On a box with most of the optional Netfilter switches turned off some
of the NLAs are never send, e. g. secmark, mark or the conntrack
byte/packet counters. As a worst case scenario this may possibly
still lead to ctnetlink skbs being reallocated in netlink_trim()
later, loosing all the nice effects from the previous patches.
I try to solve that (at least partly) by correctly #ifdef'ing the
NLAs in the computation.
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Usefull for all protocols which do not add additional data, such
as GRE or UDPlite.
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Try to allocate a Netlink skb roughly the size of the actual
message, with the help from the l3 and l4 protocol helpers.
This is all to prevent a reallocation in netlink_trim() later.
The overhead of allocating the right-sized skb is rather small, with
ctnetlink_alloc_skb() actually being inlined away on my x86_64 box.
The size of the per-proto space is determined at registration time of
the protocol helper.
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Use "hlist_nulls" infrastructure we added in 2.6.29 for RCUification of UDP & TCP.
This permits an easy conversion from call_rcu() based hash lists to a
SLAB_DESTROY_BY_RCU one.
Avoiding call_rcu() delay at nf_conn freeing time has numerous gains.
First, it doesnt fill RCU queues (up to 10000 elements per cpu).
This reduces OOM possibility, if queued elements are not taken into account
This reduces latency problems when RCU queue size hits hilimit and triggers
emergency mode.
- It allows fast reuse of just freed elements, permitting better use of
CPU cache.
- We delete rcu_head from "struct nf_conn", shrinking size of this structure
by 8 or 16 bytes.
This patch only takes care of "struct nf_conn".
call_rcu() is still used for less critical conntrack parts, that may
be converted later if necessary.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This is necessary in order to have an upper bound for Netlink
message calculation, which is not a problem at all, as there
are no helpers with a longer name.
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
There is added a single callback for the l3 proto helper. The two
callbacks for the l4 protos are necessary because of the general
structure of a ctnetlink event, which is in short:
CTA_TUPLE_ORIG
<l3/l4-proto-attributes>
CTA_TUPLE_REPLY
<l3/l4-proto-attributes>
CTA_ID
...
CTA_PROTOINFO
<l4-proto-attributes>
CTA_TUPLE_MASTER
<l3/l4-proto-attributes>
Therefore the formular is
size := sizeof(generic-nlas) + 3 * sizeof(tuple_nlas) + sizeof(protoinfo_nlas)
Some of the NLAs are optional, e. g. CTA_TUPLE_MASTER, which is only
set if it's an expected connection. But the number of optional NLAs is
small enough to prevent netlink_trim() from reallocating if calculated
properly.
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
We use same not trivial helper function in four places. We can factorize it.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Using hlist_add_head() in nf_conntrack_set_hashsize() is quite dangerous.
Without any barrier, one CPU could see a loop while doing its lookup.
Its true new table cannot be seen by another cpu, but previous table is still
readable.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
net/netfilter/xt_LED.c:40: error: field netfilter_led_trigger has incomplete type
net/netfilter/xt_LED.c: In function led_timeout_callback:
net/netfilter/xt_LED.c:78: warning: unused variable ledinternal
net/netfilter/xt_LED.c: In function led_tg_check:
net/netfilter/xt_LED.c:102: error: implicit declaration of function led_trigger_register
net/netfilter/xt_LED.c: In function led_tg_destroy:
net/netfilter/xt_LED.c:135: error: implicit declaration of function led_trigger_unregister
Fix by adding a dependency on LED_TRIGGERS.
Reported-by: Sachin Sant <sachinp@in.ibm.com>
Tested-by: Subrata Modak <tosubrata@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch combines Greg Bank's dprintk() work with the existing dynamic
printk patchset, we are now calling it 'dynamic debug'.
The new feature of this patchset is a richer /debugfs control file interface,
(an example output from my system is at the bottom), which allows fined grained
control over the the debug output. The output can be controlled by function,
file, module, format string, and line number.
for example, enabled all debug messages in module 'nf_conntrack':
echo -n 'module nf_conntrack +p' > /mnt/debugfs/dynamic_debug/control
to disable them:
echo -n 'module nf_conntrack -p' > /mnt/debugfs/dynamic_debug/control
A further explanation can be found in the documentation patch.
