linux.git/include/uapi/linux/netfilter, branch v4.2

netfilter: xt_socket: add XT_SOCKET_RESTORESKMARK flag

2015-06-18T11:05:09+00:00

xt_socket is useful for matching sockets with IP_TRANSPARENT and
taking some action on the matching packets. However, it lacks the
ability to match only a small subset of transparent sockets.

Suppose there are 2 applications, each with its own set of transparent
sockets. The first application wants all matching packets dropped,
while the second application wants them forwarded somewhere else.

Add the ability to retore the skb->mark from the sk_mark. The mark
is only restored if a matching socket is found and the transparent /
nowildcard conditions are satisfied.

Now the 2 hypothetical applications can differentiate their sockets
based on a mark value set with SO_MARK.

iptables -t mangle -I PREROUTING -m socket --transparent \
                                           --restore-skmark -j action
iptables -t mangle -A action -m mark --mark 10 -j action2
iptables -t mangle -A action -m mark --mark 11 -j action3

Signed-off-by: Harout Hedeshian 
Signed-off-by: Pablo Neira Ayuso

netfilter: nfnetlink_queue: add security context information

2015-06-18T11:02:24+00:00

This patch adds an additional attribute when sending
packet information via netlink in netfilter_queue module.
It will send additional security context data, so that
userspace applications can verify this context against
their own security databases.

Signed-off-by: Roman Kubiak 
Acked-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: attach net_device to basechain

2015-06-15T21:02:31+00:00

The device is part of the hook configuration, so instead of a global
configuration per table, set it to each of the basechain that we create.

This patch reworks ebddf1a8d78a ("netfilter: nf_tables: allow to bind table to
net_device").

Note that this adds a dev_name field in the nft_base_chain structure which is
required the netdev notification subscription that follows up in a patch to
handle gone net_devices.

Suggested-by: Patrick McHardy 
Signed-off-by: Pablo Neira Ayuso

netfilter: ipset: Fix coding styles reported by checkpatch.pl

2015-06-14T08:40:18+00:00

Signed-off-by: Jozsef Kadlecsik

Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next

2015-05-31T07:02:30+00:00

Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next, they are:

1) default CONFIG_NETFILTER_INGRESS to y for easier compile-testing of all
   options.

2) Allow to bind a table to net_device. This introduces the internal
   NFT_AF_NEEDS_DEV flag to perform a mandatory check for this binding.
   This is required by the next patch.

3) Add the 'netdev' table family, this new table allows you to create ingress
   filter basechains. This provides access to the existing nf_tables features
   from ingress.

4) Kill unused argument from compat_find_calc_{match,target} in ip_tables
   and ip6_tables, from Florian Westphal.
====================

Signed-off-by: David S. Miller

netfilter: nf_tables: allow to bind table to net_device

2015-05-26T16:41:17+00:00

This patch adds the internal NFT_AF_NEEDS_DEV flag to indicate that you must
attach this table to a net_device.

This change is required by the follow up patch that introduces the new netdev
table.

Signed-off-by: Pablo Neira Ayuso

conntrack: RFC5961 challenge ACK confuse conntrack LAST-ACK transition

2015-05-15T18:50:56+00:00

In compliance with RFC5961, the network stack send challenge ACK in
response to spurious SYN packets, since commit 0c228e833c88 ("tcp:
Restore RFC5961-compliant behavior for SYN packets").

This pose a problem for netfilter conntrack in state LAST_ACK, because
this challenge ACK is (falsely) seen as ACKing last FIN, causing a
false state transition (into TIME_WAIT).

The challenge ACK is hard to distinguish from real last ACK.  Thus,
solution introduce a flag that tracks the potential for seeing a
challenge ACK, in case a SYN packet is let through and current state
is LAST_ACK.

When conntrack transition LAST_ACK to TIME_WAIT happens, this flag is
used for determining if we are expecting a challenge ACK.

Scapy based reproducer script avail here:
 https://github.com/netoptimizer/network-testing/blob/master/scapy/tcp_hacks_3WHS_LAST_ACK.py

Fixes: 0c228e833c88 ("tcp: Restore RFC5961-compliant behavior for SYN packets")
Signed-off-by: Jesper Dangaard Brouer 
Acked-by: Jozsef Kadlecsik 
Signed-off-by: Pablo Neira Ayuso

netfilter: nft_dynset: dynamic stateful expression instantiation

2015-04-13T18:19:55+00:00

Support instantiating stateful expressions based on a template that
are associated with dynamically created set entries. The expressions
are evaluated when adding or updating the set element.

This allows to maintain per flow state using the existing set
infrastructure and expression types, with arbitrary definitions of
a flow.

Usage is currently restricted to anonymous sets, meaning only a single
binding can exist, since the desired semantics of multiple independant
bindings haven't been defined so far.

Examples (userspace syntax is still WIP):

1. Limit the rate of new SSH connections per host, similar to iptables
   hashlimit:

	flow ip saddr timeout 60s \
	limit 10/second \
	accept

2. Account network traffic between each set of /24 networks:

	flow ip saddr & 255.255.255.0 . ip daddr & 255.255.255.0 \
	counter

3. Account traffic to each host per user:

	flow skuid . ip daddr \
	counter

4. Account traffic for each combination of source address and TCP flags:

	flow ip saddr . tcp flags \
	counter

The resulting set content after a Xmas-scan look like this:

{
	192.168.122.1 . fin | psh | urg : counter packets 1001 bytes 40040,
	192.168.122.1 . ack : counter packets 74 bytes 3848,
	192.168.122.1 . psh | ack : counter packets 35 bytes 3144
}

Signed-off-by: Patrick McHardy 
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: add flag to indicate set contains expressions

2015-04-13T18:12:32+00:00

Add a set flag to indicate that the set is used as a state table and
contains expressions for evaluation. This operation is mutually
exclusive with the mapping operation, so sets specifying both are
rejected. The lookup expression also rejects binding to state tables
since it only deals with loopup and map operations.

Signed-off-by: Patrick McHardy 
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: prepare for expressions associated to set elements

2015-04-13T18:12:31+00:00

Preparation to attach expressions to set elements: add a set extension
type to hold an expression and dump the expression information with the
set element.

Signed-off-by: Patrick McHardy 
Signed-off-by: Pablo Neira Ayuso