peercachefinder.cpp

电驴的源代码

}

bool CPeerCacheFinder::IsClientPCCompatible(uint32 dwTagVersionInfo, uint16 nClientSoft){
	return IsClientPCCompatible(CClientVersionInfo(dwTagVersionInfo, nClientSoft));
}

bool CPeerCacheFinder::IsClientPCCompatible(const CClientVersionInfo& cviToCheck){
	CSingleLock lock(&m_SettingsMutex, TRUE);
	for (int i = 0; i != liAllowedVersions.GetSize(); i++){
		if (cviToCheck < liAllowedVersions[i])
			return false;
	}
	for (int i = 0; i != liBannedVersions.GetSize(); i++){
		if (cviToCheck == liBannedVersions[i])
			return false;
	}
	return true;
}

void CPeerCacheFinder::DownloadAttemptFailed(){
	m_nFailedDownloads++;
	if(m_nDownloadAttempts > 20 && m_nFailedDownloads > 0){
		DEBUG_ONLY(AddDebugLogLine(DLP_LOW, false, _T("PeerCache fail value: %0.2f"), (float)(m_nDownloadAttempts/m_nFailedDownloads)));
		if ( (float)(m_nDownloadAttempts/m_nFailedDownloads) < (float)2)
			AddDebugLogLine(DLP_LOW, false, _T("PeerCache fail value too high, disabling cache downloads"));
	}
}

///////////////////////////////////////////////////////////////////////////////////////
/// CPCValditeThread

IMPLEMENT_DYNCREATE(CPCValditeThread, CWinThread)

CPCValditeThread::CPCValditeThread()
{
}

CPCValditeThread::~CPCValditeThread()
{
}

BOOL CPCValditeThread::InitInstance()
{
	DbgSetThreadName("PCValditeThread");
	InitThreadLocale();
	return TRUE;
}

BOOL CPCValditeThread::Run(){
	if (theApp.emuledlg != NULL && theApp.emuledlg->IsRunning()){
		if (Valdite()){
			m_pOwner->m_bValdited = true;
			m_pOwner->m_nPCPort = m_nPCPort;
			if (m_pOwner->m_PCStatus == PCS_VALDITING){
				DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: Valditing .p2pinfo succeeded")));
				DEBUG_ONLY(theApp.QueueLogLine(false, GetResString(IDS_PEERCACHE_ENABLED)));
				m_pOwner->m_PCStatus = PCS_READY;
			}
			else
				ASSERT ( false );
		}
		else{
			m_pOwner->m_bValdited = false;
			m_pOwner->m_PCStatus = PCS_NOTVERIFIED;
			m_pOwner->m_nPCPort = 0;
		}
	}
	return 0;
}

void CPCValditeThread::SetValues(CPeerCacheFinder* in_pOwner, uint32 dwPCIP, uint32 dwMyIP){
	m_dwPCIP = dwPCIP;
	m_dwMyIP = dwMyIP;
	m_pOwner = in_pOwner;
}

bool CPCValditeThread::Valdite(){
	ASSERT ( m_dwPCIP != 0 );
	ASSERT ( m_dwMyIP != 0 );

	CInternetSession session;
	CInternetFile* file = NULL;
	for (int i = 0; i != ARRSIZE(anPeerCachPorts); i++){
		try
		{
			// try to connect to the URL
			CString strURL;
			strURL.Format(_T("http://%s:%u/.p2pinfo"), ipstr(m_dwPCIP), anPeerCachPorts[i]);
			file = (CInternetFile*)session.OpenURL(strURL);
			m_nPCPort = anPeerCachPorts[i];
			break;
		}
		catch (CInternetException* m_pException){
			// set file to NULL if there's an error
			file = NULL;
			m_pException->Delete();
			DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: Failed to retrieve .p2pinfo file on Port %u"),anPeerCachPorts[i]));
			if (i == (ARRSIZE(anPeerCachPorts)-1)){ // was last try
				DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: Failed to retrieve .p2pinfo file, cache disabled"),anPeerCachPorts[i]));
				return false;
			}
		}
	}
	ASSERT( file != NULL );
	// TODO: This will work successfully only for very small files which were received completely right at the
	// time the 'GetLength' function is called. -> Use a polling loop which reads everything up to get bytes
	// specified in 'Content-Length' or some other appropriate limit in case 'Content-Length' is missing.
	uint32 nIFileSize = file->GetLength();
	ASSERT (nIFileSize > SIGNATURELENGTH);

