libextra/gnutls_extra.c

   1 /*
   2  * Copyright (C) 2001, 2004, 2005, 2007, 2008, 2009, 2010 Free Software
   3  * Foundation, Inc.
   4  *
   5  * Author: Nikos Mavrogiannopoulos
   6  *
   7  * This file is part of GNUTLS-EXTRA.
   8  *
   9  * GNUTLS-EXTRA is free software: you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License as
  11  * published by the Free Software Foundation, either version 3 of the
  12  * License, or (at your option) any later version.
  13  *
  14  * GNUTLS-EXTRA is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program.  If not, see
  21  * <http://www.gnu.org/licenses/>.
  22  */
  23
  24 #include <gnutls_int.h>
  25 #include <gnutls_errors.h>
  26 #include <gnutls_extensions.h>
  27 #include <gnutls_algorithms.h>
  28 #include <ext_inner_application.h>
  29 #ifdef USE_LZO
  30 # ifdef USE_MINILZO
  31 #  include "minilzo/minilzo.h"
  32 # elif HAVE_LZO_LZO1X_H
  33 #  include <lzo/lzo1x.h>
  34 # elif HAVE_LZO1X_H
  35 #  include <lzo1x.h>
  36 # endif
  37 #endif
  38 #include <gnutls/extra.h>
  39
  40 #ifdef USE_LZO
  41 #include <gnutls_compress.h>
  42
  43 /* the number of the compression algorithms available in the compression
  44  * structure.
  45  */
  46 extern int _gnutls_comp_algorithms_size;
  47
  48 typedef int (*LZO_FUNC) ();
  49 extern LZO_FUNC _gnutls_lzo1x_decompress_safe;
  50 extern LZO_FUNC _gnutls_lzo1x_1_compress;
  51
  52 extern gnutls_compression_entry _gnutls_compression_algorithms[];
  53
  54 static int
  55 _gnutls_add_lzo_comp (void)
  56 {
  57   int i;
  58
  59   /* find the last element */
  60   for (i = 0; i < _gnutls_comp_algorithms_size; i++)
  61     {
  62       if (_gnutls_compression_algorithms[i].name == NULL)
  63         break;
  64     }
  65
  66   if (_gnutls_compression_algorithms[i].name == NULL
  67       && (i < _gnutls_comp_algorithms_size - 1))
  68     {
  69       _gnutls_compression_algorithms[i].name = "GNUTLS_COMP_LZO";
  70       _gnutls_compression_algorithms[i].id = GNUTLS_COMP_LZO;
  71       _gnutls_compression_algorithms[i].num = 0xf2;
  72
  73       _gnutls_compression_algorithms[i + 1].name = 0;
  74
  75       /* Now enable the lzo functions: */
  76       _gnutls_lzo1x_decompress_safe = lzo1x_decompress_safe;
  77       _gnutls_lzo1x_1_compress = lzo1x_1_compress;
  78
  79       return 0;                 /* ok */
  80     }
  81
  82
  83   return GNUTLS_E_MEMORY_ERROR;
  84 }
  85 #endif
  86
  87 static int _gnutls_init_extra = 0;
  88
  89 /**
  90  * gnutls_global_init_extra - initializes the global state of gnutls-extra
  91  *
  92  * This function initializes the global state of gnutls-extra library
  93  * to defaults.
  94  *
  95  * Note that gnutls_global_init() has to be called before this
  96  * function.  If this function is not called then the gnutls-extra
  97  * library will not be usable.
  98  *
  99  * This function is not thread safe, see the discussion for
 100  * gnutls_global_init() on how to deal with that.
 101  *
 102  * Returns: On success, %GNUTLS_E_SUCCESS (zero) is returned,
 103  *   otherwise an error code is returned.
 104  **/
 105 int
 106 gnutls_global_init_extra (void)
 107 {
 108   int ret;
 109
 110   /* If the version of libgnutls != version of
 111    * libextra, then do not initialize the library.
 112    * This is because it may break things.
 113    */
 114   if (strcmp (gnutls_check_version (NULL), VERSION) != 0)
 115     {
 116       return GNUTLS_E_LIBRARY_VERSION_MISMATCH;
 117     }
 118
 119   _gnutls_init_extra++;
 120
 121   if (_gnutls_init_extra != 1)
 122     return 0;
 123
 124   ret = gnutls_ext_register (GNUTLS_EXTENSION_INNER_APPLICATION,
 125                              "INNER_APPLICATION",
 126                              GNUTLS_EXT_TLS,
 127                              _gnutls_inner_application_recv_params,
 128                              _gnutls_inner_application_send_params);
 129   if (ret != GNUTLS_E_SUCCESS)
 130     return ret;
 131
 132   /* Initialize the LZO library
 133    */
 134 #ifdef USE_LZO
 135   if (lzo_init () != LZO_E_OK)
 136     return GNUTLS_E_LZO_INIT_FAILED;
 137
 138   /* Add the LZO compression method in the list of compression
 139    * methods.
 140    */
 141   ret = _gnutls_add_lzo_comp ();
 142   if (ret < 0)
 143     {
 144       gnutls_assert ();
 145       return ret;
 146     }
 147 #endif
 148
 149   return 0;
 150 }
 151
 152 /**
 153  * gnutls_extra_check_version - checks the libgnutls-extra version
 154  * @req_version: version string to compare with, or %NULL.
 155  *
 156  * Check GnuTLS Extra Library version.
 157  *
 158  * See %GNUTLS_EXTRA_VERSION for a suitable @req_version string.
 159  *
 160  * Return value: Check that the version of the library is at
 161  *   minimum the one given as a string in @req_version and return the
 162  *   actual version string of the library; return %NULL if the
 163  *   condition is not met.  If %NULL is passed to this function no
 164  *   check is done and only the version string is returned.
 165  **/
 166 const char *
 167 gnutls_extra_check_version (const char *req_version)
 168 {
 169   if (!req_version || strverscmp (req_version, VERSION) <= 0)
 170     return VERSION;
 171
 172   return NULL;
 173 }