diff options
Diffstat (limited to 'core/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/LongPolynomial2.java')
| -rw-r--r-- | core/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/LongPolynomial2.java | 255 |
1 files changed, 0 insertions, 255 deletions
diff --git a/core/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/LongPolynomial2.java b/core/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/LongPolynomial2.java deleted file mode 100644 index d71615a3..00000000 --- a/core/src/main/java/org/bouncycastle/pqc/math/ntru/polynomial/LongPolynomial2.java +++ /dev/null @@ -1,255 +0,0 @@ -package org.bouncycastle.pqc.math.ntru.polynomial; - -import org.bouncycastle.util.Arrays; - -/** - * A polynomial class that combines two coefficients into one <code>long</code> value for - * faster multiplication in 64 bit environments.<br> - * Coefficients can be between 0 and 2047 and are stored in pairs in the bits 0..10 and 24..34 of a <code>long</code> number. - */ -public class LongPolynomial2 -{ - private long[] coeffs; // each representing two coefficients in the original IntegerPolynomial - private int numCoeffs; - - /** - * Constructs a <code>LongPolynomial2</code> from a <code>IntegerPolynomial</code>. The two polynomials are independent of each other. - * - * @param p the original polynomial. Coefficients must be between 0 and 2047. - */ - public LongPolynomial2(IntegerPolynomial p) - { - numCoeffs = p.coeffs.length; - coeffs = new long[(numCoeffs + 1) / 2]; - int idx = 0; - for (int pIdx = 0; pIdx < numCoeffs; ) - { - int c0 = p.coeffs[pIdx++]; - while (c0 < 0) - { - c0 += 2048; - } - long c1 = pIdx < numCoeffs ? p.coeffs[pIdx++] : 0; - while (c1 < 0) - { - c1 += 2048; - } - coeffs[idx] = c0 + (c1 << 24); - idx++; - } - } - - private LongPolynomial2(long[] coeffs) - { - this.coeffs = coeffs; - } - - private LongPolynomial2(int N) - { - coeffs = new long[N]; - } - - /** - * Multiplies the polynomial with another, taking the indices mod N and the values mod 2048. - */ - public LongPolynomial2 mult(LongPolynomial2 poly2) - { - int N = coeffs.length; - if (poly2.coeffs.length != N || numCoeffs != poly2.numCoeffs) - { - throw new IllegalArgumentException("Number of coefficients must be the same"); - } - - LongPolynomial2 c = multRecursive(poly2); - - if (c.coeffs.length > N) - { - if (numCoeffs % 2 == 0) - { - for (int k = N; k < c.coeffs.length; k++) - { - c.coeffs[k - N] = (c.coeffs[k - N] + c.coeffs[k]) & 0x7FF0007FFL; - } - c.coeffs = Arrays.copyOf(c.coeffs, N); - } - else - { - for (int k = N; k < c.coeffs.length; k++) - { - c.coeffs[k - N] = c.coeffs[k - N] + (c.coeffs[k - 1] >> 24); - c.coeffs[k - N] = c.coeffs[k - N] + ((c.coeffs[k] & 2047) << 24); - c.coeffs[k - N] &= 0x7FF0007FFL; - } - c.coeffs = Arrays.copyOf(c.coeffs, N); - c.coeffs[c.coeffs.length - 1] &= 2047; - } - } - - c = new LongPolynomial2(c.coeffs); - c.numCoeffs = numCoeffs; - return c; - } - - public IntegerPolynomial toIntegerPolynomial() - { - int[] intCoeffs = new int[numCoeffs]; - int uIdx = 0; - for (int i = 0; i < coeffs.length; i++) - { - intCoeffs[uIdx++] = (int)(coeffs[i] & 2047); - if (uIdx < numCoeffs) - { - intCoeffs[uIdx++] = (int)((coeffs[i] >> 24) & 2047); - } - } - return new IntegerPolynomial(intCoeffs); - } - - /** - * Karazuba multiplication - */ - private LongPolynomial2 multRecursive(LongPolynomial2 poly2) - { - long[] a = coeffs; - long[] b = poly2.coeffs; - - int n = poly2.coeffs.length; - if (n <= 