1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
|
/*
* rsyncrypto - an rsync friendly encryption
* Copyright (C) 2006-2008 Shachar Shemesh for Lingnu Open Source Consulting ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* In addition, as a special exception, the rsyncrypto authors give permission
* to link the code of this program with the OpenSSL library (or with modified
* versions of OpenSSL that use the same license as OpenSSL), and distribute
* linked combinations including the two. You must obey the GNU General Public
* License in all respects for all of the code used other than OpenSSL. If you
* modify this file, you may extend this exception to your version of the file,
* but you are not obligated to do so. If you do not wish to do so, delete this
* exception statement from your version.
*
* The project's homepage is at http://rsyncrypto.lingnu.com/
*/
#include <precomp.h>
#include "aes_crypt.h"
aes_key::aes_key( uint16_t key_size, uint32_t sum_span, uint32_t sum_mod, uint32_t sum_min_dist,
const unsigned char *buffer ) : key(key_size, CYPHER_AES, sum_span, sum_mod, sum_min_dist),
secret_key(new unsigned char[key_size])
{
const aes_export *import=reinterpret_cast<const aes_export *>(buffer);
memcpy( aes_header.iv, import->iv, sizeof(aes_header.iv) );
memcpy( secret_key.get(), import->key, key_size );
update_keys();
}
aes_key::aes_key( size_t keybits, uint32_t sum_span, uint32_t sum_mod, uint32_t sum_min_dist ) :
key(keybits==0?32:(keybits+7)/8, CYPHER_AES, sum_span, sum_mod, sum_min_dist ),
secret_key(new unsigned char[header.key_size])
{
if( !RAND_bytes(aes_header.iv, sizeof( aes_header.iv )) ||
!RAND_bytes(secret_key.get(), header.key_size) )
throw rscerror("No random entropy for key and IV");
update_keys();
}
aes_key::aes_key( const aes_key &that ) : key( that.header.key_size, CYPHER_AES, that.header.sum_span,
that.header.sum_mod, that.header.sum_min_dist ), secret_key( new unsigned char [header.key_size] )
{
memcpy( aes_header.iv, that.aes_header.iv, sizeof( aes_header.iv ) );
memcpy( secret_key.get(), that.secret_key.get(), header.key_size );
update_keys();
}
size_t aes_key::export_key( void *buffer ) const
{
unsigned char *buff=static_cast<unsigned char *>(buffer);
size_t length=key::export_key( buffer );
memcpy( buff+length, aes_header.iv, sizeof( aes_header.iv ) );
length+=sizeof( aes_header.iv );
memcpy( buff+length, secret_key.get(), header.key_size );
length+=header.key_size;
return length;
}
key *aes_key::gen_pad_key() const
{
std::unique_ptr<aes_key> ret(new aes_key(*this));
for( unsigned int i=0; i<sizeof(aes_header.iv); ++i )
ret->aes_header.iv[i]=~ret->aes_header.iv[i];
return ret.release();
}
void aes_key::init_encrypt()
{
key::init_encrypt();
memcpy( cbc_base, aes_header.iv, sizeof(cbc_base) );
}
void aes_key::encrypt_block( unsigned char *data, size_t size )
{
AES_cbc_encrypt( data, data, size, &encrypt_key, cbc_base, AES_ENCRYPT );
}
void aes_key::decrypt_block( unsigned char *data, size_t size )
{
AES_cbc_encrypt( data, data, size, &decrypt_key, cbc_base, AES_DECRYPT );
}
|
