xref: /openbmc/qemu/crypto/init.c (revision b45c03f5)
1 /*
2  * QEMU Crypto initialization
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/init.h"
22 #include "qemu/thread.h"
23 
24 #ifdef CONFIG_GNUTLS
25 #include <gnutls/gnutls.h>
26 #include <gnutls/crypto.h>
27 
28 #ifdef CONFIG_GNUTLS_GCRYPT
29 #include <gcrypt.h>
30 #endif
31 
32 /* #define DEBUG_GNUTLS */
33 
34 /*
35  * If GNUTLS is built against GCrypt then
36  *
37  *  - When GNUTLS >= 2.12, we must not initialize gcrypt threading
38  *    because GNUTLS will do that itself
39  *  - When GNUTLS < 2.12 we must always initialize gcrypt threading
40  *
41  * But....
42  *
43  *    When gcrypt >= 1.6.0 we must not initialize gcrypt threading
44  *    because gcrypt will do that itself.
45  *
46  * So we need to init gcrypt threading if
47  *
48  *   - gcrypt < 1.6.0
49  * AND
50  *   - gnutls < 2.12
51  *
52  */
53 
54 #if (defined(CONFIG_GNUTLS_GCRYPT) &&           \
55      (!defined(GNUTLS_VERSION_NUMBER) ||        \
56       (GNUTLS_VERSION_NUMBER < 0x020c00)) &&    \
57      (!defined(GCRYPT_VERSION_NUMBER) ||        \
58       (GCRYPT_VERSION_NUMBER < 0x010600)))
59 #define QCRYPTO_INIT_GCRYPT_THREADS
60 #else
61 #undef QCRYPTO_INIT_GCRYPT_THREADS
62 #endif
63 
64 #ifdef DEBUG_GNUTLS
65 static void qcrypto_gnutls_log(int level, const char *str)
66 {
67     fprintf(stderr, "%d: %s", level, str);
68 }
69 #endif
70 
71 #ifdef QCRYPTO_INIT_GCRYPT_THREADS
72 static int qcrypto_gcrypt_mutex_init(void **priv)
73 {                                                                             \
74     QemuMutex *lock = NULL;
75     lock = g_new0(QemuMutex, 1);
76     qemu_mutex_init(lock);
77     *priv = lock;
78     return 0;
79 }
80 
81 static int qcrypto_gcrypt_mutex_destroy(void **priv)
82 {
83     QemuMutex *lock = *priv;
84     qemu_mutex_destroy(lock);
85     g_free(lock);
86     return 0;
87 }
88 
89 static int qcrypto_gcrypt_mutex_lock(void **priv)
90 {
91     QemuMutex *lock = *priv;
92     qemu_mutex_lock(lock);
93     return 0;
94 }
95 
96 static int qcrypto_gcrypt_mutex_unlock(void **priv)
97 {
98     QemuMutex *lock = *priv;
99     qemu_mutex_unlock(lock);
100     return 0;
101 }
102 
103 static struct gcry_thread_cbs qcrypto_gcrypt_thread_impl = {
104     (GCRY_THREAD_OPTION_PTHREAD | (GCRY_THREAD_OPTION_VERSION << 8)),
105     NULL,
106     qcrypto_gcrypt_mutex_init,
107     qcrypto_gcrypt_mutex_destroy,
108     qcrypto_gcrypt_mutex_lock,
109     qcrypto_gcrypt_mutex_unlock,
110     NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
111 };
112 #endif /* QCRYPTO_INIT_GCRYPT */
113 
114 int qcrypto_init(Error **errp)
115 {
116     int ret;
117     ret = gnutls_global_init();
118     if (ret < 0) {
119         error_setg(errp,
120                    "Unable to initialize GNUTLS library: %s",
121                    gnutls_strerror(ret));
122         return -1;
123     }
124 #ifdef DEBUG_GNUTLS
125     gnutls_global_set_log_level(10);
126     gnutls_global_set_log_function(qcrypto_gnutls_log);
127 #endif
128 
129 #ifdef CONFIG_GNUTLS_GCRYPT
130     if (!gcry_check_version(GCRYPT_VERSION)) {
131         error_setg(errp, "Unable to initialize gcrypt");
132         return -1;
133     }
134 #ifdef QCRYPTO_INIT_GCRYPT_THREADS
135     gcry_control(GCRYCTL_SET_THREAD_CBS, &qcrypto_gcrypt_thread_impl);
136 #endif /* QCRYPTO_INIT_GCRYPT_THREADS */
137     gcry_control(GCRYCTL_INITIALIZATION_FINISHED, 0);
138 #endif
139 
140     return 0;
141 }
142 
143 #else /* ! CONFIG_GNUTLS */
144 
145 int qcrypto_init(Error **errp G_GNUC_UNUSED)
146 {
147     return 0;
148 }
149 
150 #endif /* ! CONFIG_GNUTLS */
151