/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.] */
#ifndef OPENSSL_HEADER_CIPHER_EXTRA_INTERNAL_H
#define OPENSSL_HEADER_CIPHER_EXTRA_INTERNAL_H
#include <openssl/base.h>
#include "../internal.h"
#if defined(__cplusplus)
extern "C" {
#endif
// EVP_tls_cbc_get_padding determines the padding from the decrypted, TLS, CBC
// record in |in|. This decrypted record should not include any "decrypted"
// explicit IV. If the record is publicly invalid, it returns zero. Otherwise,
// it returns one and sets |*out_padding_ok| to all ones (0xfff..f) if the
// padding is valid and zero otherwise. It then sets |*out_len| to the length
// with the padding removed or |in_len| if invalid.
//
// If the function returns one, it runs in time independent of the contents of
// |in|. It is also guaranteed that |*out_len| >= |mac_size|, satisfying
// |EVP_tls_cbc_copy_mac|'s precondition.
int EVP_tls_cbc_remove_padding(crypto_word_t *out_padding_ok, size_t *out_len,
const uint8_t *in, size_t in_len,
size_t block_size, size_t mac_size);
// EVP_tls_cbc_copy_mac copies |md_size| bytes from the end of the first
// |in_len| bytes of |in| to |out| in constant time (independent of the concrete
// value of |in_len|, which may vary within a 256-byte window). |in| must point
// to a buffer of |orig_len| bytes.
//
// On entry:
// orig_len >= in_len >= md_size
// md_size <= EVP_MAX_MD_SIZE
void EVP_tls_cbc_copy_mac(uint8_t *out, size_t md_size, const uint8_t *in,
size_t in_len, size_t orig_len);
// EVP_tls_cbc_record_digest_supported returns 1 iff |md| is a hash function
// which EVP_tls_cbc_digest_record supports.
int EVP_tls_cbc_record_digest_supported(const EVP_MD *md);
// EVP_tls_cbc_digest_record computes the MAC of a decrypted, padded TLS
// record.
//
// md: the hash function used in the HMAC.
// EVP_tls_cbc_record_digest_supported must return true for this hash.
// md_out: the digest output. At most EVP_MAX_MD_SIZE bytes will be written.
// md_out_size: the number of output bytes is written here.
// header: the 13-byte, TLS record header.
// data: the record data itself
// data_plus_mac_size: the secret, reported length of the data and MAC
// once the padding has been removed.
// data_plus_mac_plus_padding_size: the public length of the whole
// record, including padding.
//
// On entry: by virtue of having been through one of the remove_padding
// functions, above, we know that data_plus_mac_size is large enough to contain
// a padding byte and MAC. (If the padding was invalid, it might contain the
// padding too. )
int EVP_tls_cbc_digest_record(const EVP_MD *md, uint8_t *md_out,
size_t *md_out_size, const uint8_t header[13],
const uint8_t *data, size_t data_plus_mac_size,
size_t data_plus_mac_plus_padding_size,
const uint8_t *mac_secret,
unsigned mac_secret_length);
#if defined(__cplusplus)
} // extern C
#endif
#endif // OPENSSL_HEADER_CIPHER_EXTRA_INTERNAL_H