vpnc on today's kernel says Cannot open "/proc/sys/net/ipv4/route/flush":
d--------- 0 root root 0 2008-08-26 11:32 /proc/sys/net/ipv4/route
d--------- 0 root root 0 2008-08-26 19:16 /proc/sys/net/ipv4/neigh
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net.ipv4.neigh should be a part of skeleton to avoid ordering problems
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Let me first state that disabling the route cache hash rebuild
should not be done without extensive analysis on the risk profile
and careful deliberation.

However, there are times when this can be done safely or for
testing.  For example, when you have mechanisms for ensuring
that offending parties do not exist in your network.

This patch lets the user disable the rebuild if the interval is
set to zero.  This also incidentally fixes a divide-by-zero error
with name-spaces.

In addition, this patch makes the effect of an interval change
immediate rather than it taking effect at the next rebuild as
is currently the case.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Noticed by Paulius Zaleckas.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch replaces dst_metric() with dst_mtu() in net/ipv4/route.c.
Signed-off-by: NRami Rosen <ramirose@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

fix:

net/ipv4/route.c: In function 'ip_static_sysctl_init':
net/ipv4/route.c:3225: error: 'ipv4_route_path' undeclared (first use in this function)
net/ipv4/route.c:3225: error: (Each undeclared identifier is reported only once
net/ipv4/route.c:3225: error: for each function it appears in.)
net/ipv4/route.c:3225: error: 'ipv4_route_table' undeclared (first use in this function)
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Piss-poor sysctl registration API strikes again, film at 11...

What we really need is _pathname_ required to be present in already
registered table, so that kernel could warn about bad order.  That's the
next target for sysctl stuff (and generally saner and more explicit
order of initialization of ipv[46] internals wouldn't hurt either).

For the time being, here are full fixups required by ..._rotable()
stuff; we make per-net sysctl sets descendents of "ro" one and make sure
that sufficient skeleton is there before we start registering per-net
sysctls.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Piss-poor sysctl registration API strikes again, film at 11...
What we really need is _pathname_ required to be present in
already registered table, so that kernel could warn about bad
order.  That's the next target for sysctl stuff (and generally
saner and more explicit order of initialization of ipv[46]
internals wouldn't hurt either).

For the time being, here are full fixups required by ..._rotable()
stuff; we make per-net sysctl sets descendents of "ro" one and
make sure that sufficient skeleton is there before we start registering
per-net sysctls.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Running recent kernels, and using a particular vpn gateway, I've been
having to edit my mails down to get them accepted by the smtp server.

Git bisect led to commit e84f84f2 -
netns: place rt_genid into struct net.  The conversion from a != test
to rt_is_expired() put one negative too many: and now my mail works.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Acked-by: NDenis V. Lunev <den@openvz.org>
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>

It is possible to avoid locking at all in ipv4_sysctl_rtcache_flush by
defining local ctl_table on the stack.

The patch is based on the suggestion from Eric W. Biederman.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

dst cache is marked as expired on the per/namespace basis by previous
path. Right now we have to implement selective cache shrinking. This
procedure has been ported from older OpenVz codebase.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Basically, there is no difference to atomic_read internally or pass it as
a parameter as rt_hash is inline.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

flush delay is used as an external storage for net.ipv4.route.flush sysctl
entry. It is write-only.

The ctl_table->data for this entry is used once. Fix this case to point
to the stack to remove global variable. Do this to avoid additional
variable on struct net in the next patch.

Possible race (as it was before) accessing this local variable is removed
using flush_mutex.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes CVS keywords that weren't updated for a long time
from comments.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Also removes an obsolete check for the unused flag RTCF_MASQ.
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Because the IPsec output function xfrm_output_resume does its
own dst_output call it should always call __ip_local_output
instead of ip_local_output as the latter may invoke dst_output
directly.  Otherwise the return values from nf_hook and dst_output
may clash as they both use the value 1 but for different purposes.

When that clash occurs this can cause a packet to be used after
it has been freed which usually leads to a crash.  Because the
offending value is only returned from dst_output with qdiscs
such as HTB, this bug is normally not visible.

Thanks to Marco Berizzi for his perseverance in tracking this
down.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are functions to refer to the value of dst->metric[THE_METRIC-1]
directly without use of a inline function "dst_metric" defined in
net/dst.h.

The following patch changes them to use the inline function
consistently.
Signed-off-by: NSatoru SATOH <satoru.satoh@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NSatoru SATOH <satoru.satoh@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add struct net_device parameter to ip_rt_frag_needed() and update MTU to
cache entries where ifindex is specified. This is similar to what is
already done in ip_rt_redirect().
Signed-off-by: NTimo Teras <timo.teras@iki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Plan C: we can follow the Al Viro's proposal about %n like in this patch.
The same applies to udp, fib (the /proc/net/route file), rt_cache and 
sctp debug. This is minus ~150-200 bytes for each.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

And use %u to format port.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The comparison in ip_route_input is a hot path, by recoding the C
"and" as bit operations, fewer conditional branches get generated
so the code should be faster. Maybe someday Gcc will be smart
enough to do this?
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Acked-by: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No urgency on the rehash interval timer, so mark it as deferrable.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since route hash is a triple, use jhash_3words rather doing the mixing
directly. This should be as fast and give better distribution.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't mark functions that are large as inline, let compiler decide.
Also, use inline rather than __inline__.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce an inline net_eq() to compare two namespaces.
Without CONFIG_NET_NS, since no namespace other than &init_net
exists, it is always 1.

We do not need to convert 1) inline vs inline and
2) inline vs &init_net comparisons.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

Without CONFIG_NET_NS, no namespace other than &init_net exists,
no need to store net in seq_net_private.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

Introduce per-sock inlines: sock_net(), sock_net_set()
and per-inet_timewait_sock inlines: twsk_net(), twsk_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

Introduce per-net_device inlines: dev_net(), dev_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

The route table parameters are set based on system memory and sysctl
values that almost never change. Also the genid only changes every
10 minutes.

RTprint is defined by never used.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Just remove it.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

(Anonymous) unions can help us to avoid ugly casts.

A common cast it the (struct rtable *)skb->dst one.

Defining an union like  :
union {
     struct dst_entry *dst;
     struct rtable *rtable;
};
permits to use skb->rtable in place.
Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>