src/helper/binarybuffer.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2
   3 /***************************************************************************
   4  *   Copyright (C) 2004, 2005 by Dominic Rath                              *
   5  *   Dominic.Rath@gmx.de                                                   *
   6  *                                                                         *
   7  *   Copyright (C) 2007,2008 Øyvind Harboe                                 *
   8  *   oyvind.harboe@zylin.com                                               *
   9  ***************************************************************************/
  10
  11 #ifdef HAVE_CONFIG_H
  12 #include "config.h"
  13 #endif
  14
  15 #include "helper/replacements.h"
  16 #include "log.h"
  17 #include "binarybuffer.h"
  18
  19 static const unsigned char bit_reverse_table256[] = {
  20         0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, 0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
  21         0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8, 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8,
  22         0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4, 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
  23         0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, 0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC,
  24         0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2, 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2,
  25         0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA, 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
  26         0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6, 0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6,
  27         0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE, 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE,
  28         0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1, 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
  29         0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, 0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9,
  30         0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5, 0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5,
  31         0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED, 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
  32         0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3, 0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
  33         0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB, 0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB,
  34         0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7, 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
  35         0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
  36 };
  37
  38 static const char hex_digits[] = {
  39         '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
  40         'a', 'b', 'c', 'd', 'e', 'f'
  41 };
  42
  43 void *buf_cpy(const void *from, void *_to, unsigned size)
  44 {
  45         if (!from || !_to)
  46                 return NULL;
  47
  48         /* copy entire buffer */
  49         memcpy(_to, from, DIV_ROUND_UP(size, 8));
  50
  51         /* mask out bits that don't belong to the buffer */
  52         unsigned trailing_bits = size % 8;
  53         if (trailing_bits) {
  54                 uint8_t *to = _to;
  55                 to[size / 8] &= (1 << trailing_bits) - 1;
  56         }
  57         return _to;
  58 }
  59
  60 static bool buf_cmp_masked(uint8_t a, uint8_t b, uint8_t m)
  61 {
  62         return (a & m) != (b & m);
  63 }
  64 static bool buf_cmp_trailing(uint8_t a, uint8_t b, uint8_t m, unsigned trailing)
  65 {
  66         uint8_t mask = (1 << trailing) - 1;
  67         return buf_cmp_masked(a, b, mask & m);
  68 }
  69
  70 bool buf_cmp(const void *_buf1, const void *_buf2, unsigned size)
  71 {
  72         if (!_buf1 || !_buf2)
  73                 return _buf1 != _buf2;
  74
  75         unsigned last = size / 8;
  76         if (memcmp(_buf1, _buf2, last) != 0)
  77                 return false;
  78
  79         unsigned trailing = size % 8;
  80         if (!trailing)
  81                 return false;
  82
  83         const uint8_t *buf1 = _buf1, *buf2 = _buf2;
