Database Develop

Root Technical Details

Hi, I've been searching for technical details of how root is actually obtained on the Android system. Specifically, I'm interesting in the Nexus One, but I'm curious about any methods that are available.
After reading the adb documentation among others, I've come to the belief that at least on the N1 it's as simple as remounting system as root and changing the permissions of su followed by installing busybox. After that the superuser application is installed, and it updates su with it's own version.
(This is only for updating the application on an already rooted system)
Superuser appears to grant root privileges to itself then overwrites su with it's own variation that uses its database for permissions, and calls the app with:
Code:
sprintf(sysCmd, "am start -a android.intent.action.MAIN -n com.koushikdutta.superuser/com.koushikdutta.superuser.SuperuserRequestActivity --ei uid %d --ei pid %d > /dev/null", g_puid, ppid);
I'm curious how cyanogen handles it without having the user install busybox, etc. before flashing his mod. I would think the Android system would only allow signed updates, but I have a feeling that the custom recovery image bypasses that.
If someone could just link me to a forum link/blog/etc. (if they exist) or give me some advice on things to search for, that would be great.
I'm just now getting into Android kernel development, and would love to know everything I can about it. I've been way to busy with a research project at school, but it's pretty much over at this point. I plan on becoming much more involved here especially with some programming some ideas I have for improvements to both the kernel and Google's applications.

meinhimmel said:
I'm curious how cyanogen handles it without having the user install busybox, etc. before flashing his mod. I would think the Android system would only allow signed updates, but I have a feeling that the custom recovery image bypasses that.
If someone could just link me to a forum link/blog/etc. (if they exist) or give me some advice on things to search for, that would be great.
.
Click to expand...
Click to collapse
bingo. upon unlocking the bootloader, you are able to flash a custom recovery which does not require google keys and you are able to install custom roms. the roms usually have busybox and the other applications built in. custom recovery also has all the binaries require for flashing roms.
a good site would be platform.android.com (something like that) for developing roms/editing kernel. you can also check the "android development" on the xda main forum homepage, there are a couple of stickies there worth reading

[Q] Could this actually work for our milestones (Q)

Could this possibly work for our milestones? (Just a question, beginner here)
http://www.phonedog.com/2011/01/20/why-is-motorola-continuing-to-lock-bootloaders/ :
Motorola made it extra difficult – for some – to do what they wanted in terms of software and loading ROMs. Some developers got smart about this though, and an application named Droid X Recovery Bootstrap (by Koush) popped up in Android Market. This application hijacked parts of the boot process and fooled the system into thinking everything was okay. In other words, it was a workaround for Motorola's sneaky and unwelcome software. Point being, no matter how hard a company works to prevent users from loading ROMs on their Android devices or jailbreaking their iPhones, developers find a way around it. Every time. Most people are fond of Motorola's nice build quality, but not everyone is a fan of MOTOBLUR; the same could be said of HTC and Sense UI. So why not give users a choice or at least assist them in making their phone what they want it to be?

Yes, but there is an easier way to boot into recovery.

It doesn't help us at all;
http://www.koushikdutta.com/2010/08/droid-x-recovery.html

So can we now install custom ROMs?
Yes, but you can't replace the kernel or boot image. But really, once you have access to /system, anything is possible. It will just take a little hackery.
Click to expand...
Click to collapse
we don't need tht to gain access to /system. we already got access to /system thts why u can see alot of custom mods downs here. which i think is much better compared to any others custom rom as alot of our dev's are pro's and really spent alot of time to make the mods almost perfect.

We are using similar way to boot custom ROMs on Milestone for some time already.
1. sh-hijack to take over the control during the early init phase (on init)
https://github.com/nadlabak/android_system_core/commit/6c27adb5b0e33f214c48ee2411a717f6343c81b8
(hacked sh will run /system/bin/sh_hijack.sh instead of /init_prep_keypad.sh)
2. 2nd-init run from sh-hijack script, to restart the init process with custom init.rc scripts in use
https://github.com/nadlabak/android_device_motorola_umts_sholes/blob/froyo/prebuilt/bin/sh_hijack.sh
(copy init scripts from /etc/rootfs to root and run 2nd-init)
https://github.com/nadlabak/android_device_motorola_umts_sholes/blob/froyo/prebuilt/bin/2nd-init.c
(restart init)

