what-the-bank/sources/org/bouncycastle/crypto/agreement/DHBasicAgreement.java

45 lines
2.0 KiB
Java

package org.bouncycastle.crypto.agreement;
import java.math.BigInteger;
import org.bouncycastle.crypto.BasicAgreement;
import org.bouncycastle.crypto.CipherParameters;
import org.bouncycastle.crypto.params.AsymmetricKeyParameter;
import org.bouncycastle.crypto.params.DHParameters;
import org.bouncycastle.crypto.params.DHPrivateKeyParameters;
import org.bouncycastle.crypto.params.DHPublicKeyParameters;
import org.bouncycastle.crypto.params.ParametersWithRandom;
/* loaded from: classes6.dex */
public class DHBasicAgreement implements BasicAgreement {
private DHParameters dhParams;
private DHPrivateKeyParameters key;
@Override // org.bouncycastle.crypto.BasicAgreement
public void init(CipherParameters cipherParameters) {
if (cipherParameters instanceof ParametersWithRandom) {
cipherParameters = ((ParametersWithRandom) cipherParameters).getParameters();
}
AsymmetricKeyParameter asymmetricKeyParameter = (AsymmetricKeyParameter) cipherParameters;
if (!(asymmetricKeyParameter instanceof DHPrivateKeyParameters)) {
throw new IllegalArgumentException("DHEngine expects DHPrivateKeyParameters");
}
DHPrivateKeyParameters dHPrivateKeyParameters = (DHPrivateKeyParameters) asymmetricKeyParameter;
this.key = dHPrivateKeyParameters;
this.dhParams = dHPrivateKeyParameters.getParameters();
}
@Override // org.bouncycastle.crypto.BasicAgreement
public int getFieldSize() {
return (this.key.getParameters().getP().bitLength() + 7) / 8;
}
@Override // org.bouncycastle.crypto.BasicAgreement
public BigInteger calculateAgreement(CipherParameters cipherParameters) {
DHPublicKeyParameters dHPublicKeyParameters = (DHPublicKeyParameters) cipherParameters;
if (dHPublicKeyParameters.getParameters().equals(this.dhParams)) {
return dHPublicKeyParameters.getY().modPow(this.key.getX(), this.dhParams.getP());
}
throw new IllegalArgumentException("Diffie-Hellman public key has wrong parameters.");
}
}