xref: /openbmc/qemu/crypto/init.c (revision 8692aa29)
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 /* #define DEBUG_GNUTLS */
36 
37 /*
38  * If GNUTLS is built against GCrypt then
39  *
40  *  - When GNUTLS >= 2.12, we must not initialize gcrypt threading
41  *    because GNUTLS will do that itself
42  *  - When GNUTLS < 2.12 we must always initialize gcrypt threading
43  *  - When GNUTLS is disabled we must always initialize gcrypt threading
44  *
45  * But....
46  *
47  *    When gcrypt >= 1.6.0 we must not initialize gcrypt threading
48  *    because gcrypt will do that itself.
49  *
50  * So we need to init gcrypt threading if
51  *
52  *   - gcrypt < 1.6.0
53  * AND
54  *      - gnutls < 2.12
55  *   OR
56  *      - gnutls is disabled
57  *
58  */
59 
60 #if (defined(CONFIG_GCRYPT) &&                  \
61      (!defined(CONFIG_GNUTLS) ||                \
62       !defined(GNUTLS_VERSION_NUMBER) ||       \
63       (GNUTLS_VERSION_NUMBER < 0x020c00)) &&    \
64      (!defined(GCRYPT_VERSION_NUMBER) ||        \
65       (GCRYPT_VERSION_NUMBER < 0x010600)))
66 #define QCRYPTO_INIT_GCRYPT_THREADS
67 #else
68 #undef QCRYPTO_INIT_GCRYPT_THREADS
69 #endif
70 
71 #ifdef DEBUG_GNUTLS
72 static void qcrypto_gnutls_log(int level, const char *str)
73 {
74     fprintf(stderr, "%d: %s", level, str);
75 }
76 #endif
77 
78 #ifdef QCRYPTO_INIT_GCRYPT_THREADS
79 static int qcrypto_gcrypt_mutex_init(void **priv)
80 {                                                                             \
81     QemuMutex *lock = NULL;
82     lock = g_new0(QemuMutex, 1);
83     qemu_mutex_init(lock);
84     *priv = lock;
85     return 0;
86 }
87 
88 static int qcrypto_gcrypt_mutex_destroy(void **priv)
89 {
90     QemuMutex *lock = *priv;
91     qemu_mutex_destroy(lock);
92     g_free(lock);
93     return 0;
94 }
95 
96 static int qcrypto_gcrypt_mutex_lock(void **priv)
97 {
98     QemuMutex *lock = *priv;
99     qemu_mutex_lock(lock);
100     return 0;
101 }
102 
103 static int qcrypto_gcrypt_mutex_unlock(void **priv)
104 {
105     QemuMutex *lock = *priv;
106     qemu_mutex_unlock(lock);
107     return 0;
108 }
109 
110 static struct gcry_thread_cbs qcrypto_gcrypt_thread_impl = {
111     (GCRY_THREAD_OPTION_PTHREAD | (GCRY_THREAD_OPTION_VERSION << 8)),
112     NULL,
113     qcrypto_gcrypt_mutex_init,
114     qcrypto_gcrypt_mutex_destroy,
115     qcrypto_gcrypt_mutex_lock,
116     qcrypto_gcrypt_mutex_unlock,
117     NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
118 };
119 #endif /* QCRYPTO_INIT_GCRYPT */
120 
121 int qcrypto_init(Error **errp)
122 {
123 #ifdef CONFIG_GNUTLS
124     int ret;
125     ret = gnutls_global_init();
126     if (ret < 0) {
127         error_setg(errp,
128                    "Unable to initialize GNUTLS library: %s",
129                    gnutls_strerror(ret));
130         return -1;
131     }
132 #ifdef DEBUG_GNUTLS
133     gnutls_global_set_log_level(10);
134     gnutls_global_set_log_function(qcrypto_gnutls_log);
135 #endif
136 #endif
137 
138 #ifdef CONFIG_GCRYPT
139     if (!gcry_check_version(GCRYPT_VERSION)) {
140         error_setg(errp, "Unable to initialize gcrypt");
141         return -1;
142     }
143 #ifdef QCRYPTO_INIT_GCRYPT_THREADS
144     gcry_control(GCRYCTL_SET_THREAD_CBS, &qcrypto_gcrypt_thread_impl);
145 #endif /* QCRYPTO_INIT_GCRYPT_THREADS */
146     gcry_control(GCRYCTL_INITIALIZATION_FINISHED, 0);
147 #endif
148 
149     return 0;
150 }
151