Home | History | Annotate | Download | only in openssl
      1 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com)
      2  * All rights reserved.
      3  *
      4  * This package is an SSL implementation written
      5  * by Eric Young (eay (at) cryptsoft.com).
      6  * The implementation was written so as to conform with Netscapes SSL.
      7  *
      8  * This library is free for commercial and non-commercial use as long as
      9  * the following conditions are aheared to.  The following conditions
     10  * apply to all code found in this distribution, be it the RC4, RSA,
     11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
     12  * included with this distribution is covered by the same copyright terms
     13  * except that the holder is Tim Hudson (tjh (at) cryptsoft.com).
     14  *
     15  * Copyright remains Eric Young's, and as such any Copyright notices in
     16  * the code are not to be removed.
     17  * If this package is used in a product, Eric Young should be given attribution
     18  * as the author of the parts of the library used.
     19  * This can be in the form of a textual message at program startup or
     20  * in documentation (online or textual) provided with the package.
     21  *
     22  * Redistribution and use in source and binary forms, with or without
     23  * modification, are permitted provided that the following conditions
     24  * are met:
     25  * 1. Redistributions of source code must retain the copyright
     26  *    notice, this list of conditions and the following disclaimer.
     27  * 2. Redistributions in binary form must reproduce the above copyright
     28  *    notice, this list of conditions and the following disclaimer in the
     29  *    documentation and/or other materials provided with the distribution.
     30  * 3. All advertising materials mentioning features or use of this software
     31  *    must display the following acknowledgement:
     32  *    "This product includes cryptographic software written by
     33  *     Eric Young (eay (at) cryptsoft.com)"
     34  *    The word 'cryptographic' can be left out if the rouines from the library
     35  *    being used are not cryptographic related :-).
     36  * 4. If you include any Windows specific code (or a derivative thereof) from
     37  *    the apps directory (application code) you must include an acknowledgement:
     38  *    "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)"
     39  *
     40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
     41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     50  * SUCH DAMAGE.
     51  *
     52  * The licence and distribution terms for any publically available version or
     53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
     54  * copied and put under another distribution licence
     55  * [including the GNU Public Licence.] */
     56 
     57 #ifndef OPENSSL_HEADER_CIPHER_H
     58 #define OPENSSL_HEADER_CIPHER_H
     59 
     60 #include <openssl/base.h>
     61 
     62 #if defined(__cplusplus)
     63 extern "C" {
     64 #endif
     65 
     66 
     67 // Ciphers.
     68 
     69 
     70 // Cipher primitives.
     71 //
     72 // The following functions return |EVP_CIPHER| objects that implement the named
     73 // cipher algorithm.
     74 
     75 OPENSSL_EXPORT const EVP_CIPHER *EVP_rc4(void);
     76 
     77 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_cbc(void);
     78 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_ecb(void);
     79 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_ede(void);
     80 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_ede3(void);
     81 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_ede_cbc(void);
     82 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_ede3_cbc(void);
     83 
     84 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_ecb(void);
     85 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_cbc(void);
     86 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_ctr(void);
     87 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_ofb(void);
     88 
     89 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_ecb(void);
     90 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_cbc(void);
     91 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_ctr(void);
     92 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_ofb(void);
     93 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_xts(void);
     94 
     95 // EVP_enc_null returns a 'cipher' that passes plaintext through as
     96 // ciphertext.
     97 OPENSSL_EXPORT const EVP_CIPHER *EVP_enc_null(void);
     98 
     99 // EVP_rc2_cbc returns a cipher that implements 128-bit RC2 in CBC mode.
    100 OPENSSL_EXPORT const EVP_CIPHER *EVP_rc2_cbc(void);
    101 
    102 // EVP_rc2_40_cbc returns a cipher that implements 40-bit RC2 in CBC mode. This
    103 // is obviously very, very weak and is included only in order to read PKCS#12
    104 // files, which often encrypt the certificate chain using this cipher. It is
    105 // deliberately not exported.
    106 const EVP_CIPHER *EVP_rc2_40_cbc(void);
    107 
    108 // EVP_get_cipherbynid returns the cipher corresponding to the given NID, or
    109 // NULL if no such cipher is known.
