net: ipv6: Add IPv6 support to the ping socket.

[backport of net-next 6d0bfe22611602f36617bc7aa2ffa1bbb2f54c67]

This adds the ability to send ICMPv6 echo requests without a
raw socket. The equivalent ability for ICMPv4 was added in
2011.

Instead of having separate code paths for IPv4 and IPv6, make
most of the code in net/ipv4/ping.c dual-stack and only add a
few IPv6-specific bits (like the protocol definition) to a new
net/ipv6/ping.c. Hopefully this will reduce divergence and/or
duplication of bugs in the future.

Caveats:

- Setting options via ancillary data (e.g., using IPV6_PKTINFO
  to specify the outgoing interface) is not yet supported.
- There are no separate security settings for IPv4 and IPv6;
  everything is controlled by /proc/net/ipv4/ping_group_range.
- The proc interface does not yet display IPv6 ping sockets
  properly.

Tested with a patched copy of ping6 and using raw socket calls.
Compiles and works with all of CONFIG_IPV6={n,m,y}.

Bug 1412141

Change-Id: I0081b4654dd54b12c8f233e00e18943582aa2142
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[lorenzo@google.com: backported to 3.4]
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
(cherry picked from commit 1f0675844e3b63a765e5bd32bc5af051ccd951c0)
Reviewed-on: http://git-master/r/336269
Reviewed-by: Mrutyunjay Sawant <msawant@nvidia.com>
Tested-by: Mrutyunjay Sawant <msawant@nvidia.com>

Conflicts:
	include/net/ipv6.h
	net/ipv4/af_inet.c
	net/ipv4/icmp.c
	net/ipv4/ping.c
	net/ipv6/Makefile
	net/ipv6/af_inet6.c
	net/ipv6/icmp.c
Change-Id: I6300756942bcf23f4745400c53fdb33301e9815f
Reviewed-on: http://git-master/r/337764
Reviewed-by: Om Prakash Singh <omp@nvidia.com>
Tested-by: Om Prakash Singh <omp@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Bitan Biswas <bbiswas@nvidia.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/net/transp_v6.h b/include/net/transp_v6.h
index 938b7fd11204..eb40e71ff2ee 100644
--- a/include/net/transp_v6.h
+++ b/include/net/transp_v6.h
@@ -11,6 +11,7 @@ extern struct proto rawv6_prot;
 extern struct proto udpv6_prot;
 extern struct proto udplitev6_prot;
 extern struct proto tcpv6_prot;
+extern struct proto pingv6_prot;
 
 struct flowi6;
 
@@ -21,6 +22,8 @@ extern int				ipv6_frag_init(void);
 extern void				ipv6_frag_exit(void);
 
 /* transport protocols */
+extern int				pingv6_init(void);
+extern void				pingv6_exit(void);
 extern int				rawv6_init(void);
 extern void				rawv6_exit(void);
 extern int				udpv6_init(void);