Hi,
I'm interested in purchasing a Nexus 4 I have no cellphone plan, nor do I want one; instead I intend to use the phone as a tablet or PDA.
I would like to hear some feedback on how feasible it is to low-level remove the cell and gps antennas' capabilities. Is there a driver or kernel module of some sort that could be removed to 'neuter' the phone? Can the hardware run the antennas without the ROM or kernel's consent?
I've already read about the code to reach a developer menu and 'disable radio' as well as 'airplane mode'. Neither of these fit the bill, I want the phone to be incapable of transmitting cell/gps information.
I would love to join the android community, but I will not feel comfortable until I know that the device isn't going to hand over my location to anyone with a crafty enough story at the police department, which I believe makes this question one of security rather than battery life or functionality.
My apologies if this is posted in the wrong section, I decided that the android forum would be most appropriate because I'm curious about how android manages the cellular antenna rather than something specific to the Nexus.
Thanks!,
BigBubbaX said:
Hi,
I'm interested in purchasing a Nexus 4 I have no cellphone plan, nor do I want one; instead I intend to use the phone as a tablet or PDA.
I would like to hear some feedback on how feasible it is to low-level remove the cell and gps antennas' capabilities. Is there a driver or kernel module of some sort that could be removed to 'neuter' the phone? Can the hardware run the antennas without the ROM or kernel's consent?
I've already read about the code to reach a developer menu and 'disable radio' as well as 'airplane mode'. Neither of these fit the bill, I want the phone to be incapable of transmitting cell/gps information.
I would love to join the android community, but I will not feel comfortable until I know that the device isn't going to hand over my location to anyone with a crafty enough story at the police department, which I believe makes this question one of security rather than battery life or functionality.
My apologies if this is posted in the wrong section, I decided that the android forum would be most appropriate because I'm curious about how android manages the cellular antenna rather than something specific to the Nexus.
Thanks!,
Click to expand...
Click to collapse
I am also interested in this...
I bet if one can compile a kernel for his own device, it is possible to disable the GPS and related drives in the module/kernel config.
and this would completely kill the feature... so no risk of any spyware app triggering it etc...
however it may not make sense to use maps on the device... unless you want to bluetooth pair it to another GPS device.
Nexus is great... but I want to be able to do this for a different phone which may not be as popular on here.. than what ?
G
ghatothkach said:
I am also interested in this...
I bet if one can compile a kernel for his own device, it is possible to disable the GPS and related drives in the module/kernel config.
and this would completely kill the feature... so no risk of any spyware app triggering it etc...
however it may not make sense to use maps on the device... unless you want to bluetooth pair it to another GPS device.
Nexus is great... but I want to be able to do this for a different phone which may not be as popular on here.. than what ?
G
Click to expand...
Click to collapse
Hi ghatothkach,
I'm still working on this. First I need to assemble a x64 computer capable of compiling a ROM from source, then I'll see if I can find a way to nullify the radio drivers. If it's possible for the Nexus, I'm pretty sure a similar workflow will be available for your phone.
There are also some other aspects of Android that I'd like to look at for security concerns, such as the way that the phone currently broadcasts a list of wireless networks which it is associated with.
I apologize for digging up an old thread, but has there been any development on this subject? Or physically removing or disabling the GPS receiver on a phone?
6 years later..
Question remains.
Is that possible to root the device and delete the gps driver/kernel completely?
If yes which of the file as to be removed
0
Related
do any of the custom kernels currently developed for the Thunderbolt, support wireless "N"? Thanks in advance.
The phone supports the wireless n protocol by default out of the box. If it's not working, it's you, not the phone.
Kenerls help support the wifi. If the kernel does support "N", the the phone will not. Thanks for ur support tough guy.
Sent from my ADR6400L using XDA App
I wasn't being a jerk, you're just overreacting and assume my short answer was being rude and some sort of attack on your intelligence. I didn't see a point of giving a tl;dr answer you probably aren't interested in.
