2 # For a description of the syntax of this configuration file,
3 # see scripts/kbuild/config-language.txt.
9 bool "udhcpd (DHCP server)"
13 udhcpd is a DHCP server geared primarily toward embedded systems,
14 while striving to be fully functional and RFC compliant.
16 config FEATURE_UDHCPD_WRITE_LEASES_EARLY
17 bool "Rewrite the lease file at every new acknowledge"
21 If selected, udhcpd will write a new file with leases every
22 time a new lease has been accepted, thus eliminating the need
23 to send SIGUSR1 for the initial writing or updating. Any timed
24 rewriting remains undisturbed.
26 config FEATURE_UDHCPD_BASE_IP_ON_MAC
27 bool "Select IP address based on client MAC"
31 If selected, udhcpd will base its selection of IP address to offer
32 on the client's hardware address. Otherwise udhcpd uses the next
33 consecutive free address.
35 This reduces the frequency of IP address changes for clients
36 which let their lease expire, and makes consecutive DHCPOFFERS
37 for the same client to (almost always) contain the same
40 config DHCPD_LEASES_FILE
41 string "Absolute path to lease file"
42 default "/var/lib/misc/udhcpd.leases"
45 udhcpd stores addresses in a lease file. This is the absolute path
46 of the file. Normally it is safe to leave it untouched.
52 dumpleases displays the leases written out by the udhcpd.
53 Lease times are stored in the file by time remaining in lease, or
54 by the absolute time that it expires in seconds from epoch.
60 dhcprelay listens for dhcp requests on one or more interfaces
61 and forwards these requests to a different interface or dhcp
65 bool "udhcpc (DHCP client)"
69 udhcpc is a DHCP client geared primarily toward embedded systems,
70 while striving to be fully functional and RFC compliant.
72 The udhcp client negotiates a lease with the DHCP server and
73 runs a script when a lease is obtained or lost.
75 config FEATURE_UDHCPC_ARPING
76 bool "Verify that the offered address is free, using ARP ping"
80 If selected, udhcpc will send ARP probes and make sure
81 the offered address is really not in use by anyone. The client
82 will DHCPDECLINE the offer if the address is in use,
83 and restart the discover process.
85 config FEATURE_UDHCPC_SANITIZEOPT
86 bool "Do not pass malformed host and domain names"
90 If selected, udhcpc will check some options (such as option 12 -
91 hostname) and if they don't look like valid hostnames
92 (for example, if they start with dash or contain spaces),
93 they will be replaced with string "bad" when exporting
96 config UDHCPC_DEFAULT_SCRIPT
97 string "Absolute path to config script"
98 default "/usr/share/udhcpc/default.script"
101 This script is called after udhcpc receives an answer. See
102 examples/udhcp for a working example. Normally it is safe
103 to leave this untouched.
105 config FEATURE_UDHCP_PORT
106 bool "Enable '-P port' option for udhcpd and udhcpc"
108 depends on UDHCPD || UDHCPC
110 At the cost of ~300 bytes, enables -P port option.
111 This feature is typically not needed.
114 int "Maximum verbosity level for udhcp applets (0..9)"
117 depends on UDHCPD || UDHCPC || DHCPRELAY
119 Verbosity can be increased with multiple -v options.
120 This option controls how high it can be cranked up.
122 Bigger values result in bigger code. Levels above 1
123 are very verbose and useful for debugging only.
125 config FEATURE_UDHCP_RFC3397
126 bool "Support RFC3397 domain search (experimental)"
128 depends on UDHCPD || UDHCPC
130 If selected, both client and server will support passing of domain
131 search lists via option 119, specified in RFC 3397,
132 and SIP servers option 120, specified in RFC 3361.
134 config FEATURE_UDHCP_8021Q
135 bool "Support 802.1Q VLAN parameters"
137 depends on UDHCPD || UDHCPC
139 If selected, both client and server will support passing of VLAN
140 ID and priority via options 132 and 133 as per 802.1Q.
142 config UDHCPC_SLACK_FOR_BUGGY_SERVERS
143 int "DHCP options slack buffer size"
146 depends on UDHCPD || UDHCPC
148 Some buggy DHCP servers send DHCP offer packets with option
149 field larger than we expect (which might also be considered a
150 buffer overflow attempt). These packets are normally discarded.
151 If circumstances beyond your control force you to support such
152 servers, this may help. The upper limit (924) makes dhcpc accept
153 even 1500 byte packets (maximum-sized ethernet packets).
155 This option does not make dhcp[cd] emit non-standard
158 Known buggy DHCP servers:
159 3Com OfficeConnect Remote 812 ADSL Router:
160 seems to confuse maximum allowed UDP packet size with
161 maximum size of entire IP packet, and sends packets which are
163 Seednet (ISP) VDSL: sends packets 2 bytes too large.