Beginning PHP for someone interested in Security

I'd like to learn PHP specifically for dealing with security vulnerabilities开发者_开发知识库/exploits.

Could someone recommend a book?

I don't know if I need to learn HTML/CSS/XML/XHTML etc, do I have to learn those too? I don't really plan on designing websites, could anyone help me with this? :P

You could have a look at "Essential PHP Security" by Chris Shiflett (http://phpsecurity.org/). I found it very useful when learning PHP.

To answer the second part of your question, although you don't have to be a HTML/CSS/XML/XHTML Guru, knowing the fundamentals is absolutely important. I believe, no developer will be asked to concentrate and code 100% on the server side logic alone, eg if you want to create AJAX web application the knowledge of XHTML and JavaScript becomes necessary. Knowing XML will also be of prime importance when dealing with data over the internet through web services.

So yes knowing a little HTML/CSS/XML/XHTML is absa-freaking-loutely important.

#1 rule, do not trust anything coming from the user.

Take a look at the Zend PHP 5 Certification Study Guide. It covers everything from PHP basics, through MySQL, and even into advanced OOP Classes. It even has a chapter on PHP Security. I'm currently using this for teaching my graduate-level PHP class.