Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1 | /* Copyright (c) 2014, Google Inc. |
| 2 | * |
| 3 | * Permission to use, copy, modify, and/or distribute this software for any |
| 4 | * purpose with or without fee is hereby granted, provided that the above |
| 5 | * copyright notice and this permission notice appear in all copies. |
| 6 | * |
| 7 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| 8 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| 9 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY |
| 10 | * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 11 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION |
| 12 | * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN |
| 13 | * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ |
| 14 | |
| 15 | #ifndef OPENSSL_HEADER_AEAD_H |
| 16 | #define OPENSSL_HEADER_AEAD_H |
| 17 | |
| 18 | #include <openssl/base.h> |
| 19 | |
| 20 | #if defined(__cplusplus) |
| 21 | extern "C" { |
| 22 | #endif |
| 23 | |
| 24 | |
| 25 | /* Authenticated Encryption with Additional Data. |
| 26 | * |
Adam Langley | fad6327 | 2015-11-12 12:15:39 -0800 | [diff] [blame] | 27 | * AEAD couples confidentiality and integrity in a single primitive. AEAD |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 28 | * algorithms take a key and then can seal and open individual messages. Each |
| 29 | * message has a unique, per-message nonce and, optionally, additional data |
| 30 | * which is authenticated but not included in the ciphertext. |
| 31 | * |
| 32 | * The |EVP_AEAD_CTX_init| function initialises an |EVP_AEAD_CTX| structure and |
| 33 | * performs any precomputation needed to use |aead| with |key|. The length of |
| 34 | * the key, |key_len|, is given in bytes. |
| 35 | * |
| 36 | * The |tag_len| argument contains the length of the tags, in bytes, and allows |
| 37 | * for the processing of truncated authenticators. A zero value indicates that |
| 38 | * the default tag length should be used and this is defined as |
| 39 | * |EVP_AEAD_DEFAULT_TAG_LENGTH| in order to make the code clear. Using |
| 40 | * truncated tags increases an attacker's chance of creating a valid forgery. |
| 41 | * Be aware that the attacker's chance may increase more than exponentially as |
| 42 | * would naively be expected. |
| 43 | * |
| 44 | * When no longer needed, the initialised |EVP_AEAD_CTX| structure must be |
| 45 | * passed to |EVP_AEAD_CTX_cleanup|, which will deallocate any memory used. |
| 46 | * |
| 47 | * With an |EVP_AEAD_CTX| in hand, one can seal and open messages. These |
| 48 | * operations are intended to meet the standard notions of privacy and |
| 49 | * authenticity for authenticated encryption. For formal definitions see |
| 50 | * Bellare and Namprempre, "Authenticated encryption: relations among notions |
| 51 | * and analysis of the generic composition paradigm," Lecture Notes in Computer |
| 52 | * Science B<1976> (2000), 531–545, |
| 53 | * http://www-cse.ucsd.edu/~mihir/papers/oem.html. |
| 54 | * |
| 55 | * When sealing messages, a nonce must be given. The length of the nonce is |
| 56 | * fixed by the AEAD in use and is returned by |EVP_AEAD_nonce_length|. *The |
| 57 | * nonce must be unique for all messages with the same key*. This is critically |
| 58 | * important - nonce reuse may completely undermine the security of the AEAD. |
| 59 | * Nonces may be predictable and public, so long as they are unique. Uniqueness |
| 60 | * may be achieved with a simple counter or, if large enough, may be generated |
| 61 | * randomly. The nonce must be passed into the "open" operation by the receiver |
| 62 | * so must either be implicit (e.g. a counter), or must be transmitted along |
| 63 | * with the sealed message. |
| 64 | * |
| 65 | * The "seal" and "open" operations are atomic - an entire message must be |
| 66 | * encrypted or decrypted in a single call. Large messages may have to be split |
