Those are all useless or dubious.
getorigdst() is called via setsockopt, so return value/errno will
already indicate an appropriate error.
For other pr_debug calls there are better replacements, such as
slab/slub debugging or 'conntrack -E' (ctnetlink events).
Signed-off-by: Florian Westphal <fw@strlen.de>
smatch warnings:
net/netfilter/nf_conntrack_proto.c:167 nf_confirm() warn: unsigned 'protoff' is never less than zero.
We need to check if ipv6_skip_exthdr() returned an error, but protoff is
unsigned. Use a signed integer for this.
Fixes: a70e483460 ("netfilter: conntrack: merge ipv4+ipv6 confirm functions")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
No need to have distinct functions. After merge, ipv6 can avoid
protooff computation if the connection neither needs sequence adjustment
nor helper invocation -- this is the normal case.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds a structure to collect all the context data that is
passed to the cleanup iterator.
struct nf_ct_iter_data {
struct net *net;
void *data;
u32 portid;
int report;
};
There is a netns field that allows to clean up conntrack entries
specifically owned by the specified netns.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The VRF driver invokes netfilter for output+postrouting hooks so that users
can create rules that check for 'oif $vrf' rather than lower device name.
Afterwards, ip stack calls those hooks again.
This is a problem when conntrack is used with IP masquerading.
masquerading has an internal check that re-validates the output
interface to account for route changes.
This check will trigger in the vrf case.
If the -j MASQUERADE rule matched on the first iteration, then round 2
finds state->out->ifindex != nat->masq_index: the latter is the vrf
index, but out->ifindex is the lower device.
The packet gets dropped and the conntrack entry is invalidated.
This change makes conntrack postrouting skip the nat hooks.
Also skip confirmation. This allows the second round
(postrouting invocation from ipv4/ipv6) to create nat bindings.
This also prevents the second round from seeing packets that had their
source address changed by the nat hook.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
nf_ct_gre_keymap_flush() is useless.
It is called from nf_conntrack_cleanup_net_list() only and tries to remove
nf_ct_gre_keymap entries from pernet gre keymap list. Though:
a) at this point the list should already be empty, all its entries were
deleted during the conntracks cleanup, because
nf_conntrack_cleanup_net_list() executes nf_ct_iterate_cleanup(kill_all)
before nf_conntrack_proto_pernet_fini():
nf_conntrack_cleanup_net_list
+- nf_ct_iterate_cleanup
| nf_ct_put
| nf_conntrack_put
| nf_conntrack_destroy
| destroy_conntrack
| destroy_gre_conntrack
| nf_ct_gre_keymap_destroy
`- nf_conntrack_proto_pernet_fini
nf_ct_gre_keymap_flush
b) Let's say we find that the keymap list is not empty. This means netns
still has a conntrack associated with gre, in which case we should not free
its memory, because this will lead to a double free and related crashes.
However I doubt it could have gone unnoticed for years, obviously
this does not happen in real life. So I think we can remove
both nf_ct_gre_keymap_flush() and nf_conntrack_proto_pernet_fini().
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The packet logger backend is unable to provide the incoming (or
outgoing) interface name because that information isn't available.
Pass the hook state, it contains the network namespace, the protocol
family, the network interfaces and other things.
Signed-off-by: Florian Westphal <fw@strlen.de>
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 net-next:
1) Add nfgenmsg field to nfnetlink's struct nfnl_info and use it.
2) Remove nft_ctx_init_from_elemattr() and nft_ctx_init_from_setattr()
helper functions.
3) Add the nf_ct_pernet() helper function to fetch the conntrack
pernetns data area.
4) Expose TCP and UDP flowtable offload timeouts through sysctl,
from Oz Shlomo.
5) Add nfnetlink_hook subsystem to fetch the netfilter hook
pipeline configuration, from Florian Westphal. This also includes
a new field to annotate the hook type as metadata.
6) Fix unsafe memory access to non-linear skbuff in the new SCTP
chunk support for nft_exthdr, from Phil Sutter.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
When ipv6 sockopt register fails, the ipv4 one needs to be removed.
