When ip6_route_me_harder is invoked, it resets outgoing interface of:
  - link-local scoped packets sent by neighbor discovery
  - multicast packets sent by MLD host
  - multicast packets send by MLD proxy daemon that sets outgoing
    interface through IPV6_PKTINFO ipi6_ifindex

Link-local and multicast packets must keep their original oif after
ip6_route_me_harder is called.

Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

similar to previous change, this also allows to remove it
from nf_ipv6_ops and avoid the indirection.

It also removes the bogus dependency of nf_conntrack_ipv6 on ipv6 module:
ipv6 checksum functions are built into kernel even if CONFIG_IPV6=m,
but ipv6/netfilter.o isn't.

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

For some reason, Florian forgot to apply to ip6_route_me_harder
the fix that went in commit 29e09229d9f2 ("netfilter: use
skb_to_full_sk in ip_route_me_harder")

Fixes: ca6fb0651883 ("tcp: attach SYNACK messages to request sockets instead of listener") 
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

This abstraction has no clients anymore, remove it.

This is what remains from previous authors, so correct copyright
statement after recent modifications and code removal.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

This is only needed by nf_queue, place this code where it belongs.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

We cannot make a direct call to nf_ip6_reroute() because that would result
in autoloading the 'ipv6' module because of symbol dependencies.
Therefore, define reroute indirection in nf_ipv6_ops where this really
belongs to.

For IPv4, we can indeed make a direct function call, which is faster,
given IPv4 is built-in in the networking code by default. Still,
CONFIG_INET=n and CONFIG_NETFILTER=y is possible, so define empty inline
stub for IPv4 in such case.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

We cannot make a direct call to nf_ip6_route() because that would result
in autoloading the 'ipv6' module because of symbol dependencies.
Therefore, define route indirection in nf_ipv6_ops where this really
belongs to.

For IPv4, we can indeed make a direct function call, which is faster,
given IPv4 is built-in in the networking code by default. Still,
CONFIG_INET=n and CONFIG_NETFILTER=y is possible, so define empty inline
stub for IPv4 in such case.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

This is only used by nf_queue.c and this function comes with no symbol
dependencies with IPv6, it just refers to structure layouts. Therefore,
we can replace it by a direct function call from where it belongs.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

We cannot make a direct call to nf_ip6_checksum_partial() because that
would result in autoloading the 'ipv6' module because of symbol
dependencies.  Therefore, define checksum_partial indirection in
nf_ipv6_ops where this really belongs to.

For IPv4, we can indeed make a direct function call, which is faster,
given IPv4 is built-in in the networking code by default. Still,
CONFIG_INET=n and CONFIG_NETFILTER=y is possible, so define empty inline
stub for IPv4 in such case.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

We cannot make a direct call to nf_ip6_checksum() because that would
result in autoloading the 'ipv6' module because of symbol dependencies.
Therefore, define checksum indirection in nf_ipv6_ops where this really
belongs to.

For IPv4, we can indeed make a direct function call, which is faster,
given IPv4 is built-in in the networking code by default. Still,
CONFIG_INET=n and CONFIG_NETFILTER=y is possible, so define empty inline
stub for IPv4 in such case.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>