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Author SHA1 Message Date
David S. Miller a01aa920b8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter updates for your net-next
tree. A large bunch of code cleanups, simplify the conntrack extension
codebase, get rid of the fake conntrack object, speed up netns by
selective synchronize_net() calls. More specifically, they are:

1) Check for ct->status bit instead of using nfct_nat() from IPVS and
   Netfilter codebase, patch from Florian Westphal.

2) Use kcalloc() wherever possible in the IPVS code, from Varsha Rao.

3) Simplify FTP IPVS helper module registration path, from Arushi Singhal.

4) Introduce nft_is_base_chain() helper function.

5) Enforce expectation limit from userspace conntrack helper,
   from Gao Feng.

6) Add nf_ct_remove_expect() helper function, from Gao Feng.

7) NAT mangle helper function return boolean, from Gao Feng.

8) ctnetlink_alloc_expect() should only work for conntrack with
   helpers, from Gao Feng.

9) Add nfnl_msg_type() helper function to nfnetlink to build the
   netlink message type.

10) Get rid of unnecessary cast on void, from simran singhal.

11) Use seq_puts()/seq_putc() instead of seq_printf() where possible,
    also from simran singhal.

12) Use list_prev_entry() from nf_tables, from simran signhal.

13) Remove unnecessary & on pointer function in the Netfilter and IPVS
    code.

14) Remove obsolete comment on set of rules per CPU in ip6_tables,
    no longer true. From Arushi Singhal.

15) Remove duplicated nf_conntrack_l4proto_udplite4, from Gao Feng.

16) Remove unnecessary nested rcu_read_lock() in
    __nf_nat_decode_session(). Code running from hooks are already
    guaranteed to run under RCU read side.

17) Remove deadcode in nf_tables_getobj(), from Aaron Conole.

18) Remove double assignment in nf_ct_l4proto_pernet_unregister_one(),
    also from Aaron.

19) Get rid of unsed __ip_set_get_netlink(), from Aaron Conole.

20) Don't propagate NF_DROP error to userspace via ctnetlink in
    __nf_nat_alloc_null_binding() function, from Gao Feng.

21) Revisit nf_ct_deliver_cached_events() to remove unnecessary checks,
    from Gao Feng.

22) Kill the fake untracked conntrack objects, use ctinfo instead to
    annotate a conntrack object is untracked, from Florian Westphal.

23) Remove nf_ct_is_untracked(), now obsolete since we have no
    conntrack template anymore, from Florian.

24) Add event mask support to nft_ct, also from Florian.

25) Move nf_conn_help structure to
    include/net/netfilter/nf_conntrack_helper.h.

26) Add a fixed 32 bytes scratchpad area for conntrack helpers.
    Thus, we don't deal with variable conntrack extensions anymore.
    Make sure userspace conntrack helper doesn't go over that size.
    Remove variable size ct extension infrastructure now this code
    got no more clients. From Florian Westphal.

27) Restore offset and length of nf_ct_ext structure to 8 bytes now
    that wraparound is not possible any longer, also from Florian.

28) Allow to get rid of unassured flows under stress in conntrack,
    this applies to DCCP, SCTP and TCP protocols, from Florian.

29) Shrink size of nf_conntrack_ecache structure, from Florian.

30) Use TCP_MAX_WSCALE instead of hardcoded 14 in TCP tracker,
    from Gao Feng.

31) Register SYNPROXY hooks on demand, from Florian Westphal.

32) Use pernet hook whenever possible, instead of global hook
    registration, from Florian Westphal.

33) Pass hook structure to ebt_register_table() to consolidate some
    infrastructure code, from Florian Westphal.

34) Use consume_skb() and return NF_STOLEN, instead of NF_DROP in the
    SYNPROXY code, to make sure device stats are not fooled, patch
    from Gao Feng.

35) Remove NF_CT_EXT_F_PREALLOC this kills quite some code that we
    don't need anymore if we just select a fixed size instead of
    expensive runtime time calculation of this. From Florian.

36) Constify nf_ct_extend_register() and nf_ct_extend_unregister(),
    from Florian.

37) Simplify nf_ct_ext_add(), this kills nf_ct_ext_create(), from
    Florian.

38) Attach NAT extension on-demand from masquerade and pptp helper
    path, from Florian.

39) Get rid of useless ip_vs_set_state_timeout(), from Aaron Conole.

40) Speed up netns by selective calls of synchronize_net(), from
    Florian Westphal.

41) Silence stack size warning gcc in 32-bit arch in snmp helper,
    from Florian.

42) Inconditionally call nf_ct_ext_destroy(), even if we have no
    extensions, to deal with the NF_NAT_MANIP_SRC case. Patch from
    Liping Zhang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-01 10:47:53 -04:00
Liping Zhang 64f3967c7a netfilter: ctnetlink: acquire ct->lock before operating nf_ct_seqadj
We should acquire the ct->lock before accessing or modifying the
nf_ct_seqadj, as another CPU may modify the nf_ct_seqadj at the same
time during its packet proccessing.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-24 20:06:29 +02:00
Liping Zhang 53b56da83d netfilter: ctnetlink: make it safer when updating ct->status
After converting to use rcu for conntrack hash, one CPU may update
the ct->status via ctnetlink, while another CPU may process the
packets and update the ct->status.

So the non-atomic operation "ct->status |= status;" via ctnetlink
becomes unsafe, and this may clear the IPS_DYING_BIT bit set by
another CPU unexpectedly. For example:
         CPU0                            CPU1
  ctnetlink_change_status        __nf_conntrack_find_get
      old = ct->status              nf_ct_gc_expired
          -                         nf_ct_kill
          -                      test_and_set_bit(IPS_DYING_BIT
      new = old | status;                 -
  ct->status = new; <-- oops, _DYING_ is cleared!

Now using a series of atomic bit operation to solve the above issue.

Also note, user shouldn't set IPS_TEMPLATE, IPS_SEQ_ADJUST directly,
so make these two bits be unchangable too.

If we set the IPS_TEMPLATE_BIT, ct will be freed by nf_ct_tmpl_free,
but actually it is alloced by nf_conntrack_alloc.
If we set the IPS_SEQ_ADJUST_BIT, this may cause the NULL pointer
deference, as the nfct_seqadj(ct) maybe NULL.

Last, add some comments to describe the logic change due to the
commit a963d710f3 ("netfilter: ctnetlink: Fix regression in CTA_STATUS
processing"), which makes me feel a little confusing.

Fixes: 76507f69c4 ("[NETFILTER]: nf_conntrack: use RCU for conntrack hash")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-24 20:06:28 +02:00
Liping Zhang 88be4c09d9 netfilter: ctnetlink: fix deadlock due to acquire _expect_lock twice
Currently, ctnetlink_change_conntrack is always protected by _expect_lock,
but this will cause a deadlock when deleting the helper from a conntrack,
as the _expect_lock will be acquired again by nf_ct_remove_expectations:

         CPU0
        ----
  lock(nf_conntrack_expect_lock);
  lock(nf_conntrack_expect_lock);

  *** DEADLOCK ***
  May be due to missing lock nesting notation

  2 locks held by lt-conntrack_gr/12853:
  #0:  (&table[i].mutex){+.+.+.}, at: [<ffffffffa05e2009>]
       nfnetlink_rcv_msg+0x399/0x6a9 [nfnetlink]
  #1:  (nf_conntrack_expect_lock){+.....}, at: [<ffffffffa05f2c1f>]
       ctnetlink_new_conntrack+0x17f/0x408 [nf_conntrack_netlink]

  Call Trace:
   dump_stack+0x85/0xc2
   __lock_acquire+0x1608/0x1680
   ? ctnetlink_parse_tuple_proto+0x10f/0x1c0 [nf_conntrack_netlink]
   lock_acquire+0x100/0x1f0
   ? nf_ct_remove_expectations+0x32/0x90 [nf_conntrack]
   _raw_spin_lock_bh+0x3f/0x50
   ? nf_ct_remove_expectations+0x32/0x90 [nf_conntrack]
   nf_ct_remove_expectations+0x32/0x90 [nf_conntrack]
   ctnetlink_change_helper+0xc6/0x190 [nf_conntrack_netlink]
   ctnetlink_new_conntrack+0x1b2/0x408 [nf_conntrack_netlink]
   nfnetlink_rcv_msg+0x60a/0x6a9 [nfnetlink]
   ? nfnetlink_rcv_msg+0x1b9/0x6a9 [nfnetlink]
   ? nfnetlink_bind+0x1a0/0x1a0 [nfnetlink]
   netlink_rcv_skb+0xa4/0xc0
   nfnetlink_rcv+0x87/0x770 [nfnetlink]

Since the operations are unrelated to nf_ct_expect, so we can drop the
_expect_lock. Also note, after removing the _expect_lock protection,
another CPU may invoke nf_conntrack_helper_unregister, so we should
use rcu_read_lock to protect __nf_conntrack_helper_find invoked by
ctnetlink_change_helper.

