Create a custom firmware image

From NAS-Central Buffalo - The Linkstation Wiki

Revision as of 05:41, 31 October 2006

Most of this information was taken from the excellent hacking how-to of geishuettners page.

WARNING! CAUTION: Experts only

WARNING! There is a possibility that you could brick your NAS with these instructions. Please make sure that you read the entire page carefully.

This is a description how someone can create a custom firmware image.

This is also the way any special distribution (Projects/OpenLink,Projects/FreeLink,Projects/GenLink) gets developed. (and of course - this was the way how telnet was added to the images)

Note: For the LS Pro (LS-GL), image.dat is called hddrootfs.img and the tarball of the root file system is called hddrootfs.buffalo.updated . If you are making an image for the LS-GL, you will need to alter the commands below accordingly.

There is only one requirment ->You have to know the password of image.dat

1) unzip the image.dat that resides in the zip-file of the base image with the right password

 unzip image.dat

provide the right password for the firmware.

the result of this is a tmpimage.tgz...this is the tared root-filesystem of the firmware image.

2) create a folder where you want to untar the image and untar it

 mkdir <foldername>
 cd <foldername>
 tar -vxz --numeric-owner -p -f ../tmpimage.tgz

now you can see the root-filesystem which normaly resides on /dev/hda1 (or / )

3) modify the image as you like Advice: use relative paths if you create symlinks. absolute paths won`t work.

4) create the tmpimage.tgz again

(you should be in the folder where you extracted the image)

 tar -vczf ../tmpimage-new.tgz .
 cd ..
 mv tmpimage.tgz tmpimage-old.tgz
 mv tmpimage-new.tgz tmpimage.tgz

Note: The LS-GL must be tared with the -C flag

 tar -vczf ../hddrootfs.buffalo.updated-new -C /absolute/pathe/to/extracted_image dir1 dir2

dir1, dir2, and so forth are the directories located under the extracted image folder (i.e. bin, dev, etc, home, lib, ...)

 cd ..
 mv hddrootfs.buffalo.updated hddrootfs.buffalo.updated-old
 mv hddrootfs.buffalo.updated-net hddrootfs.buffalo.updated

5) create the image.dat again

CAUTION: if you use the wrong password, the firmware updater / the linkstation will fail to unzip the image.dat.....this means you will have a wiped /dev/hda1 with no files on it.

Opening the case will be the only possible solutions.

 zip -e image.dat tmpimage.tgz

you should have a custom image.dat afterwards :)