1*d7a08d8fSdoug /* $OpenBSD: bytestring.h,v 1.4 2015/02/07 06:10:32 doug Exp $ */ 2c4905cd3Sdoug /* 3c4905cd3Sdoug * Copyright (c) 2014, Google Inc. 4c4905cd3Sdoug * 5c4905cd3Sdoug * Permission to use, copy, modify, and/or distribute this software for any 6c4905cd3Sdoug * purpose with or without fee is hereby granted, provided that the above 7c4905cd3Sdoug * copyright notice and this permission notice appear in all copies. 8c4905cd3Sdoug * 9c4905cd3Sdoug * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10c4905cd3Sdoug * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11c4905cd3Sdoug * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 12c4905cd3Sdoug * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13c4905cd3Sdoug * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION 14c4905cd3Sdoug * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 15c4905cd3Sdoug * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ 16c4905cd3Sdoug 17c4905cd3Sdoug #ifndef OPENSSL_HEADER_BYTESTRING_H 18c4905cd3Sdoug #define OPENSSL_HEADER_BYTESTRING_H 19c4905cd3Sdoug 20c4905cd3Sdoug #if defined(__cplusplus) 21c4905cd3Sdoug extern "C" { 22c4905cd3Sdoug #endif 23c4905cd3Sdoug 24c4905cd3Sdoug #include <sys/types.h> 25c4905cd3Sdoug #include <stdint.h> 26c4905cd3Sdoug 27c4905cd3Sdoug #include <openssl/opensslconf.h> 28c4905cd3Sdoug 29732f1cb2Sdoug /* 30732f1cb2Sdoug * Bytestrings are used for parsing and building TLS and ASN.1 messages. 31c4905cd3Sdoug * 32c4905cd3Sdoug * A "CBS" (CRYPTO ByteString) represents a string of bytes in memory and 33c4905cd3Sdoug * provides utility functions for safely parsing length-prefixed structures 34c4905cd3Sdoug * like TLS and ASN.1 from it. 35c4905cd3Sdoug * 36c4905cd3Sdoug * A "CBB" (CRYPTO ByteBuilder) is a memory buffer that grows as needed and 37732f1cb2Sdoug * provides utility functions for building length-prefixed messages. 38732f1cb2Sdoug */ 39c4905cd3Sdoug 40c4905cd3Sdoug /* CRYPTO ByteString */ 41c4905cd3Sdoug typedef struct cbs_st { 42c4905cd3Sdoug const uint8_t *data; 43c4905cd3Sdoug size_t len; 44c4905cd3Sdoug } CBS; 45c4905cd3Sdoug 46732f1cb2Sdoug /* 47732f1cb2Sdoug * CBS_init sets |cbs| to point to |data|. It does not take ownership of 48732f1cb2Sdoug * |data|. 49732f1cb2Sdoug */ 50c4905cd3Sdoug void CBS_init(CBS *cbs, const uint8_t *data, size_t len); 51c4905cd3Sdoug 52732f1cb2Sdoug /* 53732f1cb2Sdoug * CBS_skip advances |cbs| by |len| bytes. It returns one on success and zero 54732f1cb2Sdoug * otherwise. 55732f1cb2Sdoug */ 56c4905cd3Sdoug int CBS_skip(CBS *cbs, size_t len); 57c4905cd3Sdoug 58732f1cb2Sdoug /* 593b087d0eSdoug * CBS_data returns a pointer to the contents of |cbs|. 60732f1cb2Sdoug */ 61c4905cd3Sdoug const uint8_t *CBS_data(const CBS *cbs); 62c4905cd3Sdoug 63732f1cb2Sdoug /* 64732f1cb2Sdoug * CBS_len returns the number of bytes remaining in |cbs|. 