xref: /openbmc/qemu/crypto/cipher.c (revision 14b61600)
1 /*
2  * QEMU Crypto cipher algorithms
3  *
4  * Copyright (c) 2015 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 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 "crypto/cipher.h"
22 
23 
24 static size_t alg_key_len[QCRYPTO_CIPHER_ALG_LAST] = {
25     [QCRYPTO_CIPHER_ALG_AES_128] = 16,
26     [QCRYPTO_CIPHER_ALG_AES_192] = 24,
27     [QCRYPTO_CIPHER_ALG_AES_256] = 32,
28     [QCRYPTO_CIPHER_ALG_DES_RFB] = 8,
29 };
30 
31 static bool
32 qcrypto_cipher_validate_key_length(QCryptoCipherAlgorithm alg,
33                                    size_t nkey,
34                                    Error **errp)
35 {
36     if ((unsigned)alg >= QCRYPTO_CIPHER_ALG_LAST) {
37         error_setg(errp, "Cipher algorithm %d out of range",
38                    alg);
39         return false;
40     }
41 
42     if (alg_key_len[alg] != nkey) {
43         error_setg(errp, "Cipher key length %zu should be %zu",
44                    alg_key_len[alg], nkey);
45         return false;
46     }
47     return true;
48 }
49 
50 #if defined(CONFIG_GCRYPT) || defined(CONFIG_NETTLE)
51 static uint8_t *
52 qcrypto_cipher_munge_des_rfb_key(const uint8_t *key,
53                                  size_t nkey)
54 {
55     uint8_t *ret = g_new0(uint8_t, nkey);
56     size_t i;
57     for (i = 0; i < nkey; i++) {
58         uint8_t r = key[i];
59         r = (r & 0xf0) >> 4 | (r & 0x0f) << 4;
60         r = (r & 0xcc) >> 2 | (r & 0x33) << 2;
61         r = (r & 0xaa) >> 1 | (r & 0x55) << 1;
62         ret[i] = r;
63     }
64     return ret;
65 }
66 #endif /* CONFIG_GCRYPT || CONFIG_NETTLE */
67 
68 #ifdef CONFIG_GCRYPT
69 #include "crypto/cipher-gcrypt.c"
70 #elif defined CONFIG_NETTLE
71 #include "crypto/cipher-nettle.c"
72 #else
73 #include "crypto/cipher-builtin.c"
74 #endif
75