CRYPTOPP 5.6.3 RC6 checkin

1 files changed, 294 insertions, 295 deletions

diff --git a/ec2n.cpp b/ec2n.cpp
index 01c7e3fc..596cf874 100644
--- a/ec2n.cpp
+++ b/ec2n.cpp
@@ -1,295 +1,294 @@
-// ec2n.cpp - written and placed in the public domain by Wei Dai
-
-#include "pch.h"
-
-#ifndef CRYPTOPP_IMPORTS
-
-#include "ec2n.h"
-#include "asn.h"
-
-#include "algebra.cpp"
-#include "eprecomp.cpp"
-#include "trap.h"
-
-NAMESPACE_BEGIN(CryptoPP)
-
-EC2N::EC2N(BufferedTransformation &bt)
-	: m_field(BERDecodeGF2NP(bt))
-{
-	BERSequenceDecoder seq(bt);
-	m_field->BERDecodeElement(seq, m_a);
-	m_field->BERDecodeElement(seq, m_b);
-	// skip optional seed
-	if (!seq.EndReached())
-	{
-		SecByteBlock seed;
-		unsigned int unused;
-		BERDecodeBitString(seq, seed, unused);
-	}
-	seq.MessageEnd();
-}
-
-void EC2N::DEREncode(BufferedTransformation &bt) const
-{
-	m_field->DEREncode(bt);
-	DERSequenceEncoder seq(bt);
-	m_field->DEREncodeElement(seq, m_a);
-	m_field->DEREncodeElement(seq, m_b);
-	seq.MessageEnd();
-}
-
-bool EC2N::DecodePoint(EC2N::Point &P, const byte *encodedPoint, size_t encodedPointLen) const
-{
-	StringStore store(encodedPoint, encodedPointLen);
-	return DecodePoint(P, store, encodedPointLen);
-}
-
-bool EC2N::DecodePoint(EC2N::Point &P, BufferedTransformation &bt, size_t encodedPointLen) const
-{
-	byte type;
-	if (encodedPointLen < 1 || !bt.Get(type))
-		return false;
-
-	switch (type)
-	{
-	case 0:
-		P.identity = true;
-		return true;
-	case 2:
-	case 3:
-	{
-		if (encodedPointLen != EncodedPointSize(true))
-			return false;
-
-		P.identity = false;
-		P.x.Decode(bt, m_field->MaxElementByteLength()); 
-
-		if (P.x.IsZero())
-		{
-			P.y = m_field->SquareRoot(m_b);
-			return true;
-		}
-
-		FieldElement z = m_field->Square(P.x);
-		CRYPTOPP_ASSERT(P.x == m_field->SquareRoot(z));
-		P.y = m_field->Divide(m_field->Add(m_field->Multiply(z, m_field->Add(P.x, m_a)), m_b), z);
-		CRYPTOPP_ASSERT(P.x == m_field->Subtract(m_field->Divide(m_field->Subtract(m_field->Multiply(P.y, z), m_b), z), m_a));
-		z = m_field->SolveQuadraticEquation(P.y);
-		CRYPTOPP_ASSERT(m_field->Add(m_field->Square(z), z) == P.y);
-		z.SetCoefficient(0, type & 1);
-
-		P.y = m_field->Multiply(z, P.x);
-		return true;
-	}
-	case 4:
-	{
-		if (encodedPointLen != EncodedPointSize(false))
-			return false;
-
-		unsigned int len = m_field->MaxElementByteLength();
-		P.identity = false;
-		P.x.Decode(bt, len);
-		P.y.Decode(bt, len);
-		return true;
-	}
-	default:
-		return false;
-	}
-}
-
-void EC2N::EncodePoint(BufferedTransformation &bt, const Point &P, bool compressed) const
-{
-	if (P.identity)
-		NullStore().TransferTo(bt, EncodedPointSize(compressed));
-	else if (compressed)
-	{
-		bt.Put(2 + (!P.x ? 0 : m_field->Divide(P.y, P.x).GetBit(0)));
-		P.x.Encode(bt, m_field->MaxElementByteLength());
-	}
-	else
-	{
-		unsigned int len = m_field->MaxElementByteLength();
-		bt.Put(4);	// uncompressed
-		P.x.Encode(bt, len);
-		P.y.Encode(bt, len);
-	}
-}
-
-void EC2N::EncodePoint(byte *encodedPoint, const Point &P, bool compressed) const
-{
-	ArraySink sink(encodedPoint, EncodedPointSize(compressed));
-	EncodePoint(sink, P, compressed);
-	CRYPTOPP_ASSERT(sink.TotalPutLength() == EncodedPointSize(compressed));
-}
-
-EC2N::Point EC2N::BERDecodePoint(BufferedTransformation &bt) const
-{
-	SecByteBlock str;
-	BERDecodeOctetString(bt, str);
-	Point P;
-	if (!DecodePoint(P, str, str.size()))
-		BERDecodeError();
-	return P;
-}
-
-void EC2N::DEREncodePoint(BufferedTransformation &bt, const Point &P, bool compressed) const
-{
-	SecByteBlock str(EncodedPointSize(compressed));
-	EncodePoint(str, P, compressed);
-	DEREncodeOctetString(bt, str);
-}
-
-bool EC2N::ValidateParameters(RandomNumberGenerator &rng, unsigned int level) const
-{
-	bool pass = !!m_b;
-	pass = pass && m_a.CoefficientCount() <= m_field->MaxElementBitLength();
-	pass = pass && m_b.CoefficientCount() <= m_field->MaxElementBitLength();