Fixes: ca7433df3a ("netfilter: conntrack: seperate expect locking from nf_conntrack_lock")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-24 20:06:28 +02:00
Liping Zhang 14e5676156 netfilter: ctnetlink: drop the incorrect cthelper module request
First, when creating a new ct, we will invoke request_module to try to
load the related inkernel cthelper. So there's no need to call the
request_module again when updating the ct helpinfo.

Second, ctnetlink_change_helper may be called with rcu_read_lock held,
i.e. rcu_read_lock -> nfqnl_recv_verdict -> nfqnl_ct_parse ->
ctnetlink_glue_parse -> ctnetlink_glue_parse_ct ->
ctnetlink_change_helper. But the request_module invocation may sleep,
so we can't call it with the rcu_read_lock held.

Remove it now.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-24 20:06:28 +02:00
David S. Miller 6b6cbc1471 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts were simply overlapping changes.  In the net/ipv4/route.c
case the code had simply moved around a little bit and the same fix
was made in both 'net' and 'net-next'.

In the net/sched/sch_generic.c case a fix in 'net' happened at
the same time that a new argument was added to qdisc_hash_add().

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-15 21:16:30 -04:00
Florian Westphal ab8bc7ed86 netfilter: remove nf_ct_is_untracked
This function is now obsolete and always returns false.
This change has no effect on generated code.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-15 11:51:33 +02:00
Johannes Berg fceb6435e8 netlink: pass extended ACK struct to parsing functions
Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13 13:58:22 -04:00
Liping Zhang 7cddd967bf netfilter: nf_ct_expect: use proper RCU list traversal/update APIs
We should use proper RCU list APIs to manipulate help->expectations,
as we can dump the conntrack's expectations via nfnetlink, i.e. in
ctnetlink_exp_ct_dump_table(), where only rcu_read_lock is acquired.

So for list traversal, use hlist_for_each_entry_rcu; for list add/del,
use hlist_add_head_rcu and hlist_del_rcu.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-08 23:52:17 +02:00
Liping Zhang 207df81501 netfilter: ctnetlink: skip dumping expect when nfct_help(ct) is NULL
For IPCTNL_MSG_EXP_GET, if the CTA_EXPECT_MASTER attr is specified, then
the NLM_F_DUMP request will dump the expectations related to this
connection tracking.

But we forget to check whether the conntrack has nf_conn_help or not,
so if nfct_help(ct) is NULL, oops will happen:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
 IP: ctnetlink_exp_ct_dump_table+0xf9/0x1e0 [nf_conntrack_netlink]
 Call Trace:
  ? ctnetlink_exp_ct_dump_table+0x75/0x1e0 [nf_conntrack_netlink]
  netlink_dump+0x124/0x2a0
  __netlink_dump_start+0x161/0x190
  ctnetlink_dump_exp_ct+0x16c/0x1bc [nf_conntrack_netlink]
  ? ctnetlink_exp_fill_info.constprop.33+0xf0/0xf0 [nf_conntrack_netlink]
  ? ctnetlink_glue_seqadj+0x20/0x20 [nf_conntrack_netlink]
  ctnetlink_get_expect+0x32e/0x370 [nf_conntrack_netlink]
  ? debug_lockdep_rcu_enabled+0x1d/0x20
  nfnetlink_rcv_msg+0x60a/0x6a9 [nfnetlink]
  ? nfnetlink_rcv_msg+0x1b9/0x6a9 [nfnetlink]
  [...]

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-08 23:52:17 +02:00
Liping Zhang 3173d5b8c8 netfilter: ctnetlink: make it safer when checking the ct helper name
One CPU is doing ctnetlink_change_helper(), while another CPU is doing
unhelp() at the same time. So even if help->helper is not NULL at first,
the later statement strcmp(help->helper->name, ...) may still access
the NULL pointer.

So we must use rcu_read_lock and rcu_dereference to avoid such _bad_
thing happen.

Fixes: f95d7a46bc ("netfilter: ctnetlink: Fix regression in CTA_HELP processing")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-08 23:52:16 +02:00
Gao Feng 8b5995d063 netfilter: helper: Add the rcu lock when call __nf_conntrack_helper_find
When invoke __nf_conntrack_helper_find, it needs the rcu lock to
protect the helper module which would not be unloaded.

Now there are two caller nf_conntrack_helper_try_module_get and
ctnetlink_create_expect which don't hold rcu lock. And the other
callers left like ctnetlink_change_helper, ctnetlink_create_conntrack,
and ctnetlink_glue_attach_expect, they already hold the rcu lock
or spin_lock_bh.

Remove the rcu lock in functions nf_ct_helper_expectfn_find_by_name
and nf_ct_helper_expectfn_find_by_symbol. Because they return one pointer
which needs rcu lock, so their caller should hold the rcu lock, not in
these two functions.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-08 23:52:15 +02:00
Liping Zhang 97aae0df1d netfilter: ctnetlink: using bit to represent the ct event
Otherwise, creating a new conntrack via nfnetlink:
  # conntrack -I -p udp -s 1.1.1.1 -d 2.2.2.2 -t 10 --sport 10 --dport 20

will emit the wrong ct events(where UPDATE should be NEW):
  # conntrack -E
  [UPDATE] udp      17 10 src=1.1.1.1 dst=2.2.2.2 sport=10 dport=20
  [UNREPLIED] src=2.2.2.2 dst=1.1.1.1 sport=20 dport=10 mark=0

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-08 23:52:15 +02:00
Pablo Neira Ayuso dedb67c4b4 netfilter: Add nfnl_msg_type() helper function
Add and use nfnl_msg_type() function to replace opencoded nfnetlink
message type. I suggested this change, Arushi Singhal made an initial
patch to address this but was missing several spots.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-07 16:31:36 +02:00
Gao Feng 2c62e0bc68 netfilter: ctnetlink: Expectations must have a conntrack helper area
The expect check function __nf_ct_expect_check() asks the master_help is
necessary. So it is unnecessary to go ahead in ctnetlink_alloc_expect
when there is no help.

Actually the commit bc01befdcf ("netfilter: ctnetlink: add support for
user-space expectation helpers") permits ctnetlink create one expect
even though there is no master help. But the latter commit 3d058d7bc2
("netfilter: rework user-space expectation helper support") disables it
again.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-06 22:01:42 +02:00
David S. Miller 6f14f443d3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Mostly simple cases of overlapping changes (adding code nearby,
a function whose name changes, for example).

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-06 08:24:51 -07:00
Liping Zhang 3b7dabf029 netfilter: invoke synchronize_rcu after set the _hook_ to NULL
Otherwise, another CPU may access the invalid pointer. For example:
    CPU0                CPU1
     -              rcu_read_lock();
     -              pfunc = _hook_;
  _hook_ = NULL;          -
  mod unload              -
     -                 pfunc(); // invalid, panic
     -             rcu_read_unlock();

So we must call synchronize_rcu() to wait the rcu reader to finish.

