qemu/crypto/pbkdf-nettle.c
Daniel P. Berrange 37788f253a crypto: add support for PBKDF2 algorithm
The LUKS data format includes use of PBKDF2 (Password-Based
Key Derivation Function). The Nettle library can provide
an implementation of this, but we don't want code directly
depending on a specific crypto library backend. Introduce
a new include/crypto/pbkdf.h header which defines a QEMU
API for invoking PBKDK2. The initial implementations are
backed by nettle & gcrypt, which are commonly available
with distros shipping GNUTLS.

The test suite data is taken from the cryptsetup codebase
under the LGPLv2.1+ license. This merely aims to verify
that whatever backend we provide for this function in QEMU
will comply with the spec.

Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17 14:41:07 +00:00

66 lines
1.9 KiB
C

/*
* QEMU Crypto PBKDF support (Password-Based Key Derivation Function)
*
* 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/pbkdf.h"
#include "nettle/pbkdf2.h"
bool qcrypto_pbkdf2_supports(QCryptoHashAlgorithm hash)
{
switch (hash) {
case QCRYPTO_HASH_ALG_SHA1:
case QCRYPTO_HASH_ALG_SHA256:
return true;
default:
return false;
}
}
int qcrypto_pbkdf2(QCryptoHashAlgorithm hash,
const uint8_t *key, size_t nkey,
const uint8_t *salt, size_t nsalt,
unsigned int iterations,
uint8_t *out, size_t nout,
Error **errp)
{
switch (hash) {
case QCRYPTO_HASH_ALG_SHA1:
pbkdf2_hmac_sha1(nkey, key,
iterations,
nsalt, salt,
nout, out);
break;
case QCRYPTO_HASH_ALG_SHA256:
pbkdf2_hmac_sha256(nkey, key,
iterations,
nsalt, salt,
nout, out);
break;
default:
error_setg_errno(errp, ENOSYS,
"PBKDF does not support hash algorithm %d", hash);
return -1;
}
return 0;
}