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
|
#ifndef BU_MODE_OFB_H
#define BU_MODE_OFB_H
#include "bu/filter.h"
#include "bu/string.h"
namespace Bu
{
template<int iBlockSize, typename CipherType>
class CipherModeOfb : public CipherType
{
public:
CipherModeOfb(class Stream &rNext ) :
CipherType( rNext ),
bStart( true )
{
memset( aVector, 0, iBlockSize );
}
virtual ~CipherModeOfb()
{
}
void setIv( const Bu::String &sIv )
{
memcpy( aVector, sIv.getStr(), iBlockSize );
}
protected:
void decipher( void *pBuf )
{
CipherType::encipher( aVector );
uint8_t aTmp[iBlockSize];
memcpy( aTmp, aVector, iBlockSize );
for( int j = 0; j < iBlockSize; j++ )
((uint8_t *)pBuf)[j] ^= aVector[j];
memcpy( aVector, aTmp, iBlockSize );
}
void encipher( void *pBuf )
{
CipherType::encipher( aVector );
uint8_t aTmp[iBlockSize];
memcpy( aTmp, aVector, iBlockSize );
for( int j = 0; j < iBlockSize; j++ )
((uint8_t *)pBuf)[j] ^= aVector[j];
memcpy( aVector, aTmp, iBlockSize );
}
private:
bool bStart;
uint8_t aVector[iBlockSize];
};
};
#endif
|
