what-the-bank/sources/org/bouncycastle/math/ec/custom/djb/Curve25519Field.java

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2024-07-27 18:17:47 +07:00
package org.bouncycastle.math.ec.custom.djb;
import java.math.BigInteger;
import org.bouncycastle.math.raw.Nat;
import org.bouncycastle.math.raw.Nat256;
/* loaded from: classes6.dex */
public class Curve25519Field {
private static final long M = 4294967295L;
private static final int P7 = Integer.MAX_VALUE;
private static final int PInv = 19;
static final int[] P = {-19, -1, -1, -1, -1, -1, -1, Integer.MAX_VALUE};
private static final int[] PExt = {361, 0, 0, 0, 0, 0, 0, 0, -19, -1, -1, -1, -1, -1, -1, 1073741823};
public static void twice(int[] iArr, int[] iArr2) {
Nat.shiftUpBit(8, iArr, 0, iArr2);
if (Nat256.gte(iArr2, P)) {
subPFrom(iArr2);
}
}
public static void subtractExt(int[] iArr, int[] iArr2, int[] iArr3) {
if (Nat.sub(16, iArr, iArr2, iArr3) != 0) {
addPExtTo(iArr3);
}
}
public static void subtract(int[] iArr, int[] iArr2, int[] iArr3) {
if (Nat256.sub(iArr, iArr2, iArr3) != 0) {
addPTo(iArr3);
}
}
private static int subPFrom(int[] iArr) {
long j = (iArr[0] & 4294967295L) + 19;
iArr[0] = (int) j;
long j2 = j >> 32;
if (j2 != 0) {
j2 = Nat.incAt(7, iArr, 1);
}
long j3 = j2 + ((4294967295L & iArr[7]) - 2147483648L);
iArr[7] = (int) j3;
return (int) (j3 >> 32);
}
private static int subPExtFrom(int[] iArr) {
long j = iArr[0];
int[] iArr2 = PExt;
long j2 = (j & 4294967295L) - (iArr2[0] & 4294967295L);
iArr[0] = (int) j2;
long j3 = j2 >> 32;
if (j3 != 0) {
j3 = Nat.decAt(8, iArr, 1);
}
long j4 = j3 + (iArr[8] & 4294967295L) + 19;
iArr[8] = (int) j4;
long j5 = j4 >> 32;
if (j5 != 0) {
j5 = Nat.incAt(15, iArr, 9);
}
long j6 = j5 + ((iArr[15] & 4294967295L) - ((iArr2[15] + 1) & 4294967295L));
iArr[15] = (int) j6;
return (int) (j6 >> 32);
}
public static void squareN(int[] iArr, int i, int[] iArr2) {
int[] createExt = Nat256.createExt();
Nat256.square(iArr, createExt);
while (true) {
reduce(createExt, iArr2);
i--;
if (i <= 0) {
return;
} else {
Nat256.square(iArr2, createExt);
}
}
}
public static void square(int[] iArr, int[] iArr2) {
int[] createExt = Nat256.createExt();
Nat256.square(iArr, createExt);
reduce(createExt, iArr2);
}
public static void reduce27(int i, int[] iArr) {
int i2 = iArr[7];
iArr[7] = (Integer.MAX_VALUE & i2) + Nat.addWordTo(7, ((i << 1) | (i2 >>> 31)) * 19, iArr);
if (Nat256.gte(iArr, P)) {
subPFrom(iArr);
}
}
public static void reduce(int[] iArr, int[] iArr2) {
int i = iArr[7];
Nat.shiftUpBit(8, iArr, 8, i, iArr2, 0);
int mulByWordAddTo = Nat256.mulByWordAddTo(19, iArr, iArr2);
int i2 = iArr2[7];
iArr2[7] = (Integer.MAX_VALUE & i2) + Nat.addWordTo(7, ((mulByWordAddTo << 1) + ((i2 >>> 31) - (i >>> 31))) * 19, iArr2);
if (Nat256.gte(iArr2, P)) {
subPFrom(iArr2);
}
}
public static void negate(int[] iArr, int[] iArr2) {
if (Nat256.isZero(iArr)) {
Nat256.zero(iArr2);
} else {
Nat256.sub(P, iArr, iArr2);
}
}
public static void multiplyAddToExt(int[] iArr, int[] iArr2, int[] iArr3) {
Nat256.mulAddTo(iArr, iArr2, iArr3);
if (Nat.gte(16, iArr3, PExt)) {
subPExtFrom(iArr3);
}
}
public static void multiply(int[] iArr, int[] iArr2, int[] iArr3) {
int[] createExt = Nat256.createExt();
Nat256.mul(iArr, iArr2, createExt);
reduce(createExt, iArr3);
}
public static void half(int[] iArr, int[] iArr2) {
if ((iArr[0] & 1) == 0) {
Nat.shiftDownBit(8, iArr, 0, iArr2);
} else {
Nat256.add(iArr, P, iArr2);
Nat.shiftDownBit(8, iArr2, 0);
}
}
public static int[] fromBigInteger(BigInteger bigInteger) {
int[] fromBigInteger = Nat256.fromBigInteger(bigInteger);
while (true) {
int[] iArr = P;
if (!Nat256.gte(fromBigInteger, iArr)) {
return fromBigInteger;
}
Nat256.subFrom(iArr, fromBigInteger);
}
}
private static int addPTo(int[] iArr) {
long j = (iArr[0] & 4294967295L) - 19;
iArr[0] = (int) j;
long j2 = j >> 32;
if (j2 != 0) {
j2 = Nat.decAt(7, iArr, 1);
}
long j3 = j2 + (4294967295L & iArr[7]) + 2147483648L;
iArr[7] = (int) j3;
return (int) (j3 >> 32);
}
private static int addPExtTo(int[] iArr) {
long j = iArr[0];
int[] iArr2 = PExt;
long j2 = (j & 4294967295L) + (iArr2[0] & 4294967295L);
iArr[0] = (int) j2;
long j3 = j2 >> 32;
if (j3 != 0) {
j3 = Nat.incAt(8, iArr, 1);
}
long j4 = j3 + ((iArr[8] & 4294967295L) - 19);
iArr[8] = (int) j4;
long j5 = j4 >> 32;
if (j5 != 0) {
j5 = Nat.decAt(15, iArr, 9);
}
long j6 = j5 + (iArr[15] & 4294967295L) + ((iArr2[15] + 1) & 4294967295L);
iArr[15] = (int) j6;
return (int) (j6 >> 32);
}
public static void addOne(int[] iArr, int[] iArr2) {
Nat.inc(8, iArr, iArr2);
if (Nat256.gte(iArr2, P)) {
subPFrom(iArr2);
}
}
public static void addExt(int[] iArr, int[] iArr2, int[] iArr3) {
Nat.add(16, iArr, iArr2, iArr3);
if (Nat.gte(16, iArr3, PExt)) {
subPExtFrom(iArr3);
}
}
public static void add(int[] iArr, int[] iArr2, int[] iArr3) {
Nat256.add(iArr, iArr2, iArr3);
if (Nat256.gte(iArr3, P)) {
subPFrom(iArr3);
}
}
}