org.bouncycastle.tls.DTLSProtocol Maven / Gradle / Ivy
package org.bouncycastle.tls;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Hashtable;
import java.util.Vector;
import org.bouncycastle.util.Arrays;
public abstract class DTLSProtocol
{
protected DTLSProtocol()
{
}
protected void processFinished(byte[] body, byte[] expected_verify_data)
throws IOException
{
ByteArrayInputStream buf = new ByteArrayInputStream(body);
byte[] verify_data = TlsUtils.readFully(expected_verify_data.length, buf);
TlsProtocol.assertEmpty(buf);
if (!Arrays.constantTimeAreEqual(expected_verify_data, verify_data))
{
throw new TlsFatalAlert(AlertDescription.handshake_failure);
}
}
protected static void applyMaxFragmentLengthExtension(DTLSRecordLayer recordLayer, short maxFragmentLength)
throws IOException
{
if (maxFragmentLength >= 0)
{
if (!MaxFragmentLength.isValid(maxFragmentLength))
{
throw new TlsFatalAlert(AlertDescription.internal_error);
}
int plainTextLimit = 1 << (8 + maxFragmentLength);
recordLayer.setPlaintextLimit(plainTextLimit);
}
}
protected static short evaluateMaxFragmentLengthExtension(boolean resumedSession, Hashtable clientExtensions,
Hashtable serverExtensions, short alertDescription) throws IOException
{
short maxFragmentLength = TlsExtensionsUtils.getMaxFragmentLengthExtension(serverExtensions);
if (maxFragmentLength >= 0)
{
if (!MaxFragmentLength.isValid(maxFragmentLength)
|| (!resumedSession && maxFragmentLength != TlsExtensionsUtils
.getMaxFragmentLengthExtension(clientExtensions)))
{
throw new TlsFatalAlert(alertDescription);
}
}
return maxFragmentLength;
}
protected static byte[] generateCertificate(TlsContext context, Certificate certificate, OutputStream endPointHash)
throws IOException
{
ByteArrayOutputStream buf = new ByteArrayOutputStream();
certificate.encode(context, buf, endPointHash);
return buf.toByteArray();
}
protected static byte[] generateSupplementalData(Vector supplementalData)
throws IOException
{
ByteArrayOutputStream buf = new ByteArrayOutputStream();
TlsProtocol.writeSupplementalData(buf, supplementalData);
return buf.toByteArray();
}
protected static void sendCertificateMessage(TlsContext context, DTLSReliableHandshake handshake,
Certificate certificate, OutputStream endPointHash) throws IOException
{
SecurityParameters securityParameters = context.getSecurityParametersHandshake();
if (null != securityParameters.getLocalCertificate())
{
throw new TlsFatalAlert(AlertDescription.internal_error);
}
if (null == certificate)
{
certificate = Certificate.EMPTY_CHAIN;
}
byte[] certificateBody = generateCertificate(context, certificate, endPointHash);
handshake.sendMessage(HandshakeType.certificate, certificateBody);
securityParameters.localCertificate = certificate;
}
protected static int validateSelectedCipherSuite(int selectedCipherSuite, short alertDescription)
throws IOException
{
switch (TlsUtils.getEncryptionAlgorithm(selectedCipherSuite))
{
case EncryptionAlgorithm.RC4_40:
case EncryptionAlgorithm.RC4_128:
case -1:
throw new TlsFatalAlert(alertDescription);
default:
return selectedCipherSuite;
}
}
}