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156 Commits (dbec982c695aa32e73532869f4cd15346cf46afe)

Author SHA1 Message Date
Pablo Neira Ayuso 90964016e5 netfilter: nf_conntrack: add IPS_OFFLOAD status bit
This new bit tells us that the conntrack entry is owned by the flow
table offload infrastructure.

 # cat /proc/net/nf_conntrack
 ipv4     2 tcp      6 src=10.141.10.2 dst=147.75.205.195 sport=36392 dport=443 src=147.75.205.195 dst=192.168.2.195 sport=443 dport=36392 [OFFLOAD] mark=0 zone=0 use=2

Note the [OFFLOAD] tag in the listing.

The timer of such conntrack entries look like stopped from userspace.
In practise, to make sure the conntrack entry does not go away, the
conntrack timer is periodically set to an arbitrary large value that
gets refreshed on every iteration from the garbage collector, so it
never expires- and they display no internal state in the case of TCP
flows. This allows us to save a bitcheck from the packet path via
nf_ct_is_expired().

Conntrack entries that have been offloaded to the flow table
infrastructure cannot be deleted/flushed via ctnetlink. The flow table
infrastructure is also responsible for releasing this conntrack entry.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:11:05 +01:00
Florian Westphal 2c9e8637ea netfilter: conntrack: timeouts can be const
Nowadays this is just the default template that is used when setting up
the net namespace, so nothing writes to these locations.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:02 +01:00
Florian Westphal 9dae47aba0 netfilter: conntrack: l4 protocol trackers can be const
previous patches removed all writes to these structs so we can
now mark them as const.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:00:54 +01:00
Florian Westphal 3921584674 netfilter: conntrack: remove nlattr_size pointer from l4proto trackers
similar to previous commit, but instead compute this at compile time
and turn nlattr_size into an u16.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 16:47:14 +01:00
Florian Westphal fbcd253d24 netfilter: conntrack: lower timeout to RETRANS seconds if window is 0
When zero window is announced we can get into a situation where
connection stays around forever:

1. One side announces zero window.
2. Other side closes.

In this case, no FIN is sent (stuck in send queue).

Unless other side opens the window up again conntrack
stays in ESTABLISHED state for a very long time.

Lets alleviate this by lowering the timeout to RETRANS (5 minutes),
the other end should be sending zero window probes to keep the
connection established as long as a socket still exists.

Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-11-20 13:30:24 +01:00
Florian Westphal 5caaed151a netfilter: conntrack: don't cache nlattr_tuple_size result in nla_size
We currently call ->nlattr_tuple_size() once at register time and
cache result in l4proto->nla_size.

nla_size is the only member that is written to, avoiding this would
allow to make l4proto trackers const.

We can use ->nlattr_tuple_size() at run time, and cache result in
the individual trackers instead.

This is an intermediate step, next patch removes nlattr_size()
callback and computes size at compile time, then removes nla_size.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-11-06 16:48:38 +01:00
Florian Westphal eb6fad5a4a netfilter: conntrack: remove pf argument from l4 packet functions
not needed/used anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-10-24 18:01:49 +02:00
Florian Westphal 3d0b527bc9 netfilter: conntrack: add and use nf_ct_l4proto_log_invalid
We currently pass down the l4 protocol to the conntrack ->packet()
function, but the only user of this is the debug info decision.

Same information can be derived from struct nf_conn.
Add a wrapper for the previous patch that extracs the information
from nf_conn and passes it to nf_l4proto_log_invalid().

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-10-24 18:01:49 +02:00
Florian Westphal c4f3db1595 netfilter: conntrack: add and use nf_l4proto_log_invalid
We currently pass down the l4 protocol to the conntrack ->packet()
function, but the only user of this is the debug info decision.

Same information can be derived from struct nf_conn.
As a first step, add and use a new log function for this, similar to
nf_ct_helper_log().

