I wrote:
> > Incidentally, do these attacks apply to traffic analysis of IPSEC
> > connections using something like FreeS/WAN?
>
> Yes. It's harder if there is other traffic using the same IPsec
> connection, but there might not be.
Oops, one thing I forgot to mention: it's also a bit harder because IPsec
always pads the packet out to the block size of the encryption algorithm,
even if no extra padding is added, and the information about *how much*
padding is present is hidden inside the encryption. So even without extra
padding, packet sizes are known only modulo 8 (all currently-common
ciphers use 8-byte blocks), which will make it rather harder to do things
like identifying the "su" command by packet size.
Henry Spencer
henry@xxxxxxxxxxxxx
Linux-crypto: cryptography in and on the Linux system
Archive: http://mail.nl.linux.org/linux-crypto/
