1 /* $OpenBSD: bytestring.h,v 1.3 2022/01/06 14:32:55 jsing Exp $ */ 2 /* 3 * Copyright (c) 2014, Google Inc. 4 * 5 * Permission to use, copy, modify, and/or distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 12 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION 14 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 15 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #ifndef OPENSSL_HEADER_BYTESTRING_H 19 #define OPENSSL_HEADER_BYTESTRING_H 20 21 #include <sys/types.h> 22 #include <stdint.h> 23 24 __BEGIN_HIDDEN_DECLS 25 26 /* 27 * Bytestrings are used for parsing and building TLS and ASN.1 messages. 28 * 29 * A "CBS" (CRYPTO ByteString) represents a string of bytes in memory and 30 * provides utility functions for safely parsing length-prefixed structures 31 * like TLS and ASN.1 from it. 32 * 33 * A "CBB" (CRYPTO ByteBuilder) is a memory buffer that grows as needed and 34 * provides utility functions for building length-prefixed messages. 35 */ 36 37 /* CRYPTO ByteString */ 38 typedef struct cbs_st { 39 const uint8_t *data; 40 size_t initial_len; 41 size_t len; 42 } CBS; 43 44 /* 45 * CBS_init sets |cbs| to point to |data|. It does not take ownership of 46 * |data|. 47 */ 48 void CBS_init(CBS *cbs, const uint8_t *data, size_t len); 49 50 /* 51 * CBS_skip advances |cbs| by |len| bytes. It returns one on success and zero 52 * otherwise. 53 */ 54 int CBS_skip(CBS *cbs, size_t len); 55 56 /* 57 * CBS_data returns a pointer to the contents of |cbs|. 58 */ 59 const uint8_t *CBS_data(const CBS *cbs); 60 61 /* 62 * CBS_len returns the number of bytes remaining in |cbs|. 63 */ 64 size_t CBS_len(const CBS *cbs); 65 66 /* 67 * CBS_offset returns the current offset into the original data of |cbs|. 68 */ 69 size_t CBS_offset(const CBS *cbs); 70 71 /* 72 * CBS_stow copies the current contents of |cbs| into |*out_ptr| and 73 * |*out_len|. If |*out_ptr| is not NULL, the contents are freed with 74 * free. It returns one on success and zero on allocation failure. On 75 * success, |*out_ptr| should be freed with free. If |cbs| is empty, 76 * |*out_ptr| will be NULL. 77 */ 78 int CBS_stow(const CBS *cbs, uint8_t **out_ptr, size_t *out_len); 79 80 /* 81 * CBS_strdup copies the current contents of |cbs| into |*out_ptr| as a 82 * NUL-terminated C string. If |*out_ptr| is not NULL, the contents are freed 83 * with free. It returns one on success and zero on allocation 84 * failure. On success, |*out_ptr| should be freed with free. 85 * 86 * NOTE: If |cbs| contains NUL bytes, the string will be truncated. Call 87 * |CBS_contains_zero_byte(cbs)| to check for NUL bytes. 88 */ 89 int CBS_strdup(const CBS *cbs, char **out_ptr); 90 91 /* 92 * CBS_write_bytes writes all of the remaining data from |cbs| into |dst| 93 * if it is at most |dst_len| bytes. If |copied| is not NULL, it will be set 94 * to the amount copied. It returns one on success and zero otherwise. 95 */ 96 int CBS_write_bytes(const CBS *cbs, uint8_t *dst, size_t dst_len, 97 size_t *copied); 98 99 /* 100 * CBS_contains_zero_byte returns one if the current contents of |cbs| contains 101 * a NUL byte and zero otherwise. 102 */ 103 int CBS_contains_zero_byte(const CBS *cbs); 104 105 /* 106 * CBS_mem_equal compares the current contents of |cbs| with the |len| bytes 107 * starting at |data|. If they're equal, it returns one, otherwise zero. If the 108 * lengths match, it uses a constant-time comparison. 