Signed-off-by: Greg Banks <gnb@sgi.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We use RCU to defer freeing of conntrack structures. In DOS situation, RCU might
accumulate about 10.000 elements per CPU in its internal queues. To get accurate
conntrack counts (at the expense of slightly more RAM used), we might consider
conntrack counter not taking into account "about to be freed elements, waiting
in RCU queues". We thus decrement it in nf_conntrack_free(), not in the RCU
callback.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Tested-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch fixes an unaligned memory access in tcp_sack while reading
sequence numbers from TCP selective acknowledgement options. Prior to
applying this patch, upstream linux-2.6.27.20 was occasionally
generating messages like this on my sparc64 system:
[54678.532071] Kernel unaligned access at TPC[6b17d4] tcp_packet+0xcd4/0xd00
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch adds nfnetlink_set_err() to propagate the error to netlink
broadcast listener in case of memory allocation errors in the
message building.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patchs adds support of modification of the used logger via sysctl.
It can be used to change the logger to module that can not use the bind
operation (ipt_LOG and ipt_ULOG). For this purpose, it creates a
directory /proc/sys/net/netfilter/nf_log which contains a file
per-protocol. The content of the file is the name current logger (NONE if
not set) and a logger can be setup by simply echoing its name to the file.
By echoing "NONE" to a /proc/sys/net/netfilter/nf_log/PROTO file, the
logger corresponding to this PROTO is set to NULL.
Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Convert the remaining refcount users.
As pointed out by Patrick McHardy, the protocols can be accessed safely using RCU.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch adds the iptables cluster match. This match can be used
to deploy gateway and back-end load-sharing clusters. The cluster
can be composed of 32 nodes maximum (although I have only tested
this with two nodes, so I cannot tell what is the real scalability
limit of this solution in terms of cluster nodes).
Assuming that all the nodes see all packets (see below for an
example on how to do that if your switch does not allow this), the
cluster match decides if this node has to handle a packet given:
(jhash(source IP) % total_nodes) & node_mask
For related connections, the master conntrack is used. The following
is an example of its use to deploy a gateway cluster composed of two
nodes (where this is the node 1):
iptables -I PREROUTING -t mangle -i eth1 -m cluster \
--cluster-total-nodes 2 --cluster-local-node 1 \
--cluster-proc-name eth1 -j MARK --set-mark 0xffff
iptables -A PREROUTING -t mangle -i eth1 \
-m mark ! --mark 0xffff -j DROP
iptables -A PREROUTING -t mangle -i eth2 -m cluster \
--cluster-total-nodes 2 --cluster-local-node 1 \
--cluster-proc-name eth2 -j MARK --set-mark 0xffff
iptables -A PREROUTING -t mangle -i eth2 \
-m mark ! --mark 0xffff -j DROP
And the following commands to make all nodes see the same packets:
ip maddr add 01:00:5e:00:01:01 dev eth1
ip maddr add 01:00:5e:00:01:02 dev eth2
arptables -I OUTPUT -o eth1 --h-length 6 \
-j mangle --mangle-mac-s 01:00:5e:00:01:01
arptables -I INPUT -i eth1 --h-length 6 \
--destination-mac 01:00:5e:00:01:01 \
-j mangle --mangle-mac-d 00:zz:yy:xx:5a:27
arptables -I OUTPUT -o eth2 --h-length 6 \
-j mangle --mangle-mac-s 01:00:5e:00:01:02
arptables -I INPUT -i eth2 --h-length 6 \
--destination-mac 01:00:5e:00:01:02 \
-j mangle --mangle-mac-d 00:zz:yy:xx:5a:27
In the case of TCP connections, pickup facility has to be disabled
to avoid marking TCP ACK packets coming in the reply direction as
valid.
echo 0 > /proc/sys/net/netfilter/nf_conntrack_tcp_loose
BTW, some final notes:
* This match mangles the skbuff pkt_type in case that it detects
PACKET_MULTICAST for a non-multicast address. This may be done in
a PKTTYPE target for this sole purpose.