Also note, in nf_nat_snmp_basic_fini, synchronize_rcu() will be invoked
by later nf_conntrack_helper_unregister, but I'm inclined to add a
explicit synchronize_rcu after set the nf_nat_snmp_hook to NULL. Depend
on such obscure assumptions is not a good idea.

Last, in nfnetlink_cttimeout, we use kfree_rcu to free the time object,
so in cttimeout_exit, invoking rcu_barrier() is not necessary at all,
remove it too.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-27 13:47:28 +02:00
Reshetova, Elena b54ab92b84 netfilter: refcounter conversions
refcount_t type and corresponding API (see include/linux/refcount.h)
should be used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-17 12:49:43 +01:00
Kevin Cernekee f95d7a46bc netfilter: ctnetlink: Fix regression in CTA_HELP processing
Prior to Linux 4.4, it was usually harmless to send a CTA_HELP attribute
containing the name of the current helper.  That is no longer the case:
as of Linux 4.4, if ctnetlink_change_helper() returns an error from
the ct->master check, processing of the request will fail, skipping the
NFQA_EXP attribute (if present).

This patch changes the behavior to improve compatibility with user
programs that expect the kernel interface to work the way it did prior
to Linux 4.4.  If a user program specifies CTA_HELP but the argument
matches the current conntrack helper name, ignore it instead of generating
an error.

Signed-off-by: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-06 12:49:05 +01:00
Kevin Cernekee a963d710f3 netfilter: ctnetlink: Fix regression in CTA_STATUS processing
The libnetfilter_conntrack userland library always sets IPS_CONFIRMED
when building a CTA_STATUS attribute.  If this toggles the bit from
0->1, the parser will return an error.  On Linux 4.4+ this will cause any
NFQA_EXP attribute in the packet to be ignored.  This breaks conntrackd's
userland helpers because they operate on unconfirmed connections.

Instead of returning -EBUSY if the user program asks to modify an
unchangeable bit, simply ignore the change.

Also, fix the logic so that user programs are allowed to clear
the bits that they are allowed to change.

Signed-off-by: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-06 12:48:26 +01:00
Florian Westphal 8e8118f893 netfilter: conntrack: remove packet hotpath stats
These counters sit in hot path and do show up in perf, this is especially
true for 'found' and 'searched' which get incremented for every packet
processed.

Information like

searched=212030105
new=623431
found=333613
delete=623327

does not seem too helpful nowadays:

- on busy systems found and searched will overflow every few hours
(these are 32bit integers), other more busy ones every few days.

- for debugging there are better methods, such as iptables' trace target,
the conntrack log sysctls.  Nowadays we also have perf tool.

This removes packet path stat counters except those that
are expected to be 0 (or close to 0) on a normal system, e.g.
'insert_failed' (race happened) or 'invalid' (proto tracker rejects).

The insert stat is retained for the ctnetlink case.
The found stat is retained for the tuple-is-taken check when NAT has to
determine if it needs to pick a different source address.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-12 19:59:39 +02:00
David S. Miller 60175ccdf4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for your net-next
tree.  Most relevant updates are the removal of per-conntrack timers to
use a workqueue/garbage collection approach instead from Florian
Westphal, the hash and numgen expression for nf_tables from Laura
Garcia, updates on nf_tables hash set to honor the NLM_F_EXCL flag,
removal of ip_conntrack sysctl and many other incremental updates on our
Netfilter codebase.

More specifically, they are:

1) Retrieve only 4 bytes to fetch ports in case of non-linear skb
   transport area in dccp, sctp, tcp, udp and udplite protocol
   conntrackers, from Gao Feng.

2) Missing whitespace on error message in physdev match, from Hangbin Liu.

3) Skip redundant IPv4 checksum calculation in nf_dup_ipv4, from Liping Zhang.

4) Add nf_ct_expires() helper function and use it, from Florian Westphal.

5) Replace opencoded nf_ct_kill() call in IPVS conntrack support, also
   from Florian.

6) Rename nf_tables set implementation to nft_set_{name}.c

7) Introduce the hash expression to allow arbitrary hashing of selector
   concatenations, from Laura Garcia Liebana.

8) Remove ip_conntrack sysctl backward compatibility code, this code has
   been around for long time already, and we have two interfaces to do
   this already: nf_conntrack sysctl and ctnetlink.

9) Use nf_conntrack_get_ht() helper function whenever possible, instead
   of opencoding fetch of hashtable pointer and size, patch from Liping Zhang.

10) Add quota expression for nf_tables.

11) Add number generator expression for nf_tables, this supports
    incremental and random generators that can be combined with maps,
    very useful for load balancing purpose, again from Laura Garcia Liebana.

12) Fix a typo in a debug message in FTP conntrack helper, from Colin Ian King.

13) Introduce a nft_chain_parse_hook() helper function to parse chain hook
    configuration, this is used by a follow up patch to perform better chain
    update validation.

14) Add rhashtable_lookup_get_insert_key() to rhashtable and use it from the
    nft_set_hash implementation to honor the NLM_F_EXCL flag.

15) Missing nulls check in nf_conntrack from nf_conntrack_tuple_taken(),
    patch from Florian Westphal.

16) Don't use the DYING bit to know if the conntrack event has been already
    delivered, instead a state variable to track event re-delivery
    states, also from Florian.

17) Remove the per-conntrack timer, use the workqueue approach that was
    discussed during the NFWS, from Florian Westphal.

18) Use the netlink conntrack table dump path to kill stale entries,
    again from Florian.

19) Add a garbage collector to get rid of stale conntracks, from
    Florian.

20) Reschedule garbage collector if eviction rate is high.

21) Get rid of the __nf_ct_kill_acct() helper.

22) Use ARPHRD_ETHER instead of hardcoded 1 from ARP logger.

23) Make nf_log_set() interface assertive on unsupported families.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-06 12:45:26 -07:00
Florian Westphal 2344d64ec7 netfilter: evict stale entries on netlink dumps
When dumping we already have to look at the entire table, so we might
as well toss those entries whose timeout value is in the past.

We also look at every entry during resize operations.
However, eviction there is not as simple because we hold the
global resize lock so we can't evict without adding a 'expired' list
to drop from later.  Considering that resizes are very rare it doesn't
seem worth doing it.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-30 11:43:09 +02:00
Florian Westphal f330a7fdbe netfilter: conntrack: get rid of conntrack timer
With stats enabled this eats 80 bytes on x86_64 per nf_conn entry, as
Eric Dumazet pointed out during netfilter workshop 2016.

Eric also says: "Another reason was the fact that Thomas was about to
change max timer range [..]" (500462a9de, 'timers: Switch to
a non-cascading wheel').

Remove the timer and use a 32bit jiffies value containing timestamp until
entry is valid.

During conntrack lookup, even before doing tuple comparision, check
the timeout value and evict the entry in case it is too old.

The dying bit is used as a synchronization point to avoid races where
multiple cpus try to evict the same entry.

Because lookup is always lockless, we need to bump the refcnt once
when we evict, else we could try to evict already-dead entry that
is being recycled.

This is the standard/expected way when conntrack entries are destroyed.

