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
|
#ifndef CRYPTOPP_TRUNHASH_H
#define CRYPTOPP_TRUNHASH_H
#include "cryptlib.h"
NAMESPACE_BEGIN(CryptoPP)
class NullHash : public HashTransformation
{
public:
void Update(const byte *input, size_t length) {}
unsigned int DigestSize() const {return 0;}
void TruncatedFinal(byte *digest, size_t digestSize) {}
bool TruncatedVerify(const byte *digest, size_t digestLength) {return true;}
};
//! construct new HashModule with smaller DigestSize() from existing one
template <class T>
class TruncatedHashTemplate : public HashTransformation
{
public:
TruncatedHashTemplate(T hm, unsigned int digestSize)
: m_hm(hm), m_digestSize(digestSize) {}
TruncatedHashTemplate(const byte *key, size_t keyLength, unsigned int digestSize)
: m_hm(key, keyLength), m_digestSize(digestSize) {}
TruncatedHashTemplate(size_t digestSize)
: m_digestSize(digestSize) {}
void Restart()
{m_hm.Restart();}
void Update(const byte *input, size_t length)
{m_hm.Update(input, length);}
unsigned int DigestSize() const {return m_digestSize;}
void TruncatedFinal(byte *digest, size_t digestSize)
{m_hm.TruncatedFinal(digest, digestSize);}
bool TruncatedVerify(const byte *digest, size_t digestLength)
{return m_hm.TruncatedVerify(digest, digestLength);}
private:
T m_hm;
unsigned int m_digestSize;
};
typedef TruncatedHashTemplate<HashTransformation &> TruncatedHashModule;
NAMESPACE_END
#endif
|