But here's the tl;dr version:
Instead of jumping on me, you could look up how drivers work. Your phone supports wireless n because the kernel in the phone has the proper wireless driver for it compiled in. On linux, there aren't a lot of choices for wireless drivers and since there's most likely only one choice for the wireless driver with this hardware and revision type (and it comes linked and ready to compile with the kernel source given from HTC that all the kernels listed in the developer forum are using). The phone's hardware supports wireless n and any drivers made for it by default will have it as well. So by that, if wifi works at all on your phone, so will wireless n--unless someone was specifically screwing with you and ripped out the wireless n protocol support in the driver source code, but happened to leave g and b, which most likely be a pain and be hard to do without breaking the entire driver itself.
If you want to be technical, all the kernels are based off the one that came with your phone in some way and have the same drivers compiled in; hence, they support the wireless n protocol. No developer is going to remove the wifi drivers to a kernel on purpose and if it were missing, someone would quickly notice. With that in mind, if the phone doesn't seem to pick up a wireless n signal, it's not the phone, it's you (or indirectly your router/hotspot location).
Honestly though, if a short answer doesn't work for you and assuming you are going to take a long answer at face value because it has some big technical words thrown into it that make it look credible and don't want to dig up an answer by googling or flashing one of the kernels to see for yourself, what is the point of writing it all out?
If that was all too tl;dr, the short answer is once again, yes, they all have "Wifi N kernel support."
Also, my answer is free, no need to donate to me
Not all customs kernels support wifi N. Ask a couple devs.
Sent from my ADR6400L using XDA App
Please do not rehost the testing software over at infectedrom - I would like to maintain some control if possible to ensure things do not get out of hand going forward. I am not trying to write viruses, just show how the issue works so we can all protect ourselfs. While I cannot stop anyone from turning the code malicious I highly frown upon modifying this to write values in any way. Trust me from experience, you dont want to play anyway you will probably just bork your own wimax.
Note: Please be aware that rooting your phone to install this patch will void your warranty with HTC. You should all already be aware of this when you unlocked your bootloader. As with anything posted in these dev boards this patch may also affect the functionality of your device, so proceed at your own caution!!!
What are we patching?
This post is a call to arms for help from devs on patching the issue shown in PoC#2. You can read the vulnerability report and find test software to see if you are effected over on infectedrom. HTC has been notified on this particular issue on October 20th so they will be working on an official patch.
Download
http://www.androidfilehost.com/main/.TrevE/PoC2/TrevE_WiMAX_Patch.zip is an unofficial patch I started that anyone can use / modify / whatever attached to this post. Its crude but its an immediate quick fix that cuts the negative implications down by manually stop & start wimax services / show 4g settings.
Using Patch:
In a nutshell these 3 binaries do not need to always run, and them being flawed we want them off all the time. When you want to use 4g, start the above app and turn on the binaries then 4g radio like usual.
If you do not want to edit ramdisk you should be able to use the app just to stop the binaries each boot.
To disable these binaries completely and only start when there needed edit init.shooter.rc to appear as below (or wherever binaries are started in ramdisk) and manually start them when you are going on 4g with attached app.
Code:
service wimaxDaemon /system/bin/wimaxDaemon
user root
group root
disabled
oneshot
# setWMXPropd daemon
service setWMXPropd /system/bin/
setWiMAXPropDaemond
user root
group root
disabled
oneshot
# getWMXPropd daemon
service getWMXPropd /system/bin/getWiMAXPropDaemond
user root
group root
disabled
oneshot
Big thanks to the help getting in touch with HTC from egzthunder1!
Other Possible patch solutions
The other issue I would like to bring to attention is the code was 99% the same from PoC#1 - connecting to 127.0.0.1. Is there anything we can do to make some kind of ipchain firewall blocking apps from access to certain resources? I would think this would be important for all rooted users especially having some type of easy firewall, and everything Ive seen seems primitive. Mobile malware is coming and we should be ahead of the tides.
Non Root solutions?
Non root users may be able to kill the PIDs or stop the services, I have not had the time to try.
TrevE said:
As always I think its a good general warning to stay away from shady apps, things arent always as sandboxed as you would think. While HTC is already working on an official patch for this and other issues where theres a will theres a way with malware. I think firewalls and protective measures need to start stepping up before things get worse, its a linux pc in our pockets with a radio - not just a phone anymore.
