crypto_gcrypt.c

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/*
     This file is part of GNUnet.
     Copyright (C) 2001-2026 GNUnet e.V.
 
     GNUnet is free software: you can redistribute it and/or modify it
     under the terms of the GNU Affero General Public License as published
     by the Free Software Foundation, either version 3 of the License,
     or (at your option) any later version.
 
     GNUnet is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Affero General Public License for more details.
 
     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
     SPDX-License-Identifier: AGPL3.0-or-later
 
 */
 
#include "platform.h"
#include "gnunet_util_lib.h"
#include <gcrypt.h>
 
 
static void *
w_malloc (size_t n)
{
  return calloc (n, 1);
}
 
 
static int
w_check (const void *p)
{
  (void) p;
  return 0; /* not secure memory */
}
 
 
void
GNUNET_CRYPTO_gcrypt_init (void);
 
void __attribute__ ((constructor))
GNUNET_CRYPTO_gcrypt_init (void)
{
  gcry_error_t rc;
 
  if (! gcry_check_version (NEED_LIBGCRYPT_VERSION))
  {
    fprintf (
      stderr,
      _ ("libgcrypt has not the expected version (version %s is required).\n"),
      NEED_LIBGCRYPT_VERSION);
    GNUNET_assert (0);
  }
  /* set custom allocators */
  gcry_set_allocation_handler (&w_malloc, &w_malloc, &w_check, &realloc, &free);
  /* Disable use of secure memory */
  if ((rc = gcry_control (GCRYCTL_DISABLE_SECMEM, 0)))
    fprintf (stderr,
             "Failed to set libgcrypt option %s: %s\n",
             "DISABLE_SECMEM",
             gcry_strerror (rc));
  /* Otherwise gnunet-ecc takes forever to complete, besides
     we are fine with "just" using GCRY_STRONG_RANDOM */
  if ((rc = gcry_control (GCRYCTL_ENABLE_QUICK_RANDOM, 0)))
    fprintf (stderr,
             "Failed to set libgcrypt option %s: %s\n",
             "ENABLE_QUICK_RANDOM",
             gcry_strerror (rc));
  gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
}
 
 
void
GNUNET_CRYPTO_gcrypt_fini (void);
 
void __attribute__ ((destructor))
GNUNET_CRYPTO_gcrypt_fini (void)
{
  gcry_set_progress_handler (NULL, NULL);
#ifdef GCRYCTL_CLOSE_RANDOM_DEVICE
  (void) gcry_control (GCRYCTL_CLOSE_RANDOM_DEVICE, 0);
#endif
}
 
 
/* end of crypto_gcrypt.c */