209 Commits
Author SHA1 Message Date
Pablo Neira Ayuso 93d7a7ed07 netfilter: flowtable: move path discovery infrastructure to its own file
This file contains the path discovery that is run from the forward chain
for the packet offloading the flow into the flowtable. This consists
of a series of calls to dev_fill_forward_path() for each device stack.

More topologies may be supported in the future, so move this code to its
own file to separate it from the nftables flow_offload expression.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2025-11-27 23:59:43 +00:00
Pablo Neira Ayuso fd72f265bb netfilter: conntrack: remove DCCP protocol support
The DCCP socket family has now been removed from this tree, see:

  8bb3212be4 ("Merge branch 'net-retire-dccp-socket'")

Remove connection tracking and NAT support for this protocol, this
should not pose a problem because no DCCP traffic is expected to be seen
on the wire.

As for the code for matching on dccp header for iptables and nftables,
mark it as deprecated and keep it in place. Ruleset restoration is an
atomic operation. Without dccp matching support, an astray match on dccp
could break this operation leaving your computer with no policy in
place, so let's follow a more conservative approach for matches.

Add CONFIG_NFT_EXTHDR_DCCP which is set to 'n' by default to deprecate
dccp extension support. Similarly, label CONFIG_NETFILTER_XT_MATCH_DCCP
as deprecated too and also set it to 'n' by default.

Code to match on DCCP protocol from ebtables also remains in place, this
is just a few checks on IPPROTO_DCCP from _check() path which is
exercised when ruleset is loaded. There is another use of IPPROTO_DCCP
from the _check() path in the iptables multiport match. Another check
for IPPROTO_DCCP from the packet in the reject target is also removed.

So let's schedule removal of the dccp matching for a second stage, this
should not interfer with the dccp retirement since this is only matching
on the dccp header.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2025-07-03 13:51:39 +02:00
Lorenzo BianconiandDaniel Borkmann 391bb6594f netfilter: Add bpf_xdp_flow_lookup kfunc
Introduce bpf_xdp_flow_lookup kfunc in order to perform the lookup
of a given flowtable entry based on a fib tuple of incoming traffic.
bpf_xdp_flow_lookup can be used as building block to offload in xdp
the processing of sw flowtable when hw flowtable is not available.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://lore.kernel.org/bpf/55d38a4e5856f6d1509d823ff4e98aaa6d356097.1719698275.git.lorenzo@kernel.org
2024-07-01 17:03:01 +02:00
Florian WestphalandDaniel Borkmann 89cc8f1c5f netfilter: nf_tables: Add flowtable map for xdp offload
This adds a small internal mapping table so that a new bpf (xdp) kfunc
can perform lookups in a flowtable.

As-is, xdp program has access to the device pointer, but no way to do a
lookup in a flowtable -- there is no way to obtain the needed struct
without questionable stunts.

This allows to obtain an nf_flowtable pointer given a net_device
structure.

In order to keep backward compatibility, the infrastructure allows the
user to add a given device to multiple flowtables, but it will always
return the first added mapping performing the lookup since it assumes
the right configuration is 1:1 mapping between flowtables and net_devices.

Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://lore.kernel.org/bpf/9f20e2c36f494b3bf177328718367f636bb0b2ab.1719698275.git.lorenzo@kernel.org
2024-07-01 17:01:53 +02:00
Breno LeitaoandIngo Molnar aefb2f2e61 x86/bugs: Rename CONFIG_RETPOLINE => CONFIG_MITIGATION_RETPOLINE
Step 5/10 of the namespace unification of CPU mitigations related Kconfig options.

[ mingo: Converted a few more uses in comments/messages as well. ]

Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Ariel Miculas <amiculas@cisco.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20231121160740.1249350-6-leitao@debian.org
2024-01-10 10:52:28 +01:00
Florian WestphalandAlexei Starovoitov 84601d6ee6 bpf: add bpf_link support for BPF_NETFILTER programs
Add bpf_link support skeleton.  To keep this reviewable, no bpf program
can be invoked yet, if a program is attached only a c-stub is called and
not the actual bpf program.