Click to expand...
Click to collapse
You always know how to keep us one step ahead, Thanks for this info
This is def way over my head...but I thought I should ask b/c im sure others will probably ask the same. Should I worry about this if I am not in a Wimax market? No Wimax within a 100+ miles from me at least (San Diego). I'm guessing not, but what do I know??
Thanks for looking out for us n00bs!
MFD00M said:
This is def way over my head...but I thought I should ask b/c im sure others will probably ask the same. Should I worry about this if I am not in a Wimax market? No Wimax within a 100+ miles from me at least (San Diego). I'm guessing not, but what do I know??
Thanks for looking out for us n00bs!
Click to expand...
Click to collapse
the issue effects all 3ds with wimax and more, I actually had mine in airplane mode with all radios off for video and was able to crash phone and read / write values.
videos rotating guys, sorry shot it alittle funny and running around right now....
Very interesting. Going to sit down and read real quick!
Gonna use it either way, but lets see whats we got going.
Thanx buddy!
hTc
I didn't really understand that, but it looks important. I'm not really sure but I think that the video meant that the wimax can be accessed when its not on. Something like that?
Read the article on this.... Sprint deserves a wag of the finger from Colbert. Its just dirty. Back doors like crazy. And why the **** would HTC not pro actively remove all the crap in the first security patch. They KNOW everything before we FIND it.
Sent from my PG86100 using Tapatalk
TrevE, would that LBE tool be enough to revoke privilege for network access?
not an expert, but we could probably port over the iptables and add some default configuration for our phone.
Heck, maybe I just build one. Ha.. MOM.
Thanks TrevE for being on this!
TrevE, thank you for putting this out there. And thank God you aren't a maligned dev, or we'd all be in trouble. HTC should be paying you for doing QC on their code. Oh, wait... I forgot, all this was on purpose.
Warm & cozy.
Always treve you are one step ahead of the dictatorship known as HTC and Sprint I am grateful your on our side man thank you
Sent from my PG86100 using xda premium
Well isn't this lovely, they set that up for debugging and forget to disable it or something?
Just read about this on Phandroid. Kinda crazy. Thanks Treve for all you do.
Sent from my SPH-D710 using xda premium
xHausx said:
Well isn't this lovely, they set that up for debugging and forget to disable it or something?
Click to expand...
Click to collapse
those binaries are actually whats called if you logcat connecting to wimax. While I cant say for sure my guess is it wasnt left open for debugging, more hey nobody will look here. The wimax monitoring port is very curious as well - if you look at the poc app it can query DUN state, release keys and rom versions among other things.
These ports look like they are never used until you connect to 4g, so the best solution I came up with is just shutting them off all the time and turning them on with an app before you connect 4g. This atleast limits vulnerability time from any random app reprogramming your wimax values to only be possible when your on 4g.
As always I think its a good general warning to stay away from shady apps, things arent always as sandboxed as you would think. While HTC is already working on an official patch for this and other issues where theres a will theres a way with malware. I think firewalls and protective measures need to start stepping up before things get worse, its a linux pc in our pockets with a radio - not just a phone anymore.
huytrang90 said:
TrevE, would that LBE tool be enough to revoke privilege for network access?
not an expert, but we could probably port over the iptables and add some default configuration for our phone.
Heck, maybe I just build one. Ha.. MOM.
Click to expand...
Click to collapse
Not sure, I kinda see this as a problem in android - local and internet arent really separated. I cant say for sure if revoking will work, download the proof of concept app and try This is one of the reasons i feel strongly about demonstrating issues like this, everyone can learn from it how it works and how to squash this stuff and protect ourselves. The last thing we need is winnuke/sasser/whatever on android.
Forgive for the noob??? But I'm just trying to gain an understanding of how to use this. Do I just edit the int file or use your app before I turn 4g on?? Also since Im in an area that has little to no 4g is there a quick way to completely disable the 4g antenna untill I want to use it??
Locked & Loaded
""shooter on Deck""
HTC loves you TrevE!
Good work again!
