linux-stable.git/include/linux/netfilter_ipv6.h, branch v4.1.2

netfilter: Remove extern from function prototypes

2013-09-26T21:48:15+00:00

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: Joe Perches

netfilter: add nf_ipv6_ops hook to fix xt_addrtype with IPv6

2013-05-23T09:58:55+00:00

Quoting https://bugzilla.netfilter.org/show_bug.cgi?id=812:

[ ip6tables -m addrtype ]
When I tried to use in the nat/PREROUTING it messes up the
routing cache even if the rule didn't matched at all.
[..]
If I remove the --limit-iface-in from the non-working scenario, so just
use the -m addrtype --dst-type LOCAL it works!

This happens when LOCAL type matching is requested with --limit-iface-in,
and the default ipv6 route is via the interface the packet we test
arrived on.

Because xt_addrtype uses ip6_route_output, the ipv6 routing implementation
creates an unwanted cached entry, and the packet won't make it to the
real/expected destination.

Silently ignoring --limit-iface-in makes the routing work but it breaks
rule matching (--dst-type LOCAL with limit-iface-in is supposed to only
match if the dst address is configured on the incoming interface;
without --limit-iface-in it will match if the address is reachable
via lo).

The test should call ipv6_chk_addr() instead.  However, this would add
a link-time dependency on ipv6.

There are two possible solutions:

1) Revert the commit that moved ipt_addrtype to xt_addrtype,
   and put ipv6 specific code into ip6t_addrtype.
2) add new "nf_ipv6_ops" struct to register pointers to ipv6 functions.

While the former might seem preferable, Pablo pointed out that there
are more xt modules with link-time dependeny issues regarding ipv6,
so lets go for 2).

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

UAPI: (Scripted) Disintegrate include/linux

2012-10-13T09:46:48+00:00

Signed-off-by: David Howells 
Acked-by: Arnd Bergmann 
Acked-by: Thomas Gleixner 
Acked-by: Michael Kerrisk 
Acked-by: Paul E. McKenney 
Acked-by: Dave Jones

netfilter: add user-space connection tracking helper infrastructure

2012-06-16T13:40:02+00:00

There are good reasons to supports helpers in user-space instead:

* Rapid connection tracking helper development, as developing code
  in user-space is usually faster.

* Reliability: A buggy helper does not crash the kernel. Moreover,
  we can monitor the helper process and restart it in case of problems.

* Security: Avoid complex string matching and mangling in kernel-space
  running in privileged mode. Going further, we can even think about
  running user-space helpers as a non-root process.

* Extensibility: It allows the development of very specific helpers (most
  likely non-standard proprietary protocols) that are very likely not to be
  accepted for mainline inclusion in the form of kernel-space connection
  tracking helpers.

This patch adds the infrastructure to allow the implementation of
user-space conntrack helpers by means of the new nfnetlink subsystem
`nfnetlink_cthelper' and the existing queueing infrastructure
(nfnetlink_queue).

I had to add the new hook NF_IP6_PRI_CONNTRACK_HELPER to register
ipv[4|6]_helper which results from splitting ipv[4|6]_confirm into
two pieces. This change is required not to break NAT sequence
adjustment and conntrack confirmation for traffic that is enqueued
to our user-space conntrack helpers.

Basic operation, in a few steps:

1) Register user-space helper by means of `nfct':

 nfct helper add ftp inet tcp

 [ It must be a valid existing helper supported by conntrack-tools ]

2) Add rules to enable the FTP user-space helper which is
   used to track traffic going to TCP port 21.

For locally generated packets:

 iptables -I OUTPUT -t raw -p tcp --dport 21 -j CT --helper ftp

For non-locally generated packets:

 iptables -I PREROUTING -t raw -p tcp --dport 21 -j CT --helper ftp

3) Run the test conntrackd in helper mode (see example files under
   doc/helper/conntrackd.conf

 conntrackd

4) Generate FTP traffic going, if everything is OK, then conntrackd
   should create expectations (you can check that with `conntrack':

 conntrack -E expect

    [NEW] 301 proto=6 src=192.168.1.136 dst=130.89.148.12 sport=0 dport=54037 mask-src=255.255.255.255 mask-dst=255.255.255.255 sport=0 dport=65535 master-src=192.168.1.136 master-dst=130.89.148.12 sport=57127 dport=21 class=0 helper=ftp
[DESTROY] 301 proto=6 src=192.168.1.136 dst=130.89.148.12 sport=0 dport=54037 mask-src=255.255.255.255 mask-dst=255.255.255.255 sport=0 dport=65535 master-src=192.168.1.136 master-dst=130.89.148.12 sport=57127 dport=21 class=0 helper=ftp

This confirms that our test helper is receiving packets including the
conntrack information, and adding expectations in kernel-space.

The user-space helper can also store its private tracking information
in the conntrack structure in the kernel via the CTA_HELP_INFO. The
kernel will consider this a binary blob whose layout is unknown. This
information will be included in the information that is transfered
to user-space via glue code that integrates nfnetlink_queue and
ctnetlink.

Signed-off-by: Pablo Neira Ayuso

headers, netfilter: Add missing #include for userland

2011-08-26T16:02:50+00:00

Various headers use INT_MIN and INT_MAX, which are defined for
userland in .

Signed-off-by: Ben Hutchings 
Acked-by: Patrick McHardy 
Signed-off-by: David S. Miller

netfilter: ip6table_raw: fix table priority

2010-03-25T10:17:26+00:00

The order of the IPv6 raw table is currently reversed, that makes impossible
to use the NOTRACK target in IPv6: for example if someone enters

ip6tables -t raw -A PREROUTING -p tcp --dport 80 -j NOTRACK

and if we receive fragmented packets then the first fragment will be
untracked and thus skip nf_ct_frag6_gather (and conntrack), while all
subsequent fragments enter nf_ct_frag6_gather and reassembly will never
successfully be finished.

Singed-off-by: Jozsef Kadlecsik 
Signed-off-by: Patrick McHardy

netfilter: cleanup netfilter_ipv6.h userspace header

2008-07-08T09:36:40+00:00

Kernel functions are not for userspace.

Signed-off-by: Adrian Bunk 
Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller

netfilter: ip6_tables: add ip6tables security table

2008-06-09T22:58:05+00:00

This is a port of the IPv4 security table for IPv6.

Signed-off-by: James Morris 
Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller

[NETFILTER]: Introduce NF_INET_ hook values

2008-01-28T22:53:55+00:00

The IPv4 and IPv6 hook values are identical, yet some code tries to figure
out the "correct" value by looking at the address family. Introduce NF_INET_*
values for both IPv4 and IPv6. The old values are kept in a #ifndef __KERNEL__
section for userspace compatibility.

Signed-off-by: Patrick McHardy 
Acked-by: Herbert Xu 
Signed-off-by: David S. Miller

[NETFILTER]: bridge-netfilter: remove deferred hooks

2006-12-14T00:54:25+00:00

Remove the deferred hooks and all related code as scheduled in
feature-removal-schedule.

Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller