linux-stable.git/net/netfilter/Makefile, branch linux-3.6.y

netfilter: nfnetlink_queue: fix compilation with NF_CONNTRACK disabled

2012-06-19T02:44:57+00:00

In "9cb0176 netfilter: add glue code to integrate nfnetlink_queue and ctnetlink"
the compilation with NF_CONNTRACK disabled is broken. This patch fixes this
issue.

I have moved the conntrack part into nfnetlink_queue_ct.c to avoid
peppering the entire nfnetlink_queue.c code with ifdefs.

I also needed to rename nfnetlink_queue.c to nfnetlink_queue_pkt.c
to update the net/netfilter/Makefile to support conditional compilation
of the conntrack integration.

This patch also adds CONFIG_NETFILTER_QUEUE_CT in case you want to explicitly
disable the integration between nf_conntrack and nfnetlink_queue.

Reported-by: Andrew Morton 
Signed-off-by: Pablo Neira Ayuso

netfilter: fix compilation of the nfnl_cthelper if NF_CONNTRACK is unset

2012-06-18T23:25:08+00:00

This patch fixes the compilation of net/netfilter/nfnetlink_cthelper.c
if CONFIG_NF_CONNTRACK is not set.

This patch also moves the definition of the cthelper infrastructure to
the scope of NF_CONNTRACK things.

I have also renamed NETFILTER_NETLINK_CTHELPER by NF_CT_NETLINK_HELPER,
to use similar names to other nf_conntrack_netlink extensions. Better now
that this has been only for two days in David's tree.

Two new dependencies have been added:

* NF_CT_NETLINK
* NETFILTER_NETLINK_QUEUE

Since these infrastructure requires both ctnetlink and nfqueue.

Reported-by: Randy Dunlap 
Signed-off-by: Pablo Neira Ayuso

netfilter: add user-space connection tracking helper infrastructure

2012-06-16T13:40:02+00:00

There are good reasons to supports helpers in user-space instead:

* Rapid connection tracking helper development, as developing code
  in user-space is usually faster.

* Reliability: A buggy helper does not crash the kernel. Moreover,
  we can monitor the helper process and restart it in case of problems.

* Security: Avoid complex string matching and mangling in kernel-space
  running in privileged mode. Going further, we can even think about
  running user-space helpers as a non-root process.

* Extensibility: It allows the development of very specific helpers (most
  likely non-standard proprietary protocols) that are very likely not to be
  accepted for mainline inclusion in the form of kernel-space connection
  tracking helpers.

This patch adds the infrastructure to allow the implementation of
user-space conntrack helpers by means of the new nfnetlink subsystem
`nfnetlink_cthelper' and the existing queueing infrastructure
(nfnetlink_queue).

I had to add the new hook NF_IP6_PRI_CONNTRACK_HELPER to register
ipv[4|6]_helper which results from splitting ipv[4|6]_confirm into
two pieces. This change is required not to break NAT sequence
adjustment and conntrack confirmation for traffic that is enqueued
to our user-space conntrack helpers.

Basic operation, in a few steps:

1) Register user-space helper by means of `nfct':

 nfct helper add ftp inet tcp

 [ It must be a valid existing helper supported by conntrack-tools ]

2) Add rules to enable the FTP user-space helper which is
   used to track traffic going to TCP port 21.

For locally generated packets:

 iptables -I OUTPUT -t raw -p tcp --dport 21 -j CT --helper ftp

For non-locally generated packets:

 iptables -I PREROUTING -t raw -p tcp --dport 21 -j CT --helper ftp

3) Run the test conntrackd in helper mode (see example files under
   doc/helper/conntrackd.conf

 conntrackd

4) Generate FTP traffic going, if everything is OK, then conntrackd
   should create expectations (you can check that with `conntrack':

 conntrack -E expect

    [NEW] 301 proto=6 src=192.168.1.136 dst=130.89.148.12 sport=0 dport=54037 mask-src=255.255.255.255 mask-dst=255.255.255.255 sport=0 dport=65535 master-src=192.168.1.136 master-dst=130.89.148.12 sport=57127 dport=21 class=0 helper=ftp
[DESTROY] 301 proto=6 src=192.168.1.136 dst=130.89.148.12 sport=0 dport=54037 mask-src=255.255.255.255 mask-dst=255.255.255.255 sport=0 dport=65535 master-src=192.168.1.136 master-dst=130.89.148.12 sport=57127 dport=21 class=0 helper=ftp

This confirms that our test helper is receiving packets including the
conntrack information, and adding expectations in kernel-space.

The user-space helper can also store its private tracking information
in the conntrack structure in the kernel via the CTA_HELP_INFO. The
kernel will consider this a binary blob whose layout is unknown. This
information will be included in the information that is transfered
to user-space via glue code that integrates nfnetlink_queue and
ctnetlink.

