Batman-adv could receive several payload broadcasts at the same time
that would trigger access to the broadcast seqno sliding window to
determine whether this is a new broadcast or not. If these incoming
broadcasts are accessing the sliding window simultaneously it could
be left in an inconsistent state. Therefore it is necessary to make
sure this access is atomic.
Reported-by: NLinus Lüssing <linus.luessing@web.de>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Reported-by: NLinus Lüssing <linus.luessing@saxnet.de>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

It might be possible that 2 threads access the same data in the same
rcu grace period. The first thread calls call_rcu() to decrement the
refcount and free the data while the second thread increases the
refcount to use the data. To avoid this race condition all refcount
operations have to be atomic.
Reported-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

bonding / alternating candidates need to be secured by rcu locks
as well. This patch therefore converts the bonding list
from a plain pointer list to a rcu securable lists and references
the bonding candidates.
Signed-off-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

types.h is included by main.h, which is included at the beginning of any
other c-file anyway. Therefore this commit removes those duplicate
inclussions.
Signed-off-by: NLinus Lüssing <linus.luessing@ascom.ch>
Signed-off-by: NSven Eckelmann <sven@narfation.org>

Signed-off-by: NSven Eckelmann <sven@narfation.org>

Signed-off-by: NSven Eckelmann <sven@narfation.org>

Some function parameters are obsolete now and can be removed.
Reported-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NSven Eckelmann <sven@narfation.org>

The routing algorithm must be able to decide if a fragment can be merged with
the missing part and still be passed to a forwarding interface. The fragments
can only differ by one byte in case that the original payload had an uneven
length. In that situation the sender has to inform all possible receivers that
the tail is one byte longer using the flag UNI_FRAG_LARGETAIL.

The combination of UNI_FRAG_LARGETAIL and UNI_FRAG_HEAD flag makes it possible
to calculate the correct length for even and uneven sized payloads.

The original formula missed to add the unicast header at all and forgot to
remove the fragment header of the second fragment. This made the results highly
unreliable and only useful for machines with large differences between the
configured MTUs.
Reported-by: NRussell Senior <russell@personaltelco.net>
Reported-by: NMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: NSven Eckelmann <sven@narfation.org>

B.A.T.M.A.N. (better approach to mobile ad-hoc networking) is a routing
protocol for multi-hop ad-hoc mesh networks. The networks may be wired or
wireless. See http://www.open-mesh.org/ for more information and user space
tools.
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

linux/etherdevice.h already provides functions to classify different
ethernet addresses. These inlineable functions should be used instead of
custom functions.

The check for multicast together with multicast can also be replaced
with a single test for multicast because for every ethernet address x
following is always true:

is_broadcast_ether_addr(x) => is_multicast_ether_addr(x)

or when looking more at the implementation:

(FF:FF:FF:FF:FF:FF == x) => [(01:00:00:00:00:00 & x) != 00:00:00:00:00:00]
Reported-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Via the /sys filesystem you can change the gateway mode of a node using
gw_mode. Adjustments to it can be done using gw_bandwidth for server
mode and gw_sel_class for client mode.
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
[sven.eckelmann@gmx.de: Rework on top of current version]
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

spin_lock_irqsave disables the IRQs and stores them inside the flags
provided by the caller. This is needed to protect a bottom half handler
or a user context critical section from being interrupted by an
interrupt handler which also tries to acquire the spinlock and locks
forever.

The linux device drivers will receive the packets inside an interrupt
handler and the network infrastructure will process them inside bottom
half. Thus batman-adv will only run in user context and bottom half
handlers. We can conclude that batman-adv doesn't share its own
spinlocks with real interrupt handlers.

This makes it possible to exchange the quite complex spin_lock_irqsave
with spin_lock_bh which only stops bottom halves from running on the
current cpu, but allows interrupt handlers to take over to keep the
interrupt latency low.
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The hash implementation is a complete implementation of a hash using
buckets as hash entries and overflow buckets attached to them.

The kernel already provides datastructures hlist_head and hlist_node
which can be used to implement an hash using lists as hash buckets. So
it is better to implement heavily used functionality on top of those
instead of providing a full hash implementation.

The rewrite changes the behavior of some functions slightly:
 * hash_add add elements to the front instead of the tail
 * hash_iterate doesn't provide pointer to access bucket->data directly,
   but it can be accessed using hlist_entry
Reported-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Function pointers cannot be inlined by a compiler and thus always has
the overhead of an call. hashdata_choose_cb's are one of the most often
called function pointers and its overhead must kept relative low.

As first step, every function which uses this function pointer takes it
as parameter instead of storing it inside the hash abstraction
structure.

This not generate any performance gain right now. The called functions
must also be able to be inlined by the calling functions to enable
inlining of the function pointer.
Reported-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Function pointers cannot be inlined by a compiler and thus always has
the overhead of an call. hashdata_compare_cb's are one of the most often
called function pointers and its overhead must kept relative low.

