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ModSecurity 2.5

You're reading from   ModSecurity 2.5 Prevent web application hacking with this easy to use guide

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Product type Paperback
Published in Nov 2009
Publisher Packt
ISBN-13 9781847194749
Length 280 pages
Edition 1st Edition
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Toc

Table of Contents (17) Chapters Close

ModSecurity 2.5
Credits
About the Author
About the Reviewers
1. Preface
1. Installation and Configuration FREE CHAPTER 2. Writing Rules 3. Performance 4. Audit Logging 5. Virtual Patching 6. Blocking Common Attacks 7. Chroot Jails 8. REMO 9. Protecting a Web Application Directives and Variables Regular Expressions Index

Simple string matching


You may ask if there isn't a way to match a string that ends with a certain other sub-string, without having to bother with escaping dots and putting dollar signs at the ends of lines. There is actually an operator that does just that—it's called @endsWith. This operator returns true if the targeted value ends with the specified string. If, as in the example above, we wanted to block remote hosts from microsoft.com, we could do it by using @endsWith in the following manner:

SecRule REMOTE_HOST "@endsWith .microsoft.com" deny

If we wanted to negate the above rule, and instead block any domain that is not from Microsoft, we could have done it in the following way:

SecRule REMOTE_HOST "!@endsWith .microsoft.com" deny

It is good practice to use simple string matching whenever you don't need to utilize the power of regular expressions, as it is very much easier to get a regular expression wrong than it is to get unexpected results with simple string matching.

The following...

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