Signed-off-by: Pablo Neira Ayuso

netfilter: add xt_hmark target for hash-based skb marking

2012-05-09T10:54:05+00:00

The target allows you to create rules in the "raw" and "mangle" tables
which set the skbuff mark by means of hash calculation within a given
range. The nfmark can influence the routing method (see "Use netfilter
MARK value as routing key") and can also be used by other subsystems to
change their behaviour.

[ Part of this patch has been refactorized and modified by Pablo Neira Ayuso ]

Signed-off-by: Hans Schillstrom 
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_ct_ext: add timeout extension

2012-03-07T16:41:25+00:00

This patch adds the timeout extension, which allows you to attach
specific timeout policies to flows.

This extension is only used by the template conntrack.

Signed-off-by: Pablo Neira Ayuso

netfilter: add cttimeout infrastructure for fine timeout tuning

2012-03-07T16:41:22+00:00

This patch adds the infrastructure to add fine timeout tuning
over nfnetlink. Now you can use the NFNL_SUBSYS_CTNETLINK_TIMEOUT
subsystem to create/delete/dump timeout objects that contain some
specific timeout policy for one flow.

The follow up patches will allow you attach timeout policy object
to conntrack via the CT target and the conntrack extension
infrastructure.

Signed-off-by: Pablo Neira Ayuso

netfilter: merge ipt_LOG and ip6_LOG into xt_LOG

2012-03-07T16:40:49+00:00

ipt_LOG and ip6_LOG have a lot of common code, merge them
to reduce duplicate code.

Signed-off-by: Richard Weinberger 
Signed-off-by: Pablo Neira Ayuso

netfilter: xtables: move ipt_ecn to xt_ecn

2011-12-27T19:31:31+00:00

Prepare the ECN match for augmentation by an IPv6 counterpart. Since
no symbol dependencies to ipv6.ko are added, having a single ecn match
module is the more so welcome.

Signed-off-by: Jan Engelhardt 
Signed-off-by: Pablo Neira Ayuso

netfilter: xtables: add nfacct match to support extended accounting

2011-12-25T01:43:17+00:00

This patch adds the match that allows to perform extended
accounting. It requires the new nfnetlink_acct infrastructure.

 # iptables -I INPUT -p tcp --sport 80 -m nfacct --nfacct-name http-traffic
 # iptables -I OUTPUT -p tcp --dport 80 -m nfacct --nfacct-name http-traffic

Signed-off-by: Pablo Neira Ayuso

netfilter: add extended accounting infrastructure over nfnetlink

2011-12-25T01:43:03+00:00

We currently have two ways to account traffic in netfilter:

- iptables chain and rule counters:

 # iptables -L -n -v
Chain INPUT (policy DROP 3 packets, 867 bytes)
 pkts bytes target     prot opt in     out     source               destination
    8  1104 ACCEPT     all  --  lo     *       0.0.0.0/0            0.0.0.0/0

- use flow-based accounting provided by ctnetlink:

 # conntrack -L
tcp      6 431999 ESTABLISHED src=192.168.1.130 dst=212.106.219.168 sport=58152 dport=80 packets=47 bytes=7654 src=212.106.219.168 dst=192.168.1.130 sport=80 dport=58152 packets=49 bytes=66340 [ASSURED] mark=0 use=1

While trying to display real-time accounting statistics, we require
to pool the kernel periodically to obtain this information. This is
OK if the number of flows is relatively low. However, in case that
the number of flows is huge, we can spend a considerable amount of
cycles to iterate over the list of flows that have been obtained.

Moreover, if we want to obtain the sum of the flow accounting results
that match some criteria, we have to iterate over the whole list of
existing flows, look for matchings and update the counters.

This patch adds the extended accounting infrastructure for
nfnetlink which aims to allow displaying real-time traffic accounting
without the need of complicated and resource-consuming implementation
in user-space. Basically, this new infrastructure allows you to create
accounting objects. One accounting object is composed of packet and
byte counters.

In order to manipulate create accounting objects, you require the
new libnetfilter_acct library. It contains several examples of use:

libnetfilter_acct/examples# ./nfacct-add http-traffic
libnetfilter_acct/examples# ./nfacct-get
http-traffic = { pkts = 000000000000,   bytes = 000000000000 };

Then, you can use one of this accounting objects in several iptables
rules using the new nfacct match (which comes in a follow-up patch):

 # iptables -I INPUT -p tcp --sport 80 -m nfacct --nfacct-name http-traffic
 # iptables -I OUTPUT -p tcp --dport 80 -m nfacct --nfacct-name http-traffic

The idea is simple: if one packet matches the rule, the nfacct match
updates the counters.

Thanks to Patrick McHardy, Eric Dumazet, Changli Gao for reviewing and
providing feedback for this contribution.

Signed-off-by: Pablo Neira Ayuso