How to bump yourself stock kernel, modify ramdisk to add init.d + SELinux permissive - G3 Android Development

Hello,
I spent a lot of time searching and finding the material to understand and reproduce process about bump!.
After a few times shared the results of my manipulations on stock kernel, which I applied the method I'll describe here, I will try now to explain how you can make for yourself an identical result.
If you are still wondering what is Bump! I can only invite you to look for yourself, and even give you the link where I tried to answer this question on the section of the G2.
The purpose of this topic is to get you to bump kernel, from a PC, Linux, or Windows, or even from the phone.
I'll try to explain as why certain steps are essential to ensure a good result, steps that, at first, did not seem obvious.
When you will try it, and will want to test the result, make sure nice to have taken the necessary precautions before: Make a backup of your current kernel foremost flashing.
Now, you know what is BUMP! and why kernel must be bumped. Bump! basically involves injecting a signature in a file (boot).
This injection of the signature to be made in hexadecimal format, and immediately after the last used page of the kernel, we have to remove unnecessary bytes before doing so, and unpack/repack kernel is the easiest way to do so (http://forum.xda-developers.com/showpost.php?p=60086231&postcount=42). To do that, we need two binaries (unpackbootimg and mkbootimg).
About these two binaries, we can compile them ourselves from source, or taking already compiled bins.
@osm0sis made and share a super tool containing all that we need, these compiled bins, in his Android Image Kitchen - Unpack/Repack Kernel Ramdisk [Win/Android/Linux].
So i propose to use it here. The big advantage to this, is that @osm0sis compiled for windows, linux, and phone (arm). He created scripts that automate unpack and repack too.
The purpose of this topic is not to learn how to get the kernel file (boot), I assume that this prerequisite is acquired. However, I give you some hints for beginners, you can take a look at KDZ and TOT Extractor from @bullghost or the dd command to achieve.
1) Simply Bump a stock kernel in Linux (no change in ramdisk) to obtain a bumped working untouched stock kernel
Download the linux version of Android Image Kitchen - Unpack/Repack Kernel Ramdisk [Win/Android/Linux] ( AIK-Linux-v1.9.1-ALL.tar.gz), and untar it somewhere. Create, in the root directory of AIK, one file named "one_shot_bump.sh" (or the name that you like) containing this code I gave in osm0sis AIK thread (or, if you prefer, you can take the file named "linux_one_shot_bump_only.tar.gz" in attached files here), and chmod it 755.
Now you can use it by opening a terminal and drag and drop this file inside following by drag and drop kernel file too. Press enter, it's done You'll find a file named bumped.img, in AIK root directory, wich is your bumped kernel.
Note: bash for this script is very important for an expected result for printf cmd. It doesn't work as expected with sh.
2) Simply Bump a stock kernel in Windows (no change in ramdisk) to obtain a bumped working untouched stock kernel
I've not made a one click script to bump on this OS, but I'll explain very simply how to get there using the scripts offered natively in the osm0sis tools . This fair will be in three stages, for the reasons discussed in the preamble:
1) unpack the kernel
2) repack the kernel
3) inject hexa signature (bump!)
So to begin, download the windows version of Android Image Kitchen - Unpack/Repack Kernel Ramdisk [Win/Android/Linux] (Android.Image.Kitchen.v2.3-Win32.zip).
Unzip it where you want. Open a dos prompt and drag and drop unpackimg.bat on the prompt windows, tape one spaces in the command and drag and drop your kernel file in the prompt windows. Tape on enter: You made the first step, your kernel is unpacked.
Don't close window prompt, tape one touch to continue, as the prompt invite you to do.
Now, just drag and drop repackimg.bat in the prompt windows, and tape on enter. Done, you just finished the second step, you've repacked the kernel (image-new.img on the root folder of AIK).
Now, for doing the step 3, you need to inject the signature. I have not found other solutions at the moment than to use a hex editor to do this. I tried with a shareware (Hex Editor) and also with a freeware (HxD) with succes for these two softwares. With Hex Editor, after opening image-new.img, click on the first free byte at the end of the file and copy paste there "41A9E467744D1D1BA429F2ECEA655279" (without double quote). Save the file.
Or with HxD, after opening image-new.img, click at the end of the file, just after the last used byte, and in the menu"edition", choose "insert bytes". On the dialog box, type 10 on the first field (amount), let "hex" checked, and paste in the second field the value "41A9E467744D1D1BA429F2ECEA655279" (without double quote). Save the file.
Done, you just finished bumping your kernel in windows
I can give later screenshot if needed/asked.
Edit: i've found a workaround for using @osmosis tool to sign (bump) kernel just after repacking. Details can be found here: http://forum.xda-developers.com/showthread.php?p=63884919#post63884919
Edit2: After talking with @osmosis, the best solution for signing (bump) the kernel just after repacking should be to use cygwin printf.exe (I've attached this file to this post), that can be added in aik/bin folder (the real name of this folder is android_win_tools and it can be found in the root of AIK tool). So we just need to put printf.exe in android_win_tools folder, and replace this code in repackimg.bat
Code:
%bin%\mkbootimg --kernel "split_img/%kernel%" %ramdisk% %second% --cmdline "%cmdline%" --board "%board%" --base %base% --pagesize %pagesize% --kernel_offset %kerneloff% --ramdisk_offset %ramdiskoff% %second_offset% --tags_offset %tagsoff% %dtb% -o image-new.img %errout%
by
Code:
%bin%\mkbootimg --kernel "split_img/%kernel%" %ramdisk% %second% --cmdline "%cmdline%" --board "%board%" --base %base% --pagesize %pagesize% --kernel_offset %kerneloff% --ramdisk_offset %ramdiskoff% %second_offset% --tags_offset %tagsoff% %dtb% -o image-new.img %errout%
%bin%\printf \x41\xA9\xE4\x67\x74\x4D\x1D\x1B\xA4\x29\xF2\xEC\xEA\x65\x52\x79 >> image-new.img
As you can see, just one new line was inserted for injecting the signature.
3) Simply Bump a stock kernel in Phone (no change in ramdisk) to obtain a bumped working untouched stock kernel
I will not reinvent the wheel, you can use an existing tool for some time, made by @somboons, which uses the technique I mentioned here (unpack the kernel, repack it and injection of signing , all in the phone).
This script is an adaptation of Live bump by @Skin1980 that uses the arm versions of unpackbootimg and mkbootimg.
You will find the instructions and the tool here:
http://forum.xda-developers.com/lg-g2/development/tools-bump-kernel-offline-t3073261
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Credits and thank's a lot:
codefire team for bump!:
@thecubed , @Shelnutt2 , @IllegalArgument , @autoprime , @AnimatronicRocketReptile , @Dees_Troy
@Skin1980 for his live bump and these explanations
@osm0sis for his Android Image Kitchen - Unpack/Repack Kernel Ramdisk [Win/Android/Linux]
@zequav for explain me at the beginning what happen with bump and what can be done on linux

