Commit Graph

108 Commits

Author SHA1 Message Date
brian
4a62a5c343 Document dhclient-enter-hooks and dhclient-exit-hooks and mention
how to configure dhclient to clear the interface of IP numbers prior
to configuring it.

PR:		149351
MFC after:	2 weeks
2010-09-06 09:59:10 +00:00
brian
66f8be2c3a When dhclient obtains a lease, it runs dhclient-script and expects
it to configure the interface.  When the script is complete, dhclient
monitors the routing socket and will terminate if its address is
deleted or if its interface is removed or brought down.

Because the routing socket is already open when dhclient-script is
run, dhclient ignores address deletions for 10 seconds after the
script was run.

If the address that will be obtained is already configured on the
interface before dhclient starts, and if dhclient-script takes more
than 10 seconds (perhaps due to dhclient-*-hooks latencies), on script
completion, dhclient will immediately and silently exit when it sees
the RTM_DELADDR routing message resulting from the script reassigning
the address to the interface.

This change logs dhclient's reason for exiting and also changes the
10 second timeout to be effective from completion of dhclient-script
rather than from when it was started.

We now ignore RTM_DELADDR and RTM_NEWADDR messages when the message
contains no interface address (which should not happen) rather than
exiting.

Not reviewed by:	brooks (timeout)
MFC after:		3 weeks
2010-07-07 06:06:54 +00:00
philip
a72663b23b Make dhclient use bootpc (68) as the source port for unicast DHCPREQUEST
packets instead of allowing the protocol stack to pick a random source port.

This fixes the behaviour where dhclient would never transition from RENEWING
to BOUND without going through REBINDING in networks which are paranoid about
DHCP spoofing, such as most mainstream cable-broadband ISP networks.

Reviewed by:	brooks
Obtained from:	OpenBSD (partly - I'm not convinced their solution can work)
MFC after:	1 week (pending re approval)
2009-10-21 23:50:35 +00:00
ru
763b9ae1f8 Switch the default WARNS level for sbin/ to 6.
Submitted by:	Ulrich Spörlein
2009-10-19 16:00:24 +00:00
sam
681dc8671b Fix the logic to count the number of "live interfaces". With this change
dhclient now terminates when the underlying ifnet is destroyed (e.g.
on card eject).

Reviewed by:	brooks
Approved by:	re (kib)
2009-07-21 15:06:10 +00:00
brian
b5a9006bf0 Fix an off by one error when we limit append/prepend text sizes based on our
internal buffer sizes.

When we 'append', assume we're appending to text.  Some MS dhcp servers will
give us a string with the length including the trailing NUL.  when we 'append
domain-name', we get something like "search x.y\000 z" in resolv.conf :(

MFC after:	1 week
Security:	A buffer overflow (by one NUL byte) was possible.
2009-06-08 21:42:30 +00:00
brooks
a9d132d46a Support the remaining options listed in dhcp-options(5) and RFC 2132.
PR:		bin/127076
Submitted by:	jkim
MFC after:	1 week
2008-10-17 13:28:53 +00:00
ed
0637892261 Run the privileged dhclient process in its own session.
In the MPSAFE TTY branch, I noticed PTY's to be leaked, because
dhclient's privileged process was run inside the session of, say, the
login shell. Make sure we call setsid() here.

Approved by:	philip (mentor), brooks
2008-06-30 20:23:49 +00:00
brooks
675039c544 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
2008-06-09 20:03:35 +00:00
brooks
c390aa9572 When sending packets directly to the DHCP server, use a socket and send
directly rather than bogusly sending it out as a link layer broadcast
(which fails to be received on some networks).

PR:		bin/96018
MFC after:	2 weeks
2008-04-15 22:48:56 +00:00
brooks
59722cbdc9 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
2008-03-30 02:42:39 +00:00
sam
92ad9709eb Defer state change on disassociate to avoid unnecessarily dropping the
lease: track the current bssid and if it changes (as reported in an
assoc/reassoc) event only then kick the state machine.  This gives us
immediate response when roaming but otherwise causes us to fallback on
the normal state machine.