    110 OPENSSL_EXPORT const EVP_CIPHER *EVP_get_cipherbynid(int nid);
    111 
    112 
    113 // Cipher context allocation.
    114 //
    115 // An |EVP_CIPHER_CTX| represents the state of an encryption or decryption in
    116 // progress.
    117 
    118 // EVP_CIPHER_CTX_init initialises an, already allocated, |EVP_CIPHER_CTX|.
    119 OPENSSL_EXPORT void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx);
    120 
    121 // EVP_CIPHER_CTX_new allocates a fresh |EVP_CIPHER_CTX|, calls
    122 // |EVP_CIPHER_CTX_init| and returns it, or NULL on allocation failure.
    123 OPENSSL_EXPORT EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void);
    124 
    125 // EVP_CIPHER_CTX_cleanup frees any memory referenced by |ctx|. It returns
    126 // one.
    127 OPENSSL_EXPORT int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *ctx);
    128 
    129 // EVP_CIPHER_CTX_free calls |EVP_CIPHER_CTX_cleanup| on |ctx| and then frees
    130 // |ctx| itself.
    131 OPENSSL_EXPORT void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx);
    132 
    133 // EVP_CIPHER_CTX_copy sets |out| to be a duplicate of the current state of
    134 // |in|. The |out| argument must have been previously initialised.
    135 OPENSSL_EXPORT int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out,
    136                                        const EVP_CIPHER_CTX *in);
    137 
    138 // EVP_CIPHER_CTX_reset calls |EVP_CIPHER_CTX_cleanup| followed by
    139 // |EVP_CIPHER_CTX_init|.
    140 OPENSSL_EXPORT void EVP_CIPHER_CTX_reset(EVP_CIPHER_CTX *ctx);
    141 
    142 
    143 // Cipher context configuration.
    144 
    145 // EVP_CipherInit_ex configures |ctx| for a fresh encryption (or decryption, if
    146 // |enc| is zero) operation using |cipher|. If |ctx| has been previously
    147 // configured with a cipher then |cipher|, |key| and |iv| may be |NULL| and
    148 // |enc| may be -1 to reuse the previous values. The operation will use |key|
    149 // as the key and |iv| as the IV (if any). These should have the correct
    150 // lengths given by |EVP_CIPHER_key_length| and |EVP_CIPHER_iv_length|. It
    151 // returns one on success and zero on error.
    152 OPENSSL_EXPORT int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx,
    153                                      const EVP_CIPHER *cipher, ENGINE *engine,
    154                                      const uint8_t *key, const uint8_t *iv,
    155                                      int enc);
    156 
    157 // EVP_EncryptInit_ex calls |EVP_CipherInit_ex| with |enc| equal to one.
    158 OPENSSL_EXPORT int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,
    159                                       const EVP_CIPHER *cipher, ENGINE *impl,
    160                                       const uint8_t *key, const uint8_t *iv);
    161 
    162 // EVP_DecryptInit_ex calls |EVP_CipherInit_ex| with |enc| equal to zero.
    163 OPENSSL_EXPORT int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx,
    164                                       const EVP_CIPHER *cipher, ENGINE *impl,
    165                                       const uint8_t *key, const uint8_t *iv);
    166 
    167 
    168 // Cipher operations.
    169 
    170 // EVP_EncryptUpdate encrypts |in_len| bytes from |in| to |out|. The number
    171 // of output bytes may be up to |in_len| plus the block length minus one and
    172 // |out| must have sufficient space. The number of bytes actually output is
    173 // written to |*out_len|. It returns one on success and zero otherwise.
    174 OPENSSL_EXPORT int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out,
    175                                      int *out_len, const uint8_t *in,
    176                                      int in_len);
    177 
    178 // EVP_EncryptFinal_ex writes at most a block of ciphertext to |out| and sets
    179 // |*out_len| to the number of bytes written. If padding is enabled (the
    180 // default) then standard padding is applied to create the final block. If
    181 // padding is disabled (with |EVP_CIPHER_CTX_set_padding|) then any partial
    182 // block remaining will cause an error. The function returns one on success and
    183 // zero otherwise.
