In case of an ARP message going in or out the soft_iface, it is intercepted and
a special action is performed. In particular the DHT helper functions previously
implemented are used to store all the ARP entries belonging to the network in
order to provide a fast and unicast lookup instead of the classic broadcast
flooding mechanism.
Each node stores the entries it is responsible for (following the DHT rules) in
its soft_iface ARP table. This makes it possible to reuse the kernel data
structures and functions for ARP management.
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

ARP messages are now parsed to make it possible to trigger special actions
depending on their types (snooping).
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Since batman-adv cannot inter-operate with the host ARP table, this patch
introduces a batman-adv private storage for ARP entries exchanged within DAT.
This storage will represent the node local cache in the DAT protocol.
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Add all the relevant functions in order to manage a Distributed Hash Table over
the B.A.T.M.A.N.-adv network. It will later be used to store several ARP entries
and implement DAT (Distributed ARP Table)
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

A new log level has been added to concentrate messages regarding DAT: ARP
snooping, requests, response and DHT related messages.
The new log level is named BATADV_DBG_DAT
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

The current unicast packet type does not contain the orig source address. This
patches add a new unicast packet (called UNICAST_4ADDR) which provides two new
fields: the originator source address and the subtype (the type of the data
contained in the packet payload). The former is useful to identify the node
which injected the packet into the network and the latter is useful to avoid
creating new unicast packet types in the future: a macro defining a new subtype
will be enough.
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Headers which are already perfectly aligned and create a 4 byte boundary
non-ethernet header payload can have the __packed attribute removed. The
__packed attribute doesn't change the appeareance of the packet for these
headers because no extra padding is necessary to align the data members. The
compiler will also create slightly faster code for loads of multi-byte members.
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

The ethernet header is 14 bytes long. Therefore, the data after it is not 4
byte aligned and may cause problems on systems without unaligned data access.
Reserving NET_IP_ALIGN more byes can fix the misalignment of the ethernet
header.
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

in case of client roaming a new global entry is added while a corresponding
local one is still present. In this case the node can safely pass the WIFI flag
from the local to the global entry.

This change is required to let the AP-isolation correctly working in case of
roaming: if a generic WIFI client C roams from node A to B, A adds a global
entry for C without adding any WIFI flag. The latter will be set only later,
once A has received C's advertisement from B. In this time period the
AP-Isolation (if enabled) would not correctly work since C is not marked as
WIFI, so allowing it to communicate with other WIFI clients.
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

In order to properly convert a bitwise AND to a boolean value, the whole
expression must be prepended by "!!".
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

In batadv_check_unicast_ttvn() the code accesses both the unicast header and the
Ethernet header in the payload. For this reason pskb_may_pull() must be invoked
to check for the required space.
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

To simplify TranslationTable debugging it is better to print the packet
rerouting message on the DBG_TT log level. In this way a developer interested in
packets rerouting doesn't need to filter it out of the whole ROUTES log.

Moreover, since this message will appear for each rerouted message, it is now
"ratelimited".
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

in case of a new global entry added because of roaming, the roam_at field must
be properly initiated with the current time. This value will be later use to
purge this entry out on time out (if nobody claims it). Instead roam_at field
is now set to zero in this situation leading to an immediate purging of the
related entry.
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

We have seen this to break networks when used with bridge loop
avoidance. As we can't see any benefit from sending these ancient frames
via our mesh, we just drop them.
Signed-off-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

The test whether we can use a router for alternating bonding should only be
done once because it is already known that it is still usable and will not be
deleted from the list soon.

This patch addresses Coverity #712285: Unchecked return value
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

New operations should not be started when they need an increased module
reference counter and try_module_get failed.

This patch addresses Coverity #712284: Unchecked return value
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

batadv_bit_get_packet checks for all common situations before it decides that
the new received packet indicates that the host was restarted. This extra
condition check at the end of the function is not necessary because this
condition is always true.

This patch addresses Coverity #712296: Logically dead code
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Transmissions over batman-adv devices always start another nested transmission
over devices attached to the batman-adv interface. These devices usually use
the ethernet lockdep class for the tx_queue lock which is also set by default
for all batman-adv devices. Lockdep will detect a nested locking attempt of two
locks with the same class and warn about a possible deadlock.

