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554 Commits (1b57e66384e2d21150301e68078526fac5680a16)

Author SHA1 Message Date
Florian Westphal 0a93aaedc4 netfilter: conntrack: use a single expectation table for all namespaces
We already include netns address in the hash and compare the netns pointers
during lookup, so even if namespaces have overlapping addresses entries
will be spread across the expectation table.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-06 11:50:01 +02:00
Pablo Neira Ayuso cb39ad8b8e netfilter: nf_tables: allow set names up to 32 bytes
Currently, we support set names of up to 16 bytes, get this aligned
with the maximum length we can use in ipset to make it easier when
considering migration to nf_tables.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05 16:39:51 +02:00
Pablo Neira Ayuso 71d8c47fc6 netfilter: conntrack: introduce clash resolution on insertion race
This patch introduces nf_ct_resolve_clash() to resolve race condition on
conntrack insertions.

This is particularly a problem for connection-less protocols such as
UDP, with no initial handshake. Two or more packets may race to insert
the entry resulting in packet drops.

Another problematic scenario are packets enqueued to userspace via
NFQUEUE after the raw table, that make it easier to trigger this
race.

To resolve this, the idea is to reset the conntrack entry to the one
that won race. Packet and bytes counters are also merged.

The 'insert_failed' stats still accounts for this situation, after
this patch, the drop counter is bumped whenever we drop packets, so we
can watch for unresolved clashes.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05 16:39:50 +02:00
Florian Westphal 56d52d4892 netfilter: conntrack: use a single hashtable for all namespaces
We already include netns address in the hash and compare the netns pointers
during lookup, so even if namespaces have overlapping addresses entries
will be spread across the table.

Assuming 64k bucket size, this change saves 0.5 mbyte per namespace on a
64bit system.

NAT bysrc and expectation hash is still per namespace, those will
changed too soon.

Future patch will also make conntrack object slab cache global again.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05 16:39:47 +02:00
Florian Westphal 141658fb02 netfilter: conntrack: use get_random_once for conntrack hash seed
As earlier commit removed accessed to the hash from other files we can
also make it static.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-25 14:52:12 +02:00
Florian Westphal adff6c6560 netfilter: connlabels: change nf_connlabels_get bit arg to 'highest used'
nf_connlabel_set() takes the bit number that we would like to set.
nf_connlabels_get() however took the number of bits that we want to
support.

So e.g. nf_connlabels_get(32) support bits 0 to 31, but not 32.
This changes nf_connlabels_get() to take the highest bit that we want
to set.

Callers then don't have to cope with a potential integer wrap
when using nf_connlabels_get(bit + 1) anymore.

Current callers are fine, this change is only to make folloup
nft ct label set support simpler.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-18 20:39:48 +02:00
Florian Westphal b4ef159927 netfilter: connlabels: move helpers to xt_connlabel
Currently labels can only be set either by iptables connlabel
match or via ctnetlink.

Before adding nftables set support, clean up the clabel core and move
helpers that nft will not need after all to the xtables module.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-18 20:39:41 +02:00
Florian Westphal ecdfb48cdd netfilter: conntrack: move expectation event helper to ecache.c
Not performance critical, it is only invoked when an expectation is
added/destroyed.

While at it, kill unused nf_ct_expect_event() wrapper.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-12 23:01:57 +02:00
Florian Westphal 3c435e2e41 netfilter: conntrack: de-inline nf_conntrack_eventmask_report
Way too large; move it to nf_conntrack_ecache.c.
Reduces total object size by 1216 byte on my machine.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-12 23:01:52 +02:00
Pablo Neira Ayuso 8a6bf5da1a netfilter: nft_masq: support port range
Complete masquerading support by allowing port range selection.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-02 20:05:27 +01:00
Sasha Levin b16c29191d netfilter: nf_conntrack: use safer way to lock all buckets
When we need to lock all buckets in the connection hashtable we'd attempt to
lock 1024 spinlocks, which is way more preemption levels than supported by
the kernel. Furthermore, this behavior was hidden by checking if lockdep is
enabled, and if it was - use only 8 buckets(!).

