This is needed because in ndisc.c, we have:

  static void ndisc_router_discovery(struct sk_buff *skb)
  {
  // ...
  	if (ndopts.nd_opts_mtu) {
  // ...
  			if (rt)
  				rt->u.dst.metrics[RTAX_MTU-1] = mtu;

  			rt6_mtu_change(skb->dev, mtu);
  // ...
  }

Since the mtu is set directly here, rt6_mtu_change_route thinks that
it is unchanged, and so it fails to update the MSS accordingly.  This
patch lets rt6_mtu_change_route still update MSS if old_mtu == new_mtu.
Signed-off-by: NJim Paris <jim@jtan.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add the net parameter to udp_get_port family of calls and
udp_lookup one and use it to filter sockets.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a net argument to inet6_lookup and propagate it further.
Actually, this is tcp-v6 implementation of what was done for
tcp-v4 sockets in a previous patch.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a net argument to inet_lookup and propagate it further
into lookup calls. Plus tune the __inet_check_established.

The dccp and inet_diag, which use that lookup functions
pass the init_net into them.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This tags the inet_bind_bucket struct with net pointer,
initializes it during creation and makes a filtering
during lookup.

A better hashfn, that takes the net into account is to
be done in the future, but currently all bind buckets
with similar port will be in one hash chain.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These two functions are the same except for what they call
to "check_established" and "hash" for a socket.

This saves half-a-kilo for ipv4 and ipv6.

 add/remove: 1/0 grow/shrink: 1/4 up/down: 582/-1128 (-546)
 function                                     old     new   delta
 __inet_hash_connect                            -     577    +577
 arp_ignore                                   108     113      +5
 static.hint                                    8       4      -4
 rt_worker_func                               376     372      -4
 inet6_hash_connect                           584      25    -559
 inet_hash_connect                            586      25    -561
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We have INET_MATCH, INET_TW_MATCH and INET6_MATCH to test sockets and
twbuckets for matching, but ipv6 twbuckets are tested manually.

Here's the INET6_TW_MATCH to help with it.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

  CHECK   net/netfilter/xt_iprange.c
net/netfilter/xt_iprange.c:104:19: warning: restricted degrades to integer
net/netfilter/xt_iprange.c:104:37: warning: restricted degrades to integer
net/netfilter/xt_iprange.c:104:19: warning: restricted degrades to integer
net/netfilter/xt_iprange.c:104:37: warning: restricted degrades to integer
net/netfilter/xt_iprange.c:104:19: warning: restricted degrades to integer
net/netfilter/xt_iprange.c:104:37: warning: restricted degrades to integer
net/netfilter/xt_iprange.c:104:19: warning: restricted degrades to integer
net/netfilter/xt_iprange.c:104:37: warning: restricted degrades to integer
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reported by Ingo Molnar:

 net/built-in.o: In function `ip_queue_init':
 ip_queue.c:(.init.text+0x322c): undefined reference to `net_ipv4_ctl_path'

Fix the build error and also handle CONFIG_PROC_FS=n properly.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Constify a few data tables use const qualifiers on variables where
possible in the nf_conntrack_icmp* sources.
Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Constify a few data tables use const qualifiers on variables where
possible in the nf_*_proto_tcp sources.
Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Annotate nf_conntrack_sane variables with const qualifier and remove
a few casts.
Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Constify data tables (predominantly in nf_conntrack_h323_types.c, but
also a few in nf_conntrack_h323_asn1.c) and use const qualifiers on
variables where possible in the h323 sources.
Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAlexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Propagate netns together with AF down to ->start/->next/->stop
iterators. Choose table based on netns and AF for showing.
Signed-off-by: NAlexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are many small but still wrong things with /proc/net/*_tables_*
so I decided to do overhaul simultaneously making it more suitable for
per-netns /proc/net/*_tables_* implementation.

Fix
a) xt_get_idx() duplicating now standard seq_list_start/seq_list_next
   iterators
b) tables/matches/targets list was chosen again and again on every ->next
c) multiple useless "af >= NPROTO" checks -- we simple don't supply invalid
   AFs there and registration function should BUG_ON instead.

