unreadable but bootable cdrom;)

drenal · 06-22-2004, 12:08 PM

Hi, today I worked with some bootable cdrom. It really works and it's some private version of program that copies installation files to hard drive.. I'm wondering how to read any files on this cdrom.. I think this log shows you enough:

Code:

$ cd /mnt
/mnt$ mount cdrom
/mnt$ df -m  |grep cdrom
/dev/sr0                   351       351         0 100% /mnt/cdrom
/mnt$ cd cdrom
/mnt/cdrom$ ls -al
razem 3
dr-xr-xr-x   1 root root 2048 1970-01-01 01:00 ./
drwxr-xr-x  16 root root  672 2004-06-16 00:28 ../
/mnt/cdrom$ du -ms
1       .

I have never met with this before, and I'm wondering how can I read any file on this cdrom and how can I create myself these unreadable(??) cd's

I googled but.. .. I'm not english and I don't know how to ask google for this.

I tested to read this cd on some different OS's and nothing is seen but capacity.

Mara · 06-22-2004, 04:00 PM

There might be a strange filesystem (or no filesystem at all), so you may not be able to mount it. If I'm rightt, to make such a cd, you'd need to write a program that reads the cd directly (working as an OS, because it's bootable), 'mounts' the hard disk and copies the files. In simplier case, there would be just a compressed file written directly to the disk (after certain needed structure).
But I've never seen such a cd, so I'm just saying how I'd do this.

drenal · 06-22-2004, 04:26 PM

Ok, thanks for your post.

I just add that after boot there is some menu where I can choose: format, make partitions and copy instalation files some very old, almost forgotten os w1ndz98 :P

Code:

# mount | grep cdrom
/dev/sr0 on /mnt/cdrom type iso9660 (ro,noexec,nosuid,nodev)
#dd if=/dev/cdrom of=backup.iso
# du -m backup.iso
351     backup.iso

I'm not able (yet;P) to write this kind of stuff now... I think it's nice piece of assember.. but the idea is really cool for me.

greets

Mara · 06-23-2004, 05:31 PM

So it may be that it just uses some extensions (read: Joliet) your kernel doesn't have. Do you have Joliet support in your kernel (in the kernel or as a module)?