Commit Graph

407 Commits

Author SHA1 Message Date
Krishna Kumar
46ba5a25f5 netfilter: nfnetlink_queue: do not allow to set unsupported flag bits
Allow setting of only supported flag bits in queue->flags.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-07-04 19:51:50 +02:00
Pablo Neira Ayuso
392025f87a netfilter: ctnetlink: add new messages to obtain statistics
This patch adds the following messages to ctnetlink:

IPCTNL_MSG_CT_GET_STATS_CPU
IPCTNL_MSG_CT_GET_STATS
IPCTNL_MSG_EXP_GET_STATS_CPU

To display connection tracking system per-cpu and global statistics.

This provides a replacement for the following /proc interfaces:

/proc/net/stat/nf_conntrack
/proc/sys/net/netfilter/nf_conntrack_count

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 17:28:03 +02:00
David S. Miller
82f437b950 Merge branch 'master' of git://1984.lsi.us.es/nf-next
Pablo says:

====================
This is the second batch of Netfilter updates for net-next. It contains the
kernel changes for the new user-space connection tracking helper
infrastructure.

More details on this infrastructure are provides here:
http://lwn.net/Articles/500196/

Still, I plan to provide some official documentation through the
conntrack-tools user manual on how to setup user-space utilities for this.
So far, it provides two helper in user-space, one for NFSv3 and another for
Oracle/SQLnet/TNS. Yet in my TODO list.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-16 15:23:35 -07:00
Pablo Neira Ayuso
12f7a50533 netfilter: add user-space connection tracking helper infrastructure
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 <pablo@netfilter.org>
2012-06-16 15:40:02 +02:00
Pablo Neira Ayuso
ae243bee39 netfilter: ctnetlink: add CTA_HELP_INFO attribute
This attribute can be used to modify and to dump the internal
protocol information.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-16 15:09:15 +02:00
Pablo Neira Ayuso
9cb0176654 netfilter: add glue code to integrate nfnetlink_queue and ctnetlink
This patch allows you to include the conntrack information together
with the packet that is sent to user-space via NFQUEUE.

Previously, there was no integration between ctnetlink and
nfnetlink_queue. If you wanted to access conntrack information
from your libnetfilter_queue program, you required to query
ctnetlink from user-space to obtain it. Thus, delaying the packet
processing even more.

Including the conntrack information is optional, you can set it
via NFQA_CFG_F_CONNTRACK flag with the new NFQA_CFG_FLAGS attribute.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-16 15:09:02 +02:00
Pablo Neira Ayuso
1afc56794e netfilter: nf_ct_helper: implement variable length helper private data
This patch uses the new variable length conntrack extensions.

Instead of using union nf_conntrack_help that contain all the
helper private data information, we allocate variable length
area to store the private helper data.

This patch includes the modification of all existing helpers.
It also includes a couple of include header to avoid compilation
warnings.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-16 15:08:55 +02:00
David S. Miller
43b03f1f6d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	MAINTAINERS
	drivers/net/wireless/iwlwifi/pcie/trans.c

The iwlwifi conflict was resolved by keeping the code added
in 'net' that turns off the buggy chip feature.

The MAINTAINERS conflict was merely overlapping changes, one
change updated all the wireless web site URLs and the other
changed some GIT trees to be Johannes's instead of John's.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-12 21:59:18 -07:00
Denys Fedoryshchenko
efdedd5426 netfilter: xt_recent: add address masking option
The mask option allows you put all address belonging that mask into
the same recent slot. This can be useful in case that recent is used
to detect attacks from the same network segment.

Tested for backward compatibility.

Signed-off-by: Denys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-07 14:58:42 +02:00
Krishna Kumar
fdb694a01f netfilter: Add fail-open support
Implement a new "fail-open" mode where packets are not dropped
upon queue-full condition. This mode can be enabled/disabled per
queue using netlink NFQA_CFG_FLAGS & NFQA_CFG_MASK attributes.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: Vivek Kashyap <vivk@us.ibm.com>
Signed-off-by: Sridhar Samudrala <samudrala@us.ibm.com>
2012-06-07 14:58:39 +02:00
Cong Wang
68c07cb6d8 netfilter: xt_connlimit: remove revision 0
It was scheduled to be removed.