SHBEAK "error installing binary file:java.io.IOexception"

Can some care to help me, I having trouble running the application so called SHbreak "error installing binary file:java.io.IOexception".
Well I try to use this to temporary root the Regza IS04 this the only way I know to temporary root.
z4root, gingerbreak superoneclick and many other rooting application to pc or android is no good because according to Japaneses blog The regza is04 kernel have a system lock
I'm talking about the android version 2.2.2 basedband ver 5014.1907.43
because the android version 2.2.1 can easily be root by z4root because there's no system lock
This is the guide for rooting Toshiba Regza IS04 from Japanese blog
One. root folder
We do the following to solve the problem of big inconvenience especially on the acquisition process and the root, is used.
In the normal-release kernel / system lock
· "Rogue applications ~" solutions for the errors
· Place / symlink to a path such as system / bin / su
By enabling the su using ISTweak, after this process, you can use the authority root.
application require
SHBREAK
ISTWEAK
Root explorer
ISTweak is for temporary root but before to able to use it you need to copy au from SHBREAK
But error keep pop up Error installing binary file:java.io.IOexception
Please Someone help me to what to do..

Wrong forum
Sent from my DHD

This seems to be happening a lot in this forum. Either people don't read and do not realize where they are or having the 'one' title for this phone is very confusing.

HTC one M7 is clear enough
Sent from my Nexus 4 using xda premium

You would thinks so.

[Q] Root without supersu app

Hello,
I want to use a Moto G 2014 in some kind of kiosk mode. That means modified rom with only one application that runs in front of everything. This application, all future helper scripts and system binaries must have root access. So I would like to have a su binary without the supersu app, that may pop-up and ask for permission.
I know I can change the settings of supersu not to pop-up and ask. But I recently had some problems with this settings and the dialog showed up again.
I would feel much better if there was a way to run the su binary without the needed interaction with the supersu app. I have googled for a few hours and read threads here in the forums. But I haven't found a good way to do this. Most answers refer to a normal phone and why the user should keep supersu.
- Do you have any glue how to do this?
- Is the su binary of supersu somewhere OpenSource, so I can modify it to get rid of the communication with the app?
- Are there any alternatives to supersu that work with lollipop?
- Is there already a working patched linker for the Moto G 2014 to bypass PIE
Alternatives:
https://github.com/koush/Superuser/issues/268 seems not to work with lollipop because of PIE
Thank you for your help!

Can't even install XPosed (Flashfire Issue?)

So I got around to "rooting" my "LG G4" (H525) via that one click tool called Kingroot.
So far so fine.
Pretty much all applications that require root will will allow it...
Except for one:
FlashFire....
It keeps telling me that root access was not possible,
that I shall't install SuperSU.
[However SuperSU will error out right on the start telling me to `update the binary']
=> What binary ? Why update it (just got the newest SuperSU from the Playstore)?
Trying to flash said binary using any Flashify merly showed me the lovely "your device is bricked" bugdroid...
Any idead from someone with similar FlashFire / SuperSU problems ?
Thanks in advance:
-Rye-

Do you have a custom recovery/twrp?
Sent from my HTC One M9 using Tapatalk

Nope, all stock.
(Part of the reason why this confuses me so much... I changed nothing... except for Root)

KingRoot is intentionally designed to serve two purposes. The first is to give you root access through their app. The second, which they don't warn you about, is to prevent you from managing that root access any other way than through their app.
They have written their app specifically to force you to use their root manager and to prevent you from uninstalling it and installing any other SU app. They went so far as to specifically block installation of SuperSU because they're upset that it replaces their app (which is blatantly absurd and hypocritical). If that's acceptable to you, then certainly do it their way.
However, because they place such restriction on root access (which seems to be a self-contradictory philosophy) then it directly interferes with the installation of more powerful root apps like flashing utilities and Xposed itself.
At this point there are two options. Either you can find a utility that breaks their stranglehold on your device and follow the specific instructions to remove their app and install something that's not restrictive, or you can restore your device to pre-root condition and root it again yourself using the open, non-restrictive methods made available to the community. Each method may be about as complicated as the other.