	if (file && nIFileSize > SIGNATURELENGTH){
		// read content
		CArray<uint32, uint32> adwCacheIPs;
		CStringAArray astrIPRanges;
		CStringA strLine;
		bool bContentCheckFailed = false;

		UINT uContentSize = nIFileSize - SIGNATURELENGTH;
		char* pcContent = new char[uContentSize + 1];
		if (file->Read(pcContent, uContentSize) != uContentSize)
			DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: Failed to read p2pinfo file content")));
		pcContent[uContentSize] = '\0';

		//----------- CHECKING .P2PINFO CONTENT
		// NOTE: 'pcContent' gets destroyed with 'strtok' !
		LPSTR pszLine = strtok(pcContent, "\r\n");
		while (pszLine && !bContentCheckFailed)
		{
			strLine = pszLine;
			int posSeperator = strLine.Find('=',1);
			if ( posSeperator != -1 && strLine.GetLength() - posSeperator > 1)
			{
				CStringA strTopic = strLine.Left(posSeperator).Trim();
				CStringA strContent = strLine.Mid(posSeperator+1).Trim();

				//DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: Current line to be processed: %hs"),strLine);

				///////***** CacheIP
				if (strTopic == "CacheIP"){
					adwCacheIPs.Add(inet_addr(strContent));
				}
				///////***** ClientIPRange
				else if (strTopic == "ClientIPRange"){
					astrIPRanges.Add(strContent);
				}
				///////***** ExpireDate
				else if (strTopic == "ExpireDate"){
					bool bDateCheckFailed = true;

					if (strContent.GetLength() == 8){
						uint32 nYear =  atol(strContent.Mid(0,4));
						uint32 nMonth = atol(strContent.Mid(4,2));
						uint32 nDay = atol(strContent.Mid(6,2));
						if (nYear <= 3000 && nMonth <= 12 && nDay <= 31){
							CTime timeExpireDate(nYear, nMonth, nDay, 0, 0, 0);
							if (timeExpireDate >= CTime::GetCurrentTime())
								bDateCheckFailed = false;	// check passed
						}
					}
					if (bDateCheckFailed){
						bContentCheckFailed = true;
						DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: ExpireDate check failed. Expiring date: %hs"),strContent));
					}
				}
				///////***** EnableED2K
				else if (strTopic == "EnableED2K"){
					if (atol(strContent) != 1){
						bContentCheckFailed = true;
						DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: EnableED2K check failed. Value: %hs"),strContent));
					}
				}
				else{
					DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: Unused content tag for validity check: %hs"),strLine));
				}

			}

			pszLine = strtok(NULL, "\r\n");
		}
		// finish the CacheIP check
		bool bIPRangeCheckFailed = true;
		for (int i = 0; i != adwCacheIPs.GetCount(); i++){
			if(adwCacheIPs[i] == m_dwPCIP){
				bIPRangeCheckFailed = false;
				break;
			}
		}
		if (bIPRangeCheckFailed){
			bContentCheckFailed = true;
			DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: CacheIP check failed.")));
		}
		// finish the RangeChack
		bool bIPCheckFailed = true;
		for (int i = 0; i != astrIPRanges.GetCount(); i++){ 
			CStringA strCurRange = astrIPRanges[i];
			int posContentSeperator = strCurRange.Find('-',7);
			if ( !(posContentSeperator == -1 || strCurRange.GetLength() - posContentSeperator <= 7) ){
				uint32 dwIPRangeStart = inet_addr(strCurRange.Left(posContentSeperator).Trim());
				uint32 dwIPRangeEnd = inet_addr(strCurRange.Mid(posContentSeperator+1).Trim());
				if (dwIPRangeStart != INADDR_NONE || dwIPRangeEnd != INADDR_NONE){
					if (ntohl(dwIPRangeStart) <= ntohl(m_dwMyIP) && ntohl(dwIPRangeEnd) >= ntohl(m_dwMyIP))
						bIPCheckFailed = false; // check passed	
				}
			}
		}
		if (bIPCheckFailed){
			bContentCheckFailed = true;
			DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: ClientIPRange check failed. my IP: %s"), ipstr(m_dwMyIP)));
		}

