39 lines
1.4 KiB
Java
39 lines
1.4 KiB
Java
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package org.bouncycastle.math.field;
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import java.math.BigInteger;
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/* loaded from: classes6.dex */
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public abstract class FiniteFields {
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static final FiniteField GF_2 = new PrimeField(BigInteger.valueOf(2));
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static final FiniteField GF_3 = new PrimeField(BigInteger.valueOf(3));
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public static FiniteField getPrimeField(BigInteger bigInteger) {
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int bitLength = bigInteger.bitLength();
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if (bigInteger.signum() <= 0 || bitLength < 2) {
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throw new IllegalArgumentException("'characteristic' must be >= 2");
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}
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if (bitLength < 3) {
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int intValue = bigInteger.intValue();
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if (intValue == 2) {
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return GF_2;
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}
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if (intValue == 3) {
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return GF_3;
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}
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}
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return new PrimeField(bigInteger);
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}
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public static PolynomialExtensionField getBinaryExtensionField(int[] iArr) {
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if (iArr[0] != 0) {
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throw new IllegalArgumentException("Irreducible polynomials in GF(2) must have constant term");
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}
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for (int i = 1; i < iArr.length; i++) {
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if (iArr[i] <= iArr[i - 1]) {
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throw new IllegalArgumentException("Polynomial exponents must be montonically increasing");
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}
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}
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return new GenericPolynomialExtensionField(GF_2, new GF2Polynomial(iArr));
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}
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}
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