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How to add init.d support and SELinux permissive on the Ramdisk​
Here, i explain how to implement in Ramdisk init.d and SELinux permissive.
We start from untouched kernel not bumped (so not from the kernel we eventually have bumped with the previous post).
Use @osmosis tool android image kitchen version for your system to unpack it.
After that, navigate to the AIK root folder and:
in split_img/boot.bin-cmdline, replace
Code:
console=ttyHSL0,115200,n8 user_debug=31 ehci-hcd.park=3 msm_rtb.filter=0x37 androidboot.hardware=g3
by
Code:
console=ttyHSL0,115200,n8 user_debug=31 ehci-hcd.park=3 msm_rtb.filter=0x37 androidboot.hardware=g3 androidboot.selinux=permissive
in ramdisk/init.qcom.rc replace
Code:
on property:sys.boot_completed=1
start qcom-post-boot
by
Code:
service sysinit /sbin/sysinit.sh
oneshot
class late_start
user root
group root
disabled
on property:sys.boot_completed=1
start qcom-post-boot
start sysinit
and on /sbin folder, add a file named "sysinit.sh" that contains this code:
Code:
#!/system/bin/sh
mount -o rw,remount /system
if [ ! -e /system/etc/init.d ]; then
mkdir /system/etc/init.d
chown -R root.root /system/etc/init.d
chmod -R 755 /system/etc/init.d
fi;
mount -o ro,remount /system
run-parts /system/etc/init.d/
/system/xbin/daemonsu --auto-daemon &
Note: This previous code on sysinit.sh is only for those who have run-parts installed (with busybox by example). Otherwise, for those who don't want to use run-parts, you can put the next one that don't need it:
Code:
#!/system/bin/sh
mount -o rw,remount /system
if [ ! -e /system/etc/init.d ]; then
mkdir /system/etc/init.d
chown -R root.root /system/etc/init.d
chmod -R 755 /system/etc/init.d
fi;
mount -o ro,remount /system
setenforce 0
FILES=/system/etc/init.d/*
for f in $FILES
do
$f
done
/system/xbin/daemonsu --auto-daemon &
Now you are ready to repack the kernel. Use AIK repackimg script for that. After repacking the kernel, you still have to sign it (Bump!).
For this last formality depending on the OS which you find yourself:
1) On Linux
put a file that you name as you want with sh ext(bump.sh should be a great idea ) on the AIK root folder, and chmod it 755.
On this file put the code above:
Code:
#!/bin/bash
printf '\x41\xA9\xE4\x67\x74\x4D\x1D\x1B\xA4\x29\xF2\xEC\xEA\x65\x52\x79' >> image-new.img
Save it, and now just drag and drop this file on a window terminal and valid. That's all
2) On Windows
Refer to the OP, i explained there how I bump on windows
3) On Phone
Refer to the OP, i explained there how I bump on the phone

