Commit Graph

75 Commits

Author SHA1 Message Date
Marek Lindner 8c7bf248a3 batman-adv: refactor window_protected to avoid unnecessary return statement
Reported-by: David Laight <David.Laight@aculab.com>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-13 19:06:40 +02:00
Antonio Quartulli 3275e7cc84 batman-adv: improve unicast packet (re)routing
In case of a client X roaming from a generic node A to another node B, it is
possible that a third node C gets A's OGM but not B's. At this point in time, if
C wants to send data to X it will send a unicast packet destined to A. The
packet header will contain A's last ttvn (C got A's OGM and so it knows it).

The packet will travel towards A without being intercepted because the ttvn
contained in its header is the newest for A.

Once A will receive the packet, A's state will not report to be in a "roaming
phase" (because, after a roaming, once A sends out its OGM, all the changes are
committed and the node is considered not to be in the roaming state anymore)
and it will match the ttvn carried by the packet. Therefore there is no reason
for A to try to alter the packet's route, thus dropping the packet because the
destination client is not there anymore.

However, C is well aware that it's routing information towards the client X is
outdated as it received an OGM from A saying that the client roamed away.
Thanks to this detail, this patch introduces a small change in behaviour: as
long as C is in the state of not knowing the new location of client X it will
forward the traffic to its last known location using ttvn-1 of the destination.
By using an older ttvn node A will be forced to re-route the packet.
Intermediate nodes are also allowed to update the packet's destination as long
as they have the information about the client's new location.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-13 19:06:38 +02:00
Antonio Quartulli 8710e2613a batman-adv: avoid skb_linearise() if not needed
Whenever we want to access headers only, we do not need to linearise the whole
packet. Instead we can use pskb_may_pull()

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-13 18:24:37 +02:00
Marek Lindner c3e29312c8 batman-adv: register batman ogm receive function during protocol init
The B.A.T.M.A.N. IV OGM receive function still was hard-coded although
it is a routing protocol specific function. This patch takes advantage
of the dynamic packet handler registration to remove the hard-coded
function calls.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Acked-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 10:08:11 +02:00
Antonio Quartulli 0d125074eb batman-adv: use ETH_HLEN instead of sizeof(struct ethhdr)
Instead of using sizeof(struct ethhdr) it is strongly recommended to use the
kernel macro ETH_HLEN. This patch substitute each occurrence of the former
expressione with the latter one.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:54:01 +02:00
Marek Lindner 76e3d7fc1a batman-adv: rename BATMAN_OGM_LEN to BATMAN_OGM_HLEN
Using BATMAN_OGM_LEN leaves one with the impression that this is
the full packet size which is not the case. Therefore the variable
is renamed.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:54:00 +02:00
Simon Wunderlich fe2da6ff27 batman-adv: add broadcast duplicate check
When multiple backbone gateways relay the same broadcast from the
backbone into the mesh, other nodes in the mesh may receive this
broadcast multiple times. To avoid this, the crc checksums of
received broadcasts are recorded and new broadcast packets with
the same content may be dropped if received by another gateway.

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-11 14:28:59 +02:00
Simon Wunderlich 20ff9d593f batman-adv: don't let backbone gateways exchange tt entries
As the backbone gateways are connected to the same backbone, they
should announce the same clients on the backbone non-exclusively.

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-11 14:28:59 +02:00
Simon Wunderlich 23721387c4 batman-adv: add basic bridge loop avoidance code
This second version of the bridge loop avoidance for batman-adv
avoids loops between the mesh and a backbone (usually a LAN).

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.

With this patch, batman recognizes backbone gateways, nodes which are
part of the mesh and backbone/LAN at the same time. Each backbone
gateway "claims" clients from within the mesh to handle them
exclusively. By restricting that only responsible backbone gateways
may handle their claimed clients traffic, loops are effectively
avoided.

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-11 14:28:58 +02:00
Simon Wunderlich a7f6ee9493 batman-adv: remove old bridge loop avoidance code
The functionality is to be replaced by an improved implementation,
so first clean up.

