1/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
2 * All rights reserved.
3 *
4 * This package is an SSL implementation written
5 * by Eric Young (eay@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@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@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@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_EXTRA_INTERNAL_H
58#define OPENSSL_HEADER_CIPHER_EXTRA_INTERNAL_H
59
60#include <openssl/base.h>
61
62#include "../internal.h"
63
64#if defined(__cplusplus)
65extern "C" {
66#endif
67
68
69// EVP_tls_cbc_get_padding determines the padding from the decrypted, TLS, CBC
70// record in |in|. This decrypted record should not include any "decrypted"
71// explicit IV. If the record is publicly invalid, it returns zero. Otherwise,
72// it returns one and sets |*out_padding_ok| to all ones (0xfff..f) if the
73// padding is valid and zero otherwise. It then sets |*out_len| to the length
74// with the padding removed or |in_len| if invalid.
75//
76// If the function returns one, it runs in time independent of the contents of
77// |in|. It is also guaranteed that |*out_len| >= |mac_size|, satisfying
78// |EVP_tls_cbc_copy_mac|'s precondition.
79int EVP_tls_cbc_remove_padding(crypto_word_t *out_padding_ok, size_t *out_len,
80 const uint8_t *in, size_t in_len,
81 size_t block_size, size_t mac_size);
82
83// EVP_tls_cbc_copy_mac copies |md_size| bytes from the end of the first
84// |in_len| bytes of |in| to |out| in constant time (independent of the concrete
85// value of |in_len|, which may vary within a 256-byte window). |in| must point
86// to a buffer of |orig_len| bytes.
87//
88// On entry:
89// orig_len >= in_len >= md_size
90// md_size <= EVP_MAX_MD_SIZE
91void EVP_tls_cbc_copy_mac(uint8_t *out, size_t md_size, const uint8_t *in,
92 size_t in_len, size_t orig_len);
93
94// EVP_tls_cbc_record_digest_supported returns 1 iff |md| is a hash function
95// which EVP_tls_cbc_digest_record supports.
96int EVP_tls_cbc_record_digest_supported(const EVP_MD *md);
97
98// EVP_tls_cbc_digest_record computes the MAC of a decrypted, padded TLS
99// record.
100//
101// md: the hash function used in the HMAC.
102// EVP_tls_cbc_record_digest_supported must return true for this hash.
103// md_out: the digest output. At most EVP_MAX_MD_SIZE bytes will be written.
104// md_out_size: the number of output bytes is written here.
105// header: the 13-byte, TLS record header.
106// data: the record data itself
107// data_plus_mac_size: the secret, reported length of the data and MAC
108// once the padding has been removed.
109// data_plus_mac_plus_padding_size: the public length of the whole
110// record, including padding.
111//
112// On entry: by virtue of having been through one of the remove_padding
113// functions, above, we know that data_plus_mac_size is large enough to contain
114// a padding byte and MAC. (If the padding was invalid, it might contain the
115// padding too. )
116int EVP_tls_cbc_digest_record(const EVP_MD *md, uint8_t *md_out,
117 size_t *md_out_size, const uint8_t header[13],
118 const uint8_t *data, size_t data_plus_mac_size,
119 size_t data_plus_mac_plus_padding_size,
120 const uint8_t *mac_secret,
121 unsigned mac_secret_length);
122
123
124#if defined(__cplusplus)
125} // extern C
126#endif
127
128#endif // OPENSSL_HEADER_CIPHER_EXTRA_INTERNAL_H
129