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-rw-r--r--CryptoPP/rw.cpp196
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diff --git a/CryptoPP/rw.cpp b/CryptoPP/rw.cpp
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+// rw.cpp - written and placed in the public domain by Wei Dai
+
+#include "pch.h"
+#include "rw.h"
+#include "nbtheory.h"
+#include "asn.h"
+
+#ifndef CRYPTOPP_IMPORTS
+
+NAMESPACE_BEGIN(CryptoPP)
+
+void RWFunction::BERDecode(BufferedTransformation &bt)
+{
+ BERSequenceDecoder seq(bt);
+ m_n.BERDecode(seq);
+ seq.MessageEnd();
+}
+
+void RWFunction::DEREncode(BufferedTransformation &bt) const
+{
+ DERSequenceEncoder seq(bt);
+ m_n.DEREncode(seq);
+ seq.MessageEnd();
+}
+
+Integer RWFunction::ApplyFunction(const Integer &in) const
+{
+ DoQuickSanityCheck();
+
+ Integer out = in.Squared()%m_n;
+ const word r = 12;
+ // this code was written to handle both r = 6 and r = 12,
+ // but now only r = 12 is used in P1363
+ const word r2 = r/2;
+ const word r3a = (16 + 5 - r) % 16; // n%16 could be 5 or 13
+ const word r3b = (16 + 13 - r) % 16;
+ const word r4 = (8 + 5 - r/2) % 8; // n%8 == 5
+ switch (out % 16)
+ {
+ case r:
+ break;
+ case r2:
+ case r2+8:
+ out <<= 1;
+ break;
+ case r3a:
+ case r3b:
+ out.Negate();
+ out += m_n;
+ break;
+ case r4:
+ case r4+8:
+ out.Negate();
+ out += m_n;
+ out <<= 1;
+ break;
+ default:
+ out = Integer::Zero();
+ }
+ return out;
+}
+
+bool RWFunction::Validate(RandomNumberGenerator &rng, unsigned int level) const
+{
+ bool pass = true;
+ pass = pass && m_n > Integer::One() && m_n%8 == 5;
+ return pass;
+}
+
+bool RWFunction::GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
+{
+ return GetValueHelper(this, name, valueType, pValue).Assignable()
+ CRYPTOPP_GET_FUNCTION_ENTRY(Modulus)
+ ;
+}
+
+void RWFunction::AssignFrom(const NameValuePairs &source)
+{
+ AssignFromHelper(this, source)
+ CRYPTOPP_SET_FUNCTION_ENTRY(Modulus)
+ ;
+}
+
+// *****************************************************************************
+// private key operations:
+
+// generate a random private key
+void InvertibleRWFunction::GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg)
+{
+ int modulusSize = 2048;
+ alg.GetIntValue("ModulusSize", modulusSize) || alg.GetIntValue("KeySize", modulusSize);
+
+ if (modulusSize < 16)
+ throw InvalidArgument("InvertibleRWFunction: specified modulus length is too small");
+
+ AlgorithmParameters primeParam = MakeParametersForTwoPrimesOfEqualSize(modulusSize);
+ m_p.GenerateRandom(rng, CombinedNameValuePairs(primeParam, MakeParameters("EquivalentTo", 3)("Mod", 8)));
+ m_q.GenerateRandom(rng, CombinedNameValuePairs(primeParam, MakeParameters("EquivalentTo", 7)("Mod", 8)));
+
+ m_n = m_p * m_q;
+ m_u = m_q.InverseMod(m_p);
+}
+
+void InvertibleRWFunction::BERDecode(BufferedTransformation &bt)
+{
+ BERSequenceDecoder seq(bt);
+ m_n.BERDecode(seq);
+ m_p.BERDecode(seq);
+ m_q.BERDecode(seq);
+ m_u.BERDecode(seq);
+ seq.MessageEnd();
+}
+
+void InvertibleRWFunction::DEREncode(BufferedTransformation &bt) const
+{
+ DERSequenceEncoder seq(bt);
+ m_n.DEREncode(seq);
+ m_p.DEREncode(seq);
+ m_q.DEREncode(seq);
+ m_u.DEREncode(seq);
+ seq.MessageEnd();
+}
+
+Integer InvertibleRWFunction::CalculateInverse(RandomNumberGenerator &rng, const Integer &x) const
+{
+ DoQuickSanityCheck();
+ ModularArithmetic modn(m_n);
+ Integer r, rInv;
+ do { // do this in a loop for people using small numbers for testing
+ r.Randomize(rng, Integer::One(), m_n - Integer::One());
+ rInv = modn.MultiplicativeInverse(r);
+ } while (rInv.IsZero());
+ Integer re = modn.Square(r);
+ re = modn.Multiply(re, x); // blind
+
+ Integer cp=re%m_p, cq=re%m_q;
+ if (Jacobi(cp, m_p) * Jacobi(cq, m_q) != 1)
+ {
+ cp = cp.IsOdd() ? (cp+m_p) >> 1 : cp >> 1;
+ cq = cq.IsOdd() ? (cq+m_q) >> 1 : cq >> 1;
+ }
+
+ #pragma omp parallel
+ #pragma omp sections
+ {
+ #pragma omp section
+ cp = ModularSquareRoot(cp, m_p);
+ #pragma omp section
+ cq = ModularSquareRoot(cq, m_q);
+ }
+
+ Integer y = CRT(cq, m_q, cp, m_p, m_u);
+ y = modn.Multiply(y, rInv); // unblind
+ y = STDMIN(y, m_n-y);
+ if (ApplyFunction(y) != x) // check
+ throw Exception(Exception::OTHER_ERROR, "InvertibleRWFunction: computational error during private key operation");
+ return y;
+}
+
+bool InvertibleRWFunction::Validate(RandomNumberGenerator &rng, unsigned int level) const
+{
+ bool pass = RWFunction::Validate(rng, level);
+ pass = pass && m_p > Integer::One() && m_p%8 == 3 && m_p < m_n;
+ pass = pass && m_q > Integer::One() && m_q%8 == 7 && 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;
+ }
+ if (level >= 2)
+ pass = pass && VerifyPrime(rng, m_p, level-2) && VerifyPrime(rng, m_q, level-2);
+ return pass;
+}
+
+bool InvertibleRWFunction::GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
+{
+ return GetValueHelper<RWFunction>(this, name, valueType, pValue).Assignable()
+ CRYPTOPP_GET_FUNCTION_ENTRY(Prime1)
+ CRYPTOPP_GET_FUNCTION_ENTRY(Prime2)
+ CRYPTOPP_GET_FUNCTION_ENTRY(MultiplicativeInverseOfPrime2ModPrime1)
+ ;
+}
+
+void InvertibleRWFunction::AssignFrom(const NameValuePairs &source)
+{
+ AssignFromHelper<RWFunction>(this, source)
+ CRYPTOPP_SET_FUNCTION_ENTRY(Prime1)
+ CRYPTOPP_SET_FUNCTION_ENTRY(Prime2)
+ CRYPTOPP_SET_FUNCTION_ENTRY(MultiplicativeInverseOfPrime2ModPrime1)
+ ;
+}
+
+NAMESPACE_END
+
+#endif