Initial revision

git-svn-id: svn://svn.code.sf.net/p/cryptopp/code/trunk/c5@2 57ff6487-cd31-0410-9ec3-f628ee90f5f0

1 files changed, 214 insertions, 0 deletions

diff --git a/rabin.cpp b/rabin.cpp
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+// rabin.cpp - written and placed in the public domain by Wei Dai
+
+#include "pch.h"
+#include "rabin.h"
+#include "nbtheory.h"
+#include "asn.h"
+#include "sha.h"
+
+#include "oaep.cpp"
+
+NAMESPACE_BEGIN(CryptoPP)
+
+void RabinFunction::BERDecode(BufferedTransformation &bt)
+{
+	BERSequenceDecoder seq(bt);
+	m_n.BERDecode(seq);
+	m_r.BERDecode(seq);
+	m_s.BERDecode(seq);
+	seq.MessageEnd();
+}
+
+void RabinFunction::DEREncode(BufferedTransformation &bt) const
+{
+	DERSequenceEncoder seq(bt);
+	m_n.DEREncode(seq);
+	m_r.DEREncode(seq);
+	m_s.DEREncode(seq);
+	seq.MessageEnd();
+}
+
+Integer RabinFunction::ApplyFunction(const Integer &in) const
+{
+	DoQuickSanityCheck();
+
+	Integer out = in.Squared()%m_n;
+	if (in.IsOdd())
+		out = out*m_r%m_n;
+	if (Jacobi(in, m_n)==-1)
+		out = out*m_s%m_n;
+	return out;
+}
+
+bool RabinFunction::Validate(RandomNumberGenerator &rng, unsigned int level) const
+{
+	bool pass = true;
+	pass = pass && m_n > Integer::One() && m_n%4 == 1;
+	pass = pass && m_r > Integer::One() && m_r < m_n;
+	pass = pass && m_s > Integer::One() && m_s < m_n;
+	if (level >= 1)
+		pass = pass && Jacobi(m_r, m_n) == -1 && Jacobi(m_s, m_n) == -1;
+	return pass;
+}
+
+bool RabinFunction::GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
+{
+	return GetValueHelper(this, name, valueType, pValue).Assignable()
+		CRYPTOPP_GET_FUNCTION_ENTRY(Modulus)
+		CRYPTOPP_GET_FUNCTION_ENTRY(QuadraticResidueModPrime1)
+		CRYPTOPP_GET_FUNCTION_ENTRY(QuadraticResidueModPrime2)
+		;
+}
+
+void RabinFunction::AssignFrom(const NameValuePairs &source)
+{
+	AssignFromHelper(this, source)
+		CRYPTOPP_SET_FUNCTION_ENTRY(Modulus)
+		CRYPTOPP_SET_FUNCTION_ENTRY(QuadraticResidueModPrime1)
+		CRYPTOPP_SET_FUNCTION_ENTRY(QuadraticResidueModPrime2)
+		;
+}
+
+// *****************************************************************************
+// private key operations:
+
+// generate a random private key
+void InvertibleRabinFunction::GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg)
+{
+	int modulusSize = 2048;
+	alg.GetIntValue("ModulusSize", modulusSize) || alg.GetIntValue("KeySize", modulusSize);
+
+	if (modulusSize < 16)
+		throw InvalidArgument("InvertibleRabinFunction: specified modulus size is too small");
+
+	// VC70 workaround: putting these after primeParam causes overlapped stack allocation
+	bool rFound=false, sFound=false;
+	Integer t=2;
+
+	const NameValuePairs &primeParam = MakeParametersForTwoPrimesOfEqualSize(modulusSize)
+		("EquivalentTo", 3)("Mod", 4);
+	m_p.GenerateRandom(rng, primeParam);
+	m_q.GenerateRandom(rng, primeParam);
+
+	while (!(rFound && sFound))
+	{