Steven Valdez | b0b45c6 | 2017-01-17 16:23:54 -0500 | [diff] [blame] | 67 | * up in order to accommodate this. When doing so, be mindful of the need not to |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 68 | * repeat nonces and the possibility that an attacker could duplicate, reorder |
| 69 | * or drop message chunks. For example, using a single key for a given (large) |
| 70 | * message and sealing chunks with nonces counting from zero would be secure as |
| 71 | * long as the number of chunks was securely transmitted. (Otherwise an |
| 72 | * attacker could truncate the message by dropping chunks from the end.) |
| 73 | * |
| 74 | * The number of chunks could be transmitted by prefixing it to the plaintext, |
| 75 | * for example. This also assumes that no other message would ever use the same |
| 76 | * key otherwise the rule that nonces must be unique for a given key would be |
| 77 | * violated. |
| 78 | * |
| 79 | * The "seal" and "open" operations also permit additional data to be |
| 80 | * authenticated via the |ad| parameter. This data is not included in the |
| 81 | * ciphertext and must be identical for both the "seal" and "open" call. This |
| 82 | * permits implicit context to be authenticated but may be empty if not needed. |
| 83 | * |
| 84 | * The "seal" and "open" operations may work in-place if the |out| and |in| |
David Benjamin | f0c4a6c | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 85 | * arguments are equal. Otherwise, if |out| and |in| alias, input data may be |
| 86 | * overwritten before it is read. This situation will cause an error. |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 87 | * |
| 88 | * The "seal" and "open" operations return one on success and zero on error. */ |
| 89 | |
| 90 | |
| 91 | /* AEAD algorithms. */ |
| 92 | |
| 93 | /* EVP_aead_aes_128_gcm is AES-128 in Galois Counter Mode. */ |
| 94 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_128_gcm(void); |
| 95 | |
| 96 | /* EVP_aead_aes_256_gcm is AES-256 in Galois Counter Mode. */ |
| 97 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_256_gcm(void); |
| 98 | |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame] | 99 | /* EVP_aead_chacha20_poly1305 is the AEAD built from ChaCha20 and |
| 100 | * Poly1305 as described in RFC 7539. */ |
| 101 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_chacha20_poly1305(void); |
| 102 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 103 | /* EVP_aead_aes_128_ctr_hmac_sha256 is AES-128 in CTR mode with HMAC-SHA256 for |
| 104 | * authentication. The nonce is 12 bytes; the bottom 32-bits are used as the |
| 105 | * block counter, thus the maximum plaintext size is 64GB. */ |
| 106 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_128_ctr_hmac_sha256(void); |
| 107 | |
Adam Langley | fad6327 | 2015-11-12 12:15:39 -0800 | [diff] [blame] | 108 | /* EVP_aead_aes_256_ctr_hmac_sha256 is AES-256 in CTR mode with HMAC-SHA256 for |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 109 | * authentication. See |EVP_aead_aes_128_ctr_hmac_sha256| for details. */ |
| 110 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_256_ctr_hmac_sha256(void); |
| 111 | |
David Benjamin | 1b24967 | 2016-12-06 18:25:50 -0500 | [diff] [blame] | 112 | /* EVP_aead_aes_128_gcm_siv is AES-128 in GCM-SIV mode. See |
| 113 | * https://tools.ietf.org/html/draft-irtf-cfrg-gcmsiv-02 */ |
| 114 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_128_gcm_siv(void); |
| 115 | |
| 116 | /* EVP_aead_aes_256_gcm_siv is AES-256 in GCM-SIV mode. See |
| 117 | * https://tools.ietf.org/html/draft-irtf-cfrg-gcmsiv-02 */ |
| 118 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_256_gcm_siv(void); |
| 119 | |
Robert Sloan | 9254e68 | 2017-04-24 09:42:06 -0700 | [diff] [blame] | 120 | /* EVP_aead_aes_128_gcm_fips_testonly is AES-128 in Galois Counter Mode with |
| 121 | * an internally-generated random nonce. This is unsafe and should not be |
| 122 | * used. */ |
| 123 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_128_gcm_fips_testonly(void); |
| 124 | |
| 125 | /* EVP_aead_aes_256_gcm_fips_testonly is AES-256 in Galois Counter Mode with |
| 126 | * an internally-generated random nonce. This is unsafe and should not be |
| 127 | * used. */ |
| 128 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_256_gcm_fips_testonly(void); |
| 129 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 130 | /* EVP_has_aes_hardware returns one if we enable hardware support for fast and |
| 131 | * constant-time AES-GCM. */ |
| 132 | OPENSSL_EXPORT int EVP_has_aes_hardware(void); |
| 133 | |
| 134 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 135 | /* Utility functions. */ |
| 136 | |
| 137 | /* EVP_AEAD_key_length returns the length, in bytes, of the keys used by |
| 138 | * |aead|. */ |
| 139 | OPENSSL_EXPORT size_t EVP_AEAD_key_length(const EVP_AEAD *aead); |
| 140 | |
| 141 | /* EVP_AEAD_nonce_length returns the length, in bytes, of the per-message nonce |
| 142 | * for |aead|. */ |
| 143 | OPENSSL_EXPORT size_t EVP_AEAD_nonce_length(const EVP_AEAD *aead); |
| 144 | |
| 145 | /* EVP_AEAD_max_overhead returns the maximum number of additional bytes added |
| 146 | * by the act of sealing data with |aead|. */ |
| 147 | OPENSSL_EXPORT size_t EVP_AEAD_max_overhead(const EVP_AEAD *aead); |
| 148 | |
| 149 | /* EVP_AEAD_max_tag_len returns the maximum tag length when using |aead|. This |
| 150 | * is the largest value that can be passed as |tag_len| to |
| 151 | * |EVP_AEAD_CTX_init|. */ |
| 152 | OPENSSL_EXPORT size_t EVP_AEAD_max_tag_len(const EVP_AEAD *aead); |
| 153 | |
| 154 | |
| 155 | /* AEAD operations. */ |
| 156 | |
| 157 | /* An EVP_AEAD_CTX represents an AEAD algorithm configured with a specific key |
| 158 | * and message-independent IV. */ |
| 159 | typedef struct evp_aead_ctx_st { |
| 160 | const EVP_AEAD *aead; |
| 161 | /* aead_state is an opaque pointer to whatever state the AEAD needs to |
| 162 | * maintain. */ |
| 163 | void *aead_state; |
| 164 | } EVP_AEAD_CTX; |
| 165 | |
| 166 | /* EVP_AEAD_MAX_KEY_LENGTH contains the maximum key length used by |
| 167 | * any AEAD defined in this header. */ |
| 168 | #define EVP_AEAD_MAX_KEY_LENGTH 80 |
| 169 | |
| 170 | /* EVP_AEAD_MAX_NONCE_LENGTH contains the maximum nonce length used by |
| 171 | * any AEAD defined in this header. */ |
| 172 | #define EVP_AEAD_MAX_NONCE_LENGTH 16 |
| 173 | |
| 174 | /* EVP_AEAD_MAX_OVERHEAD contains the maximum overhead used by any AEAD |
| 175 | * defined in this header. */ |
| 176 | #define EVP_AEAD_MAX_OVERHEAD 64 |
| 177 | |
| 178 | /* EVP_AEAD_DEFAULT_TAG_LENGTH is a magic value that can be passed to |
| 179 | * EVP_AEAD_CTX_init to indicate that the default tag length for an AEAD should |
| 180 | * be used. */ |
| 181 | #define EVP_AEAD_DEFAULT_TAG_LENGTH 0 |
| 182 | |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 183 | /* EVP_AEAD_CTX_zero sets an uninitialized |ctx| to the zero state. It must be |
| 184 | * initialized with |EVP_AEAD_CTX_init| before use. It is safe, but not |
| 185 | * necessary, to call |EVP_AEAD_CTX_cleanup| in this state. This may be used for |
| 186 | * more uniform cleanup of |EVP_AEAD_CTX|. */ |
| 187 | OPENSSL_EXPORT void EVP_AEAD_CTX_zero(EVP_AEAD_CTX *ctx); |
| 188 | |
| 189 | /* EVP_AEAD_CTX_init initializes |ctx| for the given AEAD algorithm. The |impl| |
| 190 | * argument is ignored and should be NULL. Authentication tags may be truncated |
| 191 | * by passing a size as |tag_len|. A |tag_len| of zero indicates the default |
| 192 | * tag length and this is defined as EVP_AEAD_DEFAULT_TAG_LENGTH for |
| 193 | * readability. |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 194 | * |
| 195 | * Returns 1 on success. Otherwise returns 0 and pushes to the error stack. In |
| 196 | * the error case, you do not need to call |EVP_AEAD_CTX_cleanup|, but it's |
| 197 | * harmless to do so. */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 198 | OPENSSL_EXPORT int EVP_AEAD_CTX_init(EVP_AEAD_CTX *ctx, const EVP_AEAD *aead, |
| 199 | const uint8_t *key, size_t key_len, |
| 200 | size_t tag_len, ENGINE *impl); |
| 201 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 202 | /* EVP_AEAD_CTX_cleanup frees any data allocated by |ctx|. It is a no-op to |
