Commit Graph

102 Commits

Author SHA1 Message Date
Jeremy Sowden
40d102cde0 netfilter: update include directives.
Include some headers in files which require them, and remove others
which are not required.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-09-13 12:33:06 +02:00
Thomas Gleixner
d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Flavio Leitner
08010a2160 netfilter: add API to manage NAT helpers.
The API allows a conntrack helper to indicate its corresponding
NAT helper which then can be loaded and reference counted.

Signed-off-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-04-30 14:19:55 +02:00
Florian Westphal
fc3893fd5c netfilter: conntrack: remove empty pernet fini stubs
after moving sysctl handling into single place, the init functions
can't fail anymore and some of the fini functions are empty.

Remove them and change return type to void.
This also simplifies error unwinding in conntrack module init path.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-21 00:51:54 +01:00
Florian Westphal
d912dec124 netfilter: conntrack: merge acct and helper sysctl table with main one
Needless copy&paste, just handle all in one.  Next patch will handle
acct and timestamp, which have similar functions.

Intentionally leaves cruft behind, will be cleaned up in a followup
patch.

The obsolete sysctl pointers in netns_ct struct are left in place and
removed in a single change, as changes to netns trigger rebuild of
almost all files.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-21 00:51:48 +01:00
Li RongQing
285189c78e netfilter: use kvmalloc_array to allocate memory for hashtable
nf_ct_alloc_hashtable is used to allocate memory for conntrack,
NAT bysrc and expectation hashtable. Assuming 64k bucket size,
which means 7th order page allocation, __get_free_pages, called
by nf_ct_alloc_hashtable, will trigger the direct memory reclaim
and stall for a long time, when system has lots of memory stress

so replace combination of __get_free_pages and vzalloc with
kvmalloc_array, which provides a overflow check and a fallback
if no high order memory is available, and do not retry to reclaim
memory, reduce stall

and remove nf_ct_free_hashtable, since it is just a kvfree

Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Wang Li <wangli39@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-08-03 18:37:55 +02:00
Gao Feng
440534d3c5 netfilter: Remove useless param helper of nf_ct_helper_ext_add
The param helper of nf_ct_helper_ext_add is useless now, then remove
it now.

Signed-off-by: Gao Feng <gfree.wind@vip.163.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-07-18 11:26:42 +02:00
Florian Westphal
f957be9d34 netfilter: conntrack: remove ctnetlink callbacks from l3 protocol trackers
handle everything from ctnetlink directly.

After all these years we still only support ipv4 and ipv6, so it
seems reasonable to remove l3 protocol tracker support and instead
handle ipv4/ipv6 from a common, always builtin inet tracker.

Step 1: Get rid of all the l3proto->func() calls.

Start with ctnetlink, then move on to packet-path ones.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-07-16 17:54:58 +02:00
Gao Feng
ad9852af97 netfilter: nf_ct_helper: Fix possible panic after nf_conntrack_helper_unregister
The helper module would be unloaded after nf_conntrack_helper_unregister,
so it may cause a possible panic caused by race.

nf_ct_iterate_destroy(unhelp, me) reset the helper of conntrack as NULL,
but maybe someone has gotten the helper pointer during this period. Then
it would panic, when it accesses the helper and the module was unloaded.

Take an example as following:
CPU0                                                   CPU1
ctnetlink_dump_helpinfo
helper = rcu_dereference(help->helper);
                                                       unhelp
                                                       set helper as NULL
                                                       unload helper module
helper->to_nlattr(skb, ct);

As above, the cpu0 tries to access the helper and its module is unloaded,
then the panic happens.