+		int jp = Jacobi(t, m_p);
+		int jq = Jacobi(t, m_q);
+
+		if (!rFound && jp==1 && jq==-1)
+		{
+			m_r = t;
+			rFound = true;
+		}
+
+		if (!sFound && jp==-1 && jq==1)
+		{
+			m_s = t;
+			sFound = true;
+		}
+
+		++t;
+	}
+
+	m_n = m_p * m_q;
+	m_u = m_q.InverseMod(m_p);
+}
+
+void InvertibleRabinFunction::BERDecode(BufferedTransformation &bt)
+{
+	BERSequenceDecoder seq(bt);
+	m_n.BERDecode(seq);
+	m_r.BERDecode(seq);
+	m_s.BERDecode(seq);
+	m_p.BERDecode(seq);
+	m_q.BERDecode(seq);
+	m_u.BERDecode(seq);
+	seq.MessageEnd();
+}
+
+void InvertibleRabinFunction::DEREncode(BufferedTransformation &bt) const
+{
+	DERSequenceEncoder seq(bt);
+	m_n.DEREncode(seq);
+	m_r.DEREncode(seq);
+	m_s.DEREncode(seq);
+	m_p.DEREncode(seq);
+	m_q.DEREncode(seq);
+	m_u.DEREncode(seq);
+	seq.MessageEnd();
+}
+
+Integer InvertibleRabinFunction::CalculateInverse(const Integer &in) const
+{
+	DoQuickSanityCheck();
+
+	Integer cp=in%m_p, cq=in%m_q;
+
+	int jp = Jacobi(cp, m_p);
+	int jq = Jacobi(cq, m_q);
+
+	if (jq==-1)
+	{
+		cp = cp*EuclideanMultiplicativeInverse(m_r, m_p)%m_p;
+		cq = cq*EuclideanMultiplicativeInverse(m_r, m_q)%m_q;
+	}
+
+	if (jp==-1)
+	{
+		cp = cp*EuclideanMultiplicativeInverse(m_s, m_p)%m_p;
+		cq = cq*EuclideanMultiplicativeInverse(m_s, m_q)%m_q;
+	}
+
+	cp = ModularSquareRoot(cp, m_p);
+	cq = ModularSquareRoot(cq, m_q);
+
+	if (jp==-1)
+		cp = m_p-cp;
+
+	Integer out = CRT(cq, m_q, cp, m_p, m_u);
+
+	if ((jq==-1 && out.IsEven()) || (jq==1 && out.IsOdd()))
+		out = m_n-out;
+
+	return out;
+}
+
+bool InvertibleRabinFunction::Validate(RandomNumberGenerator &rng, unsigned int level) const
+{
+	bool pass = RabinFunction::Validate(rng, level);
+	pass = pass && m_p > Integer::One() && m_p%4 == 3 && m_p < m_n;
+	pass = pass && m_q > Integer::One() && m_q%4 == 3 && m_q < m_n;
+	pass = pass && m_u.IsPositive() && m_u < m_p;
+	if (level >= 1)
+	{
+		pass = pass && m_p * m_q == m_n;
+		pass = pass && m_u * m_q % m_p == 1;
+		pass = pass && Jacobi(m_r, m_p) == 1;
+		pass = pass && Jacobi(m_r, m_q) == -1;
+		pass = pass && Jacobi(m_s, m_p) == -1;
+		pass = pass && Jacobi(m_s, m_q) == 1;
+	}
+	if (level >= 2)
+		pass = pass && VerifyPrime(rng, m_p, level-2) && VerifyPrime(rng, m_q, level-2);
+	return pass;
+}
+
+bool InvertibleRabinFunction::GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
+{
+	return GetValueHelper<RabinFunction>(this, name, valueType, pValue).Assignable()
+		CRYPTOPP_GET_FUNCTION_ENTRY(Prime1)
+		CRYPTOPP_GET_FUNCTION_ENTRY(Prime2)
+		CRYPTOPP_GET_FUNCTION_ENTRY(MultiplicativeInverseOfPrime2ModPrime1)
+		;
+}
+
+void InvertibleRabinFunction::AssignFrom(const NameValuePairs &source)
+{
+	AssignFromHelper<RabinFunction>(this, source)
+		CRYPTOPP_SET_FUNCTION_ENTRY(Prime1)
+		CRYPTOPP_SET_FUNCTION_ENTRY(Prime2)
+		CRYPTOPP_SET_FUNCTION_ENTRY(MultiplicativeInverseOfPrime2ModPrime1)
+		;
+}
+
+NAMESPACE_END