The code is broken and does not constrain sysctl_tcp_mem as
tcp_update_limit does.  With the result that it allows the cgroup tcp
memory limits to be bypassed.

The semantics are broken as the settings are not per netns and are in a
per netns table, and instead looks at current.

Since the code is broken in both design and implementation and does not
implement the functionality for which it was written remove it.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This function is never called. Remove it.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Changed key initialization of tcp_fastopen cookies to net_get_random_once.

If the user sets a custom key net_get_random_once must be called at
least once to ensure we don't overwrite the user provided key when the
first cookie is generated later on.

Cc: Yuchung Cheng <ycheng@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Initialize the ehash and ipv6_hash_secrets with net_get_random_once.

Each compilation unit gets its own secret now:
  ipv4/inet_hashtables.o
  ipv4/udp.o
  ipv6/inet6_hashtables.o
  ipv6/udp.o
  rds/connection.o

The functions still get inlined into the hashing functions. In the fast
path we have at most two (needed in ipv6) if (unlikely(...)).

Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch splits the secret key for syncookies for ipv4 and ipv6 and
initializes them with net_get_random_once. This change was the reason I
did this series. I think the initialization of the syncookie_secret is
way to early.

Cc: Florian Westphal <fw@strlen.de>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net_get_random_once is a new macro which handles the initialization
of secret keys. It is possible to call it in the fast path. Only the
initialization depends on the spinlock and is rather slow. Otherwise
it should get used just before the key is used to delay the entropy
extration as late as possible to get better randomness. It returns true
if the key got initialized.

The usage of static_keys for net_get_random_once is a bit uncommon so
it needs some further explanation why this actually works:

=== In the simple non-HAVE_JUMP_LABEL case we actually have ===
no constrains to use static_key_(true|false) on keys initialized with
STATIC_KEY_INIT_(FALSE|TRUE). So this path just expands in favor of
the likely case that the initialization is already done. The key is
initialized like this:

___done_key = { .enabled = ATOMIC_INIT(0) }

The check

                if (!static_key_true(&___done_key))                     \

expands into (pseudo code)

                if (!likely(___done_key > 0))

, so we take the fast path as soon as ___done_key is increased from the
helper function.

=== If HAVE_JUMP_LABELs are available this depends ===
on patching of jumps into the prepared NOPs, which is done in
jump_label_init at boot-up time (from start_kernel). It is forbidden
and dangerous to use net_get_random_once in functions which are called
before that!

At compilation time NOPs are generated at the call sites of
net_get_random_once. E.g. net/ipv6/inet6_hashtable.c:inet6_ehashfn (we
need to call net_get_random_once two times in inet6_ehashfn, so two NOPs):

      71:       0f 1f 44 00 00          nopl   0x0(%rax,%rax,1)
      76:       0f 1f 44 00 00          nopl   0x0(%rax,%rax,1)

Both will be patched to the actual jumps to the end of the function to
call __net_get_random_once at boot time as explained above.

arch_static_branch is optimized and inlined for false as return value and
actually also returns false in case the NOP is placed in the instruction
stream. So in the fast case we get a "return false". But because we
initialize ___done_key with (enabled != (entries & 1)) this call-site
will get patched up at boot thus returning true. The final check looks
like this:

                if (!static_key_true(&___done_key))                     \
                        ___ret = __net_get_random_once(buf,             \

expands to

                if (!!static_key_false(&___done_key))                     \
                        ___ret = __net_get_random_once(buf,             \

So we get true at boot time and as soon as static_key_slow_inc is called
on the key it will invert the logic and return false for the fast path.
static_key_slow_inc will change the branch because it got initialized
with .enabled == 0. After static_key_slow_inc is called on the key the
branch is replaced with a nop again.

=== Misc: ===
The helper defers the increment into a workqueue so we don't
have problems calling this code from atomic sections. A seperate boolean
(___done) guards the case where we enter net_get_random_once again before
the increment happend.

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch splits the inet6_ehashfn into separate ones in
ipv6/inet6_hashtables.o and ipv6/udp.o to ease the introduction of
seperate secrets keys later.

Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This duplicates a bit of code but let's us easily introduce
separate secret keys later. The separate compilation units are
ipv4/inet_hashtabbles.o, ipv4/udp.o and rds/connection.o.

Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now inet_gso_segment() is stackable, its relatively easy to
implement GSO/TSO support for IPIP

Performance results, when segmentation is done after tunnel
device (as no NIC is yet enabled for TSO IPIP support) :

Before patch :

lpq83:~# ./netperf -H 7.7.9.84 -Cc
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.9.84 () port 0 AF_INET
Recv   Send    Send                          Utilization       Service Demand
Socket Socket  Message  Elapsed              Send     Recv     Send    Recv
Size   Size    Size     Time     Throughput  local    remote   local   remote
bytes  bytes   bytes    secs.    10^6bits/s  % S      % S      us/KB   us/KB

 87380  16384  16384    10.00      3357.88   5.09     3.70     2.983   2.167

After patch :

lpq83:~# ./netperf -H 7.7.9.84 -Cc
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.9.84 () port 0 AF_INET
Recv   Send    Send                          Utilization       Service Demand
Socket Socket  Message  Elapsed              Send     Recv     Send    Recv
Size   Size    Size     Time     Throughput  local    remote   local   remote
bytes  bytes   bytes    secs.    10^6bits/s  % S      % S      us/KB   us/KB

 87380  16384  16384    10.00      7710.19   4.52     6.62     1.152   1.687
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In order to support GSO on IPIP, we need to make
inet_gso_segment() stackable.

It should not assume network header starts right after mac
header.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch makes gre_handle_offloads() more generic
and rename it to iptunnel_handle_offloads()

This will be used to add GSO/TSO support to IPIP tunnels.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While implementing GSO/TSO support for IPIP, I found skb_segment()
was assuming network header was immediately following mac header.

Its not really true in the case inet_gso_segment() is stacked :
By the time tcp_gso_segment() is called, network header points
to the inner IP header.

Let's instead assume nothing and pick the current offsets found in
original skb, we have skb_headers_offset_update() helper for that.

Also move the csum_start update inside skb_headers_offset_update()
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ipv6_gso_send_check() and ipv6_gso_segment() are called by
skb_mac_gso_segment() under rcu lock, no need to use
rcu_read_lock() / rcu_read_unlock()
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

inet_gso_segment() and inet_gso_send_check() are called by
skb_mac_gso_segment() under rcu lock, no need to use
rcu_read_lock() / rcu_read_unlock()

Avoid calling ip_hdr() twice per function.

We can use ip_send_check() helper.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The backbone gw check has to be VLAN specific so that code
using it can specify VID where the check has to be done.

In the TT code, the check has been moved into the
tt_global_add() function so that it can be performed on a
per-entry basis instead of ignoring all the TT data received
from another backbone node. Only TT global entries belonging
to the VLAN where the backbone node is connected to are
skipped.
All the other spots where the TT code was checking whether a
node is a backbone have been removed.

Moreover, batadv_bla_is_backbone_gw_orig() now returns bool
since it used to return only 1 or 0.

Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Instead of unconditionally removing all the TT entries
served by a given originator, make tt_global_orig_del()
remove only entries matching a given VLAN identifier
provided as argument.

If such argument is negative all the global entries
served by the originator are removed.

This change is used into the BLA code to purge entries
served by a newly discovered Backbone node, but limiting
the operation only to those connected to the VLAN where the
backbone has been discovered.

Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

This change allows nodes to handle the TT table on a
per-VLAN basis. This is needed because nodes may have to
store only some of the global entries advertised by another
node.

In this scenario such nodes would re-create only a partial
global table and would not be able to compute a correct CRC
anymore.

This patch splits the logic and introduces one CRC per VLAN.
In this way a node fetching only some entries belonging to
some VLANs is still able to compute the needed CRCs and
still check the table correctness.

With this patch the shape of the TVLV-TT is changed too
because now a node needs to advertise all the CRCs of all
the VLANs that it is wired to.

The debug output of the local Translation Table now shows
the CRC along with each entry since there is not a common
value for the entire table anymore.
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

A TT response may be prepared and sent while the local or
global translation table is getting updated.

