lib/auth_anon.c

   1 /*
   2  * Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2009, 2010 Free
   3  * Software Foundation, Inc.
   4  *
   5  * Author: Nikos Mavrogiannopoulos
   6  *
   7  * This file is part of GnuTLS.
   8  *
   9  * The GnuTLS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1 of
  12  * the License, or (at your option) any later version.
  13  *
  14  * This library 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  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  22  * USA
  23  *
  24  */
  25
  26 /* This file contains the Anonymous Diffie-Hellman key exchange part of
  27  * the anonymous authentication. The functions here are used in the
  28  * handshake.
  29  */
  30
  31 #include <gnutls_int.h>
  32
  33 #ifdef ENABLE_ANON
  34
  35 #include "gnutls_auth.h"
  36 #include "gnutls_errors.h"
  37 #include "gnutls_dh.h"
  38 #include "auth_anon.h"
  39 #include "gnutls_num.h"
  40 #include "gnutls_mpi.h"
  41 #include <gnutls_state.h>
  42 #include <auth_dh_common.h>
  43
  44 static int gen_anon_server_kx (gnutls_session_t, opaque **);
  45 static int proc_anon_client_kx (gnutls_session_t, opaque *, size_t);
  46 static int proc_anon_server_kx (gnutls_session_t, opaque *, size_t);
  47
  48 const mod_auth_st anon_auth_struct = {
  49   "ANON",
  50   NULL,
  51   NULL,
  52   gen_anon_server_kx,
  53   _gnutls_gen_dh_common_client_kx,      /* this can be shared */
  54   NULL,
  55   NULL,
  56
  57   NULL,
  58   NULL,                         /* certificate */
  59   proc_anon_server_kx,
  60   proc_anon_client_kx,
  61   NULL,
  62   NULL
  63 };
  64
  65 static int
  66 gen_anon_server_kx (gnutls_session_t session, opaque ** data)
  67 {
  68   bigint_t g, p;
  69   const bigint_t *mpis;
  70   int ret;
  71   gnutls_dh_params_t dh_params;
  72   gnutls_anon_server_credentials_t cred;
  73
  74   cred = (gnutls_anon_server_credentials_t)
  75     _gnutls_get_cred (session->key, GNUTLS_CRD_ANON, NULL);
  76   if (cred == NULL)
  77     {
  78       gnutls_assert ();
  79       return GNUTLS_E_INSUFFICIENT_CREDENTIALS;
  80     }
  81
  82   dh_params =
  83     _gnutls_get_dh_params (cred->dh_params, cred->params_func, session);
  84   mpis = _gnutls_dh_params_to_mpi (dh_params);
  85   if (mpis == NULL)
  86     {
  87       gnutls_assert ();
  88       return GNUTLS_E_NO_TEMPORARY_DH_PARAMS;
  89     }
  90
  91   p = mpis[0];
  92   g = mpis[1];
  93
  94   if ((ret =
  95        _gnutls_auth_info_set (session, GNUTLS_CRD_ANON,
  96                               sizeof (anon_auth_info_st), 1)) < 0)
  97     {
  98       gnutls_assert ();
  99       return ret;
 100     }
 101
 102   _gnutls_dh_set_group (session, g, p);
 103
 104   ret = _gnutls_dh_common_print_server_kx (session, g, p, data, 0);
 105   if (ret < 0)
 106     {
 107       gnutls_assert ();
 108     }
 109
 110   return ret;
 111 }
 112
 113
 114 static int
 115 proc_anon_client_kx (gnutls_session_t session, opaque * data,
 116                      size_t _data_size)
 117 {
 118   gnutls_anon_server_credentials_t cred;
 119   int ret;
 120   bigint_t p, g;
 121   gnutls_dh_params_t dh_params;
 122   const bigint_t *mpis;
 123
 124   cred = (gnutls_anon_server_credentials_t)
 125     _gnutls_get_cred (session->key, GNUTLS_CRD_ANON, NULL);
 126   if (cred == NULL)
 127     {
 128       gnutls_assert ();
 129       return GNUTLS_E_INSUFFICIENT_CREDENTIALS;
 130     }
 131
 132   dh_params =
 133     _gnutls_get_dh_params (cred->dh_params, cred->params_func, session);
 134   mpis = _gnutls_dh_params_to_mpi (dh_params);
 135   if (mpis == NULL)
 136     {
 137       gnutls_assert ();
 138       return GNUTLS_E_NO_TEMPORARY_DH_PARAMS;
 139     }
 140
 141   p = mpis[0];
 142   g = mpis[1];
 143
 144   ret = _gnutls_proc_dh_common_client_kx (session, data, _data_size, g, p);
 145
 146   return ret;
 147
 148 }
 149
 150 int
 151 proc_anon_server_kx (gnutls_session_t session, opaque * data,
 152                      size_t _data_size)
 153 {
 154
 155   int ret;
 156
 157   /* set auth_info */
 158   if ((ret =
 159        _gnutls_auth_info_set (session, GNUTLS_CRD_ANON,
 160                               sizeof (anon_auth_info_st), 1)) < 0)
 161     {
 162       gnutls_assert ();
 163       return ret;
 164     }
 165
 166   ret = _gnutls_proc_dh_common_server_kx (session, data, _data_size, 0);
 167   if (ret < 0)
 168     {
 169       gnutls_assert ();
 170       return ret;
 171     }
 172
 173   return 0;
 174 }
 175
 176 #endif /* ENABLE_ANON */