Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

MFC r229002:
Set svn:executable on dhclient-script

Sponsored by: Yakaz (http://www.yakaz.com)

MFC r228259:
Support domain-search in dhclient(8)

The "domain-search" option (option 119) allows a DHCP server to publish
a list of implicit domain suffixes used during name lookup. This option
is described in RFC 3397.

For instance, if the domain-search option says:
".example.org .example.com"
and one wants to resolve "foobar", the resolver will try:
1. "foobar.example.org"
2. "foobar.example.com"

The file /etc/resolv.conf is updated with a "search" directive if the
DHCP server provides "domain-search".

A regression test suite is included in this patch under
tools/regression/sbin/dhclient.

PR: bin/151940
Sponsored by: Yakaz (http://www.yakaz.com)

MFC r229000:
Invalid Domain Search option isn't considered as a fatal error

In the original Domain Search option patch, an invalid option value
would cause the whole lease to be rejected. However, DHCP servers who
emit such an invalid value are more common than I thought. With this new
patch, just the option is rejected, not the entire lease.

PR: bin/163431
Submitted by: Fabian Keil <fk@fabiankeil.de> (earlier version)
Reviewed by: Fabian Keil <fk@fabiankeil.de>
Sponsored by: Yakaz (http://www.yakaz.com)

MFC r229001:
Adapt testsuite following change in Domain Search error handling

In this testsuite, warning() and error() have the same behaviour.

PR: bin/163431
Sponsored by: Yakaz (http://www.yakaz.com)

Merge r228463, that explicily uses 255.0.0.0 mask for the temporary prefix.
This change isn't actually needed in the stable/9, but let it be here, in
case if anyone tries to run stable/9 world on a head/ kernel.

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Use resolvconf(8) to update /etc/resolv.conf.
If you don't want to use resolvconf(8) to update /etc/resolv.conf,
you can put resolvconf_enable="NO" into /etc/dhclient-enter-hooks.

Use the -n flag to route(8) when calling "route get". Otherwise we hang
for a long time if we get a lease, but DNS isn't working.

MFC after: 1 week

Add a new function is_default_interface() which determines if this
interface is one with the default route (or there isn't one). Use it to
decide if we should adjust the default route and /etc/resolv.conf.

Fix the delete of the default route. The if statement was totally bogus
and the delete only worked due to a typo. [1]

Reported by: Jordan Coleman <jordan at JordanColeman dot com> [1]
MFC after: 1 week

During PREINIT, when giving the interface the address 0.0.0.0, do it as an
alias to avoid distrubing other addresses.

PR: bin/119255
Submitted by: Jaakko Heinonen <jh at saunalahti dot fi>

Use the -n flag on ifconfig so that dhclient does not cause the kernel module
to be reloaded when the interface is torn down.

Reviewed by: brooks
Approved by: re (kensmith)

The minimum size of an RFC3442 destination descriptor is five bytes, so
correct test to -ge 5. Without this change an RFC3442 encoded default
route would be ignored.

Reported by: Cedric Jonas <cedric at decemplex dot net>

Implement RFC3442, the Classless Static Route option.

The original DHCP specification includes a route option but it supports
only class-based routes. RFC3442 adds support for specifying the netmask
width for each static route. A variable length encoding is used to minimize
the size of this option.

PR: bin/99534
Submitted by: Andrey V. Elsukov <bu7cher@yandex.ru>
Reviewed by: brooks

Fix rev 1.12.

/tmp may not be writeable yet when dhclient is first run via
/etc/rc.d/netif so using it may not work. Also, writing to a
predictable file in /tmp as root is a really bad idea since a malicious
user may be able to win a race and insert a symlink which will allow
them to cause any file to be overwritten. To solve these problems,
create the tempory file in /var/run which will exist this early and is
writable only by root.

Security: Local risk if users can cause dhclient to run on demand
(such as by unplugging and replugging the network cable).

Give the TIMEOUT case a chance to work by using -t # instead of the
OpenBSD -w # when invoking ping.

PR: bin/92187
Submitted by: "Shin'ya Kumabuchi" <kumabu at t3 dot rim dot or dot jp>
MFC After: 6 days

Make dhclient-script more agreeable with read-only /etc.

PR: 90518
Submitted by: John E. Hein <jhein@timing.com>
MFC after: 3 days

When we give up on an interface, use the arp(8) command to remove all
entries from the interface rather than using ifconfig's delete command.
This preserves non-dhclient configured addresses (though they are wiped
out when dhclient is restarted).

MFC after: 1 week

Avoid updating resolv.conf when no changes have actually occured.

Submitted by: ume

When we fail to aquire a lease, our lease expires without a sucessful
renewal, or we lose link, be more forceful about clearing interface
state so another interface that connects to the same network has a
chance of working. This doesn't address attemping to connect to both at
once, but appears to allow unplugging from a wired interface and then
inserting a wireless card that associates with an AP bridged to the same
LAN.

The $medium string often contains quoted values with spaces in them (ssids,
for example). Follow the example of the ISC script and wrap ifconfig
calls using $medium in eval "..." so this works.

Reported by: iedowse

Use a more robust, grep-free command to get the interface of the current
default route.

Submitted by: Rostislav Krasny <rosti dot bsd at gmail dot com>

Don't and/remove a route to our assigned IP through 127.0.0.1. It
serves no apparent purpose (we commented this out ages ago in the ISC
scripts) and cases problems with some ADSL setups.

Reported by: Rostislav Krasny <rosti dot bsd at gmail dot com>

s/if_defaulroute/if_defaultroute/

We may now handle route updates better.

Add support for /etc/dhclient-enter-hooks to match /etc/dhclient-exit-hooks.

Add support for /etc/dhclient-exit-hooks file.

Tested by: Max Boyarov <max_b at tut dot by>

FreeBSDize the dhclient-script.

Submitted by: sam

This commit was generated by cvs2svn to compensate for changes in r147072,
which included commits to RCS files with non-trunk default branches.

Import the OpenBSD dhclient as shipped with OpenBSD-3.7 (the tag
OPENBSD_3_7).