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-rw-r--r--bcprov/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/BigIntPolynomial.java394
1 files changed, 0 insertions, 394 deletions
diff --git a/bcprov/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/BigIntPolynomial.java b/bcprov/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/BigIntPolynomial.java
deleted file mode 100644
index 3c79b2e..0000000
--- a/bcprov/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/BigIntPolynomial.java
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@@ -1,394 +0,0 @@
-package org.bouncycastle.pqc.math.ntru.polynomial;
-
-import java.math.BigDecimal;
-import java.math.BigInteger;
-import java.security.SecureRandom;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-
-import org.bouncycastle.util.Arrays;
-
-/**
- * A polynomial with {@link BigInteger} coefficients.<br>
- * Some methods (like <code>add</code>) change the polynomial, others (like <code>mult</code>) do
- * not but return the result as a new polynomial.
- */
-public class BigIntPolynomial
-{
- private final static double LOG_10_2 = Math.log10(2);
-
- BigInteger[] coeffs;
-
- /**
- * Constructs a new polynomial with <code>N</code> coefficients initialized to 0.
- *
- * @param N the number of coefficients
- */
- BigIntPolynomial(int N)
- {
- coeffs = new BigInteger[N];
- for (int i = 0; i < N; i++)
- {
- coeffs[i] = Constants.BIGINT_ZERO;
- }
- }
-
- /**
- * Constructs a new polynomial with a given set of coefficients.
- *
- * @param coeffs the coefficients
- */
- BigIntPolynomial(BigInteger[] coeffs)
- {
- this.coeffs = coeffs;
- }
-
- /**
- * Constructs a <code>BigIntPolynomial</code> from a <code>IntegerPolynomial</code>. The two polynomials are
- * independent of each other.
- *
- * @param p the original polynomial
- */
- public BigIntPolynomial(IntegerPolynomial p)
- {
- coeffs = new BigInteger[p.coeffs.length];
- for (int i = 0; i < coeffs.length; i++)
- {
- coeffs[i] = BigInteger.valueOf(p.coeffs[i]);
- }
- }
-
- /**
- * Generates a random polynomial with <code>numOnes</code> coefficients equal to 1,
- * <code>numNegOnes</code> coefficients equal to -1, and the rest equal to 0.
- *
- * @param N number of coefficients
- * @param numOnes number of 1's
- * @param numNegOnes number of -1's
- * @return
- */
- static BigIntPolynomial generateRandomSmall(int N, int numOnes, int numNegOnes)
- {
- List coeffs = new ArrayList();
- for (int i = 0; i < numOnes; i++)
- {
- coeffs.add(Constants.BIGINT_ONE);
- }
- for (int i = 0; i < numNegOnes; i++)
- {
- coeffs.add(BigInteger.valueOf(-1));
- }
- while (coeffs.size() < N)
- {
- coeffs.add(Constants.BIGINT_ZERO);
- }
- Collections.shuffle(coeffs, new SecureRandom());
-
- BigIntPolynomial poly = new BigIntPolynomial(N);
- for (int i = 0; i < coeffs.size(); i++)
- {
- poly.coeffs[i] = (BigInteger)coeffs.get(i);
- }
- return poly;
- }
-
- /**
- * Multiplies the polynomial by another, taking the indices mod N. Does not
- * change this polynomial but returns the result as a new polynomial.<br>
- * Both polynomials must have the same number of coefficients.
- *
- * @param poly2 the polynomial to multiply by
- * @return a new polynomial
- */
- public BigIntPolynomial mult(BigIntPolynomial poly2)
- {
- int N = coeffs.length;
- if (poly2.coeffs.length != N)
- {
- throw new IllegalArgumentException("Number of coefficients must be the same");
- }
-
- BigIntPolynomial c = multRecursive(poly2);
-
- if (c.coeffs.length > N)
- {
- for (int k = N; k < c.coeffs.length; k++)
- {
- c.coeffs[k - N] = c.coeffs[k - N].add(c.coeffs[k]);
- }
- c.coeffs = Arrays.copyOf(c.coeffs, N);
- }
- return c;
- }
-
- /**
- * Karazuba multiplication
- */
- private BigIntPolynomial multRecursive(BigIntPolynomial poly2)
- {
- BigInteger[] a = coeffs;
- BigInteger[] b = poly2.coeffs;
-
- int n = poly2.coeffs.length;
- if (n <= 1)
- {
- BigInteger[] c = Arrays.clone(coeffs);
- for (int i = 0; i < coeffs.length; i++)
- {
- c[i] = c[i].multiply(poly2.coeffs[0]);
- }
- return new BigIntPolynomial(c);
- }
- else
- {
- int n1 = n / 2;
-
- BigIntPolynomial a1 = new BigIntPolynomial(Arrays.copyOf(a, n1));
- BigIntPolynomial a2 = new BigIntPolynomial(Arrays.copyOfRange(a, n1, n));
- BigIntPolynomial b1 = new BigIntPolynomial(Arrays.copyOf(b, n1));
- BigIntPolynomial b2 = new BigIntPolynomial(Arrays.copyOfRange(b, n1, n));
-
- BigIntPolynomial A = (BigIntPolynomial)a1.clone();
- A.add(a2);
- BigIntPolynomial B = (BigIntPolynomial)b1.clone();
- B.add(b2);
-
- BigIntPolynomial c1 = a1.multRecursive(b1);
- BigIntPolynomial c2 = a2.multRecursive(b2);
- BigIntPolynomial c3 = A.multRecursive(B);
- c3.sub(c1);
- c3.sub(c2);
-
- BigIntPolynomial c = new BigIntPolynomial(2 * n - 1);
- for (int i = 0; i < c1.coeffs.length; i++)
- {
- c.coeffs[i] = c1.coeffs[i];
- }
- for (int i = 0; i < c3.coeffs.length; i++)
- {
- c.coeffs[n1 + i] = c.coeffs[n1 + i].add(c3.coeffs[i]);
- }
- for (int i = 0; i < c2.coeffs.length; i++)
- {
- c.coeffs[2 * n1 + i] = c.coeffs[2 * n1 + i].add(c2.coeffs[i]);
- }
- return c;
- }
- }
-
- /**
- * Adds another polynomial which can have a different number of coefficients,
- * and takes the coefficient values mod <code>modulus</code>.
- *
- * @param b another polynomial
- */
- void add(BigIntPolynomial b, BigInteger modulus)
- {
- add(b);
- mod(modulus);
- }
-
- /**
- * Adds another polynomial which can have a different number of coefficients.
- *
- * @param b another polynomial
- */
- public void add(BigIntPolynomial b)
- {
- if (b.coeffs.length > coeffs.length)
- {
- int N = coeffs.length;
- coeffs = Arrays.copyOf(coeffs, b.coeffs.length);
- for (int i = N; i < coeffs.length; i++)
- {
- coeffs[i] = Constants.BIGINT_ZERO;
- }
- }
- for (int i = 0; i < b.coeffs.length; i++)
- {
- coeffs[i] = coeffs[i].add(b.coeffs[i]);
- }
- }
-
- /**
- * Subtracts another polynomial which can have a different number of coefficients.
- *
- * @param b another polynomial
- */
- public void sub(BigIntPolynomial b)
- {
- if (b.coeffs.length > coeffs.length)
- {
- int N = coeffs.length;
- coeffs = Arrays.copyOf(coeffs, b.coeffs.length);
- for (int i = N; i < coeffs.length; i++)
- {
- coeffs[i] = Constants.BIGINT_ZERO;
- }
- }
- for (int i = 0; i < b.coeffs.length; i++)
- {
- coeffs[i] = coeffs[i].subtract(b.coeffs[i]);
- }
- }
-
- /**
- * Multiplies each coefficient by a <code>BigInteger</code>. Does not return a new polynomial but modifies this polynomial.
- *
- * @param factor
- */
- public void mult(BigInteger factor)
- {
- for (int i = 0; i < coeffs.length; i++)
- {
- coeffs[i] = coeffs[i].multiply(factor);
- }
- }
-
- /**
- * Multiplies each coefficient by a <code>int</code>. Does not return a new polynomial but modifies this polynomial.
