Signed-off-by: Patrick McHardy <kaber@trash.net>

There is no reason for limiting netlink attributes in size.
Signed-off-by: Patrick McHardy <kaber@trash.net>

Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>

               |   NEW   | UPDATE  | DESTROY |
     ----------------------------------------|
     tuples    |    Y    |    Y    |    Y    |
     status    |    Y    |    Y    |    N    |
     timeout   |    Y    |    Y    |    N    |
     protoinfo |    S    |    S    |    N    |
     helper    |    S    |    S    |    N    |
     mark      |    S    |    S    |    N    |
     counters  |    F    |    F    |    Y    |

 Leyend:
         Y: yes
         N: no
         S: iif the field is set
	 F: iif overflow

This patch also replace IPCT_HELPINFO by IPCT_HELPER since we want to
track the helper assignation process, not the changes in the private
information held by the helper.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>

Check that status flags are available in the netlink message received
to create a new conntrack.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>

The NAT handling of the SIP helper has a few problems:

- Request headers are only mangled in the reply direction, From/To headers
  not at all, which can lead to authentication failures with DNAT in case
  the authentication domain is the IP address

- Contact headers in responses are only mangled for REGISTER responses

- Headers may be mangled even though they contain addresses not
  participating in the connection, like alternative addresses

- Packets are droppen when domain names are used where the helper expects
  IP addresses

This patch takes a different approach, instead of fixed rules what field
to mangle to what content, it adds symetric mapping of From/To/Via/Contact
headers, which allows to deal properly with echoed addresses in responses
and foreign addresses not belonging to the connection.
Signed-off-by: Patrick McHardy <kaber@trash.net>

Not every header has a shortcut, so make them optional instead
of searching for the same string twice.
Signed-off-by: Patrick McHardy <kaber@trash.net>

SIP headers are generally case-insensitive, only SDP headers are
case sensitive.
Signed-off-by: Patrick McHardy <kaber@trash.net>

- Use enum for header field enumeration
- Use numerical value instead of pointer to header info structure to
  identify headers, unexport ct_sip_hdrs
- group SIP and SDP entries in header info structure
- remove double forward declaration of ct_sip_get_info
Signed-off-by: Patrick McHardy <kaber@trash.net>

The NAT helpr hooks are protected by RCU, but all of the
conntrack helpers test and use the global pointers instead
of copying them first using rcu_dereference()

Also replace synchronize_net() by synchronize_rcu() for clarity
since sychronizing only with packet receive processing is
insufficient to prevent races.
Signed-off-by: Patrick McHardy <kaber@trash.net>

We usually uses 'xxx_find_get' for function which increments
reference count.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>

This patch adds /proc/net/ip_conntrack, /proc/net/ip_conntrack_expect and
/proc/net/stat/ip_conntrack files to keep old programs using them working.

The /proc/net/ip_conntrack and /proc/net/ip_conntrack_expect files show only
IPv4 entries, the /proc/net/stat/ip_conntrack shows global statistics.
Signed-off-by: Patrick McHardy <kaber@trash.net>

This patch adds an option to keep the connection tracking sysctls visible
under their old names.
Signed-off-by: Patrick McHardy <kaber@trash.net>

Signed-off-by: Patrick McHardy <kaber@trash.net>

Add helper functions for sysctl registration with optional instantiating
of common path elements (like net/netfilter) and use it for support for
automatic registation of conntrack protocol sysctls.
Signed-off-by: Patrick McHardy <kaber@trash.net>

Using extern in a C file is a bad idea because the compiler can't
catch type errors.
Signed-off-by: Patrick McHardy <kaber@trash.net>

Signed-off-by: Patrick McHardy <kaber@trash.net>

Only update the conntrack timer if there's been at least HZ jiffies since
the last update. Reduces the number of del_timer/add_timer cycles from one
per packet to one per connection per second (plus once for each state change
of a connection)

Should handle timer wraparounds and connection timeout changes.
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

Remove unused struct list_head from struct nf_conntrack_l3proto and
nf_conntrack_l4proto as all protocols are kept in arrays, not linked
lists.
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

Minor whitespace cleanup.
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

Remove the usage of ASSERT_READ_LOCK/ASSERT_WRITE_LOCK in nf_conntrack,
it didn't do anything, it was just an empty define and it uglified the code.
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

Add some more sanity checks when registering/unregistering l3/l4 protocols.
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

Rename 'struct nf_conntrack_protocol' to 'struct nf_conntrack_l4proto' in
order to help distinguish it from 'struct nf_conntrack_l3proto'. It gets
rather confusing with 'nf_conntrack_protocol'.
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

Place rarely written variables in the read-mostly section by using
__read_mostly
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

This patch splits out L3/L4 protocol handling into its own file
nf_conntrack_proto.c
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

This patch splits out the event cache into its own file
nf_conntrack_ecache.c
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

This patch splits out handling of helpers into its own file
nf_conntrack_helper.c
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

This patch splits out expectation handling into its own file
nf_conntrack_expect.c
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

This helps Vegas cope better with delayed ACKs, see
analysis at:

http://www.cs.caltech.edu/%7Eweixl/technical/ns2linux/known_linux/index.html#vegasSigned-off-by: David S. Miller <davem@davemloft.net>

