To keep transtable consistency among all the nodes, an originator must
not send not yet announced clients within a full table TT_RESPONSE.
Instead, deleted client have to be kept in the table in order to be sent
within an immediate TT_RESPONSE. In this way all the nodes in the
network will always provide the same response for the same request.

All the modification are committed at the next ttvn increment event.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>

The last_ttvn and tt_crc fields of the orig_node structure were not
initialised causing an immediate TT_REQ/RES dialogue even if not needed.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>

The version number of modules build outside of the tree can get revision
numbers added. This is useful to give hints about the revision of a
distribution package and the used patchset. The prepended source number or
branch name doesn't add any additional information which would help to identify
problems and can therefore be omitted.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>

The packet aggregation needs to ensure that only compatible packets
are aggregated. Some of the checks are based on the interface number
while assuming that the first interface also is the primary interface
which is not always the case.
This patch addresses the issue by using the primary_if pointer.
Reported-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>

The primary interface OGM has to be broadcasted on all hard-interfaces
even if the primary interface is not the first interface (if_num = 0).
Therefore the code has to compare the originating interface with the
primary interface instead of checking the if_num.
Reported-by: Linus Luessing <linus.luessing@web.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>

now tt_local_event() takes a flags argument instead of a sequence of
boolean values which would grow up with the time.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>

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>

The tt_local_entry structure now has a 'flags' field. This helps to
unify the flags format to all the client related structures (tt_global_entry
and tt_change). The 'never_purge' field is now encoded in the 'flags' one.
To optimise the usage of this field, its length has been increased to 16bit
in order to use the eight leading bits (from 0 to 7) to store flags that
have to be sent on the wire, while the eight ending ones are used for local
computation only.

Moreover 'enum tt_change_flags' is now called 'enum tt_client_flags' and the
defined values apply to the tt_local_entry, tt_global_entry and the tt_change
'flags' field.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>

If a client issues a DHCPREQUEST for renewal, the packet is dropped
if the old destination (the old gateway for the client) TQ is smaller
than the current best gateway TQ less GW_THRESHOLD
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>

In case of new default gw, changing the default gw or deleting the default gw a
uevent is triggered with type=gw, action=add/change/del and
data={GW_ORIG_ADDRESS} (if any).
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>

The gateway election mechanism has been a little revised. Now the
gw_election is trigered by an atomic_t flag (gw_reselect) which is set
to 1 in case of election needed, avoding to set curr_gw to NULL.
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>

Using throw_uevent() is now possible to trigger uevent signal that can
be recognised in userspace. Uevents will be triggered through the
/devices/virtual/net/{MESH_IFACE} kobject.

A triggered uevent has three properties:
- type: the event class. Who generates the event (only 'gw' is currently
  defined). Corresponds to the BATTYPE uevent variable.
- action: the associated action with the event ('add'/'change'/'del' are
  currently defined). Corresponds to the BATACTION uevent variable.
- data: any useful data for the userspace. Corresponds to the BATDATA
  uevent variable.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>

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>

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>

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>

The amount of duplicated code in the receive and routing code can be
reduced when all headers provide the packet type, version and ttl in the
same first bytes.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>

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>

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>

interface_tx is not used outside of soft-interface.c and thus doesn't
need to be declared inside soft-interface.h
Signed-off-by: Sven Eckelmann <sven@narfation.org>

compare_orig is only used in context of orig_node which is managed
inside originator.c. It is not necessary to keep that function inside
the header originator.h.
Signed-off-by: Sven Eckelmann <sven@narfation.org>

The definition NO_FLAGS was introduced to make the code more
readable and shall be used to initialize flag fields.
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>

CodingStyle "Chapter 12: Macros, Enums and RTL" recommends to use enums
for several related constants. Internal states can be used without
defining the actual value, but all values which are visible to the
outside must be defined as before. Normal values are assigned as usual
and flags are defined by shifts of a bit.
Signed-off-by: Sven Eckelmann <sven@narfation.org>

CodingStyle "Chapter 12: Macros, Enums and RTL" highly recommends to use
functions instead of macros were possible. This ensures type safety and
prevents shadowing of other variables.
Signed-off-by: Sven Eckelmann <sven@narfation.org>

strict_strtoul as used in parse_gw_bandwidth is defined for unsigned
long and strict_strtol should be used instead for long.
Signed-off-by: Sven Eckelmann <sven@narfation.org>

gw_node_delete is defined with "void" as return type, but still tries to
return a value. The called function gw_node_delete is also return as
void and thus doesn't provide a value for us.
Signed-off-by: Sven Eckelmann <sven@narfation.org>

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>

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>

This comment has been wrongly put after the variable it refers to and was also bad indented
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>

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>

seq_before and seq_after depend on the fact that both sequence numbers
have the same type and thus the same bitwidth. We can ensure that by
compile time checking using a compare between the pointer to the
temporary buffers which were created using the typeof of both
parameters. For example gcc would create a warning like
"warning: comparison of distinct pointer types lacks a cast".
Signed-off-by: Sven Eckelmann <sven@narfation.org>

smallest_signed_int(), seq_before() and seq_after() are very useful
functions that help to handle comparisons between sequence numbers.
However they were only defined in vis.c. With this patch every
batman-adv function will be able to use them.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>

Usually rcu_dereference isn't necessary in situations were the
RCU-protected data structure cannot change, but sparse and lockdep still
need a similar functionality for analysis. rcu_dereference_protected
implements the reduced version which should be used to support the
dynamic and static analysis.
Signed-off-by: Sven Eckelmann <sven@narfation.org>

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>

Casting from pointer like 'struct orig_node*' to 'struct orig_node *'
doesn't provide any additional functionality and can be savely removed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>

It is not necessary to cast a void* to the pointer type when we just
store it and don't want to do pointer arithmetic before the actual
assignment.
Signed-off-by: Sven Eckelmann <sven@narfation.org>

It is not save to provide memory for an int and then cast the pointer to
it to long*. It is better to standardize the up and down gateway
bandwith representation to simple ints and only use long inside
conversation routines.
Signed-off-by: Sven Eckelmann <sven@narfation.org>

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>

The size of void is currently set by gcc to 1, but is not well defined
in general. Therefore it is more advisable to cast it to char* before
doing pointer arithmetic.
Signed-off-by: Sven Eckelmann <sven@narfation.org>

Signed-off-by: Sven Eckelmann <sven@narfation.org>

Signed-off-by: Sven Eckelmann <sven@narfation.org>