Source/charon/transforms/diffie_hellman.h

   1 /**
   2  * @file diffie_hellman.h
   3  *
   4  * @brief Class to represent a diffie hellman exchange.
   5  *
   6  */
   7
   8 /*
   9  * Copyright (C) 2005 Jan Hutter, Martin Willi
  10  * Hochschule fuer Technik Rapperswil
  11  *
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the
  14  * Free Software Foundation; either version 2 of the License, or (at your
  15  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  19  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  */
  22
  23 #ifndef DIFFIE_HELLMAN_H_
  24 #define DIFFIE_HELLMAN_H_
  25
  26 #include "../types.h"
  27
  28 /**
  29  * Object representing a diffie hellman exchange
  30  *
  31  */
  32 typedef struct diffie_hellman_s diffie_hellman_t;
  33
  34 struct diffie_hellman_s {
  35
  36         /**
  37          * @brief Returns the shared secret of this diffie hellman exchange
  38          *
  39          * @warning Space for returned secret is allocated and has to get freed by the caller
  40          *
  41          * @param this                  calling diffie_hellman_t object
  42          * @param[out] secret   shared secret will be written into this chunk
  43          * @return
  44          *                                              - SUCCESS
  45          *                                              - FAILED if not both DH values are set
  46          *                                              - OUT_OF_RES if out of ressources
  47          */
  48         status_t (*get_shared_secret) (diffie_hellman_t *this, chunk_t *secret);
  49
  50         /**
  51          * @brief Sets the public value of partner
  52          *
  53          * @warning chunk gets copied
  54          *
  55          * @param this                  calling diffie_hellman_t object
  56          * @param public_value  public value of partner
  57          * @return
  58          *                                              - SUCCESS
  59          *                                              - OUT_OF_RES if out of ressources
  60          */
  61         status_t (*set_other_public_value) (diffie_hellman_t *this, chunk_t public_value);
  62
  63         /**
  64          * @brief Gets the public value of partner
  65          *
  66          * @warning chunk gets copied
  67          *
  68          * @param this                          calling diffie_hellman_t object
  69          * @param[out] public_value     public value of partner is stored at this location
  70          * @return
  71          *                                                      - SUCCESS
  72          *                                                      - OUT_OF_RES if out of ressources
  73          *                                                      - FAILED if other public value not set
  74          */
  75         status_t (*get_other_public_value) (diffie_hellman_t *this, chunk_t *public_value);
  76
  77         /**
  78          * @brief Gets the public value of caller
  79          *
  80          * @warning chunk gets copied
  81          *
  82          * @param this                          calling diffie_hellman_t object
  83          * @param[out] public_value     public value of caller is stored at this location
  84          * @return
  85          *                                                      - SUCCESS
  86          *                                                      - OUT_OF_RES if out of ressources
  87          */
  88         status_t (*get_my_public_value) (diffie_hellman_t *this, chunk_t *public_value);
  89
  90         /**
  91          * @brief Destroys an diffie_hellman_t object.
  92          *
  93          * @param this  diffie_hellman_t object to destroy
  94          * @return
  95          *                              SUCCESS in any case
  96          */
  97         status_t (*destroy) (diffie_hellman_t *this);
  98 };
  99
 100 /**
 101  * Creates a new diffie_hellman_t object
 102  *
 103  * The first diffie hellman public value gets automatically created
 104  *
 105  * @param dh_group_number       Diffie Hellman group number to use
 106  * @return
 107  *                                                      - diffie_hellman_t if successfully
 108  *                                                      - NULL if out of ressources or dh_group not supported
 109  */
 110 diffie_hellman_t *diffie_hellman_create(u_int16_t dh_group_number);
 111
 112 #endif /*DIFFIE_HELLMAN_H_*/