65732f1cb2Sdoug */ 66c4905cd3Sdoug size_t CBS_len(const CBS *cbs); 67c4905cd3Sdoug 68732f1cb2Sdoug /* 69732f1cb2Sdoug * CBS_stow copies the current contents of |cbs| into |*out_ptr| and 70c4905cd3Sdoug * |*out_len|. If |*out_ptr| is not NULL, the contents are freed with 71c4905cd3Sdoug * OPENSSL_free. It returns one on success and zero on allocation failure. On 72c4905cd3Sdoug * success, |*out_ptr| should be freed with OPENSSL_free. If |cbs| is empty, 73732f1cb2Sdoug * |*out_ptr| will be NULL. 74732f1cb2Sdoug */ 75c4905cd3Sdoug int CBS_stow(const CBS *cbs, uint8_t **out_ptr, size_t *out_len); 76c4905cd3Sdoug 77732f1cb2Sdoug /* 78732f1cb2Sdoug * CBS_strdup copies the current contents of |cbs| into |*out_ptr| as a 79c4905cd3Sdoug * NUL-terminated C string. If |*out_ptr| is not NULL, the contents are freed 80c4905cd3Sdoug * with OPENSSL_free. It returns one on success and zero on allocation 81c4905cd3Sdoug * failure. On success, |*out_ptr| should be freed with OPENSSL_free. 82c4905cd3Sdoug * 83c4905cd3Sdoug * NOTE: If |cbs| contains NUL bytes, the string will be truncated. Call 84732f1cb2Sdoug * |CBS_contains_zero_byte(cbs)| to check for NUL bytes. 85732f1cb2Sdoug */ 86c4905cd3Sdoug int CBS_strdup(const CBS *cbs, char **out_ptr); 87c4905cd3Sdoug 88732f1cb2Sdoug /* 89732f1cb2Sdoug * CBS_contains_zero_byte returns one if the current contents of |cbs| contains 90732f1cb2Sdoug * a NUL byte and zero otherwise. 91732f1cb2Sdoug */ 92c4905cd3Sdoug int CBS_contains_zero_byte(const CBS *cbs); 93c4905cd3Sdoug 94732f1cb2Sdoug /* 95732f1cb2Sdoug * CBS_mem_equal compares the current contents of |cbs| with the |len| bytes 96c4905cd3Sdoug * starting at |data|. If they're equal, it returns one, otherwise zero. If the 97732f1cb2Sdoug * lengths match, it uses a constant-time comparison. 98732f1cb2Sdoug */ 99732f1cb2Sdoug int CBS_mem_equal(const CBS *cbs, const uint8_t *data, size_t len); 100c4905cd3Sdoug 101732f1cb2Sdoug /* 102732f1cb2Sdoug * CBS_get_u8 sets |*out| to the next uint8_t from |cbs| and advances |cbs|. It 103732f1cb2Sdoug * returns one on success and zero on error. 104732f1cb2Sdoug */ 105c4905cd3Sdoug int CBS_get_u8(CBS *cbs, uint8_t *out); 106c4905cd3Sdoug 107732f1cb2Sdoug /* 108732f1cb2Sdoug * CBS_get_u16 sets |*out| to the next, big-endian uint16_t from |cbs| and 109732f1cb2Sdoug * advances |cbs|. It returns one on success and zero on error. 110732f1cb2Sdoug */ 111c4905cd3Sdoug int CBS_get_u16(CBS *cbs, uint16_t *out); 112c4905cd3Sdoug 113732f1cb2Sdoug /* 114732f1cb2Sdoug * CBS_get_u24 sets |*out| to the next, big-endian 24-bit value from |cbs| and 115732f1cb2Sdoug * advances |cbs|. It returns one on success and zero on error. 116732f1cb2Sdoug */ 117c4905cd3Sdoug int CBS_get_u24(CBS *cbs, uint32_t *out); 118c4905cd3Sdoug 119732f1cb2Sdoug /* 120732f1cb2Sdoug * CBS_get_u32 sets |*out| to the next, big-endian uint32_t value from |cbs| 121732f1cb2Sdoug * and advances |cbs|. It returns one on success and zero on error. 122732f1cb2Sdoug */ 123c4905cd3Sdoug int CBS_get_u32(CBS *cbs, uint32_t *out); 124c4905cd3Sdoug 125732f1cb2Sdoug /* 126732f1cb2Sdoug * CBS_get_bytes sets |*out| to the next |len| bytes from |cbs| and advances 127732f1cb2Sdoug * |cbs|. It returns one on success and zero on error. 128732f1cb2Sdoug */ 129c4905cd3Sdoug int CBS_get_bytes(CBS *cbs, CBS *out, size_t len); 130c4905cd3Sdoug 131732f1cb2Sdoug /* 132732f1cb2Sdoug * CBS_get_u8_length_prefixed sets |*out| to the contents of an 8-bit, 133c4905cd3Sdoug * length-prefixed value from |cbs| and advances |cbs| over it. It returns one 134732f1cb2Sdoug * on success and zero on error. 