Freeing my tablet: Android hacking, software and hardware
thanassis.space
thanassis.space
>For the TL;DR crowd: I wanted to run a Debian chroot in my tablet;
I'm sad that there aren't more people looking to run a mainline kernel + Linux distro on their tablets. It's definitely possible but a lot more difficult.
[1] maruos.com
There is work in progress for sony camera on android (mine is too old): http://www.personal-view.com/faqs/sony-hack/hack-development
You have to register for a Mi account and a Miui forum account and then request unlocking privileges for it. This is apparently a manual process: approval can take anywhere from two days to several weeks. Having more internet points on their forum[1] may or may not speed up the process. Approved Mi accounts can unlock 1 device per 30 days.
Once you've got the unlocking privs, you can download a Windows (and only Windows) executable that performs the unlocking process (it comes bundled with the fastboot/adb executables). It checks that your phone is logged into the same Mi account as one part of a completely opaque validation.
The official documentation, as it were, says you need their "global development" OS running on the phone, but I'm pretty sure it worked with the non-development version, which is good because updating to development failed with a non-descript error.
Once I unlocked the phone -- using a friend's Mi account which had unlocking privs, unbeknownst to him since he never got the notification -- I had to install TWRP (the most popular alternate recovery image). The official versions did not work (either crashing or nonfunctional). After about a dozen recovery images from various file hosters -- exactly where I want to acquire core system software -- I stumbled on one that worked, albeit defaulting to Chinese.
I suppose the fact that I did not brick the device speaks to the robustness of Android's bootloader/recovery/system separation.
[1] A forum which goes to ridiculous lengths to feature these points. Points for replying, points for getting replies, bounties, etc etc. Users posting useful files restrict the link visibility to people who have answered in the thread, which leads to threads with hundreds or thousands of one-word "Thanks" posts, each taking up 200px of vertical space due to the amount of "badges" the forum has. It's insane. Is that a Chinese thing? Or just how the kids do it these days?
Torvalds' decision was extremely practical and has lead to huge gains for Linux users even if (ahem) not every company gives back.
In Fuchsia, they are even replacing Linux by their own micro-kernel, BSD licensed.
How much contributions has Sony given back to BSD from their PS4 BSD distribution?
FWIW: I, for sure, appreciate the GPL3 and copy-left licenses.
About companies using GPLv2 software in computers and devices and you being unable to change the software the computers run. In case you did not read the linked article, it is a very long story about someone trying to use Linux on a tablet that was shipped with Linux.
See for instance https://en.wikipedia.org/wiki/GNU_General_Public_License#Ver....
More like Qualcomm. They like this mess of partitions, not Google.
> I am NOT a bad guy!... I just want to remain in full control of my OWN hardware...
Yeah, they don't want to respect that. And if you care about that, your choices of hardware become pretty limited. Let alone if you want to have open drivers for key components like GPU and the rest. In practice, Google's Nexus devices tend to be one of the best choices (i.e. such as Nexus 5 and Nexus 7). Not sure what the situation with Pixels is.
Obviously a tutorial online shows at least a small fraction of demand for open hardware, but as you say, the choices become limited if you care about it, probably as a result of such a small number actually caring enough to vocalise/put money where their mouths are.
But this isn't really about attacking rights necessarily. Most of the time they simply cut costs. To make hardware respect freedom requires some extra effort, and the likes of Qualcomm and Asus simply don't care. It's easier for them to lock it up.
I fully agree, we're lucky PCs are open in that regard, I'd love hardware to be separated from software and we can do as we wish, but that's not what's being sold to us, or what the mass market they're targeting is demanding. They are creating and selling a product, not just hardware.
Edit: and again, I'm not saying it's right, definitely not, and certainly not saying don't kick up a fuss and show the companies what you want, just that buying an item that makes no claims to openness and just expecting it to be open "because", is naive.
