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Using a private template is problematic:
1. We can't assign both a zone and a timeout policy
(zone assigns a conntrack template, so we hit problem 1)
2. Using a template needs to take care of ct refcount, else we'll
eventually free the private template due to ->use underflow.
This patch reworks template policy to instead work with existing conntrack.
As long as such conntrack has not yet been placed into the hash table
(unconfirmed) we can still add the timeout extension.
The only caveat is that we now need to update/correct ct->timeout to
reflect the initial/new state, otherwise the conntrack entry retains the
default 'new' timeout.
Side effect of this change is that setting the policy must
now occur from chains that are evaluated *after* the conntrack lookup
has taken place.
No released kernel contains the timeout policy feature yet, so this change
should be ok.
Changes since v2:
- don't handle 'ct is confirmed case'
- after previous patch, no need to special-case tcp/dccp/sctp timeout
anymore
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We must register nfnetlink ops last, as that exposes nf_tables to
userspace. Without this, we could theoretically get nfnetlink request
before net->nft state has been initialized.
Fixes: 99633ab29b ("netfilter: nf_tables: complete net namespace support")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The timeout policy is currently embedded into the nfnetlink_cttimeout
object, move the policy into an independent object. This allows us to
reuse part of the existing conntrack timeout extension from nf_tables
without adding dependencies with the nfnetlink_cttimeout object layout.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
As, ctnl_untimeout is required by nft_ct, so move ctnl_timeout from
nfnetlink_cttimeout to nf_conntrack_timeout and rename as nf_ct_timeout.
Signed-off-by: Harsha Sharma <harshasharmaiitr@gmail.com>
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>
Currently nft uses inlined variants for common operations
such as 'ip saddr 1.2.3.4' instead of an indirect call.
Also handle meta get operations and lookups without indirect call,
both are builtin.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter/IPVS updates for net-next
The following patchset contains Netfilter/IPVS updates for your net-next
tree:
1) No need to set ttl from reject action for the bridge family, from
Taehee Yoo.
2) Use a fixed timeout for flow that are passed up from the flowtable
to conntrack, from Florian Westphal.
3) More preparation patches for tproxy support for nf_tables, from Mate
Eckl.
4) Remove unnecessary indirection in core IPv6 checksum function, from
Florian Westphal.
5) Use nf_ct_get_tuplepr() from openvswitch, instead of opencoding it.
From Florian Westphal.
6) socket match now selects socket infrastructure, instead of depending
on it. From Mate Eckl.
7) Patch series to simplify conntrack tuple building/parsing from packet
path and ctnetlink, from Florian Westphal.
8) Fetch timeout policy from protocol helpers, instead of doing it from
core, from Florian Westphal.
9) Merge IPv4 and IPv6 protocol trackers into conntrack core, from
Florian Westphal.
10) Depend on CONFIG_NF_TABLES_IPV6 and CONFIG_IP6_NF_IPTABLES
respectively, instead of IPV6. Patch from Mate Eckl.
11) Add specific function for garbage collection in conncount,
from Yi-Hung Wei.
12) Catch number of elements in the connlimit list, from Yi-Hung Wei.
13) Move locking to nf_conncount, from Yi-Hung Wei.
14) Series of patches to add lockless tree traversal in nf_conncount,
from Yi-Hung Wei.
15) Resolve clash in matching conntracks when race happens, from
Martynas Pumputis.
16) If connection entry times out, remove template entry from the
ip_vs_conn_tab table to improve behaviour under flood, from
Julian Anastasov.
17) Remove useless parameter from nf_ct_helper_ext_add(), from Gao feng.
18) Call abort from 2-phase commit protocol before requesting modules,
make sure this is done under the mutex, from Florian Westphal.
19) Grab module reference when starting transaction, also from Florian.
20) Dynamically allocate expression info array for pre-parsing, from
Florian.
21) Add per netns mutex for nf_tables, from Florian Westphal.
22) A couple of patches to simplify and refactor nf_osf code to prepare
for nft_osf support.
23) Break evaluation on missing socket, from Mate Eckl.
24) Allow to match socket mark from nft_socket, from Mate Eckl.
25) Remove dependency on nf_defrag_ipv6, now that IPv6 tracker is
built-in into nf_conntrack. From Florian Westphal.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
no need to store the name in separate area.
