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-rw-r--r--bcprov/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/SparseTernaryPolynomial.java320
1 files changed, 0 insertions, 320 deletions
diff --git a/bcprov/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/SparseTernaryPolynomial.java b/bcprov/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/SparseTernaryPolynomial.java
deleted file mode 100644
index 3c91339..0000000
--- a/bcprov/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/SparseTernaryPolynomial.java
+++ /dev/null
@@ -1,320 +0,0 @@
-package org.bouncycastle.pqc.math.ntru.polynomial;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.math.BigInteger;
-import java.security.SecureRandom;
-
-import org.bouncycastle.pqc.math.ntru.util.ArrayEncoder;
-import org.bouncycastle.pqc.math.ntru.util.Util;
-import org.bouncycastle.util.Arrays;
-
-/**
- * A <code>TernaryPolynomial</code> with a "low" number of nonzero coefficients.
- */
-public class SparseTernaryPolynomial
- implements TernaryPolynomial
-{
- /**
- * Number of bits to use for each coefficient. Determines the upper bound for <code>N</code>.
- */
- private static final int BITS_PER_INDEX = 11;
-
- private int N;
- private int[] ones;
- private int[] negOnes;
-
- /**
- * Constructs a new polynomial.
- *
- * @param N total number of coefficients including zeros
- * @param ones indices of coefficients equal to 1
- * @param negOnes indices of coefficients equal to -1
- */
- SparseTernaryPolynomial(int N, int[] ones, int[] negOnes)
- {
- this.N = N;
- this.ones = ones;
- this.negOnes = negOnes;
- }
-
- /**
- * Constructs a <code>DenseTernaryPolynomial</code> from a <code>IntegerPolynomial</code>. The two polynomials are
- * independent of each other.
- *
- * @param intPoly the original polynomial
- */
- public SparseTernaryPolynomial(IntegerPolynomial intPoly)
- {
- this(intPoly.coeffs);
- }
-
- /**
- * Constructs a new <code>SparseTernaryPolynomial</code> with a given set of coefficients.
- *
- * @param coeffs the coefficients
- */
- public SparseTernaryPolynomial(int[] coeffs)
- {
- N = coeffs.length;
- ones = new int[N];
- negOnes = new int[N];
- int onesIdx = 0;
- int negOnesIdx = 0;
- for (int i = 0; i < N; i++)
- {
- int c = coeffs[i];
- switch (c)
- {
- case 1:
- ones[onesIdx++] = i;
- break;
- case -1:
- negOnes[negOnesIdx++] = i;
- break;
- case 0:
- break;
- default:
- throw new IllegalArgumentException("Illegal value: " + c + ", must be one of {-1, 0, 1}");
- }
- }
- ones = Arrays.copyOf(ones, onesIdx);
- negOnes = Arrays.copyOf(negOnes, negOnesIdx);
- }
-
- /**
- * Decodes a byte array encoded with {@link #toBinary()} to a ploynomial.
- *
- * @param is an input stream containing an encoded polynomial
- * @param N number of coefficients including zeros
- * @param numOnes number of coefficients equal to 1
- * @param numNegOnes number of coefficients equal to -1
- * @return the decoded polynomial
- * @throws IOException
- */
- public static SparseTernaryPolynomial fromBinary(InputStream is, int N, int numOnes, int numNegOnes)
- throws IOException
- {
- int maxIndex = 1 << BITS_PER_INDEX;
- int bitsPerIndex = 32 - Integer.numberOfLeadingZeros(maxIndex - 1);
-
- int data1Len = (numOnes * bitsPerIndex + 7) / 8;
- byte[] data1 = Util.readFullLength(is, data1Len);
- int[] ones = ArrayEncoder.decodeModQ(data1, numOnes, maxIndex);
-
- int data2Len = (numNegOnes * bitsPerIndex + 7) / 8;
- byte[] data2 = Util.readFullLength(is, data2Len);
- int[] negOnes = ArrayEncoder.decodeModQ(data2, numNegOnes, maxIndex);
-
- return new SparseTernaryPolynomial(N, ones, negOnes);
- }
-
- /**
- * 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
- */