135732f1cb2Sdoug */ 136c4905cd3Sdoug int CBS_get_u8_length_prefixed(CBS *cbs, CBS *out); 137c4905cd3Sdoug 138732f1cb2Sdoug /* 139732f1cb2Sdoug * CBS_get_u16_length_prefixed sets |*out| to the contents of a 16-bit, 140c4905cd3Sdoug * big-endian, length-prefixed value from |cbs| and advances |cbs| over it. It 141732f1cb2Sdoug * returns one on success and zero on error. 142732f1cb2Sdoug */ 143c4905cd3Sdoug int CBS_get_u16_length_prefixed(CBS *cbs, CBS *out); 144c4905cd3Sdoug 145732f1cb2Sdoug /* 146732f1cb2Sdoug * CBS_get_u24_length_prefixed sets |*out| to the contents of a 24-bit, 147c4905cd3Sdoug * big-endian, length-prefixed value from |cbs| and advances |cbs| over it. It 148732f1cb2Sdoug * returns one on success and zero on error. 149732f1cb2Sdoug */ 150c4905cd3Sdoug int CBS_get_u24_length_prefixed(CBS *cbs, CBS *out); 151c4905cd3Sdoug 152c4905cd3Sdoug 153c4905cd3Sdoug /* Parsing ASN.1 */ 154c4905cd3Sdoug 155c4905cd3Sdoug #define CBS_ASN1_BOOLEAN 0x1 156c4905cd3Sdoug #define CBS_ASN1_INTEGER 0x2 157c4905cd3Sdoug #define CBS_ASN1_BITSTRING 0x3 158c4905cd3Sdoug #define CBS_ASN1_OCTETSTRING 0x4 159c4905cd3Sdoug #define CBS_ASN1_OBJECT 0x6 160c4905cd3Sdoug #define CBS_ASN1_ENUMERATED 0xa 161c4905cd3Sdoug #define CBS_ASN1_SEQUENCE (0x10 | CBS_ASN1_CONSTRUCTED) 162c4905cd3Sdoug #define CBS_ASN1_SET (0x11 | CBS_ASN1_CONSTRUCTED) 163c4905cd3Sdoug 164c4905cd3Sdoug #define CBS_ASN1_CONSTRUCTED 0x20 165c4905cd3Sdoug #define CBS_ASN1_CONTEXT_SPECIFIC 0x80 166c4905cd3Sdoug 167732f1cb2Sdoug /* 168732f1cb2Sdoug * CBS_get_asn1 sets |*out| to the contents of DER-encoded, ASN.1 element (not 169c4905cd3Sdoug * including tag and length bytes) and advances |cbs| over it. The ASN.1 170c4905cd3Sdoug * element must match |tag_value|. It returns one on success and zero 171c4905cd3Sdoug * on error. 172c4905cd3Sdoug * 1733b087d0eSdoug * Tag numbers greater than 30 are not supported (i.e. short form only). 174732f1cb2Sdoug */ 175c4905cd3Sdoug int CBS_get_asn1(CBS *cbs, CBS *out, unsigned tag_value); 176c4905cd3Sdoug 177732f1cb2Sdoug /* 178732f1cb2Sdoug * CBS_get_asn1_element acts like |CBS_get_asn1| but |out| will include the 179732f1cb2Sdoug * ASN.1 header bytes too. 180732f1cb2Sdoug */ 181c4905cd3Sdoug int CBS_get_asn1_element(CBS *cbs, CBS *out, unsigned tag_value); 182c4905cd3Sdoug 183732f1cb2Sdoug /* 184732f1cb2Sdoug * CBS_peek_asn1_tag looks ahead at the next ASN.1 tag and returns one 185c4905cd3Sdoug * if the next ASN.1 element on |cbs| would have tag |tag_value|. If 186c4905cd3Sdoug * |cbs| is empty or the tag does not match, it returns zero. Note: if 187c4905cd3Sdoug * it returns one, CBS_get_asn1 may still fail if the rest of the 188732f1cb2Sdoug * element is malformed. 189732f1cb2Sdoug */ 190c4905cd3Sdoug int CBS_peek_asn1_tag(const CBS *cbs, unsigned tag_value); 191c4905cd3Sdoug 192732f1cb2Sdoug /* 193732f1cb2Sdoug * CBS_get_any_asn1_element sets |*out| to contain the next ASN.1 element from 194c4905cd3Sdoug * |*cbs| (including header bytes) and advances |*cbs|. It sets |*out_tag| to 195c4905cd3Sdoug * the tag number and |*out_header_len| to the length of the ASN.1 header. If 196c4905cd3Sdoug * the element has indefinite length then |*out| will only contain the 197c4905cd3Sdoug * header. Each of |out|, |out_tag|, and |out_header_len| may be NULL to ignore 198c4905cd3Sdoug * the value. 