   Regardless, the one in ->next() is the most useless -- ->next doesn't
   run at all if ->start fails.
d) Don't use mutex_lock_interruptible() -- it can fail and ->stop is
   executed even if ->start failed, so unlock without lock is possible.

As side effect, streamline code by splitting xt_tgt_ops into xt_target_ops,
xt_matches_ops, xt_tables_ops.

xt_tables_ops hooks will be changed by per-netns code. Code of
xt_matches_ops, xt_target_ops is identical except the list chosen for
iterating, but I think consolidating code for two files not worth it
given "<< 16" hacks needed for it.

[Patrick: removed unused enum in x_tables.c]
Signed-off-by: NAlexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduces the xt_hashlimit match revision 1. It adds support for
kernel-level inversion and grouping source and/or destination IP
addresses, allowing to limit on a per-subnet basis. While this would
technically obsolete xt_limit, xt_hashlimit is a more expensive due
to the hashbucketing.

Kernel-level inversion: Previously you had to do user-level inversion:

	iptables -N foo
	iptables -A foo -m hashlimit --hashlimit(-upto) 5/s -j RETURN
	iptables -A foo -j DROP
	iptables -A INPUT -j foo

now it is simpler:

	iptables -A INPUT -m hashlimit --hashlimit-over 5/s -j DROP
Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's unused static inline.
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The following feature was submitted some months ago. It forces the dump
of mark during the connection destruction event. The induced load is
quiet small and the patch is usefull to provide an easy way to filter
event on user side without having to keep an hash in userspace.
Signed-off-by: NEric Leblond <eric@inl.fr>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

-total: 81 errors, 3 warnings, 876 lines checked
+total: 44 errors, 3 warnings, 876 lines checked

There is still work to be done, but that's for another patch.
Signed-off-by: NJan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since we're using RCU, all users of nf_nat_lock take a write_lock.
Switch it to a spinlock.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rename all "conntrack" variables to "ct" for more consistency and
avoiding some overly long lines.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

early_drop() is only called *very* rarely, unfortunately gcc inlines it
into the hotpath because there is only a single caller. Explicitly mark
it noinline.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reorder struct nf_conntrack_l4proto so all members used during packet
processing are in the same cacheline.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Avoid calling jhash three times and hash the entire tuple in one go.

  __hash_conntrack | -485 # 760 -> 275, # inlines: 3 -> 1, size inlines: 717 -> 252
 1 function changed, 485 bytes removed
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

nf_ct_tuple_src_equal() and nf_ct_tuple_dst_equal() both compare the protocol
numbers. Unfortunately gcc doesn't optimize out the second comparison, so
remove it and prefix both functions with __ to indicate that they should not
be used directly.

Saves another 16 byte of text in __nf_conntrack_find() on x86_64:

  nf_conntrack_tuple_taken |  -20 # 320 -> 300, size inlines: 181 -> 161
  __nf_conntrack_find      |  -16 # 267 -> 251, size inlines: 127 -> 115
  __nf_conntrack_confirm   |  -40 # 875 -> 835, size inlines: 570 -> 537
 3 functions changed, 76 bytes removed
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ignoring specific entries in __nf_conntrack_find() is only needed by NAT
for nf_conntrack_tuple_taken(). Remove it from __nf_conntrack_find()
and make nf_conntrack_tuple_taken() search the hash itself.

Saves 54 bytes of text in the hotpath on x86_64:

  __nf_conntrack_find      |  -54 # 321 -> 267, # inlines: 3 -> 2, size inlines: 181 -> 127
  nf_conntrack_tuple_taken | +305 # 15 -> 320, lexblocks: 0 -> 3, # inlines: 0 -> 3, size inlines: 0 -> 181
  nf_conntrack_find_get    |   -2 # 90 -> 88
 3 functions changed, 305 bytes added, 56 bytes removed, diff: +249
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With the RCU conversion only write_lock usages of nf_conntrack_lock are
left (except one read_lock that should actually use write_lock in the
H.323 helper). Switch to a spinlock.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use RCU for expectation hash. This doesn't buy much for conntrack
runtime performance, but allows to reduce the use of nf_conntrack_lock
for /proc and nf_netlink_conntrack.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>