TrevE, I just gotta say, because it's not said enough, thank you. You are afaik the ONLY low-level dev still working for the end user in public, and I for one find it both heartening and praise-worthy. With all the drama we see around here, and get involved in, you still keep on pushing forward. I'm thoroughly grateful that you are doing this and not some douchebag hacker who wants to nuke our phones from the cloud
#idrankthekoolaid
One thing that bothers me about my Android phone is the opaque, closed-source baseband firmware ("radio" as it's often called here). Since the baseband is interposed between the OS and most hardware functions, its firmware presents a major unknown in the total security of the device.
It's unlikely that the source code for any of this baseband firmware is going to be released, and the open source OsmocomBB baseband is a long way off from supporting Android or the dominant Qualcomm chips. But I would settle for decompiling an existing baseband firmware image, so that I can start to understand some things about it's behavior, and perhaps compile modified versions.
Does anyone know where to begin with this? Many thanks.
I wish somebody participated in this with you. I need it also /
funkydaemon said:
One thing that bothers me about my Android phone is the opaque, closed-source baseband firmware ("radio" as it's often called here). Since the baseband is interposed between the OS and most hardware functions, its firmware presents a major unknown in the total security of the device.
It's unlikely that the source code for any of this baseband firmware is going to be released, and the open source OsmocomBB baseband is a long way off from supporting Android or the dominant Qualcomm chips. But I would settle for decompiling an existing baseband firmware image, so that I can start to understand some things about it's behavior, and perhaps compile modified versions.
Does anyone know where to begin with this? Many thanks.
Click to expand...
Click to collapse
Good idea. Although most probably it'll all be native C code compiled into binary form, not amenable to decompiling.
So you'd probably need a very good debugger and a system call tracing facility in strace.
I guess hell might also break loose because SIM encryption(?), voice encoders(?), network locking(?) and god knows how many of those proprietary tidbits may be sitting in there.
SIM encryption broken leading to duplication of SIMs and leading to smartcard encryption and open source tools to reprogram your credit cards with more money.
That's not hell. That's hell in a hand basket with us enjoying the ride
Keep us posted. It's guys like you who think outside the radio that gave us the TV
For Qualcomm based devices you need to decompile Hexagon code.
For other Intel XMM6260 etc based devices suffice IDA (ARM).
In both cases the raw binary blobs may be encrypted, but extractable from running machine.
I'm working on it, in a fashion, and am writing up a document compiling everything that has been done on cellphone radio hacking. I've not found much on baseband firmware; there's a lot of info out there but it's been tough to find amongst all the other hacking that has similar keywords. Currently most quality info around this subject involve an extra (and depending on desired features; expensive) bit of hardware and two open source software packages with their decencies. As the hardware is currently outside my budget ($300 for the best bang for buck) I'll be working on getting the software to recognize the hardware built in my Android devices. Provided that all goes well I should be able to read and write on the frequencies that the in-built hardware supports and hopefully, as I always get an identical device when getting one, read and write with my backup android device. Be warned if you decide to follow me down this path; there are laws restricting what non-licensed persons/companys can do on certain RF frequencies and this depends on where you live, I'm no expert only a person capable of reading lots of dry informative documents, provided I do achieve direct contact between devices this hack could (and likely will) fry one of my antennas so be warned you'll likely do the same :banghead: so do this on an old device that you don't care about before ever trying on something you use daily. With the warning out of the way lets get down to the quick version.
~~~~~~~~~~~~
Currently all the developing I've found educational has involved the before mentioned "expensive hardware" known as software defined radio, shortened to SDR, go a head and pop open a new tab and Google search either. You'll eventually find that cellphone manufacturers have likely already put these into many devices. You'll also hopefully find the two kickstarters, HackRF ~$300 and bladeRF ~$400, these are likely what I'll be saving up for; HackRF for sure as the next release will likely be able to send and receive at the same time instead of switching quickly between modes. If you dig deep enough you'll find a blog post from a hacker that plugged an Android into a much more expensive SDR and was able to place calls and send/receive text; the blog poster stated something to the effect that this was not a useful hack but I believe that it's a great proof of concept and totally worth another look. However, this hacker has also almost been sewed for some of the demonstrations with this kind of technology involving the capture and description of calls and texts so tread carefully.
