Limiting JavaScript Access to Other Websites

Security should always be the priority of every developer no matter what their programming language they are working on. But security has been on the special focus for JavaScript developers because of the security flaws reported on JavaScript and other Ajax based applications.

Although the client side is always susceptible to different type of attacks, none of the client side programming languages have the same trouble compared to JavaScript. You can blame the openness of the programming language in terms of development for its insecurity but this is the sole reason why Ajax has become so popular in just a short amount of time.

One of the security measures a developer could implement in their Ajax based application is restricting access of other websites. Because of the client side beauty of JavaScript, anyone that could access the website has the potential to ask for data even without authorization. At the same time, developers should also restrict access of their JavaScript application to different websites because they might open up to malicious websites.

There are two ways in limiting access of JavaScript library to other websites: the JavaScript option and the .htaccess option. Each option has advantage and disadvantages that developers should highly consider.

The JavaScript Option

The easiest way in restricting your JavaScript in accessing other websites is through JavaScript. With this option you are instructing the client side not to get its source on other websites. The advantage about this option is that developers would not have to deal with the server side and block other websites right from the start. This type of security measure could be implemented in almost any JavaScript and Ajax based application.

The disadvantage of this option is based on the fact that it’s still a JavaScript tool. That means hackers and other malicious websites could still overcome the restrictions provided by this screening tool. They can still use other sources in order to infiltrate the system. But this is very useful for relatively simpler websites since you are just pointing which websites that should be access by the website.

The .htaccess Option

Another option – rare but very effective is to restrict access right from the server end of the application. The .htaccess option will let developers make some changes in the application in terms of selecting the right source for the server side. Instead of changing the simple client side setting, .htaccess option prevents any intrusion to the client side.

Although the advantage for security of .htaccess is already there, few developers opted to use this option. The reason for that is the difficulty in integrating server side security for client side. Although everything will be secured, the application will be a lot slower since the server side will have to process everything.

This option is highly recommended for the enterprise wherein developers know the hardware and the software that runs in their clients’ gadgets. Using this function could be very difficult if the user will not have the processing power to process server side functions of JavaScript.