System and method for URL filtering in a firewall

• US 20060064469A1
• Filed: 09/23/2004
• Published: 03/23/2006
• Est. Priority Date: 09/23/2004
• Status: Abandoned Application

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Yarlagadda, Venkateswara Rao, Kumar, Krishna, Daftary, Kuntal, Balasubrahmaniyan, Jai
• Application Number:
  US10/948,474
• Publication Number:
  US 20060064469A1
• Time in Patent Office: Days
• US Class Current: 709/218
• CPC Class Codes: H04L 63/029 Firewall traversal, e.g. tunnelling or, creating pinholes
• CPC Class Codes: H04L 63/101 Access control lists [ACL]

Abstract

A method, system and a computer program product for managing requests for Uniform Resource Locators (URLs) in a firewall is provided. The firewall scans for requests for URLs and extracts the URLs from the requests. The firewall then checks for the URLs in an exclusive domains list. If the exclusive domains list allows the requested URLs, the firewall allows the URLs. In case the exclusive domains list disallows the requested URLs, the firewall blocks the requests for the URLs.

Claims

1. A method for managing a request for a Uniform Resource Locator (URL) in a firewall comprising:

scanning for the request;

extracting the URL from the request;

checking for access rights for the URL in an exclusive domains list stored in the firewall;

blocking the URL if the exclusive domains list disallows the URL; and

allowing the URL if the exclusive domains list allows the URL.

2. The method of claim 1 further comprising:

sending the URL to at least one URL filtering server; and

determining if the request for the URL is allowed or disallowed.

3. The method of claim 2 further comprising:

adding the response of the URL filtering server to an IP cache list.

4. The method of claim 2 further comprising:

requesting a webserver for the URL; and

buffering the response of the webserver till the URL filtering server determines if the URL is allowed or disallowed.

5. The method of claim 4 further comprising:

determining by the URL filtering server that the URL is disallowed;

removing the buffered response of the webserver; and

sending an access denied page to the requesting computer.

6. The method of claim 5 further comprising closing a connection between the requesting computer and the webserver that carries the request for the URL.

7. The method of claim 4 further comprising:

determining by the URL filtering server that the URL is allowed;

sending the buffered response of the webserver to the requesting computer.

8. The method of claim 7 wherein the sending the buffered response of the webserver to the requesting computer comprises sending by the firewall the buffered response of the webserver to the requesting computer.

9. The method of claim 2 further comprising:

determining if the URL filtering server is not operable; and

sending the URL to a secondary URL filtering server.

10. The method of claim 1 further comprising:

checking for access rights for the URL in an IP cache list stored in the firewall;

blocking the URL if the IP cache list disallows the URL; and

allowing the URL if the IP cache list allows the URL.

11. The method of claim 1 wherein the exclusive domains list comprises at least one of complete domain names and partial domain names.

12. A method for managing a request for a Uniform Resource Locator (URL) in a network, the network comprising at least one virtual network and at least one firewall, the method comprising:

providing at least one exclusive domain list corresponding to each virtual network in the at least one firewall;

scanning for the request;

extracting the URL from the request;

checking for access rights for the URL in the at least one exclusive domains list;

blocking the URL if the at least one exclusive domains list disallows the URL; and

allowing the URL if the at least one exclusive domains list allows the URL.

13. The method of claim 12 further comprising:

sending the URL to at least one URL filtering server; and

determining if the request for the URL is allowed or disallowed.

14. The method of claim 13 further comprising:

adding the response of the URL filtering server to an IP cache list.

15. The method of claim 13 further comprising:

requesting a webserver for the URL; and

buffering the response of the webserver till the URL filtering server determines if the URL is allowed or disallowed.

16. The method of claim 12 further comprising:

checking for access rights for the URL in an IP cache list stored in the firewall;

blocking the URL if the IP cache list disallows the URL; and

allowing the URL if the IP cache list allows the URL.

17. The method of claim 12 wherein the exclusive domains list comprises at least one of complete domain names and partial domain names.

18. A method for filtering URL in a firewall comprising:

sending through a firewall an HTTP request to a webserver;

creating a URL request;

sending the created URL request to a URL filtering server for determining if the URL request is acceptable or unacceptable; and

buffering a response from the webserver until the URL filtering server determines if the URL is acceptable or unacceptable.

19. A method for storing a URL in a firewall comprising:

sending through a firewall an HTTP request to a webserver;

creating a URL request;

determining if the URL request is acceptable or unacceptable; and

storing the URL acceptance or denial in the firewall.

20. A firewall for managing a request for a Uniform Resource Locator (URL) comprising:

a Hyper Text Transfer Protocol (HTTP) module for scanning the request and extracting the URL; and

at least one exclusive domains list for filtering the URL, the exclusive domains list storing access rights for URLs.

21. The firewall of claim 20 further comprising:

a URL filtering client for sending the URL to at least one URL filtering server; and

an IP cache list for storing responses of the at least one URL filtering server.

22. A system for managing a request for a Uniform Resource Locator (URL) comprising:

a firewall for filtering the request for the URL, the firewall further comprising at least one exclusive domains list for filtering the request for the URL, the exclusive domains list storing access rights for URLs;

at least one URL filtering server for defining the filtering of the URL; and

a webserver for serving the request for the URL.

23. An apparatus for managing a request for a Uniform Resource Locator (URL) in a firewall comprising:

a processor;

a machine-readable medium including instructions executable by the processor for;

scanning for the request;

extracting the URL from the request; and

blocking the URL if the exclusive domains list disallows the URL; and

allowing the URL if the exclusive domains list allows the URL.

24. A machine-readable medium in a firewall having stored thereon instructions for:

scanning for a request for a Uniform Resource Locator (URL);

extracting the URL from the request; and

blocking the URL if the exclusive domains list disallows the URL; and

allowing the URL if the exclusive domains list allows the URL.

25. A system for managing a request for a Uniform Resource Locator (URL) in a firewall comprising:

means for scanning for a request for a Uniform Resource Locator (URL);

means for extracting the URL from the request; and

means for blocking the URL if the exclusive domains list disallows the URL; and

means for allowing the URL if the exclusive domains list allows the URL.