Commit Graph

171 Commits

Author SHA1 Message Date
Florian Westphal 7197743776 netfilter: conntrack: convert to refcount_t api
Convert nf_conn reference counting from atomic_t to refcount_t based api.
refcount_t api provides more runtime sanity checks and will warn on
certain constructs, e.g. refcount_inc() on a zero reference count, which
usually indicates use-after-free.

For this reason template allocation is changed to init the refcount to
1, the subsequenct add operations are removed.

Likewise, init_conntrack() is changed to set the initial refcount to 1
instead refcount_inc().

This is safe because the new entry is not (yet) visible to other cpus.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-01-09 23:30:13 +01:00
Jakub Kicinski 10905b4a68 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

1) Protect nft_ct template with global mutex, from Pavel Skripkin.

2) Two recent commits switched inet rt and nexthop exception hashes
   from jhash to siphash. If those two spots are problematic then
   conntrack is affected as well, so switch voer to siphash too.
   While at it, add a hard upper limit on chain lengths and reject
   insertion if this is hit. Patches from Florian Westphal.

3) Fix use-after-scope in nf_socket_ipv6 reported by KASAN,
   from Benjamin Hesmans.

* git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf:
  netfilter: socket: icmp6: fix use-after-scope
  netfilter: refuse insertion if chain has grown too large
  netfilter: conntrack: switch to siphash
  netfilter: conntrack: sanitize table size default settings
  netfilter: nft_ct: protect nft_ct_pcpu_template_refcnt with mutex
====================

Link: https://lore.kernel.org/r/20210903163020.13741-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-03 16:20:37 -07:00
Florian Westphal d7e7747ac5 netfilter: refuse insertion if chain has grown too large
Also add a stat counter for this that gets exported both via old /proc
interface and ctnetlink.

Assuming the old default size of 16536 buckets and max hash occupancy of
64k, this results in 128k insertions (origin+reply), so ~8 entries per
chain on average.

The revised settings in this series will result in about two entries per
bucket on average.

This allows a hard-limit ceiling of 64.

This is not tunable at the moment, but its possible to either increase
nf_conntrack_buckets or decrease nf_conntrack_max to reduce average
lengths.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-08-30 11:52:21 +02:00
Ryoga Saito 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
Florian Westphal 4592ee7f52 netfilter: conntrack: remove offload_pickup sysctl again
These two sysctls were added because the hardcoded defaults (2 minutes,
tcp, 30 seconds, udp) turned out to be too low for some setups.

They appeared in 5.14-rc1 so it should be fine to remove it again.

Marcelo convinced me that there should be no difference between a flow
that was offloaded vs. a flow that was not wrt. timeout handling.
Thus the default is changed to those for TCP established and UDP stream,
5 days and 120 seconds, respectively.

Marcelo also suggested to account for the timeout value used for the
offloading, this avoids increase beyond the value in the conntrack-sysctl
and will also instantly expire the conntrack entry with altered sysctls.

Example:
   nf_conntrack_udp_timeout_stream=60
   nf_flowtable_udp_timeout=60

This will remove offloaded udp flows after one minute, rather than two.

An earlier version of this patch also cleared the ASSURED bit to
allow nf_conntrack to evict the entry via early_drop (i.e., table full).
However, it looks like we can safely assume that connection timed out
via HW is still in established state, so this isn't needed.

Quoting Oz:
 [..] the hardware sends all packets with a set FIN flags to sw.
 [..] Connections that are aged in hardware are expected to be in the
 established state.

In case it turns out that back-to-sw-path transition can occur for
'dodgy' connections too (e.g., one side disappeared while software-path
would have been in RETRANS timeout), we can adjust this later.

Cc: Oz Shlomo <ozsh@nvidia.com>
Cc: Paul Blakey <paulb@nvidia.com>
Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Oz Shlomo <ozsh@nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-08-06 17:07:41 +02:00
Ali Abdallah 1da4cd82dd netfilter: conntrack: add new sysctl to disable RST check
This patch adds a new sysctl tcp_ignore_invalid_rst to disable marking
out of segments RSTs as INVALID.

