xref: /qemu/crypto/ivgen-plain64.c (revision abff1abf)
1 /*
2  * QEMU Crypto block IV generator - plain
3  *
4  * Copyright (c) 2015-2016 Red Hat, Inc.
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  *
19  */
20 
21 #include "qemu/osdep.h"
22 #include "qemu/bswap.h"
23 #include "ivgen-plain.h"
24 
25 static int qcrypto_ivgen_plain_init(QCryptoIVGen *ivgen,
26                                     const uint8_t *key, size_t nkey,
27                                     Error **errp)
28 {
29     return 0;
30 }
31 
32 static int qcrypto_ivgen_plain_calculate(QCryptoIVGen *ivgen,
33                                          uint64_t sector,
34                                          uint8_t *iv, size_t niv,
35                                          Error **errp)
36 {
37     size_t ivprefix;
38     ivprefix = sizeof(sector);
39     sector = cpu_to_le64(sector);
40     if (ivprefix > niv) {
41         ivprefix = niv;
42     }
43     memcpy(iv, &sector, ivprefix);
44     if (ivprefix < niv) {
45         memset(iv + ivprefix, 0, niv - ivprefix);
46     }
47     return 0;
48 }
49 
50 static void qcrypto_ivgen_plain_cleanup(QCryptoIVGen *ivgen)
51 {
52 }
53 
54 
55 struct QCryptoIVGenDriver qcrypto_ivgen_plain64 = {
56     .init = qcrypto_ivgen_plain_init,
57     .calculate = qcrypto_ivgen_plain_calculate,
58     .cleanup = qcrypto_ivgen_plain_cleanup,
59 };
60 
61