We may hit this in xt_LOG:

net/built-in.o:xt_LOG.c:function dump_ipv6_packet:
	error: undefined reference to 'ip6t_ext_hdr'

happens with these config options:

CONFIG_NETFILTER_XT_TARGET_LOG=y
CONFIG_IP6_NF_IPTABLES=m

ip6t_ext_hdr is fairly small and it is called in the packet path.
Make it static inline.

Reported-by: Simon Kirby <sim@netnation.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

ipt_LOG and ip6_LOG have a lot of common code, merge them
to reduce duplicate code.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

These types are guaranteed to be defined by <linux/types.h> for
both userland and kernel, unlike u_intN_t.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Resolve these warnings on `make headers_check`:

usr/include/linux/netfilter/xt_CT.h:7: found __[us]{8,16,32,64} type
without #include <linux/types.h>
...

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

Unification of struct *_error_target was forgotten in
v2.6.16-1689-g1e30a01.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

Many of the used macros are just there for userspace compatibility.
Substitute the in-kernel code to directly use the terminal macro
and stuff the defines into #ifndef __KERNEL__ sections.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>