netfilter: exthdr: tcp option set support

Browse source

This allows setting 2 and 4 byte quantities in the tcp option space.
Main purpose is to allow native replacement for xt_TCPMSS to
work around pmtu blackholes.

Writes to kind and len are now allowed at the moment, it does not seem
useful to do this as it causes corruption of the tcp option space.

We can always lift this restriction later if a use-case appears.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

...

This commit is contained in:

Florian Westphal 2017-08-08 15:15:29 +02:00 • committed by Pablo Neira Ayuso

parent 5e7d695a48

commit 99d1712bc4

2 changed files with 165 additions and 3 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

4

include/uapi/linux/netfilter/nf_tables.h

View file

164

net/netfilter/nft_exthdr.c

View file