encryption

amdunlock · Posted: Sun Apr 25, 2004 8:42 pm Post subject: encryption

hi, i have free place on my hdd, where i want to create an encrypted partition. can i have a safety of 99% ?
which program should i take ? i have know AES. is that good ?
the best thing would be a key cd, which contains the key.
also a cd, which i have to mounted, if i will mount my loop partition.

thanks a lot olli
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smart · Guru Joined: 19 Nov 2002 Posts: 455

Hi there,
i'd suggest you to use the cryptoloop in the kernel. (2.6 series in my case). The cipher to use is a bit religious. I preferred IDEA a lot since it's non US and as far as ciphers go, i feel that's an advantage. Again a religious thing you see.

Now i use twofish.
One decision helper, though, not for the cipher but the partition.
I went with a partition based cryptdevice, too, 'cause i thought that removes a filesystem layer, possibly/probably gaining some performance and dropping some complexity.
Well, meanwhile i think i should have worried less about these two since it's more convenient to work with a file. E.g. for backup/copying and most importantly, you can easily access that directly from a networked machine. Didn't try it, but i thought it would be nice to have it as a file that you can access via NFS. Since the crypto is done locally, well you have your networked, secure storage via internet if you want.

barlad · l33t Joined: 22 Feb 2003 Posts: 673

I use loopAES. That's pretty straight forward to set up and the documentation is just plain great. I suggest you take a look at it.

amdunlock · Posted: Mon Apr 26, 2004 1:09 pm Post subject:

hmm is a loop AES 256/128bit safety enough ?

and whats the difference beetween IDEA and twofish ?
_________________
-2500+ @ 3200+ ---- 512MB-Ram watercooled Htf X Triple @ 3 x 5V - Abit AN7 s*cking microguru - Geforce 6800 - Audigy 2 -=Gentoo Stage 2004.2 @ ext3=-

kpack · Tux's lil' helper Joined: 29 Mar 2004 Posts: 137

See this link for a information about cipers:

http://www.jisc.ac.uk/index.cfm?name=jcas_papers_ciphers

amdunlock · Posted: Mon Apr 26, 2004 2:24 pm Post subject:

k thanks a very lot for the link. i took twofish, and i think, thats a good choise or ?
i compiled it in my kernel. can i make then a partition how i would do this with AES ?

thanks a lot
_________________
-2500+ @ 3200+ ---- 512MB-Ram watercooled Htf X Triple @ 3 x 5V - Abit AN7 s*cking microguru - Geforce 6800 - Audigy 2 -=Gentoo Stage 2004.2 @ ext3=-

smart · Guru Joined: 19 Nov 2002 Posts: 455

Have a look at the losetup manpage. If i remember right there are some nice samples at the end...

barlad · l33t Joined: 22 Feb 2003 Posts: 673

You should really read the doc of loopAES, there are a lot of examples at the end and it will help you to understand how all of this works, which is quite interesting.
Making an encrypted partition with loopAES is quite easy. A few commands to type (you can just copy/paste the doc, heh.) and you are done

.

Anyway, both twofish and AES are great choices.