-
-	if (level >= 1)
-		pass = pass && m_field->GetModulus().IsIrreducible();
-		
-	return pass;
-}
-
-bool EC2N::VerifyPoint(const Point &P) const
-{
-	const FieldElement &x = P.x, &y = P.y;
-	return P.identity || 
-		(x.CoefficientCount() <= m_field->MaxElementBitLength()
-		&& y.CoefficientCount() <= m_field->MaxElementBitLength()
-		&& !(((x+m_a)*x*x+m_b-(x+y)*y)%m_field->GetModulus()));
-}
-
-bool EC2N::Equal(const Point &P, const Point &Q) const
-{
-	if (P.identity && Q.identity)
-		return true;
-
-	if (P.identity && !Q.identity)
-		return false;
-
-	if (!P.identity && Q.identity)
-		return false;
-
-	return (m_field->Equal(P.x,Q.x) && m_field->Equal(P.y,Q.y));
-}
-
-const EC2N::Point& EC2N::Identity() const
-{
-	return Singleton<Point>().Ref();
-}
-
-const EC2N::Point& EC2N::Inverse(const Point &P) const
-{
-	if (P.identity)
-		return P;
-	else
-	{
-		m_R.identity = false;
-		m_R.y = m_field->Add(P.x, P.y);
-		m_R.x = P.x;
-		return m_R;
-	}
-}
-
-const EC2N::Point& EC2N::Add(const Point &P, const Point &Q) const
-{
-	if (P.identity) return Q;
-	if (Q.identity) return P;
-	if (Equal(P, Q)) return Double(P);
-	if (m_field->Equal(P.x, Q.x) && m_field->Equal(P.y, m_field->Add(Q.x, Q.y))) return Identity();
-
-	FieldElement t = m_field->Add(P.y, Q.y);
-	t = m_field->Divide(t, m_field->Add(P.x, Q.x));
-	FieldElement x = m_field->Square(t);
-	m_field->Accumulate(x, t);
-	m_field->Accumulate(x, Q.x);
-	m_field->Accumulate(x, m_a);
-	m_R.y = m_field->Add(P.y, m_field->Multiply(t, x));
-	m_field->Accumulate(x, P.x);
-	m_field->Accumulate(m_R.y, x);
-
-	m_R.x.swap(x);
-	m_R.identity = false;
-	return m_R;
-}
-
-const EC2N::Point& EC2N::Double(const Point &P) const
-{
-	if (P.identity) return P;
-	if (!m_field->IsUnit(P.x)) return Identity();
-
-	FieldElement t = m_field->Divide(P.y, P.x);
-	m_field->Accumulate(t, P.x);
-	m_R.y = m_field->Square(P.x);
-	m_R.x = m_field->Square(t);
-	m_field->Accumulate(m_R.x, t);
-	m_field->Accumulate(m_R.x, m_a);
-	m_field->Accumulate(m_R.y, m_field->Multiply(t, m_R.x));
-	m_field->Accumulate(m_R.y, m_R.x);
-
-	m_R.identity = false;
-	return m_R;
-}
-
-// ********************************************************
-
-/*
-EcPrecomputation<EC2N>& EcPrecomputation<EC2N>::operator=(const EcPrecomputation<EC2N> &rhs)
-{
-	if (this != &rhs)
-	{
-		DL_GroupPrecomputation::operator=(rhs);
-		m_ec = rhs.m_ec;
-	}
-	return *this;
-}
-
-void EcPrecomputation<EC2N>::SetCurveAndBase(const EC2N &ec, const EC2N::Point &base)
-{
-	m_ec.reset(new EC2N(ec));
-	m_ep.SetGroupAndBase(*m_ec, base);
-}
-
-void EcPrecomputation<EC2N>::Precompute(unsigned int maxExpBits, unsigned int storage)
-{
-	m_ep.Precompute(maxExpBits, storage);
-}
-
-void EcPrecomputation<EC2N>::Load(BufferedTransformation &bt)
-{
-	BERSequenceDecoder seq(bt);
-	word32 version;
-	BERDecodeUnsigned<word32>(seq, version, INTEGER, 1, 1);
-	m_ep.m_exponentBase.BERDecode(seq);
-	m_ep.m_windowSize = m_ep.m_exponentBase.BitCount() - 1;
-	m_ep.m_bases.clear();
-	while (!seq.EndReached())
-		m_ep.m_bases.push_back(m_ec->BERDecodePoint(seq));
-	seq.MessageEnd();
-}
-
-void EcPrecomputation<EC2N>::Save(BufferedTransformation &bt) const
-{
-	DERSequenceEncoder seq(bt);
-	DEREncodeUnsigned<word32>(seq, 1);	// version
-	m_ep.m_exponentBase.DEREncode(seq);
-	for (unsigned i=0; i<m_ep.m_bases.size(); i++)
-		m_ec->DEREncodePoint(seq, m_ep.m_bases[i]);
-	seq.MessageEnd();
-}
-
-EC2N::Point EcPrecomputation<EC2N>::Exponentiate(const Integer &exponent) const
-{
-	return m_ep.Exponentiate(exponent);
-}
-
-EC2N::Point EcPrecomputation<EC2N>::CascadeExponentiate(const Integer &exponent, const DL_FixedBasePrecomputation<Element> &pc2, const Integer &exponent2) const
-{
-	return m_ep.CascadeExponentiate(exponent, static_cast<const EcPrecomputation<EC2N> &>(pc2).m_ep, exponent2);
-}
-*/
-
-NAMESPACE_END
-
-#endif
+// ec2n.cpp - written and placed in the public domain by Wei Dai

