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authormadmaxoft <github@xoft.cz>2014-01-22 22:26:40 +0100
committermadmaxoft <github@xoft.cz>2014-01-22 22:26:40 +0100
commit34f13d589a2ebbcae9230732c7a763b3cdd88b41 (patch)
tree4f7bad4f90ca8f7a896d83951804f0207082cafb /lib/cryptopp/algebra.cpp
parentReplacing CryptoPP with PolarSSL. (diff)
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Diffstat (limited to '')
-rw-r--r--lib/cryptopp/algebra.cpp340
1 files changed, 0 insertions, 340 deletions
diff --git a/lib/cryptopp/algebra.cpp b/lib/cryptopp/algebra.cpp
deleted file mode 100644
index 958e63701..000000000
--- a/lib/cryptopp/algebra.cpp
+++ /dev/null
@@ -1,340 +0,0 @@
-// algebra.cpp - written and placed in the public domain by Wei Dai
-
-#include "pch.h"
-
-#ifndef CRYPTOPP_ALGEBRA_CPP // SunCC workaround: compiler could cause this file to be included twice
-#define CRYPTOPP_ALGEBRA_CPP
-
-#include "algebra.h"
-#include "integer.h"
-
-#include <vector>
-
-NAMESPACE_BEGIN(CryptoPP)
-
-template <class T> const T& AbstractGroup<T>::Double(const Element &a) const
-{
- return this->Add(a, a);
-}
-
-template <class T> const T& AbstractGroup<T>::Subtract(const Element &a, const Element &b) const
-{
- // make copy of a in case Inverse() overwrites it
- Element a1(a);
- return this->Add(a1, Inverse(b));
-}
-
-template <class T> T& AbstractGroup<T>::Accumulate(Element &a, const Element &b) const
-{
- return a = this->Add(a, b);
-}
-
-template <class T> T& AbstractGroup<T>::Reduce(Element &a, const Element &b) const
-{
- return a = this->Subtract(a, b);
-}
-
-template <class T> const T& AbstractRing<T>::Square(const Element &a) const
-{
- return this->Multiply(a, a);
-}
-
-template <class T> const T& AbstractRing<T>::Divide(const Element &a, const Element &b) const
-{
- // make copy of a in case MultiplicativeInverse() overwrites it
- Element a1(a);
- return this->Multiply(a1, this->MultiplicativeInverse(b));
-}
-
-template <class T> const T& AbstractEuclideanDomain<T>::Mod(const Element &a, const Element &b) const
-{
- Element q;
- this->DivisionAlgorithm(result, q, a, b);
- return result;
-}
-
-template <class T> const T& AbstractEuclideanDomain<T>::Gcd(const Element &a, const Element &b) const
-{
- Element g[3]={b, a};
- unsigned int i0=0, i1=1, i2=2;
-
- while (!this->Equal(g[i1], this->Identity()))
- {
- g[i2] = this->Mod(g[i0], g[i1]);
- unsigned int t = i0; i0 = i1; i1 = i2; i2 = t;
- }
-
- return result = g[i0];
-}
-
-template <class T> const typename QuotientRing<T>::Element& QuotientRing<T>::MultiplicativeInverse(const Element &a) const
-{
- Element g[3]={m_modulus, a};
- Element v[3]={m_domain.Identity(), m_domain.MultiplicativeIdentity()};
- Element y;
- unsigned int i0=0, i1=1, i2=2;
-
- while (!this->Equal(g[i1], this->Identity()))
- {
- // y = g[i0] / g[i1];
- // g[i2] = g[i0] % g[i1];
- m_domain.DivisionAlgorithm(g[i2], y, g[i0], g[i1]);
- // v[i2] = v[i0] - (v[i1] * y);
- v[i2] = m_domain.Subtract(v[i0], m_domain.Multiply(v[i1], y));
- unsigned int t = i0; i0 = i1; i1 = i2; i2 = t;
- }
-
- return m_domain.IsUnit(g[i0]) ? m_domain.Divide(v[i0], g[i0]) : m_domain.Identity();
-}
-
-template <class T> T AbstractGroup<T>::ScalarMultiply(const Element &base, const Integer &exponent) const
-{
- Element result;
- this->SimultaneousMultiply(&result, base, &exponent, 1);
- return result;
-}
-
-template <class T> T AbstractGroup<T>::CascadeScalarMultiply(const Element &x, const Integer &e1, const Element &y, const Integer &e2) const
-{
- const unsigned expLen = STDMAX(e1.BitCount(), e2.BitCount());
- if (expLen==0)
- return this->Identity();
-
- const unsigned w = (expLen <= 46 ? 1 : (expLen <= 260 ? 2 : 3));
- const unsigned tableSize = 1<<w;
- std::vector<Element> powerTable(tableSize << w);
-
- powerTable[1] = x;
- powerTable[tableSize] = y;
- if (w==1)
- powerTable[3] = this->Add(x,y);
- else
- {
- powerTable[2] = this->Double(x);
- powerTable[2*tableSize] = this->Double(y);
-
- unsigned i, j;
-
- for (i=3; i<tableSize; i+=2)
- powerTable[i] = Add(powerTable[i-2], powerTable[2]);
- for (i=1; i<tableSize; i+=2)
- for (j=i+tableSize; j<(tableSize<<w); j+=tableSize)
- powerTable[j] = Add(powerTable[j-tableSize], y);
-
- for (i=3*tableSize; i<(tableSize<<w); i+=2*tableSize)
- powerTable[i] = Add(powerTable[i-2*tableSize], powerTable[2*tableSize]);
- for (i=tableSize; i<(tableSize<<w); i+=2*tableSize)
- for (j=i+2; j<i+tableSize; j+=2)
- powerTable[j] = Add(powerTable[j-1], x);
- }
-
- Element result;
- unsigned power1 = 0, power2 = 0, prevPosition = expLen-1;
- bool firstTime = true;
-
- for (int i = expLen-1; i>=0; i--)
- {
- power1 = 2*power1 + e1.GetBit(i);
- power2 = 2*power2 + e2.GetBit(i);
-
- if (i==0 || 2*power1 >= tableSize || 2*power2 >= tableSize)
- {
- unsigned squaresBefore = prevPosition-i;
- unsigned squaresAfter = 0;
- prevPosition = i;
- while ((power1 || power2) && power1%2 == 0 && power2%2==0)
- {
- power1 /= 2;
- power2 /= 2;
- squaresBefore--;
- squaresAfter++;
- }
- if (firstTime)
- {
- result = powerTable[(power2<<w) + power1];
- firstTime = false;
- }
- else
- {
- while (squaresBefore--)
- result = this->Double(result);
- if (power1 || power2)
- Accumulate(result, powerTable[(power2<<w) + power1]);
- }
- while (squaresAfter--)
- result = this->Double(result);
- power1 = power2 = 0;
- }
- }
- return result;
-}
-
-template <class Element, class Iterator> Element GeneralCascadeMultiplication(const AbstractGroup<Element> &group, Iterator begin, Iterator end)
-{
- if (end-begin == 1)
- return group.ScalarMultiply(begin->base, begin->exponent);
- else if (end-begin == 2)
- return group.CascadeScalarMultiply(begin->base, begin->exponent, (begin+1)->base, (begin+1)->exponent);
- else
- {
- Integer q, t;
- Iterator last = end;
- --last;
-
- std::make_heap(begin, end);
- std::pop_heap(begin, end);
-
- while (!!begin->exponent)
- {
- // last->exponent is largest exponent, begin->exponent is next largest
- t = last->exponent;
- Integer::Divide(last->exponent, q, t, begin->exponent);
-
- if (q == Integer::One())
- group.Accumulate(begin->base, last->base); // avoid overhead of ScalarMultiply()
- else
- group.Accumulate(begin->base, group.ScalarMultiply(last->base, q));
-
- std::push_heap(begin, end);
- std::pop_heap(begin, end);
- }
-
- return group.ScalarMultiply(last->base, last->exponent);
- }
-}
-
-struct WindowSlider
-{
- WindowSlider(const Integer &expIn, bool fastNegate, unsigned int windowSizeIn=0)
- : exp(expIn), windowModulus(Integer::One()), windowSize(windowSizeIn), windowBegin(0), fastNegate(fastNegate), firstTime(true), finished(false)
- {
- if (windowSize == 0)
- {
- unsigned int expLen = exp.BitCount();
