When register_pernet_subsys() fails, nf_nat_bysource
should be freed just like when nf_ct_extend_register()
fails.
Fixes: 1cd472bf03 ("netfilter: nf_nat: add nat hook register functions to nf_nat")
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
In 9fb9cbb108 ("[NETFILTER]: Add nf_conntrack subsystem.") the new
generic nf_conntrack was introduced, and it came to supersede the old
ip_conntrack.
This change updates (some) of the obsolete comments referring to old
file/function names of the ip_conntrack mechanism, as well as removes a
few self-referencing comments that we shouldn't maintain anymore.
I did not update any comments referring to historical actions (e.g,
comments like "this file was derived from ..." were left untouched, even
if the referenced file is no longer here).
Signed-off-by: Yonatan Goldschmidt <yon.goldschmidt@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
We currently have two levels of strict validation:
1) liberal (default)
- undefined (type >= max) & NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
- garbage at end of message accepted
2) strict (opt-in)
- NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
Split out parsing strictness into four different options:
* TRAILING - check that there's no trailing data after parsing
attributes (in message or nested)
* MAXTYPE - reject attrs > max known type
* UNSPEC - reject attributes with NLA_UNSPEC policy entries
* STRICT_ATTRS - strictly validate attribute size
The default for future things should be *everything*.
The current *_strict() is a combination of TRAILING and MAXTYPE,
and is renamed to _deprecated_strict().
The current regular parsing has none of this, and is renamed to
*_parse_deprecated().
Additionally it allows us to selectively set one of the new flags
even on old policies. Notably, the UNSPEC flag could be useful in
this case, since it can be arranged (by filling in the policy) to
not be an incompatible userspace ABI change, but would then going
forward prevent forgetting attribute entries. Similar can apply
to the POLICY flag.
We end up with the following renames:
* nla_parse -> nla_parse_deprecated
* nla_parse_strict -> nla_parse_deprecated_strict
* nlmsg_parse -> nlmsg_parse_deprecated
* nlmsg_parse_strict -> nlmsg_parse_deprecated_strict
* nla_parse_nested -> nla_parse_nested_deprecated
* nla_validate_nested -> nla_validate_nested_deprecated
Using spatch, of course:
@@
expression TB, MAX, HEAD, LEN, POL, EXT;
@@
-nla_parse(TB, MAX, HEAD, LEN, POL, EXT)
+nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT)
@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT)
@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
@@
expression TB, MAX, NLA, POL, EXT;
@@
-nla_parse_nested(TB, MAX, NLA, POL, EXT)
+nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT)
@@
expression START, MAX, POL, EXT;
@@
-nla_validate_nested(START, MAX, POL, EXT)
+nla_validate_nested_deprecated(START, MAX, POL, EXT)
@@
expression NLH, HDRLEN, MAX, POL, EXT;
@@
-nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT)
+nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT)
For this patch, don't actually add the strict, non-renamed versions
yet so that it breaks compile if I get it wrong.
Also, while at it, make nla_validate and nla_parse go down to a
common __nla_validate_parse() function to avoid code duplication.
Ultimately, this allows us to have very strict validation for every
new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the
next patch, while existing things will continue to work as is.
In effect then, this adds fully strict validation for any new command.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sven Auhagen reported that a 2nd ping request will fail if 'fully-random'
mode is used.
Reason is that if no proto information is given, min/max are both 0,
so we set the icmp id to 0 instead of chosing a random value between
0 and 65535.
Update test case as well to catch this, without fix this yields:
[..]
ERROR: cannot ping ns1 from ns2 with ip masquerade fully-random (attempt 2)
ERROR: cannot ping ns1 from ns2 with ipv6 masquerade fully-random (attempt 2)
... becaus 2nd ping clashes with existing 'id 0' icmp conntrack and gets
dropped.
Fixes: 203f2e7820 ("netfilter: nat: remove l4proto->unique_tuple")
Reported-by: Sven Auhagen <sven.auhagen@voleatech.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We need minimal support from the nat core for this, as we do not
want to register additional base hooks.
When an inet hook is registered, interally register ipv4 and ipv6
hooks for them and unregister those when inet hooks are removed.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Empty case is fine and does not switch fall-through
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The l3proto name is gone, its header file is the last trace.