+

+#include "pch.h"

+

+#ifndef CRYPTOPP_IMPORTS

+

+#include "ec2n.h"

+#include "asn.h"

+#include "integer.h"

+#include "filters.h"

+#include "algebra.cpp"

+#include "eprecomp.cpp"

+

+NAMESPACE_BEGIN(CryptoPP)

+

+EC2N::EC2N(BufferedTransformation &bt)

+	: m_field(BERDecodeGF2NP(bt))

+{

+	BERSequenceDecoder seq(bt);

+	m_field->BERDecodeElement(seq, m_a);

+	m_field->BERDecodeElement(seq, m_b);

+	// skip optional seed

+	if (!seq.EndReached())

+	{

+		SecByteBlock seed;

+		unsigned int unused;

+		BERDecodeBitString(seq, seed, unused);

+	}

+	seq.MessageEnd();

+}

+

+void EC2N::DEREncode(BufferedTransformation &bt) const

+{

+	m_field->DEREncode(bt);

+	DERSequenceEncoder seq(bt);

+	m_field->DEREncodeElement(seq, m_a);

+	m_field->DEREncodeElement(seq, m_b);

+	seq.MessageEnd();

+}

+

+bool EC2N::DecodePoint(EC2N::Point &P, const byte *encodedPoint, size_t encodedPointLen) const

+{

+	StringStore store(encodedPoint, encodedPointLen);

+	return DecodePoint(P, store, encodedPointLen);

+}

+

+bool EC2N::DecodePoint(EC2N::Point &P, BufferedTransformation &bt, size_t encodedPointLen) const

+{

+	byte type;

+	if (encodedPointLen < 1 || !bt.Get(type))

+		return false;

+

+	switch (type)

+	{

+	case 0:

+		P.identity = true;

+		return true;

+	case 2:

+	case 3:

+	{

+		if (encodedPointLen != EncodedPointSize(true))

+			return false;

+

+		P.identity = false;

