bootable CD-ROM image to memstick image?

[Ian Smith]

On Sun, 29 Jun 2014 08:03:45 -0600, Warren Block wrote:
 > On Sun, 29 Jun 2014, Warren Block wrote:
 > > On Sun, 29 Jun 2014, Ian Smith wrote:
 > > 
 > > > I have a bootable BIOS/EC update CD image for a Lenovo X200, with no CD.
 > > > 
 > > > It contains the same good ol' DOS 6.0 BIOS update program as ever, after
 > > > a loader from not so good ol' Nero Burning ROM, after 64KB of zeroes.
 > > > 
 > > > root at x200:~smithi/biosupdate # file 6duj48us.iso
 > > > 6duj48us.iso: # ISO 9660 CD-ROM filesystem data '6DUJ48US
 > > > ' (bootable)
 > > > root at x200:~smithi/biosupdate # mdconfig -f 6duj48us.iso
 > > > md0
 > > > root at x200:~smithi/biosupdate # mount_cd9660 /dev/md0 /mnt
 > > > root at x200:~smithi/biosupdate # ls -a /mnt
 > > > .       ..
 > > > root at x200:~smithi/biosupdate #
 > > > 
 > > > Is there a generic way to convert this into a bootable USB image?
 > > 
 > > Possibly the update program and data is in the El Torito floppy image. I've
 > > converted floppy images to boot CDs, but not the other way.  This might
 > > help: http://arstechnica.com/civis/viewtopic.php?f=16&t=308491

Indeed, based on that and finding isoinfo already installed, I just ran 
it and was about ready to come back with more questions, when .. ding:

 > And based on that:
 > 
 >   % isoinfo -d -i 6duj48us.iso
 >   Setting input-charset to 'ISO8859-1' from locale.
 >   CD-ROM is in ISO 9660 format
 >   System id:
 >   Volume id: 6DUJ48US
 >   Volume set id:
 >   Publisher id:
 >   Data preparer id:
 >   Application id: NERO BURNING ROM
 >   Copyright File id:
 >   Abstract File id:
 >   Bibliographic File id:
 >   Volume set size is: 1
 >   Volume set sequence number is: 1
 >   Logical block size is: 2048
 >   Volume size is: 19126
 >   El Torito VD version 1 found, boot catalog is in sector 20
 > 
 >   Joliet with UCS level 3 found.
 >   No SUSP/Rock Ridge present
 >   Eltorito validation header:
 >       Hid 1
 >       Arch 0 (x86)
 >       ID 'NERO BURNING ROM'
 >       Cksum 8A FC OK
 >       Key 55 AA
 >       Eltorito defaultboot header:
 >           Bootid 88 (bootable)
 >           Boot media 4 (Hard Disk Emulation)
 >           Load segment 7C0
 >           Sys type 6
 >           Nsect 1
 >           Bootoff 1B 27

Well that matches my copy.  Did you just have one lying around? :)

 >   % dd if=6duj48us.iso of=zoot.img bs=2048 skip=27 count=75744
 >   19126+0 records in
 >   19126+0 records out
 >   39170048 bytes transferred in 0.063829 secs (613672181 bytes/sec)
 > 
 > That file is a 37M MBR hard drive image.  Copying it straight to a memory
 > stick ought to work.

Using skip=27 does indeed start at the loader, with the DOS 6.0 MBR at 
0x4000 after 16KiB zeroes.

I was confused by count=75744, some 148MiB at 2K sectors, but count is 
ignored unless less than filesize anyway, so any larger value - or no 
value at all - works, great, but then our record counts don't agree:

root at x200:~ # dd if=/home/smithi/biosupdate/6duj48us.iso of=6duj48us.img 
 bs=2048 skip=27
19099+0 records in
19099+0 records out
39114752 bytes transferred in 0.477592 secs (81899933 bytes/sec)

Your 19126 records would be the whole file, 30170048 bytes here, so it 
looks like 'skip=27' didn't skip on yours, or I'm missing something?

Pressing on, plugging in a spare stick:

root at x200:~ # dd if=6duj48us.img of=/dev/da0 bs=2048 conv=sync
19099+0 records in
19099+0 records out
39114752 bytes transferred in 24.952938 secs (1567541 bytes/sec)

root at x200:~ # ll /dev/da*
crw-rw----  1 root  operator  0x93 Jun 30 02:51 /dev/da0
crw-rw----  1 root  operator  0x94 Jun 30 02:51 /dev/da0s1

Wow, that stick had a /dev/da0a there before.  This looks promising ..

root at x200:~ # mount_msdosfs /dev/da0s1 /dist
root at x200:~ # ls -lrt /dist
total 184
-rwxr-xr-x  1 root  wheel   9349 Dec 31  1993 WINA20.386*
-r-xr-xr-x  1 root  wheel  37174 Dec 31  1993 IBMDOS.COM*
-r-xr-xr-x  1 root  wheel  40758 Dec 31  1993 IBMBIO.COM*
-rwxr-xr-x  1 root  wheel  54654 Dec 31  1993 COMMAND.COM*
-rwxr-xr-x  1 root  wheel  14160 Nov 18  1994 HIMEM.SYS*
-rwxr-xr-x  1 root  wheel  12663 Apr 23  1999 RAMDRIVE.SYS*
drwxr-xr-x  1 root  wheel   2048 Apr  4  2008 System Volume Information/
-rwxr-xr-x  1 root  wheel    123 Apr 15  2009 CONFIG.SYS*
-rwxr-xr-x  1 root  wheel     58 Feb  5  2013 AUTOEXEC.BAT*
drwxr-xr-x  1 root  wheel   2048 May 10  2013 $RECYCLE.BIN/
drwxr-xr-x  1 root  wheel   2048 May 10  2013 EFI/
drwxr-xr-x  1 root  wheel   2048 May 10  2013 Flash/
drwxr-xr-x  1 root  wheel   2048 Jun 13  2013 Recycled/

Cool!  I'll have to backup some stuff before trying it, manyana.

Thanks heaps,

Ian