Add __cold annotation -- invalid packets should be infrequent so
gcc can consider all call paths that lead to such a function as
unlikely.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-10-24 18:01:49 +02:00
Florian Westphal d1c1e39de8 netfilter: remove unused hooknum arg from packet functions
tested with allmodconfig build.

Signed-off-by: Florian Westphal <fw@strlen.de>
2017-09-04 13:25:18 +02:00
Florian Westphal ea48cc83cf netfilter: conntrack: print_conntrack only needed if CONFIG_NF_CONNTRACK_PROCFS
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24 18:52:33 +02:00
Florian Westphal 91950833dd netfilter: conntrack: place print_tuple in procfs part
CONFIG_NF_CONNTRACK_PROCFS is deprecated, no need to use a function
pointer in the trackers for this. Place the printf formatting in
the one place that uses it.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24 18:52:32 +02:00
Florian Westphal 09ec82f5af netfilter: conntrack: remove protocol name from l4proto struct
no need to waste storage for something that is only needed
in one place and can be deduced from protocol number.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24 18:52:32 +02:00
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
Gao Feng 122868b378 netfilter: tcp: Use TCP_MAX_WSCALE instead of literal 14
The window scale may be enlarged from 14 to 15 according to the itef
draft https://tools.ietf.org/html/draft-nishida-tcpm-maxwin-03.

Use the macro TCP_MAX_WSCALE to support it easily with TCP stack in
the future.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-19 17:55:17 +02:00
Florian Westphal c6dd940b1f netfilter: allow early drop of assured conntracks
If insertion of a new conntrack fails because the table is full, the kernel
searches the next buckets of the hash slot where the new connection
was supposed to be inserted at for an entry that hasn't seen traffic
in reply direction (non-assured), if it finds one, that entry is
is dropped and the new connection entry is allocated.

Allow the conntrack gc worker to also remove *assured* conntracks if
resources are low.

Do this by querying the l4 tracker, e.g. tcp connections are now dropped
if they are no longer established (e.g. in finwait).

This could be refined further, e.g. by adding 'soft' established timeout
(i.e., a timeout that is only used once we get close to resource
exhaustion).

Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-19 17:55:17 +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
Florian Westphal 11df4b760f netfilter: conntrack: no need to pass ctinfo to error handler
It is never accessed for reading and the only places that write to it
are the icmp(6) handlers, which also set skb->nfct (and skb->nfctinfo).

The conntrack core specifically checks for attached skb->nfct after
->error() invocation and returns early in this case.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-02 14:31:51 +01:00
Pablo Neira Ayuso adf0516845 netfilter: remove ip_conntrack* sysctl compat code
This backward compatibility has been around for more than ten years,
since Yasuyuki Kozakai introduced IPv6 in conntrack. These days, we have
alternate /proc/net/nf_conntrack* entries, the ctnetlink interface and
the conntrack utility got adopted by many people in the user community
according to what I observed on the netfilter user mailing list.

So let's get rid of this.

Note that nf_conntrack_htable_size and unsigned int nf_conntrack_max do
not need to be exported as symbol anymore.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-13 13:27:13 +02:00
Gao Feng e5e693ab49 netfilter: conntrack: Only need first 4 bytes to get l4proto ports
We only need first 4 bytes instead of 8 bytes to get the ports of
tcp/udp/dccp/sctp/udplite in their pkt_to_tuple function.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-12 00:41:08 +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
Florian Westphal a163f2cb39 netfilter: conntrack: don't acquire lock during seq_printf
read access doesn't need any lock here.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-19 20:26:25 +02:00
Jozsef Kadlecsik 644c7e48cb netfilter: nf_conntrack_tcp: Fix stack out of bounds when parsing TCP options
Baozeng Ding reported a KASAN stack out of bounds issue - it uncovered that
the TCP option parsing routines in netfilter TCP connection tracking could
read one byte out of the buffer of the TCP options.  Therefore in the patch
we check that the available data length is large enough to parse both TCP
option code and size.

