oysteikt/heimdal
0
0
Fork 0
Code Issues 5 Pull Requests Releases Activity

add aes cts

Browse Source 
git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@23553 ec53bebd-3082-4978-b11e-865c3cabbd6b
This commit is contained in:
Love Hörnquist Åstrand
2008-08-16 23:01:35 +00:00
parent dcf1a2fea0
commit 7d2c2bfd04
1 changed files with 264 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

264
lib/hcrypto/evp-aes-cts.c Normal file
View File

@@ -0,0 +1,264 @@
/*
* Copyright (c) 2006 - 2007 Kungliga Tekniska H<>gskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
RCSID("$Id$");
#define HC_DEPRECATED
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <evp.h>
#include <krb5-types.h>
#include <aes.h>
/*
*
*/
static int
aes_cts_init(EVP_CIPHER_CTX *ctx,
const unsigned char * key,
const unsigned char * iv,
int encp)
{
AES_KEY *k = ctx->cipher_data;
if (ctx->encrypt)
AES_set_encrypt_key(key, ctx->cipher->key_len * 8, k);
else
AES_set_decrypt_key(key, ctx->cipher->key_len * 8, k);
return 1;
}
static void
_krb5_aes_cts_encrypt(const unsigned char *in, unsigned char *out,
size_t len, const AES_KEY *key,
unsigned char *ivec, const int encryptp)
{
unsigned char tmp[AES_BLOCK_SIZE];
int i;
/*
* In the framework of kerberos, the length can never be shorter
* then at least one blocksize.
*/
if (encryptp) {
while(len > AES_BLOCK_SIZE) {
for (i = 0; i < AES_BLOCK_SIZE; i++)
tmp[i] = in[i] ^ ivec[i];
AES_encrypt(tmp, out, key);
memcpy(ivec, out, AES_BLOCK_SIZE);
len -= AES_BLOCK_SIZE;
in += AES_BLOCK_SIZE;
out += AES_BLOCK_SIZE;
}
for (i = 0; i < len; i++)
tmp[i] = in[i] ^ ivec[i];
for (; i < AES_BLOCK_SIZE; i++)
tmp[i] = 0 ^ ivec[i];
AES_encrypt(tmp, out - AES_BLOCK_SIZE, key);
memcpy(out, ivec, len);
memcpy(ivec, out - AES_BLOCK_SIZE, AES_BLOCK_SIZE);
} else {
unsigned char tmp2[AES_BLOCK_SIZE];
unsigned char tmp3[AES_BLOCK_SIZE];
while(len > AES_BLOCK_SIZE * 2) {
memcpy(tmp, in, AES_BLOCK_SIZE);
AES_decrypt(in, out, key);
for (i = 0; i < AES_BLOCK_SIZE; i++)
out[i] ^= ivec[i];
memcpy(ivec, tmp, AES_BLOCK_SIZE);
len -= AES_BLOCK_SIZE;
in += AES_BLOCK_SIZE;
out += AES_BLOCK_SIZE;
}
len -= AES_BLOCK_SIZE;
memcpy(tmp, in, AES_BLOCK_SIZE); /* save last iv */
AES_decrypt(in, tmp2, key);
memcpy(tmp3, in + AES_BLOCK_SIZE, len);
memcpy(tmp3 + len, tmp2 + len, AES_BLOCK_SIZE - len); /* xor 0 */
for (i = 0; i < len; i++)
out[i + AES_BLOCK_SIZE] = tmp2[i] ^ tmp3[i];
AES_decrypt(tmp3, out, key);
for (i = 0; i < AES_BLOCK_SIZE; i++)
out[i] ^= ivec[i];
memcpy(ivec, tmp, AES_BLOCK_SIZE);
}
}
static int
aes_cts_do_cipher(EVP_CIPHER_CTX *ctx,
unsigned char *out,
const unsigned char *in,
unsigned int len)
{
AES_KEY *k = ctx->cipher_data;
unsigned char local_ivec[AES_BLOCK_SIZE], *ivec;
if (len < AES_BLOCK_SIZE)
abort(); /* krb5_abortx(context, "invalid use of AES_CTS_encrypt"); */
if (len == AES_BLOCK_SIZE) {
if (ctx->encrypt)
AES_encrypt(in, out, k);
else
AES_decrypt(in, out, k);
} else {
ivec = ctx->iv;
if(ivec == NULL) {
memset(local_ivec, 0, sizeof(local_ivec));
ivec = local_ivec;
}
_krb5_aes_cts_encrypt(in, out, len, k, ivec, ctx->encrypt);
}
return 1;
}
static int
aes_cts_cleanup(EVP_CIPHER_CTX *ctx)
{
memset(ctx->cipher_data, 0, sizeof(AES_KEY));
return 1;
}
/**
* The AES-128 cts cipher type (hcrypto)
*
* @return the AES-128 EVP_CIPHER pointer.
*
* @ingroup hcrypto_evp
*/
const EVP_CIPHER *
EVP_hcrypto_aes_128_cts(void)
{
static const EVP_CIPHER aes_128_cts = {
0,
1,
16,
16,
EVP_CIPH_CBC_MODE,
aes_cts_init,
aes_cts_do_cipher,
aes_cts_cleanup,
sizeof(AES_KEY),
NULL,
NULL,
NULL,
NULL
};
return &aes_128_cts;
}
/**
* The AES-192 cts cipher type (hcrypto)
*
* @return the AES-192 EVP_CIPHER pointer.
*
* @ingroup hcrypto_evp
*/
const EVP_CIPHER *
EVP_hcrypto_aes_192_cts(void)
{
static const EVP_CIPHER aes_192_cts = {
0,
1,
24,
16,
EVP_CIPH_CBC_MODE,
aes_cts_init,
aes_cts_do_cipher,
aes_cts_cleanup,
sizeof(AES_KEY),
NULL,
NULL,
NULL,
NULL
};
return &aes_192_cts;
}
/**
* The AES-256 cts cipher type (hcrypto)
*
* @return the AES-256 EVP_CIPHER pointer.
*
* @ingroup hcrypto_evp
*/
const EVP_CIPHER *
EVP_hcrypto_aes_256_cts(void)
{
static const EVP_CIPHER aes_256_cts = {
0,
1,
32,
16,
EVP_CIPH_CBC_MODE,
aes_cts_init,
aes_cts_do_cipher,
aes_cts_cleanup,
sizeof(AES_KEY),
NULL,
NULL,
NULL,
NULL
};
return &aes_256_cts;
}