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Wow great, waiting for chapter 2

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reserved

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u25150 said:
Wow great, waiting for chapter 2
Click to expand...
Click to collapse
I feel that few people seem really passionate about what I say, if I refer to the answers
Also I'm going to focus on those who, like you, arise, and seem interested in this subject.
What specifically would you like to see some detail (what do you call "chapter two" ) ?
Duckscreen said:
reserved
Click to expand...
Click to collapse
Welcome, pleased to meet you

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@6ril1 great work my freind

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jac10000 said:
@6ril1 great work my freind
Click to expand...
Click to collapse
Hi my friend (not my freind, which is an advantage of German expression, ) , thank's, I assume that it is better to teach to fish than give fish, but perhaps this concept is it outdated ?

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Could you making how to kexec hardboot patch Guide please
(for support Multirom)

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Really nice work my friend !!!
In Linux, I just make my first bump boot thanks to you :good:

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jac10000 said:
Really nice work my friend !!!
In Linux, I just make my first bump boot thanks to you :good:
Click to expand...
Click to collapse
You are welcome
And great thank's for having notify me my mistake about code i wrote in post 2 (class late_sart instead of class late_start )
Code is edited and correct now

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Yeaah @6ril1 and my first bump boot with SELinux permissive

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jac10000 said:
Yeaah @6ril1 and my first bump boot with SELinux permissive
Click to expand...
Click to collapse
LOL, thank's to have testing all of that i described in this thread, and for having mentioning me in private some others mistakes (unexpected one space inserted during copy-paste on the post 2 and one code tag not closed) . I have edited again with all that you find and now it should be correct
THANK'S again my friend

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For windows user, new stuff added, i'll edit op with that too:
http://forum.xda-developers.com/showpost.php?p=63884919&postcount=716
Edit2: One more simple solution just added in OP

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I have new-img but how do you use hex editor exactly? i can not figure it out. can u help with screenshots please?

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I tried your tutorial (windows x64)(only bump no change in ramdisk) for 30c MM kernel but my phone wont boot(i don't have security error). Any ideas? Thank you!