Fix this by using a global lock and synchronize all buckets on it when we
need to lock them all. This is pretty heavyweight, but is only done when we
need to resize the hashtable, and that doesn't happen often enough (or at all).

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-01-20 14:15:31 +01:00
Carlos Falgueras García e6d8ecac9e netfilter: nf_tables: Add new attributes into nft_set to store user data.
User data is stored at after 'nft_set_ops' private data into 'data[]'
flexible array. The field 'udata' points to user data and 'udlen' stores
its length.

Add new flag NFTA_SET_USERDATA.

Signed-off-by: Carlos Falgueras García <carlosfg@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-01-08 13:25:08 +01:00
Pablo Neira Ayuso 502061f81d netfilter: nf_tables: add packet duplication to the netdev family
You can use this to duplicate packets and inject them at the egress path
of the specified interface. This duplication allows you to inspect
traffic from the dummy or any other interface dedicated to this purpose.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-01-03 21:04:23 +01:00
Pablo Neira Ayuso 5ebe0b0eec netfilter: nf_tables: destroy basechain and rules on netdevice removal
If the netdevice is destroyed, the resources that are attached should
be released too as they belong to the device that is now gone.

Suggested-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-12-28 18:34:35 +01:00
Pablo Neira Ayuso df05ef874b netfilter: nf_tables: release objects on netns destruction
We have to release the existing objects on netns removal otherwise we
leak them. Chains are unregistered in first place to make sure no
packets are walking on our rules and sets anymore.

The object release happens by when we unregister the family via
nft_release_afinfo() which is called from nft_unregister_afinfo() from
the corresponding __net_exit path in every family.

Reported-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-12-28 18:34:35 +01:00
Pablo Neira 19576c9478 netfilter: cttimeout: add netns support
Add a per-netns list of timeout objects and adjust code to use it.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-12-14 12:48:58 +01:00
Florian Westphal e639f7ab07 netfilter: nf_tables: wrap tracing with a static key
Only needed when meta nftrace rule(s) were added.
The assumption is that no such rules are active, so the call to
nft_trace_init is "never" needed.

When nftrace rules are active, we always call the nft_trace_* functions,
but will only send netlink messages when all of the following are true:

 - traceinfo structure was initialised
 - skb->nf_trace == 1
 - at least one subscriber to trace group.

Adding an extra conditional
(static_branch ... && skb->nf_trace)
	nft_trace_init( ..)

Is possible but results in a larger nft_do_chain footprint.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-12-09 13:23:13 +01:00
Florian Westphal 33d5a7b14b netfilter: nf_tables: extend tracing infrastructure
nft monitor mode can then decode and display this trace data.

Parts of LL/Network/Transport headers are provided as separate
attributes.

Otherwise, printing IP address data becomes virtually impossible
for userspace since in the case of the netdev family we really don't
want userspace to have to know all the possible link layer types
and/or sizes just to display/print an ip address.

We also don't want userspace to have to follow ipv6 header chains
to get the s/dport info, the kernel already did this work for us.

To avoid bloating nft_do_chain all data required for tracing is
encapsulated in nft_traceinfo.

The structure is initialized unconditionally(!) for each nft_do_chain
invocation.

This unconditionall call will be moved under a static key in a
followup patch.

With lots of help from Patrick McHardy and Pablo Neira.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-12-09 13:18:37 +01:00
Patrick McHardy 7ec3f7b47b netfilter: nft_payload: add packet mangling support
Add support for mangling packet payload. Checksum for the specified base
header is updated automatically if requested, however no updates for any
kind of pseudo headers are supported, meaning no stateless NAT is supported.

For checksum updates different checksumming methods can be specified. The
currently supported methods are NONE for no checksum updates, and INET for
internet type checksums.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-11-25 13:54:51 +01:00
Florian Westphal a9ecfbe7fc netfilter: nf_tables: remove unused struct members
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-11-25 13:54:50 +01:00
Florian Westphal daaa7d647f netfilter: ipv6: avoid nf_iterate recursion
The previous patch changed nf_ct_frag6_gather() to morph reassembled skb
with the previous one.