  84         return buf_cmp_trailing(buf1[last], buf2[last], 0xff, trailing);
  85 }
  86
  87 bool buf_cmp_mask(const void *_buf1, const void *_buf2,
  88         const void *_mask, unsigned size)
  89 {
  90         if (!_buf1 || !_buf2)
  91                 return _buf1 != _buf2 || _buf1 != _mask;
  92
  93         const uint8_t *buf1 = _buf1, *buf2 = _buf2, *mask = _mask;
  94         unsigned last = size / 8;
  95         for (unsigned i = 0; i < last; i++) {
  96                 if (buf_cmp_masked(buf1[i], buf2[i], mask[i]))
  97                         return true;
  98         }
  99         unsigned trailing = size % 8;
 100         if (!trailing)
 101                 return false;
 102         return buf_cmp_trailing(buf1[last], buf2[last], mask[last], trailing);
 103 }
 104
 105 void *buf_set_ones(void *_buf, unsigned size)
 106 {
 107         uint8_t *buf = _buf;
 108         if (!buf)
 109                 return NULL;
 110
 111         memset(buf, 0xff, size / 8);
 112
 113         unsigned trailing_bits = size % 8;
 114         if (trailing_bits)
 115                 buf[size / 8] = (1 << trailing_bits) - 1;
 116
 117         return buf;
 118 }
 119
 120 void *buf_set_buf(const void *_src, unsigned src_start,
 121         void *_dst, unsigned dst_start, unsigned len)
 122 {
 123         const uint8_t *src = _src;
 124         uint8_t *dst = _dst;
 125         unsigned i, sb, db, sq, dq, lb, lq;
 126
 127         sb = src_start / 8;
 128         db = dst_start / 8;
 129         sq = src_start % 8;
 130         dq = dst_start % 8;
 131         lb = len / 8;
 132         lq = len % 8;
 133
 134         src += sb;
 135         dst += db;
 136
 137         /* check if both buffers are on byte boundary and
 138          * len is a multiple of 8bit so we can simple copy
 139          * the buffer */
 140         if ((sq == 0) && (dq == 0) &&  (lq == 0)) {
 141                 for (i = 0; i < lb; i++)
 142                         *dst++ = *src++;
 143                 return _dst;
 144         }
 145
 146         /* fallback to slow bit copy */
 147         for (i = 0; i < len; i++) {
 148                 if (((*src >> (sq&7)) & 1) == 1)
 149                         *dst |= 1 << (dq&7);
 150                 else
 151                         *dst &= ~(1 << (dq&7));
 152                 if (sq++ == 7) {
 153                         sq = 0;
 154                         src++;
 155                 }
 156                 if (dq++ == 7) {
 157                         dq = 0;
 158                         dst++;
 159                 }
 160         }
 161
 162         return _dst;
 163 }
 164
 165 uint32_t flip_u32(uint32_t value, unsigned int num)
 166 {
 167         uint32_t c = (bit_reverse_table256[value & 0xff] << 24) |
 168                 (bit_reverse_table256[(value >> 8) & 0xff] << 16) |
 169                 (bit_reverse_table256[(value >> 16) & 0xff] << 8) |
 170                 (bit_reverse_table256[(value >> 24) & 0xff]);
 171
 172         if (num < 32)
 173                 c = c >> (32 - num);
 174
 175         return c;
 176 }
 177
 178 char *buf_to_hex_str(const void *_buf, unsigned buf_len)
 179 {
 180         unsigned len_bytes = DIV_ROUND_UP(buf_len, 8);
 181         char *str = calloc(len_bytes * 2 + 1, 1);
 182
 183         const uint8_t *buf = _buf;
 184         for (unsigned i = 0; i < len_bytes; i++) {
 185                 uint8_t tmp = buf[len_bytes - i - 1];
 186                 if ((i == 0) && (buf_len % 8))
 187                         tmp &= (0xff >> (8 - (buf_len % 8)));
 188                 str[2 * i] = hex_digits[tmp >> 4];
 189                 str[2 * i + 1] = hex_digits[tmp & 0xf];
 190         }
 191
 192         return str;
 193 }
 194
 195 static bool str_has_hex_prefix(const char *s)
 196 {
 197         /* Starts with "0x" or "0X" */
 198         return (s[0] == '0') && (s[1] == 'x' || s[1] == 'X');
 199 }
 200
 201 static bool str_has_octal_prefix(const char *s)
 202 {
 203         /* - starts with '0',
 204          * - has at least two characters, and
 205          * - the second character is not 'x' or 'X' */
 206         return (s[0] == '0') && (s[1] != '\0') && (s[1] != 'x') && (s[1] != 'X');
 207 }
 208
 209 /**
 210  * Try to identify the radix of the number by looking at its prefix.
 211  * No further validation of the number is preformed.