Signed-off-by: Ali Abdallah <aabdallah@suse.de>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-07-06 14:15:12 +02:00
Oz Shlomo 975c57504d netfilter: conntrack: Introduce udp offload timeout configuration
UDP connections may be offloaded from nf conntrack to nf flow table.
Offloaded connections are aged after 30 seconds of inactivity.
Once aged, ownership is returned to conntrack with a hard coded pickup
time of 30 seconds, after which the connection may be deleted.
eted. The current aging intervals may be too aggressive for some users.

Provide users with the ability to control the nf flow table offload
aging and pickup time intervals via sysctl parameter as a pre-step for
configuring the nf flow table GC timeout intervals.

Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-07 12:23:37 +02:00
Oz Shlomo ef8ed5ea09 netfilter: conntrack: Introduce tcp offload timeout configuration
TCP connections may be offloaded from nf conntrack to nf flow table.
Offloaded connections are aged after 30 seconds of inactivity.
Once aged, ownership is returned to conntrack with a hard coded pickup
time of 120 seconds, after which the connection may be deleted.
eted. The current aging intervals may be too aggressive for some users.

Provide users with the ability to control the nf flow table offload
aging and pickup time intervals via sysctl parameter as a pre-step for
configuring the nf flow table GC timeout intervals.

Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-07 12:23:37 +02:00
Pablo Neira Ayuso 0418b989a4 netfilter: nftables: add nf_ct_pernet() helper function
Consolidate call to net_generic(net, nf_conntrack_net_id) in this
wrapper function.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-07 12:23:37 +02:00
David S. Miller 6dd06ec7c1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

1) Add vlan match and pop actions to the flowtable offload,
   patches from wenxu.

2) Reduce size of the netns_ct structure, which itself is
   embedded in struct net Make netns_ct a read-mostly structure.
   Patches from Florian Westphal.

3) Add FLOW_OFFLOAD_XMIT_UNSPEC to skip dst check from garbage
   collector path, as required by the tc CT action. From Roi Dayan.

4) VLAN offload fixes for nftables: Allow for matching on both s-vlan
   and c-vlan selectors. Fix match of VLAN id due to incorrect
   byteorder. Add a new routine to properly populate flow dissector
   ethertypes.

5) Missing keys in ip{6}_route_me_harder() results in incorrect
   routes. This includes an update for selftest infra. Patches
   from Ido Schimmel.

6) Add counter hardware offload support through FLOW_CLS_STATS.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-19 15:49:50 -07:00
Jakub Kicinski 8203c7ce4e Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
 - keep the ZC code, drop the code related to reinit
net/bridge/netfilter/ebtables.c
 - fix build after move to net_generic

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-04-17 11:08:07 -07:00
Florian Westphal 9b1a4d0f91 netfilter: conntrack: convert sysctls to u8
log_invalid sysctl allows values of 0 to 255 inclusive so we no longer
need a range check: the min/max values can be removed.

This also removes all member variables that were moved to net_generic
data in previous patches.

This reduces size of netns_ct struct by one cache line.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-04-13 13:10:39 +02:00
Florian Westphal c53bd0e966 netfilter: conntrack: move ct counter to net_generic data
Its only needed from slowpath (sysctl, ctnetlink, gc worker) and
when a new conntrack object is allocated.

Furthermore, each write dirties the otherwise read-mostly pernet
data in struct net.ct, which are accessed from packet path.

Move it to the net_generic data.  This makes struct netns_ct
read-mostly.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-04-13 13:10:39 +02:00
Florian Westphal 67f28216ca netfilter: conntrack: move autoassign_helper sysctl to net_generic data
While at it, make it an u8, no need to use an integer for a boolean.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-04-13 13:10:39 +02:00
Jonathon Reinhart 2671fa4dc0 netfilter: conntrack: Make global sysctls readonly in non-init netns
These sysctls point to global variables:
- NF_SYSCTL_CT_MAX (&nf_conntrack_max)
- NF_SYSCTL_CT_EXPECT_MAX (&nf_ct_expect_max)
- NF_SYSCTL_CT_BUCKETS (&nf_conntrack_htable_size_user)

Because their data pointers are not updated to point to per-netns
structures, they must be marked read-only in a non-init_net ns.
Otherwise, changes in any net namespace are reflected in (leaked into)
all other net namespaces. This problem has existed since the
introduction of net namespaces.

The current logic marks them read-only only if the net namespace is
owned by an unprivileged user (other than init_user_ns).

