tree cc8b186b50e182d14acc88e2b8de2208f5943545
parent 175a407ce432088d827b822b8a47afd8360a8dbe
author Eric Dumazet <edumazet@google.com> 1565996487 +0100
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1566723102 +0200

inet: switch IP ID generator to siphash

commit df453700e8d81b1bdafdf684365ee2b9431fb702 upstream.

According to Amit Klein and Benny Pinkas, IP ID generation is too weak
and might be used by attackers.

Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix())
having 64bit key and Jenkins hash is risky.

It is time to switch to siphash and its 128bit keys.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Reported-by: Benny Pinkas <benny@pinkas.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>