35 lines
1.3 KiB
Java
35 lines
1.3 KiB
Java
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package org.bouncycastle.math.ec;
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import java.math.BigInteger;
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/* loaded from: classes6.dex */
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public class FixedPointCombMultiplier extends AbstractECMultiplier {
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protected int getWidthForCombSize(int i) {
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return i > 257 ? 6 : 5;
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}
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@Override // org.bouncycastle.math.ec.AbstractECMultiplier
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protected ECPoint multiplyPositive(ECPoint eCPoint, BigInteger bigInteger) {
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ECCurve curve = eCPoint.getCurve();
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int combSize = FixedPointUtil.getCombSize(curve);
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if (bigInteger.bitLength() > combSize) {
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throw new IllegalStateException("fixed-point comb doesn't support scalars larger than the curve order");
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}
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FixedPointPreCompInfo precompute = FixedPointUtil.precompute(eCPoint, getWidthForCombSize(combSize));
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ECPoint[] preComp = precompute.getPreComp();
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int width = ((combSize + r9) - 1) / precompute.getWidth();
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ECPoint infinity = curve.getInfinity();
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for (int i = 0; i < width; i++) {
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int i2 = 0;
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for (int i3 = ((r9 * width) - 1) - i; i3 >= 0; i3 -= width) {
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i2 <<= 1;
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if (bigInteger.testBit(i3)) {
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i2 |= 1;
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}
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}
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infinity = infinity.twicePlus(preComp[i2]);
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}
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return infinity;
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}
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}
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