199c4905cd3Sdoug * 2003b087d0eSdoug * Tag numbers greater than 30 are not supported (i.e. short form only). 201732f1cb2Sdoug */ 202732f1cb2Sdoug int CBS_get_any_asn1_element(CBS *cbs, CBS *out, unsigned *out_tag, 203c4905cd3Sdoug size_t *out_header_len); 204c4905cd3Sdoug 205732f1cb2Sdoug /* 206732f1cb2Sdoug * CBS_get_asn1_uint64 gets an ASN.1 INTEGER from |cbs| using |CBS_get_asn1| 207c4905cd3Sdoug * and sets |*out| to its value. It returns one on success and zero on error, 208c4905cd3Sdoug * where error includes the integer being negative, or too large to represent 209732f1cb2Sdoug * in 64 bits. 210732f1cb2Sdoug */ 211c4905cd3Sdoug int CBS_get_asn1_uint64(CBS *cbs, uint64_t *out); 212c4905cd3Sdoug 213732f1cb2Sdoug /* 214732f1cb2Sdoug * CBS_get_optional_asn1 gets an optional explicitly-tagged element 215c4905cd3Sdoug * from |cbs| tagged with |tag| and sets |*out| to its contents. If 216c4905cd3Sdoug * present, it sets |*out_present| to one, otherwise zero. It returns 217c4905cd3Sdoug * one on success, whether or not the element was present, and zero on 218732f1cb2Sdoug * decode failure. 219732f1cb2Sdoug */ 220732f1cb2Sdoug int CBS_get_optional_asn1(CBS *cbs, CBS *out, int *out_present, unsigned tag); 221c4905cd3Sdoug 222732f1cb2Sdoug /* 223732f1cb2Sdoug * CBS_get_optional_asn1_octet_string gets an optional 224c4905cd3Sdoug * explicitly-tagged OCTET STRING from |cbs|. If present, it sets 225c4905cd3Sdoug * |*out| to the string and |*out_present| to one. Otherwise, it sets 226c4905cd3Sdoug * |*out| to empty and |*out_present| to zero. |out_present| may be 227c4905cd3Sdoug * NULL. It returns one on success, whether or not the element was 228732f1cb2Sdoug * present, and zero on decode failure. 229732f1cb2Sdoug */ 230732f1cb2Sdoug int CBS_get_optional_asn1_octet_string(CBS *cbs, CBS *out, int *out_present, 231c4905cd3Sdoug unsigned tag); 232c4905cd3Sdoug 233732f1cb2Sdoug /* 234732f1cb2Sdoug * CBS_get_optional_asn1_uint64 gets an optional explicitly-tagged 235c4905cd3Sdoug * INTEGER from |cbs|. If present, it sets |*out| to the 236c4905cd3Sdoug * value. Otherwise, it sets |*out| to |default_value|. It returns one 237c4905cd3Sdoug * on success, whether or not the element was present, and zero on 238732f1cb2Sdoug * decode failure. 239732f1cb2Sdoug */ 240732f1cb2Sdoug int CBS_get_optional_asn1_uint64(CBS *cbs, uint64_t *out, unsigned tag, 241c4905cd3Sdoug uint64_t default_value); 242c4905cd3Sdoug 243732f1cb2Sdoug /* 244732f1cb2Sdoug * CBS_get_optional_asn1_bool gets an optional, explicitly-tagged BOOLEAN from 245c4905cd3Sdoug * |cbs|. If present, it sets |*out| to either zero or one, based on the 246c4905cd3Sdoug * boolean. Otherwise, it sets |*out| to |default_value|. It returns one on 247c4905cd3Sdoug * success, whether or not the element was present, and zero on decode 248732f1cb2Sdoug * failure. 249732f1cb2Sdoug */ 250c4905cd3Sdoug int CBS_get_optional_asn1_bool(CBS *cbs, int *out, unsigned tag, 251c4905cd3Sdoug int default_value); 252c4905cd3Sdoug 253c4905cd3Sdoug 254732f1cb2Sdoug /* 255732f1cb2Sdoug * CRYPTO ByteBuilder. 