* This match supersedes the CLUSTERIP target.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Module specific data moved into per-net site and being allocated/freed
during net namespace creation/deletion.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
We currently use the negative value in the conntrack code to encode
the packet verdict in the error. As NF_DROP is equal to 0, inverting
NF_DROP makes no sense and, as a result, no packets are ever dropped.
Signed-off-by: Christoph Paasch <christoph.paasch@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch fixes a possible crash due to the missing initialization
of the expectation class when nf_ct_expect_related() is called.
Reported-by: BORBELY Zoltan <bozo@andrews.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Commit 784544739a (netfilter: iptables:
lock free counters) broke a number of modules whose rule data referenced
itself. A reallocation would not reestablish the correct references, so
it is best to use a separate struct that does not fall under RCU.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch moves the event reporting outside the lock section. With
this patch, the creation and update of entries is homogeneous from
the event reporting perspective. Moreover, as the event reporting is
done outside the lock section, the netlink broadcast delivery can
benefit of the yield() call under congestion.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch moves the preliminary checkings that must be fulfilled
to update a conntrack, which are the following:
* NAT manglings cannot be updated
* Changing the master conntrack is not allowed.
This patch is a cleanup.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch moves the assignation of the master conntrack to
ctnetlink_create_conntrack(), which is where it really belongs.
This patch is a cleanup.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch modifies the proc output to add display of registered
loggers. The content of /proc/net/netfilter/nf_log is modified. Instead
of displaying a protocol per line with format:
proto:logger
it now displays:
proto:logger (comma_separated_list_of_loggers)
NONE is used as keyword if no logger is used.
Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch modifies nf_log to use a linked list of loggers for each
protocol. This list of loggers is read and write protected with a
mutex.
This patch separates registration and binding. To be used as
logging module, a module has to register calling nf_log_register()
and to bind to a protocol it has to call nf_log_bind_pf().
This patch also converts the logging modules to the new API. For nfnetlink_log,
it simply switchs call to register functions to call to bind function and
adds a call to nf_log_register() during init. For other modules, it just
remove a const flag from the logger structure and replace it with a
__read_mostly.
Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Commit 784544739a
(netfilter: iptables: lock free counters) broke xt_hashlimit netfilter module :
This module was storing a pointer inside its xt_hashlimit_info, and this pointer
is not relocated when we temporarly switch tables (iptables -L).
This hack is not not needed at all (probably a leftover from
ancient time), as each cpu should and can access to its own copy.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Fix regression introduded by commit 079aa88 (netfilter: xt_recent: IPv6 support):
From http://bugzilla.kernel.org/show_bug.cgi?id=12753:
Problem Description:
An uninitialized buffer causes IPv4 addresses added manually (via the +IP
command to the proc interface) to never match any packets. Similarly, the -IP
command fails to remove IPv4 addresses.
Details:
In the function recent_entry_lookup, the xt_recent module does comparisons of
the entire nf_inet_addr union value, both for IPv4 and IPv6 addresses. For
addresses initialized from actual packets the remaining 12 bytes not occupied
by the IPv4 are zeroed so this works correctly. However when setting the
nf_inet_addr addr variable in the recent_mt_proc_write function, only the IPv4
bytes are initialized and the remaining 12 bytes contain garbage.
Hence addresses added in this way never match any packets, unless these
uninitialized 12 bytes happened to be zero by coincidence. Similarly, addresses
cannot consistently be removed using the proc interface due to mismatch of the
garbage bytes (although it will sometimes work to remove an address that was
added manually).
Reading the /proc/net/xt_recent/ entries hides this problem because this only
uses the first 4 bytes when displaying IPv4 addresses.
Steps to reproduce:
$ iptables -I INPUT -m recent --rcheck -j LOG
$ echo +169.254.156.239 > /proc/net/xt_recent/DEFAULT
$ cat /proc/net/xt_recent/DEFAULT
src=169.254.156.239 ttl: 0 last_seen: 119910 oldest_pkt: 1 119910
[At this point no packets from 169.254.156.239 are being logged.]