 212  */
 213 static unsigned int str_radix_guess(const char *str)
 214 {
 215         if (str_has_hex_prefix(str))
 216                 return 16;
 217
 218         if (str_has_octal_prefix(str))
 219                 return 8;
 220
 221         /* Otherwise assume a decimal number. */
 222         return 10;
 223 }
 224
 225 /** Strip leading "0x" or "0X" from hex numbers or "0" from octal numbers. */
 226 static const char *str_strip_number_prefix(const char *str, unsigned int radix)
 227 {
 228         switch (radix) {
 229         case 16:
 230                 return str + 2;
 231         case 8:
 232                 return str + 1;
 233         case 10:
 234         default:
 235                 return str;
 236         }
 237 }
 238
 239 int str_to_buf(const char *str, void *_buf, unsigned int buf_bitsize)
 240 {
 241         assert(str);
 242         assert(_buf);
 243         assert(buf_bitsize > 0);
 244
 245         uint8_t *buf = _buf;
 246         unsigned int radix = str_radix_guess(str);
 247
 248         str = str_strip_number_prefix(str, radix);
 249
 250         const size_t str_len = strlen(str);
 251         if (str_len == 0)
 252                 return ERROR_INVALID_NUMBER;
 253
 254         const size_t buf_len = DIV_ROUND_UP(buf_bitsize, 8);
 255         memset(buf, 0, buf_len);
 256
 257         /* Go through the zero-terminated buffer
 258          * of input digits (ASCII) */
 259         for (; *str; str++) {
 260                 unsigned int tmp;
 261                 const char c = *str;
 262
 263                 if ((c >= '0') && (c <= '9')) {
 264                         tmp = c - '0';
 265                 } else if ((c >= 'a') && (c <= 'f')) {
 266                         tmp = c - 'a' + 10;
 267                 } else if ((c >= 'A') && (c <= 'F')) {
 268                         tmp = c - 'A' + 10;
 269                 } else {
 270                         /* Characters other than [0-9,a-f,A-F] are invalid */
 271                         return ERROR_INVALID_NUMBER;
 272                 }
 273
 274                 /* Error on invalid digit for current radix */
 275                 if (tmp >= radix)
 276                         return ERROR_INVALID_NUMBER;
 277
 278                 /* Add the current digit (tmp) to the intermediate result in buf */
 279                 for (unsigned int j = 0; j < buf_len; j++) {
 280                         tmp += buf[j] * radix;
 281                         buf[j] = tmp & 0xFFu;
 282                         tmp >>= 8;
 283                 }
 284
 285                 /* buf should be large enough to contain the whole result. */
 286                 if (tmp != 0)
 287                         return ERROR_NUMBER_EXCEEDS_BUFFER;
 288         }
 289
 290         /* Check the partial most significant byte */
 291         if (buf_bitsize % 8) {
 292                 const uint8_t mask = 0xFFu << (buf_bitsize % 8);
 293                 if ((buf[buf_len - 1] & mask) != 0x0)
 294                         return ERROR_NUMBER_EXCEEDS_BUFFER;
 295         }
 296
 297         return ERROR_OK;
 298 }
 299
 300 void bit_copy_queue_init(struct bit_copy_queue *q)
 301 {
 302         INIT_LIST_HEAD(&q->list);
 303 }
 304
 305 int bit_copy_queued(struct bit_copy_queue *q, uint8_t *dst, unsigned dst_offset, const uint8_t *src,
 306         unsigned src_offset, unsigned bit_count)
 307 {
 308         struct bit_copy_queue_entry *qe = malloc(sizeof(*qe));
 309         if (!qe)
 310                 return ERROR_FAIL;
 311
 312         qe->dst = dst;
 313         qe->dst_offset = dst_offset;
 314         qe->src = src;
 315         qe->src_offset = src_offset;
 316         qe->bit_count = bit_count;
 317         list_add_tail(&qe->list, &q->list);
 318
 319         return ERROR_OK;
 320 }
 321
 322 void bit_copy_execute(struct bit_copy_queue *q)
 323 {
 324         struct bit_copy_queue_entry *qe;
 325         struct bit_copy_queue_entry *tmp;
 326         list_for_each_entry_safe(qe, tmp, &q->list, list) {
 327                 bit_copy(qe->dst, qe->dst_offset, qe->src, qe->src_offset, qe->bit_count);
 328                 list_del(&qe->list);
 329                 free(qe);
 330         }
 331 }
 332
 333 void bit_copy_discard(struct bit_copy_queue *q)
 334 {
 335         struct bit_copy_queue_entry *qe;
 336         struct bit_copy_queue_entry *tmp;
 337         list_for_each_entry_safe(qe, tmp, &q->list, list) {
 338                 list_del(&qe->list);
 339                 free(qe);
 340         }
 341 }
 342
 343 /**
 344  * Convert a string of hexadecimal pairs into its binary
 345  * representation.