Followup patches will introduce garbage colliction via work queue
and further places where we can reap obsoleted entries (e.g. during
netlink dumps), this is needed to avoid expired conntracks from hanging
around for too long when lookup rate is low after a busy period.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-30 11:43:09 +02:00
Florian Westphal d0b35b93d4 netfilter: use_nf_conn_expires helper in more places
... so we don't need to touch all of these places when we get rid of the
timer in nf_conn.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-12 00:43:13 +02:00
Liping Zhang aa0c2c68ab netfilter: ctnetlink: reject new conntrack request with different l4proto
Currently, user can add a conntrack with different l4proto via nfnetlink.
For example, original tuple is TCP while reply tuple is SCTP. This is
invalid combination, we should report EINVAL to userspace.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-09 10:39:26 +02:00
Liping Zhang b18bcb0019 netfilter: nfnetlink_queue: fix memory leak when attach expectation successfully
User can use NFQA_EXP to attach expectations to conntracks, but we
forget to put back nf_conntrack_expect when it is inserted successfully,
i.e. in this normal case, expect's use refcnt will be 3. So even we
unlink it and put it back later, the use refcnt is still 1, then the
memory will be leaked forever.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-09 10:39:25 +02:00
Florian Westphal 23014011ba netfilter: conntrack: support a fixed size of 128 distinct labels
The conntrack label extension is currently variable-sized, e.g. if
only 2 labels are used by iptables rules then the labels->bits[] array
will only contain one element.

We track size of each label storage area in the 'words' member.

But in nftables and openvswitch we always have to ask for worst-case
since we don't know what bit will be used at configuration time.

As most arches are 64bit we need to allocate 24 bytes in this case:

struct nf_conn_labels {
    u8            words;   /*     0     1 */
    /* XXX 7 bytes hole, try to pack */
    long unsigned bits[2]; /*     8     24 */

Make bits a fixed size and drop the words member, it simplifies
the code and only increases memory requirements on x86 when
less than 64bit labels are required.

We still only allocate the extension if its needed.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-22 17:04:55 +02:00
Florian Westphal 0a93aaedc4 netfilter: conntrack: use a single expectation table for all namespaces
We already include netns address in the hash and compare the netns pointers
during lookup, so even if namespaces have overlapping addresses entries
will be spread across the expectation table.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-06 11:50:01 +02:00
Florian Westphal 03d7dc5cdf netfilter: conntrack: check netns when walking expect hash
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-06 11:50:01 +02:00
Florian Westphal 56d52d4892 netfilter: conntrack: use a single hashtable for all namespaces
We already include netns address in the hash and compare the netns pointers
during lookup, so even if namespaces have overlapping addresses entries
will be spread across the table.

Assuming 64k bucket size, this change saves 0.5 mbyte per namespace on a
64bit system.

NAT bysrc and expectation hash is still per namespace, those will
changed too soon.

Future patch will also make conntrack object slab cache global again.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05 16:39:47 +02:00
Florian Westphal e0c7d47221 netfilter: conntrack: check netns when comparing conntrack objects
Once we place all conntracks in the same hash table we must also compare
the netns pointer to skip conntracks that belong to a different namespace.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05 16:39:46 +02:00
David S. Miller 11afbff861 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for your net-next
tree, mostly from Florian Westphal to sort out the lack of sufficient
validation in x_tables and connlabel preparation patches to add
nf_tables support. They are:

1) Ensure we don't go over the ruleset blob boundaries in
   mark_source_chains().

2) Validate that target jumps land on an existing xt_entry. This extra
   sanitization comes with a performance penalty when loading the ruleset.

3) Introduce xt_check_entry_offsets() and use it from {arp,ip,ip6}tables.

4) Get rid of the smallish check_entry() functions in {arp,ip,ip6}tables.

5) Make sure the minimal possible target size in x_tables.

6) Similar to #3, add xt_compat_check_entry_offsets() for compat code.

7) Check that standard target size is valid.

8) More sanitization to ensure that the target_offset field is correct.

9) Add xt_check_entry_match() to validate that matches are well-formed.

10-12) Three patch to reduce the number of parameters in
    translate_compat_table() for {arp,ip,ip6}tables by using a container
    structure.

13) No need to return value from xt_compat_match_from_user(), so make
    it void.

14) Consolidate translate_table() so it can be used by compat code too.

15) Remove obsolete check for compat code, so we keep consistent with
    what was already removed in the native layout code (back in 2007).

16) Get rid of target jump validation from mark_source_chains(),
    obsoleted by #2.

17) Introduce xt_copy_counters_from_user() to consolidate counter
    copying, and use it from {arp,ip,ip6}tables.

18,22) Get rid of unnecessary explicit inlining in ctnetlink for dump
    functions.

19) Move nf_connlabel_match() to xt_connlabel.

20) Skip event notification if connlabel did not change.

21) Update of nf_connlabels_get() to make the upcoming nft connlabel
    support easier.

23) Remove spinlock to read protocol state field in conntrack.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-24 00:12:08 -04:00
Nicolas Dichtel b46f6ded90 libnl: nla_put_be64(): align on a 64-bit area
nla_data() is now aligned on a 64-bit area.

A temporary version (nla_put_be64_32bit()) is added for nla_put_net64().
This function is removed in the next patch.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-23 20:13:24 -04:00
Pablo Neira Ayuso 4a96300cec netfilter: ctnetlink: restore inlining for netlink message size calculation
Calm down gcc warnings:

net/netfilter/nf_conntrack_netlink.c:529:15: warning: 'ctnetlink_proto_size' defined but not used [-Wunused-function]
 static size_t ctnetlink_proto_size(const struct nf_conn *ct)
               ^
net/netfilter/nf_conntrack_netlink.c:546:15: warning: 'ctnetlink_acct_size' defined but not used [-Wunused-function]
 static size_t ctnetlink_acct_size(const struct nf_conn *ct)
               ^
net/netfilter/nf_conntrack_netlink.c:556:12: warning: 'ctnetlink_secctx_size' defined but not used [-Wunused-function]
 static int ctnetlink_secctx_size(const struct nf_conn *ct)
            ^
net/netfilter/nf_conntrack_netlink.c:572:15: warning: 'ctnetlink_timestamp_size' defined but not used [-Wunused-function]
 static size_t ctnetlink_timestamp_size(const struct nf_conn *ct)
               ^

So gcc compiles them out when CONFIG_NF_CONNTRACK_EVENTS and
CONFIG_NETFILTER_NETLINK_GLUE_CT are not set.

Fixes: 4054ff4545 ("netfilter: ctnetlink: remove unnecessary inlining")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2016-04-18 22:14:40 +02:00
Pablo Neira Ayuso 4054ff4545 netfilter: ctnetlink: remove unnecessary inlining
Many of these functions are called from control plane path.  Move
ctnetlink_nlmsg_size() under CONFIG_NF_CONNTRACK_EVENTS to avoid a
compilation warning when CONFIG_NF_CONNTRACK_EVENTS=n.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-14 00:39:34 +02:00
Sasha Levin b16c29191d netfilter: nf_conntrack: use safer way to lock all buckets
When we need to lock all buckets in the connection hashtable we'd attempt to
lock 1024 spinlocks, which is way more preemption levels than supported by
the kernel. Furthermore, this behavior was hidden by checking if lockdep is
enabled, and if it was - use only 8 buckets(!).

Fix this by using a global lock and synchronize all buckets on it when we
need to lock them all. This is pretty heavyweight, but is only done when we
need to resize the hashtable, and that doesn't happen often enough (or at all).

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-01-20 14:15:31 +01:00
Pablo Neira Ayuso 7b8002a151 netfilter: nfnetlink: pass down netns pointer to call() and call_rcu()
Adapt callsites to avoid recurrent lookup of the netns pointer.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-12-28 18:41:41 +01:00
Ken-ichirou MATSUZAWA 224a05975e netfilter: ctnetlink: add const qualifier to nfnl_hook.get_ct
get_ct as is and will not update its skb argument, and users of
nfnl_ct_hook is currently only nfqueue, we can add const qualifier.

Signed-off-by: Ken-ichirou MATSUZAWA <chamas@h4.dion.ne.jp>
2015-10-05 17:32:13 +02:00
Ken-ichirou MATSUZAWA 83f3e94d34 netfilter: Kconfig rename QUEUE_CT to GLUE_CT
Conntrack information attaching infrastructure is now generic and
update it's name to use `glue' in previous patch. This patch updates
Kconfig symbol name and adding NF_CT_NETLINK dependency.

