System, method, and computer program product for applying a regular expression to content based on required strings of the regular expression

• US 8,522,199 B2
• Filed: 02/26/2010
• Issued: 08/27/2013
• Est. Priority Date: 02/26/2010
• Status: Active Grant

• Current Assignee: McAfee, LLC
• Original Assignee: McAfee, Inc. (McAfee, LLC)
• Inventors: Beveridge, David Neill, Cochin, Cedric
• Primary Examiner(s): Nguyen, Phillip H
• Application Number:
  US12/714,324
• Publication Number:
  US 20120311529A1
• Time in Patent Office: 1,278 Days
• Field of Search: 717/106, 717/107, 717/108
• US Class Current: 717/107
• CPC Class Codes: G06F 16/90344 by using string matching techniques

Abstract

A system, method, and computer program product are provided for applying a regular expression to content based on required strings of the regular expression. In use, all required strings included in a regular expression are identified, the required strings including strings required by the regular expression. Additionally, it is determined whether the required strings match content. Furthermore, the regular expression is applied to the content, based on the determination.

Claims

1. A computer program product embodied on a tangible computer readable medium, comprising:

computer code for identifying all required strings included in a regular expression, the required strings including strings required by the regular expression;

computer code for determining whether the required strings match content;

computer code for applying the regular expression to the content, based on the determination;

computer code for merging each of the required strings and its associated length into a separate template of code to generate a segment of code;

computer code for concatenating the generated segments of code in an order of the required strings; and

computer code for injecting the concatenated segment of code in a driver prior to a callout of the regular expression to form an updated driver.

2. The computer program product of claim 1, wherein the computer program product is operable such that the required strings are identified by parsing the regular expression.

3. The computer program product of claim 1, wherein the computer program product is operable such that the required strings are identified by removing optional strings from the regular expression.

4. The computer program product of claim 3, wherein the optional strings include wildcards.

5. The computer program product of claim 1, wherein the computer program product is operable such that the required strings are identified by removing quantity operators from the regular expression.

6. The computer program product of claim 1, wherein the computer program product is operable such that the required strings are identified by removing back references from the regular expression when the back references are not used by the regular expression.

7. The computer program product of claim 6, wherein the computer program product is operable such that the regular expression is validated in response to the removal of the back references, such that the determination of whether the required strings match the content is only performed in response to the validation of the regular expression.

8. The computer program product of claim 1, wherein the computer program product is operable such that the required strings are identified in response to a determination that each of the required strings exceeds a predetermined length.

9. The computer program product of claim 1, further comprising computer code for identifying a length of each of the required strings.

10. The computer program product of claim 1, wherein the template of code includes elimination code for automatically terminating execution of the updated driver in response a determination that a required string merged with the template of code does not match the content, such that application of the regular expression to the content is avoided.

11. The computer program product of claim 1, further comprising computer code for applying at least one of required strings to the content in an order in which the required strings exist in the regular expression, for determining whether the required strings match the content.

12. The computer program product of claim 11, further comprising computer code for avoiding applying remaining ones of the required strings in response to a determination that a last applied one of the required strings does not match the content.

13. The computer program product of claim 1, wherein the computer program product is operable such that the regular expression is not applied to the content, in response to a determination that at least one of the required strings does not match the content.

14. The computer program product of claim 1, wherein the computer program product is operable such that the regular expression is applied to the content, in response to a determination that all of the required strings match the content.

15. A method, comprising:

identifying all required strings included in a regular expression, the required strings including strings required by the regular expression, utilizing a processor;

determining whether the required strings match content;

applying the regular expression to the content, based on the determination;

merging each of the required strings and its associated length into a separate template of code to generate a segment of code;

concatenating the generated segment of code in an order of the required string; and

injecting the concatenated segment of code in a driver prior to a callout of the regular expression to form an updated driver.

16. A system, comprising:

a processor, wherein the system is configured for;

identifying all required strings included in a regular expression, the required strings including strings required by the regular expression,

determining whether the required strings match content,

applying the regular expression to the content, based on the determination,

merging each of the required strings and its associated length into a separate template of code to generate a segment of code;

concatenating the generated segment of code in an order of the required string; and

injecting the concatenated segment of code in a driver prior to a callout of the regular expression to form an updated driver.

17. The system of claim 16, wherein the processor is coupled to memory via a bus.