Define three accessors to get/set dst attached to a skb

struct dst_entry *skb_dst(const struct sk_buff *skb)

void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)

void skb_dst_drop(struct sk_buff *skb)
This one should replace occurrences of :
dst_release(skb->dst)
skb->dst = NULL;

Delete skb->dst field
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/ip6mr.c: In function 'pim6_rcv':
net/ipv6/ip6mr.c:368: error: implicit declaration of function 'csum_ipv6_magic'
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch addresses the IPv6 multicast routing issues described
below.  It was tested with XORP 1.4/1.5 as the IPv6 PIM-SM routing
daemon against FreeBSD peers.

net/ipv6/ip6_input.c:

  - Don't try to forward link-local multicast packets.

  - Don't reset skb2->dev before calling ip6_mr_input() so packets can
    be identified as coming from the PIM register vif properly.

net/ipv6/ip6mr.c:

  - Fix incoming PIM register messages processing:

    * The IPv6 pseudo-header should be included when checksumming PIM
      messages (RFC 4601 section 4.9; RFC 3973 section 4.7.1).

    * Packets decapsulated from PIM register messages should have
      skb->protocol ETH_P_IPV6.

  - Enable/disable IPv6 multicast forwarding on the corresponding
    interface when a routing daemon adds/removes a multicast virtual
    interface.

  - Remove incorrect skb_pull() to fix userspace signaling.

  - Enable/disable global IPv6 multicast forwarding when an IPv6
    multicast routing socket is opened/closed.

net/ipv6/route.c:

  - Don't use strict routing logic for packets decapsulated from PIM
    register messages (similar to disabling rp_filter for the IPv4
    case).
Signed-off-by: NThomas Goff <thomas.goff@boeing.com>
Reviewed-by: NFred Templin <fred.l.templin@boeing.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This last patch makes the appropriate changes to use and propagate the
network namespace where needed in IPv6 multicast forwarding code.

This consists mainly in replacing all the remaining init_net occurences
with current netns pointer retrieved from sockets, net devices or 
mfc6_caches depending on the routines' contexts.

Some routines receive a new 'struct net' parameter to propagate the current
netns:
* ip6mr_get_route
* ip6mr_cache_report
* ip6mr_cache_find
* ip6mr_cache_unresolved
* mif6_add/mif6_delete
* ip6mr_mfc_add/ip6mr_mfc_delete
* ip6mr_reg_vif

All the IPv6 multicast forwarding variables moved to struct netns_ipv6 by
the previous patches are now referenced in the correct namespace.

Changelog:
==========
* Take into account the net associated to mfc6_cache when matching entries in
  mfc_unres_queue list.
* Call mroute_clean_tables() in ip6mr_net_exit() to free memory allocated
  per-namespace.
* Call dev_net_set() in ip6mr_reg_vif() to initialize dev->nd_net 
  correctly.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Declare IPv6 multicast forwarding /proc/net entries per-namespace:
/proc/net/ip6_mr_vif
/proc/net/ip6_mr_cache

Changelog
=========
V2:
* In routine ipmr_mfc_seq_idx(), only match entries belonging to current
  netns in mfc_unres_queue list.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Preliminary work to make IPv6 multicast forwarding netns-aware.

Declare variable 'reg_vif_num' per-namespace, moves into struct netns_ipv6.

At the moment, this variable is only referenced in init_net.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Preliminary work to make IPv6 multicast forwarding netns-aware.

Declare IPv6 multicast forwarding variables 'mroute_do_assert' and
'mroute_do_pim' per-namespace in struct netns_ipv6.

At the moment, these variables are only referenced in init_net.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Preliminary work to make IPv6 multicast forwarding netns-aware.

Declare variable cache_resolve_queue_len per-namespace: moves it into
struct netns_ipv6.

