9dbbb2829e
is required. PR: 33559 Submitted by: Marc Olzheim <marcolz@ilse.nl>
530 lines
19 KiB
Plaintext
530 lines
19 KiB
Plaintext
USAGE
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KAME Project
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$KAME: USAGE,v 1.33 2000/11/22 10:22:57 itojun Exp $
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$FreeBSD$
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This is an introduction of how to use the commands provided in the KAME
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kit. For more information, please refer to each man page.
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<<<ifconfig>>>
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A link-local address is automatically assigned to each interface, when
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the interface becomes up for the first time. Even if you find an interface
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without a link-local address, do not panic. The link-local address will be
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assigned when it becomes up (with "ifconfig IF up").
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If you do not see a link-local address assigned to an interface on "ifconfig
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up", the interface does not support IPv6 for some reasons - for example,
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if the interface does not support link-layer multicast (IFF_MULTICAST is not
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set), the interface cannot be used for IPv6.
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Some network drivers allow an interface to become up even without a
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hardware address (for example, PCMCIA network cards). In such cases, it is
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possible that an interface has no link-local address even if the
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interface is up. If you see such situation, please disable the
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interface once and then re-enable it (i.e. do `ifconfig IF down;
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ifconfig IF up').
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Pseudo interfaces (like "gif" tunnel device) will borrow IPv6
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interface identifier (lowermost 64bit of the address) from
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EUI64/IEEE802 sources, like ethernet cards. Pseudo interfaces will be
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able to get an IPv6 link-local address, if you have other "real"
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interface configured beforehand. If you have no EUI64/IEEE802 sources
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on the node, we have last-resort code in the kernel, which generates
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interface identifier from MD5(hostname). MD5(hostname) may not be suitable
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for your usage (for example, if you configure same hostname on both sides of
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gif tunnel, you will be doomed), and if so, you may need to configure
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link-local address manually.
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See RFC2472 for more discussion on how to generate an interface ID for
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pseudo interfaces.
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If you have a router announcing Router Advertisement,
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global addresses will be assigned automatically. So, neither
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"ifconfig" nor "prefix" is necessary for your *host* (non-router node).
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(Please refer to "sysctl" section for configuring a host to accept
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Router Advertisement.)
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If you want to set up a router, you need to assign global addresses
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for two or more interfaces by "ifconfig" or "prefix" (prefix command
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is described at next section).
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If you want to assign a global address by "ifconfig", don't forget to
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specify the "alias" argument to keep the link-local address.
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# ifconfig de0 inet6 3ffe:501:808:1:200:f8ff:fe01:6317 prefixlen 64 alias
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# ifconfig de0
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de0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
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inet6 fe80::200:f8ff:fe01:6317%de0 prefixlen 64 scopeid 0x1
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inet 163.221.202.12 netmask 0xffffff00 broadcast 163.221.202.255
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inet6 3ffe:501:808:1:200:f8ff:fe01:6317 prefixlen 64
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ether 00:00:f8:01:63:17
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media: 100baseTX status: active
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See also "/etc/rc.network6" for actual examples.
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<<prefix>>
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In the IPv6 architecture, an IPv6 address of an interface can be
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generated from a prefix assigned to the interface, and a
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link-dependent identifier for the interface. So assigning a full IPv6
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address by ifconfig is not necessary anymore, because user can only
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take care of prefix, by letting system take care of interface
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identifier.
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The newly added "prefix" command enables user to just assign prefixes
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for interfaces, and let your system automatically generate IPv6
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addresses. Prefixes added by the "prefix" command is maintained in
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the kernel consistently with prefixes assigned by Router
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Advertisement (in case of hosts) and with prefixes assigned by Router
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Renumbering (in case of routers). Manual assignment of prefixes or
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change of prefix properties take precedence over ones assigned by
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Router Advertisement or Router Renumbering.
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prefix command works only on routers.
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If you want to assign a prefix (and consequently address) manually, do
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as follows:
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# ifconfig de0
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de0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
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inet6 fe80::200:f8ff:fe01:6317%de0 prefixlen 64 scopeid 0x1
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inet 163.221.202.12 netmask 0xffffff00 broadcast 163.221.202.255
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ether 00:00:f8:01:63:17
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media: 100baseTX status: active
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# prefix de0 3ffe:501:808:1::
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# ifconfig de0
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de0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
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inet6 fe80::200:f8ff:fe01:6317%de0 prefixlen 64 scopeid 0x1
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inet 163.221.202.12 netmask 0xffffff00 broadcast 163.221.202.255
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inet6 3ffe:501:808:1:200:f8ff:fe01:6317 prefixlen 64
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ether 00:00:f8:01:63:17
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media: 100baseTX status: active
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To check assigned prefix, use the "ndp" command (See description of
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ndp command about its usage).