This means that the return value is always NULL or the skb argument.
So change it to an err value.

Instead of invoking NF_HOOK recursively with threshold to skip already-called hooks
we can now just return NF_ACCEPT to move on to the next hook except for
-EINPROGRESS (which means skb has been queued for reassembly), in which case we
return NF_STOLEN.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-11-23 17:54:45 +01:00
Florian Westphal 029f7f3b87 netfilter: ipv6: nf_defrag: avoid/free clone operations
commit 6aafeef03b
("netfilter: push reasm skb through instead of original frag skbs")
changed ipv6 defrag to not use the original skbs anymore.

So rather than keeping the original skbs around just to discard them
afterwards just use the original skbs directly for the fraglist of
the newly assembled skb and remove the extra clone/free operations.

The skb that completes the fragment queue is morphed into a the
reassembled one instead, just like ipv4 defrag.

openvswitch doesn't need any additional skb_morph magic anymore to deal
with this situation so just remove that.

A followup patch can then also remove the NF_HOOK (re)invocation in
the ipv6 netfilter defrag hook.

Cc: Joe Stringer <joestringer@nicira.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-11-23 17:54:44 +01:00
Pablo Neira Ayuso 086f332167 netfilter: nf_tables: add clone interface to expression operations
With the conversion of the counter expressions to make it percpu, we
need to clone the percpu memory area, otherwise we crash when using
counters from flow tables.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-11-10 23:47:32 +01:00
Pablo Neira Ayuso f0a0a978b6 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
This merge resolves conflicts with 75aec9df3a ("bridge: Remove
br_nf_push_frag_xmit_sk") as part of Eric Biederman's effort to improve
netns support in the network stack that reached upstream via David's
net-next tree.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Conflicts:
	net/bridge/br_netfilter_hooks.c
2015-10-17 14:28:03 +02:00
Florian Westphal ed78d09d59 netfilter: make nf_queue_entry_get_refs return void
We don't care if module is being unloaded anymore since hook unregister
handling will destroy queue entries using that hook.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-16 18:22:23 +02:00
Eric W. Biederman b72775977c ipv6: Pass struct net into nf_ct_frag6_gather
The function nf_ct_frag6_gather is called on both the input and the
output paths of the networking stack.  In particular ipv6_defrag which
calls nf_ct_frag6_gather is called from both the the PRE_ROUTING chain
on input and the LOCAL_OUT chain on output.

The addition of a net parameter makes it explicit which network
namespace the packets are being reassembled in, and removes the need
for nf_ct_frag6_gather to guess.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12 19:44:17 -07:00
Pablo Neira Ayuso ae2d708ed8 netfilter: conntrack: fix crash on timeout object removal
The object and module refcounts are updated for each conntrack template,
however, if we delete the iptables rules and we flush the timeout
database, we may end up with invalid references to timeout object that
are just gone.

Resolve this problem by setting the timeout reference to NULL when the
custom timeout entry is removed from our base. This patch requires some
RCU trickery to ensure safe pointer handling.

This handling is similar to what we already do with conntrack helpers,
the idea is to avoid bumping the timeout object reference counter from
the packet path to avoid the cost of atomic ops.

Reported-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-12 17:04:34 +02:00
Flavio Leitner 0647e70834 netfilter: remove dead code
Remove __nf_conntrack_find() from headers.

Fixes: dcd93ed4cd ("netfilter: nf_conntrack: remove dead code")
Signed-off-by: Flavio Leitner <fbl@sysclose.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-05 17:32:01 +02:00
Pablo Neira Ayuso b7bd1809e0 netfilter: nfnetlink_queue: get rid of nfnetlink_queue_ct.c
The original intention was to avoid dependencies between nfnetlink_queue and
conntrack without ifdef pollution. However, we can achieve this by moving the
conntrack dependent code into ctnetlink and keep some glue code to access the
nfq_ct indirection from nfqueue.

After this patch, the nfq_ct indirection is always compiled in the netfilter
core to avoid polluting nfqueue with ifdefs. Thus, if nf_conntrack is not
compiled this results in only 8-bytes of memory waste in x86_64.