    184 OPENSSL_EXPORT int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, uint8_t *out,
    185                                        int *out_len);
    186 
    187 // EVP_DecryptUpdate decrypts |in_len| bytes from |in| to |out|. The number of
    188 // output bytes may be up to |in_len| plus the block length minus one and |out|
    189 // must have sufficient space. The number of bytes actually output is written
    190 // to |*out_len|. It returns one on success and zero otherwise.
    191 OPENSSL_EXPORT int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out,
    192                                      int *out_len, const uint8_t *in,
    193                                      int in_len);
    194 
    195 // EVP_DecryptFinal_ex writes at most a block of ciphertext to |out| and sets
    196 // |*out_len| to the number of bytes written. If padding is enabled (the
    197 // default) then padding is removed from the final block.
    198 //
    199 // WARNING: it is unsafe to call this function with unauthenticated
    200 // ciphertext if padding is enabled.
    201 OPENSSL_EXPORT int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out,
    202                                        int *out_len);
    203 
    204 // EVP_Cipher performs a one-shot encryption/decryption operation. No partial
    205 // blocks are maintained between calls. However, any internal cipher state is
    206 // still updated. For CBC-mode ciphers, the IV is updated to the final
    207 // ciphertext block. For stream ciphers, the stream is advanced past the bytes
    208 // used. It returns one on success and zero otherwise, unless |EVP_CIPHER_flags|
    209 // has |EVP_CIPH_FLAG_CUSTOM_CIPHER| set. Then it returns the number of bytes
    210 // written or -1 on error.
    211 //
    212 // WARNING: this differs from the usual return value convention when using
    213 // |EVP_CIPH_FLAG_CUSTOM_CIPHER|.
    214 //
    215 // TODO(davidben): The normal ciphers currently never fail, even if, e.g.,
    216 // |in_len| is not a multiple of the block size for CBC-mode decryption. The
    217 // input just gets rounded up while the output gets truncated. This should
    218 // either be officially documented or fail.
    219 OPENSSL_EXPORT int EVP_Cipher(EVP_CIPHER_CTX *ctx, uint8_t *out,
    220                               const uint8_t *in, size_t in_len);
    221 
    222 // EVP_CipherUpdate calls either |EVP_EncryptUpdate| or |EVP_DecryptUpdate|
    223 // depending on how |ctx| has been setup.
    224 OPENSSL_EXPORT int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out,
    225                                     int *out_len, const uint8_t *in,
    226                                     int in_len);
    227 
    228 // EVP_CipherFinal_ex calls either |EVP_EncryptFinal_ex| or
    229 // |EVP_DecryptFinal_ex| depending on how |ctx| has been setup.
    230 OPENSSL_EXPORT int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, uint8_t *out,
    231                                       int *out_len);
    232 
    233 
    234 // Cipher context accessors.
    235 
    236 // EVP_CIPHER_CTX_cipher returns the |EVP_CIPHER| underlying |ctx|, or NULL if
    237 // none has been set.
    238 OPENSSL_EXPORT const EVP_CIPHER *EVP_CIPHER_CTX_cipher(
    239     const EVP_CIPHER_CTX *ctx);
    240 
    241 // EVP_CIPHER_CTX_nid returns a NID identifying the |EVP_CIPHER| underlying
    242 // |ctx| (e.g. |NID_aes_128_gcm|). It will crash if no cipher has been
    243 // configured.
    244 OPENSSL_EXPORT int EVP_CIPHER_CTX_nid(const EVP_CIPHER_CTX *ctx);
    245 
    246 // EVP_CIPHER_CTX_encrypting returns one if |ctx| is configured for encryption
    247 // and zero otherwise.
    248 OPENSSL_EXPORT int EVP_CIPHER_CTX_encrypting(const EVP_CIPHER_CTX *ctx);
    249 
    250 // EVP_CIPHER_CTX_block_size returns the block size, in bytes, of the cipher
    251 // underlying |ctx|, or one if the cipher is a stream cipher. It will crash if
    252 // no cipher has been configured.
    253 OPENSSL_EXPORT unsigned EVP_CIPHER_CTX_block_size(const EVP_CIPHER_CTX *ctx);
    254 
    255 // EVP_CIPHER_CTX_key_length returns the key size, in bytes, of the cipher
    256 // underlying |ctx| or zero if no cipher has been configured.
