protected override void ProcessFinished(HandshakeMessage finished)
{
if (_state != HandshakeState.ReceivedChangeCipherSpec)
{
throw new AlertException(AlertDescription.UnexpectedMessage,
"Finished received at the wrong time");
}
byte[] allMessages = _handshakeStream.ToArray();
byte[] handshakeMessages = new byte[allMessages.Length - finished.Encode().Length];
Buffer.BlockCopy(allMessages, 0, handshakeMessages, 0, handshakeMessages.Length);
PseudoRandomFunction prf = _cipherSuite.PseudoRandomFunction;
HashAlgorithm verifyHash = prf.CreateVerifyHashAlgorithm(_connectionState.MasterSecret);
verifyHash.TransformBlock(handshakeMessages, 0, handshakeMessages.Length, handshakeMessages, 0);
byte[] ourVerifyData;
if (_version == ProtocolVersion.SSL3_0)
{
byte[] senderBytes = Encoding.ASCII.GetBytes("CLNT");
verifyHash.TransformFinalBlock(senderBytes, 0, senderBytes.Length);
ourVerifyData = verifyHash.Hash;
}
else
{
verifyHash.TransformFinalBlock(new byte[0], 0, 0);
byte[] hash = verifyHash.Hash;
int length = _cipherSuite.PseudoRandomFunction.VerifyDataLength;
ourVerifyData = _cipherSuite.PseudoRandomFunction.GetBytes(_connectionState.MasterSecret, "client finished", hash, length);
}
// Verify that the received data matches ours
bool verifyOk = false;
if (ourVerifyData.Length == finished.Data.Length)
{
verifyOk = true;
for (int i = 0; i < ourVerifyData.Length; i++)
{
if (ourVerifyData[i] != finished.Data[i])
{
verifyOk = false;
}
}
}
if (!verifyOk)
{
throw new AlertException(AlertDescription.DecryptError,
"Finished packet contents incorrect");
}
_connectionState.ClientVerifyData = ourVerifyData;
// Send our own change cipher spec
_state = HandshakeState.SendChangeCipherSpec;
}
public void SendFinished(Stream stream)
{
Record record;
/* change cipher spec */
record = new Record(20, VERSION);
record.Fragment = new byte[] { 0x01 };
_recordHandler.ProcessOutputRecord(record);
SendRecord(stream, record);
/* change our own cipher spec */
_recordHandler.ChangeLocalState();
ProtocolVersion version = VERSION;
byte[] handshakeMessages = _handshakeStream.ToArray();
Console.WriteLine("handshake messages length " + handshakeMessages.Length);
PseudoRandomFunction prf = _cipherSuite.PseudoRandomFunction;
HashAlgorithm verifyHash = prf.CreateVerifyHashAlgorithm(_masterSecret);
verifyHash.TransformBlock(handshakeMessages, 0, handshakeMessages.Length, handshakeMessages, 0);
byte[] verifyData;
if (version == ProtocolVersion.SSL3_0)
{
byte[] senderBytes = Encoding.ASCII.GetBytes("CLNT");
verifyHash.TransformFinalBlock(senderBytes, 0, senderBytes.Length);
verifyData = verifyHash.Hash;
}
else
{
verifyHash.TransformFinalBlock(new byte[0], 0, 0);
byte[] hash = verifyHash.Hash;
int length = _cipherSuite.PseudoRandomFunction.VerifyDataLength;
verifyData = _cipherSuite.PseudoRandomFunction.GetBytes(_masterSecret, "client finished", hash, length);
}
HandshakeMessage finished = new HandshakeMessage(HandshakeMessageType.Finished, VERSION, verifyData);
PrintBytes("verify data", finished.Data);
record = new Record(22, VERSION);
record.Fragment = finished.Encode();
_recordHandler.ProcessOutputRecord(record);
SendRecord(stream, record);
Console.WriteLine("encrypted finished sent");
}
protected override void ProcessLocalChangeCipherSpec()
{
if (_state != HandshakeState.SendChangeCipherSpec)
{
throw new AlertException(AlertDescription.UnexpectedMessage,
"Change cipher spec not after server hello done");
}
byte[] handshakeMessages = _handshakeStream.ToArray();
PseudoRandomFunction prf = _cipherSuite.PseudoRandomFunction;
HashAlgorithm verifyHash = prf.CreateVerifyHashAlgorithm(_connectionState.MasterSecret);
verifyHash.TransformBlock(handshakeMessages, 0, handshakeMessages.Length, handshakeMessages, 0);
byte[] verifyData;
if (_version == ProtocolVersion.SSL3_0)
{
byte[] senderBytes = Encoding.ASCII.GetBytes("SRVR");
verifyHash.TransformFinalBlock(senderBytes, 0, senderBytes.Length);
verifyData = verifyHash.Hash;
}
else
{
verifyHash.TransformFinalBlock(new byte[0], 0, 0);
byte[] hash = verifyHash.Hash;
int length = _cipherSuite.PseudoRandomFunction.VerifyDataLength;
verifyData = _cipherSuite.PseudoRandomFunction.GetBytes(_connectionState.MasterSecret, "server finished", hash, length);
}
_connectionState.ServerVerifyData = verifyData;
HandshakeMessage finished = new HandshakeMessage(HandshakeMessageType.Finished, _version, verifyData);
OutputMessage(finished);
// Cleanup the handshake stream used for verify hashes
_handshakeStream = new MemoryStream();
// Everything done and handshake finished
_state = HandshakeState.Finished;
}