This variable counts the number of unresolved cache entries queued in the
list mfc_unres_queue. This list is kept global to all netns as the number
of entries per namespace is limited to 10 (hardcoded in routine 
ip6mr_cache_unresolved).
Entries belonging to different namespaces in mfc_unres_queue will be
identified by matching the mfc_net member introduced previously in 
struct mfc6_cache.

Keeping this list global to all netns, also allows us to keep a single
timer (ipmr_expire_timer) to handle their expiration.
In some places cache_resolve_queue_len value was tested for arming 
or deleting the timer. These tests were equivalent to testing 
mfc_unres_queue value instead and are replaced in this patch.

At the moment, cache_resolve_queue_len is only referenced in init_net.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Preliminary work to make IPv6 multicast forwarding netns-aware.

Dynamically allocates IPv6 multicast forwarding cache, mfc6_cache_array,
and moves it to struct netns_ipv6. 

At the moment, mfc6_cache_array is only referenced in init_net.

Replace 'ARRAY_SIZE(mfc6_cache_array)' with mfc6_cache_array size: MFC6_LINES.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch stores into struct mfc6_cache the network namespace each
mfc6_cache belongs to. The new member is mfc6_net.

mfc6_net is assigned at cache allocation and doesn't change during
the rest of the cache entry life.

This will help to retrieve the current netns around the IPv6 multicast
forwarding code.

At the moment, all mfc6_cache are allocated in init_net.

Changelog:
==========
* Use write_pnet()/read_pnet() to set and get mfc6_net.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Preliminary work to make IPv6 multicast forwarding netns-aware.

Dynamically allocates interface table vif6_table and moves it to 
struct netns_ipv6, and updates MIF_EXISTS() macro. 

At the moment, vif6_table is only referenced in init_net.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Preliminary work to make IPv6 multicast forwarding netns-aware.

Make IPv6 multicast forwarding mroute6_socket per-namespace,
moves it into struct netns_ipv6.

At the moment, mroute6_socket is only referenced in init_net.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Today, iproute2 fails to show multicast forwarding unresolved cache
entries while scanning /proc/net/ip_mr_cache.

Indeed, it expects to see -1 in 'Iif' column to identify unresolved
entries but the kernel outputs 65535. It's a signed/unsigned issue:

'Iif', the source interface, is retrieved from member mfc_parent in
struct mfc_cache. mfc_parent is a vifi_t: unsigned short, but is
displayed in ipmr_mfc_seq_show() as "%-3d", signed integer.

In unresolevd entries, the 65535 value (0xFFFF) comes from this define:
#define ALL_VIFS    ((vifi_t)(-1))

That may explains why the guy who added support for this in iproute2
thought a -1 should be expected.

I don't know if this must be fixed in kernel or in iproute2. Who is
right? What is the correct API? How was it designed originally?

I let you decide if it should goes in the kernel or be fixed in iproute2.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

/proc/net/ip_mr_cache and /proc/net/ip6_mr_cache displays garbage when
showing unresolved mfc_cache entries.

[root@qemu tests]# cat /proc/net/ip_mr_cache
Group    Origin   Iif     Pkts    Bytes    Wrong Oifs
014C00EF 010014AC 1         10    10050        0  2:1    3:1
024C00EF 010014AC 65535      514        2 -559067475

The first line is correct. It is a resolved cache entry, 10 packets used it...
The second line represents an unresolved entry, and the columns Pkts(4th),
Bytes(5th) and Wrong(6th) just show garbage.

In struct mfc_cache, there's an union to store data for resolved and
unresolved cases. And what ipmr_mfc_seq_show() is printing in these 
columns for the unresolved entries is some bytes from mfc_cache.mfc_un.res.
Bad.
(eg. In our case -559067475 is in fact 0xdead4ead which is the spinlock
magic from mfc_cache.mfc_un.unres.unresolved.lock.magic).

This patch replaces the garbage data written in these columns for the
unresolved entries by '0' (zeros) which is more correct.
This change doesn't break the ABI.