While at it, also remove nf_nat_core.h, its very small and all users
include nf_nat.h too.
before:
text data bss dec hex filename
22948 1612 4136 28696 7018 nf_nat.ko
after removal of l3proto register/unregister functions:
text data bss dec hex filename
22196 1516 4136 27848 6cc8 nf_nat.ko
checkpatch complains about overly long lines, but line breaks
do not make things more readable and the line length gets smaller
here, not larger.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
before:
text data bss dec hex filename
16566 1576 4136 22278 5706 nf_nat.ko
3598 844 0 4442 115a nf_nat_ipv6.ko
3187 844 0 4031 fbf nf_nat_ipv4.ko
after:
text data bss dec hex filename
22948 1612 4136 28696 7018 nf_nat.ko
... with ipv4/v6 nat now provided directly via nf_nat.ko.
Also changes:
ret = nf_nat_ipv4_fn(priv, skb, state);
if (ret != NF_DROP && ret != NF_STOLEN &&
into
if (ret != NF_ACCEPT)
return ret;
everywhere.
The nat hooks never should return anything other than
ACCEPT or DROP (and the latter only in rare error cases).
The original code uses multi-line ANDing including assignment-in-if:
if (ret != NF_DROP && ret != NF_STOLEN &&
!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) &&
(ct = nf_ct_get(skb, &ctinfo)) != NULL) {
I removed this while moving, breaking those in separate conditionals
and moving the assignments into extra lines.
checkpatch still generates some warnings:
1. Overly long lines (of moved code).
Breaking them is even more ugly. so I kept this as-is.
2. use of extern function declarations in a .c file.
This is necessary evil, we must call
nf_nat_l3proto_register() from the nat core now.
All l3proto related functions are removed later in this series,
those prototypes are then removed as well.
v2: keep empty nf_nat_ipv6_csum_update stub for CONFIG_IPV6=n case.
v3: remove IS_ENABLED(NF_NAT_IPV4/6) tests, NF_NAT_IPVx toggles
are removed here.
v4: also get rid of the assignments in conditionals.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
None of these functions calls any external functions, moving them allows
to avoid both the indirection and a need to export these symbols.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Not used since 203f2e7820 ("netfilter: nat: remove l4proto->unique_tuple")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
after removal of the packet and invert function pointers, several
places do not need to lookup the l4proto structure anymore.
Remove those lookups.
The function nf_ct_invert_tuplepr becomes redundant, replace
it with nf_ct_invert_tuple everywhere.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for net-next:
1) Support for destination MAC in ipset, from Stefano Brivio.
2) Disallow all-zeroes MAC address in ipset, also from Stefano.
3) Add IPSET_CMD_GET_BYNAME and IPSET_CMD_GET_BYINDEX commands,
introduce protocol version number 7, from Jozsef Kadlecsik.
A follow up patch to fix ip_set_byindex() is also included
in this batch.
4) Honor CTA_MARK_MASK from ctnetlink, from Andreas Jaggi.
5) Statify nf_flow_table_iterate(), from Taehee Yoo.
6) Use nf_flow_table_iterate() to simplify garbage collection in
nf_flow_table logic, also from Taehee Yoo.
7) Don't use _bh variants of call_rcu(), rcu_barrier() and
synchronize_rcu_bh() in Netfilter, from Paul E. McKenney.
8) Remove NFC_* cache definition from the old caching
infrastructure.
9) Remove layer 4 port rover in NAT helpers, use random port
instead, from Florian Westphal.
10) Use strscpy() in ipset, from Qian Cai.
11) Remove NF_NAT_RANGE_PROTO_RANDOM_FULLY branch now that
random port is allocated by default, from Xiaozhou Liu.
12) Ignore NF_NAT_RANGE_PROTO_RANDOM too, from Florian Westphal.
13) Limit port allocation selection routine in NAT to avoid
softlockup splats when most ports are in use, from Florian.
14) Remove unused parameters in nf_ct_l4proto_unregister_sysctl()
from Yafang Shao.
15) Direct call to nf_nat_l4proto_unique_tuple() instead of
indirection, from Florian Westphal.
16) Several patches to remove all layer 4 NAT indirections,
remove nf_nat_l4proto struct, from Florian Westphal.
