Sony mylo com-2 rockbox help

[nelsontheunholy]

Hi guys

Been lurking here for a while but now I am looking for a little help.  I am wanting to open up the sony mylo com-2  it has really similar hardware to the Toshiba gigabeat s and the original zune 30.  From what I have been able to ascertain so far about the device and hardware is

i.mx31l arm 1136 532mhz cpu
128mb of ram
1gb nand flash
wifi bg chipset is made by samsung but what I have read up on it seems to suggest it also supports bluetooth 2.0
800x480 display
1.3mp camera
has a full hardware keyboard with backlighting that is controlled by a light sensor on the back of the display when the device is slid open.

As far as software goes it is built on a qtopia stack linux but has been crippled and won't run custom code and it also masks the filesystem.  It appears to be running redboot for a bootloader but sony never released there source for the bootloader so that might be a gpl violation in of itself.  I know a few people had done some work on  the gigabeat s which is very similar so wanted to see if I could get some help better understanding the firmware and if possible bypassing the key sig checking of the firmware so I could mod it to include perhaps some sort of command line utilities like busybox.  Any help or a nudge in the right direction would be helpful.  Sony abandoned this product they originally charged 300 bucks for and haven't released a firmware update in almost 2 years so most of the device api's that it uses to connect to yahoo or youtube have changed making the device nearly useless  still plays mp3 and movies but it could be so much more if it would just support a more open platform.  Rockbox would be really nice alternative to what it has now but if I could even figure out how to extract and dump the update.bin firmware files and view the contents I would have a better understanding on how to go about opening up the software.

[saratoga]

As far as software goes it is built on a qtopia stack linux but has been crippled and won't run custom code and it also masks the filesystem.  It appears to be running redboot for a bootloader but sony never released there source for the bootloader so that might be a gpl violation in of itself.  I know a few people had done some work on  the gigabeat s which is very similar so wanted to see if I could get some help better understanding the firmware and if possible bypassing the key sig checking of the firmware so I could mod it to include perhaps some sort of command line utilities like busybox. 

The gigabeat S is a Windows CE device.  If your player runs Linux, then theres probably not a lot in common with the Gigabeat S firmware.  How does the signature check on this device work?

[nelsontheunholy]

I think the signature checking works by checking for a signing key.  The update file is updat.bin and is about 64mb in size.  The only way to update the device is by using the on device updater to load an image from ms duo or download from the internet.  You can't actually view the file system or its contents.  Instead it uses a dropbox utility to move crap from internal storage to ms duo.  It hides the firmware partitions.  I am pretty sure it uses redboot for the bootloader but haven't found a way to put it in recovery mode or a bootloader mode.

[saratoga]

Why do you think there is a signature check then?

[nelsontheunholy]

I am pretty sure it encrypted but I could be wrong but I have not been able to dump the rom or decrypt the update package to see the structure of the file system. 
Post Merge: May 09, 2011, 12:13:59 AMcould just be a version check kinda deal too.  I could try changing it with a hex editor and see if it will let me go that route.