The software I mentioned before boil down to GNU Radio and Open BTS; there's dependencies for each but all seem to be installable on Linux running on top of Android. Furthermore I see that someone (I'll edit your name in in a sec Edit: idcrisis ) previous mentioned wanting c or c++ support, GNU Radio uses these languages perhaps I can ask for some help when I get a little further in porting this to run without Linux in the middle so much? I think if we use the GPS to set the time then the signal shouldn't drift to much.
I'm using an app called Debian Kit to give me a flavor of Linux called Squeeze for testing the software. If you choose to try what I'm doing then make use of the readme that the developer wrote or the guide I wrote for general Linux on Android installation and interaction fund in my sig to get started. If you want access to the document I'm compiling then you'll want to PM me at this moment as the chances of hardware frying is high and I'll share a link to Google docs; I'll be releasing a full guide when I've figured out how to avoid damage.
Eventually I hope to port many of the functions in GNU Radio into an app that makes use of internal hardware. Currently I've found a few that make use of hardware plugged into Android through USB "on the go" or "host mode" just search "RTL SDR" in the app store and you'll see'em, but, currently nothing making use of internal hardware. If any are interested in joining forces and helping figure out how to do all this I'd be glad to offer any support I can.
Other things related to cellular antenna hacking other than the above mentioned software and hardware that I'm compiling into the same document. Well this is where we get into the parts I'm hitting the wall on. It looks like I'll have to get into Kernel modification as this is one of the things used to communicate between software and hardware. There's also the flashable files known as radios and I'll be digging further in how these files are modified.
Basically this is a very tough question to answer and has taken many months of reading, searching, and more reading to get this close bit if we all work together I know that we'll be able to modify how the antennas in our devices work.
Edit 01142014- Found a guide on reverse engineering embedded device firmware, the guide is on a router but as the chips in our phones are embedded perhaps the steps are similar
http://www.devttys0.com/2011/05/reverse-engineering-firmware-linksys-wag120n/
Sent from either my SPH-D700 or myTouch3gs or M470BSA
Guide for running Linux on Android that I'm writing:
http://forum.xda-developers.com/showthread.php?t=2240397
^^ NO! The embedded chips in the Linksys routers are MIPS based and not ARM like all our Androids. Very different, although technique is the same.
But thanks, for taking time to check up on all this.
Any updates ?
Hey Guys,
I'm looking into this, I've successfully extracted files from the OnePlus One's baseband, its running RtOS called REX, QC calls it AMSS.
Have a look at the thread here: http://forum.xda-developers.com/oneplus-one/general/discussion-hlos-reverse-engineering-t3292829
Waiting for the OsmocomBB update it projects
QCOM modem leaked sources.
Type in google/bing: "AU_LINUX_ANDROID_JB_MR1_RB1.04.02.02.050.116_msm8974_JB_MR1_RB1_CL3904528_release_AU"
Since I asked a lot of question on this forum I would like to share the answers with everybody and maybe help them.
NOTE: Please don't post any replys as I want to keep the post clean and room for updates, send me a PM if you have and idea or any fails that I made in this post, if this post helped you don't post hit just the thanks button. Cheers.
Current list of questions with answers(will be updated):
Why would I want to root my phone?
Is rooting worth the trouble?
Is rooting illegal?
Will I have any customer support?
Is it dangerous?
Isn't rooting a complex and difficult process?
Will I still receive operating system updates from my carrier?
Application updates?
What if I want to un-root my phone?
Do I run the risk of bricking my phone?
Could my phone overheat and explode?
Why would I want to root my phone?
Everything in a Linux system is a file, or is treated as a file. Since Android runs on top of Linux, it acts the same way. Most of the files you will need to access or change are available to you without having elevated permissions. "Most" being the key term here. When you want to do things that affect or change the core software of your device -- like updating the version of Android on your phone, or adding a nice piece of software from another device -- you'll have to do it as root. Dream and Magic users have been running Eclair on their phones for a good while now, and it’s because they have rooted their device. Rooting also gives you access to some handy software that you couldn’t use otherwise. Things like a complete system backup or ad blocking software require you to root your device. Don’t root your phone just for the sake of rooting your phone, but if you come across something you feel you could use or would like to have, then consider it. You'll find that the open source community is usually pretty helpful and encouraging new people to do new things is common. And when you get to the point where you can lend a hand to the new folks, pay it forward.
