ipaddressfilter.h

VC实现的ISAPI过滤器

#if !defined(AFX_IPADDRESSFILTER_H__AC1B7F27_82E5_11D2_A28C_006067323266__INCLUDED_)
#define AFX_IPADDRESSFILTER_H__AC1B7F27_82E5_11D2_A28C_006067323266__INCLUDED_

// IPADDRESSFILTER.H - Header file for your Internet Server
//    IP Address Sample Filter

#include "resource.h"


// The maximum number of addresses we will cache.  If there will be a large number
// of simultaneous addresses, bump this value
#define MAX_CACHED_ADDRESSES 100

// The position after which we'll move a cache entry to the front of the list
#define LIST_REORDER_THRESHOLD 6

// The maximum length of an IP address
#define MAX_IP_ADDRESS 64

//  This is the name of the file that contains the ip addresses.
//  Wildcards can be used for the host part only (172.16.*.1 is not allowed).
//
//  The format of the file is:
//
//  127.*
//  172.16.1.6
//  172.16.2.*
//  172.16.*
//  
#define IP_LIST_FILE "c:\\winnt\\system32\\inetsrv\\ipaddressdb.txt"

// The html page showing access denied. 
#define NO_ACCESS "C:\\InetPub\\wwwroot\\NoAccess.htm"

// Constants
#define ISWHITE(ch)  ((ch) && ((ch) == ' ' || (ch) == '\t' || (ch) == '\n' || (ch) == '\r'))

// Cached ip address structure
typedef struct _IP_INFO
{
	LIST_ENTRY  ListEntry;  // Double linked list entry

	CHAR  achIPAddress[MAX_IP_ADDRESS];   // ip address

} IP_INFO, *PIP_INFO;

class CIPAddressFilter : public CHttpFilter
{
public:
	CIPAddressFilter();
	~CIPAddressFilter();

// Overrides
	// ClassWizard generated virtual function overrides
		// NOTE - the ClassWizard will add and remove member functions here.
		//    DO NOT EDIT what you see in these blocks of generated code !
	//{{AFX_VIRTUAL(CIPAddressFilter)
	public:
	virtual BOOL GetFilterVersion(PHTTP_FILTER_VERSION pVer);
	virtual DWORD OnUrlMap(CHttpFilterContext* pCtxt, PHTTP_FILTER_URL_MAP pMapInfo);
	//}}AFX_VIRTUAL

// Implementation
protected:
	BOOL Initialize();
	static BOOL ValidateIPAddress(const CHAR* pszIPAddress, OUT BOOL* pfValid);
	// Database routines
	BOOL InitializeIPAddressDatabase();
	static BOOL LookupIPAddressInDb(const CHAR* pszIPAddress, OUT BOOL* pfFound);
	VOID TerminateIPAddressDatabase();
	// Cache routines
	BOOL InitializeCache();
	static BOOL LookupIPAddressInCache(const CHAR* pszIPAddress, BOOL* pfFound);
	static BOOL AddIPAddressToCache(const CHAR* pszIPAddress);
	VOID TerminateCache();

protected:
	BOOL  m_fCacheInitialized;	// Indicates whether the cache is initialized
	
	static DWORD m_cCacheItems;						 // Number of items in the cache
	static CHAR* m_pszIPAddressFile;			 // Buffer for ip addresses database
	static LIST_ENTRY m_CacheListHead;		 // Circular double linked list of cached addresses
	static CRITICAL_SECTION m_csCacheLock; // Critical section protects cache list

	//{{AFX_MSG(CIPAddressFilter)
	//}}AFX_MSG
};

//{{AFX_INSERT_LOCATION}}
// Microsoft Developer Studio will insert additional declarations immediately before the previous line.

#endif // !defined(AFX_IPADDRESSFILTER_H__AC1B7F27_82E5_11D2_A28C_006067323266__INCLUDED)