2 # For a description of the syntax of this configuration file,
3 # see scripts/kbuild/config-language.txt.
9 bool "udhcp server (udhcpd)"
13 udhcpd is a DHCP server geared primarily toward embedded systems,
14 while striving to be fully functional and RFC compliant.
21 dhcprelay listens for dhcp requests on one or more interfaces
22 and forwards these requests to a different interface or dhcp
26 bool "Lease display utility (dumpleases)"
30 dumpleases displays the leases written out by the udhcpd server.
31 Lease times are stored in the file by time remaining in lease, or
32 by the absolute time that it expires in seconds from epoch.
34 config FEATURE_UDHCPD_WRITE_LEASES_EARLY
35 bool "Rewrite the lease file at every new acknowledge"
39 If selected, udhcpd will write a new file with leases every
40 time a new lease has been accepted, thus eliminating the need
41 to send SIGUSR1 for the initial writing or updating. Any timed
42 rewriting remains undisturbed.
44 config FEATURE_UDHCPD_BASE_IP_ON_MAC
45 bool "Select IP address based on client MAC"
49 If selected, udhcpd will base its selection of IP address to offer
50 on the client's hardware address. Otherwise udhcpd uses the next
51 consecutive free address.
53 This reduces the frequency of IP address changes for clients
54 which let their lease expire, and makes consecutive DHCPOFFERS
55 for the same client to (almost always) contain the same
58 config DHCPD_LEASES_FILE
59 string "Absolute path to lease file"
60 default "/var/lib/misc/udhcpd.leases"
63 udhcpd stores addresses in a lease file. This is the absolute path
64 of the file. Normally it is safe to leave it untouched.
67 bool "udhcp client (udhcpc)"
71 udhcpc is a DHCP client geared primarily toward embedded systems,
72 while striving to be fully functional and RFC compliant.
74 The udhcp client negotiates a lease with the DHCP server and
75 runs a script when a lease is obtained or lost.
77 config FEATURE_UDHCPC_ARPING
78 bool "Verify that the offered address is free, using ARP ping"
82 If selected, udhcpc will send ARP probes and make sure
83 the offered address is really not in use by anyone. The client
84 will DHCPDECLINE the offer if the address is in use,
85 and restart the discover process.
87 config FEATURE_UDHCPC_SANITIZEOPT
88 bool "Do not pass malformed host and domain names"
92 If selected, udhcpc will check some options (such as option 12 -
93 hostname) and if they don't look like valid hostnames
94 (for example, if they start with dash or contain spaces),
95 they will be replaced with string "bad" when exporting
98 config FEATURE_UDHCP_PORT
99 bool "Enable '-P port' option for udhcpd and udhcpc"
101 depends on UDHCPD || UDHCPC
103 At the cost of ~300 bytes, enables -P port option.
104 This feature is typically not needed.
107 int "Maximum verbosity level for udhcp applets (0..9)"
110 depends on UDHCPD || UDHCPC || DHCPRELAY
112 Verbosity can be increased with multiple -v options.
113 This option controls how high it can be cranked up.
115 Bigger values result in bigger code. Levels above 1
116 are very verbose and useful for debugging only.
118 config FEATURE_UDHCP_RFC3397
119 bool "Support for RFC3397 domain search (experimental)"
121 depends on UDHCPD || UDHCPC
123 If selected, both client and server will support passing of domain
124 search lists via option 119, specified in RFC 3397,
125 and SIP servers option 120, specified in RFC 3361.
127 config FEATURE_UDHCP_8021Q
128 bool "Support for 802.1Q VLAN parameters"
130 depends on UDHCPD || UDHCPC
132 If selected, both client and server will support passing of VLAN
133 ID and priority via options 132 and 133 as per 802.1Q.
135 config UDHCPC_DEFAULT_SCRIPT
136 string "Absolute path to config script"
137 default "/usr/share/udhcpc/default.script"
140 This script is called after udhcpc receives an answer. See
141 examples/udhcp for a working example. Normally it is safe
142 to leave this untouched.
144 config UDHCPC_SLACK_FOR_BUGGY_SERVERS
145 int "DHCP options slack buffer size"
148 depends on UDHCPD || UDHCPC
150 Some buggy DHCP servers send DHCP offer packets with option
151 field larger than we expect (which might also be considered a
152 buffer overflow attempt). These packets are normally discarded.
153 If circumstances beyond your control force you to support such
154 servers, this may help. The upper limit (924) makes dhcpc accept
155 even 1500 byte packets (maximum-sized ethernet packets).
157 This option does not make dhcp[cd] emit non-standard
160 Known buggy DHCP servers:
161 3Com OfficeConnect Remote 812 ADSL Router:
162 seems to confuse maximum allowed UDP packet size with
163 maximum size of entire IP packet, and sends packets which are
165 Seednet (ISP) VDSL: sends packets 2 bytes too large.