1 files changed, 128 insertions, 0 deletions
diff --git a/CryptoPP/esign.h b/CryptoPP/esign.h
new file mode 100644
index 000000000..8eecbc5a1
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+++ b/CryptoPP/esign.h
@@ -0,0 +1,128 @@
+#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 "pubkey.h"
+#include "integer.h"
+#include "asn.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:
+	unsigned int GetK() const {return m_n.BitCount()/3-1;}
+
+	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:
+	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
+	{
+		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