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Diffstat (limited to 'mysql/extra/yassl/taocrypt/include/modarith.hpp')
-rw-r--r-- | mysql/extra/yassl/taocrypt/include/modarith.hpp | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/mysql/extra/yassl/taocrypt/include/modarith.hpp b/mysql/extra/yassl/taocrypt/include/modarith.hpp new file mode 100644 index 0000000..5ac3f67 --- /dev/null +++ b/mysql/extra/yassl/taocrypt/include/modarith.hpp @@ -0,0 +1,165 @@ +/* + Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; see the file COPYING. If not, write to the + Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, + MA 02110-1301 USA. +*/ + + +/* based on Wei Dai's modarith.h from CryptoPP */ + + +#ifndef TAO_CRYPT_MODARITH_HPP +#define TAO_CRYPT_MODARITH_HPP + +#include "misc.hpp" +#include "algebra.hpp" + +namespace TaoCrypt { + + +// ModularArithmetic +class ModularArithmetic : public AbstractRing +{ +public: + + typedef int RandomizationParameter; + typedef Integer Element; + + ModularArithmetic(const Integer &modulus = Integer::One()) + : modulus(modulus), result((word)0, modulus.reg_.size()) {} + + ModularArithmetic(const ModularArithmetic &ma) + : AbstractRing(), + modulus(ma.modulus), result((word)0, modulus.reg_.size()) {} + + const Integer& GetModulus() const {return modulus;} + void SetModulus(const Integer &newModulus) + { + modulus = newModulus; + result.reg_.resize(modulus.reg_.size()); + } + + virtual bool IsMontgomeryRepresentation() const {return false;} + + virtual Integer ConvertIn(const Integer &a) const + {return a%modulus;} + + virtual Integer ConvertOut(const Integer &a) const + {return a;} + + const Integer& Half(const Integer &a) const; + + bool Equal(const Integer &a, const Integer &b) const + {return a==b;} + + const Integer& Identity() const + {return Integer::Zero();} + + const Integer& Add(const Integer &a, const Integer &b) const; + + Integer& Accumulate(Integer &a, const Integer &b) const; + + const Integer& Inverse(const Integer &a) const; + + const Integer& Subtract(const Integer &a, const Integer &b) const; + + Integer& Reduce(Integer &a, const Integer &b) const; + + const Integer& Double(const Integer &a) const + {return Add(a, a);} + + const Integer& MultiplicativeIdentity() const + {return Integer::One();} + + const Integer& Multiply(const Integer &a, const Integer &b) const + {return result1 = a*b%modulus;} + + const Integer& Square(const Integer &a) const + {return result1 = a.Squared()%modulus;} + + bool IsUnit(const Integer &a) const + {return Integer::Gcd(a, modulus).IsUnit();} + + const Integer& MultiplicativeInverse(const Integer &a) const + {return result1 = a.InverseMod(modulus);} + + const Integer& Divide(const Integer &a, const Integer &b) const + {return Multiply(a, MultiplicativeInverse(b));} + + Integer CascadeExponentiate(const Integer &x, const Integer &e1, + const Integer &y, const Integer &e2) const; + + void SimultaneousExponentiate(Element *results, const Element &base, + const Integer *exponents, unsigned int exponentsCount) const; + + unsigned int MaxElementBitLength() const + {return (modulus-1).BitCount();} + + unsigned int MaxElementByteLength() const + {return (modulus-1).ByteCount();} + + + static const RandomizationParameter DefaultRandomizationParameter; + +protected: + Integer modulus; + mutable Integer result, result1; + +}; + + + +//! do modular arithmetics in Montgomery representation for increased speed +class MontgomeryRepresentation : public ModularArithmetic +{ +public: + MontgomeryRepresentation(const Integer &modulus); // modulus must be odd + + bool IsMontgomeryRepresentation() const {return true;} + + Integer ConvertIn(const Integer &a) const + {return (a<<(WORD_BITS*modulus.reg_.size()))%modulus;} + + Integer ConvertOut(const Integer &a) const; + + const Integer& MultiplicativeIdentity() const + {return result1 = Integer::Power2(WORD_BITS*modulus.reg_.size())%modulus;} + + const Integer& Multiply(const Integer &a, const Integer &b) const; + + const Integer& Square(const Integer &a) const; + + const Integer& MultiplicativeInverse(const Integer &a) const; + + Integer CascadeExponentiate(const Integer &x, const Integer &e1, + const Integer &y, const Integer &e2) const + {return AbstractRing::CascadeExponentiate(x, e1, y, e2);} + + void SimultaneousExponentiate(Element *results, const Element &base, + const Integer *exponents, unsigned int exponentsCount) const + {AbstractRing::SimultaneousExponentiate(results, base, + exponents, exponentsCount);} + +private: + Integer u; + mutable AlignedWordBlock workspace; +}; + + + + +} // namespace + +#endif // TAO_CRYPT_MODARITH_HPP |