sl@0: /*
sl@0: * Copyright (c) 2003-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: * All rights reserved.
sl@0: * This component and the accompanying materials are made available
sl@0: * under the terms of the License "Eclipse Public License v1.0"
sl@0: * which accompanies this distribution, and is available
sl@0: * at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: *
sl@0: * Initial Contributors:
sl@0: * Nokia Corporation - initial contribution.
sl@0: *
sl@0: * Contributors:
sl@0: *
sl@0: * Description: 
sl@0: *
sl@0: */
sl@0: 
sl@0: 
sl@0: #include <asymmetrickeys.h>
sl@0: #include <bigint.h>
sl@0: #include <random.h>
sl@0: #include <hash.h>
sl@0: #include "../common/inlines.h"
sl@0: #include "../bigint/mont.h"
sl@0: #include "dsakeypairshim.h"
sl@0: 
sl@0: const TUint SHASIZE = 20;
sl@0: const TUint KMinPrimeLength = 512;
sl@0: const TUint KMaxPrimeLength = 1024;
sl@0: const TUint KPrimeLengthMultiple = 64;
sl@0: 
sl@0: /* CDSAParameters */
sl@0: 
sl@0: EXPORT_C const TInteger& CDSAParameters::P(void) const
sl@0: 	{
sl@0: 	return iP;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C const TInteger& CDSAParameters::Q(void) const
sl@0: 	{
sl@0: 	return iQ;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C const TInteger& CDSAParameters::G(void) const
sl@0: 	{
sl@0: 	return iG;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAParameters::~CDSAParameters(void)
sl@0: 	{
sl@0: 	iP.Close();
sl@0: 	iQ.Close();
sl@0: 	iG.Close();
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAParameters* CDSAParameters::NewL(RInteger& aP, RInteger& aQ, 
sl@0: 	RInteger& aG)
sl@0: 	{
sl@0: 	CDSAParameters* me = new (ELeave) CDSAParameters(aP, aQ, aG);
sl@0: 	return (me);
sl@0: 	}
sl@0: 
sl@0: EXPORT_C TBool CDSAParameters::ValidatePrimesL(const CDSAPrimeCertificate& aCert)
sl@0: 	const
sl@0: 	{
sl@0: 	TBool result = EFalse;
sl@0: 	RInteger p;
sl@0: 	RInteger q;
sl@0: 	//Regenerate primes using aCert's seed and counter
sl@0: 	TUint counter = aCert.Counter();
sl@0: 	if(!CDSAParameters::GeneratePrimesL(aCert.Seed(), counter, p, 
sl@0: 		P().BitCount(), q, ETrue))
sl@0: 		{
sl@0: 		return result;
sl@0: 		}
sl@0: 	//this doesn't leave, no need to push p and q
sl@0: 	if(p == P() && q == Q() && counter == aCert.Counter())
sl@0: 		{
sl@0: 		result = ETrue;
sl@0: 		}
sl@0: 	p.Close();
sl@0: 	q.Close();
sl@0: 	return result;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C TBool CDSAParameters::ValidPrimeLength(TUint aPrimeBits)
sl@0: 	{
sl@0: 	return (aPrimeBits >= KMinPrimeLength &&
sl@0: 		aPrimeBits <= KMaxPrimeLength &&
sl@0: 		aPrimeBits % KPrimeLengthMultiple == 0);
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAParameters::CDSAParameters(RInteger& aP, RInteger& aQ, 	
sl@0: 	RInteger& aG) : iP(aP), iQ(aQ), iG(aG)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAParameters::CDSAParameters(void)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: TBool CDSAParameters::GeneratePrimesL(const TDesC8& aSeed, TUint& aCounter, 
sl@0: 	RInteger& aP, TUint aL, RInteger& aQ, TBool aUseInputCounter)
sl@0: 	{
sl@0: 	//This follows the steps in FIPS 186-2 
sl@0: 	//See DSS Appendix 2.2
sl@0: 	//Note. Step 1 is performed prior to calling GeneratePrimesL, so that this
sl@0: 	//routine can be used for both generation and validation.
sl@0: 	//Step 1.  Choose an arbitrary sequence of at least 160 bits and call it
sl@0: 	//SEED.  Let g be the length of SEED in bits.
