LXR qemu/crypto/init.c

   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
  73static 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
  80static 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
  89static 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
  97static int qcrypto_gcrypt_mutex_lock(void **priv)
  98{
  99    QemuMutex *lock = *priv;
 100    qemu_mutex_lock(lock);
 101    return 0;
 102}
 103
 104static int qcrypto_gcrypt_mutex_unlock(void **priv)
 105{
 106    QemuMutex *lock = *priv;
 107    qemu_mutex_unlock(lock);
 108    return 0;
 109}
 110
 111static 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
 122int 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