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1932 Commits (76ac66e469f084d41742ba08923de76fbdc7dce3)

Author SHA1 Message Date
David S. Miller 6c71bec66a Merge git://1984.lsi.us.es/nf
Pable Neira Ayuso says:

====================
The following five patches contain fixes for 3.6-rc, they are:

* Two fixes for message parsing in the SIP conntrack helper, from
  Patrick McHardy.

* One fix for the SIP helper introduced in the user-space cthelper
  infrastructure, from Patrick McHardy.

* fix missing appropriate locking while modifying one conntrack entry
  from the nfqueue integration code, from myself.

* fix possible access to uninitiliazed timer in the nf_conntrack
  expectation infrastructure, from myself.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-20 02:44:29 -07:00
Pablo Neira Ayuso 2614f86490 netfilter: nf_ct_expect: fix possible access to uninitialized timer
In __nf_ct_expect_check, the function refresh_timer returns 1
if a matching expectation is found and its timer is successfully
refreshed. This results in nf_ct_expect_related returning 0.
Note that at this point:

- the passed expectation is not inserted in the expectation table
  and its timer was not initialized, since we have refreshed one
  matching/existing expectation.

- nf_ct_expect_alloc uses kmem_cache_alloc, so the expectation
  timer is in some undefined state just after the allocation,
  until it is appropriately initialized.

This can be a problem for the SIP helper during the expectation
addition:

 ...
 if (nf_ct_expect_related(rtp_exp) == 0) {
         if (nf_ct_expect_related(rtcp_exp) != 0)
                 nf_ct_unexpect_related(rtp_exp);
 ...

Note that nf_ct_expect_related(rtp_exp) may return 0 for the timer refresh
case that is detailed above. Then, if nf_ct_unexpect_related(rtcp_exp)
returns != 0, nf_ct_unexpect_related(rtp_exp) is called, which does:

 spin_lock_bh(&nf_conntrack_lock);
 if (del_timer(&exp->timeout)) {
         nf_ct_unlink_expect(exp);
         nf_ct_expect_put(exp);
 }
 spin_unlock_bh(&nf_conntrack_lock);

Note that del_timer always returns false if the timer has been
initialized.  However, the timer was not initialized since setup_timer
was not called, therefore, the expectation timer remains in some
undefined state. If I'm not missing anything, this may lead to the
removal an unexistent expectation.

To fix this, the optimization that allows refreshing an expectation
is removed. Now nf_conntrack_expect_related looks more consistent
to me since it always add the expectation in case that it returns
success.

Thanks to Patrick McHardy for participating in the discussion of
this patch.

I think this may be the source of the problem described by:
http://marc.info/?l=netfilter-devel&m=134073514719421&w=2

Reported-by: Rafal Fitt <rafalf@aplusc.com.pl>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-08-16 11:49:53 +02:00
Mathias Krause 2d8a041b7b ipvs: fix info leak in getsockopt(IP_VS_SO_GET_TIMEOUT)
If at least one of CONFIG_IP_VS_PROTO_TCP or CONFIG_IP_VS_PROTO_UDP is
not set, __ip_vs_get_timeouts() does not fully initialize the structure
that gets copied to userland and that for leaks up to 12 bytes of kernel
stack. Add an explicit memset(0) before passing the structure to
__ip_vs_get_timeouts() to avoid the info leak.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Wensong Zhang <wensong@linux-vs.org>
Cc: Simon Horman <horms@verge.net.au>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-15 21:36:31 -07:00
Pablo Neira Ayuso 68e035c950 netfilter: ctnetlink: fix missing locking while changing conntrack from nfqueue
Since 9cb017665 netfilter: add glue code to integrate nfnetlink_queue and
ctnetlink, we can modify the conntrack entry via nfnl_queue. However, the
change of the conntrack entry via nfnetlink_queue requires appropriate
locking to avoid concurrent updates.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-08-14 12:54:45 +02:00
Patrick McHardy 02b69cbdc2 netfilter: nf_ct_sip: fix IPv6 address parsing
Within SIP messages IPv6 addresses are enclosed in square brackets in most
cases, with the exception of the "received=" header parameter. Currently
the helper fails to parse enclosed addresses.