Reported-by: Baozeng Ding <sploving1@gmail.com>
Tested-by: Baozeng Ding <sploving1@gmail.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-07 18:42:37 +02:00
Eric W. Biederman a31f1adc09 netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple
As gre does not have the srckey in the packet gre_pkt_to_tuple
needs to perform a lookup in it's per network namespace tables.

Pass in the proper network namespace to all pkt_to_tuple
implementations to ensure gre (and any similar protocols) can get this
right.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 22:00:04 +02:00
Jesper Dangaard Brouer b3cad287d1 conntrack: RFC5961 challenge ACK confuse conntrack LAST-ACK transition
In compliance with RFC5961, the network stack send challenge ACK in
response to spurious SYN packets, since commit 0c228e833c ("tcp:
Restore RFC5961-compliant behavior for SYN packets").

This pose a problem for netfilter conntrack in state LAST_ACK, because
this challenge ACK is (falsely) seen as ACKing last FIN, causing a
false state transition (into TIME_WAIT).

The challenge ACK is hard to distinguish from real last ACK.  Thus,
solution introduce a flag that tracks the potential for seeing a
challenge ACK, in case a SYN packet is let through and current state
is LAST_ACK.

When conntrack transition LAST_ACK to TIME_WAIT happens, this flag is
used for determining if we are expecting a challenge ACK.

Scapy based reproducer script avail here:
 https://github.com/netoptimizer/network-testing/blob/master/scapy/tcp_hacks_3WHS_LAST_ACK.py

Fixes: 0c228e833c ("tcp: Restore RFC5961-compliant behavior for SYN packets")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-05-15 20:50:56 +02:00
Al Viro ba00410b81 Merge branch 'iov_iter' into for-next 2014-12-08 20:39:29 -05:00
Joe Perches 824f1fbee7 netfilter: Convert print_tuple functions to return void
Since adding a new function to seq_file (seq_has_overflowed())
there isn't any value for functions called from seq_show to
return anything.   Remove the int returns of the various
print_tuple/<foo>_print_tuple functions.

Link: http://lkml.kernel.org/p/f2e8cf8df433a197daa62cbaf124c900c708edc7.1412031505.git.joe@perches.com

Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: netfilter-devel@vger.kernel.org
Cc: coreteam@netfilter.org
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-05 14:10:33 -05:00
Steven Rostedt (Red Hat) 37246a5837 netfilter: Remove return values for print_conntrack callbacks
The seq_printf() and friends are having their return values removed.
The print_conntrack() returns the result of seq_printf(), which is
meaningless when seq_printf() returns void. Might as well remove the
return values of print_conntrack() as well.

Link: http://lkml.kernel.org/r/20141029220107.465008329@goodmis.org
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: netfilter-devel@vger.kernel.org
Cc: coreteam@netfilter.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-05 14:09:47 -05:00
Marcelo Leitner e37ad9fd63 netfilter: nf_conntrack: allow server to become a client in TW handling
When a port that was used to listen for inbound connections gets closed
and reused for outgoing connections (like rsh ends up doing for stderr
flow), current we may reject the SYN/ACK packet for the new connection
because tcp_conntracks states forbirds a port to become a client while
there is still a TIME_WAIT entry in there for it.

As TCP may expire the TIME_WAIT socket in 60s and conntrack's timeout
for it is 120s, there is a ~60s window that the application can end up
opening a port that conntrack will end up blocking.

This patch fixes this by simply allowing such state transition: if we
see a SYN, in TIME_WAIT state, on REPLY direction, move it to sSS. Note
that the rest of the code already handles this situation, more
specificly in tcp_packet(), first switch clause.

Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-10-22 14:12:50 +02:00
Patrick McHardy 48b1de4c11 netfilter: add SYNPROXY core/target
Add a SYNPROXY for netfilter. The code is split into two parts, the synproxy
core with common functions and an address family specific target.

The SYNPROXY receives the connection request from the client, responds with
a SYN/ACK containing a SYN cookie and announcing a zero window and checks
whether the final ACK from the client contains a valid cookie.

It then establishes a connection to the original destination and, if
successful, sends a window update to the client with the window size
announced by the server.

Support for timestamps, SACK, window scaling and MSS options can be
statically configured as target parameters if the features of the server
are known. If timestamps are used, the timestamp value sent back to
the client in the SYN/ACK will be different from the real timestamp of
the server. In order to now break PAWS, the timestamps are translated in
the direction server->client.

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 00:27:54 +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
David S. Miller 89d5e23210 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Conflicts:
	net/netfilter/nf_conntrack_proto_tcp.c

The conflict had to do with overlapping changes dealing with
fixing the use of an "s32" to hold the value returned by
NAT_OFFSET().

Pablo Neira Ayuso says:

====================
The following batch contains Netfilter/IPVS updates for your net-next tree.
More specifically, they are:

* Trivial typo fix in xt_addrtype, from Phil Oester.

* Remove net_ratelimit in the conntrack logging for consistency with other
  logging subsystem, from Patrick McHardy.

* Remove unneeded includes from the recently added xt_connlabel support, from
  Florian Westphal.

* Allow to update conntracks via nfqueue, don't need NFQA_CFG_F_CONNTRACK for
  this, from Florian Westphal.

* Remove tproxy core, now that we have socket early demux, from Florian
  Westphal.

* A couple of patches to refactor conntrack event reporting to save a good
  bunch of lines, from Florian Westphal.

* Fix missing locking in NAT sequence adjustment, it did not manifested in
  any known bug so far, from Patrick McHardy.

* Change sequence number adjustment variable to 32 bits, to delay the
  possible early overflow in long standing connections, also from Patrick.

* Comestic cleanups for IPVS, from Dragos Foianu.

* Fix possible null dereference in IPVS in the SH scheduler, from Daniel
  Borkmann.

* Allow to attach conntrack expectations via nfqueue. Before this patch, you
  had to use ctnetlink instead, thus, we save the conntrack lookup.

* Export xt_rpfilter and xt_HMARK header files, from Nicolas Dichtel.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-20 13:30:54 -07:00
Yuchung Cheng 356d7d88e0 netfilter: nf_conntrack: fix tcp_in_window for Fast Open
Currently the conntrack checks if the ending sequence of a packet
falls within the observed receive window. However it does so even
if it has not observe any packet from the remote yet and uses an
uninitialized receive window (td_maxwin).

If a connection uses Fast Open to send a SYN-data packet which is
dropped afterward in the network. The subsequent SYNs retransmits
will all fail this check and be discarded, leading to a connection
timeout. This is because the SYN retransmit does not contain data
payload so

end == initial sequence number (isn) + 1
sender->td_end == isn + syn_data_len
receiver->td_maxwin == 0

The fix is to only apply this check after td_maxwin is initialized.

Reported-by: Michael Chan <mcfchan@stanford.edu>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-08-10 18:36:22 +02:00
Patrick McHardy 2d89c68ac7 netfilter: nf_nat: change sequence number adjustments to 32 bits
Using 16 bits is too small, when many adjustments happen the offsets might
overflow and break the connection.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-07-31 19:54:51 +02:00
Florian Westphal 6547a22187 netfilter: nf_conntrack: avoid large timeout for mid-stream pickup
When loose tracking is enabled (default), non-syn packets cause
creation of new conntracks in established state with default timeout for
established state (5 days).  This causes the table to fill up with UNREPLIED
when the 'new ack' packet happened to be the last-ack of a previous,
already timed-out connection.

Consider:

A 192.168.x.52792 > 10.184.y.80: F, 426:426(0) ack 9237 win 255
B 10.184.y.80 > 192.168.x.52792: ., ack 427 win 123
<61 second pause>
C 10.184.y.80 > 192.168.x.52792: F, 9237:9237(0) ack 427 win 123
D 192.168.x.52792 > 10.184.y.80: ., ack 9238 win 255

B moves conntrack to CLOSE_WAIT and will kill it after 60 second timeout,
C is ignored (FIN set), but last packet (D) causes new ct with 5-days timeout.