Signed-off-by: Ken-ichirou MATSUZAWA <chamas@h4.dion.ne.jp>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-05 17:32:12 +02:00
Ken-ichirou MATSUZAWA a4b4766c3c netfilter: nfnetlink_queue: rename related to nfqueue attaching conntrack info
The idea of this series of patch is to attach conntrack information to
nflog like nfqueue has already done. nfqueue conntrack info attaching
basis is generic, rename those names to generic one, glue.

Signed-off-by: Ken-ichirou MATSUZAWA <chamas@h4.dion.ne.jp>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-05 17:32:11 +02:00
Pablo Neira Ayuso b7bd1809e0 netfilter: nfnetlink_queue: get rid of nfnetlink_queue_ct.c
The original intention was to avoid dependencies between nfnetlink_queue and
conntrack without ifdef pollution. However, we can achieve this by moving the
conntrack dependent code into ctnetlink and keep some glue code to access the
nfq_ct indirection from nfqueue.

After this patch, the nfq_ct indirection is always compiled in the netfilter
core to avoid polluting nfqueue with ifdefs. Thus, if nf_conntrack is not
compiled this results in only 8-bytes of memory waste in x86_64.

This patch also adds ctnetlink_nfqueue_seqadj() to avoid that the nf_conn
structure layout if exposed to nf_queue, which creates another dependency with
nf_conntrack at compilation time.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-04 21:45:44 +02:00
Daniel Borkmann 5e8018fc61 netfilter: nf_conntrack: add efficient mark to zone mapping
This work adds the possibility of deriving the zone id from the skb->mark
field in a scalable manner. This allows for having only a single template
serving hundreds/thousands of different zones, for example, instead of the
need to have one match for each zone as an extra CT jump target.

Note that we'd need to have this information attached to the template as at
the time when we're trying to lookup a possible ct object, we already need
to know zone information for a possible match when going into
__nf_conntrack_find_get(). This work provides a minimal implementation for
a possible mapping.

In order to not add/expose an extra ct->status bit, the zone structure has
been extended to carry a flag for deriving the mark.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-18 01:24:05 +02:00
Daniel Borkmann deedb59039 netfilter: nf_conntrack: add direction support for zones
This work adds a direction parameter to netfilter zones, so identity
separation can be performed only in original/reply or both directions
(default). This basically opens up the possibility of doing NAT with
conflicting IP address/port tuples from multiple, isolated tenants
on a host (e.g. from a netns) without requiring each tenant to NAT
twice resp. to use its own dedicated IP address to SNAT to, meaning
overlapping tuples can be made unique with the zone identifier in
original direction, where the NAT engine will then allocate a unique
tuple in the commonly shared default zone for the reply direction.
In some restricted, local DNAT cases, also port redirection could be
used for making the reply traffic unique w/o requiring SNAT.

The consensus we've reached and discussed at NFWS and since the initial
implementation [1] was to directly integrate the direction meta data
into the existing zones infrastructure, as opposed to the ct->mark
approach we proposed initially.

As we pass the nf_conntrack_zone object directly around, we don't have
to touch all call-sites, but only those, that contain equality checks
of zones. Thus, based on the current direction (original or reply),
we either return the actual id, or the default NF_CT_DEFAULT_ZONE_ID.
CT expectations are direction-agnostic entities when expectations are
being compared among themselves, so we can only use the identifier
in this case.

Note that zone identifiers can not be included into the hash mix
anymore as they don't contain a "stable" value that would be equal
for both directions at all times, f.e. if only zone->id would
unconditionally be xor'ed into the table slot hash, then replies won't
find the corresponding conntracking entry anymore.

If no particular direction is specified when configuring zones, the
behaviour is exactly as we expect currently (both directions).

Support has been added for the CT netlink interface as well as the
x_tables raw CT target, which both already offer existing interfaces
to user space for the configuration of zones.

Below a minimal, simplified collision example (script in [2]) with
netperf sessions:

  +--- tenant-1 ---+   mark := 1
  |    netperf     |--+
  +----------------+  |                CT zone := mark [ORIGINAL]
   [ip,sport] := X   +--------------+  +--- gateway ---+
                     | mark routing |--|     SNAT      |-- ... +
                     +--------------+  +---------------+       |
  +--- tenant-2 ---+  |                                     ~~~|~~~
  |    netperf     |--+                +-----------+           |
  +----------------+   mark := 2       | netserver |------ ... +
   [ip,sport] := X                     +-----------+
                                        [ip,port] := Y
On the gateway netns, example:

  iptables -t raw -A PREROUTING -j CT --zone mark --zone-dir ORIGINAL
  iptables -t nat -A POSTROUTING -o <dev> -j SNAT --to-source <ip> --random-fully

  iptables -t mangle -A PREROUTING -m conntrack --ctdir ORIGINAL -j CONNMARK --save-mark
  iptables -t mangle -A POSTROUTING -m conntrack --ctdir REPLY -j CONNMARK --restore-mark

conntrack dump from gateway netns:

  netperf -H 10.1.1.2 -t TCP_STREAM -l60 -p12865,5555 from each tenant netns

  tcp 6 431995 ESTABLISHED src=40.1.1.1 dst=10.1.1.2 sport=5555 dport=12865 zone-orig=1
                           src=10.1.1.2 dst=10.1.1.1 sport=12865 dport=1024
               [ASSURED] mark=1 secctx=system_u:object_r:unlabeled_t:s0 use=1

  tcp 6 431994 ESTABLISHED src=40.1.1.1 dst=10.1.1.2 sport=5555 dport=12865 zone-orig=2
                           src=10.1.1.2 dst=10.1.1.1 sport=12865 dport=5555
               [ASSURED] mark=2 secctx=system_u:object_r:unlabeled_t:s0 use=1

  tcp 6 299 ESTABLISHED src=40.1.1.1 dst=10.1.1.2 sport=39438 dport=33768 zone-orig=1
                        src=10.1.1.2 dst=10.1.1.1 sport=33768 dport=39438
               [ASSURED] mark=1 secctx=system_u:object_r:unlabeled_t:s0 use=1

  tcp 6 300 ESTABLISHED src=40.1.1.1 dst=10.1.1.2 sport=32889 dport=40206 zone-orig=2
                        src=10.1.1.2 dst=10.1.1.1 sport=40206 dport=32889
               [ASSURED] mark=2 secctx=system_u:object_r:unlabeled_t:s0 use=2

Taking this further, test script in [2] creates 200 tenants and runs
original-tuple colliding netperf sessions each. A conntrack -L dump in
the gateway netns also confirms 200 overlapping entries, all in ESTABLISHED
state as expected.

I also did run various other tests with some permutations of the script,
to mention some: SNAT in random/random-fully/persistent mode, no zones (no
overlaps), static zones (original, reply, both directions), etc.

  [1] http://thread.gmane.org/gmane.comp.security.firewalls.netfilter.devel/57412/
  [2] https://paste.fedoraproject.org/242835/65657871/

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-18 01:22:50 +02:00
Daniel Borkmann 308ac9143e netfilter: nf_conntrack: push zone object into functions
This patch replaces the zone id which is pushed down into functions
with the actual zone object. It's a bigger one-time change, but
needed for later on extending zones with a direction parameter, and
thus decoupling this additional information from all call-sites.

No functional changes in this patch.

The default zone becomes a global const object, namely nf_ct_zone_dflt
and will be returned directly in various cases, one being, when there's
f.e. no zoning support.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-11 12:29:01 +02:00
Pablo Neira Ayuso 95dd8653de netfilter: ctnetlink: put back references to master ct and expect objects
We have to put back the references to the master conntrack and the expectation
that we just created, otherwise we'll leak them.

Fixes: 0ef71ee1a5 ("netfilter: ctnetlink: refactor ctnetlink_create_expect")
Reported-by: Tim Wiess <Tim.Wiess@watchguard.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-10 14:18:03 +02:00
Kristian Evensen 866476f323 netfilter: conntrack: Flush connections with a given mark
This patch adds support for selective flushing of conntrack mappings.
By adding CTA_MARK and CTA_MARK_MASK to a delete-message, the mark (and
mask) is checked before a connection is deleted while flushing.

Configuring the flush is moved out of ctnetlink_del_conntrack(), and
instead of calling nf_conntrack_flush_report(), we always call
nf_ct_iterate_cleanup().  This enables us to only make one call from the
new ctnetlink_flush_conntrack() and makes it easy to add more filter
parameters.

Filtering is done in the ctnetlink_filter_match()-function, which is
also called from ctnetlink_dump_table(). ctnetlink_dump_filter has been
renamed ctnetlink_filter, to indicated that it is no longer only used
when dumping conntrack entries.

Moreover, reject mark filters with -EOPNOTSUPP if no ct mark support is
available.

Signed-off-by: Kristian Evensen <kristian.evensen@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-01-08 12:14:20 +01:00
Eric Dumazet d2de875c6d net: use ktime_get_ns() and ktime_get_real_ns() helpers
ktime_get_ns() replaces ktime_to_ns(ktime_get())

ktime_get_real_ns() replaces ktime_to_ns(ktime_get_real())

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-22 19:57:23 -07:00
David S. Miller a8138f42d4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains updates for your net-next tree,
they are:

1) Use kvfree() helper function from x_tables, from Eric Dumazet.

2) Remove extra timer from the conntrack ecache extension, use a
   workqueue instead to redeliver lost events to userspace instead,
   from Florian Westphal.

3) Removal of the ulog targets for ebtables and iptables. The nflog
   infrastructure superseded this almost 9 years ago, time to get rid
   of this code.

4) Replace the list of loggers by an array now that we can only have
   two possible non-overlapping logger flavours, ie. kernel ring buffer
   and netlink logging.

5) Move Eric Dumazet's log buffer code to nf_log to reuse it from
   all of the supported per-family loggers.

6) Consolidate nf_log_packet() as an unified interface for packet logging.
   After this patch, if the struct nf_loginfo is available, it explicitly
   selects the logger that is used.

7) Move ip and ip6 logging code from xt_LOG to the corresponding
   per-family loggers. Thus, x_tables and nf_tables share the same code
   for packet logging.

8) Add generic ARP packet logger, which is used by nf_tables. The
   format aims to be consistent with the output of xt_LOG.

9) Add generic bridge packet logger. Again, this is used by nf_tables
   and it routes the packets to the real family loggers. As a result,
   we get consistent logging format for the bridge family. The ebt_log
   logging code has been intentionally left in place not to break
   backward compatibility since the logging output differs from xt_LOG.

10) Update nft_log to explicitly request the required family logger when
    needed.

11) Finish nft_log so it supports arp, ip, ip6, bridge and inet families.
    Allowing selection between netlink and kernel buffer ring logging.

12) Several fixes coming after the netfilter core logging changes spotted
    by robots.

13) Use IS_ENABLED() macros whenever possible in the netfilter tree,
    from Duan Jiong.

14) Removal of a couple of unnecessary branch before kfree, from Fabian
    Frederick.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-20 21:01:43 -07:00
Fabian Frederick 397304b52d netfilter: ctnetlink: remove null test before kfree
Fix checkpatch warning:
WARNING: kfree(NULL) is safe this check is probably not required

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-06-25 14:49:38 +02:00
Ken-ichirou MATSUZAWA 4a001068d7 netfilter: ctnetlink: add zone size to length
Signed-off-by: Ken-ichirou MATSUZAWA <chamas@h4.dion.ne.jp>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-06-16 13:53:03 +02:00
Florian Westphal cd5f336f17 netfilter: ctnetlink: fix refcnt leak in dying/unconfirmed list dumper
'last' keeps track of the ct that had its refcnt bumped during previous
dump cycle.  Thus it must not be overwritten until end-of-function.

Another (unrelated, theoretical) issue: Don't attempt to bump refcnt of a conntrack
whose reference count is already 0.  Such conntrack is being destroyed
right now, its memory is freed once we release the percpu dying spinlock.

Fixes: b7779d06 ('netfilter: conntrack: spinlock per cpu to protect special lists.')
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-06-16 12:51:36 +02:00
Pablo Neira Ayuso 266155b2de netfilter: ctnetlink: fix dumping of dying/unconfirmed conntracks
The dumping prematurely stops, it seems the callback argument that
indicates that all entries have been dumped is set after iterating
on the first cpu list. The dumping also may stop before the entire
per-cpu list content is also dumped.

With this patch, conntrack -L dying now shows the dying list content
again.

Fixes: b7779d06 ("netfilter: conntrack: spinlock per cpu to protect special lists.")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-06-16 12:51:35 +02:00
Florian Westphal fe337ac283 netfilter: ctnetlink: don't add null bindings if no nat requested
commit 0eba801b64 tried to fix a race
where nat initialisation can happen after ctnetlink-created conntrack
has been created.

However, it causes the nat module(s) to be loaded needlessly on
systems that are not using NAT.

Fortunately, we do not have to create null bindings in that case.

conntracks injected via ctnetlink always have the CONFIRMED bit set,
which prevents addition of the nat extension in nf_nat_ipv4/6_fn().

We only need to make sure that either no nat extension is added
or that we've created both src and dst manips.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-04-29 20:49:08 +02:00
David S. Miller e86e180b82 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter/IPVS updates for net-next,
most relevantly they are:

* cleanup to remove double semicolon from stephen hemminger.

* calm down sparse warning in xt_ipcomp, from Fan Du.

* nf_ct_labels support for nf_tables, from Florian Westphal.

* new macros to simplify rcu dereferences in the scope of nfnetlink
  and nf_tables, from Patrick McHardy.

* Accept queue and drop (including reason for drop) to verdict
  parsing in nf_tables, also from Patrick.

* Remove unused random seed initialization in nfnetlink_log, from
  Florian Westphal.

* Allow to attach user-specific information to nf_tables rules, useful
  to attach user comments to rule, from me.

* Return errors in ipset according to the manpage documentation, from
  Jozsef Kadlecsik.

* Fix coccinelle warnings related to incorrect bool type usage for ipset,
  from Fengguang Wu.

* Add hash:ip,mark set type to ipset, from Vytas Dauksa.

* Fix message for each spotted by ipset for each netns that is created,
  from Ilia Mirkin.

* Add forceadd option to ipset, which evicts a random entry from the set
  if it becomes full, from Josh Hunt.

* Minor IPVS cleanups and fixes from Andi Kleen and Tingwei Liu.

* Improve conntrack scalability by removing a central spinlock, original
  work from Eric Dumazet. Jesper Dangaard Brouer took them over to address
  remaining issues. Several patches to prepare this change come in first
  place.

* Rework nft_hash to resolve bugs (leaking chain, missing rcu synchronization
  on element removal, etc. from Patrick McHardy.

* Restore context in the rule deletion path, as we now release rule objects
  synchronously, from Patrick McHardy. This gets back event notification for
  anonymous sets.

* Fix NAT family validation in nft_nat, also from Patrick.

* Improve scalability of xt_connlimit by using an array of spinlocks and
  by introducing a rb-tree of hashtables for faster lookup of accounted
  objects per network. This patch was preceded by several patches and
  refactorizations to accomodate this change including the use of kmem_cache,
  from Florian Westphal.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-17 15:06:24 -04:00
Jesper Dangaard Brouer 93bb0ceb75 netfilter: conntrack: remove central spinlock nf_conntrack_lock
nf_conntrack_lock is a monolithic lock and suffers from huge contention
on current generation servers (8 or more core/threads).

Perf locking congestion is clear on base kernel:

-  72.56%  ksoftirqd/6  [kernel.kallsyms]    [k] _raw_spin_lock_bh
   - _raw_spin_lock_bh
      + 25.33% init_conntrack
      + 24.86% nf_ct_delete_from_lists
      + 24.62% __nf_conntrack_confirm
      + 24.38% destroy_conntrack
      + 0.70% tcp_packet
+   2.21%  ksoftirqd/6  [kernel.kallsyms]    [k] fib_table_lookup
+   1.15%  ksoftirqd/6  [kernel.kallsyms]    [k] __slab_free
+   0.77%  ksoftirqd/6  [kernel.kallsyms]    [k] inet_getpeer
+   0.70%  ksoftirqd/6  [nf_conntrack]       [k] nf_ct_delete
+   0.55%  ksoftirqd/6  [ip_tables]          [k] ipt_do_table

This patch change conntrack locking and provides a huge performance
improvement.  SYN-flood attack tested on a 24-core E5-2695v2(ES) with
10Gbit/s ixgbe (with tool trafgen):

 Base kernel:   810.405 new conntrack/sec
 After patch: 2.233.876 new conntrack/sec

Notice other floods attack (SYN+ACK or ACK) can easily be deflected using:
 # iptables -A INPUT -m state --state INVALID -j DROP
 # sysctl -w net/netfilter/nf_conntrack_tcp_loose=0

Use an array of hashed spinlocks to protect insertions/deletions of
conntracks into the hash table. 1024 spinlocks seem to give good
results, at minimal cost (4KB memory). Due to lockdep max depth,
1024 becomes 8 if CONFIG_LOCKDEP=y

The hash resize is a bit tricky, because we need to take all locks in
the array. A seqcount_t is used to synchronize the hash table users
with the resizing process.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-03-07 11:41:13 +01:00
Jesper Dangaard Brouer ca7433df3a netfilter: conntrack: seperate expect locking from nf_conntrack_lock
Netfilter expectations are protected with the same lock as conntrack
entries (nf_conntrack_lock).  This patch split out expectations locking
to use it's own lock (nf_conntrack_expect_lock).

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-03-07 11:41:01 +01:00
Jesper Dangaard Brouer b7779d06f9 netfilter: conntrack: spinlock per cpu to protect special lists.
One spinlock per cpu to protect dying/unconfirmed/template special lists.
(These lists are now per cpu, a bit like the untracked ct)
Add a @cpu field to nf_conn, to make sure we hold the appropriate
spinlock at removal time.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-03-07 11:40:38 +01:00
Florian Westphal d2bf2f34cc netfilter: nft_ct: labels get support
This also adds NF_CT_LABELS_MAX_SIZE so it can be re-used
as BUILD_BUG_ON in nft_ct.

At this time, nft doesn't yet support writing to the label area;
when this changes the label->words handling needs to be moved
out of xt_connlabel.c into nf_conntrack_labels.c.

Also removes a useless run-time check: words cannot grow beyond
4 (32 bit) or 2 (64bit) since xt_connlabel enforces a maximum of
128 labels.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-02-19 11:41:25 +01:00
Pablo Neira Ayuso 0eba801b64 netfilter: ctnetlink: force null nat binding on insert
Quoting Andrey Vagin:
  When a conntrack is created  by kernel, it is initialized (sets
  IPS_{DST,SRC}_NAT_DONE_BIT bits in nf_nat_setup_info) and only then it
  is added in hashes (__nf_conntrack_hash_insert), so one conntract
  can't be initialized from a few threads concurrently.

  ctnetlink can add an uninitialized conntrack (w/o
  IPS_{DST,SRC}_NAT_DONE_BIT) in hashes, then a few threads can look up
  this conntrack and start initialize it concurrently. It's dangerous,
  because BUG can be triggered from nf_nat_setup_info.

Fix this race by always setting up nat, even if no CTA_NAT_ attribute
was requested before inserting the ct into the hash table. In absence
of CTA_NAT_ attribute, a null binding is created.

This alters current behaviour: Before this patch, the first packet
matching the newly injected conntrack would be run through the nat
table since nf_nat_initialized() returns false.  IOW, this forces
ctnetlink users to specify the desired nat transformation on ct
creation time.

Thanks for Florian Westphal, this patch is based on his original
patch to address this problem, including this patch description.

Reported-By: Andrey Vagin <avagin@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Florian Westphal <fw@strlen.de>
2014-02-18 00:13:51 +01:00
Florian Westphal 534473c608 netfilter: ctnetlink: honor CTA_MARK_MASK when setting ctmark
Useful to only set a particular range of the conntrack mark while
leaving exisiting parts of the value alone, e.g. when setting
conntrack marks via NFQUEUE.

Follows same scheme as MARK/CONNMARK targets, i.e. the mask defines
those bits that should be altered.  No mask is equal to '~0', ie.
the old value is replaced by new one.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-12-20 10:21:42 +01:00
Holger Eitzenberger 4542fa4727 netfilter: ctnetlink: account both directions in one step
With the intent to dump other accounting data later.
This patch is a cleanup.

Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-11-03 21:49:32 +01:00
Holger Eitzenberger f7b13e4330 netfilter: introduce nf_conn_acct structure
Encapsulate counters for both directions into nf_conn_acct. During
that process also consistently name pointers to the extend 'acct',
not 'counters'. This patch is a cleanup.

Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-11-03 21:48:49 +01:00
Florian Westphal b7e092c05b netfilter: ctnetlink: fix uninitialized variable
net/netfilter/nf_conntrack_netlink.c: In function 'ctnetlink_nfqueue_attach_expect':
'helper' may be used uninitialized in this function

It was only initialized in if CTA_EXPECT_HELP_NAME attribute was
present, it must be NULL otherwise.

Problem added recently in bd077937
(netfilter: nfnetlink_queue: allow to attach expectations to conntracks).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-08-28 00:28:19 +02:00
Patrick McHardy 41d73ec053 netfilter: nf_conntrack: make sequence number adjustments usuable without NAT
Split out sequence number adjustments from NAT and move them to the conntrack
core to make them usable for SYN proxying. The sequence number adjustment
information is moved to a seperate extend. The extend is added to new
conntracks when a NAT mapping is set up for a connection using a helper.

As a side effect, this saves 24 bytes per connection with NAT in the common
case that a connection does not have a helper assigned.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Tested-by: Martin Topholm <mph@one.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-08-28 00:26:48 +02:00
Pablo Neira Ayuso bd07793705 netfilter: nfnetlink_queue: allow to attach expectations to conntracks
This patch adds the capability to attach expectations via nfnetlink_queue.
This is required by conntrack helpers that trigger expectations based on
the first packet seen like the TFTP and the DHCPv6 user-space helpers.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-08-13 16:32:10 +02:00
Pablo Neira Ayuso 0ef71ee1a5 netfilter: ctnetlink: refactor ctnetlink_create_expect
This patch refactors ctnetlink_create_expect by spliting it in two
chunks. As a result, we have a new function ctnetlink_alloc_expect
to allocate and to setup the expectation from ctnetlink.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-08-13 15:48:20 +02:00
Florian Westphal 02982c27ba netfilter: nf_conntrack: remove duplicate code in ctnetlink
ctnetlink contains copy-paste code from death_by_timeout.  In order to
avoid changing both places in upcoming event delivery patch,
export death_by_timeout functionality and use it in the ctnetlink code.

Based on earlier patch from Pablo Neira.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-07-31 18:51:23 +02:00
David S. Miller 0c1072ae02 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/freescale/fec_main.c
	drivers/net/ethernet/renesas/sh_eth.c
	net/ipv4/gre.c

The GRE conflict is between a bug fix (kfree_skb --> kfree_skb_list)
and the splitting of the gre.c code into seperate files.

The FEC conflict was two sets of changes adding ethtool support code
in an "!CONFIG_M5272" CPP protected block.

Finally the sh_eth.c conflict was between one commit add bits set
in the .eesr_err_check mask whilst another commit removed the
.tx_error_check member and assignments.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-03 14:55:13 -07:00
Florian Westphal 797a7d66d2 netfilter: ctnetlink: send event when conntrack label was modified
commit 0ceabd8387
(netfilter: ctnetlink: deliver labels to userspace) sets the event bit
when we raced with another packet, instead of raising the event bit
when the label bit is set for the first time.

commit 9b21f6a909
(netfilter: ctnetlink: allow userspace to modify labels) forgot to update
the event mask in the "conntrack already exists" case.

Both issues result in CTA_LABELS attribute not getting included in the
conntrack event.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-06-24 11:32:56 +02:00
Daniel Borkmann 130ffbc263 netfilter: check return code from nla_parse_tested
These are the only calls under net/ that do not check nla_parse_nested()
for its error code, but simply continue execution. If parsing of netlink
attributes fails, we should return with an error instead of continuing.
In nearly all of these calls we have a policy attached, that is being
type verified during nla_parse_nested(), which we would miss checking
for otherwise.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-06-20 11:20:13 +02:00
Pablo Neira Ayuso e844a92843 netfilter: ctnetlink: allow to dump expectation per master conntrack
This patch adds the ability to dump all existing expectations
per master conntrack.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-03-19 17:02:18 +01:00
Sasha Levin b67bfe0d42 hlist: drop the node parameter from iterators
I'm not sure why, but the hlist for each entry iterators were conceived

        list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

        hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

 - Fix up the actual hlist iterators in linux/list.h
 - Fix up the declaration of other iterators based on the hlist ones.
 - A very small amount of places were using the 'node' parameter, this
 was modified to use 'obj->member' instead.
 - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
 properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
    <+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
    ...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:24 -08:00
David S. Miller 2ccba5433b Merge branch 'master' of git://1984.lsi.us.es/nf-next
Pablo Neira Ayuso says:

====================
The following patchset contain updates for your net-next tree, they are:

* Fix (for just added) connlabel dependencies, from Florian Westphal.

* Add aliasing support for conntrack, thus users can either use -m state
  or -m conntrack from iptables while using the same kernel module, from
  Jozsef Kadlecsik.

* Some code refactoring for the CT target to merge common code in
  revision 0 and 1, from myself.

* Add aliasing support for CT, based on patch from Jozsef Kadlecsik.

* Add one mutex per nfnetlink subsystem, from myself.

* Improved logging for packets that are dropped by helpers, from myself.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-18 23:42:09 -05:00
David S. Miller 6338a53a2b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net into net
Pull in 'net' to take in the bug fixes that didn't make it into
3.8-final.

Also, deal with the semantic conflict of the change made to
net/ipv6/xfrm6_policy.c   A missing rt6->n neighbour release
was added to 'net', but in 'net-next' we no longer cache the
neighbour entries in the ipv6 routes so that change is not
appropriate there.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-18 23:34:21 -05:00
Florian Westphal 442fad9423 netfilter: ctnetlink: don't permit ct creation with random tuple
Userspace can cause kernel panic by not specifying orig/reply
tuple: kernel will create a tuple with random stack values.

Problem is that tuple.dst.dir will be random, too, which
causes nf_ct_tuplehash_to_ctrack() to return garbage.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@gnumonks.org>
2013-02-12 23:18:15 +01:00
Pablo Neira Ayuso c14b78e7de netfilter: nfnetlink: add mutex per subsystem
This patch replaces the global lock to one lock per subsystem.
The per-subsystem lock avoids that processes operating
with different subsystems are synchronized.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-02-05 04:07:35 +01:00
Florian Westphal 9b21f6a909 netfilter: ctnetlink: allow userspace to modify labels
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>
2013-01-18 00:28:17 +01:00
Florian Westphal 0ceabd8387 netfilter: ctnetlink: deliver labels to userspace
Introduce CTA_LABELS attribute to send a bit-vector of currently active labels
to userspace.

Future patch will permit userspace to also set/delete active labels.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-18 00:28:16 +01:00
Florian Westphal c539f01717 netfilter: add connlabel conntrack extension
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>
2013-01-18 00:28:15 +01:00
Jesper Juhl 1310b955c8 netfilter: ctnetlink: fix leak in error path of ctnetlink_create_expect
This patch fixes a leak in one of the error paths of
ctnetlink_create_expect if no helper and no timeout is specified.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-12-26 23:02:09 +01:00
Florian Westphal 6d1fafcaec netfilter: ctnetlink: nla_policy updates
Add stricter checking for a few attributes.
Note that these changes don't fix any bug in the current code base.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-12-03 15:13:10 +01:00
Pablo Neira Ayuso d871befe35 netfilter: ctnetlink: dump entries from the dying and unconfirmed lists
This patch adds a new operation to dump the content of the dying and
unconfirmed lists.

Under some situations, the global conntrack counter can be inconsistent
with the number of entries that we can dump from the conntrack table.
The way to resolve this is to allow dumping the content of the unconfirmed
and dying lists, so far it was not possible to look at its content.

This provides some extra instrumentation to resolve problematic situations
in which anyone suspects memory leaks.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-12-03 15:06:52 +01:00
Pablo Neira Ayuso 04dac0111d netfilter: nf_conntrack: improve nf_conn object traceability
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>
2012-12-03 15:06:33 +01:00
Pablo Neira Ayuso 7be54ca476 netfilter: nf_ct_ftp: add sequence tracking pickup facility for injected entries
This patch allows the FTP helper to pickup the sequence tracking from
the first packet seen. This is useful to fix the breakage of the first
FTP command after the failover while using conntrackd to synchronize
states.

The seq_aft_nl_num field in struct nf_ct_ftp_info has been shrinked to
16-bits (enough for what it does), so we can use the remaining 16-bits
to store the flags while using the same size for the private FTP helper
data.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-09-24 14:29:40 +02:00
David S. Miller b0e61d98c6 Merge branch 'master' of git://1984.lsi.us.es/nf-next
Pablo Neira Ayuso says:

====================
The following patchset contains four Netfilter updates, mostly targeting
to fix issues added with IPv6 NAT, and one little IPVS update for net-next:

* Remove unneeded conditional free of skb in nfnetlink_queue, from
  Wei Yongjun.

* One semantic path from coccinelle detected the use of list_del +
  INIT_LIST_HEAD, instead of list_del_init, again from Wei Yongjun.

* Fix out-of-bound memory access in the NAT address selection, from
  Florian Westphal. This was introduced with the IPv6 NAT patches.

* Two fixes for crashes that were introduced in the recently merged
  IPv6 NAT support, from myself.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-13 14:24:31 -04:00
Pablo Neira Ayuso c7cbb9173d netfilter: ctnetlink: fix module auto-load in ctnetlink_parse_nat
(c7232c9 netfilter: add protocol independent NAT core) added
incorrect locking for the module auto-load case in ctnetlink_parse_nat.

That function is always called from ctnetlink_create_conntrack which
requires no locking.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-09-12 17:27:37 +02:00
Eric W. Biederman 15e473046c netlink: Rename pid to portid to avoid confusion
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>
2012-09-10 15:30:41 -04:00
Pablo Neira Ayuso ace1fe1231 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
This merges (3f509c6 netfilter: nf_nat_sip: fix incorrect handling
of EBUSY for RTCP expectation) to Patrick McHardy's IPv6 NAT changes.
2012-09-03 15:34:51 +02:00
Julia Lawall ef6acf68c2 netfilter: ctnetlink: fix error return code in init path
Initialize return variable before exiting on an error path.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}

// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-08-30 03:28:22 +02:00
Patrick McHardy c7232c9979 netfilter: add protocol independent NAT core
Convert the IPv4 NAT implementation to a protocol independent core and
address family specific modules.

Signed-off-by: Patrick McHardy <kaber@trash.net>
2012-08-30 03:00:14 +02:00
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
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
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 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 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 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
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
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