109 */ 110 int CBS_mem_equal(const CBS *cbs, const uint8_t *data, size_t len); 111 112 /* 113 * CBS_get_u8 sets |*out| to the next uint8_t from |cbs| and advances |cbs|. It 114 * returns one on success and zero on error. 115 */ 116 int CBS_get_u8(CBS *cbs, uint8_t *out); 117 118 /* 119 * CBS_get_u16 sets |*out| to the next, big-endian uint16_t from |cbs| and 120 * advances |cbs|. It returns one on success and zero on error. 121 */ 122 int CBS_get_u16(CBS *cbs, uint16_t *out); 123 124 /* 125 * CBS_get_u24 sets |*out| to the next, big-endian 24-bit value from |cbs| and 126 * advances |cbs|. It returns one on success and zero on error. 127 */ 128 int CBS_get_u24(CBS *cbs, uint32_t *out); 129 130 /* 131 * CBS_get_u32 sets |*out| to the next, big-endian uint32_t value from |cbs| 132 * and advances |cbs|. It returns one on success and zero on error. 133 */ 134 int CBS_get_u32(CBS *cbs, uint32_t *out); 135 136 /* 137 * CBS_get_u64 sets |*out| to the next, big-endian uint64_t value from |cbs| 138 * and advances |cbs|. It returns one on success and zero on error. 139 */ 140 int CBS_get_u64(CBS *cbs, uint64_t *out); 141 142 /* 143 * CBS_get_last_u8 sets |*out| to the last uint8_t from |cbs| and shortens 144 * |cbs|. It returns one on success and zero on error. 145 */ 146 int CBS_get_last_u8(CBS *cbs, uint8_t *out); 147 148 /* 149 * CBS_get_bytes sets |*out| to the next |len| bytes from |cbs| and advances 150 * |cbs|. It returns one on success and zero on error. 151 */ 152 int CBS_get_bytes(CBS *cbs, CBS *out, size_t len); 153 154 /* 155 * CBS_get_u8_length_prefixed sets |*out| to the contents of an 8-bit, 156 * length-prefixed value from |cbs| and advances |cbs| over it. It returns one 157 * on success and zero on error. 158 */ 159 int CBS_get_u8_length_prefixed(CBS *cbs, CBS *out); 160 161 /* 162 * CBS_get_u16_length_prefixed sets |*out| to the contents of a 16-bit, 163 * big-endian, length-prefixed value from |cbs| and advances |cbs| over it. It 164 * returns one on success and zero on error. 165 */ 166 int CBS_get_u16_length_prefixed(CBS *cbs, CBS *out); 167 168 /* 169 * CBS_get_u24_length_prefixed sets |*out| to the contents of a 24-bit, 170 * big-endian, length-prefixed value from |cbs| and advances |cbs| over it. It 171 * returns one on success and zero on error. 172 */ 173 int CBS_get_u24_length_prefixed(CBS *cbs, CBS *out); 174 175 /* 176 * CBS_peek_u8 sets |*out| to the next uint8_t from |cbs|, but does not advance 177 * |cbs|. It returns one on success and zero on error. 178 */ 179 int CBS_peek_u8(CBS *cbs, uint8_t *out); 180 181 /* 182 * CBS_peek_u16 sets |*out| to the next, big-endian uint16_t from |cbs|, but 183 * does not advance |cbs|. It returns one on success and zero on error. 184 */ 185 int CBS_peek_u16(CBS *cbs, uint16_t *out); 186 187 /* 188 * CBS_peek_u24 sets |*out| to the next, big-endian 24-bit value from |cbs|, but 189 * does not advance |cbs|. It returns one on success and zero on error. 190 */ 191 int CBS_peek_u24(CBS *cbs, uint32_t *out); 192 193 /* 194 * CBS_peek_u32 sets |*out| to the next, big-endian uint32_t value from |cbs|, 195 * but does not advance |cbs|. It returns one on success and zero on error. 196 */ 197 int CBS_peek_u32(CBS *cbs, uint32_t *out); 198 199 /* 200 * CBS_peek_last_u8 sets |*out| to the last uint8_t from |cbs|, but does not 201 * shorten |cbs|. It returns one on success and zero on error. 202 */ 203 int CBS_peek_last_u8(CBS *cbs, uint8_t *out); 204 205 206 /* Parsing ASN.1 */ 207 208 /* 209 * While an identifier can be multiple octets, this library only handles the 210 * single octet variety currently. This limits support up to tag number 30 211 * since tag number 31 is a reserved value to indicate multiple octets. 