This patch:

- changes the SIP address parsing function to enforce square brackets
  when required, and accept them when not required but present, as
  recommended by RFC 5118.

- adds a new SDP address parsing function that never accepts square
  brackets since SDP doesn't use them.

With these changes, the SIP helper correctly parses all test messages
from RFC 5118 (Session Initiation Protocol (SIP) Torture Test Messages
for Internet Protocol Version 6 (IPv6)).

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-08-10 11:53:11 +02:00
Patrick McHardy e9324b2ce6 netfilter: nf_ct_sip: fix helper name
Commit 3a8fc53a (netfilter: nf_ct_helper: allocate 16 bytes for the helper
and policy names) introduced a bug in the SIP helper, the helper name is
sprinted to the sip_names array instead of instead of into the helper
structure. This breaks the helper match and the /proc/net/nf_conntrack_expect
output.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-08-10 11:53:03 +02:00
David S. Miller abaa72d7fd Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
2012-07-19 11:17:30 -07:00
David S. Miller 6700c2709c net: Pass optional SKB and SK arguments to dst_ops->{update_pmtu,redirect}()
This will be used so that we can compose a full flow key.

Even though we have a route in this context, we need more.  In the
future the routes will be without destination address, source address,
etc. keying.  One ipv4 route will cover entire subnets, etc.

In this environment we have to have a way to possess persistent storage
for redirects and PMTU information.  This persistent storage will exist
in the FIB tables, and that's why we'll need to be able to rebuild a
full lookup flow key here.  Using that flow key will do a fib_lookup()
and create/update the persistent entry.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-17 03:29:28 -07:00
Julian Anastasov 283283c4da ipvs: fix oops in ip_vs_dst_event on rmmod
After commit 39f618b4fd (3.4)
"ipvs: reset ipvs pointer in netns" we can oops in
ip_vs_dst_event on rmmod ip_vs because ip_vs_control_cleanup
is called after the ipvs_core_ops subsys is unregistered and
net->ipvs is NULL. Fix it by exiting early from ip_vs_dst_event
if ipvs is NULL. It is safe because all services and dests
for the net are already freed.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-07-17 12:00:58 +02:00
David S. Miller 04c9f416e3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/batman-adv/bridge_loop_avoidance.c
	net/batman-adv/bridge_loop_avoidance.h
	net/batman-adv/soft-interface.c
	net/mac80211/mlme.c

With merge help from Antonio Quartulli (batman-adv) and
Stephen Rothwell (drivers/net/usb/qmi_wwan.c).

The net/mac80211/mlme.c conflict seemed easy enough, accounting for a
conversion to some new tracing macros.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-10 23:56:33 -07:00
Ben Hutchings 2c53040f01 net: Fix (nearly-)kernel-doc comments for various functions
Fix incorrect start markers, wrapped summary lines, missing section
breaks, incorrect separators, and some name mismatches.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-10 23:13:45 -07:00
Jozsef Kadlecsik a73f89a61f netfilter: ipset: timeout fixing bug broke SET target special timeout value
The patch "127f559 netfilter: ipset: fix timeout value overflow bug"
broke the SET target when no timeout was specified.

Reported-by: Jean-Philippe Menil <jean-philippe.menil@univ-nantes.fr>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-07-09 10:53:04 +02:00
David S. Miller d3a5ea6e21 Merge branch 'master' of git://1984.lsi.us.es/nf-next 2012-07-07 16:18:50 -07:00
David S. Miller c90a9bb907 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-07-05 03:44:25 -07:00
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
Tomasz Bursztyka 59560a38a3 netfilter: nfnetlink: check callbacks before using those in nfnetlink_rcv_msg
nfnetlink_rcv_msg() might call a NULL callback which will cause NULL pointer
dereference.

