org.bouncycastle.crypto.agreement.kdf.ECDHKEKGenerator Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of bcprov-ext-debug-jdk15on Show documentation
Show all versions of bcprov-ext-debug-jdk15on Show documentation
The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms. This jar contains JCE provider and lightweight API for the Bouncy Castle Cryptography APIs for JDK 1.5 to JDK 1.8 with debug enabled.
package org.bouncycastle.crypto.agreement.kdf;
import java.io.IOException;
import org.bouncycastle.asn1.ASN1EncodableVector;
import org.bouncycastle.asn1.ASN1Encoding;
import org.bouncycastle.asn1.ASN1ObjectIdentifier;
import org.bouncycastle.asn1.DERNull;
import org.bouncycastle.asn1.DEROctetString;
import org.bouncycastle.asn1.DERSequence;
import org.bouncycastle.asn1.DERTaggedObject;
import org.bouncycastle.asn1.x509.AlgorithmIdentifier;
import org.bouncycastle.crypto.DataLengthException;
import org.bouncycastle.crypto.DerivationParameters;
import org.bouncycastle.crypto.Digest;
import org.bouncycastle.crypto.DigestDerivationFunction;
import org.bouncycastle.crypto.generators.KDF2BytesGenerator;
import org.bouncycastle.crypto.params.KDFParameters;
import org.bouncycastle.util.Pack;
/**
* X9.63 based key derivation function for ECDH CMS.
*/
public class ECDHKEKGenerator
implements DigestDerivationFunction
{
private DigestDerivationFunction kdf;
private ASN1ObjectIdentifier algorithm;
private int keySize;
private byte[] z;
public ECDHKEKGenerator(
Digest digest)
{
this.kdf = new KDF2BytesGenerator(digest);
}
public void init(DerivationParameters param)
{
DHKDFParameters params = (DHKDFParameters)param;
this.algorithm = params.getAlgorithm();
this.keySize = params.getKeySize();
this.z = params.getZ();
}
public Digest getDigest()
{
return kdf.getDigest();
}
public int generateBytes(byte[] out, int outOff, int len)
throws DataLengthException, IllegalArgumentException
{
// TODO Create an ASN.1 class for this (RFC3278)
// ECC-CMS-SharedInfo
ASN1EncodableVector v = new ASN1EncodableVector();
v.add(new AlgorithmIdentifier(algorithm, DERNull.INSTANCE));
v.add(new DERTaggedObject(true, 2, new DEROctetString(Pack.intToBigEndian(keySize))));
try
{
kdf.init(new KDFParameters(z, new DERSequence(v).getEncoded(ASN1Encoding.DER)));
}
catch (IOException e)
{
throw new IllegalArgumentException("unable to initialise kdf: " + e.getMessage());
}
return kdf.generateBytes(out, outOff, len);
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy