Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Remove __P.

Submitted by: kevlo
Reviewed by: md5(1)
MFC after: 2 months

Clean up VCS Ids.

/* -> /*- for license, minor formatting changes, separate for KAME

- fix typo in comments.
- style.
- NULL is not 0.
- some variables were renamed.
- nuke unused logic.
(there is no functional change.)

Obtained from: KAME

last arg of in6?_gif_output() is not used any more.

Obtained from: KAME
MFC after: 3 weeks

- after gif_set_tunnel(), psrc/pdst may be null. set IFF_RUNNING accordingly.
- set IFF_UP on SIOCSIFADDR. be consistent with others.
- set if_addrlen explicitly (just in case)
- multi destination mode is long gone.
- missing break statement
- add gif_set_tunnel(), so that we can set tunnel address from within the
kernel at ease.
- encap_attach/detach dynamically on ioctls
- move encap_attach() to dedicated function in in*_gif.c

Obtained from: KAME
MFC after: 3 weeks

sync with kame tree as of july00. tons of bug fixes/improvements.

API changes:
- additional IPv6 ioctls
- IPsec PF_KEY API was changed, it is mandatory to upgrade setkey(8).
(also syntax change)

add forward declarations, and small cosmetic changes.

Submitted by: bde

udp IPv6 support, IPv6/IPv4 tunneling support in kernel,
packet divert at kernel for IPv6/IPv4 translater daemon

This includes queue related patch submitted by jburkhol@home.com.

Submitted by: queue related patch from jburkhol@home.com
Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project