libextra/gnutls_extra.c

   1 /*
   2  * Copyright (C) 2001, 2004, 2005, 2007, 2008 Free Software Foundation
   3  *
   4  * Author: Nikos Mavrogiannopoulos
   5  *
   6  * This file is part of GNUTLS-EXTRA.
   7  *
   8  * GNUTLS-EXTRA is free software: you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation, either version 3 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * GNUTLS-EXTRA is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include <gnutls_int.h>
  23 #include <gnutls_errors.h>
  24 #include <gnutls_extensions.h>
  25 #include <gnutls_algorithms.h>
  26 #ifdef USE_LZO
  27 # ifdef USE_MINILZO
  28 #  include "minilzo/minilzo.h"
  29 # elif HAVE_LZO_LZO1X_H
  30 #  include <lzo/lzo1x.h>
  31 # elif HAVE_LZO1X_H
  32 #  include <lzo1x.h>
  33 # endif
  34 #endif
  35
  36
  37 /* the number of the compression algorithms available in the compression
  38  * structure.
  39  */
  40 extern int _gnutls_comp_algorithms_size;
  41
  42 /* Functions in gnutls that have not been initialized.
  43  */
  44 #ifdef USE_LZO
  45 typedef int (*LZO_FUNC) ();
  46 extern LZO_FUNC _gnutls_lzo1x_decompress_safe;
  47 extern LZO_FUNC _gnutls_lzo1x_1_compress;
  48
  49 extern gnutls_compression_entry _gnutls_compression_algorithms[];
  50
  51 static int
  52 _gnutls_add_lzo_comp (void)
  53 {
  54   int i;
  55
  56   /* find the last element */
  57   for (i = 0; i < _gnutls_comp_algorithms_size; i++)
  58     {
  59       if (_gnutls_compression_algorithms[i].name == NULL)
  60         break;
  61     }
  62
  63   if (_gnutls_compression_algorithms[i].name == NULL
  64       && (i < _gnutls_comp_algorithms_size - 1))
  65     {
  66       _gnutls_compression_algorithms[i].name = "GNUTLS_COMP_LZO";
  67       _gnutls_compression_algorithms[i].id = GNUTLS_COMP_LZO;
  68       _gnutls_compression_algorithms[i].num = 0xf2;
  69
  70       _gnutls_compression_algorithms[i + 1].name = 0;
  71
  72       /* Now enable the lzo functions: */
  73       _gnutls_lzo1x_decompress_safe = lzo1x_decompress_safe;
  74       _gnutls_lzo1x_1_compress = lzo1x_1_compress;
  75
  76       return 0;                 /* ok */
  77     }
  78
  79
  80   return GNUTLS_E_MEMORY_ERROR;
  81 }
  82 #endif
  83
  84 static int _gnutls_init_extra = 0;
  85
  86 /**
  87   * gnutls_global_init_extra - This function initializes the global state of gnutls-extra
  88   *
  89   * This function initializes the global state of gnutls-extra library
  90   * to defaults.  Returns zero on success.
  91   *
  92   * Note that gnutls_global_init() has to be called before this
  93   * function.  If this function is not called then the gnutls-extra
  94   * library will not be usable.
  95   *
  96   **/
  97 int
  98 gnutls_global_init_extra (void)
  99 {
 100   /* If the version of libgnutls != version of
 101    * libextra, then do not initialize the library.
 102    * This is because it may break things.
 103    */
 104   if (strcmp (gnutls_check_version (NULL), VERSION) != 0)
 105     {
 106       return GNUTLS_E_LIBRARY_VERSION_MISMATCH;
 107     }
 108
 109   _gnutls_init_extra++;
 110
 111   if (_gnutls_init_extra != 1)
 112     {
 113       return 0;
 114     }
 115
 116   /* Initialize the LZO library
 117    */
 118 #ifdef USE_LZO
 119   {
 120     int ret;
 121
 122     if (lzo_init () != LZO_E_OK)
 123       {
 124         return GNUTLS_E_LZO_INIT_FAILED;
 125       }
 126
 127     /* Add the LZO compression method in the list of compression
 128      * methods.
 129      */
 130     ret = _gnutls_add_lzo_comp ();
 131     if (ret < 0)
 132       {
 133         gnutls_assert ();
 134         return ret;
 135       }
 136   }
 137 #endif
 138
 139   return 0;
 140 }
 141
 142 #include <strverscmp.h>
 143
 144 /**
 145  * gnutls_extra_check_version - This function checks the library's version
 146  * @req_version: the version to check
 147  *
 148  * Check that the version of the gnutls-extra library is at minimum
 149  * the requested one and return the version string; return NULL if the
 150  * condition is not satisfied.  If a NULL is passed to this function,
 151  * no check is done, but the version string is simply returned.
 152  *
 153  **/
 154 const char *
 155 gnutls_extra_check_version (const char *req_version)
 156 {
 157   if (!req_version || strverscmp (req_version, VERSION) <= 0)
 158     return VERSION;
 159
 160   return NULL;
 161 }