Example #1
0
// Public Decrypt
void RSAFunction::VerifyL(const CKey& aPublicKey,
	const TInteger& aInput, RInteger& aOutput)
	{
	const TInteger& N = aPublicKey.GetBigIntL(KRsaKeyParameterNUid);
	const TInteger& E = aPublicKey.GetBigIntL(KRsaKeyParameterEUid);
	FunctionL(N, E, aInput, aOutput);
	}
Example #2
0
// The CRT version of the RSA Trapdoor Function
void RSAFunction::FunctionCRTL(const CKey& aPrivateKey,
								const TInteger& aInput, RInteger& aOutput)
	{
	const TInteger& N = aPrivateKey.GetBigIntL(KRsaKeyParameterNUid);
	IsInputValidL(aInput, N);

	const TInteger& P = aPrivateKey.GetBigIntL(KRsaKeyParameterPUid);
	const TInteger& Q = aPrivateKey.GetBigIntL(KRsaKeyParameterQUid);
	const TInteger& DP = aPrivateKey.GetBigIntL(KRsaKeyParameterDPUid);
	const TInteger& DQ = aPrivateKey.GetBigIntL(KRsaKeyParameterDQUid);
	const TInteger& QInv = aPrivateKey.GetBigIntL(KRsaKeyParameterQInvUid);

	CMontgomeryStructure* montP = CMontgomeryStructure::NewLC(P);
	CMontgomeryStructure* montQ = CMontgomeryStructure::NewLC(Q);
	
	// m1 = c^(dP) mod(p)
	RInteger inputReduced = aInput.ModuloL(P);
	CleanupStack::PushL(inputReduced);
	const TInteger& m1 = montP->ExponentiateL(inputReduced, DP);
	CleanupStack::PopAndDestroy(&inputReduced);

	// m2 = c^(dQ) mod(Q)
	inputReduced = aInput.ModuloL(Q);
	CleanupStack::PushL(inputReduced);
	const TInteger& m2 = montQ->ExponentiateL(inputReduced, DQ);
	CleanupStack::PopAndDestroy(&inputReduced);
	
	// Calculate CRT
	// h = (m1-m2) qInv mod(p)
	RInteger h = m1.MinusL(m2);
	CleanupStack::PushL(h);
	h *= QInv;
	h %= P;

	// m = m2 + q * h
	h *= Q;
	h += m2;

	aOutput = h;
	CleanupStack::Pop(&h);

	CleanupStack::PopAndDestroy(montQ);
	CleanupStack::PopAndDestroy(montP);
	}
Example #3
0
void CRSAImpl::ConstructL(const CKey& aKey)
	{
	const TInteger& N = aKey.GetBigIntL(KRsaKeyParameterNUid);
	TCrypto::IsAsymmetricWeakEnoughL(N.BitCount());
	CAsymmetricCipherImpl::ConstructL(aKey);
	
	if (! IsValidKeyLengthL(N.ByteCount()))
		{
		User::Leave(KErrKeySize);
		}
	}
Example #4
0
// Private Encrypt
void RSAFunction::SignL(const CKey& aPrivateKey, const TInteger& aInput, RInteger& aOutput)
	{
	if (aPrivateKey.KeyProperty().iKeyType == KRsaPrivateKeyStandardUid)
		{
		const TInteger& N = aPrivateKey.GetBigIntL(KRsaKeyParameterNUid);
		const TInteger& D = aPrivateKey.GetBigIntL(KRsaKeyParameterDUid);
		FunctionL(N, D, aInput, aOutput);
		}
	else if (aPrivateKey.KeyProperty().iKeyType == KRsaPrivateKeyCRTUid)
		{
		FunctionCRTL(aPrivateKey, aInput, aOutput);
		}
	else
	{
		User::Leave(KErrNotSupported);
	}
}