linux.git/net/openvswitch/conntrack.c, branch v4.19

openvswitch: load NAT helper

2018-10-05T04:45:16+00:00

Load the respective NAT helper module if the flow uses it.

Signed-off-by: Flavio Leitner 
Signed-off-by: David S. Miller

Revert "openvswitch: Fix template leak in error cases."

2018-10-02T06:20:13+00:00

This reverts commit 90c7afc96cbbd77f44094b5b651261968e97de67.

When the commit was merged, the code used nf_ct_put() to free
the entry, but later on commit 76644232e612 ("openvswitch: Free
tmpl with tmpl_free.") replaced that with nf_ct_tmpl_free which
is a more appropriate. Now the original problem is removed.

Then 44d6e2f27328 ("net: Replace NF_CT_ASSERT() with WARN_ON().")
replaced a debug assert with a WARN_ON() which is trigged now.

Signed-off-by: Flavio Leitner 
Acked-by: Joe Stringer 
Signed-off-by: David S. Miller

ipv6: remove dependency of nf_defrag_ipv6 on ipv6 module

2018-07-18T09:26:53+00:00

IPV6=m
DEFRAG_IPV6=m
CONNTRACK=y yields:

net/netfilter/nf_conntrack_proto.o: In function `nf_ct_netns_do_get':
net/netfilter/nf_conntrack_proto.c:802: undefined reference to `nf_defrag_ipv6_enable'
net/netfilter/nf_conntrack_proto.o:(.rodata+0x640): undefined reference to `nf_conntrack_l4proto_icmpv6'

Setting DEFRAG_IPV6=y causes undefined references to ip6_rhash_params
ip6_frag_init and ip6_expire_frag_queue so it would be needed to force
IPV6=y too.

This patch gets rid of the 'followup linker error' by removing
the dependency of ipv6.ko symbols from netfilter ipv6 defrag.

Shared code is placed into a header, then used from both.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: Remove useless param helper of nf_ct_helper_ext_add

2018-07-18T09:26:42+00:00

The param helper of nf_ct_helper_ext_add is useless now, then remove
it now.

Signed-off-by: Gao Feng 
Signed-off-by: Pablo Neira Ayuso

openvswitch: use nf_ct_get_tuplepr, invert_tuplepr

2018-07-16T15:51:48+00:00

These versions deal with the l3proto/l4proto details internally.
It removes only caller of nf_ct_get_tuple, so make it static.

After this, l3proto->get_l4proto() can be removed in a followup patch.

Signed-off-by: Florian Westphal 
Acked-by: Pravin B Shelar 
Signed-off-by: Pablo Neira Ayuso

openvswitch: Support conntrack zone limit

2018-05-25T20:45:19+00:00

Currently, nf_conntrack_max is used to limit the maximum number of
conntrack entries in the conntrack table for every network namespace.
For the VMs and containers that reside in the same namespace,
they share the same conntrack table, and the total # of conntrack entries
for all the VMs and containers are limited by nf_conntrack_max.  In this
case, if one of the VM/container abuses the usage the conntrack entries,
it blocks the others from committing valid conntrack entries into the
conntrack table.  Even if we can possibly put the VM in different network
namespace, the current nf_conntrack_max configuration is kind of rigid
that we cannot limit different VM/container to have different # conntrack
entries.

To address the aforementioned issue, this patch proposes to have a
fine-grained mechanism that could further limit the # of conntrack entries
per-zone.  For example, we can designate different zone to different VM,
and set conntrack limit to each zone.  By providing this isolation, a
mis-behaved VM only consumes the conntrack entries in its own zone, and
it will not influence other well-behaved VMs.  Moreover, the users can
set various conntrack limit to different zone based on their preference.

The proposed implementation utilizes Netfilter's nf_conncount backend
to count the number of connections in a particular zone.  If the number of
connection is above a configured limitation, ovs will return ENOMEM to the
userspace.  If userspace does not configure the zone limit, the limit
defaults to zero that is no limitation, which is backward compatible to
the behavior without this patch.