 346  *
 347  * @param[out] bin Buffer to store binary representation. The buffer size must
 348  *                 be at least @p count.
 349  * @param[in] hex String with hexadecimal pairs to convert into its binary
 350  *                representation.
 351  * @param[in] count Number of hexadecimal pairs to convert.
 352  *
 353  * @return The number of converted hexadecimal pairs.
 354  */
 355 size_t unhexify(uint8_t *bin, const char *hex, size_t count)
 356 {
 357         size_t i;
 358         char tmp;
 359
 360         if (!bin || !hex)
 361                 return 0;
 362
 363         memset(bin, 0, count);
 364
 365         for (i = 0; i < 2 * count; i++) {
 366                 if (hex[i] >= 'a' && hex[i] <= 'f')
 367                         tmp = hex[i] - 'a' + 10;
 368                 else if (hex[i] >= 'A' && hex[i] <= 'F')
 369                         tmp = hex[i] - 'A' + 10;
 370                 else if (hex[i] >= '0' && hex[i] <= '9')
 371                         tmp = hex[i] - '0';
 372                 else
 373                         return i / 2;
 374
 375                 bin[i / 2] |= tmp << (4 * ((i + 1) % 2));
 376         }
 377
 378         return i / 2;
 379 }
 380
 381 /**
 382  * Convert binary data into a string of hexadecimal pairs.
 383  *
 384  * @param[out] hex Buffer to store string of hexadecimal pairs. The buffer size
 385  *                 must be at least @p length.
 386  * @param[in] bin Buffer with binary data to convert into hexadecimal pairs.
 387  * @param[in] count Number of bytes to convert.
 388  * @param[in] length Maximum number of characters, including null-terminator,
 389  *                   to store into @p hex.
 390  *
 391  * @returns The length of the converted string excluding null-terminator.
 392  */
 393 size_t hexify(char *hex, const uint8_t *bin, size_t count, size_t length)
 394 {
 395         size_t i;
 396         uint8_t tmp;
 397
 398         if (!length)
 399                 return 0;
 400
 401         for (i = 0; i < length - 1 && i < 2 * count; i++) {
 402                 tmp = (bin[i / 2] >> (4 * ((i + 1) % 2))) & 0x0f;
 403                 hex[i] = hex_digits[tmp];
 404         }
 405
 406         hex[i] = 0;
 407
 408         return i;
 409 }
 410
 411 void buffer_shr(void *_buf, unsigned buf_len, unsigned count)
 412 {
 413         unsigned i;
 414         unsigned char *buf = _buf;
 415         unsigned bytes_to_remove;
 416         unsigned shift;
 417
 418         bytes_to_remove = count / 8;
 419         shift = count - (bytes_to_remove * 8);
 420
 421         for (i = 0; i < (buf_len - 1); i++)
 422                 buf[i] = (buf[i] >> shift) | ((buf[i+1] << (8 - shift)) & 0xff);
 423
 424         buf[(buf_len - 1)] = buf[(buf_len - 1)] >> shift;
 425
 426         if (bytes_to_remove) {
 427                 memmove(buf, &buf[bytes_to_remove], buf_len - bytes_to_remove);
 428                 memset(&buf[buf_len - bytes_to_remove], 0, bytes_to_remove);
 429         }
 430 }