Fixes: a0ae2562c6 ("netfilter: conntrack: remove l3proto abstraction")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When I changed defrag hooks to no longer get registered by default I
intentionally made it so that registration can only be un-done by unloading
the nf_defrag_ipv4/6 module.
In hindsight this was too conservative; there is no reason to keep defrag
on while there is no feature dependency anymore.
Moreover, this won't work if user isn't allowed to remove nf_defrag module.
This adds the disable() functions for both ipv4 and ipv6 and calls them
from conntrack, TPROXY and the xtables socket module.
ipvs isn't converted here, it will behave as before this patch and
will need module removal.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The openvswitch module fails initialization when used in a kernel
without IPv6 enabled. nf_conncount_init() fails because the ct code
unconditionally tries to initialize the netns IPv6 related bit,
regardless of the build option. The change below ignores the IPv6
part if not enabled.
Note that the corresponding _put() function already has this IPv6
configuration check.
Fixes: 11efd5cb04 ("openvswitch: Support conntrack zone limit")
Signed-off-by: Eelco Chaudron <echaudro@redhat.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch enables IPv4 and IPv6 conntrack from the bridge to deal with
local traffic. Hence, packets that are passed up to the local input path
are confirmed later on from the {ipv4,ipv6}_confirm() hooks.
For packets leaving the IP stack (ie. output path), fragmentation occurs
after the inet postrouting hook. Therefore, the bridge local out and
postrouting bridge hooks see fragments with conntrack objects, which is
inconsistent. In this case, we could defragment again from the bridge
output hook, but this is expensive. The recommended filtering spot for
outgoing locally generated traffic leaving through the bridge interface
is to use the classic IPv4/IPv6 output hook, which comes earlier.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds basic connection tracking support for the bridge,
including initial IPv4 support.
This patch register two hooks to deal with the bridge forwarding path,
one from the bridge prerouting hook to call nf_conntrack_in(); and
another from the bridge postrouting hook to confirm the entry.
The conntrack bridge prerouting hook defragments packets before passing
them to nf_conntrack_in() to look up for an existing entry, otherwise a
new entry is allocated and it is attached to the skbuff. The conntrack
bridge postrouting hook confirms new conntrack entries, ie. if this is
the first packet seen, then it adds the entry to the hashtable and (if
needed) it refragments the skbuff into the original fragments, leaving
the geometry as is if possible. Exceptions are linearized skbuffs, eg.
skbuffs that are passed up to nfqueue and conntrack helpers, as well as
cloned skbuff for the local delivery (eg. tcpdump), also in case of
bridge port flooding (cloned skbuff too).
The packet defragmentation is done through the ip_defrag() call. This
forces us to save the bridge control buffer, reset the IP control buffer
area and then restore it after call. This function also bumps the IP
fragmentation statistics, it would be probably desiderable to have
independent statistics for the bridge defragmentation/refragmentation.
The maximum fragment length is stored in the control buffer and it is
used to refragment the skbuff from the postrouting path.
The new fraglist splitter and fragment transformer APIs are used to
implement the bridge refragmentation code. The br_ip_fragment() function
drops the packet in case the maximum fragment size seen is larger than
the output port MTU.
This patchset follows the principle that conntrack should not drop
packets, so users can do it through policy via invalid state matching.
Like br_netfilter, there is no refragmentation for packets that are
passed up for local delivery, ie. prerouting -> input path. There are
calls to nf_reset() already in several spots in the stack since time ago
already, eg. af_packet, that show that skbuff fraglist handling from the
netif_rx path is supported already.
The helpers are called from the postrouting hook, before confirmation,
from there we may see packet floods to bridge ports. Then, although
unlikely, this may result in exercising the helpers many times for each
clone. It would be good to explore how to pass all the packets in a list
to the conntrack hook to do this handle only once for this case.
Thanks to Florian Westphal for handing me over an initial patchset
version to add support for conntrack bridge.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds infrastructure to register and to unregister bridge
support for the conntrack module via nf_ct_bridge_register() and
nf_ct_bridge_unregister().