sl@0: 
sl@0: 	if(!CDSAParameters::ValidPrimeLength(aL))
sl@0: 		{
sl@0: 		User::Leave(KErrNotSupported);
sl@0: 		}
sl@0: 	
sl@0: 	CSHA1* sha1 = CSHA1::NewL();
sl@0: 	CleanupStack::PushL(sha1);
sl@0: 
sl@0: 	HBufC8* seedBuf = aSeed.AllocLC();
sl@0: 	TPtr8 seed = seedBuf->Des();
sl@0: 	TUint gBytes = aSeed.Size();
sl@0: 	//Note that the DSS's g = BytesToBits(gBytes) ie. the number of random bits
sl@0: 	//in the seed.  
sl@0: 	//This function has made the assumption (for ease of computation) that g%8
sl@0: 	//is 0.  Ie the seed is a whole number of random bytes.
sl@0: 	TBuf8<SHASIZE> U; 
sl@0: 	TBuf8<SHASIZE> temp; 
sl@0: 	const TUint n = (aL-1)/160;
sl@0: 	const TUint b = (aL-1)%160;
sl@0: 	HBufC8* Wbuf = HBufC8::NewMaxLC((n+1) * SHASIZE);
sl@0: 	TUint8* W = const_cast<TUint8*>(Wbuf->Ptr());
sl@0: 
sl@0: 	U.Copy(sha1->Final(seed));
sl@0: 	
sl@0: 	//Step 2. U = SHA-1[SEED] XOR SHA-1[(SEED+1) mod 2^g]
sl@0: 	for(TInt i=gBytes - 1, carry=ETrue; i>=0 && carry; i--)
sl@0: 		{
sl@0: 		//!++(TUint) adds one to the current word which if it overflows to zero
sl@0: 		//sets carry to 1 thus letting the loop continue.  It's a poor man's
sl@0: 		//multi-word addition.  Swift eh?
sl@0: 		carry = !++(seed[i]);
sl@0: 		}
sl@0: 
sl@0: 	temp.Copy(sha1->Final(seed));
sl@0: 	XorBuf(const_cast<TUint8*>(U.Ptr()), temp.Ptr(), SHASIZE);
sl@0: 
sl@0: 	//Step 3. Form q from U by setting the most significant bit (2^159)
sl@0: 	//and the least significant bit to 1.
sl@0: 	U[0] |= 0x80;
sl@0: 	U[SHASIZE-1] |= 1;
sl@0: 
sl@0: 	aQ = RInteger::NewL(U);
sl@0: 	CleanupStack::PushL(aQ);
sl@0: 
sl@0: 	//Step 4. Use a robust primality testing algo to test if q is prime
sl@0: 	//The robust part is the calling codes problem.  This will use whatever
sl@0: 	//random number generator you set for the thread.  To attempt FIPS 186-2
sl@0: 	//compliance, set a FIPS 186-2 compliant RNG.
sl@0: 	if( !aQ.IsPrimeL() )
sl@0: 		{
sl@0: 		//Step 5. If not exit and get a new seed
sl@0: 		CleanupStack::PopAndDestroy(&aQ);
sl@0: 		CleanupStack::PopAndDestroy(Wbuf);
sl@0: 		CleanupStack::PopAndDestroy(seedBuf);
sl@0: 		CleanupStack::PopAndDestroy(sha1);
sl@0: 		return EFalse;
sl@0: 		}
sl@0: 	
sl@0: 	TUint counterEnd = aUseInputCounter ? aCounter+1 : 4096;
sl@0: 	
sl@0: 	//Step 6. Let counter = 0 and offset = 2
sl@0: 	//Note 1. that the DSS speaks of SEED + offset + k because they always
sl@0: 	//refer to a constant SEED.  We update our seed as we go so the offset
sl@0: 	//variable has already been added to seed in the previous iterations.
sl@0: 	//Note 2. We've already added 1 to our seed, so the first time through this
sl@0: 	//the offset in DSS speak will be 2.
sl@0: 	for(TUint counter=0; counter < counterEnd; counter++)
sl@0: 		{
sl@0: 		//Step 7. For k=0, ..., n let
sl@0: 		// Vk = SHA-1[(SEED + offset + k) mod 2^g]
sl@0: 		//I'm storing the Vk's inside of a big W buffer.
