Jetbook hacking

[jgray]

Earlier tonight I installed Ubuntu in VirtualBox, as I don't currently have a Linux system running. I downloaded the current Jetbook firmware with the goal of seeing if anything could be modified or fonts added.

There are several files contained in the firmware Zip file. You are supposed to copy the contents of the archive to an SD card, insert into the Jetbook and then invoke the magic keypresses.

I'm certainly no Linux guru, but I did learn a little about what's going on with Jetbook firmware flashing. Files containing a boot loader, kernel and root filesystem are on the SD card. These files are used to boot the Jetbook prior to installing the new firmware image.

Before getting to the actual firmware, here are some interesting things from the root filesystem image used for flashing. Busybox is used (no surprise). The binary executables are "ELF 32-bit LSB executable, ARM, version 1, dynamically linked". It seems that the "uClibc" library is used. There is a shell running on "ttySMX0", which I understand is a serial port built in to the ARM chip (I'm not yet ready to disassemble my Jetbook to look for a connector).

All of this is very interesting and I thought if I could mount the actual firmware image, I might be able to do something with it. At this point, I am unable to proceed. The firmware image file is encrypted with AES. There is a shell script that calls a binary "aespipe", which decrypts the firmware image before flashing it.

Perhaps if I can modify the shell script so that it saves an unencrypted firmware image on the SD card, I might be able to continue. I'm currently on the ragged edge of my Linux skills with this, so it will take some head scratching. If any gurus care to pitch in, I would be happy to have the assistance.

[LuBiB]

Originally Posted by jgray

Earlier tonight I installed Ubuntu in VirtualBox, as I don't currently have a Linux system running. I downloaded the current Jetbook firmware with the goal of seeing if anything could be modified or fonts added.

There are several files contained in the firmware Zip file. You are supposed to copy the contents of the archive to an SD card, insert into the Jetbook and then invoke the magic keypresses.

I'm certainly no Linux guru, but I did learn a little about what's going on with Jetbook firmware flashing. Files containing a boot loader, kernel and root filesystem are on the SD card. These files are used to boot the Jetbook prior to installing the new firmware image.

Before getting to the actual firmware, here are some interesting things from the root filesystem image used for flashing. Busybox is used (no surprise). The binary executables are "ELF 32-bit LSB executable, ARM, version 1, dynamically linked". It seems that the "uClibc" library is used. There is a shell running on "ttySMX0", which I understand is a serial port built in to the ARM chip (I'm not yet ready to disassemble my Jetbook to look for a connector).

All of this is very interesting and I thought if I could mount the actual firmware image, I might be able to do something with it. At this point, I am unable to proceed. The firmware image file is encrypted with AES. There is a shell script that calls a binary "aespipe", which decrypts the firmware image before flashing it.

Perhaps if I can modify the shell script so that it saves an unencrypted firmware image on the SD card, I might be able to continue. I'm currently on the ragged edge of my Linux skills with this, so it will take some head scratching. If any gurus care to pitch in, I would be happy to have the assistance.

sounds pretty cool, if i was literate in any of the above lingo i would comment lol

so what can you add to the jetBook if you're able to manipulate the codes?

[jgray]

If I get anywhere, the first thing I want to do is add some fonts.

[LuBiB]

if you manage to do that let me know,, even though im pretty set with the ones already there it would never hurt to get some more

[wodin]

I'd like to see a full (or as full as possible with the hardware) implementation of FBReader.

[jgray]

I spent a bit more time looking into this today. It will not be so easy to decrypt the firmware so I can poke around in it. I don't want to do risky experiments with my only Jetbook and risk bricking it. I will have to give this more thought. I'll report back if I make any progress.

All I really want to do is add more fonts. I'll leave major firmware upgrades to the Ectaco folks.

[Schopenhauer]

The JetBook seems to be a hard one to hack.. Has there been any interesting progress since the last post 06-07-2009 ?

Happy Hacking

./Schoppy.

[infi]

Originally Posted by Schopenhauer

The JetBook seems to be a hard one to hack.. Has there been any interesting progress since the last post 06-07-2009 ?

A bit. Sobkas managed to extract the full firmware here:

https://www.mobileread.com/forums/showthread.php?t=65048

And we're talking about it (with admittedly not much progress on my part due to work) in this thread, including gr8npwrfl's work on an Android port, also:

https://www.mobileread.com/forums/sho...t=70909&page=2

[Schopenhauer]

I will just have to say... WOW!!!

I didnt see the thread with the extracted full firmware before!!

Could that information be usuable for someone that would like to try to adopt the OpenInkpot firmware to Jetbook/ Jetbook Lite ?

(Im asking because i just read "Nate the great´s" blogg entry here:
http://natesebooknews.com/2010/02/08...review-part-2/ )

How great wouldnt it be to have a open source supported firmware! If that would be successfull i think ectaco sooner or later would make their firmware opensource (since its already is quite stuffed with GPL stuff anyway?..)

The daily builds of the firmware support Coolreader and FBReader i hear.

I really wish I had the skills to do some work on this. If someone released the basics about how to understand how to make a alternative firmware flashing on the JetBook and how to boot the hardware, I guess a lot of linux people would join in right after that...

Would be a very interesting evolution for this unit and its future I think.

[gr8npwrfl]

I am waiting on some new development tools to arrive.

I have ordered a new MSO Oscilloscope so that I can look at both the digital and analogue signals in the JB.

Once I have finished the boot loader we will be able to install any Linux you want.

I am working on Android, it is Linux with some very extreme power management on top of a normal Linux kernel.

Open Inkpot is just another version of Linux.

The JB is based on a Strongarm processor. The hardware organization is very standard can only be done in certain fixed ways the chip is designed for.

I will keep updating as progress is made

[GhostHawk]

Been doing just a bit of light reading on Android. I can see why that would perhaps be the ultimate for Jetbook.

Best of luck, some of us are very interested in this project.

[Schopenhauer]

Holy Cow. You are certainly digging deep gr8npwrfl!
I just made a post in another thread that might concern jetbook hacking topics way out of your league then.

Still, gr8npwrfl (or anyone who knows), do you think this thing with OpenInkpot would work on Jetbook right now at this stage:

(People interested in this thread might probably want to look into this one also btw)
https://www.mobileread.com/forums/showthread.php?t=73679

"15:07 LunohoD:
someone with serial console should take our rootfs, chroot inside and try running applications. if it works, porting kernel is an optional task."

Not very likely that will work?...

Also, gr8npwrfl, Since the Jetbook Lite is slighly different (but simpler even), will the fantastic work you do function just as well on that unit?

I Look forward with great interest to see how things will work out, both with the boot loader, and with android.

[gr8npwrfl]

Yes we should be able to port Open Inkpot as soon as we get a bootloader working

[mazer]

Has there been any progress to either adding fonts to the firmware or getting a boot loader working? It seems some key players may have drifted away from working on the JBL, which is a shame for everyone else.

Android or Open Inkpot on this thing would be such a cool achievement.

Has anybody tried adding a ttf to the x11 folder that contains the Arial and Verdana ttfs?

I'm going to email Ectaco about adding a user font folder that could be referenced by the firmware. It is such a trivial feature to add, and yet it would make quite a few people even more thrilled with the JBL than they already are.

[jblitereader]

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