src/libcharon/sa/keymat.c

   1 /*
   2  * Copyright (C) 2011 Tobias Brunner
   3  * Hochschule fuer Technik Rapperswil
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation; either version 2 of the License, or (at your
   8  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * for more details.
  14  */
  15
  16 #include "keymat.h"
  17
  18 #include <sa/ikev1/keymat_v1.h>
  19 #include <sa/ikev2/keymat_v2.h>
  20
  21 /**
  22  * See header
  23  */
  24 keymat_t *keymat_create(ike_version_t version, bool initiator)
  25 {
  26         switch (version)
  27         {
  28                 case IKEV1:
  29 #ifdef USE_IKEV1
  30                         return &keymat_v1_create(initiator)->keymat;
  31 #endif
  32                         break;
  33                 case IKEV2:
  34 #ifdef USE_IKEV2
  35                         return &keymat_v2_create(initiator)->keymat;
  36 #endif
  37                         break;
  38                 default:
  39                         break;
  40         }
  41         return NULL;
  42 }
  43
  44 /**
  45  * Implicit key length for an algorithm
  46  */
  47 typedef struct {
  48         /** IKEv2 algorithm identifier */
  49         int alg;
  50         /** key length in bits */
  51         int len;
  52 } keylen_entry_t;
  53
  54 /**
  55  * See header.
  56  */
  57 int keymat_get_keylen_encr(encryption_algorithm_t alg)
  58 {
  59         keylen_entry_t map[] = {
  60                 {ENCR_DES,                                       64},
  61                 {ENCR_3DES,                                     192},
  62         };
  63         int i;
  64
  65         for (i = 0; i < countof(map); i++)
  66         {
  67                 if (map[i].alg == alg)
  68                 {
  69                         return map[i].len;
  70                 }
  71         }
  72         return 0;
  73 }
  74
  75 /**
  76  * See header.
  77  */
  78 int keymat_get_keylen_integ(integrity_algorithm_t alg)
  79 {
  80         keylen_entry_t map[] = {
  81                 {AUTH_HMAC_MD5_96,                      128},
  82                 {AUTH_HMAC_SHA1_96,                     160},
  83                 {AUTH_HMAC_SHA2_256_96,         256},
  84                 {AUTH_HMAC_SHA2_256_128,        256},
  85                 {AUTH_HMAC_SHA2_384_192,        384},
  86                 {AUTH_HMAC_SHA2_512_256,        512},
  87                 {AUTH_AES_XCBC_96,                      128},
  88         };
  89         int i;
  90
  91         for (i = 0; i < countof(map); i++)
  92         {
  93                 if (map[i].alg == alg)
  94                 {
  95                         return map[i].len;
  96                 }
  97         }
  98         return 0;
  99 }