1 /* $OpenBSD: xform.c,v 1.16 2001/08/28 12:20:43 ben Exp $ */
3 * The authors of this code are John Ioannidis (ji@tla.org),
4 * Angelos D. Keromytis (kermit@csd.uch.gr),
5 * Niels Provos (provos@physnet.uni-hamburg.de) and
6 * Damien Miller (djm@mindrot.org).
8 * This code was written by John Ioannidis for BSD/OS in Athens, Greece,
11 * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
12 * by Angelos D. Keromytis.
14 * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
17 * Additional features in 1999 by Angelos D. Keromytis.
19 * AES XTS implementation in 2008 by Damien Miller
21 * Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
22 * Angelos D. Keromytis and Niels Provos.
24 * Copyright (C) 2001, Angelos D. Keromytis.
26 * Copyright (C) 2008, Damien Miller
27 * Copyright (c) 2014 The FreeBSD Foundation
28 * All rights reserved.
30 * Portions of this software were developed by John-Mark Gurney
31 * under sponsorship of the FreeBSD Foundation and
32 * Rubicon Communications, LLC (Netgate).
34 * Permission to use, copy, and modify this software with or without fee
35 * is hereby granted, provided that this entire notice is included in
36 * all copies of any software which is or includes a copy or
37 * modification of this software.
38 * You may use this code under the GNU public license if you so wish. Please
39 * contribute changes back to the authors under this freer than GPL license
40 * so that we may further the use of strong encryption without limitations to
43 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
44 * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
45 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
46 * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
50 #include <sys/cdefs.h>
51 __FBSDID("$FreeBSD$");
53 #include <sys/types.h>
54 #include <crypto/rijndael/rijndael.h>
55 #include <opencrypto/xform_enc.h>
59 char iv[AES_BLOCK_LEN];
62 static int aes_cbc_setkey(void *, const uint8_t *, int);
63 static void aes_cbc_encrypt(void *, const uint8_t *, uint8_t *);
64 static void aes_cbc_decrypt(void *, const uint8_t *, uint8_t *);
65 static void aes_cbc_encrypt_multi(void *, const uint8_t *, uint8_t *, size_t);
66 static void aes_cbc_decrypt_multi(void *, const uint8_t *, uint8_t *, size_t);
67 static void aes_cbc_reinit(void *, const uint8_t *, size_t);
69 /* Encryption instances */
70 const struct enc_xform enc_xform_aes_cbc = {
71 .type = CRYPTO_AES_CBC,
73 .ctxsize = sizeof(struct aes_cbc_ctx),
74 .blocksize = AES_BLOCK_LEN,
75 .ivsize = AES_BLOCK_LEN,
76 .minkey = AES_MIN_KEY,
77 .maxkey = AES_MAX_KEY,
78 .setkey = aes_cbc_setkey,
79 .reinit = aes_cbc_reinit,
80 .encrypt = aes_cbc_encrypt,
81 .decrypt = aes_cbc_decrypt,
82 .encrypt_multi = aes_cbc_encrypt_multi,
83 .decrypt_multi = aes_cbc_decrypt_multi,
87 * Encryption wrapper routines.
90 aes_cbc_encrypt(void *vctx, const uint8_t *in, uint8_t *out)
92 struct aes_cbc_ctx *ctx = vctx;
94 for (u_int i = 0; i < AES_BLOCK_LEN; i++)
95 out[i] = in[i] ^ ctx->iv[i];
96 rijndael_encrypt(&ctx->key, out, out);
97 memcpy(ctx->iv, out, AES_BLOCK_LEN);
101 aes_cbc_decrypt(void *vctx, const uint8_t *in, uint8_t *out)
103 struct aes_cbc_ctx *ctx = vctx;
104 char block[AES_BLOCK_LEN];
106 memcpy(block, in, AES_BLOCK_LEN);
107 rijndael_decrypt(&ctx->key, in, out);
108 for (u_int i = 0; i < AES_BLOCK_LEN; i++)
109 out[i] ^= ctx->iv[i];
110 memcpy(ctx->iv, block, AES_BLOCK_LEN);
111 explicit_bzero(block, sizeof(block));
115 aes_cbc_encrypt_multi(void *vctx, const uint8_t *in, uint8_t *out, size_t len)
117 struct aes_cbc_ctx *ctx = vctx;
119 KASSERT(len % AES_BLOCK_LEN == 0, ("%s: invalid length", __func__));
121 for (u_int i = 0; i < AES_BLOCK_LEN; i++)
122 out[i] = in[i] ^ ctx->iv[i];
123 rijndael_encrypt(&ctx->key, out, out);
124 memcpy(ctx->iv, out, AES_BLOCK_LEN);
125 out += AES_BLOCK_LEN;
127 len -= AES_BLOCK_LEN;
132 aes_cbc_decrypt_multi(void *vctx, const uint8_t *in, uint8_t *out, size_t len)
134 struct aes_cbc_ctx *ctx = vctx;
135 char block[AES_BLOCK_LEN];
137 KASSERT(len % AES_BLOCK_LEN == 0, ("%s: invalid length", __func__));
139 memcpy(block, in, AES_BLOCK_LEN);
140 rijndael_decrypt(&ctx->key, in, out);
141 for (u_int i = 0; i < AES_BLOCK_LEN; i++)
142 out[i] ^= ctx->iv[i];
143 memcpy(ctx->iv, block, AES_BLOCK_LEN);
144 out += AES_BLOCK_LEN;
146 len -= AES_BLOCK_LEN;
148 explicit_bzero(block, sizeof(block));
152 aes_cbc_setkey(void *vctx, const uint8_t *key, int len)
154 struct aes_cbc_ctx *ctx = vctx;
156 if (len != 16 && len != 24 && len != 32)
159 rijndael_set_key(&ctx->key, key, len * 8);
164 aes_cbc_reinit(void *vctx, const uint8_t *iv, size_t iv_len)
166 struct aes_cbc_ctx *ctx = vctx;
168 KASSERT(iv_len == sizeof(ctx->iv), ("%s: bad IV length", __func__));
169 memcpy(ctx->iv, iv, sizeof(ctx->iv));