Using ISAPI rewrite to implement IIS picture anti-theft chain scheme

An ISAPI server extension is a DLL that can be loaded and invoked by an HTTP server. Internet Server Extensions, also known as Internet server Applications (ISA), are used to enhance the capabilities of servers that conform to Internet Server APIs (ISAPI). ISA is invoked through a browser application and provides similar functionality to a Common Gateway Interface (CGI) application.

Benefits of ISAPI Server Extensions

Users can fill out the form and then click the Submit button to send the data to the WEB server and invoke Isa,isa to process the information to provide custom content or to store the information in the database. Web server Extensions can use the information in a database to dynamically generate a Web page and then send it to a client computer for display. Applications can add additional customization features using HTTP and HTML and provide data to clients.

Server Extensions and filters run in the process space of the WEB server, providing an effective means of extending the functionality of the server.

What are the similarities and differences between ISAPI and CGI?

ISAPI Server Extensions provide an alternative to Common Gateway Interface (CGI) applications that use Internet servers. Unlike a CGI application, ISA runs in the same address space as the HTTP server, and can access all resources that can be used by the HTTP server. ISA has a lower overhead than CGI applications because they do not require the creation of other processes, nor do they perform traffic that needs to cross the process boundary, which can be time-consuming. If memory is required by another process, the extension and filter DLL may be uninstalled.

In order to realize the picture anti-theft chain, according to the data collected on the network plus their own practice, finally realized the image of IIS under the Anti-Theft chain function.

Implementation steps:

1. Download a free version of the ISAPI rewrite software provided by the more famous www.helicontech.com (although there are some functional limitations on the free version, the chain is sufficient):

Http://www.isapirewrite.com/download/isapi_rwl_x86_0072.msi

2. Set the Software installation directory of the IIS_WGP group read and Write permissions (important, if not set up after the installation of your site will be directly service unavailable, inaccessible).

To set the method:

If your installation directory is D:\Program files\helicon\isapi_rewrite (the default installation directory is \program Files\helicon\isapi_rewrite, we can build it first), right click Isapi_ Rewrite, select-> "Security"-> "Add"-> "advanced"-> "Find Now", find a IIS_WGP, double-click Add, OK. Then select the Group and click "Full Control" to have read and write access.

3. Install the software (the software restarts IIS during the installation), install directory Select the directory that has the right permissions in the previous step, open the Internet Information Service in the Control Panel after the installation, and open the Properties dialog box of the Web site with an "ISAPI filter", click "Add", "Filter Name" Casually fill out a good understanding of the name can be, "executable" Item click "Browse", select just installed the Isapi_rewrite installation directory of Isapi_rewrite.dll, OK. Restart IIS.

4. Modify the Httpd.ini file in the installation directory (if this file is read only), remove "Read Only" and then modify it.

Add to:

Rewritecond Host: ^ (. +) $

Rewritecond Referer: ^ (?!) http://\\1.*). *$

Rewritecond Referer: ^ (?!) Http://.*\.baidu\.com|. *\.google\.com|. *googlebot\.com|. *\.abc\.net). *). *$