src/libstrongswan/crypto/diffie_hellman.h

   1 /*
   2  * Copyright (C) 2005-2007 Martin Willi
   3  * Copyright (C) 2005 Jan Hutter
   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  * $Id$
  17  */
  18
  19 /**
  20  * @defgroup diffie_hellman diffie_hellman
  21  * @{ @ingroup crypto
  22  */
  23
  24 #ifndef DIFFIE_HELLMAN_H_
  25 #define DIFFIE_HELLMAN_H_
  26
  27 typedef enum diffie_hellman_group_t diffie_hellman_group_t;
  28 typedef struct diffie_hellman_t diffie_hellman_t;
  29
  30 #include <library.h>
  31
  32 /**
  33  * Diffie-Hellman group.
  34  *
  35  * The modulus (or group) to use for a Diffie-Hellman calculation.
  36  * See IKEv2 RFC 3.3.2 and RFC 3526.
  37  *
  38  * ECP groups are defined in RFC 4753.
  39  */
  40 enum diffie_hellman_group_t {
  41         MODP_NONE = 0,
  42         MODP_768_BIT = 1,
  43         MODP_1024_BIT = 2,
  44         MODP_1536_BIT = 5,
  45         MODP_2048_BIT = 14,
  46         MODP_3072_BIT = 15,
  47         MODP_4096_BIT = 16,
  48         MODP_6144_BIT = 17,
  49         MODP_8192_BIT = 18,
  50         ECP_256_BIT = 19,
  51         ECP_384_BIT = 20,
  52         ECP_521_BIT = 21,
  53
  54 };
  55
  56 /**
  57  * enum name for diffie_hellman_group_t.
  58  */
  59 extern enum_name_t *diffie_hellman_group_names;
  60
  61 /**
  62  * Implementation of the Diffie-Hellman algorithm, as in RFC2631.
  63  */
  64 struct diffie_hellman_t {
  65
  66         /**
  67          * Returns the shared secret of this diffie hellman exchange.
  68          *
  69          * Space for returned secret is allocated and must be
  70          * freed by the caller.
  71          *
  72          * @param secret        shared secret will be written into this chunk
  73          * @return                      SUCCESS, FAILED if not both DH values are set
  74          */
  75         status_t (*get_shared_secret) (diffie_hellman_t *this, chunk_t *secret);
  76
  77         /**
  78          * Sets the public value of partner.
  79          *
  80          * Chunk gets cloned and can be destroyed afterwards.
  81          *
  82          * @param value         public value of partner
  83          */
  84         void (*set_other_public_value) (diffie_hellman_t *this, chunk_t value);
  85
  86         /**
  87          * Gets the public value of partner.
  88          *
  89          * Space for returned chunk is allocated and must be freed by the caller.
  90          *
  91          * @param value         public value of partner is stored at this location
  92          * @return                      SUCCESS, FAILED if other public value not set
  93          */
  94         status_t (*get_other_public_value) (diffie_hellman_t *this, chunk_t *value);
  95
  96         /**
  97          * Gets the own public value to transmit.
  98          *
  99          * Space for returned chunk is allocated and must be freed by the caller.
 100          *
 101          * @param value         public value of caller is stored at this location
 102          */
 103         void (*get_my_public_value) (diffie_hellman_t *this, chunk_t *value);
 104
 105         /**
 106          * Get the DH group used.
 107          *
 108          * @return                      DH group set in construction
 109          */
 110         diffie_hellman_group_t (*get_dh_group) (diffie_hellman_t *this);
 111
 112         /**
 113          * Destroys an diffie_hellman_t object.
 114          */
 115         void (*destroy) (diffie_hellman_t *this);
 116 };
 117
 118 #endif /*DIFFIE_HELLMAN_H_ @} */