This patch also adds ctnetlink_nfqueue_seqadj() to avoid that the nf_conn
structure layout if exposed to nf_queue, which creates another dependency with
nf_conntrack at compilation time.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-04 21:45:44 +02:00
Eric W. Biederman c1444c6357 bridge: Pass net into br_validate_ipv4 and br_validate_ipv6
The network namespace is easiliy available in state->net so use it.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-29 20:21:32 +02:00
Eric W. Biederman 372892ec11 ipv4: Push struct net down into nf_send_reset
This is needed so struct net can be pushed down into
ip_route_me_harder.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-29 20:21:31 +02:00
Eric W. Biederman c7af6483b9 netfilter: Pass net into nf_xfrm_me_harder
Instead of calling dev_net on a likley looking network device
pass state->net into nf_xfrm_me_harder.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 22:00:22 +02:00
Eric W. Biederman 06198b34a3 netfilter: Pass priv instead of nf_hook_ops to netfilter hooks
Only pass the void *priv parameter out of the nf_hook_ops.  That is
all any of the functions are interested now, and by limiting what is
passed it becomes simpler to change implementation details.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 22:00:16 +02:00
Eric W. Biederman a31f1adc09 netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple
As gre does not have the srckey in the packet gre_pkt_to_tuple
needs to perform a lookup in it's per network namespace tables.

Pass in the proper network namespace to all pkt_to_tuple
implementations to ensure gre (and any similar protocols) can get this
right.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 22:00:04 +02:00
Eric W. Biederman 206e8c0075 netfilter: Pass net to nf_dup_ipv4 and nf_dup_ipv6
This allows them to stop guessing the network namespace with pick_net.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 21:59:11 +02:00
Eric W. Biederman 46448d0093 netfilter: nf_tables: Pass struct net in nft_pktinfo
nft_pktinfo is passed on the stack so this does not bloat any in core
data structures.

By centrally computing this information this makes maintence of the code
simpler, and understading of the code easier.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 21:58:38 +02:00
Eric W. Biederman 156c196f60 netfilter: x_tables: Pass struct net in xt_action_param
As xt_action_param lives on the stack this does not bloat any
persistent data structures.

This is a first step in making netfilter code that needs to know
which network namespace it is executing in simpler.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 21:58:14 +02:00
Eric W. Biederman 6aa187f21c netfilter: nf_tables: kill nft_pktinfo.ops
- Add nft_pktinfo.pf to replace ops->pf
- Add nft_pktinfo.hook to replace ops->hooknum

This simplifies the code, makes it more readable, and likely reduces
cache line misses.  Maintainability is enhanced as the details of
nft_hook_ops are of no concern to the recpients of nft_pktinfo.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 21:58:01 +02:00
Eric W. Biederman 0c4b51f005 netfilter: Pass net into okfn
This is immediately motivated by the bridge code that chains functions that
call into netfilter.  Without passing net into the okfns the bridge code would
need to guess about the best expression for the network namespace to process
packets in.

As net is frequently one of the first things computed in continuation functions
after netfilter has done it's job passing in the desired network namespace is in
many cases a code simplification.

To support this change the function dst_output_okfn is introduced to
simplify passing dst_output as an okfn.  For the moment dst_output_okfn
just silently drops the struct net.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:37 -07:00
David S. Miller 53cfd053e4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Conflicts:
	include/net/netfilter/nf_conntrack.h

The conflict was an overlap between changing the type of the zone
argument to nf_ct_tmpl_alloc() whilst exporting nf_ct_tmpl_free.

Pablo Neira Ayuso says:

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

The following patchset contains Netfilter fixes for net, they are:

1) Oneliner to restore maps in nf_tables since we support addressing registers
   at 32 bits level.

2) Restore previous default behaviour in bridge netfilter when CONFIG_IPV6=n,
   oneliner from Bernhard Thaler.

3) Out of bound access in ipset hash:net* set types, reported by Dave Jones'
   KASan utility, patch from Jozsef Kadlecsik.

4) Fix ipset compilation with gcc 4.4.7 related to C99 initialization of
   unnamed unions, patch from Elad Raz.