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-07-04 19:47:53 +02:00
Pablo Neira Ayuso be0593c678 netfilter: nf_ct_tcp: missing per-net support for cttimeout
This patch adds missing per-net support for the cttimeout
infrastructure to TCP.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
2012-07-04 19:37:42 +02:00
Pablo Neira Ayuso 08911475d1 netfilter: nf_conntrack: generalize nf_ct_l4proto_net
This patch generalizes nf_ct_l4proto_net by splitting it into chunks and
moving the corresponding protocol part to where it really belongs to.

To clarify, note that we follow two different approaches to support per-net
depending if it's built-in or run-time loadable protocol tracker.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
2012-07-04 19:37:22 +02:00
Pablo Neira Ayuso 03292745b0 netlink: add nlk->netlink_bind hook for module auto-loading
This patch adds a hook in the binding path of netlink.

This is used by ctnetlink to allow module autoloading for the case
in which one user executes:

 conntrack -E

So far, this resulted in nfnetlink loaded, but not
nf_conntrack_netlink.

I have received in the past many complains on this behaviour.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-29 16:46:06 -07:00
Pablo Neira Ayuso a31f2d17b3 netlink: add netlink_kernel_cfg parameter to netlink_kernel_create
This patch adds the following structure:

struct netlink_kernel_cfg {
        unsigned int    groups;
        void            (*input)(struct sk_buff *skb);
        struct mutex    *cb_mutex;
};

That can be passed to netlink_kernel_create to set optional configurations
for netlink kernel sockets.

I've populated this structure by looking for NULL and zero parameters at the
existing code. The remaining parameters that always need to be set are still
left in the original interface.

That includes optional parameters for the netlink socket creation. This allows
easy extensibility of this interface in the future.

This patch also adapts all callers to use this new interface.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-29 16:46:02 -07:00
Tomasz Bursztyka 4009e18851 netfilter: nfnetlink: fix missing rcu_read_unlock in nfnetlink_rcv_msg
Bug added in commit 6b75e3e8d6 (netfilter: nfnetlink: add RCU in
nfnetlink_rcv_msg())

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-29 13:04:16 +02:00
Tomasz Bursztyka d31f4d448f netfilter: ipset: fix crash if IPSET_CMD_NONE command is sent
This patch fixes a crash if that ipset command is sent over nfnetlink.

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-29 13:04:04 +02:00
Gao feng 54b8873f7c netfilter: nf_ct_dccp: add dccp_kmemdup_sysctl_table function
This patch is a cleanup. It adds dccp_kmemdup_sysctl_table to
split code into smaller chunks. Yet it prepares introduction
of nf_conntrack_proto_*_sysctl.c.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 19:14:31 +02:00
Gao feng 22ac03772f netfilter: nf_ct_generic: add generic_kmemdup_sysctl_table function
This patch is a cleanup. It adds generic_kmemdup_sysctl_table to
split code into smaller chunks. Yet it prepares introduction
of nf_conntrack_proto_*_sysctl.c.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 19:13:31 +02:00
Gao feng f42c4183c7 netfilter: nf_ct_sctp: merge sctpv[4,6]_net_init into sctp_net_init
Merge sctpv4_net_init and sctpv6_net_init into sctp_net_init to
remove redundant code now that we have the u_int16_t proto
parameter.

And use nf_proto_net.users to identify if it's the first time
we use the nf_proto_net, in that case, we initialize i

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 19:13:31 +02:00
Gao feng 51b4c824fc netfilter: nf_ct_udplite: add udplite_kmemdup_sysctl_table function
This cleans up nf_conntrack_l4proto_udplite[4,6] and it prepares
the moving of the sysctl code to nf_conntrack_proto_*_sysctl.c
to reduce the ifdef pollution.

And use nf_proto_net.users to identify if it's the first time
we use the nf_proto_net, in that case, we initialize it.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 19:12:52 +02:00
Gao feng dee7364e0e netfilter: nf_ct_udp: merge udpv[4,6]_net_init into udp_net_init
Merge udpv4_net_init and udpv6_net_init into udp_net_init to
remove redundant code now that we have the u_int16_t proto
parameter.

And use nf_proto_net.users to identify if it's the first time
we use the nf_proto_net, in that case, we initialize it.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 19:05:33 +02:00
Gao feng efa758fe2c netfilter: nf_ct_tcp: merge tcpv[4,6]_net_init into tcp_net_init
Merge tcpv4_net_init and tcpv6_net_init into tcp_net_init to
remove redundant code now that we have the u_int16_t proto
parameter.

And use nf_proto_net.users to identify if it's the first time
we use the nf_proto_net, in that case, we initialize it.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 19:05:05 +02:00
Gao feng 12c26df35e netfilter: nf_conntrack: fix memory leak if sysctl registration fails
In nf_ct_l4proto_register_sysctl, if l4proto sysctl registration
fails, we have to make sure that we release the compat sysctl
table.

This can happen if TCP has been registered compat for IPv4, and
IPv6 compat registration fails.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 18:55:22 +02:00
Gao feng fa34fff5e6 netfilter: nf_conntrack: use l4proto->users as refcount for per-net data
Currently, nf_proto_net's l4proto->users meaning is quite confusing
since it depends on the compilation tweaks.

To resolve this, we cleanup this code to regard it as the refcount
for l4proto's per-net data, since there may be two l4protos use the
same per-net data.

Thus, we increment pn->users when nf_conntrack_l4proto_register
successfully, and decrement it for nf_conntrack_l4_unregister case.

The users refcnt is not required form layer 3 protocol trackers.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 18:46:00 +02:00
Gao feng f28997e27a netfilter: nf_conntrack: add nf_ct_kfree_compat_sysctl_table
This patch is a cleanup.

It adds nf_ct_kfree_compat_sysctl_table to release l4proto's
compat sysctl table and set the compat sysctl table point to NULL.

This new function will be used by follow-up patches.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 18:36:25 +02:00
Gao feng f1caad2745 netfilter: nf_conntrack: prepare l4proto->init_net cleanup
l4proto->init contain quite redundant code. We can simplify this
by adding a new parameter l3proto.

This patch prepares that code simplification.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 18:31:14 +02:00
Gao feng fa0f61f05e netfilter: nf_conntrack: fix nf_conntrack_l3proto_register
Before commit 2c352f444c
(netfilter: nf_conntrack: prepare namespace support for
l4 protocol trackers), we register sysctl before register
protocol tracker. Thus, if sysctl is registration fails,
the protocol tracker will not be registered.

After that commit, if sysctl registration fails, protocol
registration still remains, so we leave things in intermediate
state.

To fix this, this patch registers sysctl before protocols.
And if protocol registration fail, sysctl is unregistered.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 18:11:15 +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 3da07c0c2b netfilter: nfnetlink_queue_core: Move away from NLMSG_PUT().
And use nlmsg_data() while we're here too.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-26 21:35:27 -07:00
David S. Miller d550d09589 netfilter: nfnetlink_log: Move away from NLMSG_PUT().
And use nlmsg_data() while we're here too.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-26 21:34:03 -07:00
Eric Dumazet c24584c028 netfilter: ipvs: fix dst leak in __ip_vs_addr_is_local_v6
After call to ip6_route_output() we must release dst or we leak it.

Also should test dst->error, as ip6_route_output() never returns NULL.

Use boolean while we are at it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-25 12:07:09 +02:00
Florian Westphal ef5b6e1277 netfilter: ipset: fix interface comparision in hash-netiface sets
ifname_compare() assumes that skb->dev is zero-padded,
e.g 'eth1\0\0\0\0\0...'. This isn't always the case. e1000 driver does

strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1);

in e1000_probe(), so once device is registered dev->name memory contains
'eth1\0:0:3\0\0\0' (or something like that), which makes eth1 compare
fail.

Use plain strcmp() instead.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-25 12:03:21 +02:00
Pablo Neira Ayuso 8e36c4b5b6 netfilter: ctnetlink: fix compilation with NF_CONNTRACK_EVENTS=n
This patch fixes compilation with NF_CONNTRACK_EVENTS=n and
NETFILTER_NETLINK_QUEUE_CT=y.

