With this patch, (re)broadcasting on a specific interfaces is avoided:

* No neighbor: There is no need to broadcast on an interface if there
  is no node behind it.

* Single neighbor is source: If there is just one neighbor on an
  interface and if this neighbor is the one we actually got this
  broadcast packet from, then we do not need to echo it back.

* Single neighbor is originator: If there is just one neighbor on
  an interface and if this neighbor is the originator of this
  broadcast packet, then we do not need to echo it back.

Goodies for BATMAN V:

("Upgrade your BATMAN IV network to V now to get these for free!")

Thanks to the split of OGMv1 into two packet types, OGMv2 and ELP
that is, we can now apply the same optimizations stated above to OGMv2
packets, too.

Furthermore, with BATMAN V, rebroadcasts can be reduced in certain
multi interface cases, too, where BATMAN IV cannot. This is thanks to
the removal of the "secondary interface originator" concept in BATMAN V.
Signed-off-by: NLinus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NSimon Wunderlich <sw@simonwunderlich.de>

Some variables are overwritten immediatelly in a functions. These don't
have to be initialized to a specific value on the stack because the value
will be overwritten before they will be used anywhere.
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NSimon Wunderlich <sw@simonwunderlich.de>

It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: NSimon Wunderlich <sw@simonwunderlich.de>

The routing API data structure contains several function
pointers that can easily be grouped together based on the
component they work with.

Split the API in subobjects in order to improve definition readability.

At the same time, remove the "bat_" prefix from the API object and
its fields names. These are batman-adv private structs and there is no
need to always prepend such prefix, which only makes function invocations
much much longer.
Signed-off-by: NAntonio Quartulli <a@unstable.cc>
Reviewed-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: NSimon Wunderlich <sw@simonwunderlich.de>

There are several places in batman-adv which provide logging related
functions. These should be grouped together in the log.* files to make them
easier to find.
Reported-by: NMarkus Pargmann <mpa@pengutronix.de>
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: NSimon Wunderlich <sw@simonwunderlich.de>

The bat_algo functionality in main.c is mostly unrelated to the rest of the
content. It still takes up a large portion of this source file (~15%, 103
lines). Moving it to a separate file makes it better visible as a main
component of the batman-adv implementation and hides it less in the other
helper functions in main.c.
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: NSimon Wunderlich <sw@simonwunderlich.de>

The tvlv functionality in main.c is mostly unrelated to the rest of the
content. It still takes up a large portion of this source file (~45%, 588
lines). Moving it to a separate file makes it better visible as a main
component of the batman-adv implementation and hides it less in the other
helper functions in main.c
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>
[sven@narfation.org: fix conflicts with current version, fix includes,
rewrote commit message]
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: NSimon Wunderlich <sw@simonwunderlich.de>

Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NSimon Wunderlich <sw@simonwunderlich.de>

The batadv_hardif_list list is checked in many situations and the items
in this list are given to specialized functions to modify the routing
behavior. At the moment each of these called functions has to check
itself whether the received batadv_hard_iface has a refcount > 0 before
it can increase the reference counter and use it in other objects.

This can easily lead to problems because it is not easily visible where
all callers of a function got the batadv_hard_iface object from and
whether they already hold a valid reference.

Checking the reference counter directly before calling a subfunction
with a pointer from the batadv_hardif_list avoids this problem.
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: NAntonio Quartulli <a@unstable.cc>

Since batadv_v_ogm_orig_update() was only called from one place and the
calling function became very short, merge these two functions together.

This should also reflect the protocol description of B.A.T.M.A.N. V
better.
Signed-off-by: NSimon Wunderlich <simon@open-mesh.com>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: NAntonio Quartulli <a@unstable.cc>

To match our code better to the protocol description of B.A.T.M.A.N. V,
move batadv_v_ogm_forward() out into batadv_v_ogm_process_per_outif()
and move all checks directly deciding whether the OGM should be
forwarded into batadv_v_ogm_forward().
Signed-off-by: NSimon Wunderlich <simon@open-mesh.com>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: NAntonio Quartulli <a@unstable.cc>

In case of wireless interface retrieve the throughput by
querying cfg80211. To perform this call a separate work
must be scheduled because the function may sleep and this
is not allowed within an RCU protected context (RCU in this
case is used to iterate over all the neighbours).

Use ethtool to retrieve information about an Ethernet link
like HALF/FULL_DUPLEX and advertised bandwidth (e.g.
100/10Mbps).

The metric is updated each time a new ELP packet is sent,
this way it is possible to timely react to a metric
variation which can imply (for example) a neighbour
disconnection.
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>

To enable ELP to send probing packets over wireless links
only if needed, batman-adv must keep track of the last time
it sent a unicast packet towards every neighbour.

For this purpose a 2 main changes are introduced:
1) a new member of the elp_neigh_node structure stores the
   last time a unicast packet was sent towards this neighbour;
2) a wrapper function for sending unicast packets is
   implemented. This function will simply update the member
   describe din point 1) and then forward the packet to the
   real sending routine.

Point 2) implies that any code-path leading to a unicast
sending now has to use the new wrapper.
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>

Add the support for recognising new originators in the
network and rebroadcast their OGMs.
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>

This is the initial implementation of the new OGM protocol
(version 2). It has been designed to work on top of the
newly added ELP.

In the previous version the OGM protocol was used to both
measure link qualities and flood the network with the metric
information. In this version the protocol is in charge of
the latter task only, leaving the former to ELP.

This means being able to decouple the interval used by the
neighbor discovery from the OGM broadcasting, which revealed
to be costly in dense networks and needed to be relaxed so
leading to a less responsive routing protocol.
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>