212 */ 213 214 /* Bits 8 and 7: class tag type: See X.690 section 8.1.2.2. */ 215 #define CBS_ASN1_UNIVERSAL 0x00 216 #define CBS_ASN1_APPLICATION 0x40 217 #define CBS_ASN1_CONTEXT_SPECIFIC 0x80 218 #define CBS_ASN1_PRIVATE 0xc0 219 220 /* Bit 6: Primitive or constructed: See X.690 section 8.1.2.3. */ 221 #define CBS_ASN1_PRIMITIVE 0x00 222 #define CBS_ASN1_CONSTRUCTED 0x20 223 224 /* 225 * Bits 5 to 1 are the tag number. See X.680 section 8.6 for tag numbers of 226 * the universal class. 227 */ 228 229 /* 230 * Common universal identifier octets. 231 * See X.690 section 8.1 and X.680 section 8.6 for universal tag numbers. 232 * 233 * Note: These definitions are the cause of some of the strange behavior in 234 * CBS's bs_ber.c. 235 * 236 * In BER, it is the sender's option to use primitive or constructed for 237 * bitstring (X.690 section 8.6.1) and octetstring (X.690 section 8.7.1). 238 * 239 * In DER, bitstring and octetstring are required to be primitive 240 * (X.690 section 10.2). 241 */ 242 #define CBS_ASN1_BOOLEAN (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0x1) 243 #define CBS_ASN1_INTEGER (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0x2) 244 #define CBS_ASN1_BITSTRING (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0x3) 245 #define CBS_ASN1_OCTETSTRING (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0x4) 246 #define CBS_ASN1_OBJECT (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0x6) 247 #define CBS_ASN1_ENUMERATED (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0xa) 248 #define CBS_ASN1_SEQUENCE (CBS_ASN1_UNIVERSAL | CBS_ASN1_CONSTRUCTED | 0x10) 249 #define CBS_ASN1_SET (CBS_ASN1_UNIVERSAL | CBS_ASN1_CONSTRUCTED | 0x11) 250 251 /* 252 * CBS_get_asn1 sets |*out| to the contents of DER-encoded, ASN.1 element (not 253 * including tag and length bytes) and advances |cbs| over it. The ASN.1 254 * element must match |tag_value|. It returns one on success and zero 255 * on error. 256 * 257 * Tag numbers greater than 30 are not supported (i.e. short form only). 258 */ 259 int CBS_get_asn1(CBS *cbs, CBS *out, unsigned int tag_value); 260 261 /* 262 * CBS_get_asn1_element acts like |CBS_get_asn1| but |out| will include the 263 * ASN.1 header bytes too. 264 */ 265 int CBS_get_asn1_element(CBS *cbs, CBS *out, unsigned int tag_value); 266 267 /* 268 * CBS_peek_asn1_tag looks ahead at the next ASN.1 tag and returns one 269 * if the next ASN.1 element on |cbs| would have tag |tag_value|. If 270 * |cbs| is empty or the tag does not match, it returns zero. Note: if 271 * it returns one, CBS_get_asn1 may still fail if the rest of the 272 * element is malformed. 273 */ 274 int CBS_peek_asn1_tag(const CBS *cbs, unsigned int tag_value); 275 276 /* 277 * CBS_get_any_asn1_element sets |*out| to contain the next ASN.1 element from 278 * |*cbs| (including header bytes) and advances |*cbs|. It sets |*out_tag| to 279 * the tag number and |*out_header_len| to the length of the ASN.1 header. 280 * Each of |out|, |out_tag|, and |out_header_len| may be NULL to ignore 281 * the value. 282 * 283 * Tag numbers greater than 30 are not supported (i.e. short form only). 