[NET]: ipvs checksum annotations.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: IP header modifier helpers annotations.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Make mangling a checksum (0 -> 0xffff on the wire) explicit.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate __skb_checksum_complete() and friends.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate ip_vs_checksum_complete() and callers.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate skb_copy_and_csum_bits() and callers.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate skb_checksum() and callers.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate callers of the reset of checksum.h stuff.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate callers of csum_partial_copy_...() and csum_and_copy...() in net/*

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate csum_partial() callers in net/*

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: annotate csum_ipv6_magic() callers in net/*

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate csum_tcpudp_magic() callers in net/*

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate csum_tcpudp_magic() callers in net/*

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate callers of csum_tcpudp_nofold() in net/*

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate callers of csum_fold() in net/*

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate checksums in on-the-wire packets.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Generic checksum annotations and cleanups.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: XTENSA checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill csum_partial_copy_fromuser
* kill csum_partial_copy
* kill useless shifts
* usual ntohs->shift

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: SPARC64 checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill useless shift

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: SPARC checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill bogus access_ok() in csum_partial_copy_from_user (the only caller checks)
* kill useless shift

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: SH checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill useless shifts
* usual ntohs->shift

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: S390 checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill useless shifts

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: POWERPC checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill useless shifts

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: I386 checksum annotations and cleanups.

* sanitize prototypes, annotate
* usual ntohs->shift

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: AVR32 checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill useless shifts
* kill useless ntohs (it's big-endian, for fsck sake!)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: ARM26 checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill csum_partial_copy

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: ARM checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill csum_partial_copy
* usual ntohs->shift, this time in assembler part

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: X86_64 checksum annotations and cleanups.

* sanitize prototypes, annotate
* usual ntohs->shift

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: V850 checksum annotations and cleanups.

* sanitize prototypes, annotate
* collapse csum_partial_copy
* usual ntohs->shift

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: UML checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill csum_partial_copy_fromuser
* kill shift-by-16 in checksum calculations
* ntohs->shift in checksum calculations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: SH64 checksum annotations and cleanups.

* sanitize prototypes, annotate
* collapse csum_partial_copy
* kill csum_partial_copy_fromuser
* ntohs->shift in checksum calculation

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: PARISC checksum annotations and cleanups.

* sanitized prototypes, annotated
* kill shift-by-16 in checksum calculation

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: MIPS checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill shift-by-16 in checksum calculations
* htons->shift in l-e checksum calculations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: M68Knommu checksum annotations and cleanups.

* sanitize prototypes, annotated
* collapsed csum_partial_copy()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: M68K checksum annotations and cleanups.

* sanitize prototypes, annotate

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: M32R checksum annotations and cleanups.

* sanitize prototypes, annotate
* ntohs -> shift in checksum calculations in l-e case
* kill shift-by-16 in checksum calculations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: IA64 checksum annotations and cleanups.

* sanitize prototypes, annotate
* ntohs -> shift in checksum calculations
* kill access_ok() in csum_partial_copy_from_user
* collapse do_csum_partial_copy_from_user

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: H8300 checksum annotations and cleanups.

* sanitize prototypes and annotate
* collapse csum_partial_copy

NB: csum_partial() is almost certainly still buggy.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: FRV checksum annotations.

* sanitize prototypes and annotate
* collapse csum_partial_copy

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Cris checksum annotations and cleanups.

* sanitize prototypes and annotate
* kill cast-as-lvalue abuses in csum_partial()
* usual ntohs-equals-shift for checksum purposes

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Alpha checksum annotations and cleanups.

* sanitize prototypes and annotate
* kill useless access_ok() in csum_partial_copy_from_user() (the only
caller checks it already).
* do_csum_partial_copy_from_user() is not needed now
* replace htons(len) with len << 8 - they are the same wrt checksums
on little-endian.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Introduce types for checksums.

New types - for 16bit checksums and "unfolded" 32bit variant.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Kill direct includes of asm/checksum.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[IPVS]: Annotate ..._app_hashkey().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Annotate net_srandom().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[BRIDGE]: Annotations.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[ATM]: Annotations.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: More trivial annotations.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[IPV6]: __ipv6_addr_diff() annotations and cleanup.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[IPV6]: Misc endianness annotations.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[RANDOM]: Annotate random.h IP helpers.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[IPV6]: Assorted trivial endianness annotations.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET] net/core: Annotations.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[IRDA]: Trivial annotations.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETPOLL]: Minor coding-style cleanups.

Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Supporting UDP-Lite (RFC 3828) in Linux

This is a revision of the previously submitted patch, which alters
the way files are organized and compiled in the following manner:

* UDP and UDP-Lite now use separate object files
* source file dependencies resolved via header files
  net/ipv{4,6}/udp_impl.h
* order of inclusion files in udp.c/udplite.c adapted
  accordingly

[NET/IPv4]: Support for the UDP-Lite protocol (RFC 3828)

This patch adds support for UDP-Lite to the IPv4 stack, provided as an
extension to the existing UDPv4 code:
        * generic routines are all located in net/ipv4/udp.c
        * UDP-Lite specific routines are in net/ipv4/udplite.c
        * MIB/statistics support in /proc/net/snmp and /proc/net/udplite
        * shared API with extensions for partial checksum coverage

[NET/IPv6]: Extension for UDP-Lite over IPv6

It extends the existing UDPv6 code base with support for UDP-Lite
in the same manner as per UDPv4. In particular,
        * UDPv6 generic and shared code is in net/ipv6/udp.c
        * UDP-Litev6 specific extensions are in net/ipv6/udplite.c
        * MIB/statistics support in /proc/net/snmp6 and /proc/net/udplite6
        * support for IPV6_ADDRFORM
        * aligned the coding style of protocol initialisation with af_inet6.c
        * made the error handling in udpv6_queue_rcv_skb consistent;
          to return `-1' on error on all error cases
        * consolidation of shared code

[NET]: UDP-Lite Documentation and basic XFRM/Netfilter support

The UDP-Lite patch further provides
        * API documentation for UDP-Lite
        * basic xfrm support
        * basic netfilter support for IPv4 and IPv6 (LOG target)

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[IPv6] prefix: Convert RTM_NEWPREFIX notifications to use the new netlink api

RTM_GETPREFIX is completely unused and is thus removed.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

[IPv6] iflink: Convert IPv6's RTM_GETLINK to use the new netlink api

By replacing the current method of exporting the device configuration
which included allocating a temporary buffer, copying ipv6_devconf
into it and copying that buffer into the message with a method that
uses nla_reserve() allowing to copy the device configuration directly
into the skb data buffer, a GFP_ATOMIC allocation could be removed.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

[TCP]: Fix some warning when MD5 is disabled.

Just some mis-placed ifdefs:

net/ipv4/tcp_minisocks.c: In function ‘tcp_twsk_destructor’:
net/ipv4/tcp_minisocks.c:364: warning: unused variable ‘twsk’
net/ipv6/tcp_ipv6.c:1846: warning: ‘tcp_sock_ipv6_specific’ defined but not used
net/ipv6/tcp_ipv6.c:1877: warning: ‘tcp_sock_ipv6_mapped_specific’ defined but not used

Signed-off-by: David S. Miller <davem@davemloft.net>

[GENL]: Add genlmsg_put_reply() to simplify building reply headers

By modyfing genlmsg_put() to take a genl_family and by adding
genlmsg_put_reply() the process of constructing the netlink
and generic netlink headers is simplified.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[GENL]: Add genlmsg_reply() to simply unicast replies to requests

A generic netlink user has no interest in knowing how to
address the source of the original request.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[GENL]: Add genlmsg_new() to allocate generic netlink messages

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[TCP]: MD5 Signature Option (RFC2385) support.

Based on implementation by Rick Payne.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netpoll header cleanup

As Steve left netpoll beast, hopefully not to return soon.
He noticed that the header was messy. He straightened it
up and polished it a little, then waved goodbye.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>

netpoll queue cleanup

The beast had a long and not very happy history. At one
point, a friend (netdump) had asked that he open up a little.
Well, the friend was long gone now, and the beast had
this dangling piece hanging (netpoll_queue).

It wasn't hard to stitch the netpoll_queue back in
where it belonged and make everything tidy.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>

netpoll retry cleanup

The netpoll beast was still not happy. If the beast got
clogged pipes, it tended to stare blankly off in space
for a long time.

The problem couldn't be completely fixed because the
beast talked with irq's disabled. But it could be made
less painful and shorter.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>

netpoll deferred transmit path

When the netpoll beast got busy, he tended to babble.
Instead of talking out of his large mouth as normal,
he tended to try to snort out other orifices. This lead
to words (skbs) ending up in odd places (like NIT) that
he did not intend.

