Server security is not something that should be ignored. If an attacker gets on to your servers, do you know what they changed? Sure you’ve removed the gigabytes of malware with a virus scanner and manually cleaned up countless directories of illegal software, but is that all they left behind? Did they modify any of your important files, such as ‘su’ or ‘cp’ or ‘rm’? How would you know this? One answer is the Open Source project Tripwire. This tutorial will cover how to install, configure and maintain Tripwire on a Fedora 11 machine. This tutorial should be easily translatable to RedHat and CentOS 5.x with few (if any modifications) and to other Linux distributions with only minor changes.
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Archive for July, 2009
Regular Expressions
Jul 18
In programming, you will often want to match a pattern of text against a string or file. This can be helpful to do everything from validating runtime arguments to processing data during execution. Regular Expressions (or regex for short) provide you with the syntax to be able to do everything from very simple to very complex pattern matching in both Unix/Linux commands and in programming.
There are many different flavors of regex. Each programming language uses slight variations on the syntax, and each also has its own different shortcuts. The most commonly taught and documented regular expressions are Perl or Perl-compatible regex. Perl compatible regular expressions (PCRE) are used in .NET, Java, Ruby, Python, and many more languages. Again, each language has its own variation, so you’ll need to find the exact syntax for your particular language. All of those will be very close to the Perl regex I’ll document here.
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This is a short series on how to create a PHP SOAP based web service and WSDLs. We will start with setting up the developer environment, move on to a simple “Hello World” example and then move through a few examples of increasing complexity. Hopefully after this is done we can expand on the examples to create a web service as simple or as complex as we want. We will also build a simple client interface for each service to demonstrate how to access the new web service.