App backup 12 hour hack-a-thon challenge failed, for now.

App backup challenge

I wrote an article earlier about Rafael Rivera’s 12 hour Hack-a-thon, it was my hope that he would succeed in his self made challenge, unforunately for us, he was not successful as yet, but has let us know the challenge timer may have expired but the task will still be worked on, perhaps by more individuals. I asked Rafael for a quote to add to the story and he said the following…

I wasn’t successful this time, but as Fuller once said: “There is no such thing as a failed experiment, only experiments with unexpected outcomes.“

His blog has been updated now and the following information has been added…

So what happened? I made some assumptions that weren’t in fact true. This left me poking, prodding, and fighting Windows Phone’s OMA Client Provisioning layer all night. (I totally get why the XDA Developers folks keep playing with this stuff now.)

Here are some technical notes in no real order:

My ARM7i compiled DLLs worked nicely. Hurray for miracles.

Using Samsung’s LaunchExe function was pretty simple, for bouncing out of Least Privileged Chamber (LPC).

Rapiconfig.exe, the configuration tool that executes provisioning XML, blows. By blows, I mean it’s poorly written and requires certain stars and planets to be aligned in a particular manner to work correctly. For example, I wasted hours trying to feed it valid XML to later learn from XDA’s Heathcliff74 that provisioning XML must be in Unicode (UTF-16). Never mind the actual encoding specified in the XML header or using a proper damn XML parser. Also, the attributes and elements are all case-sensitive. God only knows what would happen if you introduce a single blank line.

According to MSDN/Technet documentation for both WM6 and Windows Embedded Compact 7 – of which Windows Phone is supposedly built upon – the provisioning magic on the phone supports a parameter name of “SelfRegister”. This was supposed to tell the OS that I want to (COM) register my library. This should have then triggered a call into DllRegisterServer, executing my code. I tried this with both TCB signed and unsigned code to no avail. Maybe I screwed something up here? I suspect this was broken for valid security reasons.

My phone is very unstable. At times, simple things like COM registration were failing with security errors. And at one time I was able to deploy XAPs with my phone locked. Scary. Reboots fixed all these issues temporarily.

At least sleep depravation hasn’t dampened his spirit, If there is any further news on the homebrew app backup tool I will bring it to you.

You can find Rafael’s blog Here or follow @WithinRafael on twitter.

About bAN01TgAZ

Gary Jones has contributed 125 articles on this blog.

My name is Gary Jones. I am the News Editor on 1800PocketPC.com. I will try to bring all the Windows Phone news to you

• View all posts by bAN01TgAZ →
• Blog
• Twitter
• Facebook

More Windows Phone Apps :

Tagged as: app backup, Homebrew, rafael rivera, within windows