tree b544746f70bda6413105887fe1e6d28399840e23
parent 15c67286685cddce207b646306e8819ec8268ede
author Herbert Xu <herbert@gondor.apana.org.au> 1196817053 +1100
committer Herbert Xu <herbert@gondor.apana.org.au> 1199999805 +1100

[CRYPTO] eseqiv: Add Encrypted Sequence Number IV Generator

This generator generates an IV based on a sequence number by xoring it
with a salt and then encrypting it with the same key as used to encrypt
the plain text.  This algorithm requires that the block size be equal
to the IV size.  It is mainly useful for CBC.

It has one noteworthy property that for IPsec the IV happens to lie
just before the plain text so the IV generation simply increases the
number of encrypted blocks by one.  Therefore the cost of this generator
is entirely dependent on the speed of the underlying cipher.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>