    257 OPENSSL_EXPORT unsigned EVP_CIPHER_CTX_key_length(const EVP_CIPHER_CTX *ctx);
    258 
    259 // EVP_CIPHER_CTX_iv_length returns the IV size, in bytes, of the cipher
    260 // underlying |ctx|. It will crash if no cipher has been configured.
    261 OPENSSL_EXPORT unsigned EVP_CIPHER_CTX_iv_length(const EVP_CIPHER_CTX *ctx);
    262 
    263 // EVP_CIPHER_CTX_get_app_data returns the opaque, application data pointer for
    264 // |ctx|, or NULL if none has been set.
    265 OPENSSL_EXPORT void *EVP_CIPHER_CTX_get_app_data(const EVP_CIPHER_CTX *ctx);
    266 
    267 // EVP_CIPHER_CTX_set_app_data sets the opaque, application data pointer for
    268 // |ctx| to |data|.
    269 OPENSSL_EXPORT void EVP_CIPHER_CTX_set_app_data(EVP_CIPHER_CTX *ctx,
    270                                                 void *data);
    271 
    272 // EVP_CIPHER_CTX_flags returns a value which is the OR of zero or more
    273 // |EVP_CIPH_*| flags. It will crash if no cipher has been configured.
    274 OPENSSL_EXPORT uint32_t EVP_CIPHER_CTX_flags(const EVP_CIPHER_CTX *ctx);
    275 
    276 // EVP_CIPHER_CTX_mode returns one of the |EVP_CIPH_*| cipher mode values
    277 // enumerated below. It will crash if no cipher has been configured.
    278 OPENSSL_EXPORT uint32_t EVP_CIPHER_CTX_mode(const EVP_CIPHER_CTX *ctx);
    279 
    280 // EVP_CIPHER_CTX_ctrl is an |ioctl| like function. The |command| argument
    281 // should be one of the |EVP_CTRL_*| values. The |arg| and |ptr| arguments are
    282 // specific to the command in question.
    283 OPENSSL_EXPORT int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int command,
    284                                        int arg, void *ptr);
    285 
    286 // EVP_CIPHER_CTX_set_padding sets whether padding is enabled for |ctx| and
    287 // returns one. Pass a non-zero |pad| to enable padding (the default) or zero
    288 // to disable.
    289 OPENSSL_EXPORT int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad);
    290 
    291 // EVP_CIPHER_CTX_set_key_length sets the key length for |ctx|. This is only
    292 // valid for ciphers that can take a variable length key. It returns one on
    293 // success and zero on error.
    294 OPENSSL_EXPORT int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *ctx,
    295                                                  unsigned key_len);
    296 
    297 
    298 // Cipher accessors.
    299 
    300 // EVP_CIPHER_nid returns a NID identifying |cipher|. (For example,
    301 // |NID_aes_128_gcm|.)
    302 OPENSSL_EXPORT int EVP_CIPHER_nid(const EVP_CIPHER *cipher);
    303 
    304 // EVP_CIPHER_block_size returns the block size, in bytes, for |cipher|, or one
    305 // if |cipher| is a stream cipher.
    306 OPENSSL_EXPORT unsigned EVP_CIPHER_block_size(const EVP_CIPHER *cipher);
    307 
    308 // EVP_CIPHER_key_length returns the key size, in bytes, for |cipher|. If
    309 // |cipher| can take a variable key length then this function returns the
    310 // default key length and |EVP_CIPHER_flags| will return a value with
    311 // |EVP_CIPH_VARIABLE_LENGTH| set.
    312 OPENSSL_EXPORT unsigned EVP_CIPHER_key_length(const EVP_CIPHER *cipher);
    313 
    314 // EVP_CIPHER_iv_length returns the IV size, in bytes, of |cipher|, or zero if
    315 // |cipher| doesn't take an IV.
    316 OPENSSL_EXPORT unsigned EVP_CIPHER_iv_length(const EVP_CIPHER *cipher);
    317 
    318 // EVP_CIPHER_flags returns a value which is the OR of zero or more
    319 // |EVP_CIPH_*| flags.
    320 OPENSSL_EXPORT uint32_t EVP_CIPHER_flags(const EVP_CIPHER *cipher);
    321 
    322 // EVP_CIPHER_mode returns one of the cipher mode values enumerated below.
