Commit Graph

46 Commits

Author SHA1 Message Date
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
Linus Lüssing 7cefb149a6 batman-adv: Remove unused hdr_size variable in route_unicast_packet()
Signed-off-by: Linus Lüssing <linus.luessing@ascom.ch>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:52:08 +01:00
Marek Lindner e6c10f433a batman-adv: rename batman_if struct to hard_iface
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:52:06 +01:00
Marek Lindner 4389e47af8 batman-adv: rename global if_list to hardif_list
Batman-adv works with "hard interfaces" as well as "soft interfaces".
The new name should better make clear which kind of interfaces this
list stores.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:52:05 +01:00
Marek Lindner d0072609ba batman-adv: remove orig_hash spinlock
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:52:04 +01:00
Marek Lindner 1605d0d60b batman-adv: increase refcount in create_neighbor to be consistent
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:52:03 +01:00
Marek Lindner 7b36e8eef9 batman-adv: Correct rcu refcounting for orig_node
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: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:52:01 +01:00
Marek Lindner 7aadf889e8 batman-adv: remove extra layer between hash and hash element - hash bucket
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:52:00 +01:00
Marek Lindner 39901e7162 batman-adv: separate ethernet comparing calls from hash functions
Note: The function compare_ether_addr() provided by the Linux kernel
requires aligned memory.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:50:14 +01:00
Marek Lindner f3e0008f01 batman-adv: make broadcast seqno operations atomic
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: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:50:09 +01:00
Marek Lindner 0ede9f41b2 batman-adv: protect bit operations to count OGMs with spinlock
Reported-by: Linus Lüssing <linus.luessing@saxnet.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:50:08 +01:00
Marek Lindner 44524fcdf6 batman-adv: Correct rcu refcounting for neigh_node
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: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:50:03 +01:00
Simon Wunderlich a4c135c561 batman-adv: protect bonding with rcu locks
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: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:50:01 +01:00
Marek Lindner 2ae2daf6c3 batman-adv: protect ogm counter arrays with spinlock
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:50:00 +01:00
Marek Lindner 16b1aba849 batman-adv: protect originator nodes with reference counters
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:49:59 +01:00
Marek Lindner fb778ea173 batman-adv: protect each hash row with rcu locks
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:49:58 +01:00
Marek Lindner a775eb847a batman-adv: protect neigh_nodes used outside of rcu_locks with refcounting
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:49:57 +01:00
Marek Lindner f987ed6ebd batman-adv: protect neighbor list with rcu locks
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:49:54 +01:00
Marek Lindner 9591a79f28 batman-adv: convert neighbor list to hlist
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:49:53 +01:00
Marek Lindner a8e7f4bc38 batman-adv: protect neighbor nodes with reference counters
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:49:52 +01:00
Linus Lüssing ee1e884194 batman-adv: Remove duplicate types.h inclusions
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: Linus Lüssing <linus.luessing@ascom.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-02-11 23:30:29 +01:00
Sven Eckelmann 64afe35398 batman-adv: Update copyright years
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-01-31 14:57:12 +01:00
Sven Eckelmann 1299bdaa1c batman-adv: Remove unused variables
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-01-31 14:57:12 +01:00
Simon Wunderlich 74ef115359 batman-adv: remove unused parameters
Some function parameters are obsolete now and can be removed.

Reported-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-01-31 14:57:09 +01:00
Sven Eckelmann ae361ce19f batman-adv: Calculate correct size for merged packets
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: Russell Senior <russell@personaltelco.net>
Reported-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-01-31 14:57:08 +01:00
Sven Eckelmann c6c8fea297 net: Add batman-adv meshing protocol
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: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-16 13:44:24 -08:00