Furthermore, it uses kmalloc but not kfree and most accesses seem to treat
it as char[IFNAMSIZ] not char *.
Remove this and use dev->name instead.
In case event zeroed dev, just omit the name in the dump.
Fixes: d92191aa84 ("netfilter: nf_tables: cache device name in flowtable object")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The param helper of nf_ct_helper_ext_add is useless now, then remove
it now.
Signed-off-by: Gao Feng <gfree.wind@vip.163.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch is originally from Florian Westphal.
This patch does the following 3 main tasks.
1) Add list lock to 'struct nf_conncount_list' so that we can
alter the lists containing the individual connections without holding the
main tree lock. It would be useful when we only need to add/remove to/from
a list without allocate/remove a node in the tree. With this change, we
update nft_connlimit accordingly since we longer need to maintain
a list lock in nft_connlimit now.
2) Use RCU for the initial tree search to improve tree look up performance.
3) Add a garbage collection worker. This worker is schedule when there
are excessive tree node that needed to be recycled.
Moreover,the rbnode reclaim logic is moved from search tree to insert tree
to avoid race condition.
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch is originally from Florian Westphal.
This patch does the following three tasks.
It applies the same early exit technique for nf_conncount_lookup().
Since now we keep the number of connections in 'struct nf_conncount_list',
we no longer need to return the count in nf_conncount_lookup().
Moreover, we expose the garbage collection function nf_conncount_gc_list()
for nft_connlimit.
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Original patch is from Florian Westphal.
This patch switches from hlist to plain list to store the list of
connections with the same filtering key in nf_conncount. With the
plain list, we can insert new connections at the tail, so over time
the beginning of list holds long-running connections and those are
expired, while the newly creates ones are at the end.
Later on, we could probably move checked ones to the end of the list,
so the next run has higher chance to reclaim stale entries in the front.
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
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>
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 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>
Handle it in the core instead.
ipv6_skip_exthdr() is built-in even if ipv6 is a module, i.e. this
doesn't create an ipv6 dependency.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Its simpler to just handle it directly in nf_ct_invert_tuple().
Also gets rid of need to pass l3proto pointer to resolve_conntrack().
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
handle everything from ctnetlink directly.
After all these years we still only support ipv4 and ipv6, so it
seems reasonable to remove l3 protocol tracker support and instead
handle ipv4/ipv6 from a common, always builtin inet tracker.
Step 1: Get rid of all the l3proto->func() calls.
Start with ctnetlink, then move on to packet-path ones.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
These versions deal with the l3proto/l4proto details internally.
It removes only caller of nf_ct_get_tuple, so make it static.
After this, l3proto->get_l4proto() can be removed in a followup patch.
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This function is also necessary to implement nft tproxy support
Fixes: 45ca4e0cf2 ("netfilter: Libify xt_TPROXY")
Signed-off-by: Máté Eckl <ecklm94@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch disallows rbtree with single elements, which is causing
problems with the recent timeout support. Before this patch, you
could opt out individual set representations per module, which is
just adding extra complexity.
Fixes: 8d8540c4f5e0("netfilter: nft_set_rbtree: add timeout support")
Reported-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch fixes a silent out-of-bound read possibility that was present
because of the misuse of this function.
Mostly it was called with a struct udphdr *hp which had only the udphdr
part linearized by the skb_header_pointer, however
nf_tproxy_get_sock_v{4,6} uses it as a tcphdr pointer, so some reads for
tcp specific attributes may be invalid.
Fixes: a583636a83 ("inet: refactor inet[6]_lookup functions to take skb")
Signed-off-by: Máté Eckl <ecklm94@gmail.com>
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>
Due to the use of rhashtables in net namespaces,
rhashtable.h is included in lots of the kernel,
so a small changes can required a large recompilation.
This makes development painful.
This patch splits out rhashtable-types.h which just includes
the major type declarations, and does not include (non-trivial)
inline code. rhashtable.h is no longer included by anything
in the include/ directory.
Common include files only include rhashtable-types.h so a large
recompilation is only triggered when that changes.
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, we use check_hlist() for garbage colleciton. However, we
use the ‘zone’ from the counted entry to query the existence of
existing entries in the hlist. This could be wrong when they are in
different zones, and this patch fixes this issue.
