Currently DNS resolvers that send both A and AAAA queries from same source port
can trigger stream mode prematurely, which results in non-early-evictable conntrack entry
for three minutes, even though DNS requests are done in a few milliseconds.
Add a two second grace period where we continue to use the ordinary
30-second default timeout. Its enough for DNS request/response traffic,
even if two request/reply packets are involved.
ASSURED is still set, else conntrack (and thus a possible
NAT mapping ...) gets zapped too in case conntrack table runs full.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If same destination IP address config is already existing, that config is
just used. MAC address also should be same.
However, there is no MAC address checking routine.
So that MAC address checking routine is added.
test commands:
%iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \
-j CLUSTERIP --new --hashmode sourceip \
--clustermac 01:00:5e:00:00:20 --total-nodes 2 --local-node 1
%iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \
-j CLUSTERIP --new --hashmode sourceip \
--clustermac 01:00:5e:00:00:21 --total-nodes 2 --local-node 1
After this patch, above commands are disallowed.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If just a table name was given, nf_tables_dump_rules() continued over
the list of tables even after a match was found. The simple fix is to
exit the loop if it reached the bottom and ctx->table was not NULL.
When iterating over the table's chains, the same problem as above
existed. But worse than that, if a chain name was given the hash table
wasn't used to find the corresponding chain. Fix this by introducing a
helper function iterating over a chain's rules (and taking care of the
cb->args handling), then introduce a shortcut to it if a chain name was
given.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Each media stream negotiation between 2 SIP peers will trigger creation
of 4 different expectations (2 RTP and 2 RTCP):
- INVITE will create expectations for the media packets sent by the
called peer
- reply to the INVITE will create expectations for media packets sent
by the caller
The dport used by these expectations usually match the ones selected
by the SIP peers, but they might get translated due to conflicts with
another expectation. When such event occur, it is important to do
this translation in both directions, dport translation on the receiving
path and sport translation on the sending path.
This commit fixes the sport translation when the peer requiring it is
also the one that starts the media stream. In this scenario, first media
stream packet is forwarded from LAN to WAN and will rely on
nf_nat_sip_expected() to do the necessary sport translation. However, the
expectation matched by this packet does not contain the necessary information
for doing SNAT, this data being stored in the paired expectation created by
the sender's SIP message (INVITE or reply to it).
Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
This removes the last l4proto indirection, the two callers, the l3proto
packet mangling helpers for ipv4 and ipv6, now call the
nf_nat_l4proto_manip_pkt() helper.
nf_nat_proto_{dccp,tcp,sctp,gre,icmp,icmpv6} are left behind, even though
they contain no functionality anymore to not clutter this patch.
Next patch will remove the empty files and the nf_nat_l4proto
struct.
nf_nat_proto_udp.c is renamed to nf_nat_proto.c, as it now contains the
other nat manip functionality as well, not just udp and udplite.
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>
Historically this was net_random() based, and was then converted to
a hash based algorithm (private boot seed + hash of endpoint addresses)
due to concerns of leaking net_random() bits.
RANDOM_FULLY mode was added later to avoid problems with hash
based mode (see commit 34ce324019,
"netfilter: nf_nat: add full port randomization support" for details).
Just make prandom_u32() the default search starting point and get rid of
->secure_port() altogether.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In case almost or all available ports are taken, clash resolution can
take a very long time, resulting in soft lockup.
This can happen when many to-be-natted hosts connect to same
destination:port (e.g. a proxy) and all connections pass the same SNAT.
Pick a random offset in the acceptable range, then try ever smaller
number of adjacent port numbers, until either the limit is reached or a
useable port was found. This results in at most 248 attempts
(128 + 64 + 32 + 16 + 8, i.e. 4 restarts with new search offset)
instead of 64000+,
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since a pseudo-random starting point is used in finding a port in
the default case, that 'else if' branch above is no longer a necessity.
So remove it to simplify code.
Signed-off-by: Xiaozhou Liu <liuxiaozhou@bytedance.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
To make overflows as obvious as possible and to prevent code from blithely
proceeding with a truncated string. This also has a side-effect to fix a
compilation warning when using GCC 8.2.1.
net/netfilter/ipset/ip_set_core.c: In function 'ip_set_sockfn_get':
net/netfilter/ipset/ip_set_core.c:2027:3: warning: 'strncpy' writing 32 bytes into a region of size 2 overflows the destination [-Wstringop-overflow=]
Signed-off-by: Qian Cai <cai@gmx.us>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
New function added by "Introduction of new commands and protocol
version 7" is not working, since we return skb2 to user
Signed-off-by: Victorien Molle <victorien.molle@wifirst.fr>
Signed-off-by: Florent Fourcot <florent.fourcot@wifirst.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This is a leftover from days where single-cpu systems were common:
Store last port used to resolve a clash to use it as a starting point when
the next conflict needs to be resolved.
When we have parallel attempt to connect to same address:port pair,
its likely that both cores end up computing the same "available" port,
as both use same starting port, and newly used ports won't become
visible to other cores until the conntrack gets confirmed later.
One of the cores then has to drop the packet at insertion time because
the chosen new tuple turns out to be in use after all.
Lets simplify this: remove port rover and use a pseudo-random starting
point.
Note that this doesn't make netfilter default to 'fully random' mode;
the 'rover' was only used if NAT could not reuse source port as-is.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
These are very very (for long time unused) caching infrastructure
definition, remove then. They have nothing to do with the NFC subsystem.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Now that call_rcu()'s callback is not invoked until after bh-disable
regions of code have completed (in addition to explicitly marked
RCU read-side critical sections), call_rcu() can be used in place
of call_rcu_bh(). Similarly, rcu_barrier() can be used in place of
rcu_barrier_bh() and synchronize_rcu() in place of synchronize_rcu_bh().
This commit therefore makes these changes.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_flow_offload_gc_step() and nf_flow_table_iterate() are very similar.
so that many duplicate code can be removed.
After this patch, nf_flow_offload_gc_step() is simple callback function of
nf_flow_table_iterate() like nf_flow_table_do_cleanup().
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_flow_table_iterate() is local function, make it static.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