    323 OPENSSL_EXPORT uint32_t EVP_CIPHER_mode(const EVP_CIPHER *cipher);
    324 
    325 
    326 // Key derivation.
    327 
    328 // EVP_BytesToKey generates a key and IV for the cipher |type| by iterating
    329 // |md| |count| times using |data| and |salt|. On entry, the |key| and |iv|
    330 // buffers must have enough space to hold a key and IV for |type|. It returns
    331 // the length of the key on success or zero on error.
    332 OPENSSL_EXPORT int EVP_BytesToKey(const EVP_CIPHER *type, const EVP_MD *md,
    333                                   const uint8_t *salt, const uint8_t *data,
    334                                   size_t data_len, unsigned count, uint8_t *key,
    335                                   uint8_t *iv);
    336 
    337 
    338 // Cipher modes (for |EVP_CIPHER_mode|).
    339 
    340 #define EVP_CIPH_STREAM_CIPHER 0x0
    341 #define EVP_CIPH_ECB_MODE 0x1
    342 #define EVP_CIPH_CBC_MODE 0x2
    343 #define EVP_CIPH_CFB_MODE 0x3
    344 #define EVP_CIPH_OFB_MODE 0x4
    345 #define EVP_CIPH_CTR_MODE 0x5
    346 #define EVP_CIPH_GCM_MODE 0x6
    347 #define EVP_CIPH_XTS_MODE 0x7
    348 
    349 
    350 // Cipher flags (for |EVP_CIPHER_flags|).
    351 
    352 // EVP_CIPH_VARIABLE_LENGTH indicates that the cipher takes a variable length
    353 // key.
    354 #define EVP_CIPH_VARIABLE_LENGTH 0x40
    355 
    356 // EVP_CIPH_ALWAYS_CALL_INIT indicates that the |init| function for the cipher
    357 // should always be called when initialising a new operation, even if the key
    358 // is NULL to indicate that the same key is being used.
    359 #define EVP_CIPH_ALWAYS_CALL_INIT 0x80
    360 
    361 // EVP_CIPH_CUSTOM_IV indicates that the cipher manages the IV itself rather
    362 // than keeping it in the |iv| member of |EVP_CIPHER_CTX|.
    363 #define EVP_CIPH_CUSTOM_IV 0x100
    364 
    365 // EVP_CIPH_CTRL_INIT indicates that EVP_CTRL_INIT should be used when
    366 // initialising an |EVP_CIPHER_CTX|.
    367 #define EVP_CIPH_CTRL_INIT 0x200
    368 
    369 // EVP_CIPH_FLAG_CUSTOM_CIPHER indicates that the cipher manages blocking
    370 // itself. This causes EVP_(En|De)crypt_ex to be simple wrapper functions.
    371 #define EVP_CIPH_FLAG_CUSTOM_CIPHER 0x400
    372 
    373 // EVP_CIPH_FLAG_AEAD_CIPHER specifies that the cipher is an AEAD. This is an
    374 // older version of the proper AEAD interface. See aead.h for the current
    375 // one.
    376 #define EVP_CIPH_FLAG_AEAD_CIPHER 0x800
    377 
    378 // EVP_CIPH_CUSTOM_COPY indicates that the |ctrl| callback should be called
    379 // with |EVP_CTRL_COPY| at the end of normal |EVP_CIPHER_CTX_copy|
    380 // processing.
    381 #define EVP_CIPH_CUSTOM_COPY 0x1000
    382 
    383 
    384 // Deprecated functions
    385 
    386 // EVP_CipherInit acts like EVP_CipherInit_ex except that |EVP_CIPHER_CTX_init|
    387 // is called on |cipher| first, if |cipher| is not NULL.
    388 OPENSSL_EXPORT int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
    389                                   const uint8_t *key, const uint8_t *iv,
    390                                   int enc);
    391 
    392 // EVP_EncryptInit calls |EVP_CipherInit| with |enc| equal to one.
    393 OPENSSL_EXPORT int EVP_EncryptInit(EVP_CIPHER_CTX *ctx,
    394                                    const EVP_CIPHER *cipher, const uint8_t *key,
    395                                    const uint8_t *iv);
    396 
    397 // EVP_DecryptInit calls |EVP_CipherInit| with |enc| equal to zero.