5) Add a workaround to address inconsistent endianess in the res_id field of
   nfnetlink batch messages, reported by Florian Westphal.

6) Fix error paths of CT/synproxy since the conntrack template was moved to use
   kmalloc, patch from Daniel Borkmann.

All of them look good to me to reach 4.2, I can route this to -stable myself
too, just let me know what you prefer.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-05 21:57:42 -07:00
Daniel Borkmann 62da98656b netfilter: nf_conntrack: make nf_ct_zone_dflt built-in
Fengguang reported, that some randconfig generated the following linker
issue with nf_ct_zone_dflt object involved:

  [...]
  CC      init/version.o
  LD      init/built-in.o
  net/built-in.o: In function `ipv4_conntrack_defrag':
  nf_defrag_ipv4.c:(.text+0x93e95): undefined reference to `nf_ct_zone_dflt'
  net/built-in.o: In function `ipv6_defrag':
  nf_defrag_ipv6_hooks.c:(.text+0xe3ffe): undefined reference to `nf_ct_zone_dflt'
  make: *** [vmlinux] Error 1

Given that configurations exist where we have a built-in part, which is
accessing nf_ct_zone_dflt such as the two handlers nf_ct_defrag_user()
and nf_ct6_defrag_user(), and a part that configures nf_conntrack as a
module, we must move nf_ct_zone_dflt into a fixed, guaranteed built-in
area when netfilter is configured in general.

Therefore, split the more generic parts into a common header under
include/linux/netfilter/ and move nf_ct_zone_dflt into the built-in
section that already holds parts related to CONFIG_NF_CONNTRACK in the
netfilter core. This fixes the issue on my side.

Fixes: 308ac9143e ("netfilter: nf_conntrack: push zone object into functions")
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-02 16:32:56 -07:00
Daniel Borkmann 9cf94eab8b netfilter: conntrack: use nf_ct_tmpl_free in CT/synproxy error paths
Commit 0838aa7fcf ("netfilter: fix netns dependencies with conntrack
templates") migrated templates to the new allocator api, but forgot to
update error paths for them in CT and synproxy to use nf_ct_tmpl_free()
instead of nf_conntrack_free().

Due to that, memory is being freed into the wrong kmemcache, but also
we drop the per net reference count of ct objects causing an imbalance.

In Brad's case, this leads to a wrap-around of net->ct.count and thus
lets __nf_conntrack_alloc() refuse to create a new ct object:

  [   10.340913] xt_addrtype: ipv6 does not support BROADCAST matching
  [   10.810168] nf_conntrack: table full, dropping packet
  [   11.917416] r8169 0000:07:00.0 eth0: link up
  [   11.917438] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
  [   12.815902] nf_conntrack: table full, dropping packet
  [   15.688561] nf_conntrack: table full, dropping packet
  [   15.689365] nf_conntrack: table full, dropping packet
  [   15.690169] nf_conntrack: table full, dropping packet
  [   15.690967] nf_conntrack: table full, dropping packet
  [...]

With slab debugging, it also reports the wrong kmemcache (kmalloc-512 vs.
nf_conntrack_ffffffff81ce75c0) and reports poison overwrites, etc. Thus,
to fix the problem, export and use nf_ct_tmpl_free() instead.

Fixes: 0838aa7fcf ("netfilter: fix netns dependencies with conntrack templates")
Reported-by: Brad Jackson <bjackson0971@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-01 12:15:08 +02:00
Joe Stringer 86ca02e774 netfilter: connlabels: Export setting connlabel length
Add functions to change connlabel length into nf_conntrack_labels.c so
they may be reused by other modules like OVS and nftables without
needing to jump through xt_match_check() hoops.

Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Florian Westphal <fw@strlen.de>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27 11:40:43 -07:00
Bernhard Thaler 18e1db67e9 netfilter: bridge: fix IPv6 packets not being bridged with CONFIG_IPV6=n
230ac490f7 introduced a dependency to CONFIG_IPV6 which breaks bridging
of IPv6 packets on a bridge with CONFIG_IPV6=n.

