listensocket.cpp

非常难得的eMule(电骡) V0.45b 源码下载 值得研究

//this file is part of eMule
//Copyright (C)2002 Merkur ( [e-mail] / http://www.emule-project.net )
//
//This program is free software; you can redistribute it and/or
//modify it under the terms of the GNU General Public License
//as published by the Free Software Foundation; either
//version 2 of the License, or (at your option) any later version.
//
//This program is distributed in the hope that it will be useful,
//but WITHOUT ANY WARRANTY; without even the implied warranty of
//MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//GNU General Public License for more details.
//
//You should have received a copy of the GNU General Public License
//along with this program; if not, write to the Free Software
//Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#include "stdafx.h"
#include "DebugHelpers.h"
#include "emule.h"
#include "ListenSocket.h"
#include "PeerCacheSocket.h"
#include "opcodes.h"
#include "UpDownClient.h"
#include "ClientList.h"
#include "OtherFunctions.h"
#include "DownloadQueue.h"
#include "Statistics.h"
#include "IPFilter.h"
#include "SharedFileList.h"
#include "PartFile.h"
#include "SafeFile.h"
#include "Packets.h"
#include "UploadQueue.h"
#include "ServerList.h"
#include "Server.h"
#include "Sockets.h"
#include "emuledlg.h"
#include "TransferWnd.h"
#include "ClientListCtrl.h"
#include "ChatWnd.h"
#include "PeerCacheFinder.h"
#include "Exceptions.h"
#include "Kademlia/Utils/uint128.h"
#include "Kademlia/Kademlia/kademlia.h"
#include "Kademlia/Kademlia/prefs.h"
#include "ClientUDPSocket.h"
#include "SHAHashSet.h"
#include "Log.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif


// CClientReqSocket

IMPLEMENT_DYNCREATE(CClientReqSocket, CEMSocket)

CClientReqSocket::CClientReqSocket(CUpDownClient* in_client)
{
	SetClient(in_client);
	theApp.listensocket->AddSocket(this);
	ResetTimeOutTimer();
	deletethis = false;
	deltimer = 0;
	m_bPortTestCon=false;
	m_nOnConnect=SS_Other;
}

void CClientReqSocket::SetConState( SocketState val )
{
	//If no change, do nothing..
	if( val == m_nOnConnect )
		return;
	//Decrease count of old state..
	switch( m_nOnConnect )
	{
		case SS_Half:
			theApp.listensocket->m_nHalfOpen--;
			break;
		case SS_Complete:
			theApp.listensocket->m_nComp--;
	}
	//Set state to new state..
	m_nOnConnect = val;
	//Increase count of new state..
	switch( m_nOnConnect )
	{
		case SS_Half:
			theApp.listensocket->m_nHalfOpen++;
			break;
		case SS_Complete:
			theApp.listensocket->m_nComp++;
	}
}

void CClientReqSocket::WaitForOnConnect()
{
	SetConState(SS_Half);
}
	
CClientReqSocket::~CClientReqSocket()
{
	//This will update our statistics.
	SetConState(SS_Other);
	if (client)
		client->socket = 0;
	client = 0;
	theApp.listensocket->RemoveSocket(this);

	DEBUG_ONLY (theApp.clientlist->Debug_SocketDeleted(this));
}

void CClientReqSocket::SetClient(CUpDownClient* pClient)
{
	client = pClient;
	if (client)
		client->socket = this;
}

void CClientReqSocket::ResetTimeOutTimer(){
	timeout_timer = ::GetTickCount();
}

UINT CClientReqSocket::GetTimeOut()
{
	// PC-TODO
	// the PC socket may even already be disconnected and deleted and we still need to keep the
	// ed2k socket open because remote client may still be downloading from cache.
	if (client && client->IsUploadingToPeerCache() && (client->m_pPCUpSocket == NULL || !client->m_pPCUpSocket->IsConnected()))
	{
		// we are uploading (or at least allow uploading) but currently no socket
		return max(CEMSocket::GetTimeOut(), GetPeerCacheSocketUploadTimeout());
	}
	else if (client && client->m_pPCUpSocket && client->m_pPCUpSocket->IsConnected())
	{
		// we have an uploading PC socket, but that socket is not used (nor can it be closed)
		return max(CEMSocket::GetTimeOut(), client->m_pPCUpSocket->GetTimeOut());
	}
	else if (client && client->m_pPCDownSocket && client->m_pPCDownSocket->IsConnected())
	{
		// we have a downloading PC socket
		return max(CEMSocket::GetTimeOut(), client->m_pPCDownSocket->GetTimeOut());
	}
	else
		return CEMSocket::GetTimeOut();
}

bool CClientReqSocket::CheckTimeOut()
{
	if(m_nOnConnect == SS_Half)
	{
		//This socket is still in a half connection state.. Because of SP2, we don't know
		//if this socket is actually failing, or if this socket is just queued in SP2's new
		//protection queue. Therefore we give the socket a chance to either finally report
		//the connection error, or finally make it through SP2's new queued socket system..
		if (::GetTickCount() - timeout_timer > CEMSocket::GetTimeOut()*4){
			timeout_timer = ::GetTickCount();
			CString str;
			str.Format(_T("Timeout: State:%u"), m_nOnConnect);
			Disconnect(str);
			return true;
		}
		return false;
	}
	UINT uTimeout = GetTimeOut();
	if(client)
	{
		if (client->GetKadState() == KS_CONNECTED_BUDDY)
		{
			//We originally ignored the timeout here for buddies.
			//This was a stupid idea on my part. There is now a ping/pong system
			//for buddies. This ping/pong system now prevents timeouts.
			//This release will allow lowID clients with KadVersion 0 to remain connected.
			//But a soon future version needs to allow these older clients to time out to prevent dead connections from continuing.
			//JOHNTODO: Don't forget to remove backward support in a future release.
			if( client->GetKadVersion() == 0 )
				return false;
			uTimeout += MIN2MS(15);
		}
		if (client->GetChatState()!=MS_NONE)
		{
			//We extend the timeout time here to avoid people chatting from disconnecting to fast.
			uTimeout += CONNECTION_TIMEOUT;
		}
	}
	if (::GetTickCount() - timeout_timer > uTimeout){
		timeout_timer = ::GetTickCount();
		CString str;
		str.Format(_T("Timeout: State:%u"), m_nOnConnect);
		Disconnect(str);
		return true;
	}
	return false;
}