    398 OPENSSL_EXPORT int EVP_DecryptInit(EVP_CIPHER_CTX *ctx,
    399                                    const EVP_CIPHER *cipher, const uint8_t *key,
    400                                    const uint8_t *iv);
    401 
    402 // EVP_add_cipher_alias does nothing and returns one.
    403 OPENSSL_EXPORT int EVP_add_cipher_alias(const char *a, const char *b);
    404 
    405 // EVP_get_cipherbyname returns an |EVP_CIPHER| given a human readable name in
    406 // |name|, or NULL if the name is unknown.
    407 OPENSSL_EXPORT const EVP_CIPHER *EVP_get_cipherbyname(const char *name);
    408 
    409 // These AEADs are deprecated AES-GCM implementations that set
    410 // |EVP_CIPH_FLAG_CUSTOM_CIPHER|. Use |EVP_aead_aes_128_gcm| and
    411 // |EVP_aead_aes_256_gcm| instead.
    412 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_gcm(void);
    413 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_gcm(void);
    414 
    415 // These are deprecated, 192-bit version of AES.
    416 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_192_ecb(void);
    417 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_192_cbc(void);
    418 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_192_ctr(void);
    419 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_192_gcm(void);
    420 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_192_ofb(void);
    421 
    422 // EVP_des_ede3_ecb is an alias for |EVP_des_ede3|. Use the former instead.
    423 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_ede3_ecb(void);
    424 
    425 // EVP_aes_128_cfb128 is only available in decrepit.
    426 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_cfb128(void);
    427 
    428 // EVP_bf_ecb is Blowfish in ECB mode and is only available in decrepit.
    429 OPENSSL_EXPORT const EVP_CIPHER *EVP_bf_ecb(void);
    430 
    431 // EVP_bf_cbc is Blowfish in CBC mode and is only available in decrepit.
    432 OPENSSL_EXPORT const EVP_CIPHER *EVP_bf_cbc(void);
    433 
    434 // EVP_bf_cfb is Blowfish in 64-bit CFB mode and is only available in decrepit.
    435 OPENSSL_EXPORT const EVP_CIPHER *EVP_bf_cfb(void);
    436 
    437 // EVP_cast5_ecb is CAST5 in ECB mode and is only available in decrepit.
    438 OPENSSL_EXPORT const EVP_CIPHER *EVP_cast5_ecb(void);
    439 
    440 // EVP_cast5_cbc is CAST5 in CBC mode and is only available in decrepit.
    441 OPENSSL_EXPORT const EVP_CIPHER *EVP_cast5_cbc(void);
    442 
    443 // The following flags do nothing and are included only to make it easier to
    444 // compile code with BoringSSL.
    445 #define EVP_CIPH_CCM_MODE (-1)
    446 #define EVP_CIPH_OCB_MODE (-2)
    447 #define EVP_CIPH_WRAP_MODE (-3)
    448 #define EVP_CIPHER_CTX_FLAG_WRAP_ALLOW 0
    449 
    450 // EVP_CIPHER_CTX_set_flags does nothing.
    451 OPENSSL_EXPORT void EVP_CIPHER_CTX_set_flags(const EVP_CIPHER_CTX *ctx,
    452                                              uint32_t flags);
    453 
    454 
    455 // Private functions.
    456 
    457 // EVP_CIPH_NO_PADDING disables padding in block ciphers.
    458 #define EVP_CIPH_NO_PADDING 0x800
    459 
    460 // The following are |EVP_CIPHER_CTX_ctrl| commands.
