README

   1 odhcpd - Embedded DHCP/DHCPv6/RA Server & Relay
   2
   3 ** Abstract **
   4
   5 odhcpd is a daemon for serving and relaying IP management protocols to
   6 configure clients and downstream routers. It tries to follow the RFC 6204
   7 requirements for IPv6 home routers.
   8
   9 odhcpd provides server services for DHCP, RA, stateless and stateful DHCPv6,
  10 prefix delegation and can be used to relay RA, DHCPv6 and NDP between routed
  11 (non-bridged) interfaces in case no delegated prefixes are available.
  12
  13
  14 ** Features **
  15
  16 1. Router Discovery support (solicitations and advertisements) with 2 modes
  17    server:      RD server for slave interfaces
  18    a) automatic detection of prefixes, delegated prefix and default routes, MTU
  19    b) automatic reannouncement when changes to prefixes or routes occur
  20
  21    relay:       RD relay between master and slave interfaces
  22    a) support for rewriting announced DNS-server addresses in relay mode
  23
  24 2. DHCPv6-support with 2 modes of operation
  25    server: stateless, stateful and PD-server mode
  26    a) stateless and stateful address assignment
  27    b) prefix delegation support
  28    c) dynamic reconfiguration in case prefixes change
  29    d) hostname detection and hosts-file creation
  30
  31    relay:       mostly standards-compliant DHCPv6-relay
  32    a) support for rewriting announced DNS-server addresses
  33
  34 3. DHCPv4-support
  35    server: stateless and stateful mode
  36
  37 4. Proxy for Neighbor Discovery messages (solicitations and advertisements)
  38    a) support for auto-learning routes to the local routing table
  39    b) support for marking interfaces "external" not proxying NDP for them
  40       and only serving NDP for DAD and for traffic to the router itself
  41       [Warning: you should provide additional firewall rules for security]
  42
  43
  44 ** Compiling **
  45
  46 odhcpd uses cmake:
  47 * To prepare a Makefile use:  "cmake ."
  48 * To build / install use: "make" / "make install" afterwards.
  49 * To build DEB or RPM packages use: "make package" afterwards.
  50
  51
  52 ** Configuration **
  53
  54 odhcpd uses a UCI configuration file in /etc/config/dhcp for configuration
  55 and may also receive information from ubus
  56
  57
  58 Section of type odhcpd
  59
  60 Option          Type    Default                 Description
  61 legacy          bool    0                       Enable DHCPv4 if start but
  62                                                 no dhcpv4 option set
  63 leasefile       string                          DHCP/v6 lease/hostfile
  64 leasetrigger    string                          Lease trigger script
  65 loglevel        integer 6                       Syslog level priority (0-7)
  66
  67
  68 Sections of type dhcp (configure DHCP / DHCPv6 / RA / NDP service)
  69
  70 Option          Type    Default                 Description
  71 interface       string  <name of UCI section>   logical OpenWrt interface
  72 ifname          string  <resolved from logical> physical network interface
  73 networkid       string  same as ifname          compat. alias for ifname
  74 ignore          bool    0                       do not serve this interface
  75                                                 unless overridden by ra, ndp,
  76                                                 dhcpv4 or dhcpv6 options
  77 master          bool    0                       is a master interface
  78                                                 for relaying
  79
  80 ra              string  disabled                Router Advert service
  81                 [disabled|server|relay|hybrid]
  82 dhcpv6          string  disabled                DHCPv6 service
  83                 [disabled|server|relay|hybrid]
  84 dhcpv4          string  disabled                DHCPv4 service
  85                 [disabled|server]
  86 ndp             string  disabled                Neighbor Discovery Proxy
  87                 [disabled|relay|hybrid]
  88
  89 dynamicdhcp     bool    1                       dynamically create leases
  90                                                 for DHCPv4 and DHCPv6
  91 router          list    <local address>         Routers to announce
  92                                                 accepts IPv4 only
  93 dns             list    <local address>         DNS servers to announce
  94                                                 accepts IPv4 and IPv6
  95 domain          list    <local search domain>   Search domains to announce
  96
  97 leasetime       string  12h                     DHCPv4 address leasetime
  98 start           integer 100                     DHCPv4 pool start
  99 limit           integer 150                     DHCPv4 pool size
 100
 101 ra_default      integer 0                       Override default route
 102                 0: default, 1: ignore no public address, 2: ignore all
 103 ra_management   integer 1                       RA management mode
 104                 0: no M-Flag but A-Flag, 1: both M and A, 2: M but not A
 105 ra_offlink      bool    0                       Announce prefixes off-link
 106 ra_preference   string  medium                  Route(r) preference
 107                 [medium|high|low]
 108 ndproxy_routing bool    1                       Learn routes from NDP
 109 ndproxy_slave   bool    0                       NDProxy external slave
 110
 111
 112 Sections of type host (static leases)
 113 Option          Type    Default                 Description
 114 ip              string                          IP-Address to lease
 115 mac             string                          MAC-address
 116 duid            string                          DUID in base16
 117 hostid          string                          IPv6 host identifier
 118 name            string                          Hostname
 119 leasetime       string                          DHCPv4/v6 leasetime
 120