File: esign.h

package info (click to toggle)
libcrypto++ 5.6.4-7
  • links: PTS
  • area: main
  • in suites: stretch
  • size: 11,892 kB
  • ctags: 13,256
  • sloc: cpp: 69,231; sh: 4,117; asm: 4,090; makefile: 363
file content (133 lines) | stat: -rw-r--r-- 4,277 bytes parent folder | download | duplicates (3)
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
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
#ifndef CRYPTOPP_ESIGN_H
#define CRYPTOPP_ESIGN_H

/** \file
	This file contains classes that implement the
	ESIGN signature schemes as defined in IEEE P1363a.
*/

#include "cryptlib.h"
#include "pubkey.h"
#include "integer.h"
#include "asn.h"
#include "misc.h"

NAMESPACE_BEGIN(CryptoPP)

//! _
class ESIGNFunction : public TrapdoorFunction, public ASN1CryptoMaterial<PublicKey>
{
	typedef ESIGNFunction ThisClass;

public:
	void Initialize(const Integer &n, const Integer &e)
		{m_n = n; m_e = e;}

	// PublicKey
	void BERDecode(BufferedTransformation &bt);
	void DEREncode(BufferedTransformation &bt) const;

	// CryptoMaterial
	bool Validate(RandomNumberGenerator &rng, unsigned int level) const;
	bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;
	void AssignFrom(const NameValuePairs &source);

	// TrapdoorFunction
	Integer ApplyFunction(const Integer &x) const;
	Integer PreimageBound() const {return m_n;}
	Integer ImageBound() const {return Integer::Power2(GetK());}

	// non-derived
	const Integer & GetModulus() const {return m_n;}
	const Integer & GetPublicExponent() const {return m_e;}

	void SetModulus(const Integer &n) {m_n = n;}
	void SetPublicExponent(const Integer &e) {m_e = e;}

protected:
	// Covertiy finding on overflow. The library allows small values for research purposes.
	unsigned int GetK() const {return SaturatingSubtract(m_n.BitCount()/3, 1U);}

	Integer m_n, m_e;
};

//! _
class InvertibleESIGNFunction : public ESIGNFunction, public RandomizedTrapdoorFunctionInverse, public PrivateKey
{
	typedef InvertibleESIGNFunction ThisClass;

public:
	void Initialize(const Integer &n, const Integer &e, const Integer &p, const Integer &q)
		{m_n = n; m_e = e; m_p = p; m_q = q;}
	// generate a random private key
	void Initialize(RandomNumberGenerator &rng, unsigned int modulusBits)
		{GenerateRandomWithKeySize(rng, modulusBits);}

	void BERDecode(BufferedTransformation &bt);
	void DEREncode(BufferedTransformation &bt) const;

	Integer CalculateRandomizedInverse(RandomNumberGenerator &rng, const Integer &x) const;

	// GeneratibleCryptoMaterial
	bool Validate(RandomNumberGenerator &rng, unsigned int level) const;
	bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;
	void AssignFrom(const NameValuePairs &source);
	/*! parameters: (ModulusSize) */
	void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg);

	const Integer& GetPrime1() const {return m_p;}
	const Integer& GetPrime2() const {return m_q;}

	void SetPrime1(const Integer &p) {m_p = p;}
	void SetPrime2(const Integer &q) {m_q = q;}

protected:
	Integer m_p, m_q;
};

//! _
template <class T>
class EMSA5Pad : public PK_DeterministicSignatureMessageEncodingMethod
{
public:
	CRYPTOPP_CONSTEXPR static const char *StaticAlgorithmName() {return "EMSA5";}

	void ComputeMessageRepresentative(RandomNumberGenerator &rng,
		const byte *recoverableMessage, size_t recoverableMessageLength,
		HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
		byte *representative, size_t representativeBitLength) const
	{
		CRYPTOPP_UNUSED(rng), CRYPTOPP_UNUSED(recoverableMessage), CRYPTOPP_UNUSED(recoverableMessageLength);
		CRYPTOPP_UNUSED(messageEmpty), CRYPTOPP_UNUSED(hashIdentifier);
		SecByteBlock digest(hash.DigestSize());
		hash.Final(digest);
		size_t representativeByteLength = BitsToBytes(representativeBitLength);
		T mgf;
		mgf.GenerateAndMask(hash, representative, representativeByteLength, digest, digest.size(), false);
		if (representativeBitLength % 8 != 0)
			representative[0] = (byte)Crop(representative[0], representativeBitLength % 8);
	}
};

//! EMSA5, for use with ESIGN
struct P1363_EMSA5 : public SignatureStandard
{
	typedef EMSA5Pad<P1363_MGF1> SignatureMessageEncodingMethod;
};

struct ESIGN_Keys
{
	static std::string StaticAlgorithmName() {return "ESIGN";}
	typedef ESIGNFunction PublicKey;
	typedef InvertibleESIGNFunction PrivateKey;
};

//! ESIGN, as defined in IEEE P1363a
template <class H, class STANDARD = P1363_EMSA5>
struct ESIGN : public TF_SS<STANDARD, H, ESIGN_Keys>
{
};

NAMESPACE_END

#endif