private void encryptButton_Click( object sender, EventArgs e )
{
Message message;
byte[] plainText = Encoding.UTF8.GetBytes( this.sendTextbox.Text );
byte[] cipherText = this.serverContext.Encrypt( plainText );
message = new Message( ProtocolOp.EncryptedMessage, cipherText );
this.server.Send( message );
}
private void HandleEncrypted( Message message )
{
this.Invoke( (Action)delegate()
{
byte[] plainText = this.serverContext.Decrypt( message.Data );
string text = Encoding.UTF8.GetString( plainText );
this.receivedTextbox.Text += "Received encrypted message from client:\r\n" + text + "\r\n";
} );
}
private void signButton_Click( object sender, EventArgs e )
{
byte[] plainText = Encoding.UTF8.GetBytes( this.sendTextbox.Text );
byte[] signedData;
Message message;
signedData = this.serverContext.MakeSignature( plainText );
message = new Message( ProtocolOp.SignedMessage, signedData );
this.server.Send( message );
}
private void HandleUnknown( Message message )
{
this.Invoke( (Action)delegate()
{
MessageBox.Show( "Received unexpected message from server. Message type: " + message.Operation );
} );
}
private void server_Received( Message message )
{
if( message.Operation == ProtocolOp.ClientToken )
{
HandleInit( message );
}
else if( message.Operation == ProtocolOp.EncryptedMessage )
{
HandleEncrypted( message );
}
else if( message.Operation == ProtocolOp.SignedMessage )
{
HandleSigned( message );
}
else
{
HandleUnknown( message );
}
}
private void HandleInit( Message message )
{
byte[] nextToken;
SecurityStatus status;
if( initializing )
{
status = this.serverContext.AcceptToken( message.Data, out nextToken );
if( status == SecurityStatus.OK || status == SecurityStatus.ContinueNeeded )
{
if( nextToken != null )
{
this.server.Send( new Message( ProtocolOp.ServerToken, nextToken ) );
}
if( status == SecurityStatus.OK )
{
this.initializing = false;
this.connected = true;
this.Invoke( (Action)delegate()
{
UpdateButtons();
this.clientUsernameTextBox.Text = serverContext.ContextUserName;
} );
}
}
else
{
this.Invoke( (Action)delegate()
{
MessageBox.Show( "Failed to accept token from client. Sspi error code: " + status );
} );
}
}
}
private void HandleSigned( Message message )
{
this.Invoke( (Action)delegate()
{
byte[] plainText;
if( this.serverContext.VerifySignature( message.Data, out plainText ) )
{
string text = Encoding.UTF8.GetString( plainText );
this.receivedTextbox.Text += "Received valid signed message from client:\r\n" + text + "\r\n";
}
else
{
this.receivedTextbox.Text += "Received *** invalid *** signed message from client.\r\n";
}
} );
}
private void signButton_Click( object sender, EventArgs e )
{
byte[] plaintext;
byte[] cipherText;
Message message;
plaintext = Encoding.UTF8.GetBytes( this.sendTextbox.Text );
cipherText = this.context.MakeSignature( plaintext );
message = new Message( ProtocolOp.SignedMessage, cipherText );
this.connection.Send( message );
}
private void HandleSigned( Message message )
{
byte[] plaintext;
string text;
if( this.context.VerifySignature( message.Data, out plaintext ) )
{
text = Encoding.UTF8.GetString( plaintext );
this.receiveTextbox.Text += "Received valid signed message from server:\r\n" + text + "\r\n";
}
else
{
this.receiveTextbox.Text += "Received *** invalid *** signed message from server.\r\n";
}
}
private void HandleEncrypted( Message message )
{
byte[] plainText = this.context.Decrypt( message.Data );
string text = Encoding.UTF8.GetString( plainText );
this.receiveTextbox.Text += "Received encrypted message from server:\r\n" + text + "\r\n";
}
private void DoInit()
{
SecurityStatus status;
byte[] outToken;
status = this.context.Init( this.lastServerToken, out outToken );
if( status == SecurityStatus.ContinueNeeded )
{
Message message = new Message( ProtocolOp.ClientToken, outToken );
this.connection.Send( message );
}
else if( status == SecurityStatus.OK )
{
this.lastServerToken = null;
this.initializing = false;
this.connected = true;
UpdateButtons();
}
}
private void connection_Received( Message message )
{
this.Invoke( (Action)delegate()
{
if( message.Operation == ProtocolOp.ServerToken )
{
if( initializing )
{
this.lastServerToken = message.Data;
DoInit();
}
else
{
MessageBox.Show( "Read unexpected operation from server: " + message.Operation );
}
}
else if( message.Operation == ProtocolOp.EncryptedMessage )
{
HandleEncrypted( message );
}
else if( message.Operation == ProtocolOp.SignedMessage )
{
HandleSigned( message );
}
} );
}