| 203 | * call |EVP_AEAD_CTX_cleanup| on a |EVP_AEAD_CTX| that has been |memset| to |
| 204 | * all zeros. */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 205 | OPENSSL_EXPORT void EVP_AEAD_CTX_cleanup(EVP_AEAD_CTX *ctx); |
| 206 | |
| 207 | /* EVP_AEAD_CTX_seal encrypts and authenticates |in_len| bytes from |in| and |
| 208 | * authenticates |ad_len| bytes from |ad| and writes the result to |out|. It |
| 209 | * returns one on success and zero otherwise. |
| 210 | * |
| 211 | * This function may be called (with the same |EVP_AEAD_CTX|) concurrently with |
| 212 | * itself or |EVP_AEAD_CTX_open|. |
| 213 | * |
| 214 | * At most |max_out_len| bytes are written to |out| and, in order to ensure |
| 215 | * success, |max_out_len| should be |in_len| plus the result of |
Kenny Root | b3106a0 | 2015-05-08 13:38:31 -0700 | [diff] [blame] | 216 | * |EVP_AEAD_max_overhead|. On successful return, |*out_len| is set to the |
| 217 | * actual number of bytes written. |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 218 | * |
| 219 | * The length of |nonce|, |nonce_len|, must be equal to the result of |
| 220 | * |EVP_AEAD_nonce_length| for this AEAD. |
| 221 | * |
| 222 | * |EVP_AEAD_CTX_seal| never results in a partial output. If |max_out_len| is |
| 223 | * insufficient, zero will be returned. (In this case, |*out_len| is set to |
| 224 | * zero.) |
| 225 | * |
David Benjamin | 6e899c7 | 2016-06-09 18:02:18 -0400 | [diff] [blame] | 226 | * If |in| and |out| alias then |out| must be == |in|. */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 227 | OPENSSL_EXPORT int EVP_AEAD_CTX_seal(const EVP_AEAD_CTX *ctx, uint8_t *out, |
| 228 | size_t *out_len, size_t max_out_len, |
| 229 | const uint8_t *nonce, size_t nonce_len, |
| 230 | const uint8_t *in, size_t in_len, |
| 231 | const uint8_t *ad, size_t ad_len); |
| 232 | |
| 233 | /* EVP_AEAD_CTX_open authenticates |in_len| bytes from |in| and |ad_len| bytes |
| 234 | * from |ad| and decrypts at most |in_len| bytes into |out|. It returns one on |
| 235 | * success and zero otherwise. |
| 236 | * |
| 237 | * This function may be called (with the same |EVP_AEAD_CTX|) concurrently with |
| 238 | * itself or |EVP_AEAD_CTX_seal|. |
| 239 | * |
| 240 | * At most |in_len| bytes are written to |out|. In order to ensure success, |
| 241 | * |max_out_len| should be at least |in_len|. On successful return, |*out_len| |
| 242 | * is set to the the actual number of bytes written. |
| 243 | * |
| 244 | * The length of |nonce|, |nonce_len|, must be equal to the result of |
| 245 | * |EVP_AEAD_nonce_length| for this AEAD. |
| 246 | * |
| 247 | * |EVP_AEAD_CTX_open| never results in a partial output. If |max_out_len| is |
| 248 | * insufficient, zero will be returned. (In this case, |*out_len| is set to |
| 249 | * zero.) |
| 250 | * |
David Benjamin | 6e899c7 | 2016-06-09 18:02:18 -0400 | [diff] [blame] | 251 | * If |in| and |out| alias then |out| must be == |in|. */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 252 | OPENSSL_EXPORT int EVP_AEAD_CTX_open(const EVP_AEAD_CTX *ctx, uint8_t *out, |
| 253 | size_t *out_len, size_t max_out_len, |
| 254 | const uint8_t *nonce, size_t nonce_len, |
| 255 | const uint8_t *in, size_t in_len, |
| 256 | const uint8_t *ad, size_t ad_len); |
| 257 | |
David Benjamin | 7c0d06c | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 258 | /* EVP_AEAD_CTX_aead returns the underlying AEAD for |ctx|, or NULL if one has |
| 259 | * not been set. */ |
| 260 | OPENSSL_EXPORT const EVP_AEAD *EVP_AEAD_CTX_aead(const EVP_AEAD_CTX *ctx); |
| 261 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 262 | |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 263 | /* TLS-specific AEAD algorithms. |
| 264 | * |
| 265 | * These AEAD primitives do not meet the definition of generic AEADs. They are |
| 266 | * all specific to TLS and should not be used outside of that context. They must |
| 267 | * be initialized with |EVP_AEAD_CTX_init_with_direction|, are stateful, and may |
| 268 | * not be used concurrently. Any nonces are used as IVs, so they must be |