17) Fix RTP/RTCP source port translation when SNAT is in place,
from Alin Nastac.
18) Selective rule dump per chain, from Phil Sutter.
19) Revisit CLUSTERIP target, this includes a deadlock fix from
netns path, sleep in atomic, remove bogus WARN_ON_ONCE()
and disallow mismatching IP address and MAC address.
Patchset from Taehee Yoo.
20) Update UDP timeout to stream after 2 seconds, from Florian.
21) Shrink UDP established timeout to 120 seconds like TCP timewait.
22) Sysctl knobs to set GRE timeouts, from Yafang Shao.
23) Move seq_print_acct() to conntrack core file, from Florian.
24) Add enum for conntrack sysctl knobs, also from Florian.
25) Place nf_conntrack_acct, nf_conntrack_helper, nf_conntrack_events
and nf_conntrack_timestamp knobs in the core, from Florian Westphal.
As a side effect, shrink netns_ct structure by removing obsolete
sysctl anchors, also from Florian.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This removes the (now empty) nf_nat_l4proto struct, all its instances
and all the no longer needed runtime (un)register functionality.
nf_nat_need_gre() can be axed as well: the module that calls it (to
load the no-longer-existing nat_gre module) also calls other nat core
functions. GRE nat is now always available if kernel is built with it.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
all protocols did set this to nf_nat_l4proto_nlattr_to_range, so
just call it directly.
The important difference is that we'll now also call it for
protocols that we don't support (i.e., nf_nat_proto_unknown did
not provide .nlattr_to_range).
However, there should be no harm, even icmp provided this callback.
If we don't implement a specific l4nat for this, nothing would make
use of this information, so adding a big switch/case construct listing
all supported l4protocols seems a bit pointless.
This change leaves a single function pointer in the l4proto struct.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
With exception of icmp, all of the l4 nat protocols set this to
nf_nat_l4proto_in_range.
Get rid of this and just check the l4proto in the caller.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
No need for indirections here, we only support ipv4 and ipv6
and the called functions are very small.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
fold remaining users (icmp, icmpv6, gre) into nf_nat_l4proto_unique_tuple.
The static-save of old incarnation of resolved key in gre and icmp is
removed as well, just use the prandom based offset like the others.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
almost all l4proto->unique_tuple implementations just call this helper,
so make ->unique_tuple() optional and call its helper directly if the
l4proto doesn't override it.
This is an intermediate step to get rid of ->unique_tuple completely.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
This unifies ipv4 and ipv6 protocol trackers and removes the l3proto
abstraction.
This gets rid of all l3proto indirect calls and the need to do
a lookup on the function to call for l3 demux.
It increases module size by only a small amount (12kbyte), so this reduces
size because nf_conntrack.ko is useless without either nf_conntrack_ipv4
or nf_conntrack_ipv6 module.
before:
text data bss dec hex filename
7357 1088 0 8445 20fd nf_conntrack_ipv4.ko
7405 1084 4 8493 212d nf_conntrack_ipv6.ko
72614 13689 236 86539 1520b nf_conntrack.ko
19K nf_conntrack_ipv4.ko
19K nf_conntrack_ipv6.ko
179K nf_conntrack.ko
after:
text data bss dec hex filename
79277 13937 236 93450 16d0a nf_conntrack.ko
191K nf_conntrack.ko
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Netfilter assumes that if the socket is present in the skb, then
it can be used because that reference is cleaned up while the skb
is crossing netns.
We want to change that to preserve the socket reference in a future
patch, so this is a preparation updating netfilter to check if the
socket netns matches before use it.
Signed-off-by: Flavio Leitner <fbl@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes the following sparse warning:
net/netfilter/nf_nat_core.c:1039:20: warning:
symbol 'nat_hook' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In nfqueue, two consecutive skbuffs may race to create the conntrack
entry. Hence, the one that loses the race gets dropped due to clash in
the insertion into the hashes from the nf_conntrack_confirm() path.
This patch adds a new nf_conntrack_update() function which searches for
possible clashes and resolve them. NAT mangling for the packet losing
race is corrected by using the conntrack information that won race.
In order to avoid direct module dependencies with conntrack and NAT, the
nf_ct_hook and nf_nat_hook structures are used for this purpose.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently the packet rewrite and instantiation of nat NULL bindings
happens from the protocol specific nat backend.
Invocation occurs either via ip(6)table_nat or the nf_tables nat chain type.
Invocation looks like this (simplified):
NF_HOOK()
|
`---iptable_nat
|
`---> nf_nat_l3proto_ipv4 -> nf_nat_packet
|
new packet? pass skb though iptables nat chain
|
`---> iptable_nat: ipt_do_table
In nft case, this looks the same (nft_chain_nat_ipv4 instead of
iptable_nat).
This is a problem for two reasons:
1. Can't use iptables nat and nf_tables nat at the same time,
as the first user adds a nat binding (nf_nat_l3proto_ipv4 adds a
NULL binding if do_table() did not find a matching nat rule so we
can detect post-nat tuple collisions).
2. If you use e.g. nft_masq, snat, redir, etc. uses must also register
an empty base chain so that the nat core gets called fro NF_HOOK()
to do the reverse translation, which is neither obvious nor user
friendly.
After this change, the base hook gets registered not from iptable_nat or
nftables nat hooks, but from the l3 nat core.
iptables/nft nat base hooks get registered with the nat core instead:
NF_HOOK()
|
`---> nf_nat_l3proto_ipv4 -> nf_nat_packet
|
new packet? pass skb through iptables/nftables nat chains
|
+-> iptables_nat: ipt_do_table
+-> nft nat chain x
`-> nft nat chain y
The nat core deals with null bindings and reverse translation.
When no mapping exists, it calls the registered nat lookup hooks until
one creates a new mapping.
If both iptables and nftables nat hooks exist, the first matching
one is used (i.e., higher priority wins).
Also, nft users do not need to create empty nat hooks anymore,
nat core always registers the base hooks that take care of reverse/reply
translation.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This adds the infrastructure to register nat hooks with the nat core
instead of the netfilter core.
nat hooks are used to configure nat bindings. Such hooks are registered
from ip(6)table_nat or by the nftables core when a nat chain is added.
After next patch, nat hooks will be registered with nf_nat instead of
netfilter core. This allows to use many nat lookup functions at the
same time while doing the real packet rewrite (nat transformation) in
one place.
This change doesn't convert the intended users yet to ease review.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Copy-pasted, both l3 helpers almost use same code here.
Split out the common part into an 'inet' helper.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This is a patch proposal to support shifted ranges in portmaps. (i.e. tcp/udp
incoming port 5000-5100 on WAN redirected to LAN 192.168.1.5:2000-2100)
Currently DNAT only works for single port or identical port ranges. (i.e.
ports 5000-5100 on WAN interface redirected to a LAN host while original
destination port is not altered) When different port ranges are configured,
either 'random' mode should be used, or else all incoming connections are
mapped onto the first port in the redirect range. (in described example
WAN:5000-5100 will all be mapped to 192.168.1.5:2000)
This patch introduces a new mode indicated by flag NF_NAT_RANGE_PROTO_OFFSET
which uses a base port value to calculate an offset with the destination port
present in the incoming stream. That offset is then applied as index within the
redirect port range (index modulo rangewidth to handle range overflow).
In described example the base port would be 5000. An incoming stream with
destination port 5004 would result in an offset value 4 which means that the
NAT'ed stream will be using destination port 2004.
Other possibilities include deterministic mapping of larger or multiple ranges
to a smaller range : WAN:5000-5999 -> LAN:5000-5099 (maps WAN port 5*xx to port
51xx)
This patch does not change any current behavior. It just adds new NAT proto
range functionality which must be selected via the specific flag when intended
to use.
A patch for iptables (libipt_DNAT.c + libip6t_DNAT.c) will also be proposed
which makes this functionality immediately available.
Signed-off-by: Thierry Du Tre <thierry@dtsystems.be>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Using pr_<loglevel>() is more concise than printk(KERN_<LOGLEVEL>).
This patch:
* Replace printks having a log level with the appropriate
pr_*() macros.
* Define pr_fmt() to include relevant name.
* Remove redundant prefixes from pr_*() calls.
* Indent the code where possible.
* Remove the useless output messages.
* Remove periods from messages.
Signed-off-by: Arushi Singhal <arushisinghal19971997@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We can use a single statement for this.
