Flyer For Maemo: Flex Security Demystified

felipebzr — Fri, 02 May 2008 16:38:39 +0300

Hello readers,

It's my first time blogging at Forum Nokia Blogs. I am very grateful for use this tool to share my experiments and get in touch with Nokia community.

Seven years ago I started developing Flash content for web and cd-rom but along the evolution of the Flash technology I went to the world of mobile devices. Long short story... Luck of mine!

Last month I received a N810 from Forum Nokia for testing purposes. I really enjoyed to play chess and start the porting of Flyer Framework.

Flyer Framework is an open source project to extend browsing features and mobile technologies. Flyer was primarily built to extend mobile technologies features, especially Flash Lite but along the development We’ve discovered the truly power of the platform.

Flyer Framework runs on almost any OS (Symbian, Linux, Windows, Mac OS) that supports both Flash Player and Python.

While I was working in the porting process of the Flyer engine for Maemo I found an interesting challenge... overcome the flash player security allowing calls between a local python server (flyer engine) and the flash player (web content).

Like Flash Lite 3, the Flash Player plugin embedded on Maemo has built-in security restrictions that prevents cross-domain access. If you are planning to implement and use your own socket server or if you are accessing anything remote from a local file, for security, by default Flash Player does not allow an application to access a remote data source from a domain other than the domain from which the application was served. So you have to put a crossdomain.xml file on the server you are accessing.

A crossdomain.xml file is an XML file that provides a way for a server to indicate that its data and documents are available to SWF files served from certain domains, or from all domains. The crossdomain.xml file must be in the web root of the server that the Flex application is contacting.

You can also check out an article on Forum Nokia Wiki explaining how to archieve this: How to create a Socket Server in Python. To get an in-depth overview of the flash player security model, check out the Developer Connection article: Creating more secure SWF web applications.

Felipe Andrade's Forum Nokia Blog

Flyer For Maemo: Flex Security Demystified