This patch implements a suggestion by Ian McDonald and

 1) Avoids tests against negative packet lengths by using unsigned int
    for packet payload lengths in the CCID send_packet()/packet_sent() routines

 2) As a consequence, it removes an now unnecessary test with regard to `len > 0'
    in ccid3_hc_tx_packet_sent: that condition is always true, since
      * negative packet lengths are avoided
      * ccid3_hc_tx_send_packet flags an error whenever the payload length is 0.
        As a consequence, ccid3_hc_tx_packet_sent is never called as all errors
        returned by ccid_hc_tx_send_packet are caught in dccp_write_xmit

 3) Removes the third argument of ccid_hc_tx_send_packet (the `len' parameter),
    since it is currently always set to skb->len. The code is updated with regard
    to this parameter change.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

This implements the larger-initial-windows feature for CCID 3, as described in
section 5 of RFC 4342. When the first feedback packet arrives, the sender can
send up to 2..4 packets per RTT, instead of just one.

The patch further
 * reduces the number of timestamping calls by passing the timestamp value
   (which is computed in one of the calling functions anyway) as argument

 * renames one constant with a very long name into one which is shorter and
   resembles the one in RFC 3448 (t_mbi)

 * simplifies some of the min_t/max_t cases where both `x', `y' have the same
   type

Commiter note: renamed TFRC_t_mbi to TFRC_T_MBI, to follow Linux coding style.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

To reflect the fact that this now is of no effect, not making apps
stop working, just be warned in the system log.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

This removes and cleans up unused variables and structures which have become
unnecessary following the introduction of the EWMA patch to automatically track
the CCID 3 receiver/sender packet sizes `s'.

It deprecates the PACKET_SIZE socket option by returning an error code and
printing a deprecation warning if an application tries to read or write this
socket option.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

Problem:

This corrects the setting of the nofeedback timer with regard to RFC
3448 - previously it was not set to max(4*R, 2*s/X) as specified. Using
the maximum of 1 second as upper bound (as it was done before) can have
detrimental effects, especially if R is small.
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

This is in response to a request sent earlier by Eric W. Biederman
and replaces all sysctl numbers for net.dccp.default with CTL_UNNUMBERED.

It has been tested to compile and to work.

Commiter note: I've removed the use of CTL_UNNUMBERED, not setting .ctl_name
               sets it to 0, that is the what CTL_UNNUMBERED is, reason is
               to avoid unneeded source code cluttering.
Signed-off-by: Gerrit Renker  <gerrit@erg.abdn.ac.uk>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[acme@newtoy net-2.6.20]$ pahole /tmp/tcp_ipv6.o inet_protosw
/* /pub/scm/linux/kernel/git/acme/net-2.6.20/include/net/protocol.h:69 */
struct inet_protosw {
        struct list_head           list;                 /*     0     8 */
        short unsigned int         type;                 /*     8     2 */

        /* XXX 2 bytes hole, try to pack */

        int                        protocol;             /*    12     4 */
        struct proto *             prot;                 /*    16     4 */
        const struct proto_ops  *  ops;                  /*    20     4 */
        int                        capability;           /*    24     4 */
        char                       no_check;             /*    28     1 */
        unsigned char              flags;                /*    29     1 */
}; /* size: 32, sum members: 28, holes: 1, sum holes: 2, padding: 2 */

So that we can kill that hole, protocol can only go all the way to 255 (RAW).
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

As this struct is not userland visible at all.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

With this we eliminate the last hole in struct tcp_sock.

End result:

[acme@newtoy net-2.6.20]$ codiff -sV /tmp/tcp.o.before net/ipv4/tcp.o
/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv4/tcp.c:
  struct tcp_sock |   -4
    tcp_header_len;
     from: int                   /*  1000(0)     4(0) */
     to:   u16                   /*  1000(0)     2(0) */
 1 struct changed
[acme@newtoy net-2.6.20]$

Now sizeof(tcp_sock) is just...

[acme@newtoy net-2.6.20]$ pahole --sizes ../OUTPUT/qemu/net-2.6.20/net/ipv4/tcp.o | grep -w tcp_sock
struct tcp_sock: 1500 0

1500 bytes ;-)
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

This patch
 * removes setting t_RTO in ccid3_hc_tx_init (per [RFC 3448, 4.2], t_RTO is
   undefined until feedback has been received);

 * makes some trivial changes (updates of comments);

 * performs a small optimisation by exploiting that the feedback timeout
   uses the value of t_ipi. The way it is done is safe, because the timeouts
   appear after the changes to t_ipi, ensuring that up-to-date values are used;

 * in ccid3_hc_tx_packet_recv, moves the t_rto statement closer to the calculation
   of the next_tmout. This makes the code clearer to read and is also safe, since
   t_rto is not updated until the next call of ccid3_hc_tx_packet_recv, and is not
   read by the functions called via ccid_wait_for_ccid();

 * removes a `max' statement in sk_reset_timer, this is not needed since the timeout
   value is always greater than 1E6 microseconds.

 * adds `XXX'es to highlight that currently the nofeedback timer is set
   in a non-standard way
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>