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_INTERNAL_H
58 #define OPENSSL_HEADER_CIPHER_INTERNAL_H
59 
60 #include <openssl/base.h>
61 
62 #include <openssl/aead.h>
63 
64 #if defined(__cplusplus)
65 extern "C" {
66 #endif
67 
68 
69 /* EVP_CIPH_MODE_MASK contains the bits of |flags| that represent the mode. */
70 #define EVP_CIPH_MODE_MASK 0x3f
71 
72 
73 /* EVP_AEAD represents a specific AEAD algorithm. */
74 struct evp_aead_st {
75   uint8_t key_len;
76   uint8_t nonce_len;
77   uint8_t overhead;
78   uint8_t max_tag_len;
79 
80   /* init initialises an |EVP_AEAD_CTX|. If this call returns zero then
81    * |cleanup| will not be called for that context. */
82   int (*init)(EVP_AEAD_CTX *, const uint8_t *key, size_t key_len,
83               size_t tag_len);
84   int (*init_with_direction)(EVP_AEAD_CTX *, const uint8_t *key, size_t key_len,
85                              size_t tag_len, enum evp_aead_direction_t dir);
86   void (*cleanup)(EVP_AEAD_CTX *);
87 
88   int (*seal)(const EVP_AEAD_CTX *ctx, uint8_t *out, size_t *out_len,
89               size_t max_out_len, const uint8_t *nonce, size_t nonce_len,
90               const uint8_t *in, size_t in_len, const uint8_t *ad,
91               size_t ad_len);
92 
93   int (*open)(const EVP_AEAD_CTX *ctx, uint8_t *out, size_t *out_len,
94               size_t max_out_len, const uint8_t *nonce, size_t nonce_len,
95               const uint8_t *in, size_t in_len, const uint8_t *ad,
96               size_t ad_len);
97 
98   int (*get_rc4_state)(const EVP_AEAD_CTX *ctx, const RC4_KEY **out_key);
99 };
100 
101 
102 /* EVP_tls_cbc_get_padding determines the padding from the decrypted, TLS, CBC
103  * record in |in|. This decrypted record should not include any "decrypted"
104  * explicit IV. It sets |*out_len| to the length with the padding removed or
105  * |in_len| if invalid.
106  *
107  * block_size: the block size of the cipher used to encrypt the record.
108  * returns:
109  *   0: (in non-constant time) if the record is publicly invalid.
110  *   1: if the padding was valid
111  *  -1: otherwise. */
112 int EVP_tls_cbc_remove_padding(unsigned *out_len,
113                                const uint8_t *in, unsigned in_len,
114                                unsigned block_size, unsigned mac_size);
115 
116 /* EVP_tls_cbc_copy_mac copies |md_size| bytes from the end of the first
117  * |in_len| bytes of |in| to |out| in constant time (independent of the concrete
118  * value of |in_len|, which may vary within a 256-byte window). |in| must point
119  * to a buffer of |orig_len| bytes.
120  *
121  * On entry:
122  *   orig_len >= in_len >= md_size
123  *   md_size <= EVP_MAX_MD_SIZE */
124 void EVP_tls_cbc_copy_mac(uint8_t *out, unsigned md_size,
125                           const uint8_t *in, unsigned in_len,
126                           unsigned orig_len);
127 
128 /* EVP_tls_cbc_record_digest_supported returns 1 iff |md| is a hash function
129  * which EVP_tls_cbc_digest_record supports. */
130 int EVP_tls_cbc_record_digest_supported(const EVP_MD *md);
131 
132 /* EVP_tls_cbc_digest_record computes the MAC of a decrypted, padded TLS
133  * record.
134  *
135  *   md: the hash function used in the HMAC.
136  *     EVP_tls_cbc_record_digest_supported must return true for this hash.
137  *   md_out: the digest output. At most EVP_MAX_MD_SIZE bytes will be written.
138  *   md_out_size: the number of output bytes is written here.
139  *   header: the 13-byte, TLS record header.
140  *   data: the record data itself
141  *   data_plus_mac_size: the secret, reported length of the data and MAC
142  *     once the padding has been removed.
143  *   data_plus_mac_plus_padding_size: the public length of the whole
144  *     record, including padding.
145  *
146  * On entry: by virtue of having been through one of the remove_padding
147  * functions, above, we know that data_plus_mac_size is large enough to contain
148  * a padding byte and MAC. (If the padding was invalid, it might contain the
149  * padding too. ) */
150 int EVP_tls_cbc_digest_record(const EVP_MD *md, uint8_t *md_out,
151                               size_t *md_out_size, const uint8_t header[13],
152                               const uint8_t *data, size_t data_plus_mac_size,
153                               size_t data_plus_mac_plus_padding_size,
154                               const uint8_t *mac_secret,
155                               unsigned mac_secret_length);
156 
157 #if defined(__cplusplus)
158 } /* extern C */
159 #endif
160 
161 #endif /* OPENSSL_HEADER_CIPHER_INTERNAL_H */
162