		//----------- CHECKING SPECIAL HEADERS CONTENT
		char achBuffer[3072]; // 3KB should be enough for headers
		DWORD nBufferSize = sizeof(achBuffer);
		if( !bContentCheckFailed && HttpQueryInfo(*file, HTTP_QUERY_RAW_HEADERS_CRLF, achBuffer, &nBufferSize, NULL) ){
			CStringA strHeaders = achBuffer;
			int nHeaderPos = 0;
			CStringA strCurHeader = strHeaders.Tokenize("\r\n",nHeaderPos);
			while (!strCurHeader.IsEmpty())
			{
				int posSeperator = strCurHeader.Find(':',1);
				if ( posSeperator != -1 && strCurHeader.GetLength() - posSeperator > 1)
				{
					CStringA strTopic = strCurHeader.Left(posSeperator).Trim();
					CStringA strContent = strCurHeader.Mid(posSeperator+1).Trim();

					DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: Current Header to be processed: %hs"),strCurHeader));
					///////***** X-eMule-Require-Version
					if (strTopic == "X-eMule-Require-Version"){
						int curPos= 0;
						CString strPCEncodedVersion(strContent);
						CString strVersion = strPCEncodedVersion.Tokenize(_T(" "),curPos);
						while (!strVersion.IsEmpty())
						{
							m_pOwner->AddAllowedVersion(CClientVersionInfo(strVersion));
							strVersion = strPCEncodedVersion.Tokenize(_T(" "),curPos);
						}
					} 
					///////***** X-eMule-Reject-Version
					else if (strTopic == "X-eMule-Reject-Version"){
						int curPos= 0;
						CString strPCEncodedVersion(strContent);
						CString strVersion = strPCEncodedVersion.Tokenize(_T(" "),curPos);
						while (!strVersion.IsEmpty())
						{
							m_pOwner->AddBannedVersion(CClientVersionInfo(strVersion));
							strVersion = strPCEncodedVersion.Tokenize(_T(" "),curPos);
						}
					}
				}
				strCurHeader = strHeaders.Tokenize("\r\n",nHeaderPos);
			}
			///////***** Own version check
			if (!m_pOwner->IsClientPCCompatible(CClientVersionInfo(VERSION_MJR, VERSION_MIN, VERSION_UPDATE, VERSION_BUILD, SO_EMULE))){
				bContentCheckFailed = true;
				DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: Current Version not allowed to use this PC-Server, please update")));
			}
		}
		else if (!bContentCheckFailed)
			DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache Error: Failed to retrieve headers, Errornumber %s"),GetErrorMessage(GetLastError()) ));


		//----------- CHECKING .P2PINFO SIGNATURE
		bool bSignatureCheckResult = false;
		if (!bContentCheckFailed){
			uchar* pachCompleteFile = new uchar[nIFileSize];
			file->SeekToBegin();
			if (file->Read(pachCompleteFile, nIFileSize) != nIFileSize){
				ASSERT( false );
				bSignatureCheckResult = false;
			}
			else{
				using namespace CryptoPP;
				Integer e, m, n;
				e = 3;
				n.Decode(achVerify_Key, ARRSIZE(achVerify_Key));

				uchar aucSignature[SIGNATURELENGTH];
				for (int i = 0; i != SIGNATURELENGTH; i++)
					aucSignature[(SIGNATURELENGTH-1)-i] = pachCompleteFile[(nIFileSize-SIGNATURELENGTH)+i];
				m.Decode(aucSignature, SIGNATURELENGTH);

