linux.git/net/bridge/br_forward.c, branch v4.3

bridge: Fix network header pointer for vlan tagged packets

2015-07-29T19:20:16+00:00

There are several devices that can receive vlan tagged packets with
CHECKSUM_PARTIAL like tap, possibly veth and xennet.
When (multiple) vlan tagged packets with CHECKSUM_PARTIAL are forwarded
by bridge to a device with the IP_CSUM feature, they end up with checksum
error because before entering bridge, the network header is set to
ETH_HLEN (not including vlan header length) in __netif_receive_skb_core(),
get_rps_cpu(), or drivers' rx functions, and nobody fixes the pointer later.

Since the network header is exepected to be ETH_HLEN in flow-dissection
and hash-calculation in RPS in rx path, and since the header pointer fix
is needed only in tx path, set the appropriate network header on forwarding
packets.

Signed-off-by: Toshiaki Makita 
Signed-off-by: David S. Miller

bridge: fix potential crash in __netdev_pick_tx()

2015-07-10T05:48:42+00:00

Commit c29390c6dfee ("xps: must clear sender_cpu before forwarding")
fixed an issue in normal forward path, caused by sender_cpu & napi_id
skb fields being an union.

Bridge is another point where skb can be forwarded, so we need
the same cure.

Bug triggers if packet was received on a NIC using skb_mark_napi_id()

Fixes: 2bd82484bb4c ("xps: fix xps for stacked devices")
Signed-off-by: Eric Dumazet 
Reported-by: Bob Liu 
Tested-by: Bob Liu 
Signed-off-by: David S. Miller

netfilter: Pass socket pointer down through okfn().

2015-04-07T19:25:55+00:00

On the output paths in particular, we have to sometimes deal with two
socket contexts.  First, and usually skb->sk, is the local socket that
generated the frame.

And second, is potentially the socket used to control a tunneling
socket, such as one the encapsulates using UDP.

We do not want to disassociate skb->sk when encapsulating in order
to fix this, because that would break socket memory accounting.

The most extreme case where this can cause huge problems is an
AF_PACKET socket transmitting over a vxlan device.  We hit code
paths doing checks that assume they are dealing with an ipv4
socket, but are actually operating upon the AF_PACKET one.

Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next

2015-03-09T19:58:21+00:00

Pablo Neira Ayuso says:

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

The following patchset contains Netfilter updates for your net-next
tree. Basically, improvements for the packet rejection infrastructure,
deprecation of CLUSTERIP, cleanups for nf_tables and some untangling for
br_netfilter. More specifically they are:

1) Send packet to reset flow if checksum is valid, from Florian Westphal.

2) Fix nf_tables reject bridge from the input chain, also from Florian.

3) Deprecate the CLUSTERIP target, the cluster match supersedes it in
   functionality and it's known to have problems.

4) A couple of cleanups for nf_tables rule tracing infrastructure, from
   Patrick McHardy.

5) Another cleanup to place transaction declarations at the bottom of
   nf_tables.h, also from Patrick.

6) Consolidate Kconfig dependencies wrt. NF_TABLES.

7) Limit table names to 32 bytes in nf_tables.

8) mac header copying in bridge netfilter is already required when
   calling ip_fragment(), from Florian Westphal.

9) move nf_bridge_update_protocol() to br_netfilter.c, also from
   Florian.

10) Small refactor in br_netfilter in the transmission path, again from
    Florian.

11) Move br_nf_pre_routing_finish_bridge_slow() to br_netfilter.
====================

Signed-off-by: David S. Miller

bridge: move mac header copying into br_netfilter

2015-03-09T12:20:48+00:00

The mac header only has to be copied back into the skb for
fragments generated by ip_fragment(), which only happens
for bridge forwarded packets with nf-call-iptables=1 && active nf_defrag.

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

bridge: Extend Proxy ARP design to allow optional rules for Wi-Fi

2015-03-05T19:52:23+00:00

This extends the design in commit 958501163ddd ("bridge: Add support for
IEEE 802.11 Proxy ARP") with optional set of rules that are needed to
meet the IEEE 802.11 and Hotspot 2.0 requirements for ProxyARP. The
previously added BR_PROXYARP behavior is left as-is and a new
BR_PROXYARP_WIFI alternative is added so that this behavior can be
configured from user space when required.

