Commit Graph

263 Commits

Author SHA1 Message Date
Antonio Quartulli 8b8e4bc039 batman-adv: fix race condition in TT full-table replacement
bug introduced with cea194d90b11aff7fc289149e4c7f305fad3535a

In the current TT code, when a TT_Response containing a full table is received
from an originator, first the node purges all the clients for that originator in
the global translation-table and then merges the newly received table.
During the purging phase each client deletion is done by means of a call_rcu()
invocation and at the end of this phase the global entry counter for that
originator is set to 0. However the invoked rcu function decreases the global
entry counter for that originator by one too and since the rcu invocation is
likely to be postponed, the node will end up in first setting the counter to 0
and then decreasing it one by one for each deleted client.

This bug leads to having a wrong global entry counter for the related node, say
X. Then when the node with the broken counter will answer to a TT_REQUEST on
behalf of node X, it will create faulty TT_RESPONSE that will generate an
unrecoverable situation on the node that asked for the full table recover.

The non-recoverability is given by the fact that the node with the broken
counter will keep answering on behalf of X because its knowledge about X's state
(ttvn + tt_crc) is correct.

To solve this problem the counter is not explicitly set to 0 anymore and the
counter decrement is performed right before the invocation of call_rcu().

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-06-23 17:21:35 +02:00
Marek Lindner 5870adc68f batman-adv: only drop packets of known wifi clients
bug introduced with 59b699cdee

If the source or destination mac address of an ethernet packet
could not be found in the translation table the packet was
dropped if AP isolation was turned on. This behavior would
make it impossible to send broadcast packets over the mesh as
the broadcast address will never enter the translation table.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Acked-by: Antonio Quartulli <ordex@autistici.org>
2012-06-23 17:21:11 +02:00
Antonio Quartulli 2c995ff892 batman-adv: fix skb->data assignment
skb_linearize(skb) possibly rearranges the skb internal data and then changes
the skb->data pointer value. For this reason any other pointer in the code that
was assigned skb->data before invoking skb_linearise(skb) must be re-assigned.

In the current tt_query message handling code this is not done and therefore, in
case of skb linearization, the pointer used to handle the packet header ends up
in pointing to free'd memory.

This bug was introduced by a73105b8d4
(batman-adv: improved client announcement mechanism)

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-19 14:49:08 -07:00
Antonio Quartulli 521251f2f5 batman-adv: unset the TT_CLIENT_PENDING flag if the new local entry already exists
When trying to add a new tt_local_entry, if such entry already exists, we have
to ensure that the TT_CLIENT_PENDING flag is not set, otherwise the entry will
be deleted soon.

Reported-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-14 09:05:08 +02:00
Sven Eckelmann e01572654a batman-adv: Start new development cycle
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-13 19:06:42 +02:00
Sven Eckelmann 679695813c batman-adv: use shorter pr_warn instead of pr_warning
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-13 19:06:41 +02:00
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
Marek Lindner e3b0d0dea6 batman-adv: prepare lq_update_lock to be shared among different protocols
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-13 19:06:39 +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
Antonio Quartulli 35c133a000 batman-adv: add contributor name
translation_table.{c,h} have been heavily modified by another contributor and
for legal purposes it is better to include his name into the contributor list

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:56:08 +02:00
Antonio Quartulli c64703aace batman-adv: update copyright years
update copyright years in order to include 2012

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:56:07 +02:00
Marek Lindner fefa532971 batman-adv: fix checkpatch string complaint
Regression introduced by: f76d019194e0a88c57371df169ecc979690a04c2

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:56:06 +02:00
Marek Lindner 13b2541b11 batman-adv: avoid temporary routing loops by being strict on forwarded OGMs
batman-adv would forward OGMs from non-besthops while replacing the the TQ
and TTL values with the values from the best hop. In certain corner cases
this leads to a temporary routing loop.
This patch changes this behavior: Only packets from best next hops are
forwarded - TQ and TTL values won't be replaced anymore. However, the protocol
needs to rebroadcast OGMs from single hop neighbors regardless of whether or
not they are the best hop. To handle this case a new flag is introduced to
alert neighboring nodes about the forwarded OGM that is not from my best
next hop. It is to be discarded by all nodes except for the one originating
the OGM.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Acked-by: Daniele Furlan <daniele.furlan@gmail.com>
Tested-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
2012-05-11 13:56:05 +02:00
Linus Luessing 9d853f6246 batman-adv: Adding hard_iface specific sysfs wrapper macros for UINT
This allows us to easily add a sysfs parameter for an unsigned int
later, which is not for a batman mesh interface (e.g. bat0), but for a
common interface instead. It allows reading and writing an atomic_t in
hard_iface (instead of bat_priv compared to the mesh variant).

Developed by Linus during a 6 months trainee study period in Ascom
(Switzerland) AG.

Signed-off-by: Linus Luessing <linus.luessing@web.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2012-05-11 13:56:03 +02:00
Marek Lindner f245c38ba7 batman-adv: rename sysfs macros to reflect the soft-interface dependency
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:56:02 +02:00
Marek Lindner c32293983d batman-adv: refactoring API: find generalized name for bat_ogm_update_mac callback
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:56:01 +02:00
Marek Lindner edbf12ba56 batman-adv: ignore protocol packets if the interface did not enable this protocol
Reported-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:55:59 +02:00
Marek Lindner 7ae8b2852f batman-adv: split neigh_new function into generic and batman iv specific parts
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 13:55:57 +02:00
Marek Lindner 0b0094e000 batman-adv: replace HZ calculations with jiffies_to_msecs()
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 10:08:13 +02:00
Marek Lindner d7b2a97e03 batman-adv: rename last_valid to last_seen
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 10:08:12 +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
Marek Lindner ffa995e036 batman-adv: introduce packet type handler array for incoming packets
The packet handler array replaces the growing switch statement, thus
dealing with incoming packets in a more efficient way. It also adds
to possibility to register packet handlers on the fly.

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 10:08:10 +02:00
Marek Lindner 75cd33f863 batman-adv: introduce is_single_hop_neigh variable to increase readability
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 10:08:09 +02:00
Antonio Quartulli 9205cc521e batman-adv: fix wrong dhcp option list browsing
In is_type_dhcprequest(), while parsing a DHCP message, if the entry we found in
the option list is neither a padding nor the dhcp-type, we have to ignore it and
jump as many bytes as its length + 1. The "+ 1" byte is given by the subtype
field itself that has to be jumped too.

Reported-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 10:08:08 +02:00
Antonio Quartulli 1e5cc266db batman-adv: skip the window protection test when the originator has no neighbours
When we receive an OGM from from a node for the first time, the last_real_seqno
field of the orig_node structure has not been initialised yet. The value of this
field is used to compute the current ogm-seqno window and therefore the
protection mechanism will probably drop the packet due to an out-of-window error.
To avoid this situation this patch adds a check to skip the window protection
mechanism if no neighbour nodes have already been added. When the first
neighbour node is added, the last_real_seqno field is initialised too.

Reported-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:54:02 +02:00
Antonio Quartulli c97c72b493 batman-adv: print OGM seq numbers as unsigned int
OGM sequence numbers are declared as uint32_t and so they have to printed
using %u instead of %d in order to avoid wrong representations.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:54:02 +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 1eeb479fda batman-adv: mark existing ogm variables as batman iv
The coming protocol changes also will have a part called "OGM". That
makes it necessary to introduce a distinction in the code base.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
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
Marek Lindner cd8b78e7e9 batman-adv: refactoring API: find generalized name for bat_ogm_init_primary callback
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
Marek Lindner 77af7575c4 batman-adv: handle routing code initialization properly
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:53:59 +02:00
Marek Lindner 00a50076a3 batman-adv: add iface_disable() callback to routing API
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:53:59 +02:00
Marek Lindner d7d32ec0f1 batman-adv: randomize initial seqno to avoid collision
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:53:58 +02:00
Marek Lindner c2aca02235 batman-adv: refactoring API: find generalized name for bat_ogm_init callback
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:53:58 +02:00
Marek Lindner 8140625e30 batman-adv: move ogm initialization into the proper function
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:53:57 +02:00
Antonio Quartulli e88af9464f batman-adv: remove duplicated line in comment
Remove an accidentally added duplicated line in a function comment

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:53:57 +02:00
Antonio Quartulli 6d2003fc26 batman-adv: convert the tt_crc to network order
Before sending out a TT_Request packet we must convert the tt_crc field value
to network order (since it is 16bits long).

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-18 09:43:36 +02:00
Eric Dumazet 95c9617472 net: cleanup unsigned to unsigned int
Use of "unsigned int" is preferred to bare "unsigned" in net tree.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15 12:44:40 -04:00
Simon Wunderlich 7a5cc24277 batman-adv: add bridge loop avoidance compile option
The define CONFIG_BATMAN_ADV_BLA switches the bridge loop avoidance
on - skip it, and the bridge loop avoidance is not compiled in.

This is useful if binary size should be saved or the feature is
not needed.

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-11 14:29:00 +02:00
Simon Wunderlich 38ef3d1d91 batman-adv: form groups in the bridge loop avoidance
backbone gateways may be part of the same LAN, but participate
in different meshes. With this patch, backbone gateways form groups by
applying the groupid of another backbone gateway if it is higher. After
forming the group, they only accept messages from backbone gateways of
the same group.

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 b1a8c04b8a batman-adv: drop STP over batman
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 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 db08e6e557 batman-adv: allow multiple entries in tt_global_entries
as backbone gateways will all independently announce the same clients,
also the tt global table must be able to hold multiple originators per
client entry.

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 9bf8e4d425 batman-adv: export claim tables through debugfs
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 c867305509 batman-adv: make bridge loop avoidance switchable
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
Marek Lindner 8681a1c4dd batman-adv: encourage batman to take shorter routes by changing the default hop penalty
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-04-11 14:28:58 +02:00