sl@0: 		for(TUint k=0; k<=n; k++)
sl@0: 			{
sl@0: 			for(TInt i=gBytes-1, carry=ETrue; i>=0 && carry; i--)
sl@0: 				{
sl@0: 				carry = !++(seed[i]);
sl@0: 				}
sl@0: 			if(!aUseInputCounter || counter == aCounter)
sl@0: 				{
sl@0: 				TPtr8 Wptr(W+(n-k)*SHASIZE, gBytes);
sl@0: 				Wptr.Copy(sha1->Final(seed));
sl@0: 				}
sl@0: 			}
sl@0: 		if(!aUseInputCounter || counter == aCounter)
sl@0: 			{
sl@0: 			//Step 8. Let W be the integer...  and let X = W + 2^(L-1)
sl@0: 			const_cast<TUint8&>((*Wbuf)[SHASIZE - 1 - b/8]) |= 0x80;
sl@0: 			TPtr8 Wptr(W + SHASIZE - 1 - b/8, aL/8, aL/8);
sl@0: 			RInteger X = RInteger::NewL(Wptr);
sl@0: 			CleanupStack::PushL(X);
sl@0: 			//Step 9. Let c = X mod 2q and set p = X - (c-1)
sl@0: 			RInteger twoQ = aQ.TimesL(TInteger::Two());
sl@0: 			CleanupStack::PushL(twoQ);
sl@0: 			RInteger c = X.ModuloL(twoQ);
sl@0: 			CleanupStack::PushL(c);
sl@0: 			--c;
sl@0: 			aP = X.MinusL(c);
sl@0: 			CleanupStack::PopAndDestroy(3, &X); //twoQ, c, X
sl@0: 			CleanupStack::PushL(aP);
sl@0: 			
sl@0: 			//Step 10 and 11: if p >= 2^(L-1) and p is prime
sl@0: 			if( aP.Bit(aL-1) && aP.IsPrimeL() )
sl@0: 				{
sl@0: 				aCounter = counter;
sl@0: 				CleanupStack::Pop(&aP);
sl@0: 				CleanupStack::Pop(&aQ);
sl@0: 				CleanupStack::PopAndDestroy(Wbuf);
sl@0: 				CleanupStack::PopAndDestroy(seedBuf);
sl@0: 				CleanupStack::PopAndDestroy(sha1);
sl@0: 				return ETrue;
sl@0: 				}
sl@0: 			CleanupStack::PopAndDestroy(&aP);
sl@0: 			}
sl@0: 		}
sl@0: 	CleanupStack::PopAndDestroy(&aQ);
sl@0: 	CleanupStack::PopAndDestroy(Wbuf);
sl@0: 	CleanupStack::PopAndDestroy(seedBuf);
sl@0: 	CleanupStack::PopAndDestroy(sha1);
sl@0: 	return EFalse;
sl@0: 	}
sl@0: 
sl@0: /* CDSAPublicKey */
sl@0: 
sl@0: EXPORT_C CDSAPublicKey* CDSAPublicKey::NewL(RInteger& aP, RInteger& aQ, 
sl@0: 	RInteger& aG, RInteger& aY)
sl@0: 	{
sl@0: 	CDSAPublicKey* self = new(ELeave) CDSAPublicKey(aP, aQ, aG, aY);
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAPublicKey* CDSAPublicKey::NewLC(RInteger& aP, RInteger& aQ, 
sl@0: 	RInteger& aG, RInteger& aY)
sl@0: 	{
sl@0: 	CDSAPublicKey* self = NewL(aP, aQ, aG, aY);
sl@0: 	CleanupStack::PushL(self);
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C const TInteger& CDSAPublicKey::Y(void) const
sl@0: 	{
sl@0: 	return iY;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAPublicKey::CDSAPublicKey(void)
sl@0: 	{
sl@0: 	} 
sl@0: 
sl@0: EXPORT_C CDSAPublicKey::CDSAPublicKey(RInteger& aP, RInteger& aQ, RInteger& aG, 
sl@0: 	RInteger& aY) : CDSAParameters(aP, aQ, aG), iY(aY)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAPublicKey::~CDSAPublicKey(void)
sl@0: 	{
sl@0: 	iY.Close();
sl@0: 	}
sl@0: 
sl@0: /* CDSAPrivateKey */
sl@0: 
sl@0: EXPORT_C CDSAPrivateKey* CDSAPrivateKey::NewL(RInteger& aP, RInteger& aQ, 
sl@0: 	RInteger& aG, RInteger& aX)
sl@0: 	{
sl@0: 	CDSAPrivateKey* self = new(ELeave) CDSAPrivateKey(aP, aQ, aG, aX);
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAPrivateKey* CDSAPrivateKey::NewLC(RInteger& aP, RInteger& aQ, 
sl@0: 	RInteger& aG, RInteger& aX)
sl@0: 	{
sl@0: 	CDSAPrivateKey* self = NewL(aP, aQ, aG, aX);
sl@0: 	CleanupStack::PushL(self);
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C const TInteger& CDSAPrivateKey::X(void) const
sl@0: 	{