Defaults to 'y' if both netfilter and bpf syscall are enabled in kconfig.

Uapi example usage:
	union bpf_attr attr = { };

	attr.link_create.prog_fd = progfd;
	attr.link_create.attach_type = 0; /* unused */
	attr.link_create.netfilter.pf = PF_INET;
	attr.link_create.netfilter.hooknum = NF_INET_LOCAL_IN;
	attr.link_create.netfilter.priority = -128;

	err = bpf(BPF_LINK_CREATE, &attr, sizeof(attr));

... this would attach progfd to ipv4:input hook.

Such hook gets removed automatically if the calling program exits.

BPF_NETFILTER program invocation is added in followup change.

NF_HOOK_OP_BPF enum will eventually be read from nfnetlink_hook, it
allows to tell userspace which program is attached at the given hook
when user runs 'nft hook list' command rather than just the priority
and not-very-helpful 'this hook runs a bpf prog but I can't tell which
one'.

Will also be used to disallow registration of two bpf programs with
same priority in a followup patch.

v4: arm32 cmpxchg only supports 32bit operand
    s/prio/priority/
v3: restrict prog attachment to ip/ip6 for now, lets lift restrictions if
    more use cases pop up (arptables, ebtables, netdev ingress/egress etc).

Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20230421170300.24115-2-fw@strlen.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:34:14 -07:00
Xin LongandJakub Kicinski c0c3ab63de net: create nf_conntrack_ovs for ovs and tc use
Similar to nf_nat_ovs created by Commit ebddb14049 ("net: move the
nat function to nf_nat_ovs for ovs and tc"), this patch is to create
nf_conntrack_ovs to get these functions shared by OVS and TC only.

There are nf_ct_helper() and nf_ct_add_helper() from nf_conntrak_helper
in this patch, and will be more in the following patches.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-10 16:23:03 -08:00
Florian Westphal d9e7891476 netfilter: nf_tables: avoid retpoline overhead for some ct expression calls
nft_ct expression cannot be made builtin to nf_tables without also
forcing the conntrack itself to be builtin.

However, this can be avoided by splitting retrieval of a few
selector keys that only need to access the nf_conn structure,
i.e. no function calls to nf_conntrack code.

Many rulesets start with something like
"ct status established,related accept"

With this change, this no longer requires an indirect call, which
gives about 1.8% more throughput with a simple conntrack-enabled
forwarding test (retpoline thunk used).

Signed-off-by: Florian Westphal <fw@strlen.de>
2023-01-18 13:05:25 +01:00
Xin LongandDavid S. Miller ebddb14049 net: move the nat function to nf_nat_ovs for ovs and tc
There are two nat functions are nearly the same in both OVS and
TC code, (ovs_)ct_nat_execute() and ovs_ct_nat/tcf_ct_act_nat().

This patch creates nf_nat_ovs.c under netfilter and moves them
there then exports nf_ct_nat() so that it can be shared by both
OVS and TC, and keeps the nat (type) check and nat flag update
in OVS and TC's own place, as these parts are different between
OVS and TC.

Note that in OVS nat function it was using skb->protocol to get
the proto as it already skips vlans in key_extract(), while it
doesn't in TC, and TC has to call skb_protocol() to get proto.
So in nf_ct_nat_execute(), we keep using skb_protocol() which
works for both OVS and TC contrack.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Aaron Conole <aconole@redhat.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-12 10:14:03 +00:00
Pablo Neira Ayuso 3a07327d10 netfilter: nft_inner: support for inner tunnel header matching
This new expression allows you to match on the inner headers that are
encapsulated by any of the existing tunneling protocols.

This expression parses the inner packet to set the link, network and
transport offsets, so the existing expressions (with a few updates) can
be reused to match on the inner headers.

The inner expression supports for different tunnel combinations such as:

- ethernet frame over IPv4/IPv6 packet, eg. VxLAN.
- IPv4/IPv6 packet over IPv4/IPv6 packet, eg. IPIP.
- IPv4/IPv6 packet over IPv4/IPv6 + transport header, eg. GRE.
- transport header (ESP or SCTP) over transport header (usually UDP)

The following fields are used to describe the tunnel protocol:

- flags, which describe how to parse the inner headers:

  NFT_PAYLOAD_CTX_INNER_TUN, the tunnel provides its own header.
  NFT_PAYLOAD_CTX_INNER_ETHER, the ethernet frame is available as inner header.
  NFT_PAYLOAD_CTX_INNER_NH, the network header is available as inner header.
  NFT_PAYLOAD_CTX_INNER_TH, the transport header is available as inner header.

For example, VxLAN sets on all of these flags. While GRE only sets on
NFT_PAYLOAD_CTX_INNER_NH and NFT_PAYLOAD_CTX_INNER_TH. Then, ESP over
UDP only sets on NFT_PAYLOAD_CTX_INNER_TH.

The tunnel description is composed of the following attributes:

- header size: in case the tunnel comes with its own header, eg. VxLAN.

- type: this provides a hint to userspace on how to delinearize the rule.
  This is useful for VxLAN and Geneve since they run over UDP, since
  transport does not provide a hint. This is also useful in case hardware
  offload is ever supported. The type is not currently interpreted by the
  kernel.

- expression: currently only payload supported. Follow up patch adds
  also inner meta support which is required by autogenerated
  dependencies. The exthdr expression should be supported too
  at some point. There is a new inner_ops operation that needs to be
  set on to allow to use an existing expression from the inner expression.

This patch adds a new NFT_PAYLOAD_TUN_HEADER base which allows to match
on the tunnel header fields, eg. vxlan vni.

The payload expression is embedded into nft_inner private area and this
private data area is passed to the payload inner eval function via
direct call.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-10-25 13:48:42 +02:00
Florian WestphalandPablo Neira Ayuso d037abc241 netfilter: nft_objref: make it builtin
nft_objref is needed to reference named objects, it makes
no sense to disable it.

Before:
   text	   data	    bss	    dec	 filename
  4014	    424	      0	   4438	 nft_objref.o
  4174	   1128	      0	   5302	 nft_objref.ko
359351	  15276	    864	 375491	 nf_tables.ko
After:
  text	   data	    bss	    dec	 filename
  3815	    408	      0	   4223	 nft_objref.o
363161	  15692	    864	 379717	 nf_tables.ko

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-10-25 13:48:35 +02:00
Lorenzo BianconiandAlexei Starovoitov 820dc0523e net: netfilter: move bpf_ct_set_nat_info kfunc in nf_nat_bpf.c
Remove circular dependency between nf_nat module and nf_conntrack one
moving bpf_ct_set_nat_info kfunc in nf_nat_bpf.c

Fixes: 0fabd2aa19 ("net: netfilter: add bpf_ct_set_nat_info kfunc helper")
Suggested-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Yauheni Kaliuta <ykaliuta@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/51a65513d2cda3eeb0754842e8025ab3966068d8.1664490511.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-03 09:17:32 -07:00
Vlad BuslovandPablo Neira Ayuso b038177636 netfilter: nf_flow_table: count pending offload workqueue tasks
To improve hardware offload debuggability count pending 'add', 'del' and
'stats' flow_table offload workqueue tasks. Counters are incremented before
scheduling new task and decremented when workqueue handler finishes
executing. These counters allow user to diagnose congestion on hardware
offload workqueues that can happen when either CPU is starved and workqueue
jobs are executed at lower rate than new ones are added or when
hardware/driver can't keep up with the rate.

Implement the described counters as percpu counters inside new struct
netns_ft which is stored inside struct net. Expose them via new procfs file
'/proc/net/stats/nf_flowtable' that is similar to existing 'nf_conntrack'
file.

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-07-11 16:25:14 +02:00
Kumar Kartikeya DwivediandAlexei Starovoitov b4c2b9593a net/netfilter: Add unstable CT lookup helpers for XDP and TC-BPF
This change adds conntrack lookup helpers using the unstable kfunc call
interface for the XDP and TC-BPF hooks. The primary usecase is
implementing a synproxy in XDP, see Maxim's patchset [0].

