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
  66
  67 Sections of type dhcp (configure DHCP / DHCPv6 / RA / NDP service)
  68
  69 Option          Type    Default                 Description
  70 interface       string  <name of UCI section>   logical OpenWrt interface
  71 ifname          string  <resolved from logical> physical network interface
  72 networkid       string  same as ifname          compat. alias for ifname
  73 ignore          bool    0                       do not serve this interface
  74                                                 unless overridden by ra, ndp,
  75                                                 dhcpv4 or dhcpv6 options
  76 master          bool    0                       is a master interface
  77                                                 for relaying
  78
  79 ra              string  disabled                Router Advert service
  80                 [disabled|server|relay|hybrid]
  81 dhcpv6          string  disabled                DHCPv6 service
  82                 [disabled|server|relay|hybrid]
  83 dhcpv4          string  disabled                DHCPv4 service
  84                 [disabled|server]
  85 ndp             string  disabled                Neighbor Discovery Proxy
  86                 [disabled|relay|hybrid]
  87
  88 dynamicdhcp     bool    1                       dynamically create leases
  89                                                 for DHCPv4 and DHCPv6
  90 router          list    <local address>         Routers to announce
  91                                                 accepts IPv4 only
  92 dns             list    <local address>         DNS servers to announce
  93                                                 accepts IPv4 and IPv6
  94 domain          list    <local search domain>   Search domains to announce
  95
  96 leasetime       string  12h                     DHCPv4 address leasetime
  97 start           integer 100                     DHCPv4 pool start
  98 limit           integer 150                     DHCPv4 pool size
  99
 100 ra_default      integer 0                       Override default route
 101                 0: default, 1: ignore no public address, 2: ignore all
 102 ra_management   integer 1                       RA management mode
 103                 0: no M-Flag but A-Flag, 1: both M and A, 2: M but not A
 104 ra_offlink      bool    0                       Announce prefixes off-link
 105 ra_preference   string  medium                  Route(r) preference
 106                 [medium|high|low]
 107 ndproxy_routing bool    1                       Learn routes from NDP
 108 ndproxy_slave   bool    0                       NDProxy external slave
 109
 110
 111 Sections of type host (static leases)
 112 Option          Type    Default                 Description
 113 ip              string                          IP-Address to lease
 114 mac             string                          MAC-address
 115 duid            string                          DUID in base16
 116 hostid          string                          IPv6 host identifier
 117 name            string                          Hostname
 118 leasetime       string                          DHCPv4/v6 leasetime
 119