- *
- * @param factor
- */
- void mult(int factor)
- {
- mult(BigInteger.valueOf(factor));
- }
-
- /**
- * Divides each coefficient by a <code>BigInteger</code> and rounds the result to the nearest whole number.<br>
- * Does not return a new polynomial but modifies this polynomial.
- *
- * @param divisor the number to divide by
- */
- public void div(BigInteger divisor)
- {
- BigInteger d = divisor.add(Constants.BIGINT_ONE).divide(BigInteger.valueOf(2));
- for (int i = 0; i < coeffs.length; i++)
- {
- coeffs[i] = coeffs[i].compareTo(Constants.BIGINT_ZERO) > 0 ? coeffs[i].add(d) : coeffs[i].add(d.negate());
- coeffs[i] = coeffs[i].divide(divisor);
- }
- }
-
- /**
- * Divides each coefficient by a <code>BigDecimal</code> and rounds the result to <code>decimalPlaces</code> places.
- *
- * @param divisor the number to divide by
- * @param decimalPlaces the number of fractional digits to round the result to
- * @return a new <code>BigDecimalPolynomial</code>
- */
- public BigDecimalPolynomial div(BigDecimal divisor, int decimalPlaces)
- {
- BigInteger max = maxCoeffAbs();
- int coeffLength = (int)(max.bitLength() * LOG_10_2) + 1;
- // factor = 1/divisor
- BigDecimal factor = Constants.BIGDEC_ONE.divide(divisor, coeffLength + decimalPlaces + 1, BigDecimal.ROUND_HALF_EVEN);
-
- // multiply each coefficient by factor
- BigDecimalPolynomial p = new BigDecimalPolynomial(coeffs.length);
- for (int i = 0; i < coeffs.length; i++)
- // multiply, then truncate after decimalPlaces so subsequent operations aren't slowed down
- {
- p.coeffs[i] = new BigDecimal(coeffs[i]).multiply(factor).setScale(decimalPlaces, BigDecimal.ROUND_HALF_EVEN);
- }
-
- return p;
- }
-
- /**
- * Returns the base10 length of the largest coefficient.
- *
- * @return length of the longest coefficient
- */
- public int getMaxCoeffLength()
- {
- return (int)(maxCoeffAbs().bitLength() * LOG_10_2) + 1;
- }
-
- private BigInteger maxCoeffAbs()
- {
- BigInteger max = coeffs[0].abs();
- for (int i = 1; i < coeffs.length; i++)
- {
- BigInteger coeff = coeffs[i].abs();
- if (coeff.compareTo(max) > 0)
- {
- max = coeff;
- }
- }
- return max;
- }
-
- /**
- * Takes each coefficient modulo a number.
- *
- * @param modulus
- */
- public void mod(BigInteger modulus)
- {
- for (int i = 0; i < coeffs.length; i++)
- {
- coeffs[i] = coeffs[i].mod(modulus);
- }
- }
-
- /**
- * Returns the sum of all coefficients, i.e. evaluates the polynomial at 0.
- *
- * @return the sum of all coefficients
- */
- BigInteger sumCoeffs()
- {
- BigInteger sum = Constants.BIGINT_ZERO;
- for (int i = 0; i < coeffs.length; i++)
- {
- sum = sum.add(coeffs[i]);
- }
- return sum;
- }
-
- /**
- * Makes a copy of the polynomial that is independent of the original.
- */
- public Object clone()
- {
- return new BigIntPolynomial(coeffs.clone());
- }
-
- public int hashCode()
- {
- final int prime = 31;
- int result = 1;
- result = prime * result + Arrays.hashCode(coeffs);
- return result;
- }
-
- public boolean equals(Object obj)
- {
- if (this == obj)
- {
- return true;
- }
- if (obj == null)
- {
- return false;
- }
- if (getClass() != obj.getClass())
- {
- return false;
- }
- BigIntPolynomial other = (BigIntPolynomial)obj;
- if (!Arrays.areEqual(coeffs, other.coeffs))
- {
- return false;
- }
- return true;
- }
-
- public BigInteger[] getCoeffs()
- {
- return Arrays.clone(coeffs);
- }
-}