Reviewed by:	brooks, jhb
MFC after:	3 weeks
2008-03-22 16:24:02 +00:00
sam
ba857311dd correct syslog mask so LOG_DEBUG msgs are not lost
MFC after:	2 weeks
2008-03-22 16:18:07 +00:00
brooks
e3cf5b7e24 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>
2008-01-21 23:54:57 +00:00
jkim
bc9e265c9f Teach dhclient(8) about net80211 link (association) status.
Reviewed by:	brooks
MFC after:	3 days
2007-12-05 17:13:45 +00:00
gabor
115dee56e9 - Remove references to unexisting man pages
PR:		docs/116099
Submitted by:	Ben Kaduk <minimarmot@gmail.com>
Approved by:	re (bmah)
MFC after:	3 days
2007-09-20 10:46:25 +00:00
thompsa
a5a2c7551b 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)
2007-07-03 17:49:32 +00:00
emaste
761c2b3c1d 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>
2007-04-13 15:07:10 +00:00
emaste
4d18a6391e 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
2007-02-09 17:50:26 +00:00
emaste
d6a37ef695 Add a $FreeBSD$ tag missing after the original import. Note that this
file isn't actually installed; the one in src/etc is.
2007-02-09 16:28:25 +00:00
brooks
68bfc5b678 Actually implement rev 1.12 for host names and NIS domain names. We
were removing the invalid option, but still rejecting the lease.

Reported by:	Yoshihiko Sarumaru <mistral at imasy dot or dot jp>
2007-01-29 15:55:13 +00:00
brooks
a0d200f631 It is possible for bpf to return a length such that:
length != BPF_WORDALIGN(length)

This meeans that it is possible for this to be true:

	interface->rbuf_offset > interface->rbuf_len

Handle this case in the test for running out of packets.  While
OpenBSD's solution of setting interface->rbuf_len to
BPF_WORDALIGN(length) is safe due to the size of the buffer, I think
this solution results in less hidden assumptions.

This should fix the problem of dhclient running away and consuming 100%
CPU.

PR:		bin/102226
Submitted by:	Joost Bekkers <joost at jodocus.org>
MFC after:	3 days
2006-09-26 01:02:02 +00:00
brian
1e80c6d4b6 Revert the addition of -p. It's flawed in that dhclient should not run
on an interface without carrier.  devd should be used instead to handle
link up/down events.

Put on the right path by:	brooks, sam
2006-08-21 16:31:31 +00:00
brian
768073acd7 Bump the document date. s/dhclient/.Nm/
Suggested by: ru
2006-08-17 20:11:21 +00:00
brian
68f1f47647 Correct usage() 2006-08-17 17:27:42 +00:00
brian
a3922ffaf6 Add a -p switch to dhclient. The switch tells dhclient to persist
despite the interface link status.

Add dhclient_flags_iface and background_dhclient_iface rc.conf options.
(where iface is a specific interface).  These can be used to give
interface specific flags to dhclient.

Reviewed by:	brooks@
2006-08-17 17:12:27 +00:00
jkim
47919b584b Send client identifier unconditionally. My ancient D-Link router response
with NACK if I don't set it.  Setting 'option dhcp-client-identifier' is
alternative but it is inconvenient because I have to keep the list of
all MAC addresses.  As bin/94743 pointed out, it is always sent from
Windows clients and I found Mac OS X does the same.

OK'd by:	brooks
2006-07-03 22:05:38 +00:00
imp
9f41dd8997 Remove 'n' from the getopt string. There's no -n option that is
parsed, so it winds up at usage anyway.

Add 'b' to the usage summary.  Noticed by Ben Mesander.
2006-05-23 16:57:47 +00:00
brooks
74f46cfedd Be more like Windows and Linux and send our hostname in the host-name
option if none is given in the config file.  Also add #ifdefd out
support for sending a client ID based on our MAC address.