Signed-off-by: Gao Feng <gfree.wind@vip.163.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-06-18 14:15:12 +02:00
Florian Westphal
ac7b848390 netfilter: expect: add and use nf_ct_expect_iterate helpers
We have several spots that open-code a expect walk, add a helper
that is similar to nf_ct_iterate_destroy/nf_ct_iterate_cleanup.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-31 19:09:38 +02:00
Liping Zhang
ff1acc4964 netfilter: nf_ct_helper: use nf_ct_iterate_destroy to unlink helper objs
When we unlink the helper objects, we will iterate the nf_conntrack_hash,
iterate the unconfirmed list, handle the hash resize situation, etc.

Actually this logic is same as the nf_ct_iterate_destroy, so we can use
it to remove these copy & paste code.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-29 12:46:23 +02:00
Liping Zhang
9338d7b441 netfilter: nfnl_cthelper: reject del request if helper obj is in use
We can still delete the ct helper even if it is in use, this will cause
a use-after-free error. In more detail, I mean:
  # nfct helper add ssdp inet udp
  # iptables -t raw -A OUTPUT -p udp -j CT --helper ssdp
  # nfct helper delete ssdp //--> oops, succeed!
  BUG: unable to handle kernel paging request at 000026ca
  IP: 0x26ca
  [...]
  Call Trace:
   ? ipv4_helper+0x62/0x80 [nf_conntrack_ipv4]
   nf_hook_slow+0x21/0xb0
   ip_output+0xe9/0x100
   ? ip_fragment.constprop.54+0xc0/0xc0
   ip_local_out+0x33/0x40
   ip_send_skb+0x16/0x80
   udp_send_skb+0x84/0x240
   udp_sendmsg+0x35d/0xa50

So add reference count to fix this issue, if ct helper is used by
others, reject the delete request.

Apply this patch:
  # nfct helper delete ssdp
  nfct v1.4.3: netlink error: Device or resource busy

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-15 12:42:29 +02:00
Liping Zhang
d91fc59cd7 netfilter: introduce nf_conntrack_helper_put helper function
And convert module_put invocation to nf_conntrack_helper_put, this is
prepared for the followup patch, which will add a refcnt for cthelper,
so we can reject the deleting request when cthelper is in use.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-15 12:42:29 +02:00
David S. Miller
4d89ac2dd5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter/IPVS/OVS fixes for net

The following patchset contains a rather large batch of Netfilter, IPVS
and OVS fixes for your net tree. This includes fixes for ctnetlink, the
userspace conntrack helper infrastructure, conntrack OVS support,
ebtables DNAT target, several leaks in error path among other. More
specifically, they are:

1) Fix reference count leak in the CT target error path, from Gao Feng.

2) Remove conntrack entry clashing with a matching expectation, patch
   from Jarno Rajahalme.

3) Fix bogus EEXIST when registering two different userspace helpers,
   from Liping Zhang.

4) Don't leak dummy elements in the new bitmap set type in nf_tables,
   from Liping Zhang.

5) Get rid of module autoload from conntrack update path in ctnetlink,
   we don't need autoload at this late stage and it is happening with
   rcu read lock held which is not good. From Liping Zhang.

6) Fix deadlock due to double-acquire of the expect_lock from conntrack
   update path, this fixes a bug that was introduced when the central
   spinlock got removed. Again from Liping Zhang.

7) Safe ct->status update from ctnetlink path, from Liping. The expect_lock
   protection that was selected when the central spinlock was removed was
   not really protecting anything at all.

8) Protect sequence adjustment under ct->lock.

9) Missing socket match with IPv6, from Peter Tirsek.

10) Adjust skb->pkt_type of DNAT'ed frames from ebtables, from
    Linus Luessing.

11) Don't give up on evaluating the expression on new entries added via
    dynset expression in nf_tables, from Liping Zhang.

12) Use skb_checksum() when mangling icmpv6 in IPv6 NAT as this deals
    with non-linear skbuffs.

13) Don't allow IPv6 service in IPVS if no IPv6 support is available,
    from Paolo Abeni.

14) Missing mutex release in error path of xt_find_table_lock(), from
    Dan Carpenter.

