libextra/opencdk/sym-cipher.c

   1 /* -*- Mode: C; c-file-style: "bsd" -*-
   2  * sym-cipher.c
   3  *        Copyright (C) 2003 Timo Schulz
   4  *
   5  * This file is part of OpenCDK.
   6  *
   7  * OpenCDK is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * OpenCDK is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with OpenCDK; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22
  23 #include <stdio.h>
  24 #include <string.h>
  25 #include "opencdk.h"
  26 #include "main.h"
  27 #include "cipher.h"
  28
  29
  30 struct cdk_cipher_hd_s {
  31     gcry_cipher_hd_t hd;
  32     int algo;
  33 };
  34
  35 inline
  36 static int cdk_cipher_to_gcry( int algo)
  37 {
  38     switch( algo ) {
  39     case CDK_CIPHER_BLOWFISH: return GCRY_CIPHER_BLOWFISH;
  40     case CDK_CIPHER_TWOFISH:  return GCRY_CIPHER_TWOFISH;
  41     case CDK_CIPHER_3DES:     return GCRY_CIPHER_3DES;
  42     case CDK_CIPHER_CAST5:    return GCRY_CIPHER_CAST5;
  43     case CDK_CIPHER_AES:      return GCRY_CIPHER_AES;
  44     case CDK_CIPHER_AES192:   return GCRY_CIPHER_AES192;
  45     case CDK_CIPHER_AES256:   return GCRY_CIPHER_AES256;
  46     default: return -1;
  47     }
  48 }
  49
  50 cdk_cipher_hd_t
  51 cdk_cipher_new( int algo, int pgp_sync )
  52 {
  53     cdk_cipher_hd_t hd;
  54     unsigned int flags = 0;
  55     gcry_error_t err;
  56
  57     if( cdk_cipher_test_algo( algo ) )
  58         return NULL;
  59     hd = cdk_calloc( 1, sizeof * hd );
  60     if( !hd )
  61         return NULL;
  62
  63     if( pgp_sync )
  64         flags = GCRY_CIPHER_ENABLE_SYNC;
  65
  66     hd->algo = algo;
  67
  68     err = gcry_cipher_open( &hd->hd, cdk_cipher_to_gcry(algo),
  69         GCRY_CIPHER_MODE_CFB, flags);
  70     if( err ) {
  71         cdk_free( hd );
  72         return NULL;
  73     }
  74     return hd;
  75 }
  76
  77
  78 cdk_cipher_hd_t
  79 cdk_cipher_open( int algo, int pgp_sync,
  80                  const byte * key, size_t keylen,
  81                  const byte * ivbuf, size_t ivlen )
  82 {
  83     cdk_cipher_hd_t hd;
  84     gcry_error_t err;
  85
  86     hd = cdk_cipher_new( algo, pgp_sync );
  87     if( hd ) {
  88         err = gcry_cipher_setkey( hd->hd, key, keylen );
  89         if( !err)
  90             err = gcry_cipher_setiv( hd->hd, ivbuf, ivlen );
  91         if( err) {
  92             cdk_cipher_close( hd );
  93             hd = NULL;
  94         }
  95     }
  96     return hd;
  97 }
  98
  99
 100 void
 101 cdk_cipher_close( cdk_cipher_hd_t hd )
 102 {
 103     if( !hd )
 104         return;
 105     gcry_cipher_close( hd->hd);
 106     cdk_free( hd );
 107 }
 108
 109
 110 int
 111 cdk_cipher_decrypt( cdk_cipher_hd_t hd, byte * outbuf, const byte *inbuf,
 112                     size_t nbytes )
 113 {
 114 gcry_error_t err;
 115
 116     if( !hd )
 117         return CDK_Inv_Value;
 118     err = gcry_cipher_decrypt( hd->hd, outbuf, nbytes, inbuf, nbytes);
 119
 120     if (err) return CDK_Gcry_Error;
 121     else return 0;
 122 }
 123
 124
 125 int
 126 cdk_cipher_encrypt( cdk_cipher_hd_t hd, byte * outbuf, const byte *inbuf,
 127                     size_t nbytes )
 128 {
 129 gcry_error_t err;
 130
 131     if( !hd )
 132         return CDK_Inv_Value;
 133     err = gcry_cipher_encrypt( hd->hd, outbuf, nbytes, inbuf, nbytes);
 134
 135     if (err) return CDK_Gcry_Error;
 136     else return 0;
 137 }
 138
 139
 140 void
 141 cdk_cipher_sync( cdk_cipher_hd_t hd )
 142 {
 143     gcry_cipher_sync( hd->hd);
 144 }
 145
 146
 147 int
 148 cdk_cipher_setiv( cdk_cipher_hd_t hd, const byte *ivbuf, size_t ivlen )
 149 {
 150     if( !hd )
 151         return CDK_Inv_Value;
 152
 153     gcry_cipher_setiv( hd->hd, ivbuf, ivlen);
 154     return 0;
 155 }
 156
 157
 158 int
 159 cdk_cipher_setkey( cdk_cipher_hd_t hd, const byte *keybuf, size_t keylen )
 160 {
 161     if( !hd )
 162         return CDK_Inv_Value;
 163
 164     gcry_cipher_setkey( hd->hd, keybuf, keylen);
 165     return 0;
 166 }
 167
 168
 169 int
 170 cdk_cipher_get_algo_blklen( int algo )
 171 {
 172     return gcry_cipher_get_algo_blklen( cdk_cipher_to_gcry( algo));
 173 }
 174
 175
 176 int
 177 cdk_cipher_get_algo_keylen( int algo )
 178 {
 179     return gcry_cipher_get_algo_keylen( cdk_cipher_to_gcry( algo));
 180 }
 181
 182
 183 int
 184 cdk_cipher_test_algo( int algo )
 185 {
 186     return gcry_cipher_test_algo( cdk_cipher_to_gcry( algo));
 187 }