The worst case is when one of the tables is accessed after
its content has been recently updated but the metadata
(TTVN/CRC) has not yet. In this case the reader will get a
table content which does not match the TTVN/CRC.
This will lead to an inconsistent state and so to a TT
recovery.

To avoid entering this situation, put a lock around those TT
operations recomputing the metadata and around the TT
Response creation (the latter is the only reader that
accesses the metadata together with the table).
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

this comment refers to the old batmand codebase and does
not make sense anymore. Remove it
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

With this patch the functions batadv_send_skb_unicast() and
batadv_send_skb_unicast_4addr() are further refined into
batadv_send_skb_via_tt(), batadv_send_skb_via_tt_4addr() and
batadv_send_skb_via_gw(). This way we avoid any "guessing" about where to send
a packet in the unicast forwarding methods and let the callers decide.

This is going to be useful for the upcoming multicast related patches in
particular.

Further, the return values were polished a little to use the more
appropriate NET_XMIT_* defines.
Signed-off-by: NLinus Lüssing <linus.luessing@web.de>
Acked-by: NAntonio Quartulli <antonio@meshcoding.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: NAntonio Quartulli <antonio@meshcoding.com>

AP isolation has to be enabled on one VLAN interface only.
This patch moves the AP isolation attribute to the per-vlan
interface attribute set, enabling it to have a different
value depending on the selected vlan.
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Each VLAN can now have its own set of attributes which are
exported through a new subfolder in the sysfs tree.
Each VLAN created on top of a soft_iface will have its own
subfolder.

The subfolder is named "vlan%VID" and it is created inside
the "mesh" sysfs folder belonging to batman-adv.

Attributes corresponding to the untagged LAN are stored in
the root sysfs folder as before.

This patch also creates all the needed macros and data
structures to easily handle new VLAN spacific attributes.
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Since batman-adv is now fully VLAN-aware, a proper framework
able to handle per-vlan-interface attributes is needed.

Those attributes will affect the associated VLAN interface
only, rather than the real soft_iface (which would result
in every vlan interface having the same attribute
configuration).

To make the code simpler and easier to extend, attributes
associated to the standalone soft_iface are now treated
like belonging to yet another vlan having a special vid.
This vid is different from the others because it is made up
by all zeros and the VLAN_HAS_TAG bit is not set.
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

The same IP subnet can be used on different VLANs, therefore
DAT has to differentiate whether the IP to resolve belongs
to one or the other virtual LAN.
To accomplish this task DAT has to deal with the VLAN tag
and store it together with each ARP entry.
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

The gateway code is now adapted in order to correctly
interact with the Translation Table component by using the
vlan ID
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

now that each TT entry is characterised by a VLAN ID, the
latter has to be taken into consideration when computing the
local/global table CRC as it would be theoretically possible
to have the same client in two different VLANs
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

To make the translation table code VLAN-aware, each entry
must carry the VLAN ID which it belongs to. This patch adds
such attribute to the related TT structures.
Signed-off-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>

Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: NAntonio Quartulli <antonio@meshcoding.com>

My university will stop email service for alumni in january 2014, please
use my new e-mail address instead.
Signed-off-by: NSimon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>

Fix bogus merge conflict resolution by checking the return
values of the skb preparation routines.
Signed-off-by: NAntonio Quartulli <antonio@meshcoding.com>

Randy found that if network namespace not enabled then
nd_net does not exist and would cause compilation failure.

This is handled correctly by using the dev_net() macro.
Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove the specialized code in __tcp_retransmit_skb() that tries to trim
any ACKed payload preceding a FIN before we retransmit (this was added
in 1999 in v2.2.3pre3). This trimming code was made unreachable by the
more general code added above it that uses tcp_trim_head() to trim any
ACKed payload, with or without a FIN (this was added in "[NET]: Add
segmentation offload support to TCP." in 2002 circa v2.5.33).
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Acked-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The rtmsg_fib function doesn't modify this argument so mark
it const.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current test works fine in practice.  The "amount" variable is
actually used as a boolean so negative values or any non-zero values
count as "true".  However since we don't allow numbers greater than one,
let's not allow negative numbers either.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>