				RSAFunction rsa;
				rsa.SetPublicExponent(e);
				rsa.SetModulus(n);
				Integer result = rsa.ApplyFunction(m);
				uchar aucResult[SIGNATURELENGTH];
				if(result.Encode(aucResult, SIGNATURELENGTH)){
					uchar aucHash1[16];
					for (int i = 0; i != 16; i++)
						aucHash1[i] = aucResult[(SIGNATURELENGTH-1)-i]; 
					bSignatureCheckResult = md4cmp(MD5Sum(pachCompleteFile, nIFileSize-SIGNATURELENGTH).GetRawHash(), aucHash1) == 0;
				}
			}
			delete[] pachCompleteFile;
			if (!bSignatureCheckResult)
				DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("PeerCache: Failed to verify PeerCache Server, not using it")));
		}

		delete[] pcContent;
		file->Close();
		delete file;
		return (bSignatureCheckResult && !bContentCheckFailed );
	}
	return false;
}

BEGIN_MESSAGE_MAP(CPCValditeThread, CWinThread)
END_MESSAGE_MAP()



IMPLEMENT_DYNCREATE(CPCReverseDnsThread, CWinThread)
BOOL CPCReverseDnsThread::InitInstance()
{
	ASSERT( m_hwndAsyncResult != NULL );
	ASSERT( m_dwIP != 0 );
	InitThreadLocale();

	memset(_acDNSBuffer, 0, sizeof _acDNSBuffer);
	CString strHostname = ReverseDnsLookup(m_dwIP);
	UINT uBufLen = 0;
	UINT uError = WSAEINVAL;
	if (!strHostname.IsEmpty())
	{
		CStringA strHostnameA(strHostname);
		uBufLen = sizeof(HOSTENT)		// 'hostent' structure
			+ sizeof(char*)		// h_aliases list + NUL entry
			+ sizeof(DWORD)*2		// h_addr_list + NUL entry
			+ strHostnameA.GetLength() + 1;
		if (uBufLen <= sizeof(_acDNSBuffer))
		{
			LPHOSTENT pHost = (LPHOSTENT)_acDNSBuffer;
			char* p = (char*)(pHost + 1);

			pHost->h_aliases = (char**)p;
			pHost->h_aliases[0] = (char*)NULL;
			p += sizeof(char*);

			pHost->h_addrtype = AF_INET;
			pHost->h_length = sizeof(DWORD);

			pHost->h_addr_list = (char**)p;
			pHost->h_addr_list[0] = (char*)m_dwIP;
			pHost->h_addr_list[1] = (char*)NULL;
			p += sizeof(char*)*2;

			pHost->h_name = p;
			strcpy(pHost->h_name, strHostnameA);
			p += strHostnameA.GetLength() + 1;

			ASSERT( p - _acDNSBuffer == uBufLen );
			uError = 0;
		}
		else
			uError = WSAENOBUFS;

		VERIFY( PostMessage(m_hwndAsyncResult, WM_PEERCHACHE_RESPONSE, 0, WSAMAKEASYNCREPLY(uBufLen, uError)) );
	}
	else
	{
		in_addr IPHost;
		// FIXME: Unable to resolve my own host - will always get the Windows Computer/Domainname. Dunno how to avoid this
		// cheap walk arround below by using another IP
		IPHost.s_addr = ntohl(ntohl(m_dwIP)+1);
		if (WSAAsyncGetHostByAddr(theApp.emuledlg->m_hWnd, WM_PEERCHACHE_RESPONSE, (const char*) &IPHost, sizeof(struct in_addr), AF_INET, _acDNSBuffer, sizeof(_acDNSBuffer)) == 0){
			if (thePrefs.GetVerbose())
				DEBUG_ONLY(theApp.QueueDebugLogLine(false, _T("DNS Reverse Lookup for own IP failed")));
		}	
	}
	return FALSE;
}