Commit d0febd81ae ("netfilter: conntrack: re-visit sysctls in
unprivileged namespaces") "exposes all sysctls even if the namespace is
unpriviliged." Since we need to mark them readonly in any case, we can
forego the unprivileged user check altogether.

Fixes: d0febd81ae ("netfilter: conntrack: re-visit sysctls in unprivileged namespaces")
Signed-off-by: Jonathon Reinhart <Jonathon.Reinhart@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-12 13:27:11 -07:00
Florian Westphal 7b5974709f netfilter: conntrack: move sysctl pointer to net_generic infra
No need to keep this in struct net, place it in the net_generic data.
The sysctl pointer is removed from struct net in a followup patch.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-04-06 00:34:53 +02:00
Pablo Neira Ayuso fbea31808c netfilter: conntrack: do not print icmpv6 as unknown via /proc
/proc/net/nf_conntrack shows icmpv6 as unknown.

Fixes: 09ec82f5af ("netfilter: conntrack: remove protocol name from l4proto struct")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-03-31 01:12:47 +02:00
Jesper Dangaard Brouer f6351c3f1c netfilter: conntrack: fix reading nf_conntrack_buckets
The old way of changing the conntrack hashsize runtime was through changing
the module param via file /sys/module/nf_conntrack/parameters/hashsize. This
was extended to sysctl change in commit 3183ab8997 ("netfilter: conntrack:
allow increasing bucket size via sysctl too").

The commit introduced second "user" variable nf_conntrack_htable_size_user
which shadow actual variable nf_conntrack_htable_size. When hashsize is
changed via module param this "user" variable isn't updated. This results in
sysctl net/netfilter/nf_conntrack_buckets shows the wrong value when users
update via the old way.

This patch fix the issue by always updating "user" variable when reading the
proc file. This will take care of changes to the actual variable without
sysctl need to be aware.

Fixes: 3183ab8997 ("netfilter: conntrack: allow increasing bucket size via sysctl too")
Reported-by: Yoel Caspersen <yoel@kviknet.dk>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-01-10 09:39:22 +01:00
Florian Westphal 1702ad79d3 netfilter: conntrack: proc: rename stat column
Rename 'searched' column to 'clashres' (same len).

conntrack(8) using the old /proc interface (ctnetlink not available) shows:

cpu=0  entries=4784 clashres=2292 [..]

Another alternative is to add another column, but this increases the
number of always-0 columns.

Fixes: bc92470413 ("netfilter: conntrack: add clash resolution stat counter")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-09-22 01:33:35 +02:00
Florian Westphal bc92470413 netfilter: conntrack: add clash resolution stat counter
There is a misconception about what "insert_failed" means.

We increment this even when a clash got resolved, so it might not indicate
a problem.

Add a dedicated counter for clash resolution and only increment
insert_failed if a clash cannot be resolved.

For the old /proc interface, export this in place of an older stat
that got removed a while back.
For ctnetlink, export this with a new attribute.

Also correct an outdated comment that implies we add a duplicate tuple --
we only add the (unique) reply direction.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-08-28 19:51:26 +02:00
Florian Westphal 4afc41dfa5 netfilter: conntrack: remove ignore stats
This counter increments when nf_conntrack_in sees a packet that already
has a conntrack attached or when the packet is marked as UNTRACKED.
Neither is an error.

The former is normal for loopback traffic.  The second happens for
certain ICMPv6 packets or when nftables/ip(6)tables rules are in place.

In case someone needs to count UNTRACKED packets, or packets
that are marked as untracked before conntrack_in this can be done with
both nftables and ip(6)tables rules.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-08-28 19:51:26 +02:00
Gustavo A. R. Silva 954d82979b netfilter: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-07-22 01:18:05 +02:00
David S. Miller 115506fea4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-05-01 (v2)

The following pull-request contains BPF updates for your *net-next* tree.

We've added 61 non-merge commits during the last 6 day(s) which contain
a total of 153 files changed, 6739 insertions(+), 3367 deletions(-).

The main changes are:

1) pulled work.sysctl from vfs tree with sysctl bpf changes.

2) bpf_link observability, from Andrii.

3) BTF-defined map in map, from Andrii.

4) asan fixes for selftests, from Andrii.

5) Allow bpf_map_lookup_elem for SOCKMAP and SOCKHASH, from Jakub.

