qemu/crypto/ivgen.c
Daniel P. Berrange cb730894ae crypto: add support for generating initialization vectors
There are a number of different algorithms that can be used
to generate initialization vectors for disk encryption. This
introduces a simple internal QCryptoBlockIV object to provide
a consistent internal API to the different algorithms. The
initially implemented algorithms are 'plain', 'plain64' and
'essiv', each matching the same named algorithm provided
by the Linux kernel dm-crypt driver.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17 14:41:14 +00:00

100 lines
2.6 KiB
C

/*
* QEMU Crypto block IV generator
*
* 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 "crypto/ivgenpriv.h"
#include "crypto/ivgen-plain.h"
#include "crypto/ivgen-plain64.h"
#include "crypto/ivgen-essiv.h"
QCryptoIVGen *qcrypto_ivgen_new(QCryptoIVGenAlgorithm alg,
QCryptoCipherAlgorithm cipheralg,
QCryptoHashAlgorithm hash,
const uint8_t *key, size_t nkey,
Error **errp)
{
QCryptoIVGen *ivgen = g_new0(QCryptoIVGen, 1);
ivgen->algorithm = alg;
ivgen->cipher = cipheralg;
ivgen->hash = hash;
switch (alg) {
case QCRYPTO_IVGEN_ALG_PLAIN:
ivgen->driver = &qcrypto_ivgen_plain;
break;
case QCRYPTO_IVGEN_ALG_PLAIN64:
ivgen->driver = &qcrypto_ivgen_plain64;
break;
case QCRYPTO_IVGEN_ALG_ESSIV:
ivgen->driver = &qcrypto_ivgen_essiv;
break;
default:
error_setg(errp, "Unknown block IV generator algorithm %d", alg);
g_free(ivgen);
return NULL;
}
if (ivgen->driver->init(ivgen, key, nkey, errp) < 0) {
g_free(ivgen);
return NULL;
}
return ivgen;
}
int qcrypto_ivgen_calculate(QCryptoIVGen *ivgen,
uint64_t sector,
uint8_t *iv, size_t niv,
Error **errp)
{
return ivgen->driver->calculate(ivgen, sector, iv, niv, errp);
}
QCryptoIVGenAlgorithm qcrypto_ivgen_get_algorithm(QCryptoIVGen *ivgen)
{
return ivgen->algorithm;
}
QCryptoCipherAlgorithm qcrypto_ivgen_get_cipher(QCryptoIVGen *ivgen)
{
return ivgen->cipher;
}
QCryptoHashAlgorithm qcrypto_ivgen_get_hash(QCryptoIVGen *ivgen)
{
return ivgen->hash;
}
void qcrypto_ivgen_free(QCryptoIVGen *ivgen)
{
if (!ivgen) {
return;
}
ivgen->driver->cleanup(ivgen);
g_free(ivgen);
}