15) Update maintainers files, Netfilter section. Add Florian to the
    file, refer to nftables.org and change project status from Supported
    to Maintained.

16) Bail out on mismatching extensions in element updates in nf_tables.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-03 10:11:26 -04:00
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
Florian Westphal
23f671a1b5 netfilter: conntrack: mark extension structs as const
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-26 09:30:22 +02:00
Liping Zhang
66e5a6b18b netfilter: nf_ct_helper: permit cthelpers with different names via nfnetlink
cthelpers added via nfnetlink may have the same tuple, i.e. except for
the l3proto and l4proto, other fields are all zero. So even with the
different names, we will also fail to add them:
  # nfct helper add ssdp inet udp
  # nfct helper add tftp inet udp
  nfct v1.4.3: netlink error: File exists

So in order to avoid unpredictable behaviour, we should:
1. cthelpers can be selected by nft ct helper obj or xt_CT target, so
report error if duplicated { name, l3proto, l4proto } tuple exist.
2. cthelpers can be selected by nf_ct_tuple_src_mask_cmp when
nf_ct_auto_assign_helper is enabled, so also report error if duplicated
{ l3proto, l4proto, src-port } tuple exist.

Also note, if the cthelper is added from userspace, then the src-port will
always be zero, it's invalid for nf_ct_auto_assign_helper, so there's no
need to check the second point listed above.

Fixes: 893e093c78 ("netfilter: nf_ct_helper: bail out on duplicated helpers")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-24 20:05:05 +02:00
Florian Westphal
9f0f3ebeda netfilter: helpers: remove data_len usage for inkernel helpers
No need to track this for inkernel helpers anymore as
NF_CT_HELPER_BUILD_BUG_ON checks do this now.

All inkernel helpers know what kind of structure they
stored in helper->data.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-19 17:55:17 +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
Gao Feng
ec0e3f0111 netfilter: nf_ct_expect: Add nf_ct_remove_expect()
When remove one expect, it needs three statements. And there are
multiple duplicated codes in current code. So add one common function
nf_ct_remove_expect to consolidate this.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-06 18:39:40 +02:00
Gao Feng
92f73221f9 netfilter: expect: Make sure the max_expected limit is effective
Because the type of expecting, the member of nf_conn_help, is u8, it
would overflow after reach U8_MAX(255). So it doesn't work when we
configure the max_expected exceeds 255 with expect policy.

Now add the check for max_expected. Return the -EINVAL when it exceeds
the limit.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-06 18:32:16 +02:00
Jiri Kosina
dfe75ff8ca netfilter: nf_ct_helper: warn when not applying default helper assignment
Commit 3bb398d925 ("netfilter: nf_ct_helper: disable automatic helper
assignment") is causing behavior regressions in firewalls, as traffic
handled by conntrack helpers is now by default not passed through even
though it was before due to missing CT targets (which were not necessary
before this commit).

The default had to be switched off due to security reasons [1] [2] and
therefore should stay the way it is, but let's be friendly to firewall
admins and issue a warning the first time we're in situation where packet
would be likely passed through with the old default but we're likely going
to drop it on the floor now.

Rewrite the code a little bit as suggested by Linus, so that we avoid
spaghettiing the code even more -- namely the whole decision making
process regarding helper selection (either automatic or not) is being
separated, so that the whole logic can be simplified and code (condition)
duplication reduced.

[1] https://cansecwest.com/csw12/conntrack-attack.pdf
[2] https://home.regit.org/netfilter-en/secure-use-of-helpers/

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-06 12:03:35 +01:00
Florian Westphal
6114cc516d netfilter: conntrack: fix CT target for UNSPEC helpers
Thomas reports its not possible to attach the H.245 helper:

iptables -t raw -A PREROUTING -p udp -j CT --helper H.245
iptables: No chain/target/match by that name.
xt_CT: No such helper "H.245"

This is because H.245 registers as NFPROTO_UNSPEC, but the CT target
passes NFPROTO_IPV4/IPV6 to nf_conntrack_helper_try_module_get.

