Commit Graph

524 Commits

Author SHA1 Message Date
Christoph Lameter 3ed66e910c net: replace __this_cpu_inc in route.c with raw_cpu_inc
The RT_CACHE_STAT_INC macro triggers the new preemption checks
for __this_cpu ops.

I do not see any other synchronization that would allow the use of a
__this_cpu operation here however in commit dbd2915ce8 ("[IPV4]:
RT_CACHE_STAT_INC() warning fix") Andrew justifies the use of
raw_smp_processor_id() here because "we do not care" about races.  In
the past we agreed that the price of disabling interrupts here to get
consistent counters would be too high.  These counters may be inaccurate
due to race conditions.

The use of __this_cpu op improves the situation already from what commit
dbd2915ce8 did since the single instruction emitted on x86 does not
allow the race to occur anymore.  However, non x86 platforms could still
experience a race here.

Trace:

  __this_cpu_add operation in preemptible [00000000] code: avahi-daemon/1193
  caller is __this_cpu_preempt_check+0x38/0x60
  CPU: 1 PID: 1193 Comm: avahi-daemon Tainted: GF            3.12.0-rc4+ #187
  Call Trace:
    check_preemption_disabled+0xec/0x110
    __this_cpu_preempt_check+0x38/0x60
    __ip_route_output_key+0x575/0x8c0
    ip_route_output_flow+0x27/0x70
    udp_sendmsg+0x825/0xa20
    inet_sendmsg+0x85/0xc0
    sock_sendmsg+0x9c/0xd0
    ___sys_sendmsg+0x37c/0x390
    __sys_sendmsg+0x49/0x90
    SyS_sendmsg+0x12/0x20
    tracesys+0xe1/0xe6

Signed-off-by: Christoph Lameter <cl@linux.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:36:14 -07:00
Li RongQing 0b8c7f6f2a ipv4: remove ip_rt_dump from route.c
ip_rt_dump do nothing after IPv4 route caches removal, so we can remove it.

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-24 12:45:01 -04:00
Li RongQing 4a4eb21fd6 ipv4: remove ipv4_ifdown_dst from route.c
ipv4_ifdown_dst does nothing after IPv4 route caches removal,
so we can remove it.

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-24 00:18:44 -04:00
David S. Miller 1e8d6421cf Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/bonding/bond_3ad.h
	drivers/net/bonding/bond_main.c

Two minor conflicts in bonding, both of which were overlapping
changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-19 01:24:22 -05:00
Duan Jiong a6254864c0 ipv4: fix counter in_slow_tot
since commit 89aef8921bf("ipv4: Delete routing cache."), the counter
in_slow_tot can't work correctly.

The counter in_slow_tot increase by one when fib_lookup() return successfully
in ip_route_input_slow(), but actually the dst struct maybe not be created and
cached, so we can increase in_slow_tot after the dst struct is created.

Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-17 16:54:42 -05:00
Duan Jiong cd0f0b95fd ipv4: distinguish EHOSTUNREACH from the ENETUNREACH
since commit 251da413("ipv4: Cache ip_error() routes even when not forwarding."),
the counter IPSTATS_MIB_INADDRERRORS can't work correctly, because the value of
err was always set to ENETUNREACH.

Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-16 23:45:31 -05:00
stephen hemminger 2045ceaed4 net: remove unnecessary return's
One of my pet coding style peeves is the practice of
adding extra return; at the end of function.
Kill several instances of this in network code.

I suppose some coccinelle wizardy could do this automatically.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13 18:33:38 -05:00
Hannes Frederic Sowa f87c10a8aa ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against pmtu spoofing
While forwarding we should not use the protocol path mtu to calculate
the mtu for a forwarded packet but instead use the interface mtu.

We mark forwarded skbs in ip_forward with IPSKB_FORWARDED, which was
introduced for multicast forwarding. But as it does not conflict with
our usage in unicast code path it is perfect for reuse.

I moved the functions ip_sk_accept_pmtu, ip_sk_use_pmtu and ip_skb_dst_mtu
along with the new ip_dst_mtu_maybe_forward to net/ip.h to fix circular
dependencies because of IPSKB_FORWARDED.

Because someone might have written a software which does probe
destinations manually and expects the kernel to honour those path mtus
I introduced a new per-namespace "ip_forward_use_pmtu" knob so someone
can disable this new behaviour. We also still use mtus which are locked on a
route for forwarding.