Is rooting worth the trouble?
The answer is a resounding yes. The phone is faster than it has ever been, the battery lasts longer, and have all kinds of new features, including free wireless tethering and notification-bar widgets. Rooting your phone is generally a fairly quick process, though the complexity depends on your specific situation. Once you're rooted your handset, you can begin installing apps (many directly from Android Market) that will take advantage of your handset's new capabilities. Installing custom ROMs (replacement operating systems) built by hackers is a longer, more involved process , and generally involves your wiping all the data from your phone, but even that is worthwhile.
Is rooting illegal?
Nope. You bought the phone, it's your equipment, you own it, and you can do what you want with it. No one is going to come and get you, and your service provider will not cancel your contract. In fact, the U.S. federal government recognized the legality of rooting a phone in July 2010.
What you will do, however, is void the warranty on your device. If you don't want to live without a warranty, rooting isn't for you. Personally, I finally decided to take the plunge when I realized that the potential benefits outweighed the potential consequences. My phone was becoming slow and buggy, with lots of force-closes, and I was just about eligible for an upgrade anyway.
Will I have any customer support?
Rooting can be daunting because there is no toll-free number you can call for help, and no governing body to which you can turn for definitive answers. But the collective process of rooting phones and creating custom ROMs has engendered cool and supportive communities. The user-generated forums out there contain a staggering amount of information; the CyanogenMod forum has offered answers to almost all of my questions, as has the XDA Developers forum, but you can find many more. No matter your question, the forums most likely already have threads that can answer it. If you really can't find anything, you can always start a new thread to ask your question. If you think you've really mucked things up and you need immediate help, many IRC chat channels specialize in support for rooters. (Download an IRC client on your computer and head to irc.freenode.net, where the channels #android and #android-root are particularly helpful.)
Is it dangerous?
It can be, It might, and Yes. By not allowing access to the superuser account, the manufacturer and your carrier have basically protected you from doing things that change the system and make it unusable. All it takes is one wrong keystroke to turn your shiny new Android phone into a plastic and metal brick with no connection. Most times this is recoverable, but not always. You have to decide how capable you feel you are, and how well written the instructions you’ve found seem to be. Nobody will blame you if you decide against the risk, especially your cell carrier. All major carriers and manufacturers plainly state that altering or using unapproved software voids your warranty, and rooting falls into that category. While that seems a bit harsh, they need to be able to support the products they sell. For that to happen, they need to know exactly what’s running and what it’s doing.
Apps that run as root need a little further consideration. You need to have a level of trust in the person who wrote the app first and foremost. Does the developer have other software available? Do the user comments (for Market apps) have anything that raises a red flag? Do the requested permissions seem a little odd? These are all questions you need to think about before you allow something to run as root. For a further level of security, think about installing an application that warns you anytime something tries to run as root. SuperUser Whitelist is a great little app that does exactly that. If you decide to go on and root, ask users with the same device as you for a link to a version of SuperUser Whitelist that works with your firmware. Once installed, anytime something wants to run as root, the app intercepts and asks if you would like to allow it. You’re given the choice to accept, decline, or grant the app in question full privileges each time it runs.
One last thing to touch on here. Many custom ROMs include some sort of SSH server. This can be a wonderful tool, or it can get you in hot water. This is what caused the whole “Rick-Roll” episode with the latest iPhone jailbreak. The server sits and waits for an outside connection, and if that connection provides the right password full control of the device is turned over. In the case of the iPhone, users never bothered to change the default SSH password for root. A clever (or devious) group of users simply scanned for servers listening on the correct port, then attempted to sign in as root with the default password. Lesson learned, but this is easy to prevent. Ask other users of the ROM or firmware you’re thinking of flashing if there is a server listening, and if so how to disable it or change the default password.
Isn't rooting a complex and difficult process?
