src/charon-tkm/src/tkm/tkm_diffie_hellman.c

   1 /*
   2  * Copyrigth (C) 2012 Reto Buerki
   3  * Copyright (C) 2012 Adrian-Ken Rueegsegger
   4  * Hochschule fuer Technik Rapperswil
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2 of the License, or (at your
   9  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * for more details.
  15  */
  16
  17 #include <tkm/client.h>
  18 #include <tkm/constants.h>
  19
  20 #include "tkm_diffie_hellman.h"
  21
  22 #include <utils/debug.h>
  23
  24 typedef struct private_tkm_diffie_hellman_t private_tkm_diffie_hellman_t;
  25
  26 /**
  27  * Private data of a tkm_diffie_hellman_t object.
  28  */
  29 struct private_tkm_diffie_hellman_t {
  30         /**
  31          * Public tkm_diffie_hellman_t interface.
  32          */
  33         tkm_diffie_hellman_t public;
  34
  35         /**
  36          * Diffie Hellman group number.
  37          */
  38         u_int16_t group;
  39
  40         /**
  41          * Diffie Hellman public value.
  42          */
  43         dh_pubvalue_type pubvalue;
  44 };
  45
  46 METHOD(diffie_hellman_t, get_my_public_value, void,
  47         private_tkm_diffie_hellman_t *this, chunk_t *value)
  48 {
  49         *value = chunk_alloc(this->pubvalue.size);
  50         memcpy(value->ptr, &this->pubvalue.data, value->len);
  51 }
  52
  53 METHOD(diffie_hellman_t, get_shared_secret, status_t,
  54         private_tkm_diffie_hellman_t *this, chunk_t *secret)
  55 {
  56         dh_key_type shared_secret;
  57         if (ike_dh_get_shared_secret(1, &shared_secret) != TKM_OK)
  58         {
  59                 return FAILED;
  60         }
  61
  62         *secret = chunk_alloc(shared_secret.size);
  63         memcpy(secret->ptr, &shared_secret.data, secret->len);
  64         return SUCCESS;
  65 }
  66
  67
  68 METHOD(diffie_hellman_t, set_other_public_value, void,
  69         private_tkm_diffie_hellman_t *this, chunk_t value)
  70 {
  71         // TODO: unvoid this function
  72
  73         dh_pubvalue_type othervalue;
  74         othervalue.size = value.len;
  75         memcpy(&othervalue.data, value.ptr, value.len);
  76
  77         ike_dh_generate_key(1, othervalue);
  78 }
  79
  80 METHOD(diffie_hellman_t, get_dh_group, diffie_hellman_group_t,
  81         private_tkm_diffie_hellman_t *this)
  82 {
  83         return this->group;
  84 }
  85
  86 METHOD(diffie_hellman_t, destroy, void,
  87         private_tkm_diffie_hellman_t *this)
  88 {
  89         // TODO: unvoid this function
  90
  91         free(this);
  92         if (ike_dh_reset(1) != TKM_OK)
  93         {
  94                 DBG1(DBG_LIB, "resetting DH context 1 failed");
  95         }
  96 }
  97
  98 /*
  99  * Described in header.
 100  */
 101 tkm_diffie_hellman_t *tkm_diffie_hellman_create(diffie_hellman_group_t group)
 102 {
 103         private_tkm_diffie_hellman_t *this;
 104
 105         INIT(this,
 106                 .public = {
 107                         .dh = {
 108                                 .get_shared_secret = _get_shared_secret,
 109                                 .set_other_public_value = _set_other_public_value,
 110                                 .get_my_public_value = _get_my_public_value,
 111                                 .get_dh_group = _get_dh_group,
 112                                 .destroy = _destroy,
 113                         },
 114                 },
 115         );
 116
 117         if (ike_dh_create(1, group, &this->pubvalue) != TKM_OK)
 118         {
 119                 free(this);
 120                 return NULL;
 121         }
 122
 123         this->group = group;
 124
 125         return &this->public;
 126 }