73 lines
2.9 KiB
Java
73 lines
2.9 KiB
Java
package org.bouncycastle.crypto.generators;
|
|
|
|
import java.math.BigInteger;
|
|
import java.security.SecureRandom;
|
|
import org.bouncycastle.crypto.digests.SHA256Digest;
|
|
import org.bouncycastle.crypto.params.CramerShoupParameters;
|
|
import org.bouncycastle.crypto.params.DHParameters;
|
|
import org.bouncycastle.util.BigIntegers;
|
|
|
|
/* loaded from: classes6.dex */
|
|
public class CramerShoupParametersGenerator {
|
|
private static final BigInteger ONE = BigInteger.valueOf(1);
|
|
private int certainty;
|
|
private SecureRandom random;
|
|
private int size;
|
|
|
|
public void init(int i, int i2, SecureRandom secureRandom) {
|
|
this.size = i;
|
|
this.certainty = i2;
|
|
this.random = secureRandom;
|
|
}
|
|
|
|
/* loaded from: classes6.dex */
|
|
static class ParametersHelper {
|
|
private static final BigInteger TWO = BigInteger.valueOf(2);
|
|
|
|
static BigInteger selectGenerator(BigInteger bigInteger, SecureRandom secureRandom) {
|
|
BigInteger modPow;
|
|
BigInteger subtract = bigInteger.subtract(TWO);
|
|
do {
|
|
BigInteger bigInteger2 = TWO;
|
|
modPow = BigIntegers.createRandomInRange(bigInteger2, subtract, secureRandom).modPow(bigInteger2, bigInteger);
|
|
} while (modPow.equals(CramerShoupParametersGenerator.ONE));
|
|
return modPow;
|
|
}
|
|
|
|
static BigInteger[] generateSafePrimes(int i, int i2, SecureRandom secureRandom) {
|
|
BigInteger bigInteger;
|
|
BigInteger add;
|
|
while (true) {
|
|
bigInteger = new BigInteger(i - 1, 2, secureRandom);
|
|
add = bigInteger.shiftLeft(1).add(CramerShoupParametersGenerator.ONE);
|
|
if (!add.isProbablePrime(i2) || (i2 > 2 && !bigInteger.isProbablePrime(i2))) {
|
|
}
|
|
}
|
|
return new BigInteger[]{add, bigInteger};
|
|
}
|
|
|
|
private ParametersHelper() {
|
|
}
|
|
}
|
|
|
|
public CramerShoupParameters generateParameters(DHParameters dHParameters) {
|
|
BigInteger selectGenerator;
|
|
BigInteger p = dHParameters.getP();
|
|
BigInteger g = dHParameters.getG();
|
|
do {
|
|
selectGenerator = ParametersHelper.selectGenerator(p, this.random);
|
|
} while (g.equals(selectGenerator));
|
|
return new CramerShoupParameters(p, g, selectGenerator, new SHA256Digest());
|
|
}
|
|
|
|
public CramerShoupParameters generateParameters() {
|
|
BigInteger selectGenerator;
|
|
BigInteger bigInteger = ParametersHelper.generateSafePrimes(this.size, this.certainty, this.random)[1];
|
|
BigInteger selectGenerator2 = ParametersHelper.selectGenerator(bigInteger, this.random);
|
|
do {
|
|
selectGenerator = ParametersHelper.selectGenerator(bigInteger, this.random);
|
|
} while (selectGenerator2.equals(selectGenerator));
|
|
return new CramerShoupParameters(bigInteger, selectGenerator2, selectGenerator, new SHA256Digest());
|
|
}
|
|
}
|