The normal way of talking wouldn't work, but he could
at least change to using the same tone all the time.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>

netpoll setup error handling

The beast was not always healthy. When it was sick,
it tended to be laconic and not tell anyone the real problem.
A few small changes had it telling the world about its
problems, if they really wanted to hear.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>

netpoll per device txq

When the netpoll beast got really busy, it tended to clog
things, so it stored them for later. But the beast was putting
all it's skb's in one basket. This was bad because maybe some
pipes were clogged and others were not.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>

netpoll info leak

After looking harder, Steve noticed that the netpoll
beast leaked a little every time it shutdown for a nap.
Not a big leak, but a nuisance kind of thing.

He took out his refcount duct tape and patched the
leak. It was overkill since there was already other
locking in that area, but it looked clean and wouldn't
attract fleas.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>

netpoll: private skb pool (rev3)

It was a dark and stormy night when Steve first saw the
netpoll beast. The beast was odd, and misshapen but not
extremely ugly.

"Let me take off one of your warts" he said. This wart
is where you tried to make an skb list yourself. If the
beast had ever run out of memory, he would have stupefied
himself unnecessarily.

The first try was painful, so he tried again till the bleeding
stopped. And again, and again...

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>

[DCCP] ACKVEC: Optimization - Do not traverse records if none will be found

Do not traverse the list of ack vector records [proportional to window size]
when we know we will not find what we are looking for.  This is especially
useful because ack vectors are checked twice:
1) Upon parsing of options.
2) Upon notification of a new ack.

All of the work will occur during check #1.  Therefore, when check #2 is
performed, no new work will be done.  This is now "detected" and there is no
performance hit when doing #2.

Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[DCCP]: Miscellaneous code tidy-ups

This patch does not change code; it performs some trivial clean/tidy-ups:

  * removal of a `debug_prefix' string in favour of the
    already existing dccp_role(sk)

  * add documentation of structures and constants

  * separated out the cases for invalid packets (step 1
    of the packet validation)

  * removing duplicate statements

  * combining declaration & initialisation

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[DCCP]: Make feature negotiation more readable

This patch replaces cryptic feature negotiation messages of type

Oct 31 15:42:20 kernel: dccp_feat_change: feat change type=32 feat=1
Oct 31 15:42:21 kernel: dccp_feat_change: feat change type=34 feat=1
Oct 31 15:42:21 kernel: dccp_feat_change: feat change type=32 feat=5

into ones of type:

Nov  2 13:54:45 kernel: dccp_feat_change: ChangeL(CCID (1), 3)
Nov  2 13:54:45 kernel: dccp_feat_change: ChangeR(CCID (1), 3)
Nov  2 13:54:45 kernel: dccp_feat_change: ChangeL(Ack Ratio (5), 2)

Also,
* completed the feature number list wrt RFC 4340 sec. 6.4
* annotating which ones have been implemented so far
* implemented rudimentary sanity checking in feat.c (FIXMEs)
* some minor fixes

Commiter note: uninlined dccp_feat_name and dccp_feat_typename, for
               consistency with dccp_{state,packet}_name, that, BTW,
               should be compiled only if CONFIG_IP_DCCP_DEBUG is
               selected, leaving this to another cset tho. Also
               shortened dccp_feat_negotiation_debug to dccp_feat_debug.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[DCCPv6]: Resolve conditional build problem

Resolves the problem that if IPv6 was configured `y' and DCCP `m' then
dccp_ipv6 was not built as a module. With this change, dccp_ipv6 is built
as a module whenever DCCP *OR* IPv6 are configured as modules; it will be
built-in only if both DCCP = `y' and IPV6 = `y'.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[TCP/DCCP]: Introduce net_xmit_eval

Throughout the TCP/DCCP (and tunnelling) code, it often happens that the
return code of a transmit function needs to be tested against NET_XMIT_CN
which is a value that does not indicate a strict error condition.

This patch uses a macro for these recurring situations which is consistent
with the already existing macro net_xmit_errno, saving on duplicated code.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[SCTP]: Cleanup of the sctp state table code.