Sysctl entry /proc/sys/net/bridge/bridge-nf-call-ip6tables defaults to 1,
for this reason packets are handled by br_nf_pre_routing_ipv6(). When compiled
with CONFIG_IPV6=n this function returns NF_DROP but should return NF_ACCEPT
to let packets through.

Change CONFIG_IPV6=n br_nf_pre_routing_ipv6() return value to NF_ACCEPT.

Tested with a simple bridge with two interfaces and IPv6 packets trying
to pass from host on left side to host on right side of the bridge.

Fixes: 230ac490f7 ("netfilter: bridge: split ipv6 code into separated file")
Signed-off-by: Bernhard Thaler <bernhard.thaler@wvnet.at>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-19 21:21:41 +02:00
Pablo Neira Ayuso bf798657eb netfilter: nf_tables: Use 32 bit addressing register from nft_type_to_reg()
nft_type_to_reg() needs to return the register in the new 32 bit addressing,
otherwise we hit EINVAL when using mappings.

Fixes: 49499c3 ("netfilter: nf_tables: switch registers to 32 bit addressing")
Reported-by: Andreas Schultz <aschultz@tpip.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-19 21:21:41 +02:00
Daniel Borkmann 5e8018fc61 netfilter: nf_conntrack: add efficient mark to zone mapping
This work adds the possibility of deriving the zone id from the skb->mark
field in a scalable manner. This allows for having only a single template
serving hundreds/thousands of different zones, for example, instead of the
need to have one match for each zone as an extra CT jump target.

Note that we'd need to have this information attached to the template as at
the time when we're trying to lookup a possible ct object, we already need
to know zone information for a possible match when going into
__nf_conntrack_find_get(). This work provides a minimal implementation for
a possible mapping.

In order to not add/expose an extra ct->status bit, the zone structure has
been extended to carry a flag for deriving the mark.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-18 01:24:05 +02:00
Daniel Borkmann deedb59039 netfilter: nf_conntrack: add direction support for zones
This work adds a direction parameter to netfilter zones, so identity
separation can be performed only in original/reply or both directions
(default). This basically opens up the possibility of doing NAT with
conflicting IP address/port tuples from multiple, isolated tenants
on a host (e.g. from a netns) without requiring each tenant to NAT
twice resp. to use its own dedicated IP address to SNAT to, meaning
overlapping tuples can be made unique with the zone identifier in
original direction, where the NAT engine will then allocate a unique
tuple in the commonly shared default zone for the reply direction.
In some restricted, local DNAT cases, also port redirection could be
used for making the reply traffic unique w/o requiring SNAT.

The consensus we've reached and discussed at NFWS and since the initial
implementation [1] was to directly integrate the direction meta data
into the existing zones infrastructure, as opposed to the ct->mark
approach we proposed initially.

As we pass the nf_conntrack_zone object directly around, we don't have
to touch all call-sites, but only those, that contain equality checks
of zones. Thus, based on the current direction (original or reply),
we either return the actual id, or the default NF_CT_DEFAULT_ZONE_ID.
CT expectations are direction-agnostic entities when expectations are
being compared among themselves, so we can only use the identifier
in this case.

Note that zone identifiers can not be included into the hash mix
anymore as they don't contain a "stable" value that would be equal
for both directions at all times, f.e. if only zone->id would
unconditionally be xor'ed into the table slot hash, then replies won't
find the corresponding conntracking entry anymore.

If no particular direction is specified when configuring zones, the
behaviour is exactly as we expect currently (both directions).

Support has been added for the CT netlink interface as well as the
x_tables raw CT target, which both already offer existing interfaces
to user space for the configuration of zones.

