Currently the functionality to untag traffic on input resides
as part of the vlan module and is build only when VLAN support
is enabled in the kernel.  When VLAN is disabled, the function
vlan_untag() turns into a stub and doesn't really untag the
packets.  This seems to create an interesting interaction
between VMs supporting checksum offloading and some network drivers.

There are some drivers that do not allow the user to change
tx-vlan-offload feature of the driver.  These drivers also seem
to assume that any VLAN-tagged traffic they transmit will
have the vlan information in the vlan_tci and not in the vlan
header already in the skb.  When transmitting skbs that already
have tagged data with partial checksum set, the checksum doesn't
appear to be updated correctly by the card thus resulting in a
failure to establish TCP connections.

The following is a packet trace taken on the receiver where a
sender is a VM with a VLAN configued.  The host VM is running on
doest not have VLAN support and the outging interface on the
host is tg3:
10:12:43.503055 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q
(0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27243,
offset 0, flags [DF], proto TCP (6), length 60)
    10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect
-> 0x48d9), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val
4294837885 ecr 0,nop,wscale 7], length 0
10:12:44.505556 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q
(0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27244,
offset 0, flags [DF], proto TCP (6), length 60)
    10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect
-> 0x44ee), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val
4294838888 ecr 0,nop,wscale 7], length 0

This connection finally times out.

I've only access to the TG3 hardware in this configuration thus have
only tested this with TG3 driver.  There are a lot of other drivers
that do not permit user changes to vlan acceleration features, and
I don't know if they all suffere from a similar issue.

The patch attempt to fix this another way.  It moves the vlan header
stipping code out of the vlan module and always builds it into the
kernel network core.  This way, even if vlan is not supported on
a virtualizatoin host, the virtual machines running on top of such
host will still work with VLANs enabled.

CC: Patrick McHardy <kaber@trash.net>
CC: Nithin Nayak Sujir <nsujir@broadcom.com>
CC: Michael Chan <mchan@broadcom.com>
CC: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NVladislav Yasevich <vyasevic@redhat.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Eric Dumazet reports that getsockopt() or setsockopt() sometimes
returns -EINTR instead of -ENOPROTOOPT, causing headaches to
application developers.

This patch replaces all the mutex_lock_interruptible() by mutex_lock()
in the netfilter tree, as there is no reason we should sleep for a
long time there.
Reported-by: NEric Dumazet <edumazet@google.com>
Suggested-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Acked-by: NJulian Anastasov <ja@ssi.bg>

All other add functions for lists have the new item as first argument
and the position where it is added as second argument.  This was changed
for no good reason in this function and makes using it unnecessary
confusing.

The name was changed to hlist_add_behind() to cause unconverted code to
generate a compile error instead of using the wrong parameter order.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NKen Helias <kenhelias@firemail.de>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>	[intel driver bits]
Cc: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Now bridge ports can be non-promiscuous, vlan_vid_add() is no longer an
unnecessary operation.
Signed-off-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 6cbdceeb
    bridge: Dump vlan information from a bridge port
introduced a comment in an attempt to explain the
code logic. The comment is unfinished so it confuses more
than it explains, remove it.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

An FDB entry with vlan_id 0 doesn't mean it is used in vlan 0, but used when
vlan_filtering is disabled.

There is inconsistency around NDA_VLAN whose payload is 0 - even if we add
an entry by RTM_NEWNEIGH without any NDA_VLAN, and even though adding an
entry with NDA_VLAN 0 is prohibited, we get an entry with NDA_VLAN 0 by
RTM_GETNEIGH.

Dumping an FDB entry with vlan_id 0 shouldn't include NDA_VLAN.
Signed-off-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ulog targets were recently killed. A few references to the Kconfig
macros CONFIG_IP_NF_TARGET_ULOG and CONFIG_BRIDGE_EBT_ULOG were left
untouched. Kill these too.
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

So you can reject IPv4 and IPv6 packets from bridge tables. If the ether
proto is now known, default on dropping the packet instead.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert
all users to pass NET_NAME_UNKNOWN.

Coccinelle patch:

@@
expression sizeof_priv, name, setup, txqs, rxqs, count;
@@

(
-alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs)
+alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs)
|
-alloc_netdev_mq(sizeof_priv, name, setup, count)
+alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count)
|
-alloc_netdev(sizeof_priv, name, setup)
+alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup)
)

v9: move comments here from the wrong commit
Signed-off-by: NTom Gundersen <teg@jklm.no>
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Actually better than brctl showmacs because we can filter by bridge
port in the kernel.
The current bridge netlink interface doesnt scale when you have many
bridges each with large fdbs or even bridges with many bridge ports

And now for the science non-fiction novel you have all been
waiting for..

