1 /* $NetBSD: aes.c,v 1.2 2017/01/28 21:31:47 christos Exp $ */
2
3 /*
4 * Copyright (c) 2003 Kungliga Tekniska Högskolan
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 #include <krb5/roken.h>
38
39 #ifdef KRB5
40 #include <krb5/krb5-types.h>
41 #endif
42
43 #include "rijndael-alg-fst.h"
44 #include "aes.h"
45
46 int
AES_set_encrypt_key(const unsigned char * userkey,const int bits,AES_KEY * key)47 AES_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
55 int
AES_set_decrypt_key(const unsigned char * userkey,const int bits,AES_KEY * key)56 AES_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
64 void
AES_encrypt(const unsigned char * in,unsigned char * out,const AES_KEY * key)65 AES_encrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key)
66 {
67 rijndaelEncrypt(key->key, key->rounds, in, out);
68 }
69
70 void
AES_decrypt(const unsigned char * in,unsigned char * out,const AES_KEY * key)71 AES_decrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key)
72 {
73 rijndaelDecrypt(key->key, key->rounds, in, out);
74 }
75
76 void
AES_cbc_encrypt(const unsigned char * in,unsigned char * out,unsigned long size,const AES_KEY * key,unsigned char * iv,int forward_encrypt)77 AES_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
123 void
AES_cfb8_encrypt(const unsigned char * in,unsigned char * out,unsigned long size,const AES_KEY * key,unsigned char * iv,int forward_encrypt)124 AES_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