    461 #define EVP_CTRL_INIT 0x0
    462 #define EVP_CTRL_SET_KEY_LENGTH 0x1
    463 #define EVP_CTRL_GET_RC2_KEY_BITS 0x2
    464 #define EVP_CTRL_SET_RC2_KEY_BITS 0x3
    465 #define EVP_CTRL_GET_RC5_ROUNDS 0x4
    466 #define EVP_CTRL_SET_RC5_ROUNDS 0x5
    467 #define EVP_CTRL_RAND_KEY 0x6
    468 #define EVP_CTRL_PBE_PRF_NID 0x7
    469 #define EVP_CTRL_COPY 0x8
    470 #define EVP_CTRL_AEAD_SET_IVLEN 0x9
    471 #define EVP_CTRL_AEAD_GET_TAG 0x10
    472 #define EVP_CTRL_AEAD_SET_TAG 0x11
    473 #define EVP_CTRL_AEAD_SET_IV_FIXED 0x12
    474 #define EVP_CTRL_GCM_IV_GEN 0x13
    475 #define EVP_CTRL_AEAD_SET_MAC_KEY 0x17
    476 // EVP_CTRL_GCM_SET_IV_INV sets the GCM invocation field, decrypt only
    477 #define EVP_CTRL_GCM_SET_IV_INV 0x18
    478 
    479 // The following constants are unused.
    480 #define EVP_GCM_TLS_FIXED_IV_LEN 4
    481 #define EVP_GCM_TLS_EXPLICIT_IV_LEN 8
    482 #define EVP_GCM_TLS_TAG_LEN 16
    483 
    484 // The following are legacy aliases for AEAD |EVP_CIPHER_CTX_ctrl| values.
    485 #define EVP_CTRL_GCM_SET_IVLEN EVP_CTRL_AEAD_SET_IVLEN
    486 #define EVP_CTRL_GCM_GET_TAG EVP_CTRL_AEAD_GET_TAG
    487 #define EVP_CTRL_GCM_SET_TAG EVP_CTRL_AEAD_SET_TAG
    488 #define EVP_CTRL_GCM_SET_IV_FIXED EVP_CTRL_AEAD_SET_IV_FIXED
    489 
    490 #define EVP_MAX_KEY_LENGTH 64
    491 #define EVP_MAX_IV_LENGTH 16
    492 #define EVP_MAX_BLOCK_LENGTH 32
    493 
    494 struct evp_cipher_ctx_st {
    495   // cipher contains the underlying cipher for this context.
    496   const EVP_CIPHER *cipher;
    497 
    498   // app_data is a pointer to opaque, user data.
    499   void *app_data;      // application stuff
    500 
    501   // cipher_data points to the |cipher| specific state.
    502   void *cipher_data;
    503 
    504   // key_len contains the length of the key, which may differ from
    505   // |cipher->key_len| if the cipher can take a variable key length.
    506   unsigned key_len;
    507 
    508   // encrypt is one if encrypting and zero if decrypting.
    509   int encrypt;
    510 
    511   // flags contains the OR of zero or more |EVP_CIPH_*| flags, above.
    512   uint32_t flags;
    513 
    514   // oiv contains the original IV value.
    515   uint8_t oiv[EVP_MAX_IV_LENGTH];
    516 
    517   // iv contains the current IV value, which may have been updated.
    518   uint8_t iv[EVP_MAX_IV_LENGTH];
    519 
    520   // buf contains a partial block which is used by, for example, CTR mode to
    521   // store unused keystream bytes.
    522   uint8_t buf[EVP_MAX_BLOCK_LENGTH];
    523 
    524   // buf_len contains the number of bytes of a partial block contained in
    525   // |buf|.
    526   int buf_len;
    527 
    528   // num contains the number of bytes of |iv| which are valid for modes that
    529   // manage partial blocks themselves.
    530   unsigned num;
    531 
    532   // final_used is non-zero if the |final| buffer contains plaintext.
    533   int final_used;
    534 
    535   // block_mask contains |cipher->block_size| minus one. (The block size
    536   // assumed to be a power of two.)
    537   int block_mask;
    538 
    539   uint8_t final[EVP_MAX_BLOCK_LENGTH];  // possible final block
    540 } /* EVP_CIPHER_CTX */;
    541 
    542 typedef struct evp_cipher_info_st {
    543   const EVP_CIPHER *cipher;
    544   unsigned char iv[EVP_MAX_IV_LENGTH];
    545 } EVP_CIPHER_INFO;
    546 
    547 struct evp_cipher_st {
    548   // type contains a NID identifing the cipher. (e.g. NID_aes_128_gcm.)
    549   int nid;
    550 
    551   // block_size contains the block size, in bytes, of the cipher, or 1 for a
    552   // stream cipher.