sl@0: 	return iX;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAPrivateKey::CDSAPrivateKey(RInteger& aP, RInteger& aQ, RInteger& aG, 
sl@0: 	RInteger& aX) : CDSAParameters(aP, aQ, aG), iX(aX)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAPrivateKey::~CDSAPrivateKey(void)
sl@0: 	{
sl@0: 	iX.Close();
sl@0: 	}
sl@0: 
sl@0: /* CDSAKeyPair */
sl@0: 
sl@0: EXPORT_C CDSAKeyPair* CDSAKeyPair::NewL(TUint aKeyBits)
sl@0: 	{
sl@0:  	CDSAKeyPairShim* self = CDSAKeyPairShim::NewLC(aKeyBits);
sl@0:  	CleanupStack::Pop();
sl@0:  	return self;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAKeyPair* CDSAKeyPair::NewLC(TUint aKeyBits)
sl@0: 	{
sl@0:  	CDSAKeyPairShim* self = CDSAKeyPairShim::NewLC(aKeyBits);
sl@0:  	return self;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C const CDSAPublicKey& CDSAKeyPair::PublicKey(void) const
sl@0: 	{
sl@0: 	return *iPublic;
sl@0: 	}
sl@0: 	
sl@0: EXPORT_C const CDSAPrivateKey& CDSAKeyPair::PrivateKey(void) const
sl@0: 	{
sl@0: 	return *iPrivate;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAKeyPair::~CDSAKeyPair(void) 
sl@0: 	{
sl@0: 	delete iPublic;
sl@0: 	delete iPrivate;
sl@0: 	delete iPrimeCertificate;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAKeyPair::CDSAKeyPair(void) 
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: EXPORT_C const CDSAPrimeCertificate& CDSAKeyPair::PrimeCertificate(void) const
sl@0: 	{
sl@0: 	return *iPrimeCertificate;
sl@0: 	}
sl@0: 
sl@0: /* CDSAPrimeCertificate */
sl@0: 
sl@0: EXPORT_C CDSAPrimeCertificate* CDSAPrimeCertificate::NewL(const TDesC8& aSeed,
sl@0: 	TUint aCounter)
sl@0: 	{
sl@0: 	CDSAPrimeCertificate* self = NewLC(aSeed, aCounter);
sl@0: 	CleanupStack::Pop();
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAPrimeCertificate* CDSAPrimeCertificate::NewLC(const TDesC8& aSeed,
sl@0: 	TUint aCounter)
sl@0: 	{
sl@0: 	CDSAPrimeCertificate* self = new(ELeave) CDSAPrimeCertificate(aCounter);
sl@0: 	CleanupStack::PushL(self);
sl@0: 	self->ConstructL(aSeed);
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C const TDesC8& CDSAPrimeCertificate::Seed(void) const
sl@0: 	{
sl@0: 	return *iSeed;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C TUint CDSAPrimeCertificate::Counter(void) const
sl@0: 	{
sl@0: 	return iCounter;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAPrimeCertificate::~CDSAPrimeCertificate(void) 
sl@0: 	{
sl@0: 	delete const_cast<HBufC8*>(iSeed);
sl@0: 	}
sl@0: 
sl@0: void CDSAPrimeCertificate::ConstructL(const TDesC8& aSeed)
sl@0: 	{
sl@0: 	iSeed = aSeed.AllocL();
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAPrimeCertificate::CDSAPrimeCertificate(TUint aCounter) 
sl@0: 	: iCounter(aCounter)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: // Over taken by  shim version. so, exclude it from coverage.
sl@0: #ifdef _BullseyeCoverage
sl@0: #pragma suppress_warnings on
sl@0: #pragma BullseyeCoverage off
sl@0: #pragma suppress_warnings off
sl@0: #endif
sl@0: void CDSAKeyPair::ConstructL(TUint /*aPBits*/)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: // Unused exported and protected method can be excluded from coverage.
sl@0: EXPORT_C CDSAPrimeCertificate::CDSAPrimeCertificate(void) 
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CDSAPrivateKey::CDSAPrivateKey(void)
sl@0: 	{
sl@0: 	}