Export get_net_ns_by_id as nf_conntrack_bpf.c needs to call it.

This object is only built when CONFIG_DEBUG_INFO_BTF_MODULES is enabled.

  [0]: https://lore.kernel.org/bpf/20211019144655.3483197-1-maximmi@nvidia.com

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220114163953.1455836-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-18 14:26:42 -08:00
Pablo Neira Ayuso 023223dfbf netfilter: nf_tables: make counter support built-in
Make counter support built-in to allow for direct call in case of
CONFIG_RETPOLINE.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-12-23 01:07:35 +01:00
Ryoga SaitoandPablo Neira Ayuso 7a3f5b0de3 netfilter: add netfilter hooks to SRv6 data plane
This patch introduces netfilter hooks for solving the problem that
conntrack couldn't record both inner flows and outer flows.

This patch also introduces a new sysctl toggle for enabling lightweight
tunnel netfilter hooks.

Signed-off-by: Ryoga Saito <contact@proelbtn.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-08-30 01:51:36 +02:00
Pablo Neira Ayuso 836382dc24 netfilter: nf_tables: add last expression
Add a new optional expression that tells you when last matching on a
given rule / set element element has happened.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-17 03:23:00 +02:00
Florian WestphalandPablo Neira Ayuso e2cf17d377 netfilter: add new hook nfnl subsystem
This nfnl subsystem allows to dump the list of all active netfiler hooks,
e.g. defrag, conntrack, nf/ip/arp/ip6tables and so on.

This helps to see what kind of features are currently enabled in
the network stack.

Sample output from nft tool using this infra:

 $ nft list hook ip input
 family ip hook input {
   +0000000010 nft_do_chain_inet [nf_tables] # nft table firewalld INPUT
   +0000000100 nf_nat_ipv4_local_in [nf_nat]
   +2147483647 ipv4_confirm [nf_conntrack]
 }

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-07 12:41:10 +02:00
Florian WestphalandPablo Neira Ayuso e465cccd0b netfilter: nf_log_common: merge with nf_log_syslog
Remove nf_log_common.  Now that all per-af modules have been merged
there is no longer a need to provide a helper module.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-03-31 22:34:10 +02:00
Florian WestphalandPablo Neira Ayuso 1510618e45 netfilter: nf_log_netdev: merge with nf_log_syslog
Provide netdev family support from the nf_log_syslog module.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-03-31 00:37:27 +02:00
Florian WestphalandPablo Neira Ayuso db3187ae21 netfilter: nf_log_ipv4: rename to nf_log_syslog
Netfilter has multiple log modules:
 nf_log_arp
 nf_log_bridge
 nf_log_ipv4
 nf_log_ipv6
 nf_log_netdev
 nfnetlink_log
 nf_log_common

With the exception of nfnetlink_log (packet is sent to userspace for
dissection/logging), all of them log to the kernel ringbuffer.

This is the first part of a series to merge all modules except
nfnetlink_log into a single module: nf_log_syslog.

This allows to reduce code.  After the series, only two log modules remain:
nfnetlink_log and nf_log_syslog. The latter provides the same
functionality as the old per-af log modules.

This renames nf_log_ipv4 to nf_log_syslog.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-03-31 00:37:27 +02:00
Jose M. Guisado GomezandPablo Neira Ayuso 6bbb9ad36c netfilter: nft_reject: add reject verdict support for netdev
Adds support for reject from ingress hook in netdev family.
Both stacks ipv4 and ipv6.  With reject packets supporting ICMP
and TCP RST.

This ability is required in devices that need to REJECT legitimate
clients which traffic is forwarded from the ingress hook.

Joint work with Laura Garcia.

Signed-off-by: Jose M. Guisado Gomez <guigom@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-10-31 10:41:00 +01:00
Jason A. DonenfeldandMasahiro Yamada e6abef610c x86: update AS_* macros to binutils >=2.23, supporting ADX and AVX2
Now that the kernel specifies binutils 2.23 as the minimum version, we
can remove ifdefs for AVX2 and ADX throughout.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-04-09 00:12:48 +09:00
Jason A. DonenfeldandMasahiro Yamada 5e8ebd841a x86: probe assembler capabilities via kconfig instead of makefile
Doing this probing inside of the Makefiles means we have a maze of
ifdefs inside the source code and child Makefiles that need to make
proper decisions on this too. Instead, we do it at Kconfig time, like
many other compiler and assembler options, which allows us to set up the
dependencies normally for full compilation units. In the process, the
ADX test changes to use %eax instead of %r10 so that it's valid in both
32-bit and 64-bit mode.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-04-09 00:01:59 +09:00
Stefano BrivioandPablo Neira Ayuso 7400b06396 nft_set_pipapo: Introduce AVX2-based lookup implementation
If the AVX2 set is available, we can exploit the repetitive
characteristic of this algorithm to provide a fast, vectorised
version by using 256-bit wide AVX2 operations for bucket loads and
bitwise intersections.

In most cases, this implementation consistently outperforms rbtree
set instances despite the fact they are configured to use a given,
single, ranged data type out of the ones used for performance
measurements by the nft_concat_range.sh kselftest.

That script, injecting packets directly on the ingoing device path
with pktgen, reports, averaged over five runs on a single AMD Epyc
7402 thread (3.35GHz, 768 KiB L1D$, 12 MiB L2$), the figures below.
CONFIG_RETPOLINE was not set here.

Note that this is not a fair comparison over hash and rbtree set
types: non-ranged entries (used to have a reference for hash types)
would be matched faster than this, and matching on a single field
only (which is the case for rbtree) is also significantly faster.

However, it's not possible at the moment to choose this set type
for non-ranged entries, and the current implementation also needs
a few minor adjustments in order to match on less than two fields.

 ---------------.-----------------------------------.------------.
 AMD Epyc 7402  |          baselines, Mpps          | this patch |
  1 thread      |___________________________________|____________|
  3.35GHz       |        |        |        |        |            |
  768KiB L1D$   | netdev |  hash  | rbtree |        |            |
 ---------------|  hook  |   no   | single |        |   pipapo   |
 type   entries |  drop  | ranges | field  | pipapo |    AVX2    |
 ---------------|--------|--------|--------|--------|------------|
 net,port       |        |        |        |        |            |
          1000  |   19.0 |   10.4 |    3.8 |    4.0 | 7.5   +87% |
 ---------------|--------|--------|--------|--------|------------|
 port,net       |        |        |        |        |            |
           100  |   18.8 |   10.3 |    5.8 |    6.3 | 8.1   +29% |
 ---------------|--------|--------|--------|--------|------------|
 net6,port      |        |        |        |        |            |
          1000  |   16.4 |    7.6 |    1.8 |    2.1 | 4.8  +128% |
 ---------------|--------|--------|--------|--------|------------|
 port,proto     |        |        |        |        |            |
         30000  |   19.6 |   11.6 |    3.9 |    0.5 | 2.6  +420% |
 ---------------|--------|--------|--------|--------|------------|
 net6,port,mac  |        |        |        |        |            |
            10  |   16.5 |    5.4 |    4.3 |    3.4 | 4.7   +38% |
 ---------------|--------|--------|--------|--------|------------|
 net6,port,mac, |        |        |        |        |            |
 proto    1000  |   16.5 |    5.7 |    1.9 |    1.4 | 3.6   +26% |
 ---------------|--------|--------|--------|--------|------------|
 net,mac        |        |        |        |        |            |
          1000  |   19.0 |    8.4 |    3.9 |    2.5 | 6.4  +156% |
 ---------------'--------'--------'--------'--------'------------'

A similar strategy could be easily reused to implement specialised
versions for other SIMD sets, and I plan to post at least a NEON
version at a later time.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-03-15 15:27:45 +01:00