1/*
2 * Copyright (c) 2003 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include "config.h"
35
36
37#ifdef KRB5
38#include <krb5-types.h>
39#endif
40
41#include <string.h>
42
43#include "rijndael-alg-fst.h"
44#include "aes.h"
45
46int
47AES_set_encrypt_key(const unsigned char *userkey, const int bits, AES_KEY *key)
48{
49    key->rounds = rijndaelKeySetupEnc(key->key, userkey, bits);
50    if (key->rounds == 0)
51	return -1;
52    return 0;
53}
54
55int
56AES_set_decrypt_key(const unsigned char *userkey, const int bits, AES_KEY *key)
57{
58    key->rounds = rijndaelKeySetupDec(key->key, userkey, bits);
59    if (key->rounds == 0)
60	return -1;
61    return 0;
62}
63
64void
65AES_encrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key)
66{
67    rijndaelEncrypt(key->key, key->rounds, in, out);
68}
69
70void
71AES_decrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key)
72{
73    rijndaelDecrypt(key->key, key->rounds, in, out);
74}
75
76void
77AES_cbc_encrypt(const unsigned char *in, unsigned char *out,
78		unsigned long size, const AES_KEY *key,
79		unsigned char *iv, int forward_encrypt)
80{
81    unsigned char tmp[AES_BLOCK_SIZE];
82    int i;
83
84    if (forward_encrypt) {
85	while (size >= AES_BLOCK_SIZE) {
86	    for (i = 0; i < AES_BLOCK_SIZE; i++)
87		tmp[i] = in[i] ^ iv[i];
88	    AES_encrypt(tmp, out, key);
89	    memcpy(iv, out, AES_BLOCK_SIZE);
90	    size -= AES_BLOCK_SIZE;
91	    in += AES_BLOCK_SIZE;
92	    out += AES_BLOCK_SIZE;
93	}
94	if (size) {
95	    for (i = 0; i < size; i++)
96		tmp[i] = in[i] ^ iv[i];
97	    for (i = size; i < AES_BLOCK_SIZE; i++)
98		tmp[i] = iv[i];
99	    AES_encrypt(tmp, out, key);
100	    memcpy(iv, out, AES_BLOCK_SIZE);
101	}
102    } else {
103	while (size >= AES_BLOCK_SIZE) {
104	    memcpy(tmp, in, AES_BLOCK_SIZE);
105	    AES_decrypt(tmp, out, key);
106	    for (i = 0; i < AES_BLOCK_SIZE; i++)
107		out[i] ^= iv[i];
108	    memcpy(iv, tmp, AES_BLOCK_SIZE);
109	    size -= AES_BLOCK_SIZE;
110	    in += AES_BLOCK_SIZE;
111	    out += AES_BLOCK_SIZE;
112	}
113	if (size) {
114	    memcpy(tmp, in, AES_BLOCK_SIZE);
115	    AES_decrypt(tmp, out, key);
116	    for (i = 0; i < size; i++)
117		out[i] ^= iv[i];
118	    memcpy(iv, tmp, AES_BLOCK_SIZE);
119	}
120    }
121}
122
123void
124AES_cfb8_encrypt(const unsigned char *in, unsigned char *out,
125                 unsigned long size, const AES_KEY *key,
126                 unsigned char *iv, int forward_encrypt)
127{
128    int i;
129
130    for (i = 0; i < size; i++) {
131        unsigned char tmp[AES_BLOCK_SIZE + 1];
132
133        memcpy(tmp, iv, AES_BLOCK_SIZE);
134        AES_encrypt(iv, iv, key);
135        if (!forward_encrypt) {
136            tmp[AES_BLOCK_SIZE] = in[i];
137        }
138        out[i] = in[i] ^ iv[0];
139        if (forward_encrypt) {
140            tmp[AES_BLOCK_SIZE] = out[i];
141        }
142        memcpy(iv, &tmp[1], AES_BLOCK_SIZE);
143    }
144}
145