Old space allocator of conntrack had problems about extensibility.
- It required slab cache per combination of extensions.
- It expected what extensions would be assigned, but it was impossible
  to expect that completely, then we allocated bigger memory object than
  really required.
- It needed to search helper twice due to lock issue.

Now basic informations of a connection are stored in 'struct nf_conn'.
And a storage for extension (helper, NAT) is allocated by kmalloc.
Signed-off-by: NYasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The TRACE target can be used to follow IP and IPv6 packets through
the ruleset.
Signed-off-by: NJozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: NPatrick NcHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Along comes... xt_u32, a revamped ipt_u32 from POM-NG,
Plus:

    *	2007-06-02: added ipv6 support

    *	2007-06-05: uses kmalloc for the big buffer

    *   2007-06-05: added inversion

    *   2007-06-20: use skb_copy_bits() and get rid of the big buffer
        and lock (suggested by Pablo Neira Ayuso)
Signed-off-by: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Removes redundant parentheses and braces (And add one pair in a
xt_tcpudp.c macro).
Signed-off-by: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make a number of variables const and/or remove unneeded casts.
Signed-off-by: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Switch the return type of target checkentry functions to boolean.
Signed-off-by: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Switch the return type of match functions to boolean
Signed-off-by: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Switch the return type of match functions to boolean
Signed-off-by: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Switch the "hotdrop" variables to boolean
Signed-off-by: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Check range before checking STOP flag. This optimization may save a
nanosecond or less :)
Signed-off-by: NJing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently NAT (and others) that want to modify cloned skbs copy them,
even if in the vast majority of cases its not necessary because the
skb is a clone made by TCP and the portion NAT wants to modify is
actually writable because TCP release the header reference before
cloning.

The problem is that there is no clean way for NAT to find out how
long the writable header area is, so this patch introduces skb->hdr_len
to hold this length. When a headerless skb is cloned skb->hdr_len
is set to the current headroom, for regular clones it is copied from
the original. A new function skb_clone_writable(skb, len) returns
whether the skb is writable up to len bytes from skb->data. To avoid
enlarging the skb the mac_len field is reduced to 16 bit and the
new hdr_len field is put in the remaining 16 bit.

I've done a few rough benchmarks of NAT (not with this exact patch,
but a very similar one). As expected it saves huge amounts of system
time in case of sendfile, bringing it down to basically the same
amount as without NAT, with sendmsg it only helps on loopback,
probably because of the large MTU.

Transmit a 1GB file using sendfile/sendmsg over eth0/lo with and
without NAT:

- sendfile eth0, no NAT:	sys     0m0.388s
- sendfile eth0, NAT:		sys     0m1.835s
- sendfile eth0: NAT + path:	sys     0m0.370s	(~ -80%)

- sendfile lo, no NAT:		sys     0m0.258s
- sendfile lo, NAT:		sys     0m2.609s
- sendfile lo, NAT + patch:	sys     0m0.260s	(~ -90%)

- sendmsg eth0, no NAT:		sys     0m2.508s
- sendmsg eth0, NAT:		sys     0m2.539s
- sendmsg eth0, NAT + patch:	sys     0m2.445s	(no change)

- sendmsg lo, no NAT:		sys	0m2.151s
- sendmsg lo, NAT:		sys     0m3.557s
- sendmsg lo, NAT + patch:	sys     0m2.159s	(~ -40%)

I expect other users can see a similar performance improvement,
packet mangling iptables targets, ipip and ip_gre come to mind ..
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Choices' index values may be out of range while still encoded in the fixed
length bit-field. This bug may cause access to undefined types (NULL
pointers) and thus crashes (Reported by Zhongling Wen).

This patch also adds checking of decode flag when decoding SEQUENCEs.
Signed-off-by: NJing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no realistic situation to change helper (Who wants IRC helper to
track FTP traffic ?). Moreover, if we want to do that, we need to fix race
issue by nfctnetlink and running helper. That will add overhead to packet
processing. It wouldn't pay. So this rejects the request to change
helper. The requests to add or remove helper are accepted as ever.
Signed-off-by: NYasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJerome Borsboom <j.borsboom@erasmusmc.nl>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The return value from textsearch_prepare() needs to be checked
by IS_ERR(). Because it returns error code as a pointer.