We should treat UNSPEC as wildcard and ignore the l3num instead.

Reported-by: Thomas Woerner <twoerner@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-08 23:53:37 +01:00
Aaron Conole
e2361cb90a netfilter: Remove explicit rcu_read_lock in nf_hook_slow
All of the callers of nf_hook_slow already hold the rcu_read_lock, so this
cleanup removes the recursive call.  This is just a cleanup, as the locking
code gracefully handles this situation.

Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-24 21:29:53 +02:00
Pablo Neira
cf71c03edf netfilter: nf_conntrack: simplify __nf_ct_try_assign_helper() return logic
Instead of several goto's just to return the result, simply return it.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-12 19:54:34 +02:00
Gao Feng
82de0be686 netfilter: Add helper array register/unregister functions
Add nf_ct_helper_init(), nf_conntrack_helpers_register() and
nf_conntrack_helpers_unregister() functions to avoid repetitive
opencoded initialization in helpers.

This patch keeps an id parameter for nf_ct_helper_init() not to break
helper matching by name that has been inconsistently exposed to
userspace through ports, eg. ftp-2121, and through an incremental id,
eg. tftp-1.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-21 02:31:53 +02:00
Liping Zhang
8786a9716d netfilter: nf_ct_helper: unlink helper again when hash resize happen
From: Liping Zhang <liping.zhang@spreadtrum.com>

Similar to ctnl_untimeout, when hash resize happened, we should try
to do unhelp from the 0# bucket again.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-11 11:44:34 +02:00
David S. Miller
ae3e4562e2 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 net-next,
they are:

1) Don't use userspace datatypes in bridge netfilter code, from
   Tobin Harding.

2) Iterate only once over the expectation table when removing the
   helper module, instead of once per-netns, from Florian Westphal.

3) Extra sanitization in xt_hook_ops_alloc() to return error in case
   we ever pass zero hooks, xt_hook_ops_alloc():

4) Handle NFPROTO_INET from the logging core infrastructure, from
   Liping Zhang.

5) Autoload loggers when TRACE target is used from rules, this doesn't
   change the behaviour in case the user already selected nfnetlink_log
   as preferred way to print tracing logs, also from Liping Zhang.

6) Conntrack slabs with SLAB_HWCACHE_ALIGN to allow rearranging fields
   by cache lines, increases the size of entries in 11% per entry.
   From Florian Westphal.

7) Skip zone comparison if CONFIG_NF_CONNTRACK_ZONES=n, from Florian.

8) Remove useless defensive check in nf_logger_find_get() from Shivani
   Bhardwaj.

9) Remove zone extension as place it in the conntrack object, this is
   always include in the hashing and we expect more intensive use of
   zones since containers are in place. Also from Florian Westphal.

10) Owner match now works from any namespace, from Eric Bierdeman.

11) Make sure we only reply with TCP reset to TCP traffic from
    nf_reject_ipv4, patch from Liping Zhang.

12) Introduce --nflog-size to indicate amount of network packet bytes
    that are copied to userspace via log message, from Vishwanath Pai.
    This obsoletes --nflog-range that has never worked, it was designed
    to achieve this but it has never worked.

13) Introduce generic macros for nf_tables object generation masks.

14) Use generation mask in table, chain and set objects in nf_tables.
    This allows fixes interferences with ongoing preparation phase of
    the commit protocol and object listings going on at the same time.
    This update is introduced in three patches, one per object.

15) Check if the object is active in the next generation for element
    deactivation in the rbtree implementation, given that deactivation
    happens from the commit phase path we have to observe the future
    status of the object.

16) Support for deletion of just added elements in the hash set type.

17) Allow to resize hashtable from /proc entry, not only from the
    obscure /sys entry that maps to the module parameter, from Florian
    Westphal.

18) Get rid of NFT_BASECHAIN_DISABLED, this code is not exercised
    anymore since we tear down the ruleset whenever the netdevice
    goes away.

19) Support for matching inverted set lookups, from Arturo Borrero.

20) Simplify the iptables_mangle_hook() by removing a superfluous
    extra branch.

21) Introduce ether_addr_equal_masked() and use it from the netfilter
    codebase, from Joe Perches.

22) Remove references to "Use netfilter MARK value as routing key"
    from the Netfilter Kconfig description given that this toggle
    doesn't exists already for 10 years, from Moritz Sichert.

23) Introduce generic NF_INVF() and use it from the xtables codebase,
    from Joe Perches.

24) Setting logger to NONE via /proc was not working unless explicit
    nul-termination was included in the string. This fixes seems to
    leave the former behaviour there, so we don't break backward.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-06 09:15:15 -07:00
Florian Westphal
436a850dd9 netfilter: helper: avoid extra expectation iterations on unregister
The expectation table is not duplicated per net namespace anymore, so we can move
the expectation table and conntrack table iteration out of the per-net loop.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-06-07 17:26:51 +02:00
David S. Miller
fc14963f24 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for your net tree,
they are:

1) Fix incorrect timestamp in nfnetlink_queue introduced when addressing
   y2038 safe timestamp, from Florian Westphal.

2) Get rid of leftover conntrack definition from the previous merge
   window, oneliner from Florian.

3) Make nf_queue handler pernet to resolve race on dereferencing the
   hook state structure with netns removal, from Eric Biederman.

4) Ensure clean exit on unregistered helper ports, from Taehee Yoo.

5) Restore FLOWI_FLAG_KNOWN_NH in nf_dup_ipv6. This got lost while
   generalizing xt_TEE to add packet duplication support in nf_tables,
   from Paolo Abeni.

6) Insufficient netlink NFTA_SET_TABLE attribute check in
   nf_tables_getset(), from Phil Turnbull.

7) Reject helper registration on duplicated ports via modparams.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-01 17:54:19 -07:00
Pablo Neira Ayuso
893e093c78 netfilter: nf_ct_helper: bail out on duplicated helpers
Don't allow registration of helpers using the same tuple:

	{ l3proto, l4proto, src-port }

We lookup for the helper from the packet path using this tuple through
__nf_ct_helper_find(). Therefore, we have to avoid having two helpers
with the same tuple to ensure predictible behaviour.

Don't compare the helper string names anymore since it is valid to
register two helpers with the same name, but using different tuples.
This is also implicitly fixing up duplicated helper registration via
ports= modparam since the name comparison was defeating the tuple
duplication validation.

Reported-by: Feng Gao <gfree.wind@gmail.com>
Reported-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-31 11:57:18 +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
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
Pablo Neira Ayuso
3bb398d925 netfilter: nf_ct_helper: disable automatic helper assignment
Four years ago we introduced a new sysctl knob to disable automatic
helper assignment in 72110dfaa907 ("netfilter: nf_ct_helper: disable
automatic helper assignment"). This knob kept this behaviour enabled by
default to remain conservative.

This measure was introduced to provide a secure way to configure
iptables and connection tracking helpers through explicit rules.

Give the time we have waited for this, let's turn off this by default
now, worse case users still have a chance to recover the former
behaviour by explicitly enabling this back through sysctl.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-25 15:34:30 +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
stephen hemminger
01cfa0a4ed netfilter: fix spelling errors
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-10-30 17:35:30 +01:00
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
Patrick McHardy
f229f6ce48 netfilter: add my copyright statements
Add copyright statements to all netfilter files which have had significant
changes done by myself in the past.

Some notes:

- nf_conntrack_ecache.c was incorrectly attributed to Rusty and Netfilter
  Core Team when it got split out of nf_conntrack_core.c. The copyrights
  even state a date which lies six years before it was written. It was
  written in 2005 by Harald and myself.

- net/ipv{4,6}/netfilter.c, net/netfitler/nf_queue.c were missing copyright
  statements. I've added the copyright statement from net/netfilter/core.c,
  where this code originated

- for nf_conntrack_proto_tcp.c I've also added Jozsef, since I didn't want
  it to give the wrong impression

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-04-18 20:27:55 +02:00
Gao feng
30e0c6a6be netfilter: nf_log: prepare net namespace support for loggers
This patch adds netns support to nf_log and it prepares netns
support for existing loggers. It is composed of four major
changes.

1) nf_log_register has been split to two functions: nf_log_register
   and nf_log_set. The new nf_log_register is used to globally
   register the nf_logger and nf_log_set is used for enabling
   pernet support from nf_loggers.

   Per netns is not yet complete after this patch, it comes in
   separate follow up patches.

2) Add net as a parameter of nf_log_bind_pf. Per netns is not
   yet complete after this patch, it only allows to bind the
   nf_logger to the protocol family from init_net and it skips
   other cases.

3) Adapt all nf_log_packet callers to pass netns as parameter.
   After this patch, this function only works for init_net.

4) Make the sysctl net/netfilter/nf_log pernet.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-04-05 20:12:54 +02:00
David S. Miller
43b18db8a2 Merge branch 'master' of git://1984.lsi.us.es/nf
Pablo Neira Ayuso says:

====================
The following patchset contains Netfilter fixes for your net tree,
they are:

* Don't generate audit log message if audit is not enabled, from Gao Feng.

* Fix logging formatting for packets dropped by helpers, by Joe Perches.

* Fix a compilation warning in nfnetlink if CONFIG_PROVE_RCU is not set,
  from Paul Bolle.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-07 15:20:02 -05:00
Joe Perches
f9caed59f8 netfilter: nf_ct_helper: Fix logging for dropped packets
Update nf_ct_helper_log to emit args along with the format.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-03-02 22:44:45 +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
Pablo Neira Ayuso
b20ab9cc63 netfilter: nf_ct_helper: better logging for dropped packets
Connection tracking helpers have to drop packets under exceptional
situations. Currently, the user gets the following logging message
in case that happens:

	nf_ct_%s: dropping packet ...

However, depending on the helper, there are different reasons why a
packet can be dropped.

This patch modifies the existing code to provide more specific
error message in the scope of each helper to help users to debug
the reason why the packet has been dropped, ie:

	nf_ct_%s: dropping packet: reason ...

Thanks to Joe Perches for many formatting suggestions.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-02-19 02:48:05 +01:00
Florian Westphal
6e2f0aa8cf netfilter: nf_ct_helper: don't discard helper if it is actually the same
commit (32f5376 netfilter: nf_ct_helper: disable automatic helper
re-assignment of different type) broke transparent proxy scenarios.

For example, initial helper lookup might yield "ftp" (dport 21),
while re-lookup after REDIRECT yields "ftp-2121".

This causes the autoassign code to toss the ftp helper, even
though these are just different instances of the same helper.

Change the test to check for the helper function address instead
of the helper address, as suggested by Pablo.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@gnumonks.org>
2013-02-12 23:20:46 +01:00
Gao feng
5e615b2200 netfilter: nf_ct_helper: move initialization out of pernet_operations
Move the global initial codes to the module_init/exit context.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-23 12:56:13 +01:00
Eric W. Biederman
464dc801c7 net: Don't export sysctls to unprivileged users
In preparation for supporting the creation of network namespaces
by unprivileged users, modify all of the per net sysctl exports
and refuse to allow them to unprivileged users.

This makes it safe for unprivileged users in general to access
per net sysctls, and allows sysctls to be exported to unprivileged
users on an individual basis as they are deemed safe.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-18 20:30:55 -05:00