    553   unsigned block_size;
    554 
    555   // key_len contains the key size, in bytes, for the cipher. If the cipher
    556   // takes a variable key size then this contains the default size.
    557   unsigned key_len;
    558 
    559   // iv_len contains the IV size, in bytes, or zero if inapplicable.
    560   unsigned iv_len;
    561 
    562   // ctx_size contains the size, in bytes, of the per-key context for this
    563   // cipher.
    564   unsigned ctx_size;
    565 
    566   // flags contains the OR of a number of flags. See |EVP_CIPH_*|.
    567   uint32_t flags;
    568 
    569   // app_data is a pointer to opaque, user data.
    570   void *app_data;
    571 
    572   int (*init)(EVP_CIPHER_CTX *ctx, const uint8_t *key, const uint8_t *iv,
    573               int enc);
    574 
    575   int (*cipher)(EVP_CIPHER_CTX *ctx, uint8_t *out, const uint8_t *in,
    576                 size_t inl);
    577 
    578   // cleanup, if non-NULL, releases memory associated with the context. It is
    579   // called if |EVP_CTRL_INIT| succeeds. Note that |init| may not have been
    580   // called at this point.
    581   void (*cleanup)(EVP_CIPHER_CTX *);
    582 
    583   int (*ctrl)(EVP_CIPHER_CTX *, int type, int arg, void *ptr);
    584 };
    585 
    586 
    587 #if defined(__cplusplus)
    588 }  // extern C
    589 
    590 #if !defined(BORINGSSL_NO_CXX)
    591 extern "C++" {
    592 
    593 BSSL_NAMESPACE_BEGIN
    594 
    595 BORINGSSL_MAKE_DELETER(EVP_CIPHER_CTX, EVP_CIPHER_CTX_free)
    596 
    597 using ScopedEVP_CIPHER_CTX =
    598     internal::StackAllocated<EVP_CIPHER_CTX, int, EVP_CIPHER_CTX_init,
    599                              EVP_CIPHER_CTX_cleanup>;
    600 
    601 BSSL_NAMESPACE_END
    602 
    603 }  // extern C++
    604 #endif
    605 
    606 #endif
    607 
    608 #define CIPHER_R_AES_KEY_SETUP_FAILED 100
    609 #define CIPHER_R_BAD_DECRYPT 101
    610 #define CIPHER_R_BAD_KEY_LENGTH 102
    611 #define CIPHER_R_BUFFER_TOO_SMALL 103
    612 #define CIPHER_R_CTRL_NOT_IMPLEMENTED 104
    613 #define CIPHER_R_CTRL_OPERATION_NOT_IMPLEMENTED 105
    614 #define CIPHER_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH 106
    615 #define CIPHER_R_INITIALIZATION_ERROR 107
    616 #define CIPHER_R_INPUT_NOT_INITIALIZED 108
    617 #define CIPHER_R_INVALID_AD_SIZE 109
    618 #define CIPHER_R_INVALID_KEY_LENGTH 110
    619 #define CIPHER_R_INVALID_NONCE_SIZE 111
    620 #define CIPHER_R_INVALID_OPERATION 112
    621 #define CIPHER_R_IV_TOO_LARGE 113
    622 #define CIPHER_R_NO_CIPHER_SET 114
    623 #define CIPHER_R_OUTPUT_ALIASES_INPUT 115
    624 #define CIPHER_R_TAG_TOO_LARGE 116
    625 #define CIPHER_R_TOO_LARGE 117
    626 #define CIPHER_R_UNSUPPORTED_AD_SIZE 118
    627 #define CIPHER_R_UNSUPPORTED_INPUT_SIZE 119
    628 #define CIPHER_R_UNSUPPORTED_KEY_SIZE 120
    629 #define CIPHER_R_UNSUPPORTED_NONCE_SIZE 121
    630 #define CIPHER_R_UNSUPPORTED_TAG_SIZE 122
    631 #define CIPHER_R_WRONG_FINAL_BLOCK_LENGTH 123
    632 #define CIPHER_R_NO_DIRECTION_SET 124
    633 #define CIPHER_R_INVALID_NONCE 125
    634 
    635 #endif  // OPENSSL_HEADER_CIPHER_H
    636