32) - { - int cn = 2 * n; - LongPolynomial2 c = new LongPolynomial2(new long[cn]); - for (int k = 0; k < cn; k++) - { - for (int i = Math.max(0, k - n + 1); i <= Math.min(k, n - 1); i++) - { - long c0 = a[k - i] * b[i]; - long cu = c0 & 0x7FF000000L + (c0 & 2047); - long co = (c0 >>> 48) & 2047; - - c.coeffs[k] = (c.coeffs[k] + cu) & 0x7FF0007FFL; - c.coeffs[k + 1] = (c.coeffs[k + 1] + co) & 0x7FF0007FFL; - } - } - return c; - } - else - { - int n1 = n / 2; - - LongPolynomial2 a1 = new LongPolynomial2(Arrays.copyOf(a, n1)); - LongPolynomial2 a2 = new LongPolynomial2(Arrays.copyOfRange(a, n1, n)); - LongPolynomial2 b1 = new LongPolynomial2(Arrays.copyOf(b, n1)); - LongPolynomial2 b2 = new LongPolynomial2(Arrays.copyOfRange(b, n1, n)); - - LongPolynomial2 A = (LongPolynomial2)a1.clone(); - A.add(a2); - LongPolynomial2 B = (LongPolynomial2)b1.clone(); - B.add(b2); - - LongPolynomial2 c1 = a1.multRecursive(b1); - LongPolynomial2 c2 = a2.multRecursive(b2); - LongPolynomial2 c3 = A.multRecursive(B); - c3.sub(c1); - c3.sub(c2); - - LongPolynomial2 c = new LongPolynomial2(2 * n); - for (int i = 0; i < c1.coeffs.length; i++) - { - c.coeffs[i] = c1.coeffs[i] & 0x7FF0007FFL; - } - for (int i = 0; i < c3.coeffs.length; i++) - { - c.coeffs[n1 + i] = (c.coeffs[n1 + i] + c3.coeffs[i]) & 0x7FF0007FFL; - } - for (int i = 0; i < c2.coeffs.length; i++) - { - c.coeffs[2 * n1 + i] = (c.coeffs[2 * n1 + i] + c2.coeffs[i]) & 0x7FF0007FFL; - } - return c; - } - } - - /** - * Adds another polynomial which can have a different number of coefficients. - * - * @param b another polynomial - */ - private void add(LongPolynomial2 b) - { - if (b.coeffs.length > coeffs.length) - { - coeffs = Arrays.copyOf(coeffs, b.coeffs.length); - } - for (int i = 0; i < b.coeffs.length; i++) - { - coeffs[i] = (coeffs[i] + b.coeffs[i]) & 0x7FF0007FFL; - } - } - - /** - * Subtracts another polynomial which can have a different number of coefficients. - * - * @param b another polynomial - */ - private void sub(LongPolynomial2 b) - { - if (b.coeffs.length > coeffs.length) - { - coeffs = Arrays.copyOf(coeffs, b.coeffs.length); - } - for (int i = 0; i < b.coeffs.length; i++) - { - coeffs[i] = (0x0800000800000L + coeffs[i] - b.coeffs[i]) & 0x7FF0007FFL; - } - } - - /** - * Subtracts another polynomial which must have the same number of coefficients, - * and applies an AND mask to the upper and lower halves of each coefficients. - * - * @param b another polynomial - * @param mask a bit mask less than 2048 to apply to each 11-bit coefficient - */ - public void subAnd(LongPolynomial2 b, int mask) - { - long longMask = (((long)mask) << 24) + mask; - for (int i = 0; i < b.coeffs.length; i++) - { - coeffs[i] = (0x0800000800000L + coeffs[i] - b.coeffs[i]) & longMask; - } - } - - /** - * Multiplies this polynomial by 2 and applies an AND mask to the upper and - * lower halves of each coefficients. - * - * @param mask a bit mask less than 2048 to apply to each 11-bit coefficient - */ - public void mult2And(int mask) - { - long longMask = (((long)mask) << 24) + mask; - for (int i = 0; i < coeffs.length; i++) - { - coeffs[i] = (coeffs[i] << 1) & longMask; - } - } - - public Object clone() - { - LongPolynomial2 p = new LongPolynomial2(coeffs.clone()); - p.numCoeffs = numCoeffs; - return p; - } - - public boolean equals(Object obj) - { - if (obj instanceof LongPolynomial2) - { - return Arrays.areEqual(coeffs, ((LongPolynomial2)obj).coeffs); - } - else - { - return false; - } - } -} |