On Sun, Jul 09, 2006 at 06:06:35PM +0200, Joachim Schipper wrote: > > I'm looking for a stream cipher in the kernel that is fairly secure. Does > > it > > exist? Alternatively I'm looking for a block cipher that does CFB > > (Cipher Feedback Mode). There is a prototype stub for DES CFB in > > /sys/crypto/des.h but I don't see a des.c file in the 3.9 sources, is it > > taken > > out of a userland library? > > The kernel includes quite a bit of crypto, though I'm not sure how to > get at all of it - but svnd(4) uses Blowfish, and ipsec(4) uses almost > all of the well-known block algorithms. > > What are you trying to do? > > Joachim
I'm trying to encrypt a stream, per byte (8 bit) instead of per block (usually 8 bytes) in the kernel. CFB and OFB ciphers are ok if they are a block cipher as they pretty well can encrypt per byte according to applied cryptography from schneier. Anyhow I'll take a look at the svnd code, perhaps the author of the device uses CFB or OFB cipher modes as blowfish is a 8 byte block cipher. Oh yeah, I considered a one time pad as an alternative for the purpose, but I cannot do it, as the receiving is not guaranteed to be in sequence which one time pads need to be to effectively change a byte back to cleartext. I also cannot get around that with error correction / checksumming. kind regards, -peter -- Here my ticker tape .signature #### My name is Peter Philipp #### lynx -dump "http://en.wikipedia.org/w/index.php?title=Pufferfish&oldid=20768394"; | sed -n 131,136p #### So long and thanks for all the fish!!!
