lenovo bios update cd extraction

notes.txt

# warewolf@xasf:~/hack$ md5sum g2uj30us.iso 
d6c1685c192f4fc62c53ff7bc7cb54a0  g2uj30us.iso
# warewolf@xasf:~/hack$ isoinfo -d -i g2uj30us.iso 
CD-ROM is in ISO 9660 format
System id: 
Volume id: g2uj30us
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: 16566
El Torito VD version 1 found, boot catalog is in sector 20
Joliet with UCS level 3 found
NO Rock Ridge present
Eltorito validation header:
    Hid 1
    Arch 0 (x86)
    ID 'NERO BURNING ROM'
    Key 55 AA
    Eltorito defaultboot header:
        Bootid 88 (bootable)
        Boot media 4 (Hard Disk Emulation) # so this is a hard drive emulation boot image   
        Load segment 7C0
        Sys type 6
        Nsect 1
        Bootoff 1B 27
        
     
# warewolf@xasf:~/hack$ geteltorito.pl g2uj30us.iso > boot.img # from https://raw.githubusercontent.com/ksergey/thinkpad/master/geteltorito.pl
Booting catalog starts at sector: 20 
Manufacturer of CD: NERO BURNING ROM
Image architecture: x86
Boot media type is: harddisk
El Torito image starts at sector 27 and has 65536 sector(s) of 512 Bytes
Image has been written to stdout ....

# warewolf@xasf:~/hack$ md5sum boot.img
588071b1c4dc3db8e10232492283e6ab  boot.img
# warewolf@xasf:~/hack$ file boot.img 
boot.img: DOS/MBR boot sector; partition 1 : ID=0x4, active, start-CHS (0x0,1,1), end-CHS (0x1f,63,32), startsector 32, 65504 sectors

# this ended up being a fat16 filesystem, which starts at 16k in

# warewolf@xasf:~/hack$ sudo mount -o loop,offset=$[16*1024] boot.img mount
# warewolf@xasf:~/hack$ sudo find . -type f -iname \*.fl2
./FLASH/G2ETB4WW/$01D3000.FL2
# warewolf@xasf:~/hack$ sudo md5sum FLASH/G2ETB4WW/\$01D3000.FL2
68ef8766aba0aa919df9da45c1f67e86  FLASH/G2ETB4WW/$01D3000.FL2
-rwx------ 1 root root 12718080 Feb  6  2015 'FLASH/G2ETB4WW/$01D3000.FL2'