xref: /openbmc/qemu/crypto/hash-gcrypt.c (revision d0f0cd5b)
1 /*
2  * QEMU Crypto hash algorithms
3  *
4  * Copyright (c) 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 <gcrypt.h>
23 #include "qapi/error.h"
24 #include "crypto/hash.h"
25 #include "hashpriv.h"
26 
27 
28 static int qcrypto_hash_alg_map[QCRYPTO_HASH_ALGO__MAX] = {
29     [QCRYPTO_HASH_ALGO_MD5] = GCRY_MD_MD5,
30     [QCRYPTO_HASH_ALGO_SHA1] = GCRY_MD_SHA1,
31     [QCRYPTO_HASH_ALGO_SHA224] = GCRY_MD_SHA224,
32     [QCRYPTO_HASH_ALGO_SHA256] = GCRY_MD_SHA256,
33     [QCRYPTO_HASH_ALGO_SHA384] = GCRY_MD_SHA384,
34     [QCRYPTO_HASH_ALGO_SHA512] = GCRY_MD_SHA512,
35     [QCRYPTO_HASH_ALGO_RIPEMD160] = GCRY_MD_RMD160,
36 };
37 
38 gboolean qcrypto_hash_supports(QCryptoHashAlgo alg)
39 {
40     if (alg < G_N_ELEMENTS(qcrypto_hash_alg_map) &&
41         qcrypto_hash_alg_map[alg] != GCRY_MD_NONE) {
42         return true;
43     }
44     return false;
45 }
46 
47 
48 static int
49 qcrypto_gcrypt_hash_bytesv(QCryptoHashAlgo alg,
50                            const struct iovec *iov,
51                            size_t niov,
52                            uint8_t **result,
53                            size_t *resultlen,
54                            Error **errp)
55 {
56     int i, ret;
57     gcry_md_hd_t md;
58     unsigned char *digest;
59 
60     if (!qcrypto_hash_supports(alg)) {
61         error_setg(errp,
62                    "Unknown hash algorithm %d",
63                    alg);
64         return -1;
65     }
66 
67     ret = gcry_md_open(&md, qcrypto_hash_alg_map[alg], 0);
68 
69     if (ret < 0) {
70         error_setg(errp,
71                    "Unable to initialize hash algorithm: %s",
72                    gcry_strerror(ret));
73         return -1;
74     }
75 
76     for (i = 0; i < niov; i++) {
77         gcry_md_write(md, iov[i].iov_base, iov[i].iov_len);
78     }
79 
80     ret = gcry_md_get_algo_dlen(qcrypto_hash_alg_map[alg]);
81     if (ret <= 0) {
82         error_setg(errp,
83                    "Unable to get hash length: %s",
84                    gcry_strerror(ret));
85         goto error;
86     }
87     if (*resultlen == 0) {
88         *resultlen = ret;
89         *result = g_new0(uint8_t, *resultlen);
90     } else if (*resultlen != ret) {
91         error_setg(errp,
92                    "Result buffer size %zu is smaller than hash %d",
93                    *resultlen, ret);
94         goto error;
95     }
96 
97     digest = gcry_md_read(md, 0);
98     if (!digest) {
99         error_setg(errp,
100                    "No digest produced");
101         goto error;
102     }
103     memcpy(*result, digest, *resultlen);
104 
105     gcry_md_close(md);
106     return 0;
107 
108  error:
109     gcry_md_close(md);
110     return -1;
111 }
112 
113 
114 QCryptoHashDriver qcrypto_hash_lib_driver = {
115     .hash_bytesv = qcrypto_gcrypt_hash_bytesv,
116 };
117