Pass netns to xfrm_lookup()/__xfrm_lookup(). For that pass netns
to flow_cache_lookup() and resolver callback.

Take it from socket or netdevice. Stub DECnet to init_net.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

'tcp: Port redirection support for TCP' (a3116ac5) added a new member
to inet_request_sock() which inet_csk_clone() makes use of but failed
to add proper initialization to the IPv6 syncookie code and missed a
couple of places where the new member should be used instead of
inet_sk(sk)->sport.
Signed-off-by: NKOVACS Krisztian <hidden@sch.bme.hu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

cookie_v6_check() did not call reqsk_free() if xfrm_lookup() fails,
leaking the request sock.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ecn_ok is not initialized when a connection is established by cookies.
The cookie syn-ack never sets ECN, so ecn_ok must be set to 0.

Spotted using ns-3/network simulation cradle simulator and valgrind.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Wei Yongjun noticed that we may call reqsk_free on request sock objects where
the opt fields may not be initialized, fix it by introducing inet_reqsk_alloc
where we initialize ->opt to NULL and set ->pktopts to NULL in
inet6_reqsk_alloc.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow the use of SACK and window scaling when syncookies are used
and the client supports tcp timestamps. Options are encoded into
the timestamp sent in the syn-ack and restored from the timestamp
echo when the ack is received.

Based on earlier work by Glenn Griffin.
This patch avoids increasing the size of structs by encoding TCP
options into the least significant bits of the timestamp and
by not using any 'timestamp offset'.

The downside is that the timestamp sent in the packet after the synack
will increase by several seconds.

changes since v1:
 don't duplicate timestamp echo decoding function, put it into ipv4/syncookie.c
 and have ipv6/syncookies.c use it.
 Feedback from Glenn Griffin: fix line indented with spaces, kill redundant if ()
Reviewed-by: NHagen Paul Pfeifer <hagen@jauu.net>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

the first u32 copied from syncookie_secret is overwritten by the
minute-counter four lines below.  After adjusting the destination
address, the size of syncookie_secret can be reduced accordingly.

AFAICS, the only other user of syncookie_secret[] is the ipv6
syncookie support.  Because ipv6 syncookies only grab 44 bytes from
syncookie_secret[], this shouldn't affect them in any way.

With fixes from Glenn Griffin.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Acked-by: NGlenn Griffin <ggriffin.kernel@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Updated to incorporate Eric's suggestion of using a per cpu buffer
rather than allocating on the stack.  Just a two line change, but will
resend in it's entirety.
Signed-off-by: NGlenn Griffin <ggriffin.kernel@gmail.com>
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>