linux-stable.git/net/ipv4/ip_gre.c, branch v3.7

gre: fix sparse warning

2012-10-01T21:35:31+00:00

Use be16 consistently when looking at flags.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller

ipv4: gre: add GRO capability

2012-10-01T21:01:57+00:00

Add GRO capability to IPv4 GRE tunnels, using the gro_cells
infrastructure.

Tested using IPv4 and IPv6 TCP traffic inside this tunnel, and
checking GRO is building large packets.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

tunnel: drop packet if ECN present with not-ECT

2012-09-27T22:12:37+00:00

Linux tunnels were written before RFC6040 and therefore never
implemented the corner case of ECN getting set in the outer header
and the inner header not being ready for it.

Section 4.2.  Default Tunnel Egress Behaviour.
 o If the inner ECN field is Not-ECT, the decapsulator MUST NOT
      propagate any other ECN codepoint onwards.  This is because the
      inner Not-ECT marking is set by transports that rely on dropped
      packets as an indication of congestion and would not understand or
      respond to any other ECN codepoint [RFC4774].  Specifically:

      *  If the inner ECN field is Not-ECT and the outer ECN field is
         CE, the decapsulator MUST drop the packet.

      *  If the inner ECN field is Not-ECT and the outer ECN field is
         Not-ECT, ECT(0), or ECT(1), the decapsulator MUST forward the
         outgoing packet with the ECN field cleared to Not-ECT.

This patch moves the ECN decap logic out of the individual tunnels
into a common place.

It also adds logging to allow detecting broken systems that
set ECN bits incorrectly when tunneling (or an intermediate
router might be changing the header).

Overloads rx_frame_error to keep track of ECN related error.

Thanks to Chris Wright who caught this while reviewing the new VXLAN
tunnel.

This code was tested by injecting faulty logic in other end GRE
to send incorrectly encapsulated packets.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller

gre: remove unnecessary rcu_read_lock/unlock

2012-09-27T22:12:37+00:00

The gre function pointers for receive and error handling are
always called (from gre.c) with rcu_read_lock already held.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller

gre: fix handling of key 0

2012-09-27T22:12:37+00:00

GRE driver incorrectly uses zero as a flag value. Zero is a perfectly
valid value for key, and the tunnel should match packets with no key only
with tunnels created without key, and vice versa.

This is a slightly visible  change since previously it might be possible to
construct a working tunnel that sent key 0 and received only because
of the key wildcard of zero.  I.e the sender sent key of zero, but tunnel
was defined without key.

Note: using gre key 0 requires iproute2 utilities v3.2 or later.
The original utility code was broken as well.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller

gre: add GSO support

2012-09-19T19:40:15+00:00

Add GSO support to GRE tunnels.

Signed-off-by: Eric Dumazet 
Cc: Maciej Żenczykowski 
Signed-off-by: David S. Miller

ipv4: Adjust semantics of rt->rt_gateway.

2012-07-20T20:31:20+00:00

In order to allow prefixed routes, we have to adjust how rt_gateway
is set and interpreted.

The new interpretation is:

1) rt_gateway == 0, destination is on-link, nexthop is iph->daddr

2) rt_gateway != 0, destination requires a nexthop gateway

Abstract the fetching of the proper nexthop value using a new
inline helper, rt_nexthop(), as suggested by Joe Perches.

Signed-off-by: David S. Miller 
Tested-by: Vijay Subramanian

net: Pass optional SKB and SK arguments to dst_ops->{update_pmtu,redirect}()

2012-07-17T10:29:28+00:00

This will be used so that we can compose a full flow key.

Even though we have a route in this context, we need more.  In the
future the routes will be without destination address, source address,
etc. keying.  One ipv4 route will cover entire subnets, etc.

In this environment we have to have a way to possess persistent storage
for redirects and PMTU information.  This persistent storage will exist
in the FIB tables, and that's why we'll need to be able to rebuild a
full lookup flow key here.  Using that flow key will do a fib_lookup()
and create/update the persistent entry.

Signed-off-by: David S. Miller

ipv4: Add redirect support to all protocol icmp error handlers.

2012-07-12T04:27:49+00:00

Signed-off-by: David S. Miller

ipv4: Handle PMTU in all ICMP error handlers.

2012-06-15T05:22:07+00:00

With ip_rt_frag_needed() removed, we have to explicitly update PMTU
information in every ICMP error handler.

Create two helper functions to facilitate this.

1) ipv4_sk_update_pmtu()

   This updates the PMTU when we have a socket context to
   work with.

2) ipv4_update_pmtu()

   Raw version, used when no socket context is available.  For this
   interface, we essentially just pass in explicit arguments for
   the flow identity information we would have extracted from the
   socket.

   And you'll notice that ipv4_sk_update_pmtu() is simply implemented
   in terms of ipv4_update_pmtu()

Note that __ip_route_output_key() is used, rather than something like
ip_route_output_flow() or ip_route_output_key().  This is because we
absolutely do not want to end up with a route that does IPSEC
encapsulation and the like.  Instead, we only want the route that
would get us to the node described by the outermost IP header.

Reported-by: Steffen Klassert 
Signed-off-by: David S. Miller