284 */ 285 int CBS_get_any_asn1_element(CBS *cbs, CBS *out, unsigned int *out_tag, 286 size_t *out_header_len); 287 288 /* 289 * CBS_get_asn1_uint64 gets an ASN.1 INTEGER from |cbs| using |CBS_get_asn1| 290 * and sets |*out| to its value. It returns one on success and zero on error, 291 * where error includes the integer being negative, or too large to represent 292 * in 64 bits. 293 */ 294 int CBS_get_asn1_uint64(CBS *cbs, uint64_t *out); 295 296 /* 297 * CBS_get_optional_asn1 gets an optional explicitly-tagged element 298 * from |cbs| tagged with |tag| and sets |*out| to its contents. If 299 * present, it sets |*out_present| to one, otherwise zero. It returns 300 * one on success, whether or not the element was present, and zero on 301 * decode failure. 302 */ 303 int CBS_get_optional_asn1(CBS *cbs, CBS *out, int *out_present, 304 unsigned int tag); 305 306 /* 307 * CBS_get_optional_asn1_octet_string gets an optional 308 * explicitly-tagged OCTET STRING from |cbs|. If present, it sets 309 * |*out| to the string and |*out_present| to one. Otherwise, it sets 310 * |*out| to empty and |*out_present| to zero. |out_present| may be 311 * NULL. It returns one on success, whether or not the element was 312 * present, and zero on decode failure. 313 */ 314 int CBS_get_optional_asn1_octet_string(CBS *cbs, CBS *out, int *out_present, 315 unsigned int tag); 316 317 /* 318 * CBS_get_optional_asn1_uint64 gets an optional explicitly-tagged 319 * INTEGER from |cbs|. If present, it sets |*out| to the 320 * value. Otherwise, it sets |*out| to |default_value|. It returns one 321 * on success, whether or not the element was present, and zero on 322 * decode failure. 323 */ 324 int CBS_get_optional_asn1_uint64(CBS *cbs, uint64_t *out, unsigned int tag, 325 uint64_t default_value); 326 327 /* 328 * CBS_get_optional_asn1_bool gets an optional, explicitly-tagged BOOLEAN from 329 * |cbs|. If present, it sets |*out| to either zero or one, based on the 330 * boolean. Otherwise, it sets |*out| to |default_value|. It returns one on 331 * success, whether or not the element was present, and zero on decode 332 * failure. 333 */ 334 int CBS_get_optional_asn1_bool(CBS *cbs, int *out, unsigned int tag, 335 int default_value); 336 337 338 /* 339 * CRYPTO ByteBuilder. 340 * 341 * |CBB| objects allow one to build length-prefixed serialisations. A |CBB| 342 * object is associated with a buffer and new buffers are created with 343 * |CBB_init|. Several |CBB| objects can point at the same buffer when a 344 * length-prefix is pending, however only a single |CBB| can be 'current' at 345 * any one time. For example, if one calls |CBB_add_u8_length_prefixed| then 346 * the new |CBB| points at the same buffer as the original. But if the original 347 * |CBB| is used then the length prefix is written out and the new |CBB| must 348 * not be used again. 349 * 350 * If one needs to force a length prefix to be written out because a |CBB| is 351 * going out of scope, use |CBB_flush|. 352 */ 353 354 struct cbb_buffer_st { 355 uint8_t *buf; 356 357 /* The number of valid bytes. */ 358 size_t len; 359 360 /* The size of buf. */ 361 size_t cap; 362 363 /* 364 * One iff |buf| is owned by this object. If not then |buf| cannot be 365 * resized. 366 */ 367 char can_resize; 368 }; 369 370 typedef struct cbb_st { 371 struct cbb_buffer_st *base; 372 373 /* 374 * offset is the offset from the start of |base->buf| to the position of any 375 * pending length-prefix. 376 */ 377 size_t offset; 378 379 /* child points to a child CBB if a length-prefix is pending. */ 380 struct cbb_st *child; 381 382 /* 383 * pending_len_len contains the number of bytes in a pending length-prefix, 384 * or zero if no length-prefix is pending. 385 */ 386 uint8_t pending_len_len; 387 388 char pending_is_asn1; 389 390 /* 391 * is_top_level is true iff this is a top-level |CBB| (as opposed to a child 392 * |CBB|). Top-level objects are valid arguments for |CBB_finish|. 393 */ 394 char is_top_level; 395 } CBB; 396 397 /* 398 * CBB_init initialises |cbb| with |initial_capacity|. Since a |CBB| grows as 399 * needed, the |initial_capacity| is just a hint. It returns one on success or 400 * zero on error. 401 */ 402 int CBB_init(CBB *cbb, size_t initial_capacity); 403 404 /* 405 * CBB_init_fixed initialises |cbb| to write to |len| bytes at |buf|. Since 406 * |buf| cannot grow, trying to write more than |len| bytes will cause CBB 407 * functions to fail. It returns one on success or zero on error. 408 */ 409 int CBB_init_fixed(CBB *cbb, uint8_t *buf, size_t len); 410 411 /* 412 * CBB_cleanup frees all resources owned by |cbb| and other |CBB| objects 413 * writing to the same buffer. This should be used in an error case where a 414 * serialisation is abandoned. 415 */ 416 void CBB_cleanup(CBB *cbb); 417 418 /* 419 * CBB_finish completes any pending length prefix and sets |*out_data| to a 420 * malloced buffer and |*out_len| to the length of that buffer. The caller 421 * takes ownership of the buffer and, unless the buffer was fixed with 422 * |CBB_init_fixed|, must call |free| when done. 423 * 424 * It can only be called on a "top level" |CBB|, i.e. one initialised with 425 * |CBB_init| or |CBB_init_fixed|. It returns one on success and zero on 426 * error. 427 */ 428 int CBB_finish(CBB *cbb, uint8_t **out_data, size_t *out_len); 429 430 /* 431 * CBB_flush causes any pending length prefixes to be written out and any child 432 * |CBB| objects of |cbb| to be invalidated. It returns one on success or zero 433 * on error. 434 */ 435 int CBB_flush(CBB *cbb); 436 437 /* 438 * CBB_discard_child discards the current unflushed child of |cbb|. Neither the 439 * child's contents nor the length prefix will be included in the output. 440 */ 441 void CBB_discard_child(CBB *cbb); 442 443 /* 444 * CBB_add_u8_length_prefixed sets |*out_contents| to a new child of |cbb|. The 445 * data written to |*out_contents| will be prefixed in |cbb| with an 8-bit 446 * length. It returns one on success or zero on error. 447 */ 448 int CBB_add_u8_length_prefixed(CBB *cbb, CBB *out_contents); 449 450 /* 451 * CBB_add_u16_length_prefixed sets |*out_contents| to a new child of |cbb|. 452 * The data written to |*out_contents| will be prefixed in |cbb| with a 16-bit, 453 * big-endian length. It returns one on success or zero on error. 454 */ 455 int CBB_add_u16_length_prefixed(CBB *cbb, CBB *out_contents); 456 457 /* 458 * CBB_add_u24_length_prefixed sets |*out_contents| to a new child of |cbb|. 459 * The data written to |*out_contents| will be prefixed in |cbb| with a 24-bit, 460 * big-endian length. It returns one on success or zero on error. 461 */ 462 int CBB_add_u24_length_prefixed(CBB *cbb, CBB *out_contents); 463 464 /* 465 * CBB_add_asn sets |*out_contents| to a |CBB| into which the contents of an 466 * ASN.1 object can be written. The |tag| argument will be used as the tag for 467 * the object. Passing in |tag| number 31 will return in an error since only 468 * single octet identifiers are supported. It returns one on success or zero 469 * on error. 470 */ 471 int CBB_add_asn1(CBB *cbb, CBB *out_contents, unsigned int tag); 472 473 /* 474 * CBB_add_bytes appends |len| bytes from |data| to |cbb|. It returns one on 475 * success and zero otherwise. 