xref: /openbmc/qemu/crypto/init.c (revision b969526a)
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 #endif
28 
29 #ifdef CONFIG_GCRYPT
30 #include <gcrypt.h>
31 #endif
32 
33 /* #define DEBUG_GNUTLS */
34 
35 /*
36  * If GNUTLS is built against GCrypt then
37  *
38  *  - When GNUTLS >= 2.12, we must not initialize gcrypt threading
39  *    because GNUTLS will do that itself
40  *  - When GNUTLS < 2.12 we must always initialize gcrypt threading
41  *  - When GNUTLS is disabled we must always initialize gcrypt threading
42  *
43  * But....
44  *
45  *    When gcrypt >= 1.6.0 we must not initialize gcrypt threading
46  *    because gcrypt will do that itself.
47  *
48  * So we need to init gcrypt threading if
49  *
50  *   - gcrypt < 1.6.0
51  * AND
52  *      - gnutls < 2.12
53  *   OR
54  *      - gnutls is disabled
55  *
56  */
57 
58 #if (defined(CONFIG_GCRYPT) &&                  \
59      (!defined(CONFIG_GNUTLS) ||                \
60       !defined(GNUTLS_VERSION_NUMBER) ||       \
61       (GNUTLS_VERSION_NUMBER < 0x020c00)) &&    \
62      (!defined(GCRYPT_VERSION_NUMBER) ||        \
63       (GCRYPT_VERSION_NUMBER < 0x010600)))
64 #define QCRYPTO_INIT_GCRYPT_THREADS
65 #else
66 #undef QCRYPTO_INIT_GCRYPT_THREADS
67 #endif
68 
69 #ifdef DEBUG_GNUTLS
70 static void qcrypto_gnutls_log(int level, const char *str)
71 {
72     fprintf(stderr, "%d: %s", level, str);
73 }
74 #endif
75 
76 #ifdef QCRYPTO_INIT_GCRYPT_THREADS
77 static int qcrypto_gcrypt_mutex_init(void **priv)
78 {                                                                             \
79     QemuMutex *lock = NULL;
80     lock = g_new0(QemuMutex, 1);
81     qemu_mutex_init(lock);
82     *priv = lock;
83     return 0;
84 }
85 
86 static int qcrypto_gcrypt_mutex_destroy(void **priv)
87 {
88     QemuMutex *lock = *priv;
89     qemu_mutex_destroy(lock);
90     g_free(lock);
91     return 0;
92 }
93 
94 static int qcrypto_gcrypt_mutex_lock(void **priv)
95 {
96     QemuMutex *lock = *priv;
97     qemu_mutex_lock(lock);
98     return 0;
99 }
100 
101 static int qcrypto_gcrypt_mutex_unlock(void **priv)
102 {
103     QemuMutex *lock = *priv;
104     qemu_mutex_unlock(lock);
105     return 0;
106 }
107 
108 static struct gcry_thread_cbs qcrypto_gcrypt_thread_impl = {
109     (GCRY_THREAD_OPTION_PTHREAD | (GCRY_THREAD_OPTION_VERSION << 8)),
110     NULL,
111     qcrypto_gcrypt_mutex_init,
112     qcrypto_gcrypt_mutex_destroy,
113     qcrypto_gcrypt_mutex_lock,
114     qcrypto_gcrypt_mutex_unlock,
115     NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
116 };
117 #endif /* QCRYPTO_INIT_GCRYPT */
118 
119 int qcrypto_init(Error **errp)
120 {
121 #ifdef CONFIG_GNUTLS
122     int ret;
123     ret = gnutls_global_init();
124     if (ret < 0) {
125         error_setg(errp,
126                    "Unable to initialize GNUTLS library: %s",
127                    gnutls_strerror(ret));
128         return -1;
129     }
130 #ifdef DEBUG_GNUTLS
131     gnutls_global_set_log_level(10);
132     gnutls_global_set_log_function(qcrypto_gnutls_log);
133 #endif
134 #endif
135 
136 #ifdef CONFIG_GCRYPT
137     if (!gcry_check_version(GCRYPT_VERSION)) {
138         error_setg(errp, "Unable to initialize gcrypt");
139         return -1;
140     }
141 #ifdef QCRYPTO_INIT_GCRYPT_THREADS
142     gcry_control(GCRYCTL_SET_THREAD_CBS, &qcrypto_gcrypt_thread_impl);
143 #endif /* QCRYPTO_INIT_GCRYPT_THREADS */
144     gcry_control(GCRYCTL_INITIALIZATION_FINISHED, 0);
145 #endif
146 
147     return 0;
148 }
149