//lets see what bridge ports we have
root@moja-1:/configs/may30-iprt/bridge# ./bridge link show
8: eth1 state DOWN : <BROADCAST,MULTICAST> mtu 1500 master br0 state
disabled priority 32 cost 19
17: sw1-p1 state DOWN : <BROADCAST,NOARP> mtu 1500 master br0 state
disabled priority 32 cost 100

// show all..
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show
33:33:00:00:00:01 dev bond0 self permanent
33:33:00:00:00:01 dev dummy0 self permanent
33:33:00:00:00:01 dev ifb0 self permanent
33:33:00:00:00:01 dev ifb1 self permanent
33:33:00:00:00:01 dev eth0 self permanent
01:00:5e:00:00:01 dev eth0 self permanent
33:33:ff:22:01:01 dev eth0 self permanent
02:00:00:12:01:02 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:05 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:07 dev eth1 self permanent
33:33:00:00:00:01 dev eth1 self permanent
33:33:00:00:00:01 dev gretap0 self permanent
da:ac:46:27:d9:53 dev sw1-p1 vlan 0 master br0 permanent
33:33:00:00:00:01 dev sw1-p1 self permanent

//filter by bridge
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show br br0
02:00:00:12:01:02 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:05 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:07 dev eth1 self permanent
33:33:00:00:00:01 dev eth1 self permanent
da:ac:46:27:d9:53 dev sw1-p1 vlan 0 master br0 permanent
33:33:00:00:00:01 dev sw1-p1 self permanent

// bridge sw1 has no ports attached..
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show br sw1

//filter by port
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show brport eth1
02:00:00:12:01:02 vlan 0 master br0 permanent
00:17:42:8a:b4:05 vlan 0 master br0 permanent
00:17:42:8a:b4:07 self permanent
33:33:00:00:00:01 self permanent

// filter by port + bridge
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show br br0 brport
sw1-p1
da:ac:46:27:d9:53 vlan 0 master br0 permanent
33:33:00:00:00:01 self permanent

// for shits and giggles (as they say in New Brunswick), lets
// change the mac that br0 uses
// Note: a magical fdb entry with no brport is added ...
root@moja-1:/configs/may30-iprt/bridge# ip link set dev br0 address
02:00:00:12:01:04

// lets see if we can see the unicorn ..
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show
33:33:00:00:00:01 dev bond0 self permanent
33:33:00:00:00:01 dev dummy0 self permanent
33:33:00:00:00:01 dev ifb0 self permanent
33:33:00:00:00:01 dev ifb1 self permanent
33:33:00:00:00:01 dev eth0 self permanent
01:00:5e:00:00:01 dev eth0 self permanent
33:33:ff:22:01:01 dev eth0 self permanent
02:00:00:12:01:02 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:05 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:07 dev eth1 self permanent
33:33:00:00:00:01 dev eth1 self permanent
33:33:00:00:00:01 dev gretap0 self permanent
02:00:00:12:01:04 dev br0 vlan 0 master br0 permanent <=== there it is
da:ac:46:27:d9:53 dev sw1-p1 vlan 0 master br0 permanent
33:33:00:00:00:01 dev sw1-p1 self permanent

//can we see it if we filter by bridge?
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show br br0
02:00:00:12:01:02 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:05 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:07 dev eth1 self permanent
33:33:00:00:00:01 dev eth1 self permanent
02:00:00:12:01:04 dev br0 vlan 0 master br0 permanent <=== there it is
da:ac:46:27:d9:53 dev sw1-p1 vlan 0 master br0 permanent
33:33:00:00:00:01 dev sw1-p1 self permanent
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Dumping a bridge fdb dumps every fdb entry
held. With this change we are going to filter
on selected bridge port.
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With this patch other modules are able to ask the bridge whether an
IGMP or MLD querier exists on the according, bridged link layer.

Multicast snooping can only be performed if a valid, selected querier
exists on a link.

Just like the bridge only enables its multicast snooping if a querier
exists, e.g. batman-adv too can only activate its multicast
snooping in bridged scenarios if a querier is present.

