xref: /openbmc/qemu/crypto/hash-gcrypt.c (revision 700784bf)
1 /*
2  * QEMU Crypto hash algorithms
3  *
4  * Copyright (c) 2024 Seagate Technology LLC and/or its Affiliates
5  * Copyright (c) 2016 Red Hat, Inc.
6  *
7  * This library is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * This library is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19  *
20  */
21 
22 #include "qemu/osdep.h"
23 #include <gcrypt.h>
24 #include "qapi/error.h"
25 #include "crypto/hash.h"
26 #include "hashpriv.h"
27 
28 
29 static int qcrypto_hash_alg_map[QCRYPTO_HASH_ALGO__MAX] = {
30     [QCRYPTO_HASH_ALGO_MD5] = GCRY_MD_MD5,
31     [QCRYPTO_HASH_ALGO_SHA1] = GCRY_MD_SHA1,
32     [QCRYPTO_HASH_ALGO_SHA224] = GCRY_MD_SHA224,
33     [QCRYPTO_HASH_ALGO_SHA256] = GCRY_MD_SHA256,
34     [QCRYPTO_HASH_ALGO_SHA384] = GCRY_MD_SHA384,
35     [QCRYPTO_HASH_ALGO_SHA512] = GCRY_MD_SHA512,
36     [QCRYPTO_HASH_ALGO_RIPEMD160] = GCRY_MD_RMD160,
37 #ifdef CONFIG_CRYPTO_SM3
38     [QCRYPTO_HASH_ALGO_SM3] = GCRY_MD_SM3,
39 #endif
40 };
41 
42 gboolean qcrypto_hash_supports(QCryptoHashAlgo alg)
43 {
44     if (alg < G_N_ELEMENTS(qcrypto_hash_alg_map) &&
45         qcrypto_hash_alg_map[alg] != GCRY_MD_NONE) {
46         return gcry_md_test_algo(qcrypto_hash_alg_map[alg]) == 0;
47     }
48     return false;
49 }
50 
51 static
52 QCryptoHash *qcrypto_gcrypt_hash_new(QCryptoHashAlgo alg, Error **errp)
53 {
54     QCryptoHash *hash;
55     gcry_error_t ret;
56 
57     hash = g_new(QCryptoHash, 1);
58     hash->alg = alg;
59     hash->opaque = g_new(gcry_md_hd_t, 1);
60 
61     ret = gcry_md_open((gcry_md_hd_t *) hash->opaque,
62                        qcrypto_hash_alg_map[alg], 0);
63     if (ret != 0) {
64         error_setg(errp,
65                    "Unable to initialize hash algorithm: %s",
66                    gcry_strerror(ret));
67         g_free(hash->opaque);
68         g_free(hash);
69         return NULL;
70     }
71     return hash;
72 }
73 
74 static
75 void qcrypto_gcrypt_hash_free(QCryptoHash *hash)
76 {
77     gcry_md_hd_t *ctx = hash->opaque;
78 
79     if (ctx) {
80         gcry_md_close(*ctx);
81         g_free(ctx);
82     }
83 
84     g_free(hash);
85 }
86 
87 
88 static
89 int qcrypto_gcrypt_hash_update(QCryptoHash *hash,
90                                const struct iovec *iov,
91                                size_t niov,
92                                Error **errp)
93 {
94     gcry_md_hd_t *ctx = hash->opaque;
95 
96     for (int i = 0; i < niov; i++) {
97         gcry_md_write(*ctx, iov[i].iov_base, iov[i].iov_len);
98     }
99 
100     return 0;
101 }
102 
103 static
104 int qcrypto_gcrypt_hash_finalize(QCryptoHash *hash,
105                                  uint8_t **result,
106                                  size_t *result_len,
107                                  Error **errp)
108 {
109     int ret;
110     unsigned char *digest;
111     gcry_md_hd_t *ctx = hash->opaque;
112 
113     ret = gcry_md_get_algo_dlen(qcrypto_hash_alg_map[hash->alg]);
114     if (ret == 0) {
115         error_setg(errp, "Unable to get hash length");
116         return -1;
117     }
118 
119     if (*result_len == 0) {
120         *result_len = ret;
121         *result = g_new(uint8_t, *result_len);
122     } else if (*result_len != ret) {
123         error_setg(errp,
124                    "Result buffer size %zu is smaller than hash %d",
125                    *result_len, ret);
126         return -1;
127     }
128 
129     /* Digest is freed by gcry_md_close(), copy it */
130     digest = gcry_md_read(*ctx, 0);
131     memcpy(*result, digest, *result_len);
132     return 0;
133 }
134 
135 QCryptoHashDriver qcrypto_hash_lib_driver = {
136     .hash_new      = qcrypto_gcrypt_hash_new,
137     .hash_update   = qcrypto_gcrypt_hash_update,
138     .hash_finalize = qcrypto_gcrypt_hash_finalize,
139     .hash_free     = qcrypto_gcrypt_hash_free,
140 };
141