xref: /openbmc/qemu/crypto/init.c (revision b86caf7a)
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 "qemu/osdep.h"
22 #include "crypto/init.h"
23 #include "qapi/error.h"
24 #include "qemu/thread.h"
25 
26 #ifdef CONFIG_GNUTLS
27 #include <gnutls/gnutls.h>
28 #include <gnutls/crypto.h>
29 #endif
30 
31 #ifdef CONFIG_GCRYPT
32 #include <gcrypt.h>
33 #endif
34 
35 #include "crypto/random.h"
36 
37 /* #define DEBUG_GNUTLS */
38 
39 /*
40  * If GNUTLS is built against GCrypt then
41  *
42  *  - When GNUTLS >= 2.12, we must not initialize gcrypt threading
43  *    because GNUTLS will do that itself
44  *  - When GNUTLS < 2.12 we must always initialize gcrypt threading
45  *  - When GNUTLS is disabled we must always initialize gcrypt threading
46  *
47  * But....
48  *
49  *    When gcrypt >= 1.6.0 we must not initialize gcrypt threading
50  *    because gcrypt will do that itself.
51  *
52  * So we need to init gcrypt threading if
53  *
54  *   - gcrypt < 1.6.0
55  * AND
56  *      - gnutls < 2.12
57  *   OR
58  *      - gnutls is disabled
59  *
60  */
61 
62 #if (defined(CONFIG_GCRYPT) &&                  \
63      (!defined(CONFIG_GNUTLS) ||                \
64      (LIBGNUTLS_VERSION_NUMBER < 0x020c00)) &&    \
65      (!defined(GCRYPT_VERSION_NUMBER) ||        \
66       (GCRYPT_VERSION_NUMBER < 0x010600)))
67 #define QCRYPTO_INIT_GCRYPT_THREADS
68 #else
69 #undef QCRYPTO_INIT_GCRYPT_THREADS
70 #endif
71 
72 #ifdef DEBUG_GNUTLS
73 static void qcrypto_gnutls_log(int level, const char *str)
74 {
75     fprintf(stderr, "%d: %s", level, str);
76 }
77 #endif
78 
79 #ifdef QCRYPTO_INIT_GCRYPT_THREADS
80 static int qcrypto_gcrypt_mutex_init(void **priv)
81 {                                                                             \
82     QemuMutex *lock = NULL;
83     lock = g_new0(QemuMutex, 1);
84     qemu_mutex_init(lock);
85     *priv = lock;
86     return 0;
87 }
88 
89 static int qcrypto_gcrypt_mutex_destroy(void **priv)
90 {
91     QemuMutex *lock = *priv;
92     qemu_mutex_destroy(lock);
93     g_free(lock);
94     return 0;
95 }
96 
97 static int qcrypto_gcrypt_mutex_lock(void **priv)
98 {
99     QemuMutex *lock = *priv;
100     qemu_mutex_lock(lock);
101     return 0;
102 }
103 
104 static int qcrypto_gcrypt_mutex_unlock(void **priv)
105 {
106     QemuMutex *lock = *priv;
107     qemu_mutex_unlock(lock);
108     return 0;
109 }
110 
111 static struct gcry_thread_cbs qcrypto_gcrypt_thread_impl = {
112     (GCRY_THREAD_OPTION_PTHREAD | (GCRY_THREAD_OPTION_VERSION << 8)),
113     NULL,
114     qcrypto_gcrypt_mutex_init,
115     qcrypto_gcrypt_mutex_destroy,
116     qcrypto_gcrypt_mutex_lock,
117     qcrypto_gcrypt_mutex_unlock,
118     NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
119 };
120 #endif /* QCRYPTO_INIT_GCRYPT */
121 
122 int qcrypto_init(Error **errp)
123 {
124 #ifdef QCRYPTO_INIT_GCRYPT_THREADS
125     gcry_control(GCRYCTL_SET_THREAD_CBS, &qcrypto_gcrypt_thread_impl);
126 #endif /* QCRYPTO_INIT_GCRYPT_THREADS */
127 
128 #ifdef CONFIG_GNUTLS
129     int ret;
130     ret = gnutls_global_init();
131     if (ret < 0) {
132         error_setg(errp,
133                    "Unable to initialize GNUTLS library: %s",
134                    gnutls_strerror(ret));
135         return -1;
136     }
137 #ifdef DEBUG_GNUTLS
138     gnutls_global_set_log_level(10);
139     gnutls_global_set_log_function(qcrypto_gnutls_log);
140 #endif
141 #endif
142 
143 #ifdef CONFIG_GCRYPT
144     if (!gcry_check_version(GCRYPT_VERSION)) {
145         error_setg(errp, "Unable to initialize gcrypt");
146         return -1;
147     }
148     gcry_control(GCRYCTL_INITIALIZATION_FINISHED, 0);
149 #endif
150 
151     if (qcrypto_random_init(errp) < 0) {
152         return -1;
153     }
154 
155     return 0;
156 }
157