mirror of https://gitee.com/openkylin/qemu.git
122 lines
3.5 KiB
C
122 lines
3.5 KiB
C
/*
|
|
* QEMU Crypto block IV generator - essiv
|
|
*
|
|
* Copyright (c) 2015-2016 Red Hat, Inc.
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
#include "qapi/error.h"
|
|
#include "qemu/bswap.h"
|
|
#include "crypto/ivgen-essiv.h"
|
|
|
|
typedef struct QCryptoIVGenESSIV QCryptoIVGenESSIV;
|
|
struct QCryptoIVGenESSIV {
|
|
QCryptoCipher *cipher;
|
|
};
|
|
|
|
static int qcrypto_ivgen_essiv_init(QCryptoIVGen *ivgen,
|
|
const uint8_t *key, size_t nkey,
|
|
Error **errp)
|
|
{
|
|
uint8_t *salt;
|
|
size_t nhash;
|
|
size_t nsalt;
|
|
QCryptoIVGenESSIV *essiv = g_new0(QCryptoIVGenESSIV, 1);
|
|
|
|
/* Not necessarily the same as nkey */
|
|
nsalt = qcrypto_cipher_get_key_len(ivgen->cipher);
|
|
|
|
nhash = qcrypto_hash_digest_len(ivgen->hash);
|
|
/* Salt must be larger of hash size or key size */
|
|
salt = g_new0(uint8_t, MAX(nhash, nsalt));
|
|
|
|
if (qcrypto_hash_bytes(ivgen->hash, (const gchar *)key, nkey,
|
|
&salt, &nhash,
|
|
errp) < 0) {
|
|
g_free(essiv);
|
|
g_free(salt);
|
|
return -1;
|
|
}
|
|
|
|
/* Now potentially truncate salt to match cipher key len */
|
|
essiv->cipher = qcrypto_cipher_new(ivgen->cipher,
|
|
QCRYPTO_CIPHER_MODE_ECB,
|
|
salt, MIN(nhash, nsalt),
|
|
errp);
|
|
if (!essiv->cipher) {
|
|
g_free(essiv);
|
|
g_free(salt);
|
|
return -1;
|
|
}
|
|
|
|
g_free(salt);
|
|
ivgen->private = essiv;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int qcrypto_ivgen_essiv_calculate(QCryptoIVGen *ivgen,
|
|
uint64_t sector,
|
|
uint8_t *iv, size_t niv,
|
|
Error **errp)
|
|
{
|
|
QCryptoIVGenESSIV *essiv = ivgen->private;
|
|
size_t ndata = qcrypto_cipher_get_block_len(ivgen->cipher);
|
|
uint8_t *data = g_new(uint8_t, ndata);
|
|
|
|
sector = cpu_to_le64(sector);
|
|
memcpy(data, (uint8_t *)§or, ndata);
|
|
if (sizeof(sector) < ndata) {
|
|
memset(data + sizeof(sector), 0, ndata - sizeof(sector));
|
|
}
|
|
|
|
if (qcrypto_cipher_encrypt(essiv->cipher,
|
|
data,
|
|
data,
|
|
ndata,
|
|
errp) < 0) {
|
|
g_free(data);
|
|
return -1;
|
|
}
|
|
|
|
if (ndata > niv) {
|
|
ndata = niv;
|
|
}
|
|
memcpy(iv, data, ndata);
|
|
if (ndata < niv) {
|
|
memset(iv + ndata, 0, niv - ndata);
|
|
}
|
|
g_free(data);
|
|
return 0;
|
|
}
|
|
|
|
static void qcrypto_ivgen_essiv_cleanup(QCryptoIVGen *ivgen)
|
|
{
|
|
QCryptoIVGenESSIV *essiv = ivgen->private;
|
|
|
|
qcrypto_cipher_free(essiv->cipher);
|
|
g_free(essiv);
|
|
}
|
|
|
|
|
|
struct QCryptoIVGenDriver qcrypto_ivgen_essiv = {
|
|
.init = qcrypto_ivgen_essiv_init,
|
|
.calculate = qcrypto_ivgen_essiv_calculate,
|
|
.cleanup = qcrypto_ivgen_essiv_cleanup,
|
|
};
|
|
|