Yes and no. It really depends on what model of phone you have. On many phones (such as the Nexus One, Motorola Defy, or EVO 4G) the process is incredibly easy: You can download an app such as Simple Root, Universal 1-Click, or Z4root that will safely root your phone with a single click. Those apps are no longer available from the Android Market, but you can find them online with a simple search and install them onto an SD Card.
It is important to note that different approaches will work for different phones. For example, Z4root will work on many Android phones, but it won't work on most HTC models. Some rooting apps will work on an early build of Android 2.2 (Froyo), but will not work on later builds (though more and more apps are being released for that now). Rooting is phone/OS specific, so make sure to check that the root tool you're considering is compatible with your phone. For other models, rooting may take much more work. You might be required to connect the phone to your computer and enter some lines of code in a terminal utility.
Fortunately, more and more root apps do not require you to hook up your computer and get in that deep. Do some research as to what is required for your setup, read some step-by-step guides, and be honest with yourself about how comfortable you would be trying to follow the directions. If it feels like you'd be in over your head, it's probably best to avoid rooting.
Note that generally rooting is even tougher to do if you use a Mac, as most of the software for doing this sort of thing is written for Windows or Linux.
Will I still receive operating system updates from my carrier?
Maybe. More than likely if you’ve just rooted your phone so you could have access to the full file system and haven’t drastically changed things, the phone will still pass your carrier's checks and upgrade. If you’ve delved deeper and really customized your device, count on not being able to upgrade. Carrier updates were designed to work with the original software, so they need to be sure that’s what the phone is running. Again, this is for your own good. T-Mobile or Verizon can’t offer technical support for things they haven’t trained their technicians on, and if you flash a carrier approved update over custom software it’s probably not going to work.
The good news is that failing the checks the carrier does during an update won’t cause any damage to your phone. The update will just quit and you’ll be back where you started. Then you can decide if you would like to un-root and upgrade or take another path. The worst case scenario is that the phone passes the carriers checks, updates, and then things get broken. That’s pretty unlikely, but possible. If that would happen, you won’t be alone. Everyone in your situation will scramble to their favorite Android user forum and hopefully a work around can be found.
Note - a carrier update may also break the ability to root the device and a new method will need to be found. Any discussion of upgrading and root needs this mentioned as well. Most folks who root and decide to install a custom ROM wait for the ROM developer to provide an update that includes any bug fixes or new capabilities of the carrier update.
Application updates?
Yes. While it’s not being used, the program that allows permissions to be upgraded just sits and does nothing. Normal applications won’t even be aware it’s there, and applications that use it expect it to be there. Application updates, whether they are from the Market or other third parties will still install as normal.
What if I want to un-root my phone?
It depends on the model of your phone. Some are ridiculously easy to revert, some not so much. This is the most important question you can ask before you dive in and root your phone. Usually the website you found the method to root your phone will also have a discussion about un-rooting and going back to stock firmware. Take the time to find and read this information so you’re aware of just how difficult it’s going to be to go back. Pay close attention and create backups when recommended while you’re rooting your phone, as these may be needed to go back. I’ve not heard of any device that can’t be restored to factory firmware provided the original was backed up properly as recommended during the rooting process. The most important thing to always remember is to ask for help. If you do find yourself stuck without a backup or a working phone and need to roll back, ask for advice. Our forums are full of fine folks from all walks of life, and the majority are more than happy to help. There’s a good chance you’re not the first person in that situation and a solution has already been worked up!
Do I run the risk of bricking my phone?
This is one of the Internet's favorite bogeymen. "Bricking" is the idea that if you try to tinker with root access, you'll mess something up so it becomes completely unusable, and you'll essentially turn your phone into a paperweight. While that's certainly not outside the realm of possibility, the good news is that Android phones are generally very hard to brick. Yes, even the Droid X, which was purported to be the "unrootable" phone, has been safely rooted for quite some time (Z4root reportedly works with the Droid X).
If you do get caught in a boot loop, you may have to connect your phone to your computer and rewrite some code, but if you are patient and willing to do some more reading, you will almost always be able to find a way to at least restore your phone to its original state (read more on where that help comes from in the next section).