+		P.x.Decode(bt, m_field->MaxElementByteLength()); 

+

+		if (P.x.IsZero())

+		{

+			P.y = m_field->SquareRoot(m_b);

+			return true;

+		}

+

+		FieldElement z = m_field->Square(P.x);

+		assert(P.x == m_field->SquareRoot(z));

+		P.y = m_field->Divide(m_field->Add(m_field->Multiply(z, m_field->Add(P.x, m_a)), m_b), z);

+		assert(P.x == m_field->Subtract(m_field->Divide(m_field->Subtract(m_field->Multiply(P.y, z), m_b), z), m_a));

+		z = m_field->SolveQuadraticEquation(P.y);

+		assert(m_field->Add(m_field->Square(z), z) == P.y);

+		z.SetCoefficient(0, type & 1);

+

+		P.y = m_field->Multiply(z, P.x);

+		return true;

+	}

+	case 4:

+	{

+		if (encodedPointLen != EncodedPointSize(false))

+			return false;

+

+		unsigned int len = m_field->MaxElementByteLength();

+		P.identity = false;

+		P.x.Decode(bt, len);

+		P.y.Decode(bt, len);

+		return true;

+	}

+	default:

+		return false;

+	}

+}

+

+void EC2N::EncodePoint(BufferedTransformation &bt, const Point &P, bool compressed) const

+{

+	if (P.identity)

+		NullStore().TransferTo(bt, EncodedPointSize(compressed));

+	else if (compressed)

+	{

+		bt.Put(2 + (!P.x ? 0 : m_field->Divide(P.y, P.x).GetBit(0)));

+		P.x.Encode(bt, m_field->MaxElementByteLength());

+	}

+	else

+	{

+		unsigned int len = m_field->MaxElementByteLength();

+		bt.Put(4);	// uncompressed

+		P.x.Encode(bt, len);

+		P.y.Encode(bt, len);

+	}

+}

+

+void EC2N::EncodePoint(byte *encodedPoint, const Point &P, bool compressed) const

+{

+	ArraySink sink(encodedPoint, EncodedPointSize(compressed));

+	EncodePoint(sink, P, compressed);

+	assert(sink.TotalPutLength() == EncodedPointSize(compressed));

+}

+

+EC2N::Point EC2N::BERDecodePoint(BufferedTransformation &bt) const

+{

+	SecByteBlock str;

+	BERDecodeOctetString(bt, str);

+	Point P;

+	if (!DecodePoint(P, str, str.size()))

+		BERDecodeError();

+	return P;

+}

+

+void EC2N::DEREncodePoint(BufferedTransformation &bt, const Point &P, bool compressed) const

+{

+	SecByteBlock str(EncodedPointSize(compressed));

+	EncodePoint(str, P, compressed);

+	DEREncodeOctetString(bt, str);

+}

+

+bool EC2N::ValidateParameters(RandomNumberGenerator &rng, unsigned int level) const

+{

+	CRYPTOPP_UNUSED(rng);

+	bool pass = !!m_b;

+	pass = pass && m_a.CoefficientCount() <= m_field->MaxElementBitLength();

+	pass = pass && m_b.CoefficientCount() <= m_field->MaxElementBitLength();

+

+	if (level >= 1)

+		pass = pass && m_field->GetModulus().IsIrreducible();

+		

+	return pass;

+}

+

+bool EC2N::VerifyPoint(const Point &P) const

+{

+	const FieldElement &x = P.x, &y = P.y;

+	return P.identity || 

+		(x.CoefficientCount() <= m_field->MaxElementBitLength()

+		&& y.CoefficientCount() <= m_field->MaxElementBitLength()

+		&& !(((x+m_a)*x*x+m_b-(x+y)*y)%m_field->GetModulus()));

+}

+

+bool EC2N::Equal(const Point &P, const Point &Q) const

+{

+	if (P.identity && Q.identity)

+		return true;

+

+	if (P.identity && !Q.identity)

+		return false;

+

+	if (!P.identity && Q.identity)

+		return false;

+

+	return (m_field->Equal(P.x,Q.x) && m_field->Equal(P.y,Q.y));

+}

+

+const EC2N::Point& EC2N::Identity() const

+{

+	return Singleton<Point>().Ref();

+}

+

+const EC2N::Point& EC2N::Inverse(const Point &P) const

+{

+	if (P.identity)

+		return P;

