lib/random.c

   1 /*
   2  * Copyright (C) 2008, 2010 Free Software Foundation, Inc.
   3  *
   4  * Author: Nikos Mavrogiannopoulos
   5  *
   6  * This file is part of GnuTLS.
   7  *
   8  * The GnuTLS is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public License
  10  * as published by the Free Software Foundation; either version 2.1 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  21  * USA
  22  *
  23  */
  24
  25 /* This file handles all the internal functions that cope with random data.
  26  */
  27
  28 #include <gnutls_int.h>
  29 #include <gnutls_errors.h>
  30 #include <random.h>
  31
  32 static void *rnd_ctx;
  33
  34 int
  35 _gnutls_rnd_init (void)
  36 {
  37   if (_gnutls_rnd_ops.init != NULL)
  38     {
  39       if (_gnutls_rnd_ops.init (&rnd_ctx) < 0)
  40         {
  41           gnutls_assert ();
  42           return GNUTLS_E_RANDOM_FAILED;
  43         }
  44     }
  45
  46   return 0;
  47 }
  48
  49 void
  50 _gnutls_rnd_deinit (void)
  51 {
  52   if (_gnutls_rnd_ops.deinit != NULL)
  53     {
  54       _gnutls_rnd_ops.deinit (rnd_ctx);
  55     }
  56
  57   return;
  58 }
  59
  60 /**
  61  * gnutls_rnd:
  62  * @level: a security level
  63  * @data: place to store random bytes
  64  * @len: The requested size
  65  *
  66  * This function will generate random data and store it
  67  * to output buffer.
  68  *
  69  * Returns: Zero or a negative value on error.
  70  *
  71  **/
  72
  73 int
  74 gnutls_rnd (gnutls_rnd_level_t level, void *data, size_t len)
  75 {
  76   if (len > 0)
  77     {
  78       return _gnutls_rnd_ops.rnd (rnd_ctx, level, data, len);
  79     }
  80   return 0;
  81 }