In addition, this enables proxyarp functionality for unicast ARP
requests for both BR_PROXYARP and BR_PROXYARP_WIFI since it is possible
to use unicast as well as broadcast for these frames.

The key differences in functionality:

BR_PROXYARP:
- uses the flag on the bridge port on which the request frame was
  received to determine whether to reply
- block bridge port flooding completely on ports that enable proxy ARP

BR_PROXYARP_WIFI:
- uses the flag on the bridge port to which the target device of the
  request belongs
- block bridge port flooding selectively based on whether the proxyarp
  functionality replied

Signed-off-by: Jouni Malinen 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2014-11-01T18:53:27+00:00

Conflicts:
	drivers/net/phy/marvell.c

Simple overlapping changes in drivers/net/phy/marvell.c

Signed-off-by: David S. Miller

netfilter: nft_reject_bridge: don't use IP stack to reject traffic

2014-10-31T11:50:08+00:00

If the packet is received via the bridge stack, this cannot reject
packets from the IP stack.

This adds functions to build the reject packet and send it from the
bridge stack. Comments and assumptions on this patch:

1) Validate the IPv4 and IPv6 headers before further processing,
   given that the packet comes from the bridge stack, we cannot assume
   they are clean. Truncated packets are dropped, we follow similar
   approach in the existing iptables match/target extensions that need
   to inspect layer 4 headers that is not available. This also includes
   packets that are directed to multicast and broadcast ethernet
   addresses.

2) br_deliver() is exported to inject the reject packet via
   bridge localout -> postrouting. So the approach is similar to what
   we already do in the iptables reject target. The reject packet is
   sent to the bridge port from which we have received the original
   packet.

3) The reject packet is forged based on the original packet. The TTL
   is set based on sysctl_ip_default_ttl for IPv4 and per-net
   ipv6.devconf_all hoplimit for IPv6.

Signed-off-by: Pablo Neira Ayuso

bridge: Add support for IEEE 802.11 Proxy ARP

2014-10-27T23:02:04+00:00

This feature is defined in IEEE Std 802.11-2012, 10.23.13. It allows
the AP devices to keep track of the hardware-address-to-IP-address
mapping of the mobile devices within the WLAN network.

The AP will learn this mapping via observing DHCP, ARP, and NS/NA
frames. When a request for such information is made (i.e. ARP request,
Neighbor Solicitation), the AP will respond on behalf of the
associated mobile device. In the process of doing so, the AP will drop
the multicast request frame that was intended to go out to the wireless
medium.

It was recommended at the LKS workshop to do this implementation in
the bridge layer. vxlan.c is already doing something very similar.
The DHCP snooping code will be added to the userspace application
(hostapd) per the recommendation.

This RFC commit is only for IPv4. A similar approach in the bridge
layer will be taken for IPv6 as well.

Signed-off-by: Kyeyoon Park 
Signed-off-by: David S. Miller

netfilter: bridge: move br_netfilter out of the core

2014-09-26T16:42:31+00:00

Jesper reported that br_netfilter always registers the hooks since
this is part of the bridge core. This harms performance for people that
don't need this.

This patch modularizes br_netfilter so it can be rmmod'ed, thus,
the hooks can be unregistered. I think the bridge netfilter should have
been a separated module since the beginning, Patrick agreed on that.

Note that this is breaking compatibility for users that expect that
bridge netfilter is going to be available after explicitly 'modprobe
bridge' or via automatic load through brctl.

However, the damage can be easily undone by modprobing br_netfilter.
The bridge core also spots a message to provide a clue to people that
didn't notice that this has been deprecated.

On top of that, the plan is that nftables will not rely on this software
layer, but integrate the connection tracking into the bridge layer to
enable stateful filtering and NAT, which is was bridge netfilter users
seem to require.

This patch still keeps the fake_dst_ops in the bridge core, since this
is required by when the bridge port is initialized. So we can safely
modprobe/rmmod br_netfilter anytime.

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