While at it, fixup the comment -- we don't have pernet table/ops
anymore, the function is only called from module exit path.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If no spinlock debugging options (CONFIG_GENERIC_LOCKBREAK,
CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_LOCK_ALLOC) are enabled on a UP
platform (e.g. m68k defconfig), arch_spinlock_t is an empty struct,
hence using ARRAY_SIZE(nf_nat_locks) causes a division by zero:
net/netfilter/nf_nat_core.c: In function ‘nf_nat_setup_info’:
net/netfilter/nf_nat_core.c:432: warning: division by zero
net/netfilter/nf_nat_core.c: In function ‘__nf_nat_cleanup_conntrack’:
net/netfilter/nf_nat_core.c:535: warning: division by zero
net/netfilter/nf_nat_core.c:537: warning: division by zero
net/netfilter/nf_nat_core.c: In function ‘nf_nat_init’:
net/netfilter/nf_nat_core.c:810: warning: division by zero
net/netfilter/nf_nat_core.c:811: warning: division by zero
net/netfilter/nf_nat_core.c:824: warning: division by zero
Fix this by using the CONNTRACK_LOCKS definition instead.
Suggested-by: Florian Westphal <fw@strlen.de>
Fixes: 8073e960a0 ("netfilter: nat: use keyed locks")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
no need to serialize on a single lock, we can partition the table and
add/delete in parallel to different slots.
This restores one of the advantages that got lost with the rhlist
revert.
Cc: Ivan Babrou <ibobrik@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This reverts commit 870190a9ec.
It was not a good idea. The custom hash table was a much better
fit for this purpose.
A fast lookup is not essential, in fact for most cases there is no lookup
at all because original tuple is not taken and can be used as-is.
What needs to be fast is insertion and deletion.
rhlist removal however requires a rhlist walk.
We can have thousands of entries in such a list if source port/addresses
are reused for multiple flows, if this happens removal requests are so
expensive that deletions of a few thousand flows can take several
seconds(!).
The advantages that we got from rhashtable are:
1) table auto-sizing
2) multiple locks
1) would be nice to have, but it is not essential as we have at
most one lookup per new flow, so even a million flows in the bysource
table are not a problem compared to current deletion cost.
2) is easy to add to custom hash table.
I tried to add hlist_node to rhlist to speed up rhltable_remove but this
isn't doable without changing semantics. rhltable_remove_fast will
check that the to-be-deleted object is part of the table and that
requires a list walk that we want to avoid.
Furthermore, using hlist_node increases size of struct rhlist_head, which
in turn increases nf_conn size.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196821
Reported-by: Ivan Babrou <ibobrik@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
It seems preferrable to limp along if we have a conflicting mapping,
its certainly better than a BUG().
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Commit 4440a2ab3b ("netfilter: synproxy: Check oom when adding synproxy
and seqadj ct extensions") wanted to drop the packet when it fails to add
seqadj ext due to no memory by checking if nfct_seqadj_ext_add returns
NULL.
But that nfct_seqadj_ext_add returns NULL can also happen when seqadj ext
already exists in a nf_conn. It will cause that userspace protocol doesn't
work when both dnat and snat are configured.
Li Shuang found this issue in the case:
Topo:
ftp client router ftp server
10.167.131.2 <-> 10.167.131.254 10.167.141.254 <-> 10.167.141.1
Rules:
# iptables -t nat -A PREROUTING -i eth1 -p tcp -m tcp --dport 21 -j \
DNAT --to-destination 10.167.141.1
# iptables -t nat -A POSTROUTING -o eth2 -p tcp -m tcp --dport 21 -j \
SNAT --to-source 10.167.141.254
In router, when both dnat and snat are added, nf_nat_setup_info will be
called twice. The packet can be dropped at the 2nd time for DNAT due to
seqadj ext is already added at the 1st time for SNAT.
This patch is to fix it by checking for seqadj ext existence before adding
it, so that the packet will not be dropped if seqadj ext already exists.
Note that as Florian mentioned, as a long term, we should review ext_add()
behaviour, it's better to return a pointer to the existing ext instead.
Fixes: 4440a2ab3b ("netfilter: synproxy: Check oom when adding synproxy and seqadj ct extensions")
Reported-by: Li Shuang <shuali@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When doing initial conversion to rhashtable I replaced the bucket
walk with a single rhashtable_lookup_fast().
