We have no explicit signal when a UDP stream has terminated, peers just
stop sending.
For suspected stream connections a timeout of two minutes is sane to keep
NAT mapping alive a while longer.
It matches tcp conntracks 'timewait' default timeout value.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
l4 protocols are demuxed by l3num, l4num pair.
However, almost all l4 trackers are l3 agnostic.
Only exceptions are:
- gre, icmp (ipv4 only)
- icmpv6 (ipv6 only)
This commit gets rid of the l3 mapping, l4 trackers can now be looked up
by their IPPROTO_XXX value alone, which gets rid of the additional l3
indirection.
For icmp, ipcmp6 and gre, add a check on state->pf and
return -NF_ACCEPT in case we're asked to track e.g. icmpv6-in-ipv4,
this seems more fitting than using the generic tracker.
Additionally we can kill the 2nd l4proto definitions that were needed
for v4/v6 split -- they are now the same so we can use single l4proto
struct for each protocol, rather than two.
The EXPORT_SYMBOLs can be removed as all these object files are
part of nf_conntrack with no external references.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Its unused, next patch will remove l4proto->l3proto number to simplify
l4 protocol demuxer lookup.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Only two protocols need the ->error() function: icmp and icmpv6.
This is because icmp error mssages might be RELATED to an existing
connection (e.g. PMTUD, port unreachable and the like), and their
->error() handlers do this.
The error callback is already optional, so remove it for
udp and call them from ->packet() instead.
As the error() callback can call checksum functions that write to
skb->csum*, the const qualifier has to be removed as well.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
->new() gets invoked after ->error() and before ->packet() if
a conntrack lookup has found no result for the tuple.
We can fold it into ->packet() -- the packet() implementations
can check if the conntrack is confirmed (new) or not
(already in hash).
If its unconfirmed, the conntrack isn't in the hash yet so current
skb created a new conntrack entry.
Only relevant side effect -- if packet() doesn't return NF_ACCEPT
but -NF_ACCEPT (or drop), while the conntrack was just created,
then the newly allocated conntrack is freed right away, rather than not
created in the first place.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_hook_state contains all the hook meta-information: netns, protocol family,
hook location, and so on.
Instead of only passing selected information, pass a pointer to entire
structure.
This will allow to merge the error and the packet handlers and remove
the ->new() function in followup patches.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Now that cttimeout support for nft_ct is in place, these should depend
on CONFIG_NF_CONNTRACK_TIMEOUT otherwise we can crash when dumping the
policy if this option is not enabled.
[ 71.600121] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
[...]
[ 71.600141] CPU: 3 PID: 7612 Comm: nft Not tainted 4.18.0+ #246
[...]
[ 71.600188] Call Trace:
[ 71.600201] ? nft_ct_timeout_obj_dump+0xc6/0xf0 [nft_ct]
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Not needed, we can have the l4trackers fetch it themselvs.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Handle common protocols (udp, tcp, ..), in the core and only
do the call if needed by the l4proto tracker.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Handle the common cases (tcp, udp, etc). in the core and only
do the indirect call for the protocols that need it (GRE for instance).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
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>
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>
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>
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>
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>
udplite was copied from udp, they are virtually 100% identical.
This adds udplite tracker to udp instead, removes udplite module,
and then makes the udplite tracker builtin.
udplite will then simply re-use udp timeout settings.
It makes little sense to add separate sysctls, nowadays we have
fine-grained timeout policy support via the CT target.
old:
text data bss dec hex filename
1633 672 0 2305 901 nf_conntrack_proto_udp.o
1756 672 0 2428 97c nf_conntrack_proto_udplite.o
69526 17937 268 87731 156b3 nf_conntrack.ko
new:
text data bss dec hex filename
2442 1184 0 3626 e2a nf_conntrack_proto_udp.o
68565 17721 268 86554 1521a nf_conntrack.ko
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
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>
This patch introduces nf_ct_resolve_clash() to resolve race condition on
conntrack insertions.
This is particularly a problem for connection-less protocols such as
UDP, with no initial handshake. Two or more packets may race to insert
the entry resulting in packet drops.
Another problematic scenario are packets enqueued to userspace via
NFQUEUE after the raw table, that make it easier to trigger this
race.
To resolve this, the idea is to reset the conntrack entry to the one
that won race. Packet and bytes counters are also merged.
The 'insert_failed' stats still accounts for this situation, after
this patch, the drop counter is bumped whenever we drop packets, so we
can watch for unresolved clashes.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
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>
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>
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>
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>
Merge udpv4_net_init and udpv6_net_init into udp_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>
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>
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>
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>
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>
This patch adds namespace support for UDP 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>
These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the infrastructure to add fine timeout tuning
over nfnetlink. Now you can use the NFNL_SUBSYS_CTNETLINK_TIMEOUT
subsystem to create/delete/dump timeout objects that contain some
specific timeout policy for one flow.
The follow up patches will allow you attach timeout policy object
to conntrack via the CT target and the conntrack extension
infrastructure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch defines a new interface for l4 protocol trackers:
unsigned int *(*get_timeouts)(struct net *net);
that is used to return the array of unsigned int that contains
the timeouts that will be applied for this flow. This is passed
to the l4proto->new(...) and l4proto->packet(...) functions to
specify the timeout policy.
This interface allows per-net global timeout configuration
(although only DCCP supports this by now) and it will allow
custom custom timeout configuration by means of follow-up
patches.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use IS_ENABLED(CONFIG_FOO)
instead of defined(CONFIG_FOO) || defined (CONFIG_FOO_MODULE)
Signed-off-by: Igor Maravić <igorm@etf.rs>
Signed-off-by: David S. Miller <davem@davemloft.net>
The error handlers might need the template to get the conntrack zone
introduced in the next patches to perform a conntrack lookup.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Split up the IPCT_STATUS event into an IPCT_REPLY event, which is generated
when the IPS_SEEN_REPLY bit is set, and an IPCT_ASSURED event, which is
generated when the IPS_ASSURED bit is set.
In combination with a following patch to support selective event delivery,
this can be used for "sparse" conntrack replication: start replicating the
conntrack entry after it reached the ASSURED state and that way it's SYN-flood
resistant.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Now that sys_sysctl is a compatiblity wrapper around /proc/sys
all sysctl strategy routines, and all ctl_name and strategy
entries in the sysctl tables are unused, and can be
revmoed.
In addition neigh_sysctl_register has been modified to no longer
take a strategy argument and it's callers have been modified not
to pass one.
Cc: "David Miller" <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
I want to compile out proc_* and sysctl_* handlers totally and
stub them to NULL depending on config options, however usage of &
will prevent this, since taking adress of NULL pointer will break
compilation.
So, drop & in front of every ->proc_handler and every ->strategy
handler, it was never needed in fact.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is cleaner, we already know conntrack to which event is relevant.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>