256c4905cd3Sdoug * 257c4905cd3Sdoug * |CBB| objects allow one to build length-prefixed serialisations. A |CBB| 258c4905cd3Sdoug * object is associated with a buffer and new buffers are created with 259c4905cd3Sdoug * |CBB_init|. Several |CBB| objects can point at the same buffer when a 260c4905cd3Sdoug * length-prefix is pending, however only a single |CBB| can be 'current' at 261c4905cd3Sdoug * any one time. For example, if one calls |CBB_add_u8_length_prefixed| then 262c4905cd3Sdoug * the new |CBB| points at the same buffer as the original. But if the original 263c4905cd3Sdoug * |CBB| is used then the length prefix is written out and the new |CBB| must 264c4905cd3Sdoug * not be used again. 265c4905cd3Sdoug * 266c4905cd3Sdoug * If one needs to force a length prefix to be written out because a |CBB| is 267732f1cb2Sdoug * going out of scope, use |CBB_flush|. 268732f1cb2Sdoug */ 269c4905cd3Sdoug 270c4905cd3Sdoug struct cbb_buffer_st { 271c4905cd3Sdoug uint8_t *buf; 272732f1cb2Sdoug 273732f1cb2Sdoug /* The number of valid bytes. */ 274732f1cb2Sdoug size_t len; 275732f1cb2Sdoug 276732f1cb2Sdoug /* The size of buf. */ 277732f1cb2Sdoug size_t cap; 278732f1cb2Sdoug 279732f1cb2Sdoug /* 280732f1cb2Sdoug * One iff |buf| is owned by this object. If not then |buf| cannot be 281732f1cb2Sdoug * resized. 282732f1cb2Sdoug */ 283732f1cb2Sdoug char can_resize; 284c4905cd3Sdoug }; 285c4905cd3Sdoug 286c4905cd3Sdoug typedef struct cbb_st { 287c4905cd3Sdoug struct cbb_buffer_st *base; 288732f1cb2Sdoug 289732f1cb2Sdoug /* 290732f1cb2Sdoug * offset is the offset from the start of |base->buf| to the position of any 291732f1cb2Sdoug * pending length-prefix. 292732f1cb2Sdoug */ 293c4905cd3Sdoug size_t offset; 294732f1cb2Sdoug 295c4905cd3Sdoug /* child points to a child CBB if a length-prefix is pending. */ 296c4905cd3Sdoug struct cbb_st *child; 297732f1cb2Sdoug 298732f1cb2Sdoug /* 299732f1cb2Sdoug * pending_len_len contains the number of bytes in a pending length-prefix, 300732f1cb2Sdoug * or zero if no length-prefix is pending. 301732f1cb2Sdoug */ 302c4905cd3Sdoug uint8_t pending_len_len; 303732f1cb2Sdoug 304c4905cd3Sdoug char pending_is_asn1; 305732f1cb2Sdoug 306732f1cb2Sdoug /* 307732f1cb2Sdoug * is_top_level is true iff this is a top-level |CBB| (as opposed to a child 308732f1cb2Sdoug * |CBB|). Top-level objects are valid arguments for |CBB_finish|. 309732f1cb2Sdoug */ 310c4905cd3Sdoug char is_top_level; 311c4905cd3Sdoug } CBB; 312c4905cd3Sdoug 313732f1cb2Sdoug /* 314732f1cb2Sdoug * CBB_init initialises |cbb| with |initial_capacity|. Since a |CBB| grows as 315c4905cd3Sdoug * needed, the |initial_capacity| is just a hint. It returns one on success or 316732f1cb2Sdoug * zero on error. 317732f1cb2Sdoug */ 318c4905cd3Sdoug int CBB_init(CBB *cbb, size_t initial_capacity); 319c4905cd3Sdoug 320732f1cb2Sdoug /* 321732f1cb2Sdoug * CBB_init_fixed initialises |cbb| to write to |len| bytes at |buf|. Since 322c4905cd3Sdoug * |buf| cannot grow, trying to write more than |len| bytes will cause CBB 323732f1cb2Sdoug * functions to fail. It returns one on success or zero on error. 