6) production cloudflare classifier as a selftes, from Lorenz.

7) bpf_ktime_get_*_ns() helper improvements, from Maciej.

8) unprivileged bpftool feature probe, from Quentin.

9) BPF_ENABLE_STATS command, from Song.

10) enable bpf_[gs]etsockopt() helpers for sock_ops progs, from Stanislav.

11) enable a bunch of common helpers for cg-device, sysctl, sockopt progs,
 from Stanislav.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-01 17:02:27 -07:00
Christoph Hellwig 32927393dc sysctl: pass kernel pointers to ->proc_handler
Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from  userspace in common code.  This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.

As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-27 02:07:40 -04:00
Bodong Wang 74f99482ea netfilter: nf_conntrack: add IPS_HW_OFFLOAD status bit
This bit indicates that the conntrack entry is offloaded to hardware
flow table. nf_conntrack entry will be tagged with [HW_OFFLOAD] if
it's offload to hardware.

cat /proc/net/nf_conntrack
	ipv4 2 tcp 6 \
	src=1.1.1.17 dst=1.1.1.16 sport=56394 dport=5001 \
	src=1.1.1.16 dst=1.1.1.17 sport=5001 dport=56394 [HW_OFFLOAD] \
	mark=0 zone=0 use=3

Note that HW_OFFLOAD/OFFLOAD/ASSURED are mutually exclusive.

Changelog:

* V1->V2:
- Remove check of lastused from stats. It was meant for cases such
  as removing driver module while traffic still running. Better to
  handle such cases from garbage collector.

Signed-off-by: Bodong Wang <bodong@mellanox.com>
Reviewed-by: Oz Shlomo <ozsh@mellanox.com>
Reviewed-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-04-26 23:54:35 +02:00
Florian Westphal d0febd81ae netfilter: conntrack: re-visit sysctls in unprivileged namespaces
since commit b884fa4617 ("netfilter: conntrack: unify sysctl handling")
conntrack no longer exposes most of its sysctls (e.g. tcp timeouts
settings) to network namespaces that are not owned by the initial user
namespace.

This patch exposes all sysctls even if the namespace is unpriviliged.

compared to a 4.19 kernel, the newly visible and writeable sysctls are:
  net.netfilter.nf_conntrack_acct
  net.netfilter.nf_conntrack_timestamp
  .. to allow to enable accouting and timestamp extensions.

  net.netfilter.nf_conntrack_events
  .. to turn off conntrack event notifications.

  net.netfilter.nf_conntrack_checksum
  .. to disable checksum validation.

  net.netfilter.nf_conntrack_log_invalid
  .. to enable logging of packets deemed invalid by conntrack.

newly visible sysctls that are only exported as read-only:

  net.netfilter.nf_conntrack_count
  .. current number of conntrack entries living in this netns.

  net.netfilter.nf_conntrack_max
  .. global upperlimit (maximum size of the table).

  net.netfilter.nf_conntrack_buckets
  .. size of the conntrack table (hash buckets).

  net.netfilter.nf_conntrack_expect_max
  .. maximum number of permitted expectations in this netns.

  net.netfilter.nf_conntrack_helper
  .. conntrack helper auto assignment.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-03-15 15:27:51 +01:00
Vasily Averin dc15af8e9d netfilter: nf_conntrack: ct_cpu_seq_next should increase position index
If .next function does not change position index,
following .show function will repeat output related
to current position index.

Cc: stable@vger.kernel.org
Fixes: 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration code ...")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-03-04 02:27:18 +01:00
Jeremy Sowden 261db6c2fb netfilter: conntrack: move code to linux/nf_conntrack_common.h.
Move some `struct nf_conntrack` code from linux/skbuff.h to
linux/nf_conntrack_common.h.  Together with a couple of helpers for
getting and setting skb->_nfct, it allows us to remove
CONFIG_NF_CONNTRACK checks from net/netfilter/nf_conntrack.h.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-09-13 12:47:11 +02:00
David S. Miller 765b7590c9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
r8152 conflicts are the NAPI fixes in 'net' overlapping with
some tasklet stuff in net-next

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-02 11:20:17 -07:00
Florian Westphal 478553fd1b netfilter: conntrack: make sysctls per-namespace again
When I merged the extension sysctl tables with the main one I forgot to
reset them on netns creation.  They currently read/write init_net settings.