- windowSize = expLen <= 17 ? 1 : (expLen <= 24 ? 2 : (expLen <= 70 ? 3 : (expLen <= 197 ? 4 : (expLen <= 539 ? 5 : (expLen <= 1434 ? 6 : 7)))));
- }
- windowModulus <<= windowSize;
- }
-
- void FindNextWindow()
- {
- unsigned int expLen = exp.WordCount() * WORD_BITS;
- unsigned int skipCount = firstTime ? 0 : windowSize;
- firstTime = false;
- while (!exp.GetBit(skipCount))
- {
- if (skipCount >= expLen)
- {
- finished = true;
- return;
- }
- skipCount++;
- }
-
- exp >>= skipCount;
- windowBegin += skipCount;
- expWindow = word32(exp % (word(1) << windowSize));
-
- if (fastNegate && exp.GetBit(windowSize))
- {
- negateNext = true;
- expWindow = (word32(1) << windowSize) - expWindow;
- exp += windowModulus;
- }
- else
- negateNext = false;
- }
-
- Integer exp, windowModulus;
- unsigned int windowSize, windowBegin;
- word32 expWindow;
- bool fastNegate, negateNext, firstTime, finished;
-};
-
-template <class T>
-void AbstractGroup<T>::SimultaneousMultiply(T *results, const T &base, const Integer *expBegin, unsigned int expCount) const
-{
- std::vector<std::vector<Element> > buckets(expCount);
- std::vector<WindowSlider> exponents;
- exponents.reserve(expCount);
- unsigned int i;
-
- for (i=0; i<expCount; i++)
- {
- assert(expBegin->NotNegative());
- exponents.push_back(WindowSlider(*expBegin++, InversionIsFast(), 0));
- exponents[i].FindNextWindow();
- buckets[i].resize(1<<(exponents[i].windowSize-1), Identity());
- }
-
- unsigned int expBitPosition = 0;
- Element g = base;
- bool notDone = true;
-
- while (notDone)
- {
- notDone = false;
- for (i=0; i<expCount; i++)
- {
- if (!exponents[i].finished && expBitPosition == exponents[i].windowBegin)
- {
- Element &bucket = buckets[i][exponents[i].expWindow/2];
- if (exponents[i].negateNext)
- Accumulate(bucket, Inverse(g));
- else
- Accumulate(bucket, g);
- exponents[i].FindNextWindow();
- }
- notDone = notDone || !exponents[i].finished;
- }
-
- if (notDone)
- {
- g = Double(g);
- expBitPosition++;
- }
- }
-
- for (i=0; i<expCount; i++)
- {
- Element &r = *results++;
- r = buckets[i][buckets[i].size()-1];
- if (buckets[i].size() > 1)
- {
- for (int j = (int)buckets[i].size()-2; j >= 1; j--)
- {
- Accumulate(buckets[i][j], buckets[i][j+1]);
- Accumulate(r, buckets[i][j]);
- }
- Accumulate(buckets[i][0], buckets[i][1]);
- r = Add(Double(r), buckets[i][0]);
- }
- }
-}
-
-template <class T> T AbstractRing<T>::Exponentiate(const Element &base, const Integer &exponent) const
-{
- Element result;
- SimultaneousExponentiate(&result, base, &exponent, 1);
- return result;
-}
-
-template <class T> T AbstractRing<T>::CascadeExponentiate(const Element &x, const Integer &e1, const Element &y, const Integer &e2) const
-{
- return MultiplicativeGroup().AbstractGroup<T>::CascadeScalarMultiply(x, e1, y, e2);
-}
-
-template <class Element, class Iterator> Element GeneralCascadeExponentiation(const AbstractRing<Element> &ring, Iterator begin, Iterator end)
-{
- return GeneralCascadeMultiplication<Element>(ring.MultiplicativeGroup(), begin, end);
-}
-
-template <class T>
-void AbstractRing<T>::SimultaneousExponentiate(T *results, const T &base, const Integer *exponents, unsigned int expCount) const
-{
- MultiplicativeGroup().AbstractGroup<T>::SimultaneousMultiply(results, base, exponents, expCount);
-}
-
-NAMESPACE_END
-
-#endif