Conversely, beyond consumer protection legislation you don't have any right to tell manufacturers what products they must sell and what the features of those products must be. If a manufacturer decides that the optimum solution for them is to lock down the system as they believe that's the best way to protect customers from their devices being subverted maliciously, that's for them to decide. If you don't agree, just don't buy the product.
I'm sure there will be pure-play hardware companies out there in the "non-PC component" space at some point, but at present most are making end-to-end products.
>Yeah, they don't want to respect that.
Honest question: if you were responsible for platform security, how would you tell apart the bad guys from the legitimate owner asserting control over their hardware? My imagination might be failing me, but I can't see a scenario where making it easy for the owner to get root doesn't also make it easier for malicious third parties to subversively add rootkits.
The only workable solution I could think of is to sell factory-rooted models for the advanced users and a locked-down version for everyone else, but I suspect the market is not large enough to support an additional SKU.
edit: fastboot oem unlock is also fairly reasonable compromise, when available, but I don't think many users would know what a unlocked padlock icon when booting means in any case, and would happily use the device
How about Google's hardware "dev switch?" Originally they hid it inside the Kensington lock, but now it's purely a software switch.
https://www.chromium.org/chromium-os/developer-information-f...
When the switch is on it also displays a scary warning for 30 seconds when the computer boots that "this software cannot be trusted."
I think this is a very important point that people tend to overlook. One that I've definitely stated to appreciate in recent years.
For a similar example, sometimes people talk about the cost of ownership of a PC. Whenever you bring that up, someone will mention how it's really cheap to build your own PC. And although they're technically correct, since it's really cheap to build your own PC, it usually means you're left on your own for maintaining it as well.
I can't shake the feeling that this case is similar. Although I certainly enjoy tinkering with stuff, I think there's a strong argument to be made for things that "just work", or things that can be easily hacked. I have a hard time imagining that the real cost of ownership of this device for the owner ended up being higher than if they had purchased a more open device.
With all of that being said, I found this to be a very interesting read, and I'm thankful that the author took the time to write up their experience.
Something I can install KDE Neon to?
I can reversibly root it?!
After looking for a while into various phones, I ended up getting a Sony Z3+ -- as it combines many things I want (water proof, memory card slot) with a pretty strong commitment from Sony:
http://developer.sonymobile.com/open-devices/
Ironically, I've yet to actually experiment with different roms and other software on my Sony phone, but there it is.
The code "protecting" the bootloader is good enough that it could be very, very difficult to unlock your bootloader without official support.
I feel this is a little bit different from the "zune drm hole" where you "buy" (rent) content, but might loose all access once the provider goes under/closes shop. (See also: the case of Amazon recalling copies of "1984" it had sold as an e-book without a proper license).
What if I buy it from eBay 5 years later?
unless you can pad your new image to get a hash colision and make the bootloading chain thinks it is a signed image. good luck with that.
https://play.google.com/store/apps/details?id=com.gnuroot.de...
I like having small devices, and I like Linux. My solution was to buy a small HP stream 11, and just put Linux on it. Not impressive technically, like the author's work on his tablet, but an easy way to get Linux on a $190 small device. I like to travel with my Linux stream: fully capable for work, using the web, and cheap enough that I don't worry about losing it.
It would have been fantastic if the tablet in the article had a locked bootloader, because I really want to learn how to unlock these bootloaders from scratch. I'm just not comfortable by downloading random binaries from questionable filelockers and loading them on my tablet, I want to know how they are produced so I can do it myself.
I'm reading everything I can find, but the information on this subject is very limited and consists most of "flash these files" and absolutely no informtion how they were created.
Does anyone have good resources on the process of unlocking bootloaders from scratch?
"Secure against physical access by all but extremely determined attackers" is worth aiming for. Even if it's just a measure against the resale of stolen devices.
https://wiki.debian.org/ChrootOnAndroid https://wiki.debian.org/Mobile
And no, nobody hates guys like you. Problem is that what you want to do is very similar to what malware might want to, and since malware is more common than guys like you, choices are made that way.