PR:		bin/94743, bin/76401
Submitted by:	Frank Behrens <frank at pinky dot sax dot de>
X-MFC after:	6.1-RELEASE
2006-05-07 23:31:10 +00:00
jcamou
d3a1c26f55 Correct RFC for NTP.
PR:		docs/92629
Submitted by:	Daniel Gerzo <danger@rulez.sk>
Noticed by:	Michal F. Hanula <f@7f000001.org>
Approved by:	trhodes (mentor)
2006-02-06 19:22:34 +00:00
brooks
7ba1cf1d54 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).
2006-01-26 21:05:39 +00:00
brooks
003b8b204f 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
2006-01-24 06:11:55 +00:00
wes
e00a5cdab0 Make dhclient-script more agreeable with read-only /etc.
PR:		90518
Submitted by:	John E. Hein <jhein@timing.com>
MFC after:	3 days
2006-01-23 05:42:59 +00:00
brooks
058bf820d7 Mention the -b flag in the SYNOPSIS.
MFC after:	1 week
2006-01-10 05:44:11 +00:00
brooks
782a252f49 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
2006-01-10 05:33:33 +00:00
brooks
1c7bd4aed4 Allow users to add aliases to the interface.
PR:		bin/87465 (different solution used)
MFC after:	1 week
2006-01-10 04:53:20 +00:00
brooks
3354610e7d When we get a bogus hostname in an option, drop the option rather than
refusing the lease.  This allow obtaining leases on misadministered
networks that use host names with underscores in them.

MFC After: 3 days
2005-12-10 03:46:14 +00:00
brooks
29fd49dcdf Avoid updating resolv.conf when no changes have actually occured.
Submitted by:	ume
2005-09-08 22:49:17 +00:00
brooks
4384a74406 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.
2005-09-08 22:15:19 +00:00
brooks
d8570c33a3 When we supersed the subnet-mask, write the forced value to the lease
file.  This is what the ISC client does.

Submitted by:	Rostislav Krasny <rosti dot bsd at gmail dot com>
2005-09-02 17:35:35 +00:00
brooks
40d25976f1 Introduce a new helper function check_search() derived for res_hnok to
check the domain-name parameter according to the rules for "search"
strings as documented in resolv.conf(5).  Specifically, the string must
be no more than 256 bytes long and contain no more than six valid domain
names separated by white space.

The previous unchecked values could result in a mangled resolv.conf
file which could effectively deny access to local sites.  This is not
a security issue as rogue dhcp servers could already do this without
sending invalid strings.

Reviewed by:	cperciva
MFC After:	3 days
2005-08-30 18:20:46 +00:00
brooks
b9888c7410 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
2005-08-26 20:31:04 +00:00
brooks
2263ae4a8d In read_string(), when the last character was a backslash, unincrement
the output index instead of keeping what ever trash was in the buffer.

Reported by:	iedowse
2005-08-26 01:25:59 +00:00
brooks
8f09bbbbfb 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>
2005-08-26 01:07:51 +00:00
brooks
c56a18dd49 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>
2005-08-26 01:02:38 +00:00
brooks
09bbc99b5a MFOpenBSD rev 1.9: fix a buffer overflow when processing config file
lines that are exactly 81 characters in length.

Obtained from:	OpenBSD
MFC After:	3 days
2005-08-24 00:05:04 +00:00
brooks
b9c30d0c57 Add __FBSDID to all .c files in dhclient to aid in determining file
versions when dealing with user problems.
2005-08-23 23:59:55 +00:00
csjp
d3eff5cec1 FreeBSD unconditionally supports write filters now. 2005-08-23 01:35:38 +00:00
brooks
f45086ab80 Further fix receive_packet() by using BPF_WORDALIGN to insure the offset
is properly aligned when we move to the next packet.

Obtained from:	ISC dhclient via krw at OpenBSD
2005-07-28 15:30:19 +00:00
brooks
80e3e886b5 Don't reject packets with server names containing characters that are
not allowed in domain names.  RFC 2132 does not list valid or invalid
characters and the ISC client accepts anything here.

Reported by:	ps
2005-07-28 00:24:39 +00:00