When moving to rhlist I failed to properly walk the list of identical
tuples, but that is what is needed for this to work correctly.
The table contains the original tuples, so the reply tuples are all
distinct.
We currently decide that mapping is (not) in range only based on the
first entry, but in case its not we need to try the reply tuple of the
next entry until we either find an in-range mapping or we checked
all the entries.
This bug makes nat core attempt collision resolution while it might be
able to use the mapping as-is.
Fixes: 870190a9ec ("netfilter: nat: convert nat bysrc hash to rhashtable")
Reported-by: Jaco Kroon <jaco@uls.co.za>
Tested-by: Jaco Kroon <jaco@uls.co.za>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for your net-next
tree. This batch contains connection tracking updates for the cleanup
iteration path, patches from Florian Westphal:
X) Skip unconfirmed conntracks in nf_ct_iterate_cleanup_net(), just set
dying bit to let the CPU release them.
X) Add nf_ct_iterate_destroy() to be used on module removal, to kill
conntrack from all namespace.
X) Restart iteration on hashtable resizing, since both may occur at
the same time.
X) Use the new nf_ct_iterate_destroy() to remove conntrack with NAT
mapping on module removal.
X) Use nf_ct_iterate_destroy() to remove conntrack entries helper
module removal, from Liping Zhang.
X) Use nf_ct_iterate_cleanup_net() to remove the timeout extension
if user requests this, also from Liping.
X) Add net_ns_barrier() and use it from FTP helper, so make sure
no concurrent namespace removal happens at the same time while
the helper module is being removed.
X) Use NFPROTO_MAX in layer 3 conntrack protocol array, to reduce
module size. Same thing in nf_tables.
Updates for the nf_tables infrastructure:
X) Prepare usage of the extended ACK reporting infrastructure for
nf_tables.
X) Remove unnecessary forward declaration in nf_tables hash set.
X) Skip set size estimation if number of element is not specified.
X) Changes to accomodate a (faster) unresizable hash set implementation,
for anonymous sets and dynamic size fixed sets with no timeouts.
X) Faster lookup function for unresizable hash table for 2 and 4
bytes key.
And, finally, a bunch of asorted small updates and cleanups:
X) Do not hold reference to netdev from ipt_CLUSTER, instead subscribe
to device events and look up for index from the packet path, this
is fixing an issue that is present since the very beginning, patch
from Xin Long.
X) Use nf_register_net_hook() in ipt_CLUSTER, from Florian Westphal.
X) Use ebt_invalid_target() whenever possible in the ebtables tree,
from Gao Feng.
X) Calm down compilation warning in nf_dup infrastructure, patch from
stephen hemminger.
X) Statify functions in nftables rt expression, also from stephen.
X) Update Makefile to use canonical method to specify nf_tables-objs.
From Jike Song.
X) Use nf_conntrack_helpers_register() in amanda and H323.
X) Space cleanup for ctnetlink, from linzhang.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
We don't need pernetns cleanup anymore. If the netns is being
destroyed, conntrack netns exit will kill all entries in this namespace,
and neither conntrack hash table nor bysource hash are per namespace.
For the rmmod case, we have to make sure we remove all entries from the
nat bysource table, so call the new nf_ct_iterate_destroy in module exit
path.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There are several places where we needlesly call nf_ct_iterate_cleanup,
we should instead iterate the full table at module unload time.
This is a leftover from back when the conntrack table got duplicated
per net namespace.
So rename nf_ct_iterate_cleanup to nf_ct_iterate_cleanup_net.
A later patch will then add a non-net variant.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We need to clear the IPS_SRC_NAT_DONE_BIT to indicate that the ct has
been removed from nat_bysource table. But unfortunately, we use the
non-atomic bit operation: "ct->status &= ~IPS_NAT_DONE_MASK". So
there's a race condition that we may clear the _DYING_BIT set by
another CPU unexpectedly.
Since we don't care about the IPS_DST_NAT_DONE_BIT, so just using
clear_bit to clear the IPS_SRC_NAT_DONE_BIT is enough.
Also note, this is the last user which use the non-atomic bit operation
to update the confirmed ct->status.
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Florian Westphal