on Thu, Jul 05, 2001 at 01:31:02PM -0700, David Freeman scribbled:
I seamed to have missed the beginning of this thread so I assume its something about secure filesystems.
Being a sad nerd who has read Cryptonomicon, the code book and applied cryptography too many times I have been looking at secure file systems. I was looking at a 128mb disk which is stored on the harddisk as shutdown but which is mounted into ram on boot up, so I get a steganographic Ram disk? Does anyone know if this is possible?
Yes, but what happens if you have a power cut or some other crash? ups i guess.
You can get the stegfs patches and utils from http://www.mcdonald.org.uk/StegFS/ although last time I tried it, it wasn't very stable - could have just been me and it was 1999/2000. Then simply compile a kernel with ramdisk support, grab srm/smem by thc. http://packetstorm.securify.com/groups/thc/ is the most working url I can find at the moment..
So at boot up you just: 0) dd if=/stegramfs of=/dev/ram0 bs=1m count=128 (might be ramdisk size issues here..also might want to store it more encrypted) 1) mount (params) /dev/ram0 /somefs 2) srm /stegramfs 3) use stegfs stuff later to access it
and shut down: 0) umount /dev/ram0 1) dd if=/dev/ram0 of=/stegramfs bs=1m count=128 2) smem