The reason for this change is, that path mtus information can be injected
into the kernel via e.g. icmp_err protocol handler without verification
of local sockets. As such, this could cause the IPv4 forwarding path to
wrongfully emit fragmentation needed notifications or start to fragment
packets along a path.

Tunnel and ipsec output paths clear IPCB again, thus IPSKB_FORWARDED
won't be set and further fragmentation logic will use the path mtu to
determine the fragmentation size. They also recheck packet size with
help of path mtu discovery and report appropriate errors.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: John Heffner <johnwheffner@gmail.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13 11:22:54 -08:00
Alexei Starovoitov dcdfdf56b4 ipv4: fix race in concurrent ip_route_input_slow()
CPUs can ask for local route via ip_route_input_noref() concurrently.
if nh_rth_input is not cached yet, CPUs will proceed to allocate
equivalent DSTs on 'lo' and then will try to cache them in nh_rth_input
via rt_cache_route()
Most of the time they succeed, but on occasion the following two lines:
	orig = *p;
	prev = cmpxchg(p, orig, rt);
in rt_cache_route() do race and one of the cpus fails to complete cmpxchg.
But ip_route_input_slow() doesn't check the return code of rt_cache_route(),
so dst is leaking. dst_destroy() is never called and 'lo' device
refcnt doesn't go to zero, which can be seen in the logs as:
	unregister_netdevice: waiting for lo to become free. Usage count = 1
Adding mdelay() between above two lines makes it easily reproducible.
Fix it similar to nh_pcpu_rth_output case.

Fixes: d2d68ba9fe ("ipv4: Cache input routes in fib_info nexthops.")
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-20 15:28:44 -05:00
Hannes Frederic Sowa 482fc6094a ipv4: introduce new IP_MTU_DISCOVER mode IP_PMTUDISC_INTERFACE
Sockets marked with IP_PMTUDISC_INTERFACE won't do path mtu discovery,
their sockets won't accept and install new path mtu information and they
will always use the interface mtu for outgoing packets. It is guaranteed
that the packet is not fragmented locally. But we won't set the DF-Flag
on the outgoing frames.

Florian Weimer had the idea to use this flag to ensure DNS servers are
never generating outgoing fragments. They may well be fragmented on the
path, but the server never stores or usees path mtu values, which could
well be forged in an attack.

(The root of the problem with path MTU discovery is that there is
no reliable way to authenticate ICMP Fragmentation Needed But DF Set
messages because they are sent from intermediate routers with their
source addresses, and the IMCP payload will not always contain sufficient
information to identify a flow.)

Recent research in the DNS community showed that it is possible to
implement an attack where DNS cache poisoning is feasible by spoofing
fragments. This work was done by Amir Herzberg and Haya Shulman:
<https://sites.google.com/site/hayashulman/files/fragmentation-poisoning.pdf>

This issue was previously discussed among the DNS community, e.g.
<http://www.ietf.org/mail-archive/web/dnsext/current/msg01204.html>,
without leading to fixes.

This patch depends on the patch "ipv4: fix DO and PROBE pmtu mode
regarding local fragmentation with UFO/CORK" for the enforcement of the
non-fragmentable checks. If other users than ip_append_page/data should
use this semantic too, we have to add a new flag to IPCB(skb)->flags to
suppress local fragmentation and check for this in ip_finish_output.

Many thanks to Florian Weimer for the idea and feedback while implementing
this patch.

Cc: David S. Miller <davem@davemloft.net>
Suggested-by: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-05 21:52:27 -05:00
Eric Dumazet 0baf2b35fc ipv4: shrink rt_cache_stat
Half of the rt_cache_stat fields are no longer used after IP
route cache removal, lets shrink this per cpu area.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-17 16:11:04 -04:00
Jiri Benc 0a7e226090 ipv4: fix ineffective source address selection
When sending out multicast messages, the source address in inet->mc_addr is
ignored and rewritten by an autoselected one. This is caused by a typo in
commit 813b3b5db8 ("ipv4: Use caller's on-stack flowi as-is in output
route lookups").

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-07 15:26:46 -04:00
Eric Dumazet 734d2725db ipv4: raise IP_MAX_MTU to theoretical limit
As discussed last year [1], there is no compelling reason
to limit IPv4 MTU to 0xFFF0, while real limit is 0xFFFF

[1] : http://marc.info/?l=linux-netdev&m=135607247609434&w=2

Willem raised this issue again because some of our internal
regression tests broke after lo mtu being set to 65536.

IP_MTU reports 0xFFF0, and the test attempts to send a RAW datagram of
mtu + 1 bytes, expecting the send() to fail, but it does not.

Alexey raised interesting points about TCP MSS, that should be addressed
in follow-up patches in TCP stack if needed, as someone could also set
an odd mtu anyway.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-20 15:05:04 -07:00
fan.du ca4c3fc24e net: split rt_genid for ipv4 and ipv6
Current net name space has only one genid for both IPv4 and IPv6, it has below
drawbacks:

- Add/delete an IPv4 address will invalidate all IPv6 routing table entries.
- Insert/remove XFRM policy will also invalidate both IPv4/IPv6 routing table
  entries even when the policy is only applied for one address family.

Thus, this patch attempt to split one genid for two to cater for IPv4 and IPv6
separately in a fine granularity.

Signed-off-by: Fan Du <fan.du@windriver.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-31 14:56:36 -07:00
Timo Teräs 2ffae99d1f ipv4: use next hop exceptions also for input routes
Commit d2d68ba9 (ipv4: Cache input routes in fib_info nexthops)
assmued that "locally destined, and routed packets, never trigger
PMTU events or redirects that will be processed by us".

However, it seems that tunnel devices do trigger PMTU events in certain
cases. At least ip_gre, ip6_gre, sit, and ipip do use the inner flow's
skb_dst(skb)->ops->update_pmtu to propage mtu information from the
outer flows. These can cause the inner flow mtu to be decreased. If
next hop exceptions are not consulted for pmtu, IP fragmentation will
not be done properly for these routes.

It also seems that we really need to have the PMTU information always
for netfilter TCPMSS clamp-to-pmtu feature to work properly.

So for the time being, cache separate copies of input routes for
each next hop exception.

Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-28 21:27:47 -07:00
Joe Perches fe2c6338fd net: Convert uses of typedef ctl_table to struct ctl_table
Reduce the uses of this unnecessary typedef.

Done via perl script:

$ git grep --name-only -w ctl_table net | \
  xargs perl -p -i -e '\
	sub trim { my ($local) = @_; $local =~ s/(^\s+|\s+$)//g; return $local; } \
        s/\b(?<!struct\s)ctl_table\b(\s*\*\s*|\s+\w+)/"struct ctl_table " . trim($1)/ge'

Reflow the modified lines that now exceed 80 columns.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-13 02:36:09 -07:00
David S. Miller 6bc19fb82d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merge 'net' bug fixes into 'net-next' as we have patches
that will build on top of them.

This merge commit includes a change from Emil Goode
(emilgoode@gmail.com) that fixes a warning that would
have been introduced by this merge.  Specifically it
fixes the pingv6_ops method ipv6_chk_addr() to add a
"const" to the "struct net_device *dev" argument and
likewise update the dummy_ipv6_chk_addr() declaration.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-05 16:37:30 -07:00
Timo Teräs 5aad1de5ea ipv4: use separate genid for next hop exceptions
commit 13d82bf5 (ipv4: Fix flushing of cached routing informations)
added the support to flush learned pmtu information.

However, using rt_genid is quite heavy as it is bumped on route
add/change and multicast events amongst other places. These can
happen quite often, especially if using dynamic routing protocols.

While this is ok with routes (as they are just recreated locally),
the pmtu information is learned from remote systems and the icmp
notification can come with long delays. It is worthy to have separate
genid to avoid excessive pmtu resets.

Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-03 00:07:43 -07:00
Timo Teräs f016229e30 ipv4: rate limit updating of next hop exceptions with same pmtu
The tunnel devices call update_pmtu for each packet sent, this causes
contention on the fnhe_lock. Ignore the pmtu update if pmtu is not
actually changed, and there is still plenty of time before the entry
expires.

Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-03 00:07:43 -07:00
Timo Teräs 387aa65a89 ipv4: properly refresh rtable entries on pmtu/redirect events
This reverts commit 05ab86c5 (xfrm4: Invalidate all ipv4 routes on
IPsec pmtu events). Flushing all cached entries is not needed.

Instead, invalidate only the related next hop dsts to recheck for
the added next hop exception where needed. This also fixes a subtle
race due to bumping generation id's before updating the pmtu.

Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-03 00:07:42 -07:00
Michal Kubecek f96ef988cc ipv4: fix redirect handling for TCP packets
Unlike ipv4_redirect() and ipv4_sk_redirect(), ip_do_redirect()
doesn't call __build_flow_key() directly but via
ip_rt_build_flow_key() wrapper. This leads to __build_flow_key()
getting pointer to IPv4 header of the ICMP redirect packet
rather than pointer to the embedded IPv4 header of the packet
initiating the redirect.

As a result, handling of ICMP redirects initiated by TCP packets
is broken. Issue was introduced by

	4895c771c ("ipv4: Add FIB nexthop exceptions.")

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-27 23:39:19 -07:00
Thomas Graf 661d2967b3 rtnetlink: Remove passing of attributes into rtnl_doit functions
With decnet converted, we can finally get rid of rta_buf and its
computations around it. It also gets rid of the minimal header
length verification since all message handlers do that explicitly
anyway.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-22 10:31:16 -04:00
Gao feng 082c7ca42b net: ipv4: fix waring -Wunused-variable
the vars ip_rt_gc_timeout is used only when
CONFIG_SYSCTL is selected.

move these vars into CONFIG_SYSCTL.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-19 13:18:13 -05:00
Gao feng d4beaa66ad net: proc: change proc_net_fops_create to proc_create
Right now, some modules such as bonding use proc_create
to create proc entries under /proc/net/, and other modules
such as ipv4 use proc_net_fops_create.

It looks a little chaos.this patch changes all of
proc_net_fops_create to proc_create. we can remove
proc_net_fops_create after this patch.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-18 14:53:08 -05:00
Steffen Klassert b44108dbdb ipv4: Fix route refcount on pmtu discovery
git commit 9cb3a50c (ipv4: Invalidate the socket cached route on
pmtu events if possible) introduced a refcount problem. We don't
get a refcount on the route if we get it from__sk_dst_get(), but
we need one if we want to reuse this route because __sk_dst_set()
releases the refcount of the old route. This patch adds proper
refcount handling for that case. We introduce a 'new' flag to
indicate that we are going to use a new route and we release the
old route only if we replace it by a new one.

Reported-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-22 14:23:17 -05:00
Steffen Klassert 9cb3a50c5f ipv4: Invalidate the socket cached route on pmtu events if possible
The route lookup in ipv4_sk_update_pmtu() might return a route
different from the route we cached at the socket. This is because
standart routes are per cpu, so each cpu has it's own struct rtable.
This means that we do not invalidate the socket cached route if the
NET_RX_SOFTIRQ is not served by the same cpu that the sending socket
uses. As a result, the cached route reused until we disconnect.

With this patch we invalidate the socket cached route if possible.
If the socket is owened by the user, we can't update the cached
route directly. A followup patch will implement socket release
callback functions for datagram sockets to handle this case.

Reported-by: Yurij M. Plotnikov <Yurij.Plotnikov@oktetlabs.ru>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-21 14:17:05 -05:00
Steffen Klassert fa1e492aa3 ipv4: Don't update the pmtu on mtu locked routes
Routes with locked mtu should not use learned pmtu informations,
so do not update the pmtu on these routes.

Reported-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-17 03:39:36 -05:00
Steffen Klassert 38d523e294 ipv4: Remove output route check in ipv4_mtu
The output route check was introduced with git commit 261663b0
(ipv4: Don't use the cached pmtu informations for input routes)
during times when we cached the pmtu informations on the
inetpeer. Now the pmtu informations are back in the routes,
so this check is obsolete. It also had some unwanted side effects,
as reported by Timo Teras and Lukas Tribus.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-17 03:39:36 -05:00
Nicolas Dichtel 8caaf7b608 ipv4/route/rtnl: get mcast attributes when dst is multicast
Commit f1ce3062c5 (ipv4: Remove 'rt_dst' from 'struct rtable') removes the
call to ipmr_get_route(), which will get multicast parameters of the route.

I revert the part of the patch that remove this call. I think the goal was only
to get rid of rt_dst field.

The patch is only compiled-tested. My first idea was to remove ipmr_get_route()
because rt_fill_info() was the only user, but it seems the previous patch cleans
the code a bit too much ;-)

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-07 12:24:33 -05:00
David S. Miller 24bc518a68 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/wireless/iwlwifi/pcie/tx.c

Minor iwlwifi conflict in TX queue disabling between 'net', which
removed a bogus warning, and 'net-next' which added some status
register poking code.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-25 12:49:17 -05:00
Julian Anastasov 636174219b ipv4: do not cache looped multicasts
Starting from 3.6 we cache output routes for
multicasts only when using route to 224/4. For local receivers
we can set RTCF_LOCAL flag depending on the membership but
in such case we use maddr and saddr which are not caching
keys as before. Additionally, we can not use same place to
cache routes that differ in RTCF_LOCAL flag value.

	Fix it by caching only RTCF_MULTICAST entries
without RTCF_LOCAL (send-only, no loopback). As a side effect,
we avoid unneeded lookup for fnhe when not caching because
multicasts are not redirected and they do not learn PMTU.

	Thanks to Maxime Bizon for showing the caching
problems in __mkroute_output for 3.6 kernels: different
RTCF_LOCAL flag in cache can lead to wrong ip_mc_output or
ip_output call and the visible problem is that traffic can
not reach local receivers via loopback.

Reported-by: Maxime Bizon <mbizon@freebox.fr>
Tested-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-22 16:06:49 -05:00
Eric W. Biederman 464dc801c7 net: Don't export sysctls to unprivileged users
In preparation for supporting the creation of network namespaces
by unprivileged users, modify all of the per net sysctl exports
and refuse to allow them to unprivileged users.

This makes it safe for unprivileged users in general to access
per net sysctls, and allows sysctls to be exported to unprivileged
users on an individual basis as they are deemed safe.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-18 20:30:55 -05:00
Steffen Klassert 703fb94ec5 xfrm: Fix the gc threshold value for ipv4
The xfrm gc threshold value depends on ip_rt_max_size. This
value was set to INT_MAX with the routing cache removal patch,
so we start doing garbage collecting when we have INT_MAX/2
IPsec routes cached. Fix this by going back to the static
threshold of 1024 routes.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2012-11-13 09:15:07 +01:00
Steffen Klassert 13d82bf50d ipv4: Fix flushing of cached routing informations
Currently we can not flush cached pmtu/redirect informations via
the ipv4_sysctl_rtcache_flush sysctl. We need to check the rt_genid
of the old route and reset the nh exeption if the old route is
expired when we bind a new route to a nh exeption.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-18 15:34:30 -04:00
stephen hemminger 68aaed54e7 ipv4: fix route mark sparse warning
Sparse complains about RTA_MARK which is should be host order according
to include file and usage in iproute.

net/ipv4/route.c:2223:46: warning: incorrect type in argument 3 (different base types)
net/ipv4/route.c:2223:46:    expected restricted __be32 [usertype] value
net/ipv4/route.c:2223:46:    got unsigned int [unsigned] [usertype] flowic_mark

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-10 22:54:59 -04:00
Julian Anastasov c92b96553a ipv4: Add FLOWI_FLAG_KNOWN_NH
Add flag to request that output route should be
returned with known rt_gateway, in case we want to use
it as nexthop for neighbour resolving.

	The returned route can be cached as follows:

- in NH exception: because the cached routes are not shared
	with other destinations
- in FIB NH: when using gateway because all destinations for
	NH share same gateway

	As last option, to return rt_gateway!=0 we have to
set DST_NOCACHE.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08 17:42:36 -04:00
Julian Anastasov 155e8336c3 ipv4: introduce rt_uses_gateway
Add new flag to remember when route is via gateway.
We will use it to allow rt_gateway to contain address of
directly connected host for the cases when DST_NOCACHE is
used or when the NH exception caches per-destination route
without DST_NOCACHE flag, i.e. when routes are not used for
other destinations. By this way we force the neighbour
resolving to work with the routed destination but we
can use different address in the packet, feature needed
for IPVS-DR where original packet for virtual IP is routed
via route to real IP.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08 17:42:36 -04:00
Julian Anastasov f8a17175c6 ipv4: make sure nh_pcpu_rth_output is always allocated
Avoid checking nh_pcpu_rth_output in fast path,
abort fib_info creation on alloc_percpu failure.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08 17:42:35 -04:00
Julian Anastasov e81da0e113 ipv4: fix sending of redirects
After "Cache input routes in fib_info nexthops" (commit
d2d68ba9fe) and "Elide fib_validate_source() completely when possible"
(commit 7a9bc9b81a) we can not send ICMP redirects. It seems we
should not cache the RTCF_DOREDIRECT flag in nh_rth_input because
the same fib_info can be used for traffic that is not redirected,
eg. from other input devices or from sources that are not in same subnet.