Use UNACK timeout (5 minutes) instead to get rid of these entries sooner
when in ESTABLISHED state without having seen traffic in both directions.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-06-20 11:20:13 +02:00
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
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
David S. Miller b48b63a1f6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/netfilter/nfnetlink_log.c
	net/netfilter/xt_LOG.c

Rather easy conflict resolution, the 'net' tree had bug fixes to make
sure we checked if a socket is a time-wait one or not and elide the
logging code if so.

Whereas on the 'net-next' side we are calculating the UID and GID from
the creds using different interfaces due to the user namespace changes
from Eric Biederman.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-15 11:43:53 -04:00
Jozsef Kadlecsik 4a70bbfaef netfilter: Validate the sequence number of dataless ACK packets as well
We spare nothing by not validating the sequence number of dataless
ACK packets and enabling it makes harder off-path attacks.

See: "Reflection scan: an Off-Path Attack on TCP" by Jan Wrobel,
http://arxiv.org/abs/1201.2074

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-09-09 22:13:49 +02:00
Jozsef Kadlecsik 64f509ce71 netfilter: Mark SYN/ACK packets as invalid from original direction
Clients should not send such packets. By accepting them, we open
up a hole by wich ephemeral ports can be discovered in an off-path
attack.

See: "Reflection scan: an Off-Path Attack on TCP" by Jan Wrobel,
http://arxiv.org/abs/1201.2074

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-09-09 22:13:30 +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 be0593c678 netfilter: nf_ct_tcp: missing per-net support for cttimeout
This patch adds missing per-net support for the cttimeout
infrastructure to TCP.

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

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

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
2012-07-04 19:37:22 +02:00
Gao feng efa758fe2c netfilter: nf_ct_tcp: merge tcpv[4,6]_net_init into tcp_net_init
Merge tcpv4_net_init and tcpv6_net_init into tcp_net_init to
remove redundant code now that we have the u_int16_t proto
parameter.

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

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 19:05:05 +02:00
Gao feng f1caad2745 netfilter: nf_conntrack: prepare l4proto->init_net cleanup
l4proto->init contain quite redundant code. We can simplify this
by adding a new parameter l3proto.

This patch prepares that code simplification.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27 18:31:14 +02:00
Pablo Neira Ayuso 352e04b911 netfilter: nf_ct_tcp, udp: fix compilation with sysctl disabled
This patch fixes the compilation of the TCP and UDP trackers with sysctl
compilation disabled:

net/netfilter/nf_conntrack_proto_udp.c: In function ‘udp_init_net_data’:
net/netfilter/nf_conntrack_proto_udp.c:279:13: error: ‘struct nf_proto_net’ has no member named
 ‘user’
net/netfilter/nf_conntrack_proto_tcp.c:1606:9: error: ‘struct nf_proto_net’ has no member named
 ‘user’
net/netfilter/nf_conntrack_proto_tcp.c:1643:9: error: ‘struct nf_proto_net’ has no member named
 ‘user’

Reported-by: Fengguang Wu <wfg@linux.intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-11 15:22:46 -07:00
Gao feng 8264deb818 netfilter: nf_conntrack: add namespace support for cttimeout
This patch adds namespace support for cttimeout.

Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-07 14:58:41 +02:00
Pablo Neira Ayuso e76d0af5e4 netfilter: nf_conntrack: remove now unused sysctl for nf_conntrack_l[3|4]proto
Since the sysctl data for l[3|4]proto now resides in pernet nf_proto_net.
We can now remove this unused fields from struct nf_contrack_l[3,4]proto.

Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-07 14:58:41 +02:00
Gao feng d2ba1fde42 netfilter: nf_ct_tcp: add namespace support
This patch adds namespace support for TCP protocol tracker.

Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-07 14:58:39 +02:00