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-11 14:28:58 +02:00
Sven Eckelmann 0079d2cef1 batman-adv: Replace bitarray operations with bitmap
bitarray.c consists mostly of functionality that is already available as part
of the standard kernel API. batman-adv could use architecture optimized code
and reduce the binary size by switching to the standard functions.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-11 14:28:58 +02:00
Sven Eckelmann 96741ade15 batman-adv: Use {} braces consistent on the arms of a statement
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2012-03-11 06:29:44 +08:00
Sven Eckelmann 86ceb36056 batman-adv: Ignore 80-chars per line limits for strings
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2012-03-11 06:29:44 +08:00
Sven Eckelmann 7c64fd98ce batman-adv: Fix indentation of multiline statements
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2012-02-28 19:14:31 +08:00
Sven Eckelmann 567db7b0b7 batman-adv: Update copyright years
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2012-02-17 02:50:21 +08:00
Marek Lindner 032b7969f8 batman-adv: convert time_after instances to has_timed_out
To increase readability the has_timed_out() functions has been introduced.
This patch converts existing time_after() calls to use this wrapper
function (if applicable).
This patch also converts all timeouts to miliseconds to be consistent.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
2012-02-17 02:50:20 +08:00
Marek Lindner 01c4224b51 batman-adv: convert batman iv algorithm to use dynamic infrastructure
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2012-02-17 02:50:20 +08:00
Marek Lindner 8780dad9e9 batman-adv: simplify bat_ogm_receive API call
Most of the values in that call are derived from the skb, so we can hand
over the skb instead.

Reported-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2012-02-17 02:50:19 +08:00
Sven Eckelmann 76543d14ae batman-adv: Explicitly mark the common header structure
All batman-adv packets have a common 3 byte header. It can be used to share
some code between different code paths, but it was never explicit stated that
this header has to be always the same for all packets. Therefore, new code
changes always have the problem that they may accidently introduce regressions
by moving some elements around.

A new structure is introduced that contains the common header and makes it
easier visible that these 3 bytes have to be the same for all on-wire packets.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2012-02-17 02:50:19 +08:00
Antonio Quartulli 69497c17c6 batman-adv: format multi-line if in the correct way
in an multi-line if statement leading edges should line up to the opening
parenthesis

Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-12-07 02:45:59 +08:00
Antonio Quartulli 8b7342d673 batman-adv: check for tt_reponse packet real length
Before accessing the TT_RESPONSE packet payload, the node has to ensure that the
packet is long enough as it would expect to be.

Reported-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-11-20 13:08:34 +01:00
Antonio Quartulli dc58fe32e6 batman-adv: linearise the tt_response skb only if needed
The TT_RESPONSE skb has to be linearised only if the node plans to access the
packet payload (so only if the message is directed to that node). In all the
other cases the node can avoid this memory operation

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-11-20 13:08:34 +01:00
Antonio Quartulli c90681b850 batman-adv: fixed hash functions type to uint32_t instead of int
There are two reasons for this fix:
- the result of choose_orig() and vis_choose() is an index and therefore it can't
  be negative. Hence it is correct to make the return type unsigned too.

- sizeof(int) may not be the same on ALL the architectures. Since we plan to use
  choose_orig() as DHT hash function, we need to guarantee that, given the same
  argument, the result is the same. Then it is correct to explicitly express
  the size of the return type (and the second argument). Since the expected
  length is currently 4, uint32_t is the most convenient choice.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-11-20 13:08:33 +01:00
Marek Lindner fc95727564 batman-adv: agglomerate all batman iv ogm processing functions in a single file
In preparation of the upcoming improved routing algorithm the code based has
to be re-organized to allow choosing the routing algorithm at compile time.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-09-08 17:39:06 +02:00
Marek Lindner b6da4bf5d7 batman-adv: rename all instances of batman_packet to batman_ogm_packet
The follow-up routing code changes are going to introduce additional
routing packet types which make this distinction necessary.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-09-08 17:37:51 +02:00
Marek Lindner a943cac144 batman-adv: merge update_transtable() into tt related code
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-08-22 15:16:22 +02:00
Antonio Quartulli 3d393e4732 batman-adv: implement AP-isolation on the sender side
If a node has to send a packet issued by a WIFI client to another WIFI client,
the packet is dropped.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-08-22 15:16:21 +02:00
Antonio Quartulli bc2790808a batman-adv: detect clients connected through a 802.11 device
Clients connected through a 802.11 device are now marked with the
TT_CLIENT_WIFI flag. This flag is also advertised with the tt
announcement.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-08-22 15:16:20 +02:00
Antonio Quartulli 015758d002 batman-adv: correct several typ0s in the comments
Several typos have been corrected and some sentences have been rephrased