This is the default and expected behavior and should not alarm the locking
correctness prove mechanism. Therefore, the locks for all netdevice specific tx
queues get a special batman-adv lock class to avoid a false positive for each
transmission.
Reported-by: NLinus Luessing <linus.luessing@web.de>
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

In case of hash_add failure tt_global_add() must return 0 (which means on entry
insertion).
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

To avoid code duplication and to simplify further changes,
check_unicast_packet() is now used in recv_roam_adv() to check for not
well formed packets and so discard them.
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Threads in the bottom half of batadv_bla_check_bcast_duplist() might
otherwise for instance overwrite variables which other threads might
be using/reading at the same time in the top half, potentially
leading to messing up the bcast_duplist, possibly resulting in false
bridge loop avoidance duplicate check decisions.
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Acked-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

So far the crc16 checksum for a batman-adv broadcast data packet, received
on a batman-adv hard interface, was calculated over zero bytes of its
content leading to many incoming broadcast data packets wrongly being
dropped (60-80% packet loss).

This patch fixes this issue by calculating the crc16 over the actual,
complete broadcast payload.

The issue is a regression introduced by
("batman-adv: add broadcast duplicate check").
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Acked-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

If receiving an OGM from a neighbor other than the currently selected
and if it has the same TQ then we are supposed to switch if this
neighbor provides a more symmetric link than the currently selected one.

However this symmetry check currently is broken if the interface of the
neighbor we received the OGM from and the one of the currently selected
neighbor differ: We are currently trying to determine the symmetry of the
link towards the selected router via the link we received the OGM from
instead of just checking via the link towards the currently selected
router.

This leads to way more route switches than necessary and can lead to
permanent route flapping in many common multi interface setups.

This patch fixes this issue by using the right interface for this
symmetry check.
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>

Into function interface_set_mac_addr, the function tt_local_add was
invoked before updating dev->dev_addr. The new MAC address was not
tagged as NoPurge.
Signed-off-by: NDef <def@laposte.net>

On some architectures test_bit() can return other values than 0 or 1:

With a generic x86 OpenWrt image in a kvm setup (batadv_)test_bit()
frequently returns -1 for me, leading to batadv_iv_ogm_update_seqnos()
wrongly signaling a protected seqno window.

This patch tries to fix this issue by making batadv_test_bit() return 0
or 1 only.
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Acked-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

In order to understand  where a broadcast packet is coming from and use
this information to detect not yet announced clients, this patch modifies the
interface_rx() function by passing a new argument: the orig node
corresponding to the node that originated the received packet (if known).
This new argument if not NULL for broadcast packets only (other packets does not
have source field).
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

With the current TT mechanism a new client joining the network is not
immediately able to communicate with other hosts because its MAC address has not
been announced yet. This situation holds until the first OGM containing its
joining event will be spread over the mesh network.

This behaviour can be acceptable in networks where the originator interval is a
small value (e.g. 1sec) but if that value is set to an higher time (e.g. 5secs)
the client could suffer from several malfunctions like DHCP client timeouts,
etc.

This patch adds an early detection mechanism that makes nodes in the network
able to recognise "not yet announced clients" by means of the broadcast packets
they emitted on connection (e.g. ARP or DHCP request). The added client will
then be confirmed upon receiving the OGM claiming it or purged if such OGM
is not received within a fixed amount of time.
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

When enabling promiscuous mode, tt queries for other hosts might be
received. Before this patch, "foreign" tt queries were processed like
any other query and thus forwarded to its destination again and thereby
causing a loop.

This patch adds a check to drop foreign tt queries.
Signed-off-by: NMartin Hundebøll <martin@hundeboll.net>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

batadv_check_unicast_packet() is needed in batadv_recv_tt_query(), so
move the former to before the latter.
Signed-off-by: NMartin Hundebøll <martin@hundeboll.net>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

The structure batadv_priv grows everytime a new feature is introduced. It gets
hard to find the parts of the struct that belongs to a specific feature. This
becomes even harder by the fact that not every feature uses a prefix in the
member name.

The variables for bridge loop avoidence, gateway handling, translation table
and visualization server are moved into separate structs that are included in
the bat_priv main struct.
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

If this call fails, some of the orig_nodes spaces may have been
resized for the increased number of interface, and some may not.
If we would just continue with the larger number of interfaces,
this would lead to access to not allocated memory later.

We better check the return code, and don't add the interface if
no memory is available. OTOH, keeping some of the orig_nodes
with too much memory allocated should hurt no one (except for
a few too many bytes allocated).
Signed-off-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>

the word millisecond is misspelled in several comments. This patch fixes it.
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>