private void ProcessClient(object obj)
{
TcpClient client = obj as TcpClient;
if (client == null)
{
return;
}
SessionParameters parameters = new SessionParameters()
{
ServerName = Parameters.ServerName,
MaxMessageSize = Parameters.MaxMessageSize,
ClientAddress = ((IPEndPoint)client.Client.RemoteEndPoint).Address.ToString()
};
NetworkStream stream = client.GetStream();
if (stream == null || !stream.CanRead || !stream.CanWrite)
{
return;
}
stream.ReadTimeout = 500;
SendMessage(stream, ServerCommands.CommandGreeting, parameters);
while (ParseMessage(stream, parameters))
{
;
}
client.Close();
if (MessageRecieved != null)
{
MessageRecieved(this, new MessageEventArgs(parameters));
}
}
private bool ParseMessage(NetworkStream stream, SessionParameters parameters)
{
string message = ReadMessage(stream);
if (message == null)
{
return(false);
}
if (parameters.DataReading)
{
if (string.Equals(message, ".\r\n"))
{
SendMessage(stream, ServerCommands.CommandDataAccepted, parameters);
parameters.DataReading = false;
if (string.Equals(parameters.ContentTransferEncoding, "base64", StringComparison.InvariantCultureIgnoreCase))
{
Encoding encoding = Encoding.ASCII;
if (parameters.ContentType != null)
{
try
{
encoding = Encoding.GetEncoding(parameters.ContentType.CharSet);
}
catch (Exception)
{
}
}
try
{
parameters.Message = encoding.GetString(Convert.FromBase64String(parameters.Message));
}
catch (Exception)
{
}
}
}
else
{
int index = message.IndexOf(":");
if (index >= 0)
{
string data = message.Remove(0, index).Trim(new char[] { ':', ' ', '\r', '\n' });
if (message.StartsWith("MIME-Version"))
{
parameters.MIMEVersion = data;
}
else if (message.StartsWith("From"))
{
if (!string.IsNullOrEmpty(parameters.MessageFrom))
{
parameters.MessageFrom += ", ";
}
parameters.MessageFrom += data;
}
else if (message.StartsWith("To"))
{
if (!string.IsNullOrEmpty(parameters.MessageTo))
{
parameters.MessageTo += ", ";
}
parameters.MessageTo += data;
}
else if (message.StartsWith("Cc"))
{
if (!string.IsNullOrEmpty(parameters.MessageCC))
{
parameters.MessageCC += ", ";
}
parameters.MessageCC += data;
}
else if (message.StartsWith("Reply-To"))
{
if (!string.IsNullOrEmpty(parameters.ReplyTo))
{
parameters.ReplyTo += ", ";
}
parameters.ReplyTo += data;
}
else if (message.StartsWith("Date"))
{
parameters.Date = data;
}
else if (message.StartsWith("Subject"))
{
parameters.Subject = data;
}
else if (message.StartsWith("Content-Type"))
{
parameters.ContentType = new ContentType(data);
}
else if (message.StartsWith("Content-Transfer-Encoding"))
{
parameters.ContentTransferEncoding = data;
}
else
{
parameters.Message += message;
}
}
else
{
parameters.Message += message;
}
parameters.Data += message;
}
return(true);
}
if (message.StartsWith("EHLO"))
{
if (Parameters.DisableESMTP)
{
SendMessage(stream, ServerCommands.CommandUnknown, parameters);
}
else
{
parameters.UsingESMTP = true;
parameters.Connected = true;
try
{
parameters.ClientName = message.Remove(0, 5).TrimEnd(new char[] { '\r', '\n' });
}
catch (Exception)
{
parameters.ClientName = "Unknown";
}
SendMessage(stream, ServerCommands.CommandESMTPGreeting, parameters);
SendMessage(stream, ServerCommands.CommandESMTPSize, parameters);
SendMessage(stream, ServerCommands.CommandESMTPEhlo, parameters);
SendMessage(stream, ServerCommands.CommandGetDomain, parameters);
}
}
else if (message.StartsWith("HELO"))
{
parameters.UsingESMTP = false;
parameters.Connected = true;
SendMessage(stream, ServerCommands.CommandGetDomain, parameters);
}
else
{
if (!parameters.Connected)
{
return(false);
}
if (message.StartsWith("MAIL"))
{
try
{
parameters.MailFrom.Add(message.Remove(0, 11).Trim(new char[] { '\r', '\n', '<', '>' }));
SendMessage(stream, ServerCommands.CommandFromAccepted, parameters);
}
catch (Exception)
{
SendMessage(stream, ServerCommands.CommandFromDeclined, parameters);
}
}
else if (message.StartsWith("RCPT"))
{
try
{
parameters.MailTo.Add(message.Remove(0, 9).Trim(new char[] { '\r', '\n', '<', '>' }));
if (!parameters.UsingESMTP || !stream.DataAvailable)
{
SendMessage(stream, ServerCommands.CommandToAccepted, parameters);
}
}
catch (Exception)
{
SendMessage(stream, ServerCommands.CommandToDeclined, parameters);
}
}
else if (message.StartsWith("DATA"))
{
parameters.DataReading = true;
SendMessage(stream, ServerCommands.CommandDataAcceptStarted, parameters);
}
else if (message.StartsWith("QUIT"))
{
SendMessage(stream, ServerCommands.CommandQuit, parameters);
return(false);
}
else
{
if (++parameters.UnknownCommandCount > Parameters.MaxUnknownCommandCount)
{
return(false);
}
SendMessage(stream, ServerCommands.CommandUnknown, parameters);
}
}
return(true);
}
private bool SendMessage(NetworkStream stream, string message, SessionParameters parameters)
{
message = FormatCommand(message, parameters);
return(SendMessage(stream, message));
}
public MessageEventArgs(SessionParameters parameters)
{
Parameters = parameters;
}