I noticed an insane high density of repeated characters fixable by a
simple regular expression:

  % s/{.fn = \([^,]*\),[[:space:]]\+\(\\\n[[:space:]]\+\)\?.name = "\1"}/TYPE_SCTP_FUNC(\1)/g

(NOTE: the .name for .fn = sctp_sf_do_9_2_start_shutdown didn't match)

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>

[ATM] ambassador,firestream: "-1 >>" is implementation defined

6.5.7(5): The result of E1 >> E2 is E1 right-shifted E2 bit positions.
...
If E1 has a signed type and a negative value, the resulting value
is implementation defined.

So, cast -1 to unsigned type to make result well-defined.

[ Modified to use ~0U based upon recommendation from Al Viro. -DaveM ]

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SELinux]: Add support for DCCP

This patch implements SELinux kernel support for DCCP
(http://linux-net.osdl.org/index.php/DCCP), which is similar in
operation to TCP in terms of connected state between peers.

The SELinux support for DCCP is thus modeled on existing handling of
TCP.

A new DCCP socket class is introduced, to allow protocol
differentation.  The permissions for this class inherit all of the
socket permissions, as well as the current TCP permissions (node_bind,
name_bind etc). IPv4 and IPv6 are supported, although labeled
networking is not, at this stage.

Patches for SELinux userspace are at:
http://people.redhat.com/jmorris/selinux/dccp/user/

I've performed some basic testing, and it seems to be working as
expected.  Adding policy support is similar to TCP, the only real
difference being that it's a different protocol.

Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: The scheduled removal of the frame diverter.

This patch contains the scheduled removal of the frame diverter.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

[DCCPv6]: Choose a genuine initial sequence number

This
* resolves a FIXME - DCCPv6 connections started all with
  an initial sequence number of 1;
* provides a redirection `secure_dccpv6_sequence_number'
  in case the init_sequence_v6 code should be updated later;
* concentrates the update of S.GAR into dccp_connect_init();
* removes a duplicate dccp_update_gss() in ipv4.c;
* uses inet->dport instead of usin->sin_port, due to the
  following assignment in dccp_v4_connect():
  inet->dport = usin->sin_port;

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[DCCP]: Remove redundant statements in init_sequence (ISS)

This patch removes the following redundancies:

 1) The test skb->protocol == htons(ETH_P_IPV6) in dccp_v6_init_sequence
    is always true since
     * dccp_v6_conn_request() is the only calling function
     * dccp_v6_conn_request() redirects all skb's with ETH_P_IP to
       dccp_v4_conn_request()

 2) The first argument, `struct sock *sk', of dccp_v{4,6}_init_sequence()
    is never used.

(This is similar for tcp_v{4,6}_init_sequence, an analogous patch has been
 submitted to netdev and merged.)

By the way - are the `sport' / `dport' arguments in the right order?
I have made them consistent among calls but they seem to be in the
reverse order.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[DCCP]: Remove forward declarations in timer.c

This removes 3 forward declarations by reordering 2 functions.

No code change at all.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[DCCP]: Introduce a consistent naming scheme for sysctls

In order to make their function clearer and obtain a consistent naming
scheme to identify sysctls, all existing DCCP sysctls have been prefixed
with `sysctl_dccp', following the same convention as used by TCP.

Feature-specific sysctls retain the `feat' in the middle, although the
`default' has been dropped, since it is obvious from use.

Also removed a duplicate `dccp_feat_default_sequence_window' in ipv4.c.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[DCCP]: Add sysctls to control retransmission behaviour

This adds 3 sysctls which govern the retransmission behaviour of DCCP control
packets (3way handshake, feature negotiation).

It removes 4 FIXMEs from the code.

The close resemblance of sysctl variables to their TCP analogues is emphasised
not only by their name, but also by giving them the same initial values.
This is useful since there is not much practical experience with DCCP yet.

Furthermore, with regard to the previous patch, it is now possible to limit
the number of keepalive-Responses by setting net.dccp.default.request_retries
(also a bit like in TCP).

Lastly, added documentation of all existing DCCP sysctls.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[DCCP]: Increment sequence numbers on retransmitted Response packets

Problem:

[DCCP]: Update comments on precisely which packets can be retransmitted

This updates program documentation: spell out precise conditions about
which packets are eligible for retransmission (which is actually quite
hard to extract from RFC 4340).

