private byte[] EncryptRequest(Request request, EncryptionProvider crypter)
{
try
{
byte[] requestData = formatter.Format(request);
return(crypter.Encrypt(requestData));
}
catch (CryptographicException ex)
{
if (CryptoError != null)
{
CryptoError(request, ex);
}
return(null);
}
}
private void Server_DataRecieved(string host, byte[] requestData)
{
// Match host session
var session = sessions.GetSession(host);
if (session == null)
{
if (UnknownSession != null)
{
UnknownSession(string.Format("Session not found for host: {0}.", host));
}
return;
}
// Commit request session phase
Request request = null;
if (session.CurrentPhase == SessionPhase.Hello)
{
request = MatchRequest <HelloRequest>(requestData);
if (request == null)
{
return;
}
}
else if (session.CurrentPhase == SessionPhase.Encryption)
{
var data = DecryptRequest(requestData, asymetricCrypter);
if (data == null)
{
return;
}
request = MatchRequest <KeyExchangeRequest>(data);
}
else if (session.CurrentPhase == SessionPhase.Authentication)
{
var data = DecryptRequest(requestData, session.Crpter);
if (data == null)
{
return;
}
request = MatchRequest <AuthenticateRequest>(data);
}
else
{
var data = DecryptRequest(requestData, session.Crpter);
if (data == null)
{
return;
}
request = MatchRequest <Request>(data);
}
request.Session = session;
Response response = null;
// Authenitacate request user
AuthenticationResult result = AuthenticationResult.Denied;
if (request.RequiresAuthentication)
{
string password = session.Crpter.DecryptString(request.User.PasswordEnc);
result = authenticator.Authenticate(request.User, password);
}
if (!request.RequiresAuthentication || result == AuthenticationResult.Granted)
{
// Check user permissions for request (authorize request user)
Permission[] permissions = null;
if (request.RequiresAuthorization)
{
permissions = authorizator.ListPermissions(request.User);
}
if (!request.RequiresAuthorization || request.MatchesPermissions(permissions))
{
try
{
// EXECUTE REQUEST
ProgramOutput.Info("Executing request: {0}...", request.ToString());
response = request.Execute();
}
catch (Exception ex)
{
response = new CannotExecuteResponse(ex);
if (ExecuteError != null)
{
ExecuteError(request, ex);
}
}
}
else
{
response = new AccessDeniedResponse();
if (AccessDenied != null)
{
AccessDenied(request);
}
}
}
else if (result == AuthenticationResult.Denied)
{
response = new UnauthorizedResponse(request.User);
if (Unauthorized != null)
{
Unauthorized(request);
}
}
if (!(request is GoodbyeRequest))
{
// Serialize response
byte[] responseData = null;
try
{
responseData = formatter.Format(response);
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
if (InvalidResponse != null)
{
InvalidResponse(request);
}
return;
}
// Encrypt response
if (session.CurrentPhase == SessionPhase.Authentication || session.CurrentPhase == SessionPhase.Established)
{
responseData = EncryptResponse(responseData, session.Crpter);
}
if (responseData == null)
{
return;
}
// Send response
try
{
ProgramOutput.Info("Responding: {0}, status code: {1}", response, response.Code);
server.SendMessage(host, responseData);
}
catch (SocketException)
{
if (NetProblem != null)
{
NetProblem(request);
}
return;
}
session.NextPhase();
}
}
