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#
# For a description of the syntax of this configuration file,
# see scripts/kbuild/config-language.txt.
#
INSERT
config UDHCPD
bool "udhcp server (udhcpd)"
default y
select PLATFORM_LINUX
help
udhcpd is a DHCP server geared primarily toward embedded systems,
while striving to be fully functional and RFC compliant.
config DHCPRELAY
bool "dhcprelay"
default y
depends on UDHCPD
help
dhcprelay listens for dhcp requests on one or more interfaces
and forwards these requests to a different interface or dhcp
server.
config DUMPLEASES
bool "Lease display utility (dumpleases)"
default y
depends on UDHCPD
help
dumpleases displays the leases written out by the udhcpd server.
Lease times are stored in the file by time remaining in lease, or
by the absolute time that it expires in seconds from epoch.
config FEATURE_UDHCPD_WRITE_LEASES_EARLY
bool "Rewrite the lease file at every new acknowledge"
default y
depends on UDHCPD
help
If selected, udhcpd will write a new file with leases every
time a new lease has been accepted, thus eliminating the need
to send SIGUSR1 for the initial writing or updating. Any timed
rewriting remains undisturbed.
config FEATURE_UDHCPD_BASE_IP_ON_MAC
bool "Select IP address based on client MAC"
default n
depends on UDHCPD
help
If selected, udhcpd will base its selection of IP address to offer
on the client's hardware address. Otherwise udhcpd uses the next
consecutive free address.
This reduces the frequency of IP address changes for clients
which let their lease expire, and makes consecutive DHCPOFFERS
for the same client to (almost always) contain the same
IP address.
config DHCPD_LEASES_FILE
string "Absolute path to lease file"
default "/var/lib/misc/udhcpd.leases"
depends on UDHCPD
help
udhcpd stores addresses in a lease file. This is the absolute path
of the file. Normally it is safe to leave it untouched.
config UDHCPC
bool "udhcp client (udhcpc)"
default y
select PLATFORM_LINUX
help
udhcpc is a DHCP client geared primarily toward embedded systems,
while striving to be fully functional and RFC compliant.
The udhcp client negotiates a lease with the DHCP server and
runs a script when a lease is obtained or lost.
config FEATURE_UDHCPC_ARPING
bool "Verify that the offered address is free, using ARP ping"
default y
depends on UDHCPC
help
If selected, udhcpc will send ARP probes and make sure
the offered address is really not in use by anyone. The client
will DHCPDECLINE the offer if the address is in use,
and restart the discover process.
config FEATURE_UDHCPC_SANITIZEOPT
bool "Do not pass malformed host and domain names"
default y
depends on UDHCPC
help
If selected, udhcpc will check some options (such as option 12 -
hostname) and if they don't look like valid hostnames
(for example, if they start with dash or contain spaces),
they will be replaced with string "bad" when exporting
to the environment.
config FEATURE_UDHCP_PORT
bool "Enable '-P port' option for udhcpd and udhcpc"
default n
depends on UDHCPD || UDHCPC
help
At the cost of ~300 bytes, enables -P port option.
This feature is typically not needed.
config UDHCP_DEBUG
int "Maximum verbosity level for udhcp applets (0..9)"
default 9
range 0 9
depends on UDHCPD || UDHCPC || DHCPRELAY
help
Verbosity can be increased with multiple -v options.
This option controls how high it can be cranked up.
Bigger values result in bigger code. Levels above 1
are very verbose and useful for debugging only.
config FEATURE_UDHCP_RFC3397
bool "Support for RFC3397 domain search (experimental)"
default y
depends on UDHCPD || UDHCPC
help
If selected, both client and server will support passing of domain
search lists via option 119, specified in RFC 3397,
and SIP servers option 120, specified in RFC 3361.
config FEATURE_UDHCP_8021Q
bool "Support for 802.1Q VLAN parameters"
default y
depends on UDHCPD || UDHCPC
help
If selected, both client and server will support passing of VLAN
ID and priority via options 132 and 133 as per 802.1Q.
config UDHCPC_DEFAULT_SCRIPT
string "Absolute path to config script"
default "/usr/share/udhcpc/default.script"
depends on UDHCPC
help
This script is called after udhcpc receives an answer. See
examples/udhcp for a working example. Normally it is safe
to leave this untouched.
config UDHCPC_SLACK_FOR_BUGGY_SERVERS
int "DHCP options slack buffer size"
default 80
range 0 924
depends on UDHCPD || UDHCPC
help
Some buggy DHCP servers send DHCP offer packets with option
field larger than we expect (which might also be considered a
buffer overflow attempt). These packets are normally discarded.
If circumstances beyond your control force you to support such
servers, this may help. The upper limit (924) makes dhcpc accept
even 1500 byte packets (maximum-sized ethernet packets).
This option does not make dhcp[cd] emit non-standard
sized packets.
Known buggy DHCP servers:
3Com OfficeConnect Remote 812 ADSL Router:
seems to confuse maximum allowed UDP packet size with
maximum size of entire IP packet, and sends packets which are
28 bytes too large.
Seednet (ISP) VDSL: sends packets 2 bytes too large.
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