void CClientReqSocket::OnClose(int nErrorCode){
	ASSERT (theApp.listensocket->IsValidSocket(this));
	CEMSocket::OnClose(nErrorCode);

	LPCTSTR pszReason;
	CString* pstrReason = NULL;
	if (nErrorCode == 0)
		pszReason = _T("Close");
	else if (thePrefs.GetVerbose()){
		pstrReason = new CString;
		*pstrReason = GetErrorMessage(nErrorCode, 1);
		pszReason = *pstrReason;
	}
	else
		pszReason = NULL;
	Disconnect(pszReason);
	delete pstrReason;
}

void CClientReqSocket::Disconnect(LPCTSTR pszReason){
	AsyncSelect(0);
	byConnected = ES_DISCONNECTED;
	if (!client)
		Safe_Delete();
	else
		if(client->Disconnected(pszReason, true)){
			CUpDownClient* temp = client;
			client->socket = NULL;
			client = NULL;
			delete temp;
			Safe_Delete();
		}
		else{
			client = NULL;
			Safe_Delete();
		}
};

void CClientReqSocket::Delete_Timed(){
// it seems that MFC Sockets call socketfunctions after they are deleted, even if the socket is closed
// and select(0) is set. So we need to wait some time to make sure this doesn't happens
	if (::GetTickCount() - deltimer > 10000)
		delete this;
}

void CClientReqSocket::Safe_Delete()
{
	ASSERT (theApp.listensocket->IsValidSocket(this));
	AsyncSelect(0);
	deltimer = ::GetTickCount();
	if (m_SocketData.hSocket != INVALID_SOCKET) // deadlake PROXYSUPPORT - changed to AsyncSocketEx
		ShutDown(SD_BOTH);
	if (client)
		client->socket = 0;
	client = 0;
	byConnected = ES_DISCONNECTED;
	deletethis = true;
}

bool CClientReqSocket::ProcessPacket(char* packet, uint32 size, UINT opcode)
{
	try
	{
		try
		{
			if (!client && opcode != OP_HELLO)
			{
				theStats.AddDownDataOverheadOther(size);
				throw GetResString(IDS_ERR_NOHELLO);
			}
			else if (client && opcode != OP_HELLO && opcode != OP_HELLOANSWER)
				client->CheckHandshakeFinished(OP_EDONKEYPROT, opcode);
			switch(opcode)
			{
				case OP_HELLOANSWER:
				{
					theStats.AddDownDataOverheadOther(size);
					client->ProcessHelloAnswer(packet,size);
					if (thePrefs.GetDebugClientTCPLevel() > 0){
						DebugRecv("OP_HelloAnswer", client);
						Debug(_T("  %s\n"), client->DbgGetHelloInfo());
					}

					// start secure identification, if
					//  - we have received OP_EMULEINFO and OP_HELLOANSWER (old eMule)
					//	- we have received eMule-OP_HELLOANSWER (new eMule)
					if (client->GetInfoPacketsReceived() == IP_BOTH)
						client->InfoPacketsReceived();

					if (client)
					{
						client->ConnectionEstablished();
						theApp.emuledlg->transferwnd->clientlistctrl.RefreshClient(client);
					}
					break;
				}
				case OP_HELLO:
				{
					theStats.AddDownDataOverheadOther(size);
					bool bNewClient = !client;
					if (bNewClient)
					{
						// create new client to save standart informations
						client = new CUpDownClient(this);
					}

					bool bIsMuleHello = false;
#ifndef _DEBUG
					try
#endif
					{
						bIsMuleHello = client->ProcessHelloPacket(packet,size);
					}
#ifndef _DEBUG
					catch(...)
					{
						if (bNewClient)
						{
							// Don't let CUpDownClient::Disconnected be processed for a client which is not in the list of clients.
							delete client;
							client = NULL;
						}
						throw;
					}
#endif

					if (thePrefs.GetDebugClientTCPLevel() > 0){
						DebugRecv("OP_Hello", client);
						Debug(_T("  %s\n"), client->DbgGetHelloInfo());
					}

					// now we check if we know this client already. if yes this socket will
					// be attached to the known client, the new client will be deleted
					// and the var. "client" will point to the known client.
					// if not we keep our new-constructed client ;)
					if (theApp.clientlist->AttachToAlreadyKnown(&client,this))
					{
						// update the old client informations
						bIsMuleHello = client->ProcessHelloPacket(packet,size);
					}
					else 
					{
						theApp.clientlist->AddClient(client);
						client->SetCommentDirty();
					}
					theApp.emuledlg->transferwnd->clientlistctrl.RefreshClient(client);

					// send a response packet with standart informations
					if (client->GetHashType() == SO_EMULE && !bIsMuleHello)
						client->SendMuleInfoPacket(false);
					client->SendHelloAnswer();
					if (client)
						client->ConnectionEstablished();

					// TODO: How does ConnectionEstablished() delete this client object????
					ASSERT( client );