aes.c revision 1.1 
1/*	$NetBSD: aes.c,v 1.1 2011/04/13 18:14:49 elric Exp $	*/
2
3/*
4 * Copyright (c) 2003 Kungliga Tekniska H��gskolan
5 * (Royal Institute of Technology, Stockholm, Sweden).
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * 3. Neither the name of the Institute nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#include "config.h"
37
38
39#ifdef KRB5
40#include <krb5/krb5-types.h>
41#endif
42
43#include <string.h>
44
45#include "rijndael-alg-fst.h"
46#include "aes.h"
47
48int
49AES_set_encrypt_key(const unsigned char *userkey, const int bits, AES_KEY *key)
50{
51    key->rounds = rijndaelKeySetupEnc(key->key, userkey, bits);
52    if (key->rounds == 0)
53	return -1;
54    return 0;
55}
56
57int
58AES_set_decrypt_key(const unsigned char *userkey, const int bits, AES_KEY *key)
59{
60    key->rounds = rijndaelKeySetupDec(key->key, userkey, bits);
61    if (key->rounds == 0)
62	return -1;
63    return 0;
64}
65
66void
67AES_encrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key)
68{
69    rijndaelEncrypt(key->key, key->rounds, in, out);
70}
71
72void
73AES_decrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key)
74{
75    rijndaelDecrypt(key->key, key->rounds, in, out);
76}
77
78void
79AES_cbc_encrypt(const unsigned char *in, unsigned char *out,
80		unsigned long size, const AES_KEY *key,
81		unsigned char *iv, int forward_encrypt)
82{
83    unsigned char tmp[AES_BLOCK_SIZE];
84    int i;
85
86    if (forward_encrypt) {
87	while (size >= AES_BLOCK_SIZE) {
88	    for (i = 0; i < AES_BLOCK_SIZE; i++)
89		tmp[i] = in[i] ^ iv[i];
90	    AES_encrypt(tmp, out, key);
91	    memcpy(iv, out, AES_BLOCK_SIZE);
92	    size -= AES_BLOCK_SIZE;
93	    in += AES_BLOCK_SIZE;
94	    out += AES_BLOCK_SIZE;
95	}
96	if (size) {
97	    for (i = 0; i < size; i++)
98		tmp[i] = in[i] ^ iv[i];
99	    for (i = size; i < AES_BLOCK_SIZE; i++)
100		tmp[i] = iv[i];
101	    AES_encrypt(tmp, out, key);
102	    memcpy(iv, out, AES_BLOCK_SIZE);
103	}
104    } else {
105	while (size >= AES_BLOCK_SIZE) {
106	    memcpy(tmp, in, AES_BLOCK_SIZE);
107	    AES_decrypt(tmp, out, key);
108	    for (i = 0; i < AES_BLOCK_SIZE; i++)
109		out[i] ^= iv[i];
110	    memcpy(iv, tmp, AES_BLOCK_SIZE);
111	    size -= AES_BLOCK_SIZE;
112	    in += AES_BLOCK_SIZE;
113	    out += AES_BLOCK_SIZE;
114	}
115	if (size) {
116	    memcpy(tmp, in, AES_BLOCK_SIZE);
117	    AES_decrypt(tmp, out, key);
118	    for (i = 0; i < size; i++)
119		out[i] ^= iv[i];
120	    memcpy(iv, tmp, AES_BLOCK_SIZE);
121	}
122    }
123}
124
125void
126AES_cfb8_encrypt(const unsigned char *in, unsigned char *out,
127                 unsigned long size, const AES_KEY *key,
128                 unsigned char *iv, int forward_encrypt)
129{
130    int i;
131
132    for (i = 0; i < size; i++) {
133        unsigned char tmp[AES_BLOCK_SIZE + 1];
134
135        memcpy(tmp, iv, AES_BLOCK_SIZE);
136        AES_encrypt(iv, iv, key);
137        if (!forward_encrypt) {
138            tmp[AES_BLOCK_SIZE] = in[i];
139        }
140        out[i] = in[i] ^ iv[0];
141        if (forward_encrypt) {
142            tmp[AES_BLOCK_SIZE] = out[i];
143        }
144        memcpy(iv, &tmp[1], AES_BLOCK_SIZE);
145    }
146}
147