- public static SparseTernaryPolynomial generateRandom(int N, int numOnes, int numNegOnes, SecureRandom random)
- {
- int[] coeffs = Util.generateRandomTernary(N, numOnes, numNegOnes, random);
- return new SparseTernaryPolynomial(coeffs);
- }
-
- public IntegerPolynomial mult(IntegerPolynomial poly2)
- {
- int[] b = poly2.coeffs;
- if (b.length != N)
- {
- throw new IllegalArgumentException("Number of coefficients must be the same");
- }
-
- int[] c = new int[N];
- for (int idx = 0; idx != ones.length; idx++)
- {
- int i = ones[idx];
- int j = N - 1 - i;
- for (int k = N - 1; k >= 0; k--)
- {
- c[k] += b[j];
- j--;
- if (j < 0)
- {
- j = N - 1;
- }
- }
- }
-
- for (int idx = 0; idx != negOnes.length; idx++)
- {
- int i = negOnes[idx];
- int j = N - 1 - i;
- for (int k = N - 1; k >= 0; k--)
- {
- c[k] -= b[j];
- j--;
- if (j < 0)
- {
- j = N - 1;
- }
- }
- }
-
- return new IntegerPolynomial(c);
- }
-
- public IntegerPolynomial mult(IntegerPolynomial poly2, int modulus)
- {
- IntegerPolynomial c = mult(poly2);
- c.mod(modulus);
- return c;
- }
-
- public BigIntPolynomial mult(BigIntPolynomial poly2)
- {
- BigInteger[] b = poly2.coeffs;
- if (b.length != N)
- {
- throw new IllegalArgumentException("Number of coefficients must be the same");
- }
-
- BigInteger[] c = new BigInteger[N];
- for (int i = 0; i < N; i++)
- {
- c[i] = BigInteger.ZERO;
- }
-
- for (int idx = 0; idx != ones.length; idx++)
- {
- int i = ones[idx];
- int j = N - 1 - i;
- for (int k = N - 1; k >= 0; k--)
- {
- c[k] = c[k].add(b[j]);
- j--;
- if (j < 0)
- {
- j = N - 1;
- }
- }
- }
-
- for (int idx = 0; idx != negOnes.length; idx++)
- {
- int i = negOnes[idx];
- int j = N - 1 - i;
- for (int k = N - 1; k >= 0; k--)
- {
- c[k] = c[k].subtract(b[j]);
- j--;
- if (j < 0)
- {
- j = N - 1;
- }
- }
- }
-
- return new BigIntPolynomial(c);
- }
-
- public int[] getOnes()
- {
- return ones;
- }
-
- public int[] getNegOnes()
- {
- return negOnes;
- }
-
- /**
- * Encodes the polynomial to a byte array writing <code>BITS_PER_INDEX</code> bits for each coefficient.
- *
- * @return the encoded polynomial
- */
- public byte[] toBinary()
- {
- int maxIndex = 1 << BITS_PER_INDEX;
- byte[] bin1 = ArrayEncoder.encodeModQ(ones, maxIndex);
- byte[] bin2 = ArrayEncoder.encodeModQ(negOnes, maxIndex);
-
- byte[] bin = Arrays.copyOf(bin1, bin1.length + bin2.length);
- System.arraycopy(bin2, 0, bin, bin1.length, bin2.length);
- return bin;
- }
-
- public IntegerPolynomial toIntegerPolynomial()
- {
- int[] coeffs = new int[N];
- for (int idx = 0; idx != ones.length; idx++)
- {
- int i = ones[idx];
- coeffs[i] = 1;
- }
- for (int idx = 0; idx != negOnes.length; idx++)
- {
- int i = negOnes[idx];
- coeffs[i] = -1;
- }
- return new IntegerPolynomial(coeffs);
- }
-
- public int size()
- {
- return N;
- }
-
- public void clear()
- {
- for (int i = 0; i < ones.length; i++)
- {
- ones[i] = 0;
- }
- for (int i = 0; i < negOnes.length; i++)
- {
- negOnes[i] = 0;
- }
- }
-
- public int hashCode()
- {
- final int prime = 31;
- int result = 1;
- result = prime * result + N;
- result = prime * result + Arrays.hashCode(negOnes);
- result = prime * result + Arrays.hashCode(ones);
- return result;
- }
-
- public boolean equals(Object obj)
- {
- if (this == obj)
- {
- return true;
- }
- if (obj == null)
- {
- return false;
- }
- if (getClass() != obj.getClass())
- {
- return false;
- }
- SparseTernaryPolynomial other = (SparseTernaryPolynomial)obj;
- if (N != other.N)
- {
- return false;
- }
- if (!Arrays.areEqual(negOnes, other.negOnes))
- {
- return false;
- }
- if (!Arrays.areEqual(ones, other.ones))
- {
- return false;
- }
- return true;
- }
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-18 16:34:55 +0000