Also, mfc->mfc_un.res.pkt, mfc->mfc_un.res.bytes, mfc->mfc_un.res.wrong_if
are unsigned long.

It applies on top of net-next-2.6.

The patch for net-2.6 is slightly different because of the NIP6_FMT to
%pI6 conversion that was made in the seq_printf.

Changelog:
==========
V2:
* Instead of breaking the ABI by suppressing the columns that have no
  meaning for unresolved entries, fill them with 0 values.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert to new network device ops interface.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In ip6mr.c, /proc entries /proc/net/ip6_mr_cache and /proc/net/ip6_mr_vif
are opened with seq_open_private(), thus seq_release_private() should be 
used to release them.
Should fix a small memory leak.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The order of cleanup operations in the error/exit section of ip6_mr_init()
is completely inversed. It should be the other way around.
Also a del_timer() is missing in the error path.
Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Without CONFIG_NET_NS, namespace is always &init_net.
Compiler will be able to omit namespace comparisons with this patch.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Patrick McHardy pointed it out.
Signed-off-by: NWang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

allmulti might overflow.
Commit: "netdevice: Fix promiscuity and allmulti overflow" in net-next makes
dev_set_promiscuity/allmulti return error number if overflow happened.

Here, we check the positive increment for allmulti to get error return.
Signed-off-by: NWang Chen <wangchen@cn.fujitsu.com>
Acked-by: Patrick McHardy <kaber@trash.net> 
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If do not do it, we will get following issues:
1. Leaving junks after inet6_init failing halfway.
2. Leaving proc and notifier junks after ipv6 modules unloading.
Signed-off-by: NWang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

MRT6_VERSION should be used instead of MRT_VERSION in ip6mr.c.
Signed-off-by: NRami Rosen <ramirose@gmail.com>
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

ptrdiff_t is %t..., not %Z...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Similar to ipmr.

[ Fix build failures -DaveM ]
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

This patches adds a call to increment IPSTATS_MIB_OUTFORWDATAGRAMS
when forwarding the packet in ip6_mr_forward() in the IPv6 multicast
routing module (net/ipv6/ip6mr.c).
Signed-off-by: NRami Rosen <ramirose@gmail.com>
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since NETDEV_REGISTER notifier chain is responsible for creating
inet6_dev{}, we do not need to call ipv6_find_idev() directly here.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- This patch adjusts IPv6 multicast routing module, net/ipv6/ip6mr.c,
to use mroute6 header definitions instead of mroute.
 (MFC6_LINES instead of MFC_LINES, MAXMIFS instead of MAXVIFS, mifi_t
instead of vifi_t.)

- In addition, inclusion of some headers was removed as it is not needed.
Signed-off-by: NRami Rosen <ramirose@gmail.com>
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

| net/ipv6/ipv6_sockglue.c:162:16: warning: symbol 'net' shadows an earlier one
| net/ipv6/ipv6_sockglue.c:111:13: originally declared here
| net/ipv6/ipv6_sockglue.c:175:16: warning: symbol 'net' shadows an earlier one
| net/ipv6/ipv6_sockglue.c:111:13: originally declared here
| net/ipv6/ip6mr.c:1241:10: warning: symbol 'ret' shadows an earlier one
| net/ipv6/ip6mr.c:1163:6: originally declared here
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

This bug resulted in compilation error on 64bit machines.
Pointed out by Rami Rosen <roszenrami@gmail.com>.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

Based on ancient patch by Mickael Hoerdt
<hoerdt@clarinet.u-strasbg.fr>, which is available at
<http://www-r2.u-strasbg.fr/~hoerdt/dev/linux_ipv6_mforwarding/patch-linux-ipv6-mforwarding-0.1a>.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

Based on ancient patch by Mickael Hoerdt
<hoerdt@clarinet.u-strasbg.fr>, which is available at
<http://www-r2.u-strasbg.fr/~hoerdt/dev/linux_ipv6_mforwarding/patch-linux-ipv6-mforwarding-0.1a>.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>