| 269 | * unpredictable. They only accept an |ad| parameter of length 11 (the standard |
| 270 | * TLS one with length omitted). */ |
| 271 | |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 272 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_128_cbc_sha1_tls(void); |
| 273 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_128_cbc_sha1_tls_implicit_iv(void); |
| 274 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_128_cbc_sha256_tls(void); |
| 275 | |
| 276 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_256_cbc_sha1_tls(void); |
| 277 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_256_cbc_sha1_tls_implicit_iv(void); |
| 278 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_256_cbc_sha256_tls(void); |
| 279 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_256_cbc_sha384_tls(void); |
| 280 | |
| 281 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_des_ede3_cbc_sha1_tls(void); |
| 282 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_des_ede3_cbc_sha1_tls_implicit_iv(void); |
| 283 | |
| 284 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_null_sha1_tls(void); |
| 285 | |
| 286 | |
| 287 | /* SSLv3-specific AEAD algorithms. |
| 288 | * |
| 289 | * These AEAD primitives do not meet the definition of generic AEADs. They are |
| 290 | * all specific to SSLv3 and should not be used outside of that context. They |
| 291 | * must be initialized with |EVP_AEAD_CTX_init_with_direction|, are stateful, |
| 292 | * and may not be used concurrently. They only accept an |ad| parameter of |
| 293 | * length 9 (the standard TLS one with length and version omitted). */ |
| 294 | |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 295 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_128_cbc_sha1_ssl3(void); |
| 296 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_256_cbc_sha1_ssl3(void); |
| 297 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_des_ede3_cbc_sha1_ssl3(void); |
| 298 | OPENSSL_EXPORT const EVP_AEAD *EVP_aead_null_sha1_ssl3(void); |
| 299 | |
| 300 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 301 | /* Obscure functions. */ |
| 302 | |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 303 | /* evp_aead_direction_t denotes the direction of an AEAD operation. */ |
| 304 | enum evp_aead_direction_t { |
| 305 | evp_aead_open, |
| 306 | evp_aead_seal, |
| 307 | }; |
| 308 | |
| 309 | /* EVP_AEAD_CTX_init_with_direction calls |EVP_AEAD_CTX_init| for normal |
| 310 | * AEADs. For TLS-specific and SSL3-specific AEADs, it initializes |ctx| for a |
| 311 | * given direction. */ |
| 312 | OPENSSL_EXPORT int EVP_AEAD_CTX_init_with_direction( |
| 313 | EVP_AEAD_CTX *ctx, const EVP_AEAD *aead, const uint8_t *key, size_t key_len, |
| 314 | size_t tag_len, enum evp_aead_direction_t dir); |
| 315 | |
Adam Langley | fad6327 | 2015-11-12 12:15:39 -0800 | [diff] [blame] | 316 | /* EVP_AEAD_CTX_get_iv sets |*out_len| to the length of the IV for |ctx| and |
| 317 | * sets |*out_iv| to point to that many bytes of the current IV. This is only |
| 318 | * meaningful for AEADs with implicit IVs (i.e. CBC mode in SSLv3 and TLS 1.0). |
| 319 | * |
| 320 | * It returns one on success or zero on error. */ |
| 321 | OPENSSL_EXPORT int EVP_AEAD_CTX_get_iv(const EVP_AEAD_CTX *ctx, |
| 322 | const uint8_t **out_iv, size_t *out_len); |
| 323 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 324 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 325 | #if defined(__cplusplus) |
| 326 | } /* extern C */ |
David Benjamin | f0c4a6c | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 327 | |
| 328 | #if !defined(BORINGSSL_NO_CXX) |
| 329 | extern "C++" { |
| 330 | |
| 331 | namespace bssl { |
| 332 | |
| 333 | using ScopedEVP_AEAD_CTX = |
| 334 | internal::StackAllocated<EVP_AEAD_CTX, void, EVP_AEAD_CTX_zero, |
| 335 | EVP_AEAD_CTX_cleanup>; |
| 336 | |
| 337 | } // namespace bssl |
| 338 | |
| 339 | } // extern C++ |
| 340 | #endif |
| 341 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 342 | #endif |
| 343 | |
| 344 | #endif /* OPENSSL_HEADER_AEAD_H */ |