Sunday, October 28, 2012

UDS GTA04 Hacking

I'm sitting at the Bella Sky lobby bar while UDS people keep pouring in. I guess I have to start this UDS with some hacking (and a little beer)! I bootstrapped an Ubuntu armhf rootfs and coupled it with QtMoko's kernel already earlier after I received my GTA04 but it didn't boot right away so I had nothing to report. I wanted armhf so I chose QtMoko's 'experimental' Debian armhf rootfs + boot files as the reference to look at while working on the Ubuntu rootfs. I now went through again some of the configuration files, and voilĂ :

Now running apt-get install unity over SSH :) It will require OpenGL ES 2.0 hw acceleration to run, now that the support was integrated in Ubuntu 12.10. I will therefore need to tinker what kind of OMAP3 armhf binary blobs there are available, and what's again the situation with DDX driver as well. I always feel that the fun starts at this point for me, when I've the device booting and I can SSH in. That's why I'm happy the work from Golden Delicious GmbH and QtMoko helped me to get here...

Saturday, October 13, 2012

OpenPhoenux GTA04

Postman was on a kind mood yesterday. My OpenPhoenux GTA04 arrived! I had my newer Neo FreeRunner upgraded via the service from Golden Delicious.

First, something rare to behold in phones nowadays - Made in Bavaria:

As a sidenote, also rare now - my Nokia N9 is one of the last phones that had this:

It's sad that's now a thing of the past for both hardware assembly and software! But that's just a hint for new companies to step in.

But back to GTA04 - a quick boot to the pre-installed Debian w/ LXDE:

And then as a shortcut unpacked and booted into QtMoko (well, it's also Debian) instead to test that phone functionality also works - and it does:

Next up: brewing something of my own!

Saturday, October 06, 2012

Light-weight security, Grub2 password setup problems 1.99 vs 2.00

I believe I'm not the only one who thinks that use case oriented Grub2 documentation is hard to find, and a lot of the documentation is obsolete or wrong. My main cause for writing this blog post is a currently unanswered question regarding 2.00, but meanwhile it seems months have passed and still most 1.99 documentation is wrong as well, which might be interesting to some.

The aim is to prevent grub entries from being edited, while not restricting actual booting. This protection is meant for computers not having any confidential stuff, but just wanting to do some light weight security with the assumption that the computer isn't physically opened.

Common setup

You will obviously want to disable any automatically generated root access giving entries, by for example uncommenting GRUB_DISABLE_RECOVERY="true" in /etc/default/grub on Debian or Ubuntu. Also you would disable allowing any external boot devices to be used in BIOS/EFI/coreboot, which you would also have protected with a password. And that often means you need to also disable USB legacy support, since some BIOSes tend to offer all USB devices as bootable without password otherwise (note that I guess that could also cause problems accessing setup on desktop computers if your only keyboard is USB).


So to first fix the false instructions in various places - no, setting the superuser in 00_header as instructed is not enough. It might be, but does not apply if eg. old kernels are put into submenu (Ubuntu bug 718670, Fedora bug 836259). The protection from editing does not apply there. And if you remove all but one kernel so that there is no submenu, a submenu will be automatically created when there is a new kernel installed via security updates. I didn't need the submenu feature anyway, so I used to comment out the following lines in /etc/grub.d/10_linux:

  #if [ "$list" ] && ! $in_submenu; then
    #echo "submenu \"Previous Linux versions\" {"
#if $in_submenu; then
#  echo "}"

I hope that was useful. I can imagine it causing a couple of family battles if the commonly instructed setup was the only protection used and there's for example a case of two computer savvy siblings that are eager to get to each others' computers...

2.00 & The Question

The problem with 2.00 is that the superusers setup yields a non-bootable system, ie. password is required for booting. But Google wasn't smiling at me today! Terrible. Can you help me (and others) with 2.00? The aim would be to have a 1.99-like setup where superuser password protects all entries from editing, but booting is fine without any passwords.

Update: Thanks, problem solved, see comments! Find the following line in /etc/grub.d/10_linux:

      echo "menuentry '$(echo "$os" | grub_quote)' ${CLASS} \$menuentry_id_option 'gnulinux-simple-$boot_device_id' {" | sed "s/^/$submenu_indentation/"

And add --unrestricted there. Don't mix the line with the another menuentry line two lines earlier. The submenu problem doesn't exist anymore in 2.00.