For instance this export avoids having to reimplement IGMP/MLD
querier message snooping and parsing in e.g. batman-adv, when
multicast optimizations for bridged scenarios are added in the
future.
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This adds the generic plain text packet loggger for bridged packets.
It routes the logging message to the real protocol packet logger.
I decided not to refactor the ebt_log code for two reasons:

1) The ebt_log output is not consistent with the IPv4 and IPv6
   Netfilter packet loggers. The output is different for no good
   reason and it adds redundant code to handle packet logging.

2) To avoid breaking backward compatibility for applications
   outthere that are parsing the specific ebt_log output, the ebt_log
   output has been left as is. So only nftables will use the new
   consistent logging format for logged bridged packets.

More decisions coming in this patch:

1) This also removes ebt_log as default logger for bridged packets.
   Thus, nf_log_packet() routes packet to this new packet logger
   instead. This doesn't break backward compatibility since
   nf_log_packet() is not used to log packets in plain text format
   from anywhere in the ebtables/netfilter bridge code.

2) The new bridge packet logger also performs a lazy request to
   register the real IPv4, ARP and IPv6 netfilter packet loggers.
   If the real protocol logger is no available (not compiled or the
   module is not available in the system, not packet logging happens.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Now that legacy ulog targets are not available anymore in the tree, we
can have up to two possible loggers:

1) The plain text logging via kernel logging ring.
2) The nfnetlink_log infrastructure which delivers log messages
   to userspace.

This patch replaces the list of loggers by an array of two pointers
per family for each possible logger and it also introduces a new field
to the nf_logger structure which indicates the position in the logger
array (based on the logger type).

This prepares a follow up patch that consolidates the nf_log_packet()
interface by allowing to specify the logger as parameter.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This has been marked as deprecated for quite some time and the NFLOG
target replacement has been also available since 2006.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

use list_for_each_entry_continue_reverse to rollback in fdb_add_hw
when add address failed
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some fields in "struct net_bridge" aren't available when compiling the
kernel without IPv6 support. Therefore adding a check/macro to skip the
complaining code sections in that case.

Introduced by 2cd41431
("bridge: memorize and export selected IGMP/MLD querier port")
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

"New smatch warnings:
  net/bridge/br_multicast.c:1368 br_ip6_multicast_query() error:
    we previously assumed 'group' could be null (see line 1349)"

In the rare (sort of broken) case of a query having a Maximum
Response Delay of zero, we could create a potential null pointer
dereference.

Fixing this by skipping the multicast specific MLD Query parsing again
if no multicast group address is available.

Introduced by dc4eb53a
("bridge: adhere to querier election mechanism specified by RFCs")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This enables us to change the vlan protocol for vlan filtering.
We come to be able to filter frames on the basis of 802.1ad vlan tags
through a bridge.

This also changes br->group_addr if it has not been set by user.
This is needed for an 802.1ad bridge.
(See IEEE 802.1Q-2011 8.13.5.)

Furthermore, this sets br->group_fwd_mask_required so that an 802.1ad
bridge can forward the Nearest Customer Bridge group addresses except
for br->group_addr, which should be passed to higher layer.

To change the vlan protocol, write a protocol in sysfs:
# echo 0x88a8 > /sys/class/net/br0/bridge/vlan_protocol
Signed-off-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If a bridge is an 802.1ad bridge, it must forward another bridge group
addresses (the Nearest Customer Bridge group addresses).
(For details, see IEEE 802.1Q-2011 8.6.3.)

As user might not want group_fwd_mask to be modified by enabling 802.1ad,
introduce a new mask, group_fwd_mask_required, which indicates addresses
the bridge wants to forward. This will be set by enabling 802.1ad.
Signed-off-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This enables a bridge to have vlan protocol informantion and allows vlan
tag manipulation (retrieve, insert and remove tags) according to the vlan
protocol.
Signed-off-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Bridge device doesn't need to embed S-tag into skb->data.
Signed-off-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adding bridge support to the batman-adv multicast optimization requires
batman-adv knowing about the existence of bridged-in IGMP/MLD queriers
to be able to reliably serve any multicast listener behind this same
bridge.
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With this new, exported function br_multicast_list_adjacent(net_dev) a
list of IPv4/6 addresses is returned. This list contains all multicast
addresses sensed by the bridge multicast snooping feature on all bridge
ports of the bridge interface of net_dev, excluding addresses from the
specified net_device itself.

Adding bridge support to the batman-adv multicast optimization requires
batman-adv knowing about the existence of bridged-in multicast
listeners to be able to reliably serve them with multicast packets.
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

MLDv1 (RFC2710 section 6), MLDv2 (RFC3810 section 7.6.2), IGMPv2
(RFC2236 section 3) and IGMPv3 (RFC3376 section 6.6.2) specify that the
querier with lowest source address shall become the selected
querier.

So far the bridge stopped its querier as soon as it heard another
querier regardless of its source address. This results in the "wrong"
querier potentially becoming the active querier or a potential,
unnecessary querying delay.

With this patch the bridge memorizes the source address of the currently
selected querier and ignores queries from queriers with a higher source
address than the currently selected one. This slight optimization is
supposed to make it more RFC compliant (but is rather uncritical and
therefore probably not necessary to be queued for stable kernels).
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current naming of these two structs is very random, in that
reversing their naming would not make any semantical difference.

This patch tries to make the naming less confusing by giving them a more
specific, distinguishable naming.

This is also useful for the upcoming patches reintroducing the
"struct bridge_mcast_querier" but for storing information about the
selected querier (no matter if our own or a foreign querier).
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

br_manage_promisc() incorrectly expects br_auto_port() to return only 0
or 1, while it actually returns flags, i.e., a subset of BR_AUTO_MASK.
Signed-off-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

(This patch was previously posted as RFC at
http://patchwork.ozlabs.org/patch/352677/)

This patch adds NDA_MASTER attribute to neighbour attributes enum for
bridge/master ifindex. And adds NDA_MASTER to bridge fdb notify msgs.

Today bridge fdb notifications dont contain bridge information.
Userspace can derive it from the port information in the fdb
notification. However this is tricky in some scenarious.

Example, bridge port delete notification comes before bridge fdb
delete notifications. And we have seen problems in userspace
when using libnl where, the bridge fdb delete notification handling code
does not understand which bridge this fdb entry is part of because
the bridge and port association has already been deleted.
And these notifications (port membership and fdb) are generated on
separate rtnl groups.

Fixing the order of notifications could possibly solve the problem
for some cases (I can submit a separate patch for that).

This patch chooses to add NDA_MASTER to bridge fdb notify msgs
because it not only solves the problem described above, but also helps
userspace avoid another lookup into link msgs to derive the master index.
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

br_handle_local_finish() is allowing us to insert an FDB entry with
disallowed vlan. For example, when port 1 and 2 are communicating in
vlan 10, and even if vlan 10 is disallowed on port 3, port 3 can
interfere with their communication by spoofed src mac address with
vlan id 10.

Note: Even if it is judged that a frame should not be learned, it should
not be dropped because it is destined for not forwarding layer but higher
layer. See IEEE 802.1Q-2011 8.13.10.
Signed-off-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: NVlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There has been a number incidents recently where customers running KVM have
reported that VM hosts on different Hypervisors are unreachable. Based on
pcap traces we found that the bridge was broadcasting the ARP request out
onto the network. However some NICs have an inbuilt switch which on occasions
were broadcasting the VMs ARP request back through the physical NIC on the
Hypervisor. This resulted in the bridge changing ports and incorrectly learning
that the VMs mac address was external. As a result the ARP reply was directed
back onto the external network and VM never updated it's ARP cache. This patch
will notify the bridge command, after a fdb has been updated to identify such
port toggling.
Signed-off-by: NJon Maxwell <jmaxwell37@gmail.com>
Reviewed-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As commit 2796d0c6 ("bridge: Automatically manage port
promiscuous mode."), make the add_if use dev_set_allmulti
instead of dev_set_promiscuous, so when add_if failed, we
should do dev_set_allmulti(dev, -1).
Signed-off-by: NWang Weidong <wangweidong1@huawei.com>
Reviewed-by: NAmos Kong <akong@redhat.com>
Acked-by: NVlad Yasevich <vyasevic@redhat.com>
Acked-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Before f5efc696 ("netfilter: nf_tables: Add meta expression key for
bridge interface name"), the entire net/bridge/netfilter/ directory
depended on BRIDGE_NF_EBTABLES, ie. on ebtables. However, that
directory already contained the nf_tables bridge extension that
we should allow to compile separately. In f5efc696, we tried to
generalize this by using CONFIG_BRIDGE_NETFILTER which was not a good
idea since this option already existed and it is dedicated to enable
the Netfilter bridge IP/ARP filtering.

Let's try to fix this mess by:

1) making net/bridge/netfilter/ dependent on the toplevel
   CONFIG_NETFILTER option, just like we do with the net/netfilter and
   net/ipv{4,6}/netfilter/ directories.

2) Changing 'selects' to 'depends on' NETFILTER_XTABLES for
   BRIDGE_NF_EBTABLES. I believe this problem was already before
   f5efc696:

warning: (BRIDGE_NF_EBTABLES) selects NETFILTER_XTABLES which has
unmet direct dependencies (NET && INET && NETFILTER)

3) Fix ebtables/nf_tables bridge dependencies by making NF_TABLES_BRIDGE
   and BRIDGE_NF_EBTABLES dependent on BRIDGE and NETFILTER:

warning: (NF_TABLES_BRIDGE && BRIDGE_NF_EBTABLES) selects
BRIDGE_NETFILTER which has unmet direct dependencies (NET && BRIDGE &&
NETFILTER && INET && NETFILTER_ADVANCED)

net/built-in.o: In function `br_parse_ip_options':
br_netfilter.c:(.text+0x4a5ba): undefined reference to `ip_options_compile'
br_netfilter.c:(.text+0x4a5ed): undefined reference to `ip_options_rcv_srr'
net/built-in.o: In function `br_nf_pre_routing_finish':
br_netfilter.c:(.text+0x4a8a4): undefined reference to `ip_route_input_noref'
br_netfilter.c:(.text+0x4a987): undefined reference to `ip_route_output_flow'
make: *** [vmlinux] Error 1
Reported-by: NJim Davis <jim.epost@gmail.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Merge net/bridge/br_notify.c into net/bridge/br.c,
since it has only br_device_event() and br.c is small.

Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fix build when BRIDGE_VLAN_FILTERING is not set

Fixes: 2796d0c6 ("bridge: Automatically manage port promiscuous mode")
Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There exist configurations where the administrator or another management
entity has the foreknowledge of all the mac addresses of end systems
that are being bridged together.

In these environments, the administrator can statically configure known
addresses in the bridge FDB and disable flooding and learning on ports.
This makes it possible to turn off promiscuous mode on the interfaces
connected to the bridge.

Here is why disabling flooding and learning allows us to control
promiscuity:
 Consider port X.  All traffic coming into this port from outside the
bridge (ingress) will be either forwarded through other ports of the
bridge (egress) or dropped.  Forwarding (egress) is defined by FDB
entries and by flooding in the event that no FDB entry exists.
In the event that flooding is disabled, only FDB entries define
the egress.  Once learning is disabled, only static FDB entries
provided by a management entity define the egress.  If we provide
information from these static FDBs to the ingress port X, then we'll
be able to accept all traffic that can be successfully forwarded and
drop all the other traffic sooner without spending CPU cycles to
process it.
 Another way to define the above is as following equations:
    ingress = egress + drop
 expanding egress
    ingress = static FDB + learned FDB + flooding + drop
 disabling flooding and learning we a left with
    ingress = static FDB + drop

By adding addresses from the static FDB entries to the MAC address
filter of an ingress port X, we fully define what the bridge can
process without dropping and can thus turn off promiscuous mode,
thus dropping packets sooner.

There have been suggestions that we may want to allow learning
and update the filters with learned addresses as well.  This
would require mac-level authentication similar to 802.1x to
prevent attacks against the hw filters as they are limited
resource.

Additionally, if the user places the bridge device in promiscuous mode,
all ports are placed in promiscuous mode regardless of the changes
to flooding and learning.

Since the above functionality depends on full static configuration,
we have also require that vlan filtering be enabled to take
advantage of this.  The reason is that the bridge has to be
able to receive and process VLAN-tagged frames and the there
are only 2 ways to accomplish this right now: promiscuous mode
or vlan filtering.
Suggested-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NVlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a static fdb entry is created, add the mac address
from this fdb entry to any ports that are currently running
in non-promiscuous mode.  These ports need this data so that
they can receive traffic destined to these addresses.
By default ports start in promiscuous mode, so this feature
is disabled.
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NVlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce a BR_PROMISC per-port flag that will help us track if the
current port is supposed to be in promiscuous mode or not.  For now,
always start in promiscuous mode.
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NVlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add code that allows static fdb entires to be synced to the
hw list for a specified port.  This will be used later to
program ports that can function in non-promiscuous mode.
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NVlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

By default, ports on the bridge are capable of automatic
discovery of nodes located behind the port.  This is accomplished
via flooding of unknown traffic (BR_FLOOD) and learning the
mac addresses from these packets (BR_LEARNING).
If the above functionality is disabled by turning off these
flags, the port requires static configuration in the form
of static FDB entries to function properly.

This patch adds functionality to keep track of all ports
capable of automatic discovery.  This will later be used
to control promiscuity settings.
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NVlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>