It is based on the following table derived from RFC 4340:

+-----------+---------------------------------+---------------------+
|   Type    | Retransmit?                     |  Remark             |
+-----------+---------------------------------+---------------------+
| Request   |  in client-REQUEST state        | sec. 8.1.1          |
| Response  |  NEVER                          | SHOULD NOT, 8.1.3   |
| Data      |  NEVER                          | unreliable protocol |
| Ack       |  possible in client-PARTOPEN    | sec. 8.1.5          |
| DataAck   |  NEVER                          | unreliable protocol |
| CloseReq  |  only in server-CLOSEREQ state  | MUST, sec. 8.3      |
| Close     |  in node-CLOSING state          | MUST, sec. 8.3      |
+-----------+-------------------------------------------------------+
| Reset     |  only in response to other packets                    |
| Sync      |  only in response to sequence-invalid packets (7.5.4) |
| SyncAck   |  only in response to Sync packets                     |
+-----------+-------------------------------------------------------+

Hence the only packets eligible for retransmission are:
       * Requests in client-REQUEST  state (sec. 8.1.1)
       * Acks     in client-PARTOPEN state (sec. 8.1.5)
       * CloseReq in server-CLOSEREQ state (sec. 8.3)
       * Close    in   node-CLOSING  state (sec. 8.3)

I had meant to put in a check for these types too, but have left that
for later.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[DECNET]: Fix build regressions.

Spotted by Arnaldo.

Signed-off-by: David S. Miller <davem@davemloft.net>

[TCP] htcp: Better packing of struct htcp.

Based upon a patch by Joe Perches.

Signed-off-by: David S. Miller <davem@davemloft.net>

[IPv6]: Only modify checksum for UDP

Only change upper-layer checksum from 0 to 0xFFFF for UDP (as RFC 768
states), not for others as RFC 4443 doesn't require it.

Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[IPv6] rules: Remove bogus tos validation check

Noticed by Al Viro:
     (frh->tos & ~IPV6_FLOWINFO_MASK))
where IPV6_FLOWINFO_MASK is htonl(0xfffffff) and frh->tos
is u8, which makes no sense here...

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETLINK]: Do precise netlink message allocations where possible

Account for the netlink message header size directly in nlmsg_new()
instead of relying on the caller calculate it correctly.

Replaces error handling of message construction functions when
constructing notifications with bug traps since a failure implies
a bug in calculating the size of the skb.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[TCP]: Remove dead code in init_sequence

This removes two redundancies:

1) The test (skb->protocol == htons(ETH_P_IPV6) in tcp_v6_init_sequence()
   is always true, due to
* tcp_v6_conn_request() is the only function calling this one
* tcp_v6_conn_request() redirects all skb's with ETH_P_IP protocol to
  tcp_v4_conn_request() [ cf. top of tcp_v6_conn_request()]

2) The first argument, `struct sock *sk' of tcp_v{4,6}_init_sequence() is
   never used.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[DCCP]: Support for partial checksums (RFC 4340, sec. 9.2)

This patch does the following:
  a) introduces variable-length checksums as specified in [RFC 4340, sec. 9.2]
  b) provides necessary socket options and documentation as to how to use them
  c) basic support and infrastructure for the Minimum Checksum Coverage feature
     [RFC 4340, sec. 9.2.1]: acceptability tests, user notification and user
     interface

In addition, it

 (1) fixes two bugs in the DCCPv4 checksum computation:
  * pseudo-header used checksum_len instead of skb->len
* incorrect checksum coverage calculation based on dccph_x
 (2) removes dccp_v4_verify_checksum() since it reduplicates code of the
     checksum computation; code calling this function is updated accordingly.
 (3) now uses skb_checksum(), which is safer than checksum_partial() if the
     sk_buff has is a non-linear buffer (has pages attached to it).
 (4) fixes an outstanding TODO item:
        * If P.CsCov is too large for the packet size, drop packet and return.

The code has been tested with applications, the latest version of tcpdump now
comes with support for partial DCCP checksums.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[IPV6]: Per-interface statistics support.

For IP MIB (RFC4293).

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

[IPV6]: Introduce ip6_dst_idev() to get inet6_dev{} stored in dst_entry{}.

Otherwise, we will see a lot of casts...

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

[IPV6] ROUTE: Use &rt->u.dst instead of cast.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

[IPV6] ROUTE: Use macros to format /proc/net/ipv6_route.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

[DCCP]: Update code comments for Step 2/3

Sorts out the comments for processing steps 2,3 in section 8.5 of RFC 4340.
All comments have been updated against this document, and the reference to step
2 has been made consistent throughout the files.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[DCCP]: tidy up dccp_v{4,6}_conn_request

This is a code simplification to remove reduplicated code
by concentrating and abstracting shared code.

Detailed Changes: