using System;
using System.IO;
using System.ComponentModel;
using System.Collections;
using System.Diagnostics;
using System.Net;
using System.Net.Sockets;
using System.Threading;
using System.Security.Cryptography.X509Certificates;
using LumiSoft.Net;
using LumiSoft.Net.AUTH;
namespace LumiSoft.Net.SMTP.Server
{
#region Event delegates
/// <summary>
/// Represents the method that will handle the AuthUser event for SMTP_Server.
/// </summary>
/// <param name="sender">The source of the event. </param>
/// <param name="e">A AuthUser_EventArgs that contains the event data.</param>
public delegate void AuthUserEventHandler(object sender,AuthUser_EventArgs e);
/// <summary>
/// Represents the method that will handle the ValidateMailFrom event for SMTP_Server.
/// </summary>
/// <param name="sender">The source of the event. </param>
/// <param name="e">A ValidateSender_EventArgs that contains the event data.</param>
public delegate void ValidateMailFromHandler(object sender,ValidateSender_EventArgs e);
/// <summary>
/// Represents the method that will handle the ValidateMailTo event for SMTP_Server.
/// </summary>
/// <param name="sender">The source of the event. </param>
/// <param name="e">A ValidateRecipient_EventArgs that contains the event data.</param>
public delegate void ValidateMailToHandler(object sender,ValidateRecipient_EventArgs e);
/// <summary>
/// Represents the method that will handle the ValidateMailboxSize event for SMTP_Server.
/// </summary>
/// <param name="sender">The source of the event. </param>
/// <param name="e">A ValidateMailboxSize_EventArgs that contains the event data.</param>
public delegate void ValidateMailboxSize(object sender,ValidateMailboxSize_EventArgs e);
/// <summary>
/// Represents the method that will handle the GetMessageStoreStream event for SMTP_Server.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A GetMessageStoreStream_eArgs that contains the event data.</param>
public delegate void GetMessageStoreStreamHandler(object sender,GetMessageStoreStream_eArgs e);
/// <summary>
/// Represents the method that will handle the MessageStoringCompleted event for SMTP_Server.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A MessageStoringCompleted_eArgs that contains the event data.</param>
public delegate void MessageStoringCompletedHandler(object sender,MessageStoringCompleted_eArgs e);
#endregion
/// <summary>
/// SMTP server component.
/// </summary>
public class SMTP_Server : SocketServer
{
private int m_MaxConnectionsPerIP = 0;
private int m_MaxMessageSize = 1000000;
private int m_MaxRecipients = 100;
private SaslAuthTypes m_SupportedAuth = SaslAuthTypes.All;
private string m_GreetingText = "";
#region Event declarations
/// <summary>
/// Occurs when new computer connected to SMTP server.
/// </summary>
public event ValidateIPHandler ValidateIPAddress = null;
/// <summary>
/// Occurs when connected user tryes to authenticate.
/// </summary>
public event AuthUserEventHandler AuthUser = null;
/// <summary>
/// Occurs when server needs to validate sender.
/// </summary>
public event ValidateMailFromHandler ValidateMailFrom = null;
/// <summary>
/// Occurs when server needs to validate recipient.
/// </summary>
public event ValidateMailToHandler ValidateMailTo = null;
/// <summary>
/// Occurs when server needs to validate recipient mailbox size.
/// </summary>
public event ValidateMailboxSize ValidateMailboxSize = null;
/// <summary>
/// Occurs when server needs to get stream where to store incoming message.
/// </summary>
public event GetMessageStoreStreamHandler GetMessageStoreStream = null;
/// <summary>
/// Occurs when server has finished message storing.
/// </summary>
public event MessageStoringCompletedHandler MessageStoringCompleted = null;
/// <summary>
/// Occurs when SMTP session log is available.
/// </summary>
public event LogEventHandler SessionLog = null;
#endregion
/// <summary>
/// Defalut constructor.
/// </summary>
public SMTP_Server() : base()
{
this.BindInfo = new BindInfo[]{new BindInfo(IPAddress.Any,25,false,null)};
}
#region override InitNewSession
/// <summary>
/// Initialize and start new session here. Session isn't added to session list automatically,
/// session must add itself to server session list by calling AddSession().
/// </summary>
/// <param name="socket">Connected client socket.</param>
/// <param name="bindInfo">BindInfo what accepted socket.</param>
protected override void InitNewSession(Socket socket,BindInfo bindInfo)
{
// Check maximum conncurent connections from 1 IP.
if(m_MaxConnectionsPerIP > 0){
lock(this.Sessions){
int nSessions = 0;
foreach(SocketServerSession s in this.Sessions){
IPEndPoint ipEndpoint = s.RemoteEndPoint;
if(ipEndpoint != null){
if(ipEndpoint.Address.Equals(((IPEndPoint)socket.RemoteEndPoint).Address)){
nSessions++;
}
}
// Maimum allowed exceeded
if(nSessions >= m_MaxConnectionsPerIP){
socket.Send(System.Text.Encoding.ASCII.GetBytes("421 Maximum connections from your IP address is exceeded, try again later !\r\n"));
socket.Shutdown(SocketShutdown.Both);
socket.Close();
return;
}
}
}
}
string sessionID = Guid.NewGuid().ToString();
SocketEx socketEx = new SocketEx(socket);
if(LogCommands){
socketEx.Logger = new SocketLogger(socket,this.SessionLog);
socketEx.Logger.SessionID = sessionID;
}
SMTP_Session session = new SMTP_Session(sessionID,socketEx,bindInfo,this);
}
#endregion
#region Properties Implementaion
/// <summary>
/// Gets or sets server greeting text.
/// </summary>
public string GreetingText
{
get{ return m_GreetingText; }
set{ m_GreetingText = value; }
}
/// <summary>
/// Gets or sets maximum allowed conncurent connections from 1 IP address. Value 0 means unlimited connections.
/// </summary>
public int MaxConnectionsPerIP
{
get{ return m_MaxConnectionsPerIP; }
set{ m_MaxConnectionsPerIP = value; }
}
/// <summary>
/// Maximum message size in bytes.
/// </summary>
public int MaxMessageSize
{
get{ return m_MaxMessageSize; }
set{ m_MaxMessageSize = value; }
}
/// <summary>
/// Maximum recipients per message.
/// </summary>
public int MaxRecipients
{
get{ return m_MaxRecipients; }
set{ m_MaxRecipients = value; }
}
/// <summary>
/// Gets or sets server supported authentication types.
/// </summary>
public SaslAuthTypes SupportedAuthentications
{
get{ return m_SupportedAuth; }
set{ m_SupportedAuth = value; }
}
/// <summary>
/// Gets active sessions.
/// </summary>
public new SMTP_Session[] Sessions
{
get{
SocketServerSession[] sessions = base.Sessions;
SMTP_Session[] smtpSessions = new SMTP_Session[sessions.Length];
sessions.CopyTo(smtpSessions,0);
return smtpSessions;
}
}
#endregion
#region Events Implementation
#region method OnValidate_IpAddress
/// <summary>
/// Raises event ValidateIP event.
/// </summary>
/// <param name="session">Reference to current smtp session.</param>
internal ValidateIP_EventArgs OnValidate_IpAddress(SMTP_Session session)
{
ValidateIP_EventArgs oArg = new ValidateIP_EventArgs(session.LocalEndPoint,session.RemoteEndPoint);
if(this.ValidateIPAddress != null){
this.ValidateIPAddress(this, oArg);
}
session.Tag = oArg.SessionTag;
return oArg;
}
#endregion
#region method OnAuthUser
/// <summary>
/// Raises event AuthUser.
/// </summary>
/// <param name="session">Reference to current smtp session.</param>
/// <param name="userName">User name.</param>
/// <param name="passwordData">Password compare data,it depends of authentication type.</param>
/// <param name="data">For md5 eg. md5 calculation hash.It depends of authentication type.</param>
/// <param name="authType">Authentication type.</param>
/// <returns></returns>
internal AuthUser_EventArgs OnAuthUser(SMTP_Session session,string userName,string passwordData,string data,AuthType authType)
{
AuthUser_EventArgs oArgs = new AuthUser_EventArgs(session,userName,passwordData,data,authType);
if(this.AuthUser != null){
this.AuthUser(this,oArgs);
}
return oArgs;
}
#endregion
#region method OnValidate_MailFrom
/// <summary>
/// Raises event ValidateMailFrom.
/// </summary>
/// <param name="session"></param>
/// <param name="reverse_path"></param>
/// <param name="email"></param>
/// <returns></returns>
internal ValidateSender_EventArgs OnValidate_MailFrom(SMTP_Session session,string reverse_path,string email)
{
ValidateSender_EventArgs oArg = new ValidateSender_EventArgs(session,email);
if(this.ValidateMailFrom != null){
this.ValidateMailFrom(this, oArg);
}
return oArg;
}
#endregion
#region method OnValidate_MailTo
/// <summary>
/// Raises event ValidateMailTo.
/// </summary>
/// <param name="session"></param>
/// <param name="forward_path"></param>
/// <param name="email"></param>
/// <param name="authenticated"></param>
/// <returns></returns>
internal ValidateRecipient_EventArgs OnValidate_MailTo(SMTP_Session session,string forward_path,string email,bool authenticated)
{
ValidateRecipient_EventArgs oArg = new ValidateRecipient_EventArgs(session,email,authenticated);
if(this.ValidateMailTo != null){
this.ValidateMailTo(this, oArg);
}
return oArg;
}
#endregion
#region method Validate_MailBoxSize
/// <summary>
/// Raises event ValidateMailboxSize.
/// </summary>
/// <param name="session"></param>
/// <param name="eAddress"></param>
/// <param name="messageSize"></param>
/// <returns></returns>
internal bool Validate_MailBoxSize(SMTP_Session session,string eAddress,long messageSize)
{
ValidateMailboxSize_EventArgs oArgs = new ValidateMailboxSize_EventArgs(session,eAddress,messageSize);
if(this.ValidateMailboxSize != null){
this.ValidateMailboxSize(this,oArgs);
}
return oArgs.IsValid;
}
#endregion
#region method OnGetMessageStoreStream
/// <summary>
/// Raises event GetMessageStoreStream.
/// </summary>
/// <param name="session">Reference to calling SMTP session.</param>
/// <returns></returns>
internal GetMessageStoreStream_eArgs OnGetMessageStoreStream(SMTP_Session session)
{
GetMessageStoreStream_eArgs eArgs = new GetMessageStoreStream_eArgs(session);
if(this.GetMessageStoreStream != null){
this.GetMessageStoreStream(this,eArgs);
}
return eArgs;
}
#endregion
#region method OnMessageStoringCompleted
/// <summary>
/// Raises event MessageStoringCompleted.
/// </summary>
/// <param name="session">Reference to calling SMTP session.</param>
/// <param name="errorText">Null if no errors, otherwise conatians error text. If errors happened that means that messageStream is incomplete.</param>
/// <param name="messageStream">Stream where message was stored.</param>
internal MessageStoringCompleted_eArgs OnMessageStoringCompleted(SMTP_Session session,string errorText,Stream messageStream)
{
MessageStoringCompleted_eArgs eArgs = new MessageStoringCompleted_eArgs(session,errorText,messageStream);
if(this.MessageStoringCompleted != null){
this.MessageStoringCompleted(this,eArgs);
}
return eArgs;
}
#endregion
#endregion
}
}
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