Below a minimal, simplified collision example (script in [2]) with
netperf sessions:

  +--- tenant-1 ---+   mark := 1
  |    netperf     |--+
  +----------------+  |                CT zone := mark [ORIGINAL]
   [ip,sport] := X   +--------------+  +--- gateway ---+
                     | mark routing |--|     SNAT      |-- ... +
                     +--------------+  +---------------+       |
  +--- tenant-2 ---+  |                                     ~~~|~~~
  |    netperf     |--+                +-----------+           |
  +----------------+   mark := 2       | netserver |------ ... +
   [ip,sport] := X                     +-----------+
                                        [ip,port] := Y
On the gateway netns, example:

  iptables -t raw -A PREROUTING -j CT --zone mark --zone-dir ORIGINAL
  iptables -t nat -A POSTROUTING -o <dev> -j SNAT --to-source <ip> --random-fully

  iptables -t mangle -A PREROUTING -m conntrack --ctdir ORIGINAL -j CONNMARK --save-mark
  iptables -t mangle -A POSTROUTING -m conntrack --ctdir REPLY -j CONNMARK --restore-mark

conntrack dump from gateway netns:

  netperf -H 10.1.1.2 -t TCP_STREAM -l60 -p12865,5555 from each tenant netns

  tcp 6 431995 ESTABLISHED src=40.1.1.1 dst=10.1.1.2 sport=5555 dport=12865 zone-orig=1
                           src=10.1.1.2 dst=10.1.1.1 sport=12865 dport=1024
               [ASSURED] mark=1 secctx=system_u:object_r:unlabeled_t:s0 use=1

  tcp 6 431994 ESTABLISHED src=40.1.1.1 dst=10.1.1.2 sport=5555 dport=12865 zone-orig=2
                           src=10.1.1.2 dst=10.1.1.1 sport=12865 dport=5555
               [ASSURED] mark=2 secctx=system_u:object_r:unlabeled_t:s0 use=1

  tcp 6 299 ESTABLISHED src=40.1.1.1 dst=10.1.1.2 sport=39438 dport=33768 zone-orig=1
                        src=10.1.1.2 dst=10.1.1.1 sport=33768 dport=39438
               [ASSURED] mark=1 secctx=system_u:object_r:unlabeled_t:s0 use=1

  tcp 6 300 ESTABLISHED src=40.1.1.1 dst=10.1.1.2 sport=32889 dport=40206 zone-orig=2
                        src=10.1.1.2 dst=10.1.1.1 sport=40206 dport=32889
               [ASSURED] mark=2 secctx=system_u:object_r:unlabeled_t:s0 use=2

Taking this further, test script in [2] creates 200 tenants and runs
original-tuple colliding netperf sessions each. A conntrack -L dump in
the gateway netns also confirms 200 overlapping entries, all in ESTABLISHED
state as expected.

I also did run various other tests with some permutations of the script,
to mention some: SNAT in random/random-fully/persistent mode, no zones (no
overlaps), static zones (original, reply, both directions), etc.

  [1] http://thread.gmane.org/gmane.comp.security.firewalls.netfilter.devel/57412/
  [2] https://paste.fedoraproject.org/242835/65657871/

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-18 01:22:50 +02:00
Daniel Borkmann 308ac9143e netfilter: nf_conntrack: push zone object into functions
This patch replaces the zone id which is pushed down into functions
with the actual zone object. It's a bigger one-time change, but
needed for later on extending zones with a direction parameter, and
thus decoupling this additional information from all call-sites.

No functional changes in this patch.

The default zone becomes a global const object, namely nf_ct_zone_dflt
and will be returned directly in various cases, one being, when there's
f.e. no zoning support.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-11 12:29:01 +02:00
Pablo Neira Ayuso d877f07112 netfilter: nf_tables: add nft_dup expression
This new expression uses the nf_dup engine to clone packets to a given gateway.
Unlike xt_TEE, we use an index to indicate output interface which should be
fine at this stage.

Moreover, change to the preemtion-safe this_cpu_read(nf_skb_duplicated) from
nf_dup_ipv{4,6} to silence a lockdep splat.

Based on the original tee expression from Arturo Borrero Gonzalez, although
this patch has diverted quite a bit from this initial effort due to the
change to support maps.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-07 11:49:49 +02:00
Pablo Neira Ayuso bbde9fc182 netfilter: factor out packet duplication for IPv4/IPv6
Extracted from the xtables TEE target. This creates two new modules for IPv4
and IPv6 that are shared between the TEE target and the new nf_tables dup
expressions.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-07 11:49:49 +02:00