The symmetric ciphers
Philipp Klaus Krause
pkk at spth.de
Wed Oct 30 20:25:41 CET 2013
-----BEGIN PGP SIGNED MESSAGE-----
Am 10.09.2013 12:35, schrieb Philipp Klaus Krause:
> I wonder if it would be a good idea to have an option to combine
> symmetric ciphers, e.g. users could state a preference list like
> TWOFISH+AES256 3DES+BLOWFISH+AES AES 3DES
> The meaning of A+B would be to encrypt using A first, and then
> encrypt the result using B with a different key. Assuming it takes
> effort a to break cipher A and effort b to break cipher b, this
> should result in effort at least max(a, b) needed to break A+B. And
> with uncertainity about possible weaknesses in individual ciphers,
> this seems like a reasonable measure to me.
If we have plenty of randomness available, we could do this a
XOR the message M with a random one-time pad P to obtain N. Encrypt P
with A, and N with B.
The drawback is that this doubles the lenth of the message.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.15 (GNU/Linux)
Comment: Using GnuPG with Icedove - http://www.enigmail.net/
-----END PGP SIGNATURE-----
More information about the Gnupg-users