Crypted Filesystem

[jpmatrix]

hi
did someone try any way of using a Crytped FileSystem on a Zaurus ?
doing a google search i found some clues:  loop-aes, CFS, TCFS, BestCrypt and Cryptfs... so does someone has any experience about that on the Z ?

[Da_Blitz]

have done it but not on a zaurus, its not that hard once you have losetup (which i belive the zaurus dose not have)

anyway you create a file or partition and fill it up with random data (ie dd if=/dev/random/ of=`your file or partition here` bs=1024K count =128) that should fill the directory up with 128 MB of random data (you can skip this setp as it can take a long time and you have to move the mouse and type to help generate random data) i belive doing this for 200GB was calculated at takig 3 days if some one was using the computer 24/7

next you call losetup and bind the file to a loop devices (ie /dev/loopx) with losetup -e aes `path to file or partition` /dev/loop0 (type losetup without any arguments for some simple help as i am doing this from memorey) just a word of warning -e allows you to specify a name, while -E allows yo to specify a number that represents a kernel module for encryption

it will then ask you for a password, chose somthing nice and long

next fromat the /dev/loopx device with mkfs.ext2 -j /dev/loopx

then mount /dev/loopx somewhere and you are done, keep in mind you have to type the password every time you mount but when you remount it is posible to get the mount command to auto allocate a loop device and handel the losetup stuff for you (see the mount man pages near the end)

if you need any more help just post here but the guides work farily well a good one is at www.tldp.org

[jpmatrix]

have done it but not on a zaurus, its not that hard once you have losetup (which i belive the zaurus dose not have)

i apt-cache searched losetup and i found it is part of loop-aes. did i guess right ?
well, apparently i can install it under debian-X/Qt

but doing a search on killefiz.de i found what could be enough for me at now : BURP

http://www.killefiz.de/zaurus/showdetail.php?app=758
http://www.geodyssey.com/cryptography/cryptography.html

i've to try.
thanks anyway!

[Da_Blitz]

yep that should be all you need, i belive in the 2.6 kernels you had to have the aes module compiled into or as a module for it to work but i am unsure for 2.4, if it works post it up i would like to try it again

i ten to prefer the losetup to burp as i can encrypt a partion transperently without having to wory about it to much, one other option could be the use of pgp to encrypt the files, this is normally the prefered soulotion for those people who dont use losetup on thier machine (handy if you dont have root accsess)

[kcurrie]

encfs  (http://encfs.sourceforge.net/) should work fine, I use it on my laptop with great success.  You just need the fuse module compiled and you're good to go.   encfs isn't that heavy on the CPU and doesn't required to preallocate space like you have to do with any of the loopback filesystem options.