Connection tracking helpers have to drop packets under exceptional
situations. Currently, the user gets the following logging message
in case that happens:
nf_ct_%s: dropping packet ...
However, depending on the helper, there are different reasons why a
packet can be dropped.
This patch modifies the existing code to provide more specific
error message in the scope of each helper to help users to debug
the reason why the packet has been dropped, ie:
nf_ct_%s: dropping packet: reason ...
Thanks to Joe Perches for many formatting suggestions.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
This batch contains netfilter updates for you net-next tree, they are:
* The new connlabel extension for x_tables, that allows us to attach
labels to each conntrack flow. The kernel implementation uses a
bitmask and there's a file in user-space that maps the bits with the
corresponding string for each existing label. By now, you can attach
up to 128 overlapping labels. From Florian Westphal.
* A new round of improvements for the netns support for conntrack.
Gao feng has moved many of the initialization code of each module
of the netns init path. He also made several code refactoring, that
code looks cleaner to me now.
* Added documentation for all possible tweaks for nf_conntrack via
sysctl, from Jiri Pirko.
* Cisco 7941/7945 IP phone support for our SIP conntrack helper,
from Kevin Cernekee.
* Missing header file in the snmp helper, from Stephen Hemminger.
* Finally, a couple of fixes to resolve minor issues with these
changes, from myself.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Motivation for soreuseport would be something like a web server
binding to port 80 running with multiple threads, where each thread
might have it's own listener socket. This could be done as an
alternative to other models: 1) have one listener thread which
dispatches completed connections to workers. 2) accept on a single
listener socket from multiple threads. In case #1 the listener thread
can easily become the bottleneck with high connection turn-over rate.
In case #2, the proportion of connections accepted per thread tends
to be uneven under high connection load (assuming simple event loop:
while (1) { accept(); process() }, wakeup does not promote fairness
among the sockets. We have seen the disproportion to be as high
as 3:1 ratio between thread accepting most connections and the one
accepting the fewest. With so_reusport the distribution is
uniform.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow multiple listener sockets to bind to the same port.
Motivation for soresuseport would be something like a web server
binding to port 80 running with multiple threads, where each thread
might have it's own listener socket. This could be done as an
alternative to other models: 1) have one listener thread which
dispatches completed connections to workers. 2) accept on a single
listener socket from multiple threads. In case #1 the listener thread
can easily become the bottleneck with high connection turn-over rate.
In case #2, the proportion of connections accepted per thread tends
to be uneven under high connection load (assuming simple event loop:
while (1) { accept(); process() }, wakeup does not promote fairness
among the sockets. We have seen the disproportion to be as high
as 3:1 ratio between thread accepting most connections and the one
accepting the fewest. With so_reusport the distribution is
uniform.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the code that register/unregister l4proto to the
module_init/exit context.
Given that we have to modify some interfaces to accomodate
these changes, it is a good time to use shorter function names
for this using the nf_ct_* prefix instead of nf_conntrack_*,
that is:
nf_ct_l4proto_register
nf_ct_l4proto_pernet_register
nf_ct_l4proto_unregister
nf_ct_l4proto_pernet_unregister
We same many line breaks with it.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move the code that register/unregister l3proto to the
module_init/exit context.
Given that we have to modify some interfaces to accomodate
these changes, it is a good time to use shorter function names
for this using the nf_ct_* prefix instead of nf_conntrack_*,
that is:
nf_ct_l3proto_register
nf_ct_l3proto_pernet_register
nf_ct_l3proto_unregister
nf_ct_l3proto_pernet_unregister
We same many line breaks with it.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move the global initial codes to the module_init/exit context.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move the global initial codes to the module_init/exit context.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move the global initial codes to the module_init/exit context.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move the global initial codes to the module_init/exit context.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move the global initial codes to the module_init/exit context.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move the global initial codes to the module_init/exit context.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move the global initial codes to the module_init/exit context.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move the global initial codes to the module_init/exit context.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_conntrack initialization and cleanup codes happens in pernet
operations function. This task should be done in module_init/exit.
We can't use init_net to identify if it's the right time to initialize
or cleanup since we cannot make assumption on the order netns are
created/destroyed.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add the ability to set/clear labels assigned to a conntrack
via ctnetlink.
To allow userspace to only alter specific bits, Pablo suggested to add
a new CTA_LABELS_MASK attribute:
The new set of active labels is then determined via
active = (active & ~mask) ^ changeset
i.e., the mask selects those bits in the existing set that should be
changed.
This follows the same method already used by MARK and CONNMARK targets.
Omitting CTA_LABELS_MASK is the same as setting all bits in CTA_LABELS_MASK
to 1: The existing set is replaced by the one from userspace.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
similar to connmarks, except labels are bit-based; i.e.
all labels may be attached to a flow at the same time.
Up to 128 labels are supported. Supporting more labels
is possible, but requires increasing the ct offset delta
from u8 to u16 type due to increased extension sizes.
Mapping of bit-identifier to label name is done in userspace.
The extension is enabled at run-time once "-m connlabel" netfilter
rules are added.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
canqun zhang reported that we're hitting BUG_ON in the
nf_conntrack_destroy path when calling kfree_skb while
rmmod'ing the nf_conntrack module.
Currently, the nf_ct_destroy hook is being set to NULL in the
destroy path of conntrack.init_net. However, this is a problem
since init_net may be destroyed before any other existing netns
(we cannot assume any specific ordering while releasing existing
netns according to what I read in recent emails).
Thanks to Gao feng for initial patch to address this issue.
Reported-by: canqun zhang <canqunzhang@gmail.com>
Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When the route changes (backup default route, VPNs) which affect a
masqueraded target, the packets were sent out with the outdated source
address. The patch addresses the issue by comparing the outgoing interface
directly with the masqueraded interface in the nat table.
Events are inefficient in this case, because it'd require adding route
events to the network core and then scanning the whole conntrack table
and re-checking the route for all entry.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We used to have several queueing backends, but nowadays only
nfnetlink_queue remains.
In light of this there doesn't seem to be a good reason to
support per-af registering -- just hook up nfnetlink_queue on module
load and remove it on unload.
This means that the userspace BIND/UNBIND_PF commands are now obsolete;
the kernel will ignore them.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch modifies the conntrack subsystem so that all existing
allocated conntrack objects can be found in any of the following
places:
* the hash table, this is the typical place for alive conntrack objects.
* the unconfirmed list, this is the place for newly created conntrack objects
that are still traversing the stack.
* the dying list, this is where you can find conntrack objects that are dying
or that should die anytime soon (eg. once the destroy event is delivered to
the conntrackd daemon).
Thus, we make sure that we follow the track for all existing conntrack
objects. This patch, together with some extension of the ctnetlink interface
to dump the content of the dying and unconfirmed lists, will help in case
to debug suspected nf_conn object leaks.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
This patch adds the new nf_ct_timeout_lookup function to encapsulate
the timeout policy attachment that is called in the nf_conntrack_in
path.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Existing code assumes that del_timer returns true for alive conntrack
entries. However, this is not true if reliable events are enabled.
In that case, del_timer may return true for entries that were
just inserted in the dying list. Note that packets / ctnetlink may
hold references to conntrack entries that were just inserted to such
list.
This patch fixes the issue by adding an independent timer for
event delivery. This increases the size of the ecache extension.
Still we can revisit this later and use variable size extensions
to allocate this area on demand.
Tested-by: Oliver Smith <olipro@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