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-08-22 15:16:19 +02:00
Antonio Quartulli a7f9becb7d batman-adv: request the full table if tt_crc doesn't match
In case of tt_crc mismatching for a certain orig_node after applying the
changes, the node must request the full table immediately.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-07-07 18:49:26 +02:00
Antonio Quartulli 8698529d20 batman-adv: add_bcast_packet_to_list() takes the sending delay as parameter
In order to make possible to use the broadcast list for delayed sendings
the "delay" parameter is now provided instead of using 1 as hardcoded
value.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-07-05 14:28:54 +02:00
Antonio Quartulli 7683fdc1e8 batman-adv: protect the local and the global trans-tables with rcu
The local and the global translation-tables are now lock free and rcu
protected.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Acked-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-06-20 11:37:30 +02:00
Antonio Quartulli cc47f66e6b batman-adv: improved roaming mechanism
With the current client announcement implementation, in case of roaming,
an update is triggered on the new AP serving the client. At that point
the new information is spread around by means of the OGM broadcasting
mechanism. Until this operations is not executed, no node is able to
correctly route traffic towards the client. This obviously causes packet
drops and introduces a delay in the time needed by the client to recover
its connections.

A new packet type called ROAMING_ADVERTISEMENT is added to account this
issue.

This message is sent in case of roaming from the new AP serving the
client to the old one and will contain the client MAC address. In this
way an out-of-OGM update is immediately committed, so that the old node
can update its global translation table. Traffic reaching this node will
then be redirected to the correct destination utilising the fresher
information. Thus reducing the packet drops and the connection recovery
delay.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-06-20 11:37:27 +02:00
Antonio Quartulli a73105b8d4 batman-adv: improved client announcement mechanism
The client announcement mechanism informs every mesh node in the network
of any connected non-mesh client, in order to find the path towards that
client from any given point in the mesh.

The old implementation was based on the simple idea of appending a data
buffer to each OGM containing all the client MAC addresses the node is
serving. All other nodes can populate their global translation tables
(table which links client MAC addresses to node addresses) using this
MAC address buffer and linking it to the node's address contained in the
OGM. A node that wants to contact a client has to lookup the node the
client is connected to and its address in the global translation table.

It is easy to understand that this implementation suffers from several
issues:
 - big overhead (each and every OGM contains the entire list of
   connected clients)
 - high latencies for client route updates due to long OGM trip time and
   OGM losses

The new implementation addresses these issues by appending client
changes (new client joined or a client left) to the OGM instead of
filling it with all the client addresses each time. In this way nodes
can modify their global tables by means of "updates", thus reducing the
overhead within the OGMs.

To keep the entire network in sync each node maintains a translation
table version number (ttvn) and a translation table checksum. These
values are spread with the OGM to allow all the network participants to
determine whether or not they need to update their translation table
information.

When a translation table lookup is performed in order to send a packet
to a client attached to another node, the destination's ttvn is added to
the payload packet. Forwarding nodes can compare the packet's ttvn with
their destination's ttvn (this node could have a fresher information
than the source) and re-route the packet if necessary. This greatly
reduces the packet loss of clients roaming from one AP to the next.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-06-20 11:37:24 +02:00
Sven Eckelmann b4e1705417 batman-adv: Reduce usage of char
char was used in different places to store information without really
using the characteristics of that data type or by ignoring the fact that
char has not a well defined signedness.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-06-20 11:37:18 +02:00
David Howells b2c44a5383 batman-adv: count_real_packets() in batman-adv assumes char is signed
count_real_packets() in batman-adv assumes char is signed, and returns -1
through it:

net/batman-adv/routing.c: In function 'receive_bat_packet':
net/batman-adv/routing.c:739: warning: comparison is always false due to limited range of data type

Use int instead.

Signed-off-by: David Howells <dhowells@redhat.com>
[sven@narfation.org: Rebase on top of current version]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-06-20 11:23:36 +02:00
Daniele Furlan d1829fa0c3 batman-adv: accept delayed rebroadcasts to avoid bogus routing under heavy load
When a link is saturated (re)broadcasts of OGMs are delayed. Under heavy
load this delay may exceed the orig interval which leads to OGMs being
dropped (the code would only accept an OGM rebroadcast if it arrived
before the next OGM was broadcasted). With this patch batman-adv will
also accept delayed OGMs in order to avoid a bogus influence on the
routing metric.

Signed-off-by: Daniele Furlan <daniele.furlan@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-06-09 20:40:37 +02:00
Sven Eckelmann bb899b89f4 batman-adv: Ensure that we really have route changes in update_route
The debug output of update_route has tests for "route deleted" and "route
added". All other situations are handled as "route changed". This is not
true because neigh_node and curr_router could be both NULL.

The function is not called in this situation, but the code might be
interpreted wrong when reading it without this test.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-30 07:39:37 +02:00
Antonio Quartulli 44e92bc8d6 batman-adv: use is_broadcast_ether_addr() instead of compare_eth(.., brd_addr)
Instead of comparing mac addresses with the broadcast address by means
of compare_eth(), the is_broadcast_ether_addr() kernel function has to be
used.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-30 07:39:36 +02:00
Sven Eckelmann 704509b8d4 batman-adv: Calculate sizeof using variable insead of types
Documentation/CodingStyle recommends to use the form

	p = kmalloc(sizeof(*p), ...);

to calculate the size of a struct and not the version where the struct
name is spelled out to prevent bugs when the type of p changes. This
also seems appropriate for manipulation of buffers when they are
directly associated with p.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-30 07:39:33 +02:00
Sven Eckelmann 747e4221a0 batman-adv: Add const type qualifier for pointers
batman-adv uses pointers which are marked as const and should not
violate that type qualifier by passing it to functions which force a
cast to the non-const version.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-30 07:39:31 +02:00
Antonio Quartulli e2cbc11c0e batman-adv: move neigh_node->if_incoming->if_status check in find_router()
Every time that find_router() is invoked, if_status has to be compared with
IF_ACTIVE. Moving this comparison inside find_router() will avoid to write it
each time.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-30 07:39:27 +02:00
Daniele Furlan 27aea2128e batman-adv: remove duplicate code from function is_bidirectional_neigh()
In function is_bidirectional_neigh the code that find out the one hop
neighbor is duplicated.

Signed-off-by: Daniele Furlan <daniele.furlan@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-08 16:10:42 +02:00
Antonio Quartulli 2dafb49d84 batman-adv: rename everything from *hna* into *tt* (translation table)
To be coherent, all the functions/variables/constants have been renamed
to the TranslationTable style

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-08 16:10:42 +02:00
Marek Lindner 01df2b65e9 batman-adv: Fix refcount imbalance in find_router
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-08 16:10:42 +02:00
Marek Lindner 32ae9b221e batman-adv: Make bat_priv->primary_if an rcu protected pointer
The rcu protected macros rcu_dereference() and rcu_assign_pointer()
for the bat_priv->primary_if need to be used, as well as spin/rcu locking.

Otherwise we might end up using a primary_if pointer pointing to already
freed memory.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-01 22:49:03 +02:00
Antonio Quartulli b5a6f69c5c batman-adv: orig_hash_find() manages rcu_lock/unlock internally
orig_hash_find() manages rcu_lock/unlock internally and doesn't need to
be surrounded by rcu_read_lock() / rcu_read_unlock() anymore

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Acked-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-01 22:49:02 +02:00
Linus Lüssing 68003903e4 batman-adv: Protect global TQ window with a spinlock
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-04-17 21:11:01 +02:00
Linus Lüssing e1a5382f97 batman-adv: Make orig_node->router an rcu protected pointer
The rcu protected macros rcu_dereference() and rcu_assign_pointer()
for the orig_node->router need to be used, as well as spin/rcu locking.
Otherwise we might end up using a router pointer pointing to already
freed memory.

Therefore this commit introduces the safe getter method
orig_node_get_router().

Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-04-17 21:11:01 +02:00
Linus Lüssing 551586292b batman-adv: Move bonding / iface alternating router search to own functions
This decreases the size of find_router() by outsourcing the router
search for the bonding and interface alternating modes to their own sub
functions. This shall make it easier to keep track of the correct
refcounting later.

Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-04-17 21:11:00 +02:00