476 */ 477 int CBB_add_bytes(CBB *cbb, const uint8_t *data, size_t len); 478 479 /* 480 * CBB_add_space appends |len| bytes to |cbb| and sets |*out_data| to point to 481 * the beginning of that space. The caller must then write |len| bytes of 482 * actual contents to |*out_data|. It returns one on success and zero 483 * otherwise. 484 */ 485 int CBB_add_space(CBB *cbb, uint8_t **out_data, size_t len); 486 487 /* 488 * CBB_add_u8 appends an 8-bit number from |value| to |cbb|. It returns one on 489 * success and zero otherwise. 490 */ 491 int CBB_add_u8(CBB *cbb, size_t value); 492 493 /* 494 * CBB_add_u8 appends a 16-bit, big-endian number from |value| to |cbb|. It 495 * returns one on success and zero otherwise. 496 */ 497 int CBB_add_u16(CBB *cbb, size_t value); 498 499 /* 500 * CBB_add_u24 appends a 24-bit, big-endian number from |value| to |cbb|. It 501 * returns one on success and zero otherwise. 502 */ 503 int CBB_add_u24(CBB *cbb, size_t value); 504 505 /* 506 * CBB_add_u32 appends a 32-bit, big-endian number from |value| to |cbb|. It 507 * returns one on success and zero otherwise. 508 */ 509 int CBB_add_u32(CBB *cbb, size_t value); 510 511 /* 512 * CBB_add_u64 appends a 64-bit, big-endian number from |value| to |cbb|. It 513 * returns one on success and zero otherwise. 514 */ 515 int CBB_add_u64(CBB *cbb, uint64_t value); 516 517 /* 518 * CBB_add_asn1_uint64 writes an ASN.1 INTEGER into |cbb| using |CBB_add_asn1| 519 * and writes |value| in its contents. It returns one on success and zero on 520 * error. 521 */ 522 int CBB_add_asn1_uint64(CBB *cbb, uint64_t value); 523 524 #ifdef LIBRESSL_INTERNAL 525 /* 526 * CBS_dup sets |out| to point to cbs's |data| and |len|. It results in two 527 * CBS that point to the same buffer. 528 */ 529 void CBS_dup(const CBS *cbs, CBS *out); 530 531 /* 532 * cbs_get_any_asn1_element sets |*out| to contain the next ASN.1 element from 533 * |*cbs| (including header bytes) and advances |*cbs|. It sets |*out_tag| to 534 * the tag number and |*out_header_len| to the length of the ASN.1 header. If 535 * strict mode is disabled and the element has indefinite length then |*out| 536 * will only contain the header. Each of |out|, |out_tag|, and 537 * |out_header_len| may be NULL to ignore the value. 538 * 539 * Tag numbers greater than 30 are not supported (i.e. short form only). 540 */ 541 int cbs_get_any_asn1_element_internal(CBS *cbs, CBS *out, unsigned int *out_tag, 542 size_t *out_header_len, int strict); 543 544 /* 545 * CBS_asn1_indefinite_to_definite reads an ASN.1 structure from |in|. If it 546 * finds indefinite-length elements that otherwise appear to be valid DER, it 547 * attempts to convert the DER-like data to DER and sets |*out| and 548 * |*out_length| to describe a malloced buffer containing the DER data. 549 * Additionally, |*in| will be advanced over the ASN.1 data. 550 * 551 * If it doesn't find any indefinite-length elements then it sets |*out| to 552 * NULL and |*in| is unmodified. 553 * 554 * This is NOT a conversion from BER to DER. There are many restrictions when 555 * dealing with DER data. This is only concerned with one: indefinite vs. 556 * definite form. However, this suffices to handle the PKCS#7 and PKCS#12 output 557 * from NSS. 558 * 559 * It returns one on success and zero otherwise. 560 */ 561 int CBS_asn1_indefinite_to_definite(CBS *in, uint8_t **out, size_t *out_len); 562 #endif /* LIBRESSL_INTERNAL */ 563 564 __END_HIDDEN_DECLS 565 566 #endif /* OPENSSL_HEADER_BYTESTRING_H */ 567