match type
 678 uint8_t GetParity( uint8_t *bits, uint8_t type, int length)
 679 {
 680     int x;
 681
 682     for(x= 0 ; length > 0 ; --length)
 683         x += bits[length - 1];
 684     x %= 2;
 685
 686     return x ^ type;
 687 }
 688
 689 // add HID parity to binary array: EVEN prefix for 1st half of ID, ODD suffix for 2nd half
 690 void wiegand_add_parity(uint8_t *target, uint8_t *source, uint8_t length)
 691 {
 692     *(target++)= GetParity(source, EVEN, length / 2);
 693     memcpy(target, source, length);
 694     target += length;
 695     *(target)= GetParity(source + length / 2, ODD, length / 2);
 696 }
 697
 698 // xor two arrays together for len items.  The dst array contains the new xored values.
 699 void xor(unsigned char *dst, unsigned char *src, size_t len) {
 700    for( ; len > 0; len--,dst++,src++)
 701        *dst ^= *src;
 702 }
 703
 704 int32_t le24toh (uint8_t data[3]) {
 705     return (data[2] << 16) | (data[1] << 8) | data[0];
 706 }
 707 uint32_t le32toh (uint8_t *data) {
 708         return (uint32_t)( (data[3]<<24) | (data[2]<<16) | (data[1]<<8) | data[0]);
 709 }
 710
 711 // RotateLeft - Ultralight, Desfire, works on byte level
 712 // 00-01-02  >> 01-02-00
 713 void rol(uint8_t *data, const size_t len){
 714     uint8_t first = data[0];
 715     for (size_t i = 0; i < len-1; i++) {
 716         data[i] = data[i+1];
 717     }
 718     data[len-1] = first;
 719 }
 720
 721
 722 // Replace unprintable characters with a dot in char buffer
 723 void clean_ascii(unsigned char *buf, size_t len) {
 724   for (size_t i = 0; i < len; i++) {
 725     if (!isprint(buf[i]))
 726       buf[i] = '.';
 727   }
 728 }
 729
 730 // replace \r \n to \0
 731 void strcleanrn(char *buf, size_t len) {
 732         strcreplace(buf, len, '\n', '\0');
 733         strcreplace(buf, len, '\r', '\0');
 734 }
 735
 736 // replace char in buffer
 737 void strcreplace(char *buf, size_t len, char from, char to) {
 738   for (size_t i = 0; i < len; i++) {
 739     if (buf[i] == from)
 740       buf[i] = to;
 741   }
 742 }
 743
 744 char *strmcopy(char *buf) {
 745         char * str = NULL;
 746         if ((str = (char*) malloc(strlen(buf) + 1)) != NULL) {
 747                 memset(str, 0, strlen(buf) + 1);
 748                 strcpy(str, buf);
 749         }
 750         return str;
 751 }
 752
 753
 754 // determine number of logical CPU cores (use for multithreaded functions)
 755 extern int num_CPUs(void)
 756 {
 757 #if defined(_WIN32)
 758         #include <sysinfoapi.h>
 759         SYSTEM_INFO sysinfo;
 760         GetSystemInfo(&sysinfo);
 761         return sysinfo.dwNumberOfProcessors;
 762 #elif defined(__linux__) || defined(__APPLE__)
 763         #include <unistd.h>
 764         return sysconf(_SC_NPROCESSORS_ONLN);
 765 #else
 766         return 1;
 767 #endif
 768 }
 769