This is Linux bridge implementation of root port guard.
If BPDU is received from a leaf (edge) port, it should not
be elected as root port.
Why would you want to do this?
If using STP on a bridge and the downstream bridges are not fully
trusted; this prevents a hostile guest for rerouting traffic.
Why not just use netfilter?
Netfilter does not track of follow spanning tree decisions.
It would be difficult and error prone to try and mirror STP
resolution in netfilter module.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is Linux bridge implementation of STP protection
(Cisco BPDU guard/Juniper BPDU block). BPDU block disables
the bridge port if a STP BPDU packet is received.
Why would you want to do this?
If running Spanning Tree on bridge, hostile devices on the network
may send BPDU and cause network failure. Enabling bpdu block
will detect and stop this.
How to recover the port?
The port will be restarted if link is brought down, or
removed and reattached. For example:
# ip li set dev eth0 down; ip li set dev eth0 up
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Expose bridge port parameter over netlink. By switching to a nested
message, this can be used for other bridge parameters.
This changes IFLA_PROTINFO attribute from one byte to a full nested
set of attributes. This is safe for application interface because the
old message used IFLA_PROTINFO and new one uses
IFLA_PROTINFO | NLA_F_NESTED.
The code adapts to old format requests, and therefore stays
compatible with user mode RSTP daemon. Since the type field
for nested and unnested attributes are different, and the old
code in libnetlink doesn't do the mask, it is also safe to use
with old versions of bridge monitor command.
Note: although mode is only a boolean, treating it as a
full byte since in the future someone will probably want to add more
values (like macvlan has).
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hardware switches may support enabling and disabling the
loopback switch which puts the device in a VEPA mode defined
in the IEEE 802.1Qbg specification. In this mode frames are
not switched in the hardware but sent directly to the switch.
SR-IOV capable NICs will likely support this mode I am
aware of at least two such devices. Also I am told (but don't
have any of this hardware available) that there are devices
that only support VEPA modes. In these cases it is important
at a minimum to be able to query these attributes.
This patch adds an additional IFLA_BRIDGE_MODE attribute that can be
set and dumped via the PF_BRIDGE:{SET|GET}LINK operations. Also
anticipating bridge attributes that may be common for both embedded
bridges and software bridges this adds a flags attribute
IFLA_BRIDGE_FLAGS currently used to determine if the command or event
is being generated to/from an embedded bridge or software bridge.
Finally, the event generation is pulled out of the bridge module and
into rtnetlink proper.
For example using the macvlan driver in VEPA mode on top of
an embedded switch requires putting the embedded switch into
a VEPA mode to get the expected results.
-------- --------
| VEPA | | VEPA | <-- macvlan vepa edge relays
-------- --------
| |
| |
------------------
| VEPA | <-- embedded switch in NIC
------------------
|
|
-------------------
| external switch | <-- shiny new physical
------------------- switch with VEPA support
A packet sent from the macvlan VEPA at the top could be
loopbacked on the embedded switch and never seen by the
external switch. So in order for this to work the embedded
switch needs to be set in the VEPA state via the above
described commands.
By making these attributes nested in IFLA_AF_SPEC we allow
future extensions to be made as needed.
CC: Lennert Buytenhek <buytenh@wantstofly.org>
CC: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PF_BRIDGE:RTM_{GET|SET}LINK nlmsg family and type are
currently embedded in the ./net/bridge module. This prohibits
them from being used by other bridging devices. One example
of this being hardware that has embedded bridging components.
In order to use these nlmsg types more generically this patch
adds two net_device_ops hooks. One to set link bridge attributes
and another to dump the current bride attributes.
ndo_bridge_setlink()
ndo_bridge_getlink()
CC: Lennert Buytenhek <buytenh@wantstofly.org>
CC: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is a frequent mistake to confuse the netlink port identifier with a
process identifier. Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.
I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.
I have successfully built an allyesconfig kernel with this change.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This ensures that bridges created with brctl(8) or ioctl(2) directly
also carry IFLA_LINKINFO when dumped over netlink. This also allows
to create a bridge with ioctl(2) and delete it with RTM_DELLINK.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds two new flags NTF_MASTER and NTF_SELF that can
now be used to specify where PF_BRIDGE netlink commands should
be sent. NTF_MASTER sends the commands to the 'dev->master'
device for parsing. Typically this will be the linux net/bridge,
or open-vswitch devices. Also without any flags set the command
will be handled by the master device as well so that current user
space tools continue to work as expected.
The NTF_SELF flag will push the PF_BRIDGE commands to the
device. In the basic example below the commands are then parsed
and programmed in the embedded bridge.
Note if both NTF_SELF and NTF_MASTER bits are set then the
command will be sent to both 'dev->master' and 'dev' this allows
user space to easily keep the embedded bridge and software bridge
in sync.
There is a slight complication in the case with both flags set
when an error occurs. To resolve this the rtnl handler clears
the NTF_ flag in the netlink ack to indicate which sets completed
successfully. The add/del handlers will abort as soon as any
error occurs.
To support this new net device ops were added to call into
the device and the existing bridging code was refactored
to use these. There should be no required changes in user space
to support the current bridge behavior.
A basic setup with a SR-IOV enabled NIC looks like this,
veth0 veth2
| |
------------
| bridge0 | <---- software bridging
------------
/
/
ethx.y ethx
VF PF
\ \ <---- propagate FDB entries to HW
\ \
--------------------
| Embedded Bridge | <---- hardware offloaded switching
--------------------
In this case the embedded bridge must be managed to allow 'veth0'
to communicate with 'ethx.y' correctly. At present drivers managing
the embedded bridge either send frames onto the network which
then get dropped by the switch OR the embedded bridge will flood
these frames. With this patch we have a mechanism to manage the
embedded bridge correctly from user space. This example is specific
to SR-IOV but replacing the VF with another PF or dropping this
into the DSA framework generates similar management issues.
Examples session using the 'br'[1] tool to add, dump and then
delete a mac address with a new "embedded" option and enabled
ixgbe driver:
# br fdb add 22:35:19:ac:60:59 dev eth3
# br fdb
port mac addr flags
veth0 22:35:19:ac:60:58 static
veth0 9a:5f:81:f7:f6:ec local
eth3 00:1b:21:55:23:59 local
eth3 22:35:19:ac:60:59 static
veth0 22:35:19:ac:60:57 static
#br fdb add 22:35:19:ac:60:59 embedded dev eth3
#br fdb
port mac addr flags
veth0 22:35:19:ac:60:58 static
veth0 9a:5f:81:f7:f6:ec local
eth3 00:1b:21:55:23:59 local
eth3 22:35:19:ac:60:59 static
veth0 22:35:19:ac:60:57 static
eth3 22:35:19:ac:60:59 local embedded
#br fdb del 22:35:19:ac:60:59 embedded dev eth3
I added a couple lines to 'br' to set the flags correctly is all. It
is my opinion that the merit of this patch is now embedded and SW
bridges can both be modeled correctly in user space using very nearly
the same message passing.
[1] 'br' tool was published as an RFC here and will be renamed 'bridge'
http://patchwork.ozlabs.org/patch/117664/
Thanks to Jamal Hadi Salim, Stephen Hemminger and Ben Hutchings for
valuable feedback, suggestions, and review.
v2: fixed api descriptions and error case with both NTF_SELF and
NTF_MASTER set plus updated patch description.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use of "unsigned int" is preferred to bare "unsigned" in net tree.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.
Signed-off-by: David S. Miller <davem@davemloft.net>
When in user-stp mode, bridge master do not follow state of its slaves, so
after the following sequence of events it can stuck forever in no-carrier
state:
1) turn stp off
2) put all slaves down - master device will follow their state and also go in
no-carrier state
3) turn stp on with bridge-stp script returning 0 (go to the user-stp mode)
Now bridge master won't follow slaves' state and will never reach running
state.