Fixes: d912dec124 ("netfilter: conntrack: merge acct and helper sysctl table with main one")
Fixes: cb2833ed00 ("netfilter: conntrack: merge ecache and timestamp sysctl tables with main one")
Reported-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-08-27 17:46:13 +02:00
Matteo Croce e84fb4b366 netfilter: conntrack: use shared sysctl constants
Use shared sysctl variables for zero and one constants, as in commit
eec4844fae ("proc/sysctl: add shared variables for range check")

Fixes: 8f14c99c7e ("netfilter: conntrack: limit sysctl setting for boolean options")
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-08-03 18:39:08 +02:00
Tonghao Zhang 8f14c99c7e netfilter: conntrack: limit sysctl setting for boolean options
We use the zero and one to limit the boolean options setting.
After this patch we only set 0 or 1 to boolean options for nf
conntrack sysctl.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-04-30 14:18:56 +02:00
Cong Wang ac088a88b5 netfilter: conntrack: fix error path in nf_conntrack_pernet_init()
When nf_ct_netns_get() fails, it should clean up itself,
its caller doesn't need to call nf_conntrack_fini_net().

nf_conntrack_init_net() is called after registering sysctl
and proc, so its cleanup function should be called before
unregistering sysctl and proc.

Fixes: ba3fbe6636 ("netfilter: nf_conntrack: provide modparam to always register conntrack hooks")
Fixes: b884fa4617 ("netfilter: conntrack: unify sysctl handling")
Reported-and-tested-by: syzbot+fcee88b2d87f0539dfe9@syzkaller.appspotmail.com
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-28 11:32:55 +01:00
Pablo Neira Ayuso ba3fbe6636 netfilter: nf_conntrack: provide modparam to always register conntrack hooks
The connection tracking hooks can be optionally registered per netns
when conntrack is specifically invoked from the ruleset since
0c66dc1ea3 ("netfilter: conntrack: register hooks in netns when needed
by ruleset"). Then, since 4d3a57f23d ("netfilter: conntrack: do not
enable connection tracking unless needed"), the default behaviour is
changed to always register them on demand.

This patch provides a toggle that allows users to always register them.
Without this toggle, in order to use conntrack for statistics
collection, you need a dummy rule that refers to conntrack, eg.

        iptables -I INPUT -m state --state NEW

This patch allows users to restore the original behaviour via modparam,
ie. always register connection tracking, eg.

        modprobe nf_conntrack enable_hooks=1

Hence, no dummy rule is required.

Reported-by: Laura Garcia <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal 4a60dc748d netfilter: conntrack: remove nf_ct_l4proto_find_get
Its now same as __nf_ct_l4proto_find(), so rename that to
nf_ct_l4proto_find and use it everywhere.

It never returns NULL and doesn't need locks or reference counts.

Before this series:
302824  net/netfilter/nf_conntrack.ko
 21504  net/netfilter/nf_conntrack_proto_gre.ko

  text	   data	    bss	    dec	    hex	filename
  6281	   1732	      4	   8017	   1f51	nf_conntrack_proto_gre.ko
108356	  20613	    236	 129205	  1f8b5	nf_conntrack.ko

After:
294864  net/netfilter/nf_conntrack.ko
  text	   data	    bss	    dec	    hex	filename
106979	  19557	    240	 126776	  1ef38	nf_conntrack.ko

so, even with builtin gre, total size got reduced.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal b884fa4617 netfilter: conntrack: unify sysctl handling
Due to historical reasons, all l4 trackers register their own
sysctls.

This leads to copy&pasted boilerplate code, that does exactly same
thing, just with different data structure.

Place all of this in a single file.

This allows to remove the various ctl_table pointers from the ct_netns
structure and reduces overall code size.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal cb2833ed00 netfilter: conntrack: merge ecache and timestamp sysctl tables with main one
Similar to previous change, this time for eache and timestamp.
Unlike helper and acct, these can be disabled at build time, so they
need ifdef guards.

Next patch will remove a few (now obsolete) functions.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-21 00:51:51 +01:00
Florian Westphal d912dec124 netfilter: conntrack: merge acct and helper sysctl table with main one
Needless copy&paste, just handle all in one.  Next patch will handle
acct and timestamp, which have similar functions.

Intentionally leaves cruft behind, will be cleaned up in a followup
patch.

The obsolete sysctl pointers in netns_ct struct are left in place and
removed in a single change, as changes to netns trigger rebuild of
almost all files.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-21 00:51:48 +01:00
Florian Westphal 4a65798a94 netfilter: conntrack: add mnemonics for sysctl table
Its a bit hard to see what table[3] really lines up with, so add
human-readable mnemonics and use them for initialisation.

This makes it easier to see e.g. which sysctls are not exported to
unprivileged userns.

objdiff shows no changes.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-21 00:51:44 +01:00
Florian Westphal 4b216e21cf netfilter: conntrack: un-export seq_print_acct
Only one caller, just place it where its needed.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-21 00:51:39 +01:00
Florian Westphal dd2934a957 netfilter: conntrack: remove l3->l4 mapping information
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>
2018-09-20 18:07:35 +02:00
Florian Westphal 2953d80ff0 netfilter: remove obsolete need_conntrack stub
as of a0ae2562c6 ("netfilter: conntrack: remove l3proto
abstraction") there are no users anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-17 11:40:07 +02:00
Florian Westphal a0ae2562c6 netfilter: conntrack: remove l3proto abstraction
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>
2018-07-17 15:27:49 +02:00
Florian Westphal f957be9d34 netfilter: conntrack: remove ctnetlink callbacks from l3 protocol trackers
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>
2018-07-16 17:54:58 +02:00
Christoph Hellwig c350637227 proc: introduce proc_create_net{,_data}
Variants of proc_create{,_data} that directly take a struct seq_operations
and deal with network namespaces in ->open and ->release.  All callers of
proc_create + seq_open_net converted over, and seq_{open,release}_net are
removed entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16 07:24:30 +02:00
Kirill Tkhai 2f635ceeb2 net: Drop pernet_operations::async
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-27 13:18:09 -04:00
Joe Perches d6444062f8 net: Use octal not symbolic permissions
Prefer the direct use of octal for permissions.

Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace
and some typing.

Miscellanea:

o Whitespace neatening around these conversions.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-26 12:07:48 -04:00
Kirill Tkhai 467d14b307 net: Convert nf_conntrack_net_ops
These pernet_operations register and unregister sysctl and /proc
entries. Exit batch method also waits till all per-net conntracks
are dead. Thus, they are safe to be marked as async.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-05 10:48:28 -05:00
Alexey Dobriyan 4c87158dae netfilter: delete /proc THIS_MODULE references
/proc has been ignoring struct file_operations::owner field for 10 years.
Specifically, it started with commit 786d7e1612
("Fix rmmod/read/write races in /proc entries"). Notice the chunk where
inode->i_fop is initialized with proxy struct file_operations for
regular files:

	-               if (de->proc_fops)
	-                       inode->i_fop = de->proc_fops;
	+               if (de->proc_fops) {
	+                       if (S_ISREG(inode->i_mode))
	+                               inode->i_fop = &proc_reg_file_ops;
	+                       else
	+                               inode->i_fop = de->proc_fops;
	+               }

VFS stopped pinning module at this point.

# ipvs
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-19 14:10:53 +01:00
Pablo Neira Ayuso 90964016e5 netfilter: nf_conntrack: add IPS_OFFLOAD status bit
This new bit tells us that the conntrack entry is owned by the flow
table offload infrastructure.

 # cat /proc/net/nf_conntrack
 ipv4     2 tcp      6 src=10.141.10.2 dst=147.75.205.195 sport=36392 dport=443 src=147.75.205.195 dst=192.168.2.195 sport=443 dport=36392 [OFFLOAD] mark=0 zone=0 use=2

Note the [OFFLOAD] tag in the listing.

The timer of such conntrack entries look like stopped from userspace.
In practise, to make sure the conntrack entry does not go away, the
conntrack timer is periodically set to an arbitrary large value that
gets refreshed on every iteration from the garbage collector, so it
never expires- and they display no internal state in the case of TCP
flows. This allows us to save a bitcheck from the packet path via
nf_ct_is_expired().

Conntrack entries that have been offloaded to the flow table
infrastructure cannot be deleted/flushed via ctnetlink. The flow table
infrastructure is also responsible for releasing this conntrack entry.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:11:05 +01:00