com.bouncycastle.crypto.tls.TlsRSAKeyExchange Maven / Gradle / Ivy
The newest version!
package com.bouncycastle.crypto.tls;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import com.bouncycastle.asn1.x509.KeyUsage;
import com.bouncycastle.asn1.x509.SubjectPublicKeyInfo;
import com.bouncycastle.asn1.x509.X509CertificateStructure;
import com.bouncycastle.crypto.InvalidCipherTextException;
import com.bouncycastle.crypto.encodings.PKCS1Encoding;
import com.bouncycastle.crypto.engines.RSABlindedEngine;
import com.bouncycastle.crypto.params.AsymmetricKeyParameter;
import com.bouncycastle.crypto.params.ParametersWithRandom;
import com.bouncycastle.crypto.params.RSAKeyParameters;
import com.bouncycastle.crypto.util.PublicKeyFactory;
/**
* TLS 1.0 RSA key exchange.
*/
class TlsRSAKeyExchange implements TlsKeyExchange
{
protected TlsClientContext context;
protected AsymmetricKeyParameter serverPublicKey = null;
protected RSAKeyParameters rsaServerPublicKey = null;
protected byte[] premasterSecret;
TlsRSAKeyExchange(TlsClientContext context)
{
this.context = context;
}
public void skipServerCertificate() throws IOException
{
throw new TlsFatalAlert(AlertDescription.unexpected_message);
}
public void processServerCertificate(Certificate serverCertificate) throws IOException
{
X509CertificateStructure x509Cert = serverCertificate.certs[0];
SubjectPublicKeyInfo keyInfo = x509Cert.getSubjectPublicKeyInfo();
try
{
this.serverPublicKey = PublicKeyFactory.createKey(keyInfo);
}
catch (RuntimeException e)
{
throw new TlsFatalAlert(AlertDescription.unsupported_certificate);
}
// Sanity check the PublicKeyFactory
if (this.serverPublicKey.isPrivate())
{
throw new TlsFatalAlert(AlertDescription.internal_error);
}
this.rsaServerPublicKey = validateRSAPublicKey((RSAKeyParameters)this.serverPublicKey);
TlsUtils.validateKeyUsage(x509Cert, KeyUsage.keyEncipherment);
// TODO
/*
* Perform various checks per RFC2246 7.4.2: "Unless otherwise specified, the
* signing algorithm for the certificate must be the same as the algorithm for the
* certificate key."
*/
}
public void skipServerKeyExchange() throws IOException
{
// OK
}
public void processServerKeyExchange(InputStream is)
throws IOException
{
// TODO
throw new TlsFatalAlert(AlertDescription.unexpected_message);
}
public void validateCertificateRequest(CertificateRequest certificateRequest)
throws IOException
{
short[] types = certificateRequest.getCertificateTypes();
for (int i = 0; i < types.length; ++i)
{
switch (types[i])
{
case ClientCertificateType.rsa_sign:
case ClientCertificateType.dss_sign:
case ClientCertificateType.ecdsa_sign:
break;
default:
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
}
}
public void skipClientCredentials() throws IOException
{
// OK
}
public void processClientCredentials(TlsCredentials clientCredentials) throws IOException
{
if (!(clientCredentials instanceof TlsSignerCredentials))
{
throw new TlsFatalAlert(AlertDescription.internal_error);
}
}
public void generateClientKeyExchange(OutputStream os) throws IOException
{
/*
* Choose a PremasterSecret and send it encrypted to the server
*/
premasterSecret = new byte[48];
context.getSecureRandom().nextBytes(premasterSecret);
TlsUtils.writeVersion(premasterSecret, 0);
PKCS1Encoding encoding = new PKCS1Encoding(new RSABlindedEngine());
encoding.init(true, new ParametersWithRandom(this.rsaServerPublicKey, context.getSecureRandom()));
try
{
byte[] keData = encoding.processBlock(premasterSecret, 0, premasterSecret.length);
TlsUtils.writeUint24(keData.length + 2, os);
TlsUtils.writeOpaque16(keData, os);
}
catch (InvalidCipherTextException e)
{
/*
* This should never happen, only during decryption.
*/
throw new TlsFatalAlert(AlertDescription.internal_error);
}
}
public byte[] generatePremasterSecret() throws IOException
{
byte[] tmp = this.premasterSecret;
this.premasterSecret = null;
return tmp;
}
// Would be needed to process RSA_EXPORT server key exchange
// protected void processRSAServerKeyExchange(InputStream is, Signer signer) throws IOException
// {
// InputStream sigIn = is;
// if (signer != null)
// {
// sigIn = new SignerInputStream(is, signer);
// }
//
// byte[] modulusBytes = TlsUtils.readOpaque16(sigIn);
// byte[] exponentBytes = TlsUtils.readOpaque16(sigIn);
//
// if (signer != null)
// {
// byte[] sigByte = TlsUtils.readOpaque16(is);
//
// if (!signer.verifySignature(sigByte))
// {
// handler.failWithError(AlertLevel.fatal, AlertDescription.bad_certificate);
// }
// }
//
// BigInteger modulus = new BigInteger(1, modulusBytes);
// BigInteger exponent = new BigInteger(1, exponentBytes);
//
// this.rsaServerPublicKey = validateRSAPublicKey(new RSAKeyParameters(false, modulus,
// exponent));
// }
protected RSAKeyParameters validateRSAPublicKey(RSAKeyParameters key) throws IOException
{
// TODO What is the minimum bit length required?
// key.getModulus().bitLength();
if (!key.getExponent().isProbablePrime(2))
{
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
return key;
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy