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diff --git a/CryptoPP/rabin.cpp b/CryptoPP/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 "modarith.h"
+
+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;
+
+ AlgorithmParameters 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(RandomNumberGenerator &rng, const Integer &in) const
+{
+ DoQuickSanityCheck();
+
+ ModularArithmetic modn(m_n);
+ Integer r(rng, Integer::One(), m_n - Integer::One());
+ r = modn.Square(r);
+ Integer r2 = modn.Square(r);
+ Integer c = modn.Multiply(in, r2); // blind
+
+ Integer cp=c%m_p, cq=c%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);
+
+ out = modn.Divide(out, r); // unblind
+
+ 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