xref: /openbmc/qemu/crypto/hash-gnutls.c (revision 6fdc5bc1)
1 /*
2  * QEMU Crypto hash algorithms
3  *
4  * Copyright (c) 2021 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 <gnutls/crypto.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] = GNUTLS_DIG_MD5,
30     [QCRYPTO_HASH_ALGO_SHA1] = GNUTLS_DIG_SHA1,
31     [QCRYPTO_HASH_ALGO_SHA224] = GNUTLS_DIG_SHA224,
32     [QCRYPTO_HASH_ALGO_SHA256] = GNUTLS_DIG_SHA256,
33     [QCRYPTO_HASH_ALGO_SHA384] = GNUTLS_DIG_SHA384,
34     [QCRYPTO_HASH_ALGO_SHA512] = GNUTLS_DIG_SHA512,
35     [QCRYPTO_HASH_ALGO_RIPEMD160] = GNUTLS_DIG_RMD160,
36 };
37 
38 gboolean qcrypto_hash_supports(QCryptoHashAlgo alg)
39 {
40     size_t i;
41     const gnutls_digest_algorithm_t *algs;
42     if (alg >= G_N_ELEMENTS(qcrypto_hash_alg_map) ||
43         qcrypto_hash_alg_map[alg] == GNUTLS_DIG_UNKNOWN) {
44         return false;
45     }
46     algs = gnutls_digest_list();
47     for (i = 0; algs[i] != GNUTLS_DIG_UNKNOWN; i++) {
48         if (algs[i] == qcrypto_hash_alg_map[alg]) {
49             return true;
50         }
51     }
52     return false;
53 }
54 
55 
56 static int
57 qcrypto_gnutls_hash_bytesv(QCryptoHashAlgo alg,
58                            const struct iovec *iov,
59                            size_t niov,
60                            uint8_t **result,
61                            size_t *resultlen,
62                            Error **errp)
63 {
64     int i, ret;
65     gnutls_hash_hd_t hash;
66 
67     if (!qcrypto_hash_supports(alg)) {
68         error_setg(errp,
69                    "Unknown hash algorithm %d",
70                    alg);
71         return -1;
72     }
73 
74     ret = gnutls_hash_get_len(qcrypto_hash_alg_map[alg]);
75     if (*resultlen == 0) {
76         *resultlen = ret;
77         *result = g_new0(uint8_t, *resultlen);
78     } else if (*resultlen != ret) {
79         error_setg(errp,
80                    "Result buffer size %zu is smaller than hash %d",
81                    *resultlen, ret);
82         return -1;
83     }
84 
85     ret = gnutls_hash_init(&hash, qcrypto_hash_alg_map[alg]);
86     if (ret < 0) {
87         error_setg(errp,
88                    "Unable to initialize hash algorithm: %s",
89                    gnutls_strerror(ret));
90         return -1;
91     }
92 
93     for (i = 0; i < niov; i++) {
94         gnutls_hash(hash, iov[i].iov_base, iov[i].iov_len);
95     }
96 
97     gnutls_hash_deinit(hash, *result);
98     return 0;
99 }
100 
101 
102 QCryptoHashDriver qcrypto_hash_lib_driver = {
103     .hash_bytesv = qcrypto_gnutls_hash_bytesv,
104 };
105