This patch solves the problem by making user-stp and kernel-stp behavior
similar regarding master following slaves' states.
Signed-off-by: Vitalii Demianets <vitas@nppfactor.kiev.ua>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Need to cleanup bridge device timers and ports when being bridge
device is being removed via netlink.
This fixes the problem of observed when doing:
ip link add br0 type bridge
ip link set dev eth1 master br0
ip link set br0 up
ip link del br0
which would cause br0 to hang in unregister_netdev because
of leftover reference count.
Reported-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When STP changes state of interface need to send a new link
message to reflect that change.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The message size allocated for rtnl ifinfo dumps was limited to
a single page. This is not enough for additional interface info
available with devices that support SR-IOV and caused a bug in
which VF info would not be displayed if more than approximately
40 VFs were created per interface.
Implement a new function pointer for the rtnl_register service that will
calculate the amount of data required for the ifinfo dump and allocate
enough data to satisfy the request.
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Four years ago, Patrick made a change to hold rtnl mutex during netlink
dump callbacks.
I believe it was a wrong move. This slows down concurrent dumps, making
good old /proc/net/ files faster than rtnetlink in some situations.
This occurred to me because one "ip link show dev ..." was _very_ slow
on a workload adding/removing network devices in background.
All dump callbacks are able to use RCU locking now, so this patch does
roughly a revert of commits :
1c2d670f36 : [RTNETLINK]: Hold rtnl_mutex during netlink dump callbacks
6313c1e099 : [RTNETLINK]: Remove unnecessary locking in dump callbacks
This let writers fight for rtnl mutex and readers going full speed.
It also takes care of phonet : phonet_route_get() is now called from rcu
read section. I renamed it to phonet_route_get_rcu()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add netlink device ops to allow creating bridge device via netlink.
This works in a manner similar to vlan, macvlan and bonding.
Example:
# ip link add link dev br0 type bridge
# ip link del dev br0
The change required rearranging initializtion code to deal with
being called by create link. Most of the initialization happens
in br_dev_setup, but allocation of stats is done in ndo_init callback
to deal with allocation failure. Sysfs setup has to wait until
after the network device kobject is registered.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use RTM_NEWNEIGH and RTM_DELNEIGH to allow updating of entries
in bridge forwarding table. This allows manipulating static entries
which is not possible with existing tools.
Example (using bridge extensions to iproute2)
# br fdb add 00:02:03:04:05:06 dev eth0
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This allows applications to query and monitor bridge forwarding
table in the same method used for neighbor table. The forward table
entries are returned in same structure format as used by the ioctl.
If more information is desired in future, the netlink method is
extensible.
Example (using bridge extensions to iproute2)
# br monitor
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
br_port_get() renamed to br_port_get_rtnl() to make clear RTNL is held.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The macro br_port_exists() is not enough protection when only
RCU is being used. There is a tiny race where other CPU has cleared port
handler hook, but is bridge port flag might still be set.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Register net_bridge_port pointer as rx_handler data pointer. As br_port is
removed from struct net_device, another netdev priv_flag is added to indicate
the device serves as a bridge port. Also rcuized pointers are now correctly
dereferenced in br_fdb.c and in netfilter parts.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use one set of macro's for all bridge messages.
Note: can't use netdev_XXX macro's because bridge is purely
virtual and has no device parent.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
This patch changes the return value of nlmsg_notify() as follows:
If NETLINK_BROADCAST_ERROR is set by any of the listeners and
an error in the delivery happened, return the broadcast error;
else if there are no listeners apart from the socket that
requested a change with the echo flag, return the result of the
unicast notification. Thus, with this patch, the unicast
notification is handled in the same way of a broadcast listener
that has set the NETLINK_BROADCAST_ERROR socket flag.
