diff -r 641f389e9157 -r a71299154b21 crypto/weakcrypto/source/bigint/mont.cpp --- a/crypto/weakcrypto/source/bigint/mont.cpp Tue Aug 31 17:00:08 2010 +0300 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,235 +0,0 @@ -/* -* Copyright (c) 2003-2009 Nokia Corporation and/or its subsidiary(-ies). -* All rights reserved. -* This component and the accompanying materials are made available -* under the terms of the License "Eclipse Public License v1.0" -* which accompanies this distribution, and is available -* at the URL "http://www.eclipse.org/legal/epl-v10.html". -* -* Initial Contributors: -* Nokia Corporation - initial contribution. -* -* Contributors: -* -* Description: -* -*/ - - -#include -#include -#include "algorithms.h" -#include "words.h" -#include "windowslider.h" -#include "mont.h" - -CMontgomeryStructure* CMontgomeryStructure::NewL( - const TInteger& aModulus) - { - CMontgomeryStructure* self = CMontgomeryStructure::NewLC(aModulus); - CleanupStack::Pop(self); - return self; - } - -CMontgomeryStructure* CMontgomeryStructure::NewLC( - const TInteger& aModulus) - { - CMontgomeryStructure* self = new(ELeave) CMontgomeryStructure; - CleanupStack::PushL(self); - self->ConstructL(aModulus); - return self; - } - -CMontgomeryStructure::~CMontgomeryStructure() - { - iModulus.Close(); - iModulusInv.Close(); - iWorkspace.Close(); - iResult.Close(); - } - -void CMontgomeryStructure::ConstructL(const TInteger& aModulus) - { - User::LeaveIfError(aModulus.IsOdd() ? KErrNone : KErrArgument); - - iModulusInv = RInteger::NewEmptyL(aModulus.Size()); - iWorkspace = RInteger::NewEmptyL(5*aModulus.Size()); - iModulus = RInteger::NewL(aModulus); - iResult = RInteger::NewEmptyL(aModulus.Size()); - RecursiveInverseModPower2(iModulusInv.Ptr(), iWorkspace.Ptr(), - iModulus.Ptr(), iModulus.Size()); - } - -CMontgomeryStructure::CMontgomeryStructure() - { - } - -TInteger& CMontgomeryStructure::ConvertInL(TInteger& aInteger) const - { - aInteger <<= WordsToBits(iModulus.Size()); - aInteger %= iModulus; - return aInteger; - } - -TInteger& CMontgomeryStructure::ConvertOutL(TInteger& aInteger) const - { - TUint* const T = iWorkspace.Ptr(); - TUint* const R = aInteger.Ptr(); - const TUint N = iModulus.Size(); - User::LeaveIfError((aInteger.Size() <= N) ? KErrNone : KErrArgument); - - CopyWords(T, aInteger.Ptr(), aInteger.Size()); - SetWords(T + aInteger.Size(), 0, 2*N - aInteger.Size()); - MontgomeryReduce(R, T+2*N, T, iModulus.Ptr(), iModulusInv.Ptr(), N); - return aInteger; - } - -const TInteger& CMontgomeryStructure::ReduceL( - const TInteger& aInteger) const - { - RInteger temp = RInteger::NewL(aInteger); - CleanupStack::PushL(temp); - ConvertInL(temp); - iResult.CopyL(ConvertOutL(temp), EFalse); - CleanupStack::PopAndDestroy(&temp); - return iResult; - } - -const TInteger& CMontgomeryStructure::MultiplyL(const TInteger& aA, - const TInteger& aB) const - { - RInteger a = RInteger::NewL(aA); - CleanupStack::PushL(a); - RInteger b = RInteger::NewL(aB); - CleanupStack::PushL(b); - DoMultiplyL(iResult, ConvertInL(a), ConvertInL(b)); - ConvertOutL(iResult); - CleanupStack::PopAndDestroy(&b); - CleanupStack::PopAndDestroy(&a); - return iResult; - } - -void CMontgomeryStructure::DoMultiplyL(TInteger& aResult, const TInteger& aA, - const TInteger& aB) const - { - User::LeaveIfError((aResult.Size() == iModulus.Size()) ? KErrNone : KErrArgument); - - TUint* const T = iWorkspace.Ptr(); - TUint* const R = aResult.Ptr(); - const TUint N = iModulus.Size(); - const TUint* const aReg = aA.Ptr(); - const TUint* const bReg = aB.Ptr(); - const TUint aSize = aA.Size(); - const TUint bSize = aB.Size(); - User::LeaveIfError((aSize <= N && bSize <= N) ? KErrNone : KErrArgument); - - AsymmetricMultiply(T, T+2*N, aReg, aSize, bReg, bSize); - SetWords(T+aSize+bSize, 0, 2*N - aSize - bSize); - MontgomeryReduce(R, T+2*N, T, iModulus.Ptr(), iModulusInv.Ptr(), N); - } - -const TInteger& CMontgomeryStructure::SquareL(const TInteger& aA) const - { - RInteger a = RInteger::NewL(aA); - CleanupStack::PushL(a); - DoSquareL(iResult, ConvertInL(a)); - ConvertOutL(iResult); - CleanupStack::PopAndDestroy(&a); - return iResult; - } - -void CMontgomeryStructure::DoSquareL(TInteger& aResult, const TInteger& aA) const - { - User::LeaveIfError((aResult.Size() == iModulus.Size()) ? KErrNone : KErrArgument); - TUint* const T = iWorkspace.Ptr(); - TUint* const R = aResult.Ptr(); - const TUint N = iModulus.Size(); - const TUint* const aReg = aA.Ptr(); - const TUint aSize = aA.Size(); - - User::LeaveIfError((aSize <= N) ? KErrNone : KErrArgument); - - RecursiveSquare(T, T+2*N, aReg, aSize); - SetWords(T+2*aSize, 0, 2*N-2*aSize); - MontgomeryReduce(R, T+2*N, T, iModulus.Ptr(), iModulusInv.Ptr(), N); - } - -const TInteger& CMontgomeryStructure::ExponentiateL( - const TInteger& aBase, const TInteger& aExponent) const - { - //See HAC 14.85 - if ((iResult.Size() != iModulus.Size()) || - (aBase >= iModulus) || - (!aBase.IsPositive()) || - (!aExponent.IsPositive())) - { - User::Leave(KErrArgument); - } - - // 1.1 Precomputation - // g1 <- g - // g2 <- g^2 - RInteger g2 = RInteger::NewL(aBase); - CleanupStack::PushL(g2); - ConvertInL(g2); - //ConvertIn can shrink g2, because we call DoSquare on g2, g2 must be the same size as the modulus - g2.CleanGrowL(iModulus.Size()); - RInteger g1 = RInteger::NewL(g2); - CleanupStack::PushL(g1); - DoSquareL(g2, g2); - - TWindowSlider slider(aExponent); - - // 1.2 - // For i from 1 to (2^(k-1) -1) do g2i+1 <- g2i-1 * g2 - TUint count = (1 << (slider.WindowSize()-1)) - 1; //2^(k-1) -1 - RRArray powerArray(count+1); //+1 because we append g1 - User::LeaveIfError(powerArray.Append(g1)); - CleanupStack::Pop(&g1); - CleanupClosePushL(powerArray); - for(TUint k=1; k <= count; k++) - { - RInteger gi = RInteger::NewEmptyL(iModulus.Size()); - DoMultiplyL(gi, g2, powerArray[k-1]); - User::LeaveIfError(powerArray.Append(gi)); - } - - // 2 A <- 1, i <- t - RInteger temp = RInteger::NewL(TInteger::One()); - CleanupStack::PushL(temp); - ConvertInL(temp); - - RInteger& A = iResult; - //Set A to one converted in for this modulus without changing the memory size of A (iResult) - A.CopyL(temp, EFalse); - CleanupStack::PopAndDestroy(&temp); - - TInt i = aExponent.BitCount() - 1; - - // 3 While i>=0 do: - while( i>=0 ) - { - // 3.1 If ei == 0 then A <- A^2 - if(!aExponent.Bit(i)) - { - DoSquareL(A, A); - i--; - } - // 3.2 Find longest bitstring ei,ei-1,...,el s.t. i-l+1<=k and el==1 - // and do: - // A <- (A^2^(i-l+1)) * g[the index indicated by the bitstring value] - else - { - slider.FindNextWindow(i); - assert(slider.Length() >= 1); - for(TUint j=0; j>1]); - i -= slider.Length(); - } - } - CleanupStack::PopAndDestroy(2, &g2); //powerArray, g2 - return ConvertOutL(A); // A == iResult - }