	As result, we have to disable the caching of RTCF_DOREDIRECT
flag and to force source validation for the case when forwarding
traffic to the input device. If traffic comes from directly connected
source we allow redirection as it was done before both changes.

	Avoid setting RTCF_DOREDIRECT if IN_DEV_TX_REDIRECTS
is disabled, this can avoid source address validation and to
help caching the routes.

	After the change "Adjust semantics of rt->rt_gateway"
(commit f8126f1d51) we should make sure our ICMP_REDIR_HOST messages
contain daddr instead of 0.0.0.0 when target is directly connected.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08 17:42:35 -04:00
Steffen Klassert ee9a8f7ab2 ipv4: Don't report stale pmtu values to userspace
We report cached pmtu values even if they are already expired.
Change this to not report these values after they are expired
and fix a race in the expire time calculation, as suggested by
Eric Dumazet.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08 14:46:35 -04:00
Steffen Klassert 7f92d334ba ipv4: Don't create nh exeption when the device mtu is smaller than the reported pmtu
When a local tool like tracepath tries to send packets bigger than
the device mtu, we create a nh exeption and set the pmtu to device
mtu. The device mtu does not expire, so check if the device mtu is
smaller than the reported pmtu and don't crerate a nh exeption in
that case.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08 14:46:35 -04:00
Steffen Klassert d851c12b60 ipv4: Always invalidate or update the route on pmtu events
Some protocols, like IPsec still cache routes. So we need to invalidate
the old route on pmtu events to avoid the reuse of stale routes.
We also need to update the mtu and expire time of the route if we already
use a nh exception route, otherwise we ignore newly learned pmtu values
after the first expiration.

With this patch we always invalidate or update the route on pmtu events.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08 14:46:34 -04:00
David S. Miller 6a06e5e1bb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/team/team.c
	drivers/net/usb/qmi_wwan.c
	net/batman-adv/bat_iv_ogm.c
	net/ipv4/fib_frontend.c
	net/ipv4/route.c
	net/l2tp/l2tp_netlink.c

The team, fib_frontend, route, and l2tp_netlink conflicts were simply
overlapping changes.

qmi_wwan and bat_iv_ogm were of the "use HEAD" variety.

With help from Antonio Quartulli.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-28 14:40:49 -04:00
Nicolas Dichtel b42664f898 netns: move net->ipv4.rt_genid to net->rt_genid
This commit prepares the use of rt_genid by both IPv4 and IPv6.
Initialization is left in IPv4 part.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-18 15:57:03 -04:00
Eric Dumazet 2885da7296 net: rt_cache_flush() cleanup
We dont use jhash anymore since route cache removal,
so we can get rid of get_random_bytes() calls for rt_genid
changes.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-18 15:54:19 -04:00
Nicolas Dichtel bafa6d9d89 ipv4/route: arg delay is useless in rt_cache_flush()
Since route cache deletion (89aef8921b), delay is no
more used. Remove it.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-18 15:44:34 -04:00
Eric W. Biederman 15e473046c netlink: Rename pid to portid to avoid confusion
It is a frequent mistake to confuse the netlink port identifier with a
process identifier.  Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.

I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.

I have successfully built an allyesconfig kernel with this change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-10 15:30:41 -04:00
Eric Dumazet ba8bd0ea98 net: rt_cache_flush() cleanup
We dont use jhash anymore since route cache removal,
so we can get rid of get_random_bytes() calls for rt_genid
changes.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-07 17:23:17 -04:00
Nicolas Dichtel 4ccfe6d410 ipv4/route: arg delay is useless in rt_cache_flush()
Since route cache deletion (89aef8921b), delay is no
more used. Remove it.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-07 14:44:08 -04:00
Alexander Duyck 98d75c3724 ipv4: Minor logic clean-up in ipv4_mtu
In ipv4_mtu there is some logic where we are testing for a non-zero value
and a timer expiration, then setting the value to zero, and then testing if
the value is zero we set it to a value based on the dst.  Instead of
bothering with the extra steps it is easier to just cleanup the logic so
that we set it to the dst based value if it is zero or if the timer has
expired.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
2012-08-31 16:22:50 -04:00