[RFC PATCH 0/2] l2tp: Introduce L2TPv3 IP encapsulation for IPv6

The following patch series adds support for L2TPv3 IP encapsulation
over IPv6. Support for L2TPv3 IP encap over IPv4 is already present in
the kernel (l2tp_ip). The new code is derived from l2tp_ip and
ipv6/raw. I'm posting as an RFC to get feedback on the approach being
used, because the implementation uses several ipv6 functions which are
not currently exported.

A patch series adding IPv6 support for L2TPv2 and L2TPv3 UDP
encapsulation is being worked on by Ben LaHaise and is independent of
these changes.

James Chapman (2):
  ipv6: Export ipv6 functions for use by other protocols
  l2tp: Introduce L2TPv3 IP encapsulation support for IPv6

 include/linux/l2tp.h     |   17 +
 net/ipv6/datagram.c      |    4 +
 net/ipv6/exthdrs.c       |    1 +
 net/ipv6/ip6_flowlabel.c |    1 +
 net/ipv6/ip6_output.c    |    3 +
 net/l2tp/Makefile        |    1 +
 net/l2tp/l2tp_ip6.c      |  808 ++++++++++++++++++++++++++++++++++++++++++++++
 7 files changed, 835 insertions(+), 0 deletions(-)
 create mode 100644 net/l2tp/l2tp_ip6.c