Currently, we check the existing rtable in PREROUTING hook, if RTCF_LOCAL
is set, we assume that the packet is loopback.
But this assumption is incorrect, for example, a packet encapsulated
in ipsec transport mode was received and routed to local, after
decapsulation, it would be delivered to local again, and the rtable
was not dropped, so RTCF_LOCAL check would trigger. But actually, the
packet was not loopback.
So for these normal loopback packets, we can check whether the in device
is IFF_LOOPBACK or not. For these locally generated broadcast/multicast,
we can check whether the skb->pkt_type is PACKET_LOOPBACK or not.
Finally, there's a subtle difference between nft fib expr and xtables
rpfilter extension, user can add the following nft rule to do strict
rpfilter check:
# nft add rule x y meta iif eth0 fib saddr . iif oif != eth0 drop
So when the packet is loopback, it's better to store the in device
instead of the LOOPBACK_IFINDEX, otherwise, after adding the above
nft rule, locally generated broad/multicast packets will be dropped
incorrectly.
Fixes: f83a7ea207 ("netfilter: xt_rpfilter: skip locally generated broadcast/multicast, too")
Fixes: f6d0cbcf09 ("netfilter: nf_tables: add fib expression")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter/IPVS updates for net-next
The following patchset contains a large Netfilter update for net-next,
to summarise:
1) Add support for stateful objects. This series provides a nf_tables
native alternative to the extended accounting infrastructure for
nf_tables. Two initial stateful objects are supported: counters and
quotas. Objects are identified by a user-defined name, you can fetch
and reset them anytime. You can also use a maps to allow fast lookups
using any arbitrary key combination. More info at:
http://marc.info/?l=netfilter-devel&m=148029128323837&w=2
2) On-demand registration of nf_conntrack and defrag hooks per netns.
Register nf_conntrack hooks if we have a stateful ruleset, ie.
state-based filtering or NAT. The new nf_conntrack_default_on sysctl
enables this from newly created netnamespaces. Default behaviour is not
modified. Patches from Florian Westphal.
3) Allocate 4k chunks and then use these for x_tables counter allocation
requests, this improves ruleset load time and also datapath ruleset
evaluation, patches from Florian Westphal.
4) Add support for ebpf to the existing x_tables bpf extension.
From Willem de Bruijn.
5) Update layer 4 checksum if any of the pseudoheader fields is updated.
This provides a limited form of 1:1 stateless NAT that make sense in
specific scenario, eg. load balancing.
6) Add support to flush sets in nf_tables. This series comes with a new
set->ops->deactivate_one() indirection given that we have to walk
over the list of set elements, then deactivate them one by one.
The existing set->ops->deactivate() performs an element lookup that
we don't need.
7) Two patches to avoid cloning packets, thus speed up packet forwarding
via nft_fwd from ingress. From Florian Westphal.
8) Two IPVS patches via Simon Horman: Decrement ttl in all modes to
prevent infinite loops, patch from Dwip Banerjee. And one minor
refactoring from Gao feng.
9) Revisit recent log support for nf_tables netdev families: One patch
to ensure that we correctly handle non-ethernet packets. Another
patch to add missing logger definition for netdev. Patches from
Liping Zhang.
10) Three patches for nft_fib, one to address insufficient register
initialization and another to solve incorrect (although harmless)
byteswap operation. Moreover update xt_rpfilter and nft_fib to match
lbcast packets with zeronet as source, eg. DHCP Discover packets
(0.0.0.0 -> 255.255.255.255). Also from Liping Zhang.
11) Built-in DCCP, SCTP and UDPlite conntrack and NAT support, from
Davide Caratti. While DCCP is rather hopeless lately, and UDPlite has
been broken in many-cast mode for some little time, let's give them a
chance by placing them at the same level as other existing protocols.
Thus, users don't explicitly have to modprobe support for this and
NAT rules work for them. Some people point to the lack of support in
SOHO Linux-based routers that make deployment of new protocols harder.
I guess other middleboxes outthere on the Internet are also to blame.
Anyway, let's see if this has any impact in the midrun.
12) Skip software SCTP software checksum calculation if the NIC comes
with SCTP checksum offload support. From Davide Caratti.
13) Initial core factoring to prepare conversion to hook array. Three
patches from Aaron Conole.
14) Gao Feng made a wrong conversion to switch in the xt_multiport
extension in a patch coming in the previous batch. Fix it in this
batch.
15) Get vmalloc call in sync with kmalloc flags to avoid a warning
and likely OOM killer intervention from x_tables. From Marcelo
Ricardo Leitner.
16) Update Arturo Borrero's email address in all source code headers.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support for set flushing, that consists of walking over
the set elements if the NFTA_SET_ELEM_LIST_ELEMENTS attribute is set.
This patch requires the following changes:
1) Add set->ops->deactivate_one() operation: This allows us to
deactivate an element from the set element walk path, given we can
skip the lookup that happens in ->deactivate().
2) Add a new nft_trans_alloc_gfp() function since we need to allocate
transactions using GFP_ATOMIC given the set walk path happens with
held rcu_read_lock.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch allows you to refer to stateful objects from set elements.
This provides the infrastructure to create maps where the right hand
side of the mapping is a stateful object.
This allows us to build dictionaries of stateful objects, that you can
use to perform fast lookups using any arbitrary key combination.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Notify on depleted quota objects. The NFT_QUOTA_F_DEPLETED flag
indicates we have reached overquota.
Add pointer to table from nft_object, so we can use it when sending the
depletion notification to userspace.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Introduce nf_tables_obj_notify() to notify internal state changes in
stateful objects. This is used by the quota object to report depletion
in a follow up patch.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds a new NFT_MSG_GETOBJ_RESET command perform an atomic
dump-and-reset of the stateful object. This also comes with add support
for atomic dump and reset for counter and quota objects.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch augments nf_tables to support stateful objects. This new
infrastructure allows you to create, dump and delete stateful objects,
that are identified by a user-defined name.
This patch adds the generic infrastructure, follow up patches add
support for two stateful objects: counters and quotas.
This patch provides a native infrastructure for nf_tables to replace
nfacct, the extended accounting infrastructure for iptables.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
... so we can use current skb instead of working with a clone.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds a new flag that signals the kernel to update layer 4
checksum if the packet field belongs to the layer 4 pseudoheader. This
implicitly provides stateless NAT 1:1 that is useful under very specific
usecases.
Since rules mangling layer 3 fields that are part of the pseudoheader
may potentially convey any layer 4 packet, we have to deal with the
layer 4 checksum adjustment using protocol specific code.
This patch adds support for TCP, UDP and ICMPv6, since they include the
pseudoheader in the layer 4 checksum calculation. ICMP doesn't, so we
can skip it.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_defrag modules for ipv4 and ipv6 export an empty stub function.
Any module that needs the defragmentation hooks registered simply 'calls'
this empty function to create a phony module dependency -- modprobe will
then load the defrag module too.
This extends netfilter ipv4/ipv6 defragmentation modules to delay the hook
registration until the functionality is requested within a network namespace
instead of module load time for all namespaces.
Hooks are only un-registered on module unload or when a namespace that used
such defrag functionality exits.
We have to use struct net for this as the register hooks can be called
before netns initialization here from the ipv4/ipv6 conntrack module
init path.
There is no unregister functionality support, defrag will always be
active once it was requested inside a net namespace.
The reason is that defrag has impact on nft and iptables rulesets
(without defrag we might see framents).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
1) Old code was hard to maintain, due to complex lock chains.
(We probably will be able to remove some kfree_rcu() in callers)
2) Using a single timer to update all estimators does not scale.
3) Code was buggy on 32bit kernel (WRITE_ONCE() on 64bit quantity
is not supposed to work well)
In this rewrite :
- I removed the RB tree that had to be scanned in
gen_estimator_active(). qdisc dumps should be much faster.
- Each estimator has its own timer.
- Estimations are maintained in net_rate_estimator structure,
instead of dirtying the qdisc. Minor, but part of the simplification.
- Reading the estimator uses RCU and a seqcount to provide proper
support for 32bit kernels.
- We reduce memory need when estimators are not used, since
we store a pointer, instead of the bytes/packets counters.
- xt_rateest_mt() no longer has to grab a spinlock.
(In the future, xt_rateest_tg() could be switched to per cpu counters)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This switch (default on) can be used to disable automatic registration
of connection tracking functionality in newly created network
namespaces.
This means that when net namespace goes down (or the tracker protocol
module is unloaded) we *might* have to unregister the hooks.
We can either add another per-netns variable that tells if
the hooks got registered by default, or, alternatively, just call
the protocol _put() function and have the callee deal with a possible
'extra' put() operation that doesn't pair with a get() one.
This uses the latter approach, i.e. a put() without a get has no effect.
Conntrack is still enabled automatically regardless of the new sysctl
setting if the new net namespace requires connection tracking, e.g. when
NAT rules are created.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This makes use of nf_ct_netns_get/put added in previous patch.
We add get/put functions to nf_conntrack_l3proto structure, ipv4 and ipv6
then implement use-count to track how many users (nft or xtables modules)
have a dependency on ipv4 and/or ipv6 connection tracking functionality.
When count reaches zero, the hooks are unregistered.
This delays activation of connection tracking inside a namespace until
stateful firewall rule or nat rule gets added.
This patch breaks backwards compatibility in the sense that connection
tracking won't be active anymore when the protocol tracker module is
loaded. This breaks e.g. setups that ctnetlink for flow accounting and
the like, without any '-m conntrack' packet filter rules.
Followup patch restores old behavour and makes new delayed scheme
optional via sysctl.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
currently aliased to try_module_get/_put.
Will be changed in next patch when we add functions to make use of ->net
argument to store usercount per l3proto tracker.
This is needed to avoid registering the conntrack hooks in all netns and
later only enable connection tracking in those that need conntrack.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
since adf0516845 ("netfilter: remove ip_conntrack* sysctl compat code")
the only user (ipv4 tracker) sets this to an empty stub function.
After this change nf_ct_l3proto_pernet_register() is also empty,
but this will change in a followup patch to add conditional register
of the hooks.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CONFIG_NF_CT_PROTO_UDPLITE is no more a tristate. When set to y,
connection tracking support for UDPlite protocol is built-in into
nf_conntrack.ko.
footprint test:
$ ls -l net/netfilter/nf_conntrack{_proto_udplite,}.ko \
net/ipv4/netfilter/nf_conntrack_ipv4.ko \
net/ipv6/netfilter/nf_conntrack_ipv6.ko
(builtin)|| udplite| ipv4 | ipv6 |nf_conntrack
---------++--------+--------+--------+--------------
none || 432538 | 828755 | 828676 | 6141434
UDPlite || - | 829649 | 829362 | 6498204
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CONFIG_NF_CT_PROTO_SCTP is no more a tristate. When set to y, connection
tracking support for SCTP protocol is built-in into nf_conntrack.ko.
footprint test:
$ ls -l net/netfilter/nf_conntrack{_proto_sctp,}.ko \
net/ipv4/netfilter/nf_conntrack_ipv4.ko \
net/ipv6/netfilter/nf_conntrack_ipv6.ko
(builtin)|| sctp | ipv4 | ipv6 | nf_conntrack
---------++--------+--------+--------+--------------
none || 498243 | 828755 | 828676 | 6141434
SCTP || - | 829254 | 829175 | 6547872
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CONFIG_NF_CT_PROTO_DCCP is no more a tristate. When set to y, connection
tracking support for DCCP protocol is built-in into nf_conntrack.ko.
footprint test:
$ ls -l net/netfilter/nf_conntrack{_proto_dccp,}.ko \
net/ipv4/netfilter/nf_conntrack_ipv4.ko \
net/ipv6/netfilter/nf_conntrack_ipv6.ko
(builtin)|| dccp | ipv4 | ipv6 | nf_conntrack
---------++--------+--------+--------+--------------
none || 469140 | 828755 | 828676 | 6141434
DCCP || - | 830566 | 829935 | 6533526
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In netdev family, we will handle non ethernet packets, so using
eth_hdr(skb)->h_proto is incorrect.
Meanwhile, we can use socket(AF_PACKET...) to sending packets, so
skb->protocol is not always set in bridge family.
Add an extra parameter into nf_log_l2packet to solve this issue.
Fixes: 1fddf4bad0 ("netfilter: nf_log: add packet logging for netdev family")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CONFIG_NF_NAT_PROTO_UDPLITE is no more a tristate. When set to y, NAT
support for UDPlite protocol is built-in into nf_nat.ko.
footprint test:
(nf_nat_proto_) |udplite || nf_nat
--------------------------+--------++--------
no builtin | 408048 || 2241312
UDPLITE builtin | - || 2577256
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CONFIG_NF_NAT_PROTO_SCTP is no more a tristate. When set to y, NAT
support for SCTP protocol is built-in into nf_nat.ko.
footprint test:
(nf_nat_proto_) | sctp || nf_nat
--------------------------+--------++--------
no builtin | 428344 || 2241312
SCTP builtin | - || 2597032
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CONFIG_NF_NAT_PROTO_DCCP is no more a tristate. When set to y, NAT
support for DCCP protocol is built-in into nf_nat.ko.
footprint test:
(nf_nat_proto_) | dccp || nf_nat
--------------------------+--------++--------
no builtin | 409800 || 2241312
DCCP builtin | - || 2578968
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Couple conflicts resolved here:
1) In the MACB driver, a bug fix to properly initialize the
RX tail pointer properly overlapped with some changes
to support variable sized rings.
2) In XGBE we had a "CONFIG_PM" --> "CONFIG_PM_SLEEP" fix
overlapping with a reorganization of the driver to support
ACPI, OF, as well as PCI variants of the chip.
3) In 'net' we had several probe error path bug fixes to the
stmmac driver, meanwhile a lot of this code was cleaned up
and reorganized in 'net-next'.
4) The cls_flower classifier obtained a helper function in
'net-next' called __fl_delete() and this overlapped with
Daniel Borkamann's bug fix to use RCU for object destruction
in 'net'. It also overlapped with Jiri's change to guard
the rhashtable_remove_fast() call with a check against
tc_skip_sw().
5) In mlx4, a revert bug fix in 'net' overlapped with some
unrelated changes in 'net-next'.
6) In geneve, a stale header pointer after pskb_expand_head()
bug fix in 'net' overlapped with a large reorganization of
the same code in 'net-next'. Since the 'net-next' code no
longer had the bug in question, there was nothing to do
other than to simply take the 'net-next' hunks.
Signed-off-by: David S. Miller <davem@davemloft.net>