324732f1cb2Sdoug */ 325c4905cd3Sdoug int CBB_init_fixed(CBB *cbb, uint8_t *buf, size_t len); 326c4905cd3Sdoug 327732f1cb2Sdoug /* 328732f1cb2Sdoug * CBB_cleanup frees all resources owned by |cbb| and other |CBB| objects 329c4905cd3Sdoug * writing to the same buffer. This should be used in an error case where a 330732f1cb2Sdoug * serialisation is abandoned. 331732f1cb2Sdoug */ 332c4905cd3Sdoug void CBB_cleanup(CBB *cbb); 333c4905cd3Sdoug 334732f1cb2Sdoug /* 335732f1cb2Sdoug * CBB_finish completes any pending length prefix and sets |*out_data| to a 336c4905cd3Sdoug * malloced buffer and |*out_len| to the length of that buffer. The caller 337c4905cd3Sdoug * takes ownership of the buffer and, unless the buffer was fixed with 338c4905cd3Sdoug * |CBB_init_fixed|, must call |OPENSSL_free| when done. 339c4905cd3Sdoug * 340c4905cd3Sdoug * It can only be called on a "top level" |CBB|, i.e. one initialised with 341c4905cd3Sdoug * |CBB_init| or |CBB_init_fixed|. It returns one on success and zero on 342732f1cb2Sdoug * error. 343732f1cb2Sdoug */ 344c4905cd3Sdoug int CBB_finish(CBB *cbb, uint8_t **out_data, size_t *out_len); 345c4905cd3Sdoug 346732f1cb2Sdoug /* 347732f1cb2Sdoug * CBB_flush causes any pending length prefixes to be written out and any child 348c4905cd3Sdoug * |CBB| objects of |cbb| to be invalidated. It returns one on success or zero 349732f1cb2Sdoug * on error. 350732f1cb2Sdoug */ 351c4905cd3Sdoug int CBB_flush(CBB *cbb); 352c4905cd3Sdoug 353732f1cb2Sdoug /* 354732f1cb2Sdoug * CBB_add_u8_length_prefixed sets |*out_contents| to a new child of |cbb|. The 355c4905cd3Sdoug * data written to |*out_contents| will be prefixed in |cbb| with an 8-bit 356732f1cb2Sdoug * length. It returns one on success or zero on error. 357732f1cb2Sdoug */ 358c4905cd3Sdoug int CBB_add_u8_length_prefixed(CBB *cbb, CBB *out_contents); 359c4905cd3Sdoug 360732f1cb2Sdoug /* 361732f1cb2Sdoug * CBB_add_u16_length_prefixed sets |*out_contents| to a new child of |cbb|. 362c4905cd3Sdoug * The data written to |*out_contents| will be prefixed in |cbb| with a 16-bit, 363732f1cb2Sdoug * big-endian length. It returns one on success or zero on error. 364732f1cb2Sdoug */ 365c4905cd3Sdoug int CBB_add_u16_length_prefixed(CBB *cbb, CBB *out_contents); 366c4905cd3Sdoug 367732f1cb2Sdoug /* 368732f1cb2Sdoug * CBB_add_u24_length_prefixed sets |*out_contents| to a new child of |cbb|. 369c4905cd3Sdoug * The data written to |*out_contents| will be prefixed in |cbb| with a 24-bit, 370732f1cb2Sdoug * big-endian length. It returns one on success or zero on error. 371732f1cb2Sdoug */ 372c4905cd3Sdoug int CBB_add_u24_length_prefixed(CBB *cbb, CBB *out_contents); 373c4905cd3Sdoug 374732f1cb2Sdoug /* 375732f1cb2Sdoug * CBB_add_asn sets |*out_contents| to a |CBB| into which the contents of an 376c4905cd3Sdoug * ASN.1 object can be written. The |tag| argument will be used as the tag for 377*d7a08d8fSdoug * the object. Passing in |tag| number 31 will return in an error since only 378*d7a08d8fSdoug * single octet identifiers are supported. It returns one on success or zero 379*d7a08d8fSdoug * on error. 380732f1cb2Sdoug */ 381c4905cd3Sdoug int CBB_add_asn1(CBB *cbb, CBB *out_contents, uint8_t tag); 382c4905cd3Sdoug 383732f1cb2Sdoug /* 384732f1cb2Sdoug * CBB_add_bytes appends |len| bytes from |data| to |cbb|. It returns one on 385732f1cb2Sdoug * success and zero otherwise. 386732f1cb2Sdoug */ 387c4905cd3Sdoug int CBB_add_bytes(CBB *cbb, const uint8_t *data, size_t len); 388c4905cd3Sdoug 389732f1cb2Sdoug /* 390732f1cb2Sdoug * CBB_add_space appends |len| bytes to |cbb| and sets |*out_data| to point to 391c4905cd3Sdoug * the beginning of that space. The caller must then write |len| bytes of 392c4905cd3Sdoug * actual contents to |*out_data|. It returns one on success and zero 393732f1cb2Sdoug * otherwise. 394732f1cb2Sdoug */ 395c4905cd3Sdoug int CBB_add_space(CBB *cbb, uint8_t **out_data, size_t len); 396c4905cd3Sdoug 397732f1cb2Sdoug /* 398732f1cb2Sdoug * CBB_add_u8 appends an 8-bit number from |value| to |cbb|. It returns one on 399732f1cb2Sdoug * success and zero otherwise. 400732f1cb2Sdoug */ 401c4905cd3Sdoug int CBB_add_u8(CBB *cbb, uint8_t value); 402c4905cd3Sdoug 403732f1cb2Sdoug /* 404732f1cb2Sdoug * CBB_add_u8 appends a 16-bit, big-endian number from |value| to |cbb|. It 405732f1cb2Sdoug * returns one on success and zero otherwise. 406732f1cb2Sdoug */ 407c4905cd3Sdoug int CBB_add_u16(CBB *cbb, uint16_t value); 408c4905cd3Sdoug 409732f1cb2Sdoug /* 410732f1cb2Sdoug * CBB_add_u24 appends a 24-bit, big-endian number from |value| to |cbb|. It 411732f1cb2Sdoug * returns one on success and zero otherwise. 412732f1cb2Sdoug */ 413c4905cd3Sdoug int CBB_add_u24(CBB *cbb, uint32_t value); 414c4905cd3Sdoug 415732f1cb2Sdoug /* 416732f1cb2Sdoug * CBB_add_asn1_uint64 writes an ASN.1 INTEGER into |cbb| using |CBB_add_asn1| 417c4905cd3Sdoug * and writes |value| in its contents. It returns one on success and zero on 418732f1cb2Sdoug * error. 419732f1cb2Sdoug */ 420c4905cd3Sdoug int CBB_add_asn1_uint64(CBB *cbb, uint64_t value); 421c4905cd3Sdoug 422c4905cd3Sdoug #ifdef LIBRESSL_INTERNAL 423732f1cb2Sdoug /* 424732f1cb2Sdoug * CBS_asn1_ber_to_der reads an ASN.1 structure from |in|. If it finds 425c4905cd3Sdoug * indefinite-length elements then it attempts to convert the BER data to DER 426c4905cd3Sdoug * and sets |*out| and |*out_length| to describe a malloced buffer containing 427c4905cd3Sdoug * the DER data. Additionally, |*in| will be advanced over the ASN.1 data. 428c4905cd3Sdoug * 429c4905cd3Sdoug * If it doesn't find any indefinite-length elements then it sets |*out| to 430c4905cd3Sdoug * NULL and |*in| is unmodified. 431c4905cd3Sdoug * 432c4905cd3Sdoug * A sufficiently complex ASN.1 structure will break this function because it's 433c4905cd3Sdoug * not possible to generically convert BER to DER without knowledge of the 434c4905cd3Sdoug * structure itself. However, this sufficies to handle the PKCS#7 and #12 output 435c4905cd3Sdoug * from NSS. 436c4905cd3Sdoug * 437732f1cb2Sdoug * It returns one on success and zero otherwise. 438732f1cb2Sdoug */ 439c4905cd3Sdoug int CBS_asn1_ber_to_der(CBS *in, uint8_t **out, size_t *out_len); 440c4905cd3Sdoug #endif /* LIBRESSL_INTERNAL */ 441c4905cd3Sdoug 442c4905cd3Sdoug #if defined(__cplusplus) 443c4905cd3Sdoug } /* extern C */ 444c4905cd3Sdoug #endif 445c4905cd3Sdoug 446c4905cd3Sdoug #endif /* OPENSSL_HEADER_BYTESTRING_H */ 447