reverse engineering of Silverlight XAP files

Thursday, July 17, 2008

In my last post Michael Schwarz noticed that search engine spiders can theoretically index xap files.

Silverlight 2.0 creates a xap file where dll’s, images, videos and xml are included.

First step is to search in web for files with xap extension and download it. Then uncompress it with unzip algorithm ( eg rename to zip).

You will find a dll with the logic inside and several dll’s with librarys and a manifest file.

The you ca use (good old) reflector to disassemble the dll. The most interesting fact is that the original XAML file is included as resource.

You can then export ( save) the silder.xaml and open it with eg Expression Blend. Logic can be also taken from reflector which have the option to show it in VB.NET or C#.

Back to my beginning point. Till now I don’t know any search indexer which will do that.

6 Comments

I sure hope we can do something about this, and the Silverlight Spy app.

wisecarver - Thursday, July 17, 2008 9:08:57 PM

This is common for other files you run on websites, flash movies have the same problemm. I think however this should be changed if silverlight should become a big success in the enterprise world.

markvt - Friday, July 18, 2008 7:22:46 AM

I see it as a good thing. Hopefully, spiders will eventually catch on and content in SL can be indexed just like HTML so that you don't have to worry about killing your pagerank by putting content in a rich interface.

paul - Friday, July 18, 2008 10:51:15 AM

once Silverlight has a decent market share (both on the clients' and the producers' side), search engines will care. Before that, they won't.

Christian - Tuesday, July 22, 2008 1:20:49 PM

how to find the XAP file when u open silverlight 3.0 site

kk - Monday, December 7, 2009 1:11:22 PM

Reveres engineering of silverlight xap files.. Awful :)

weblogs.asp.net - Tuesday, June 14, 2011 1:46:35 PM

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