Fixes: e59ea3df3f ("netfilter: xt_connlimit: honor conntrack zone if available")
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter/IPVS fixes for net
The following patchset contains Netfilter/IPVS fixes for your net tree:
1) Reject non-null terminated helper names from xt_CT, from Gao Feng.
2) Fix KASAN splat due to out-of-bound access from commit phase, from
Alexey Kodanev.
3) Missing conntrack hook registration on IPVS FTP helper, from Julian
Anastasov.
4) Incorrect skbuff allocation size in bridge nft_reject, from Taehee Yoo.
5) Fix inverted check on packet xmit to non-local addresses, also from
Julian.
6) Fix ebtables alignment compat problems, from Alin Nastac.
7) Hook mask checks are not correct in xt_set, from Serhey Popovych.
8) Fix timeout listing of element in ipsets, from Jozsef.
9) Cap maximum timeout value in ipset, also from Jozsef.
10) Don't allow family option for hash:mac sets, from Florent Fourcot.
11) Restrict ebtables to work with NFPROTO_BRIDGE targets only, this
Florian.
12) Another bug reported by KASAN in the rbtree set backend, from
Taehee Yoo.
13) Missing __IPS_MAX_BIT update doesn't include IPS_OFFLOAD_BIT.
From Gao Feng.
14) Missing initialization of match/target in ebtables, from Florian
Westphal.
15) Remove useless nft_dup.h file in include path, from C. Labbe.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
include/net/netfilter/nft_dup.h was introduced in d877f07112 ("netfilter: nf_tables: add nft_dup expression")
but was never user since this date.
Furthermore, the only struct in this file is unused elsewhere.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If there is a significant amount of chains list search is too slow, so
add an rhlist table for this.
This speeds up ruleset loading: for every new rule we have to check if
the name already exists in current generation.
We need to be able to cope with duplicate chain names in case a transaction
drops the nfnl mutex (for request_module) and the abort of this old
transaction is still pending.
The list is kept -- we need a way to iterate chains even if hash resize is
in progress without missing an entry.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Before this patch, cloned expressions are released via ->destroy. This
is a problem for the new connlimit expression since the ->destroy path
drop a reference on the conntrack modules and it unregisters hooks. The
new ->destroy_clone provides context that this expression is being
released from the packet path, so it is mirroring ->clone(), where
neither module reference is dropped nor hooks need to be unregistered -
because this done from the control plane path from the ->init() path.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use garbage collector to schedule removal of elements based of feedback
from expression that this element comes with. Therefore, the garbage
collector is not guided by timeout expirations in this new mode.
The new connlimit expression sets on the NFT_EXPR_GC flag to enable this
behaviour, the dynset expression needs to explicitly enable the garbage
collector via set->ops->gc_init call.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft_set_elem_destroy() can be called from call_rcu context. Annotate
netns and table in set object so we can populate the context object.
Moreover, pass context object to nf_tables_set_elem_destroy() from the
commit phase, since it is already available from there.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch provides an interface to maintain the list of connections and
the lookup function to obtain the number of connections in the list.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The extracted functions will likely be usefull to implement tproxy
support in nf_tables.
Extrancted functions:
- nf_tproxy_sk_is_transparent
- nf_tproxy_laddr4
- nf_tproxy_handle_time_wait4
- nf_tproxy_get_sock_v4
- nf_tproxy_laddr6
- nf_tproxy_handle_time_wait6
- nf_tproxy_get_sock_v6
(nf_)tproxy_handle_time_wait6 also needed some refactor as its current
implementation was xtables-specific.
Signed-off-by: Máté Eckl <ecklm94@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There is a function in include/net/netfilter/nf_socket.h to decide if a
socket has IP(V6)_TRANSPARENT socket option set or not. However this
does the same as inet_sk_transparent() in include/net/tcp.h
include/net/tcp.h:1733
/* This helper checks if socket has IP_TRANSPARENT set */
static inline bool inet_sk_transparent(const struct sock *sk)
{
switch (sk->sk_state) {
case TCP_TIME_WAIT:
return inet_twsk(sk)->tw_transparent;
case TCP_NEW_SYN_RECV:
return inet_rsk(inet_reqsk(sk))->no_srccheck;
}
return inet_sk(sk)->transparent;
}
tproxy_sk_is_transparent has also been refactored to use this function
instead of reimplementing it.
Signed-off-by: Máté Eckl <ecklm94@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The following ruleset:
add table ip filter
add chain ip filter input { type filter hook input priority 4; }
add chain ip filter ap
add rule ip filter input jump ap
add rule ip filter ap masquerade
results in a panic, because the masquerade extension should be rejected
from the filter chain. The existing validation is missing a chain
dependency check when the rule is added to the non-base chain.
This patch fixes the problem by walking down the rules from the
basechains, searching for either immediate or lookup expressions, then
jumping to non-base chains and again walking down the rules to perform
the expression validation, so we make sure the full ruleset graph is
validated. This is done only once from the commit phase, in case of
problem, we abort the transaction and perform fine grain validation for
error reporting. This patch requires 003087911a ("netfilter:
nfnetlink: allow commit to fail") to achieve this behaviour.
This patch also adds a cleanup callback to nfnl batch interface to reset
the validate state from the exit path.
As a result of this patch, nf_tables_check_loops() doesn't use
->validate to check for loops, instead it just checks for immediate
expressions.
Reported-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
synchronize_rcu() is expensive.
The commit phase currently enforces an unconditional
synchronize_rcu() after incrementing the generation counter.
This is to make sure that a packet always sees a consistent chain, either
nft_do_chain is still using old generation (it will skip the newly added
rules), or the new one (it will skip old ones that might still be linked
into the list).
We could just remove the synchronize_rcu(), it would not cause a crash but
it could cause us to evaluate a rule that was removed and new rule for the
same packet, instead of either-or.
To resolve this, add rule pointer array holding two generations, the
current one and the future generation.
In commit phase, allocate the rule blob and populate it with the rules that
will be active in the new generation.
Then, make this rule blob public, replacing the old generation pointer.
Then the generation counter can be incremented.
nft_do_chain() will either continue to use the current generation
(in case loop was invoked right before increment), or the new one.
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
These have to be included always when nf_socket.h is included.
Signed-off-by: Máté Eckl <ecklm94@gmail.com>
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, they are:
1) Remove obsolete nf_log tracing from nf_tables, from Florian Westphal.
2) Add support for map lookups to numgen, random and hash expressions,
from Laura Garcia.
3) Allow to register nat hooks for iptables and nftables at the same
time. Patchset from Florian Westpha.
4) Timeout support for rbtree sets.
5) ip6_rpfilter works needs interface for link-local addresses, from
Vincent Bernat.
6) Add nf_ct_hook and nf_nat_hook structures and use them.
7) Do not drop packets on packets raceing to insert conntrack entries
into hashes, this is particularly a problem in nfqueue setups.
8) Address fallout from xt_osf separation to nf_osf, patches
from Florian Westphal and Fernando Mancera.
9) Remove reference to struct nft_af_info, which doesn't exist anymore.
From Taehee Yoo.
This batch comes with is a conflict between 25fd386e0b ("netfilter:
core: add missing __rcu annotation") in your tree and 2c205dd398
("netfilter: add struct nf_nat_hook and use it") coming in this batch.
This conflict can be solved by leaving the __rcu tag on
__netfilter_net_init() - added by 25fd386e0b - and remove all code
related to nf_nat_decode_session_hook - which is gone after
2c205dd398, as described by:
diff --cc net/netfilter/core.c
index e0ae4aae96f5,206fb2c4c319..168af54db975
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@@ -611,7 -580,13 +611,8 @@@ const struct nf_conntrack_zone nf_ct_zo
EXPORT_SYMBOL_GPL(nf_ct_zone_dflt);
#endif /* CONFIG_NF_CONNTRACK */
- static void __net_init __netfilter_net_init(struct nf_hook_entries **e, int max)
-#ifdef CONFIG_NF_NAT_NEEDED
-void (*nf_nat_decode_session_hook)(struct sk_buff *, struct flowi *);
-EXPORT_SYMBOL(nf_nat_decode_session_hook);
-#endif
-
+ static void __net_init
+ __netfilter_net_init(struct nf_hook_entries __rcu **e, int max)
{
int h;
I can also merge your net-next tree into nf-next, solve the conflict and
resend the pull request if you prefer so.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
Will be used in followup patch when nat types no longer
use nf_register_net_hook() but will instead register with the nat core.
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>
