package org.bouncycastle.jcajce.provider.asymmetric.dsa;
import java.io.IOException;
import java.math.BigInteger;
import java.security.InvalidKeyException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.SignatureException;
import java.security.SignatureSpi;
import java.security.interfaces.DSAKey;
import java.security.spec.AlgorithmParameterSpec;
import org.bouncycastle.asn1.ASN1Encoding;
import org.bouncycastle.asn1.ASN1Integer;
import org.bouncycastle.asn1.ASN1Primitive;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.DERSequence;
import org.bouncycastle.asn1.pkcs.PKCSObjectIdentifiers;
import org.bouncycastle.asn1.x509.SubjectPublicKeyInfo;
import org.bouncycastle.asn1.x509.X509ObjectIdentifiers;
import org.bouncycastle.crypto.CipherParameters;
import org.bouncycastle.crypto.DSA;
import org.bouncycastle.crypto.Digest;
import org.bouncycastle.crypto.digests.NullDigest;
import org.bouncycastle.crypto.digests.SHA1Digest;
import org.bouncycastle.crypto.digests.SHA224Digest;
import org.bouncycastle.crypto.digests.SHA256Digest;
import org.bouncycastle.crypto.digests.SHA384Digest;
import org.bouncycastle.crypto.digests.SHA512Digest;
import org.bouncycastle.crypto.params.ParametersWithRandom;
public class DSASigner
extends SignatureSpi
implements PKCSObjectIdentifiers, X509ObjectIdentifiers
{
private Digest digest;
private DSA signer;
private SecureRandom random;
protected DSASigner(
Digest digest,
DSA signer)
{
this.digest = digest;
this.signer = signer;
}
protected void engineInitVerify(
PublicKey publicKey)
throws InvalidKeyException
{
CipherParameters param;
if (publicKey instanceof DSAKey)
{
param = DSAUtil.generatePublicKeyParameter(publicKey);
}
else
{
try
{
byte[] bytes = publicKey.getEncoded();
publicKey = new BCDSAPublicKey(SubjectPublicKeyInfo.getInstance(bytes));
if (publicKey instanceof DSAKey)
{
param = DSAUtil.generatePublicKeyParameter(publicKey);
}
else
{
throw new InvalidKeyException("can't recognise key type in DSA based signer");
}
}
catch (Exception e)
{
throw new InvalidKeyException("can't recognise key type in DSA based signer");
}
}
digest.reset();
signer.init(false, param);
}
protected void engineInitSign(
PrivateKey privateKey,
SecureRandom random)
throws InvalidKeyException
{
this.random = random;
engineInitSign(privateKey);
}
protected void engineInitSign(
PrivateKey privateKey)
throws InvalidKeyException
{
CipherParameters param;
param = DSAUtil.generatePrivateKeyParameter(privateKey);
if (random != null)
{
param = new ParametersWithRandom(param, random);
}
digest.reset();
signer.init(true, param);
}
protected void engineUpdate(
byte b)
throws SignatureException
{
digest.update(b);
}
protected void engineUpdate(
byte[] b,
int off,
int len)
throws SignatureException
{
digest.update(b, off, len);
}
protected byte[] engineSign()
throws SignatureException
{
byte[] hash = new byte[digest.getDigestSize()];
digest.doFinal(hash, 0);
try
{
BigInteger[] sig = signer.generateSignature(hash);
return derEncode(sig[0], sig[1]);
}
catch (Exception e)
{
throw new SignatureException(e.toString());
}
}
protected boolean engineVerify(
byte[] sigBytes)
throws SignatureException
{
byte[] hash = new byte[digest.getDigestSize()];
digest.doFinal(hash, 0);
BigInteger[] sig;
try
{
sig = derDecode(sigBytes);
}
catch (Exception e)
{
throw new SignatureException("error decoding signature bytes.");
}
return signer.verifySignature(hash, sig[0], sig[1]);
}
protected void engineSetParameter(
AlgorithmParameterSpec params)
{
throw new UnsupportedOperationException("engineSetParameter unsupported");
}
/**
* @deprecated replaced with <a href = "#engineSetParameter(java.security.spec.AlgorithmParameterSpec)">
*/
protected void engineSetParameter(
String param,
Object value)
{
throw new UnsupportedOperationException("engineSetParameter unsupported");
}
/**
* @deprecated
*/
protected Object engineGetParameter(
String param)
{
throw new UnsupportedOperationException("engineSetParameter unsupported");
}
private byte[] derEncode(
BigInteger r,
BigInteger s)
throws IOException
{
ASN1Integer[] rs = new ASN1Integer[]{ new ASN1Integer(r), new ASN1Integer(s) };
return new DERSequence(rs).getEncoded(ASN1Encoding.DER);
}
private BigInteger[] derDecode(
byte[] encoding)
throws IOException
{
ASN1Sequence s = (ASN1Sequence)ASN1Primitive.fromByteArray(encoding);
return new BigInteger[]{
((ASN1Integer)s.getObjectAt(0)).getValue(),
((ASN1Integer)s.getObjectAt(1)).getValue()
};
}
static public class stdDSA
extends DSASigner
{
public stdDSA()
{
super(new SHA1Digest(), new org.bouncycastle.crypto.signers.DSASigner());
}
}
static public class dsa224
extends DSASigner
{
public dsa224()
{
super(new SHA224Digest(), new org.bouncycastle.crypto.signers.DSASigner());
}
}
static public class dsa256
extends DSASigner
{
public dsa256()
{
super(new SHA256Digest(), new org.bouncycastle.crypto.signers.DSASigner());
}
}
static public class dsa384
extends DSASigner
{
public dsa384()
{
super(new SHA384Digest(), new org.bouncycastle.crypto.signers.DSASigner());
}
}
static public class dsa512
extends DSASigner
{
public dsa512()
{
super(new SHA512Digest(), new org.bouncycastle.crypto.signers.DSASigner());
}
}
static public class noneDSA
extends DSASigner
{
public noneDSA()
{
super(new NullDigest(), new org.bouncycastle.crypto.signers.DSASigner());
}
}
}