A common mistake that actually will lead to a bricked phone is running out of battery power in the middle of trying to install a custom ROM. The operating system only half installs, and that really is tough to fix. So always make sure that your battery is full before you install a new OS or ROM.
Also, just because a phone is rootable does not mean you can install any custom ROM you want. Differerent ROMs will work for different phones. Even the extremely popular CyanogenMod works for many phones, but certainly not all, so do plenty of research to make sure your phone is supported before trying to install a custom ROM.
Could my phone overheat and explode?
One of the major incentives to root your phone is the ability to overclock your processor to gain more speed (or underclock it to extend battery life). My phone has gotten considerably faster because of overclocking. When you overclock your processor, though, it will get hotter. If you try to push your phone too far and you don't set any fail-safes (a maximum allowable temperature in the overclocking utility), then you could burn out your processor. However, it is very easy to set safety thresholds to ensure that you don't do that.
SetCPU, the most popular app for overclocking or underclocking, allows you to set up various profiles.
Reading the rooting forums will give you plenty of advice on how far you can push your specific device and maintain stability. It pays to do some experimentation: Different phones behave differently, even if they're the same model.
Sources: androidcentral.com, pcworld.com
Useful threads:
[TUTORIAL] Unlocking, rooting, custom roms installing, going back to stock
[INDEX] HTC Desire X (protou) - Everything Desire X is here!
Reserved.
Hi,
I'm working on a small project and am currently looking for a Tablet that I can use. As far as I understood, the "Sony Xperia Tablet Z2" (SGP 521) could be a good candidate for my project. I am asking this forum to potentially assist me with your knowledge and experience if the following is possible with the device:
(Some questions or comments seem to be obvious but I still write them down so that I can be sure we are talking on the same level. Please do not simply refer me to the search functionality of the forum, I did my homework and searched each of the topics before -- I just need a first-person-confirmation of someone if the below is really working.)
- I need to modify and compile the Linux (Android) Kernel of the device. Thus, the Source-Code of the Kernel for this device needs to freely available.
- The modified Kernel needs to be able to be uploaded and booting from the device, thus the Bootloader needs to be unlocked.
- The device needs to have running NFC and LTE communication, plus touch and usual tablet capabilities. For this, the necessary binary-drivers need to be able to be integrated to the custom kernel. I expect the drivers are not common (GPL-like) drivers but proprietary and at maximum available as binary-package to be integrated afterwards.
Is this all possible or can I expect major problems somewhere? The used LTE network most likely will be some LTE network in Germany. To my best knowledge, it is possible to unlook the bootloader and compile a custom kernel. Critical point is: Is NFC+LTE working and available as binary package to be integrated in the custom-kernel?
Thank you in advance for your time!
Best regards
Dennis
Perhaps you could first tell us (approximately) what you plan to do on the tablet.
That could probably save you quite an amount of superfluous time and work if your plan doesn't make any sense.
hasenbein1966 said:
Perhaps you could first tell us (approximately) what you plan to do on the tablet.
That could probably save you quite an amount of superfluous time and work if your plan doesn't make any sense.
Click to expand...
Click to collapse
Sure. Since I did not write much about my past experience, you simply can be sure that similar projects finished successful already. I've done similar things with Nexus and previous Google/Android developer devices, without much problems.
Back to your question:
The idea is to develop an application to be put on a nfc-capable external device to provide some external computed value. Afterwards, the tablet needs to communicate to the application on the external device, using a protocol I design that in the end uses common NFC communication and protocols. Finally, the Tablet sends results of the external-nfc-cabable device through LTE to the Internet, thus the LTE interface is only used to provide Internet functionality.
Does this answer cover your question properly?
Best Regards
Dennis
Really nobody uses a Sony Xperia Tablet Z2?
/push
I am really wondering nobody is using the Sony Xperia Tablet Z2 (SGP521) with LTE and once installed a custom Kernel (maybe Cyanogen Mod?) and afterwards used anything with NFC + Internet. Simply can't believe that.
If there is anyone, please confirm that NFC + Internet (using LTE) is working with a custom compiled kernel.
Best regards
Dennis