+	else

+	{

+		m_R.identity = false;

+		m_R.y = m_field->Add(P.x, P.y);

+		m_R.x = P.x;

+		return m_R;

+	}

+}

+

+const EC2N::Point& EC2N::Add(const Point &P, const Point &Q) const

+{

+	if (P.identity) return Q;

+	if (Q.identity) return P;

+	if (Equal(P, Q)) return Double(P);

+	if (m_field->Equal(P.x, Q.x) && m_field->Equal(P.y, m_field->Add(Q.x, Q.y))) return Identity();

+

+	FieldElement t = m_field->Add(P.y, Q.y);

+	t = m_field->Divide(t, m_field->Add(P.x, Q.x));

+	FieldElement x = m_field->Square(t);

+	m_field->Accumulate(x, t);

+	m_field->Accumulate(x, Q.x);

+	m_field->Accumulate(x, m_a);

+	m_R.y = m_field->Add(P.y, m_field->Multiply(t, x));

+	m_field->Accumulate(x, P.x);

+	m_field->Accumulate(m_R.y, x);

+

+	m_R.x.swap(x);

+	m_R.identity = false;

+	return m_R;

+}

+

+const EC2N::Point& EC2N::Double(const Point &P) const

+{

+	if (P.identity) return P;

+	if (!m_field->IsUnit(P.x)) return Identity();

+

+	FieldElement t = m_field->Divide(P.y, P.x);

+	m_field->Accumulate(t, P.x);

+	m_R.y = m_field->Square(P.x);

+	m_R.x = m_field->Square(t);

+	m_field->Accumulate(m_R.x, t);

+	m_field->Accumulate(m_R.x, m_a);

+	m_field->Accumulate(m_R.y, m_field->Multiply(t, m_R.x));

+	m_field->Accumulate(m_R.y, m_R.x);

+

+	m_R.identity = false;

+	return m_R;

+}

+

+// ********************************************************

+

+/*

+EcPrecomputation<EC2N>& EcPrecomputation<EC2N>::operator=(const EcPrecomputation<EC2N> &rhs)

+{

+	m_ec = rhs.m_ec;

+	m_ep = rhs.m_ep;

+	m_ep.m_group = m_ec.get();

+	return *this;

+}

+

+void EcPrecomputation<EC2N>::SetCurveAndBase(const EC2N &ec, const EC2N::Point &base)

+{

+	m_ec.reset(new EC2N(ec));

+	m_ep.SetGroupAndBase(*m_ec, base);

+}

+

+void EcPrecomputation<EC2N>::Precompute(unsigned int maxExpBits, unsigned int storage)

+{

+	m_ep.Precompute(maxExpBits, storage);

+}

+

+void EcPrecomputation<EC2N>::Load(BufferedTransformation &bt)

+{

+	BERSequenceDecoder seq(bt);

+	word32 version;

+	BERDecodeUnsigned<word32>(seq, version, INTEGER, 1, 1);

+	m_ep.m_exponentBase.BERDecode(seq);

+	m_ep.m_windowSize = m_ep.m_exponentBase.BitCount() - 1;

+	m_ep.m_bases.clear();

+	while (!seq.EndReached())

+		m_ep.m_bases.push_back(m_ec->BERDecodePoint(seq));

+	seq.MessageEnd();

+}

+

+void EcPrecomputation<EC2N>::Save(BufferedTransformation &bt) const

+{

+	DERSequenceEncoder seq(bt);

+	DEREncodeUnsigned<word32>(seq, 1);	// version

+	m_ep.m_exponentBase.DEREncode(seq);

+	for (unsigned i=0; i<m_ep.m_bases.size(); i++)

+		m_ec->DEREncodePoint(seq, m_ep.m_bases[i]);

+	seq.MessageEnd();

+}

+

+EC2N::Point EcPrecomputation<EC2N>::Exponentiate(const Integer &exponent) const

+{

+	return m_ep.Exponentiate(exponent);

+}

+

+EC2N::Point EcPrecomputation<EC2N>::CascadeExponentiate(const Integer &exponent, const DL_FixedBasePrecomputation<Element> &pc2, const Integer &exponent2) const

+{

+	return m_ep.CascadeExponentiate(exponent, static_cast<const EcPrecomputation<EC2N> &>(pc2).m_ep, exponent2);

+}

+*/

+

+NAMESPACE_END

+

+#endif