55 lines
2.5 KiB
Java
55 lines
2.5 KiB
Java
|
package org.bouncycastle.crypto.ec;
|
||
|
|
|
||
|
|
import java.math.BigInteger;
|
||
|
|
import java.security.SecureRandom;
|
||
|
|
import org.bouncycastle.crypto.CipherParameters;
|
||
|
|
import org.bouncycastle.crypto.params.ECDomainParameters;
|
||
|
|
import org.bouncycastle.crypto.params.ECPublicKeyParameters;
|
||
|
|
import org.bouncycastle.crypto.params.ParametersWithRandom;
|
||
|
|
import org.bouncycastle.math.ec.ECMultiplier;
|
||
|
|
import org.bouncycastle.math.ec.ECPoint;
|
||
|
|
import org.bouncycastle.math.ec.FixedPointCombMultiplier;
|
||
|
|
|
||
|
|
/* loaded from: classes6.dex */
|
||
|
|
public class ECElGamalEncryptor implements ECEncryptor {
|
||
|
|
private ECPublicKeyParameters key;
|
||
|
|
private SecureRandom random;
|
||
|
|
|
||
|
|
@Override // org.bouncycastle.crypto.ec.ECEncryptor
|
||
|
|
public void init(CipherParameters cipherParameters) {
|
||
|
|
SecureRandom secureRandom;
|
||
|
|
if (cipherParameters instanceof ParametersWithRandom) {
|
||
|
|
ParametersWithRandom parametersWithRandom = (ParametersWithRandom) cipherParameters;
|
||
|
|
if (!(parametersWithRandom.getParameters() instanceof ECPublicKeyParameters)) {
|
||
|
|
throw new IllegalArgumentException("ECPublicKeyParameters are required for encryption.");
|
||
|
|
}
|
||
|
|
this.key = (ECPublicKeyParameters) parametersWithRandom.getParameters();
|
||
|
|
secureRandom = parametersWithRandom.getRandom();
|
||
|
|
} else {
|
||
|
|
if (!(cipherParameters instanceof ECPublicKeyParameters)) {
|
||
|
|
throw new IllegalArgumentException("ECPublicKeyParameters are required for encryption.");
|
||
|
|
}
|
||
|
|
this.key = (ECPublicKeyParameters) cipherParameters;
|
||
|
|
secureRandom = new SecureRandom();
|
||
|
|
}
|
||
|
|
this.random = secureRandom;
|
||
|
|
}
|
||
|
|
|
||
|
|
@Override // org.bouncycastle.crypto.ec.ECEncryptor
|
||
|
|
public ECPair encrypt(ECPoint eCPoint) {
|
||
|
|
ECPublicKeyParameters eCPublicKeyParameters = this.key;
|
||
|
|
if (eCPublicKeyParameters == null) {
|
||
|
|
throw new IllegalStateException("ECElGamalEncryptor not initialised");
|
||
|
|
}
|
||
|
|
ECDomainParameters parameters = eCPublicKeyParameters.getParameters();
|
||
|
|
BigInteger generateK = ECUtil.generateK(parameters.getN(), this.random);
|
||
|
|
ECPoint[] eCPointArr = {createBasePointMultiplier().multiply(parameters.getG(), generateK), this.key.getQ().multiply(generateK).add(eCPoint)};
|
||
|
|
parameters.getCurve().normalizeAll(eCPointArr);
|
||
|
|
return new ECPair(eCPointArr[0], eCPointArr[1]);
|
||
|
|
}
|
||
|
|
|
||
|
|
protected ECMultiplier createBasePointMultiplier() {
|
||
|
|
return new FixedPointCombMultiplier();
|
||
|
|
}
|
||
|
|
}
|