Cc: "Brian J. Murrell" <netfilter@interlinx.bc.ca>
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a helper module is unloaded all conntracks refering to it have their
helper pointer NULLed out, leading to lots of races. In most places this
can be fixed by proper use of RCU (they do already check for != NULL,
but in a racy way), additionally nf_conntrack_expect_related needs to
bail out when no helper is present.

Also remove two paranoid BUG_ONs in nf_conntrack_proto_gre that are racy
and not worth fixing.
Signed-off-by: NPatrick McHarrdy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add missing process of T.120 address in OpenLogicalChannelAck signal.
Signed-off-by: NJing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

According to the implementation of H.323, it's not necessary to check
the addresses in Information signals.
Signed-off-by: NJing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Update get_h225_addr() to meet the changes in ASN.1 types. It was using
field ip6 to access IPv6 TransportAddress, it should be ip according the
ASN.1 definition.
Signed-off-by: NJing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

1. Add support for decoding IPv6 address. I know it was manually added in
   the header file, but not in the template file. That wouldn't work.
2. Add missing support for decoding T.120 address in OLCA.
3. Remove unnecessary decoding of Information signal.
Signed-off-by: NJing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the packet size is changed by the FTP NAT helper, the connection
tracking helper adjusts the sequence number of the newline character
by the size difference. This is wrong because NAT sequence number
adjustment happens after helpers are called, so the unadjusted number
is compared to the already adjusted one.

Based on report by YU, Haitao <yuhaitao@tsinghua.org.cn>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When trying to locate the oldest entry in the history of newline character
sequence numbers, the sequence number of the current entry is incorrectly
compared with the index of the oldest sequence number instead of the number
itself.

Additionally it is not made sure that the current sequence number really
is after the oldest known one.

Based on report by YU, Haitao <yuhaitao@tsinghua.org.cn>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the helper module is removed for a master connection that has a
fulfilled expectation, but has already timed out and got removed from
the hash tables, nf_conntrack_helper_unregister can't find the master
connection to unset the helper, causing a use-after-free when the
expected connection is destroyed and releases the last reference to
the master.

The helper destroy callback was introduced for the PPtP helper to clean
up expectations and expected connections when the master connection
times out, but doing this from destroy_conntrack only works for
unfulfilled expectations since expected connections hold a reference
to the master, preventing its destruction. Move the destroy callback to
the timeout function, which fixes both problems.

Reported/tested by Gabor Burjan <buga@buvoshetes.hu>.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some helpers (eg. ftp) assume that private area in conntrack is
filled with zero. It should be cleared when helper is changed.
Signed-off-by: NYasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch
- Clears private area for helper even if no helper is assigned to
  conntrack. It might be used by old helper.
- Unchanges if the same helper as the used one is specified.
- Does not find helper if no helper is specified. And it does not
  require private area for helper in that case.
Signed-off-by: NYasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NYasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NMichael Opdenacker <michael@free-electrons.com>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

Fix several typos in help text in Kconfig* files.
Signed-off-by: NDavid Sterba <dave@jikos.cz>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

Documentation/modules.txt doesn't exist, but
Documentation/kbuild/modules.txt does.

Signed-off-by: Alexander E. Patrakov
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

- make the following needlessly global variables static:
  - core/rtnetlink.c: struct rtnl_msg_handlers[]
  - netfilter/nf_conntrack_proto.c: struct nf_ct_protos[]
- make the following needlessly global functions static:
  - core/rtnetlink.c: rtnl_dump_all()
  - netlink/af_netlink.c: netlink_queue_skip()
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Switch cb_lock to mutex and allow netlink kernel users to override it
with a subsystem specific mutex for consistent locking in dump callbacks.
All netlink_dump_start users have been audited not to rely on any
side-effects of the previously used spinlock.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't fallback to group 0 if no instance can be found for the given group.
This potentially confuses the listener and is not what the user configured.
Also remove the ring buffer spamming that happens when rules are set up
before the logging daemon is started.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To clearly state the intent of copying to linear sk_buffs, _offset being a
overly long variant but interesting for the sake of saving some bytes.
Signed-off-by: NArnaldo Carvalho de Melo <acme@ghostprotocols.net>

Patrick has made use of netlink_run_queue() in nfnetlink while my patches
have been waiting for net-2.6.22 to open. So this check for NLM_F_REQUEST
can go as well.
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The destructor per conntrack is unnecessary, then this replaces it with
system wide destructor.
Signed-off-by: NYasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NYasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is gross, have the wrapper function take the lock.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>