/* $OpenBSD: xform.c,v 1.16 2001/08/28 12:20:43 ben Exp $ */
/*-
* The authors of this code are John Ioannidis (ji@tla.org),
* Angelos D. Keromytis (kermit@csd.uch.gr),
* Niels Provos (provos@physnet.uni-hamburg.de) and
* Damien Miller (djm@mindrot.org).
*
* This code was written by John Ioannidis for BSD/OS in Athens, Greece,
* in November 1995.
*
* Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
* by Angelos D. Keromytis.
*
* Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
* and Niels Provos.
*
* Additional features in 1999 by Angelos D. Keromytis.
*
* AES XTS implementation in 2008 by Damien Miller
*
* Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
* Angelos D. Keromytis and Niels Provos.
*
* Copyright (C) 2001, Angelos D. Keromytis.
*
* Copyright (C) 2008, Damien Miller
* Copyright (c) 2014 The FreeBSD Foundation
* All rights reserved.
*
* Portions of this software were developed by John-Mark Gurney
* under sponsorship of the FreeBSD Foundation and
* Rubicon Communications, LLC (Netgate).
*
* Permission to use, copy, and modify this software with or without fee
* is hereby granted, provided that this entire notice is included in
* all copies of any software which is or includes a copy or
* modification of this software.
* You may use this code under the GNU public license if you so wish. Please
* contribute changes back to the authors under this freer than GPL license
* so that we may further the use of strong encryption without limitations to
* all.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
* PURPOSE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <opencrypto/xform_enc.h>
static int aes_icm_setkey(u_int8_t **, u_int8_t *, int);
static void aes_icm_crypt(caddr_t, u_int8_t *);
static void aes_icm_zerokey(u_int8_t **);
static void aes_icm_reinit(caddr_t, u_int8_t *);
static void aes_gcm_reinit(caddr_t, u_int8_t *);
/* Encryption instances */
struct enc_xform enc_xform_aes_icm = {
CRYPTO_AES_ICM, "AES-ICM",
AES_BLOCK_LEN, AES_BLOCK_LEN, AES_MIN_KEY, AES_MAX_KEY,
aes_icm_crypt,
aes_icm_crypt,
aes_icm_setkey,
aes_icm_zerokey,
aes_icm_reinit,
};
struct enc_xform enc_xform_aes_nist_gcm = {
CRYPTO_AES_NIST_GCM_16, "AES-GCM",
AES_ICM_BLOCK_LEN, AES_GCM_IV_LEN, AES_MIN_KEY, AES_MAX_KEY,
aes_icm_crypt,
aes_icm_crypt,
aes_icm_setkey,
aes_icm_zerokey,
aes_gcm_reinit,
};
/*
* Encryption wrapper routines.
*/
static void
aes_icm_reinit(caddr_t key, u_int8_t *iv)
{
struct aes_icm_ctx *ctx;
ctx = (struct aes_icm_ctx *)key;
bcopy(iv, ctx->ac_block, AESICM_BLOCKSIZE);
}
static void
aes_gcm_reinit(caddr_t key, u_int8_t *iv)
{
struct aes_icm_ctx *ctx;
aes_icm_reinit(key, iv);
ctx = (struct aes_icm_ctx *)key;
/* GCM starts with 2 as counter 1 is used for final xor of tag. */
bzero(&ctx->ac_block[AESICM_BLOCKSIZE - 4], 4);
ctx->ac_block[AESICM_BLOCKSIZE - 1] = 2;
}
static void
aes_icm_crypt(caddr_t key, u_int8_t *data)
{
struct aes_icm_ctx *ctx;
u_int8_t keystream[AESICM_BLOCKSIZE];
int i;
ctx = (struct aes_icm_ctx *)key;
rijndaelEncrypt(ctx->ac_ek, ctx->ac_nr, ctx->ac_block, keystream);
for (i = 0; i < AESICM_BLOCKSIZE; i++)
data[i] ^= keystream[i];
explicit_bzero(keystream, sizeof(keystream));
/* increment counter */
for (i = AESICM_BLOCKSIZE - 1;
i >= 0; i--)
if (++ctx->ac_block[i]) /* continue on overflow */
break;
}
static int
aes_icm_setkey(u_int8_t **sched, u_int8_t *key, int len)
{
struct aes_icm_ctx *ctx;
if (len != 16 && len != 24 && len != 32)
return EINVAL;
*sched = KMALLOC(sizeof(struct aes_icm_ctx), M_CRYPTO_DATA,
M_NOWAIT | M_ZERO);
if (*sched == NULL)
return ENOMEM;
ctx = (struct aes_icm_ctx *)*sched;
ctx->ac_nr = rijndaelKeySetupEnc(ctx->ac_ek, (u_char *)key, len * 8);
return 0;
}
static void
aes_icm_zerokey(u_int8_t **sched)
{
bzero(*sched, sizeof(struct aes_icm_ctx));
KFREE(*sched, M_CRYPTO_DATA);
*sched = NULL;
}