This patch is useful in case that the caller of nlmsg_notify()
wants to know the result of the delivery of a netlink notification
(including the broadcast delivery) and take any action in case
that the delivery failed. For example, ctnetlink can drop packets
if the event delivery failed to provide reliable logging and
state-synchronization at the cost of dropping packets.
This patch also modifies the rtnetlink code to ignore the return
value of rtnl_notify() in all callers. The function rtnl_notify()
(before this patch) returned the error of the unicast notification
which makes rtnl_set_sk_err() reports errors to all listeners. This
is not of any help since the origin of the change (the socket that
requested the echoing) notices the ENOBUFS error if the notification
fails and should resync itself.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bridge as netdevice doesn't cross netns boundaries.
Bridge ports and bridge itself live in same netns.
Notifiers are fixed.
netns propagated from userspace socket for setup and teardown.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Stephen Hemminger <shemming@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce per-sock inlines: sock_net(), sock_net_set()
and per-inet_timewait_sock inlines: twsk_net(), twsk_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
After this patch none of the netlink callback support anything
except the initial network namespace but the rtnetlink infrastructure
now handles multiple network namespaces.
Changes from v2:
- IPv6 addrlabel processing
Changes from v1:
- no need for special rtnl_unlock handling
- fixed IPv6 ndisc
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Before I can enable rtnetlink to work in all network namespaces I need
to be certain that something won't break. So this patch deliberately
disables all of the rtnletlink methods in everything except the
initial network namespace. After the methods have been audited this
extra check can be disabled.
Changes from v1:
- added IPv6 addrlabel protection
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch makes most of the generic device layer network
namespace safe. This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables. The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl
were modified to take a network namespace argument, and
deal with it.
vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.
So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces. The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace. This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.
For now the ifindex generator is left global.
Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.
At the same time there are assumptions in the network stack
that the ifindex of a network device won't change. Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cleanup of dev_base list use, with the aim to simplify making device
list per-namespace. In almost every occasion, use of dev_base variable
and dev->next pointer could be easily replaced by for_each_netdev
loop. A few most complicated places were converted to using
first_netdev()/next_netdev().
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since we're now holding the rtnl during the entire dump operation, we can
remove additional locking for rtnl protected data. This patch does that
for all simple cases (dev_base_lock for dev_base walking, RCU protection
for FIB rule dumping).
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patchset based on work by Aji_Srinivas@emc.com provides allows
spanning tree to be controled from userspace. Like hotplug, it
uses call_usermodehelper when spanning tree is enabled so there
is no visible API change. If call to start usermode STP fails
it falls back to existing kernel STP.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Currently netlink users BUG when the allocated skb for an event
notification is undersized. While this is certainly a kernel bug,
its not critical and crashing the kernel is too drastic, especially
when considering that these errors have appeared multiple times in
the past and it BUGs even if no listeners are present.
This patch replaces BUG by WARN_ON and changes the notification
functions to inform potential listeners of undersized allocations
using a unique error code (EMSGSIZE).
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Removes dependency on buggy rta_buf, fixes a memory corruption bug due to
a unvalidated netlink attribute, and simplifies the code.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Account for the netlink message header size directly in nlmsg_new()
instead of relying on the caller calculate it correctly.
Replaces error handling of message construction functions when
constructing notifications with bug traps since a failure implies
a bug in calculating the size of the skb.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix code that passes back netlink status messages about
bridge changes. Submitted by Aji_Srinivas@emc.com
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix for inability of br_dump_ifinfo to handle non-zero start index:
loop index never increases when entered with non-zero start.
Spotted by Kirill Korotaev.
Signed-off-by: Andrey Savochkin <saw@swsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add basic netlink support to the Ethernet bridge. Including:
* dump interfaces in bridges
* monitor link status changes
* change state of bridge port
For some demo programs see:
http://developer.osdl.org/shemminger/prototypes/brnl.tar.gz
These are to allow building a daemon that does alternative
implementations of Spanning Tree Protocol.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>