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
It doesn't log a packet if sysctl_log_invalid isn't equal to protonum
OR sysctl_log_invalid isn't equal to IPPROTO_RAW. This sentence is
always true. I believe we need to replace OR to AND.
Cc: Florian Westphal <fw@strlen.de>
Fixes: c4f3db1595 ("netfilter: conntrack: add and use nf_l4proto_log_invalid")
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stephen Rothwell reports:
After merging the netfilter-next tree, today's linux-next build
(powerpc ppc64_defconfig) failed like this:
ERROR: "nf_conntrack_invert_icmpv6_tuple" [nf_conntrack.ko] undefined!
ERROR: "nf_conntrack_icmpv6_packet" [nf_conntrack.ko] undefined!
ERROR: "nf_conntrack_icmpv6_init_net" [nf_conntrack.ko] undefined!
ERROR: "icmpv6_pkt_to_tuple" [nf_conntrack.ko] undefined!
ERROR: "nf_ct_gre_keymap_destroy" [nf_conntrack.ko] undefined!
icmpv6 related errors are due to lack of IS_ENABLED(CONFIG_IPV6) (no
icmpv6 support is builtin if kernel has CONFIG_IPV6=n), the
nf_ct_gre_keymap_destroy error is due to lack of PROTO_GRE check.
Fixes: a47c540481 ("netfilter: conntrack: handle builtin l4proto packet functions via direct calls")
Fixes: e2e48b4716 ("netfilter: conntrack: handle icmp pkt_to_tuple helper via direct calls")
Fixes: 197c4300ae ("netfilter: conntrack: remove invert_tuple callback")
Fixes: 2a389de86e ("netfilter: conntrack: remove l4proto init and get_net callbacks")
Fixes: e56894356f ("netfilter: conntrack: remove l4proto destroy hook")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
Those were needed we still had modular trackers.
As we don't have those anymore, prefer direct calls and remove all
the (un)register infrastructure associated with this.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
No need to get/put module owner reference, none of these can be removed
anymore.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This makes the last of the modular l4 trackers 'bool'.
After this, all infrastructure to handle dynamic l4 protocol registration
becomes obsolete and can be removed in followup patches.
Old:
302824 net/netfilter/nf_conntrack.ko
21504 net/netfilter/nf_conntrack_proto_gre.ko
New:
313728 net/netfilter/nf_conntrack.ko
Old:
text data bss dec hex filename
6281 1732 4 8017 1f51 nf_conntrack_proto_gre.ko
108356 20613 236 129205 1f8b5 nf_conntrack.ko
New:
112095 21381 240 133716 20a54 nf_conntrack.ko
The size increase is only temporary.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
place them into the confirm one.
Old:
hook (300): ipv4/6_help() first call helper, then seqadj.
hook (INT_MAX): confirm
Now:
hook (INT_MAX): confirm, first call helper, then seqadj, then confirm
Not having the extra call is noticeable in bechmarks.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
All higher l4proto numbers are handled by the generic tracker; the
l4proto lookup function already returns generic one in case the l4proto
number exceeds max size.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
l4 protocols are demuxed by l3num, l4num pair.
However, almost all l4 trackers are l3 agnostic.
Only exceptions are:
- gre, icmp (ipv4 only)
- icmpv6 (ipv6 only)
This commit gets rid of the l3 mapping, l4 trackers can now be looked up
by their IPPROTO_XXX value alone, which gets rid of the additional l3
indirection.
For icmp, ipcmp6 and gre, add a check on state->pf and
return -NF_ACCEPT in case we're asked to track e.g. icmpv6-in-ipv4,
this seems more fitting than using the generic tracker.
Additionally we can kill the 2nd l4proto definitions that were needed
for v4/v6 split -- they are now the same so we can use single l4proto
struct for each protocol, rather than two.
The EXPORT_SYMBOLs can be removed as all these object files are
part of nf_conntrack with no external references.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Its unused, next patch will remove l4proto->l3proto number to simplify
l4 protocol demuxer lookup.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_hook_state contains all the hook meta-information: netns, protocol family,
hook location, and so on.
Instead of only passing selected information, pass a pointer to entire
structure.
This will allow to merge the error and the packet handlers and remove
the ->new() function in followup patches.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Doug Smythies says:
Sometimes it is desirable to temporarily disable, or clear,
the iptables rule set on a computer being controlled via a
secure shell session (SSH). While unwise on an internet facing
computer, I also do it often on non-internet accessible computers
while testing. Recently, this has become problematic, with the
SSH session being dropped upon re-load of the rule set.
The problem is that when all rules are deleted, conntrack hooks get
unregistered.
In case the rules are re-added later, its possible that tcp window
has moved far enough so that all packets are considered invalid (out of
window) until entry expires (which can take forever, default
established timeout is 5 days).
Fix this by clearing maxwin of existing tcp connections on register.
v2: don't touch entries on hook removal.
v3: remove obsolete expiry check.
Reported-by: Doug Smythies <dsmythies@telus.net>
Fixes: 4d3a57f23d ("netfilter: conntrack: do not enable connection tracking unless needed")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_ct_l4proto_unregister_one() leaves conntracks added by
to-be-removed tracker behind, nf_ct_l4proto_unregister has to iterate
for each protocol to be removed.
v2: call nf_ct_iterate_destroy without holding nf_ct_proto_mutex.
Fixes: 2c41f33c1b ("netfilter: move table iteration out of netns exit paths")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When the conntrack module is removed, we call nf_ct_iterate_destroy via
nf_ct_l4proto_unregister().
Problem is that nf_conntrack_proto_fini() gets called after the
conntrack hash table has already been freed.
Just remove the l4proto unregister call, its unecessary as the
nf_ct_protos[] array gets free'd right after anyway.
v2: add comment wrt. missing unreg call.
Fixes: a0ae2562c6 ("netfilter: conntrack: remove l3proto abstraction")
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>
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>
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>
similar to previous commit, but instead compute this at compile time
and turn nlattr_size into an u16.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
So we can call this from other expression that need conntrack in place
to work.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Florian Westphal <fw@strlen.de>
We currently call ->nlattr_tuple_size() once at register time and
cache result in l4proto->nla_size.
nla_size is the only member that is written to, avoiding this would
allow to make l4proto trackers const.
We can use ->nlattr_tuple_size() at run time, and cache result in
the individual trackers instead.
This is an intermediate step, next patch removes nlattr_size()
callback and computes size at compile time, then removes nla_size.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We currently pass down the l4 protocol to the conntrack ->packet()
function, but the only user of this is the debug info decision.
Same information can be derived from struct nf_conn.
Add a wrapper for the previous patch that extracs the information
from nf_conn and passes it to nf_l4proto_log_invalid().
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We currently pass down the l4 protocol to the conntrack ->packet()
function, but the only user of this is the debug info decision.
Same information can be derived from struct nf_conn.
As a first step, add and use a new log function for this, similar to
nf_ct_helper_log().
Add __cold annotation -- invalid packets should be infrequent so
gcc can consider all call paths that lead to such a function as
unlikely.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Doesn't change generated code, but will make it easier to eventually
make the actual trackers themselvers const.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
no need to waste storage for something that is only needed
in one place and can be deduced from protocol number.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
avoids a pointer and allows struct to be const later on.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When a nf_conntrack_l3/4proto parameter is not on the left hand side
of an assignment, its address is not taken, and it is not passed to a
function that may modify its fields, then it can be declared as const.
This change is useful from a documentation point of view, and can
possibly facilitate making some nf_conntrack_l3/4proto structures const
subsequently.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Discussion during NFWS 2017 in Faro has shown that the current
conntrack behaviour is unreasonable.
Even if conntrack module is loaded on behalf of a single net namespace,
its turned on for all namespaces, which is expensive. Commit
481fa37347 ("netfilter: conntrack: add nf_conntrack_default_on sysctl")
attempted to provide an alternative to the 'default on' behaviour by
adding a sysctl to change it.
However, as Eric points out, the sysctl only becomes available
once the module is loaded, and then its too late.
So we either have to move the sysctl to the core, or, alternatively,
change conntrack to become active only once the rule set requires this.
This does the latter, conntrack is only enabled when a rule needs it.
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Florian Westphal