As first step, every function which uses this function pointer takes it
as parameter instead of storing it inside the hash abstraction
structure.

This not generate any performance gain right now. The called functions
must also be able to be inlined by the calling functions to enable
inlining of the function pointer.
Reported-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Both sysfs entries and variable names shall be as descriptive as
possible while not exceeding a certain length. This patch renames
bat_priv atomics to be equally descriptive with their according sysfs
entries.

Unifying sysfs and bat_priv atomic names also makes it easier to find
each others pendant.

The reduced ("type"-)information which was previously indicated with a
_enabled for booleans got substituted by a comment in bat_priv.

This patch has also been done in regards for the future BAT_ATTR_*
macros (they only need one name argument instead of a file and variable
name).
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

By connecting multiple batman-adv mesh nodes to the same ethernet
segment a loop can be created when the soft-interface is bridged
into that ethernet segment. A simple visualization of the loop
involving the most common case - a LAN as ethernet segment:

node1  <-- LAN  -->  node2
   |                   |
 wifi  <-- mesh -->  wifi

Packets from the LAN (e.g. ARP broadcasts) will circle forever from
node1 or node2 over the mesh back into the LAN.

This patch adds the functionality to detect other batman-adv nodes
connected to the LAN and select a 'gateway' to talk to the
non-batman-adv devices on this LAN. All traffic from and to the mesh
will be handled by this gateway to avoid the loop. OGMs received via
the soft-interface are interpreted as 'port announcements' to locate
potential batman-adv nodes. The patch can also deal with vlans on
top of batX and offers a list of LAN neighbors via debugfs.
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
[sven.eckelmann@gmx.de: Rework on top of current version]
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NAndreas Langer <an.langer@gmx.de>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

If a packet is too big to be forwarded over an interface it will be
fragmented on-the-fly (if fragmentation is enabled).
Signed-off-by: NAndreas Langer <an.langer@gmx.de>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Callers should check the if the received packet is for us before it
calls route_unicast_packet.
Signed-off-by: NAndreas Langer <an.langer@gmx.de>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NAndreas Langer <an.langer@gmx.de>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NAndreas Langer <an.langer@gmx.de>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This reverts commit 5712dc7f.

Turns out the batman maintainers didn't like the implementation of it,
and the original author was going to rework it to meet their approval,
and I applied it without fully realizing all of this.

My fault.

Cc: Marek Lindner <lindner_marek@yahoo.de>
Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

55d1666b521cbed95924c8d4775fe272c103f08c incidentally disabled bonding
of packets first entering the mesh along with also disabling interface
alternating regardless of where the packet came from. This re-enables
these options.
Signed-off-by: NChris Lang <clang@gateworks.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Replace custom ethernet address check functions by calls to the helpers
in linux/etherdevice.h

In one case where the address was tested for broadcast and multicast
address, the broadcast address check can be omitted as broadcast is also
a multicast address.

The patch is only compile-tested.

Cc: Marek Lindner <lindner_marek@yahoo.de>
Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Since all *printf() methods in the kernel understand '%pM' modifier the
conversion to the string is useless beforehand.

Additionally this patch decreases batman_if structure by 20 bytes.
Signed-off-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Cc: Marek Lindner <lindner_marek@yahoo.de>
Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

receive_bat_packet is not called with rcu_read_lock so we must ensure by
ourself that we protect list_for_each_entry_rcu using the correct RCU
locks.
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

kmalloc() may fail, if so drop current packet.
Signed-off-by: NVasiliy Kulikov <segooon@gmail.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
[sven.eckelmann@gmx.de: Removed new introduced deadlock]
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Information about dropped packets are usually only interesting for
debugging purposes and otherwise open the possibility to flood the logs
of the target machine with useless information.

pr_debug will not output those information on a nodebug kernel.
Reported-by: NVasiliy Kulikov <segooon@gmail.com>
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

batman_if has the name of the net_dev as extra string in its own
structure, but also holds a reference to the actual net_device structure
which always has the current name of the device. This makes it
unneccessary and also more complex because we must update the name in
situations when we receive a NETDEV_CHANGENAME event.
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch removes all remaining global variables and includes the
necessary bits into the bat_priv structure. It is the last
remaining piece to allow multiple concurrent mesh clouds on the
same device.
A few global variables have been rendered obsolete during the process
and have been removed entirely.
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
[sven.eckelmann@gmx.de: Rework on top of current version]
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch replaces the static bat0 interface with a dynamic/abstracted
approach. It is now possible to create multiple batX interfaces by
assigning hard interfaces to them. Each batX interface acts as an
independent mesh network. A soft interface is removed once no hard
interface references it any longer.
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
[sven.eckelmann@gmx.de: Rework on top of current version]
Signed-off-by: NSven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>