Cc: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-07 14:58:39 +02:00
Hans Schillstrom
d1992b169d netfilter: xt_HMARK: fix endianness and provide consistent hashing
This patch addresses two issues:

a) Fix usage of u32 and __be32 that causes endianess warnings via sparse.
b) Ensure consistent hashing in a cluster that is composed of big and
   little endian systems. Thus, we obtain the same hash mark in an
   heterogeneous cluster.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-07 14:53:01 +02:00
David S. Miller
028940342a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-16 22:17:37 -04:00
Jozsef Kadlecsik
127f559127 netfilter: ipset: fix timeout value overflow bug
Large timeout parameters could result wrong timeout values due to
an overflow at msec to jiffies conversion (reported by Andreas Herz)

[ This patch was mangled by Pablo Neira Ayuso since David Laight and
  Eric Dumazet noticed that we were using hardcoded 1000 instead of
  MSEC_PER_SEC to calculate the timeout ]

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-05-17 00:56:41 +02:00
Florian Westphal
1f27e2516c netfilter: xt_hashlimit: use _ALL macro to reject unknown flag bits
David Miller says:
     The canonical way to validate if the set bits are in a valid
     range is to have a "_ALL" macro, and test:
     if (val & ~XT_HASHLIMIT_ALL)
         goto err;"

make it so.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-05-17 00:56:31 +02:00
Jozsef Kadlecsik
26a5d3cc0b netfilter: ipset: fix hash size checking in kernel
The hash size must fit both into u32 (jhash) and the max value of
size_t. The missing checking could lead to kernel crash, bug reported
by Seblu.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-16 15:38:49 -04:00
Florian Westphal
0197dee7d3 netfilter: hashlimit: byte-based limit mode
can be used e.g. for ingress traffic policing or
to detect when a host/port consumes more bandwidth than expected.

This is done by optionally making cost to mean
"cost per 16-byte-chunk-of-data" instead of "cost per packet".

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-05-09 13:04:57 +02:00
Hans Schillstrom
cf308a1fae netfilter: add xt_hmark target for hash-based skb marking
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 <hans.schillstrom@ericsson.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-05-09 12:54:05 +02:00
Pablo Neira Ayuso
6714cf5465 netfilter: nf_conntrack: fix explicit helper attachment and NAT
Explicit helper attachment via the CT target is broken with NAT
if non-standard ports are used. This problem was hidden behind
the automatic helper assignment routine. Thus, it becomes more
noticeable now that we can disable the automatic helper assignment
with Eric Leblond's:

9e8ac5a netfilter: nf_ct_helper: allow to disable automatic helper assignment

Basically, nf_conntrack_alter_reply asks for looking up the helper
up if NAT is enabled. Unfortunately, we don't have the conntrack
template at that point anymore.

Since we don't want to rely on the automatic helper assignment,
we can skip the second look-up and stick to the helper that was
attached by iptables. With the CT target, the user is in full
control of helper attachment, thus, the policy is to trust what
the user explicitly configures via iptables (no automatic magic
anymore).

Interestingly, this bug was hidden by the automatic helper look-up
code. But it can be easily trigger if you attach the helper in
a non-standard port, eg.

iptables -I PREROUTING -t raw -p tcp --dport 8888 \
	-j CT --helper ftp

And you disabled the automatic helper assignment.

I added the IPS_HELPER_BIT that allows us to differenciate between
a helper that has been explicitly attached and those that have been
automatically assigned. I didn't come up with a better solution
(having backward compatibility in mind).

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-05-08 19:44:42 +02:00
Eric Dumazet
95c9617472 net: cleanup unsigned to unsigned int
Use of "unsigned int" is preferred to bare "unsigned" in net tree.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15 12:44:40 -04:00
David S. Miller
06eb4eafbd Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-04-10 14:30:45 -04:00
David S. Miller
7cf7899d9e ipset: Stop using NLA_PUT*().
These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-02 04:33:41 -04:00
Jan Engelhardt
5276e16bb6 netfilter: ipset: avoid use of kernel-only types
When using the xt_set.h header in userspace, one will get these gcc
reports:

ipset/ip_set.h:184:1: error: unknown type name "u16"
In file included from libxt_SET.c:21:0:
netfilter/xt_set.h:61:2: error: unknown type name "u32"
netfilter/xt_set.h:62:2: error: unknown type name "u32"

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-03-26 21:06:30 +02:00
Pablo Neira Ayuso
24de58f465 netfilter: xt_CT: allow to attach timeout policy + glue code
This patch allows you to attach the timeout policy via the
CT target, it adds a new revision of the target to ensure
backward compatibility. Moreover, it also contains the glue
code to stick the timeout object defined via nfnetlink_cttimeout
to the given flow.

Example usage (it requires installing the nfct tool and
libnetfilter_cttimeout):

1) create the timeout policy:

 nfct timeout add tcp-policy0 inet tcp \
	established 1000 close 10 time_wait 10 last_ack 10

2) attach the timeout policy to the packet:

 iptables -I PREROUTING -t raw -p tcp -j CT --timeout tcp-policy0

You have to install the following user-space software:

a) libnetfilter_cttimeout:
   git://git.netfilter.org/libnetfilter_cttimeout

b) nfct:
   git://git.netfilter.org/nfct

You also have to get iptables with -j CT --timeout support.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-03-07 17:41:28 +01:00
Pablo Neira Ayuso
5097846230 netfilter: add cttimeout infrastructure for fine timeout tuning
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 <pablo@netfilter.org>
2012-03-07 17:41:22 +01:00