$ iptables -I INPUT -s 169.254.156.239 -m recent --set
$ cat /proc/net/xt_recent/DEFAULT
src=169.254.156.239 ttl: 0 last_seen: 119910 oldest_pkt: 1 119910
src=169.254.156.239 ttl: 255 last_seen: 126184 oldest_pkt: 4 125434, 125684, 125934, 126184
[At this point, adding the address via an iptables rule, packets are being
logged correctly.]
$ echo -169.254.156.239 > /proc/net/xt_recent/DEFAULT
$ cat /proc/net/xt_recent/DEFAULT
src=169.254.156.239 ttl: 0 last_seen: 119910 oldest_pkt: 1 119910
src=169.254.156.239 ttl: 255 last_seen: 126992 oldest_pkt: 10 125434, 125684, 125934, 126184, 126434, 126684, 126934, 126991, 126991, 126992
$ echo -169.254.156.239 > /proc/net/xt_recent/DEFAULT
$ cat /proc/net/xt_recent/DEFAULT
src=169.254.156.239 ttl: 0 last_seen: 119910 oldest_pkt: 1 119910
src=169.254.156.239 ttl: 255 last_seen: 126992 oldest_pkt: 10 125434, 125684, 125934, 126184, 126434, 126684, 126934, 126991, 126991, 126992
[Removing the address via /proc interface failed evidently.]
Possible solutions:
- initialize the addr variable in recent_mt_proc_write
- compare only 4 bytes for IPv4 addresses in recent_entry_lookup
Signed-off-by: Patrick McHardy <kaber@trash.net>
Since tcp_packet() may return -NF_DROP in two situations, the
packet-drop stats must be increased.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Kernel module providing implementation of LED netfilter target. Each
instance of the target appears as a led-trigger device, which can be
associated with one or more LEDs in /sys/class/leds/
Signed-off-by: Adam Nielsen <a.nielsen@shikadi.net>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
get_random_bytes() is sometimes called with a hard coded size assumption
of an integer. This could not be true for next centuries. This patch
replace it with a compile time statement.
Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Table size is defined as unsigned, wheres the table maximum size is
defined as a signed integer. The calculation of max is 8 or 4,
multiplied the table size. Therefore the max value is aligned to
unsigned.
Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
Signed-off-by: Patrick McHardy <kaber@trash.net>
The reader/writer lock in ip_tables is acquired in the critical path of
processing packets and is one of the reasons just loading iptables can cause
a 20% performance loss. The rwlock serves two functions:
1) it prevents changes to table state (xt_replace) while table is in use.
This is now handled by doing rcu on the xt_table. When table is
replaced, the new table(s) are put in and the old one table(s) are freed
after RCU period.
2) it provides synchronization when accesing the counter values.
This is now handled by swapping in new table_info entries for each cpu
then summing the old values, and putting the result back onto one
cpu. On a busy system it may cause sampling to occur at different
times on each cpu, but no packet/byte counts are lost in the process.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Sucessfully tested on my dual quad core machine too, but iptables only (no ipv6 here)
BTW, my new "tbench 8" result is 2450 MB/s, (it was 2150 MB/s not so long ago)
Acked-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
xt_physdev netfilter module can use an ifname_compare() helper
so that two loops are unfolded.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
1) physdev_mt() incorrectly assumes nulldevname[] is aligned on an int
2) It also uses word comparisons, while it could use long word ones.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Suggested by: James King <t.james.king@gmail.com>
Similarly to commit c9fd496809, merge
TTL and HL. Since HL does not depend on any IPv6-specific function,
no new module dependencies would arise.
With slight adjustments to the Kconfig help text.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
When extensions were moved to the NFPROTO_UNSPEC wildcard in
ab4f21e6fb, they disappeared from the
procfs files.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
0 is used by Hop-by-hop header and so this may cause confusion.
255 is stated as 'Reserved' by IANA.
Signed-off-by: Christoph Paasch <christoph.paasch@student.uclouvain.be>
Signed-off-by: Patrick McHardy <kaber@trash.net>
NFLOG timeout was computed in timer by doing:
flushtimeout*HZ/100
Default value of flushtimeout was HZ (for 1 second delay). This was
wrong for non 100HZ computer. This patch modify the default delay by
using 100 instead of HZ.
Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