I'm leaving all those static inline functions that calculate the size
of the event message out of the ifdef area of NF_CONNTRACK_EVENTS since
they will not be included by gcc in case they are unused.

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-23 02:13:46 +02:00
Pablo Neira Ayuso ab5e8b77d5 netfilter: nfnetlink_queue: fix sparse warning due to missing include
This patch fixes a sparse warning due to missing include header file.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-23 02:13:38 +02:00
Pablo Neira Ayuso d584a61a93 netfilter: nfnetlink_queue: fix compilation with CONFIG_NF_NAT=m and CONFIG_NF_CT_NETLINK=y
LD      init/built-in.o
net/built-in.o:(.data+0x4408): undefined reference to `nf_nat_tcp_seq_adjust'
make: *** [vmlinux] Error 1

This patch adds a new pointer hook (nfq_ct_nat_hook) similar to other existing
in Netfilter to solve our complicated configuration dependencies.

Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-22 02:49:52 +02:00
Pablo Neira Ayuso 5a05fae5ca netfilter: nfq_ct_hook needs __rcu and __read_mostly
This removes some sparse warnings.

Reported-by: Fengguang Wu <wfg@linux.intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-20 20:50:31 +02:00
Pablo Neira Ayuso 7c62234547 netfilter: nfnetlink_queue: fix compilation with NF_CONNTRACK disabled
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 <akpm@linux-foundation.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-19 04:44:57 +02:00
Pablo Neira Ayuso 6e9c2db3aa netfilter: fix compilation of the nfnl_cthelper if NF_CONNTRACK is unset
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 <rdunlap@xenotime.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-19 01:25:08 +02:00
Pablo Neira Ayuso 32f5376003 netfilter: nf_ct_helper: disable automatic helper re-assignment of different type
This patch modifies __nf_ct_try_assign_helper in a way that invalidates support
for the following scenario:

1) attach the helper A for first time when the conntrack is created
2) attach new (different) helper B due to changes the reply tuple caused by NAT

eg. port redirection from TCP/21 to TCP/5060 with both FTP and SIP helpers
loaded, which seems to be a quite unorthodox scenario.

I can provide a more elaborated patch to support this scenario but explicit
helper attachment provides a better solution for this since now the use can
attach the helpers consistently, without relying on the automatic helper
lookup magic.

This patch fixes a possible out of bound zeroing of the conntrack helper
extension if the helper B uses more memory for its private data than
helper A.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-19 01:24:52 +02:00
Pablo Neira Ayuso fd7462de46 netfilter: ctnetlink: fix NULL dereference while trying to change helper
The patch 1afc56794e03: "netfilter: nf_ct_helper: implement variable
length helper private data" from Jun 7, 2012, leads to the following
Smatch complaint:

net/netfilter/nf_conntrack_netlink.c:1231 ctnetlink_change_helper()
         error: we previously assumed 'help->helper' could be null (see line 1228)

This NULL dereference can be triggered with the following sequence:

1) attach the helper for first time when the conntrack is created.
2) remove the helper module or detach the helper from the conntrack
   via ctnetlink.
3) attach helper again (the same or different one, no matter) to the
   that existing conntrack again via ctnetlink.

This patch fixes the problem by removing the use case that allows you
to re-assign again a helper for one conntrack entry via ctnetlink since
I cannot find any practical use for it.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-19 00:18:38 +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 8c88f87cb2 netfilter: nfnetlink_queue: add NAT TCP sequence adjustment if packet mangled
User-space programs that receive traffic via NFQUEUE may mangle packets.
If NAT is enabled, this usually puzzles sequence tracking, leading to
traffic disruptions.

With this patch, nfnl_queue will make the corresponding NAT TCP sequence
adjustment if:

1) The packet has been mangled,
2) the NFQA_CFG_F_CONNTRACK flag has been set, and
3) NAT is detected.

There are some records on the Internet complaning about this issue:
http://stackoverflow.com/questions/260757/packet-mangling-utilities-besides-iptables

By now, we only support TCP since we have no helpers for DCCP or SCTP.
Better to add this if we ever have some helper over those layer 4 protocols.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-16 15:09:08 +02:00