The following high leve APIs are provided to the userspace:
  - OVS_CT_LIMIT_CMD_SET:
    * set default connection limit for all zones
    * set the connection limit for a particular zone
  - OVS_CT_LIMIT_CMD_DEL:
    * remove the connection limit for a particular zone
  - OVS_CT_LIMIT_CMD_GET:
    * get the default connection limit for all zones
    * get the connection limit for a particular zone

Signed-off-by: Yi-Hung Wei 
Acked-by: Pravin B Shelar 
Signed-off-by: David S. Miller

netfilter: add NAT support for shifted portmap ranges

2018-04-24T08:29:12+00:00

This is a patch proposal to support shifted ranges in portmaps.  (i.e. tcp/udp
incoming port 5000-5100 on WAN redirected to LAN 192.168.1.5:2000-2100)

Currently DNAT only works for single port or identical port ranges.  (i.e.
ports 5000-5100 on WAN interface redirected to a LAN host while original
destination port is not altered) When different port ranges are configured,
either 'random' mode should be used, or else all incoming connections are
mapped onto the first port in the redirect range. (in described example
WAN:5000-5100 will all be mapped to 192.168.1.5:2000)

This patch introduces a new mode indicated by flag NF_NAT_RANGE_PROTO_OFFSET
which uses a base port value to calculate an offset with the destination port
present in the incoming stream. That offset is then applied as index within the
redirect port range (index modulo rangewidth to handle range overflow).

In described example the base port would be 5000. An incoming stream with
destination port 5004 would result in an offset value 4 which means that the
NAT'ed stream will be using destination port 2004.

Other possibilities include deterministic mapping of larger or multiple ranges
to a smaller range : WAN:5000-5999 -> LAN:5000-5099 (maps WAN port 5*xx to port
51xx)

This patch does not change any current behavior. It just adds new NAT proto
range functionality which must be selected via the specific flag when intended
to use.

A patch for iptables (libipt_DNAT.c + libip6t_DNAT.c) will also be proposed
which makes this functionality immediately available.

Signed-off-by: Thierry Du Tre 
Signed-off-by: Pablo Neira Ayuso

openvswitch: Remove padding from packet before L3+ conntrack processing

2018-02-01T14:46:22+00:00

IPv4 and IPv6 packets may arrive with lower-layer padding that is not
included in the L3 length. For example, a short IPv4 packet may have
up to 6 bytes of padding following the IP payload when received on an
Ethernet device with a minimum packet length of 64 bytes.

Higher-layer processing functions in netfilter (e.g. nf_ip_checksum(),
and help() in nf_conntrack_ftp) assume skb->len reflects the length of
the L3 header and payload, rather than referring back to
ip_hdr->tot_len or ipv6_hdr->payload_len, and get confused by
lower-layer padding.

In the normal IPv4 receive path, ip_rcv() trims the packet to
ip_hdr->tot_len before invoking netfilter hooks. In the IPv6 receive
path, ip6_rcv() does the same using ipv6_hdr->payload_len. Similarly
in the br_netfilter receive path, br_validate_ipv4() and
br_validate_ipv6() trim the packet to the L3 length before invoking
netfilter hooks.

Currently in the OVS conntrack receive path, ovs_ct_execute() pulls
the skb to the L3 header but does not trim it to the L3 length before
calling nf_conntrack_in(NF_INET_PRE_ROUTING). When
nf_conntrack_proto_tcp encounters a packet with lower-layer padding,
nf_ip_checksum() fails causing a "nf_ct_tcp: bad TCP checksum" log
message. While extra zero bytes don't affect the checksum, the length
in the IP pseudoheader does. That length is based on skb->len, and
without trimming, it doesn't match the length the sender used when
computing the checksum.

In ovs_ct_execute(), trim the skb to the L3 length before higher-layer
processing.

Signed-off-by: Ed Swierk 
Acked-by: Pravin B Shelar 
Signed-off-by: David S. Miller

openvswitch: drop unneeded newline

2018-01-02T18:49:53+00:00

OVS_NLERR prints a newline at the end of the message string, so the
message string does not need to include a newline explicitly.  Done
using Coccinelle.

Signed-off-by: Julia Lawall 
Signed-off-by: David S. Miller

openvswitch: conntrack: mark expected switch fall-through

2017-10-22T01:01:26+00:00

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Notice that in this particular case I placed a "fall through" comment on
its own line, which is what GCC is expecting to find.

Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: David S. Miller