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# ndp -p
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3ffe:501:808:1::/64 if=de0
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flags=LA, vltime=2592000, pltime=604800, expire=Never, origin=RR
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No advertising router
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The "prefix" command also has node internal prefix renumbering
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ability.
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If you have multiple prefixes which have 3ffe:501:808:/48 at the top,
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and would like to renumber them to 3ffe:501:4819:/48, then use the
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"prefix" command with the "matchpr" argument and the "usepr" argument.
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Suppose that current state of before renumbering as follows:
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# ifconfig de0
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de0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
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inet6 fe80::200:f8ff:fe01:6317%de0 prefixlen 64 scopeid 0x1
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inet 163.221.202.12 netmask 0xffffff00 broadcast 163.221.202.255
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inet6 3ffe:501:808:1:200:f8ff:fe01:6317 prefixlen 64
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ether 00:00:f8:01:63:17
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media: 100baseTX status: active
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# ifconfig de1
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de1: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
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inet6 fe80::200:f8ff:fe55:7011%de1 prefixlen 64 scopeid 0x2
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inet 163.221.203.12 netmask 0xffffff00 broadcast 163.221.203.255
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inet6 3ffe:501:808:2:200:f8ff:fe55:7011 prefixlen 64
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ether 00:00:f8:55:70:11
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media: 100baseTX status: active
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# ndp -p
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3ffe:501:808:1::/64 if=de0
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flags=LA, vltime=2592000, pltime=604800, expire=Never, origin=RR
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No advertising router
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3ffe:501:808:2::/64 if=de1
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flags=LA, vltime=2592000, pltime=604800, expire=Never, origin=RR
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No advertising router
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Then do as follows:
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# prefix -a matchpr 3ffe:501:808:: mp_len 48 usepr 3ffe:501:4819:: up_uselen 48 change
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If command is successful, prefixes and addresses will be renumbered as
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follows.
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# ifconfig de0
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de0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
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inet6 fe80::200:f8ff:fe01:6317%de0 prefixlen 64 scopeid 0x1
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inet 163.221.202.12 netmask 0xffffff00 broadcast 163.221.202.255
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inet6 3ffe:501:4819:1:200:f8ff:fe01:6317 prefixlen 64
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ether 00:00:f8:01:63:17
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media: 100baseTX status: active
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# ifconfig de1
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de1: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
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inet6 fe80::200:f8ff:fe55:7011%de0 prefixlen 64 scopeid 0x2
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inet 163.221.203.12 netmask 0xffffff00 broadcast 163.221.203.255
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inet6 3ffe:501:4819:2:200:f8ff:fe55:7011 prefixlen 64
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ether 00:00:f8:55:70:11
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media: 100baseTX status: active
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# ndp -p
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3ffe:501:4819:1::/64 if=de0
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flags=LA, vltime=2592000, pltime=604800, expire=Never, origin=RR
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No advertising router
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3ffe:501:4819:2::/64 if=de1
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flags=LA, vltime=2592000, pltime=604800, expire=Never, origin=RR
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No advertising router
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See also "/etc/rc.network6" for actual examples.
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<<<route>>>
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If there is a router announcing Router Advertisement on a subnet,
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you need not to add a default route for your host by hand
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(Please refer to "sysctl" section to accept Router Advertisement).
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If you want to add a default route manually, do like:
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# route add -inet6 default fe80::200:a2ff:fe0e:7543%ed0
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"default" means ::/0. In other cases, if "prefixlen" is omitted, 64
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is assumed for "prefixlen" to get along with the aggregatable address.
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Note that, in IPv6, a link-local address should be used as gateway
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("fe80::200:a2ff:fe0e:7543%ed0" in the above). If you use global addresses,
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ICMPv6 redirect will not work properly. Also note that we use a special form
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of link-local address as gateway. See Section 1.3 of IMPLEMENTATION for
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more details.
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For ease of configuration we recommend you to avoid static routes and run
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a routing daemon (route6d for example) instead.
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<<<ping6>>>
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Reachability can be checked by "ping6". This "ping6" allows multicast
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for its argument.
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% ping6 -n -I ed0 ff02::1
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PING6(56=40+8+8 bytes) fe80::5254:ff:feda:cb7d --> ff02::1%ed0
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56 bytes from fe80::5254:ff:feda:cb7d%lo0, icmp_seq=0 hlim=64 time=0.25 ms
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56 bytes from fe80::2a0:c9ff:fe84:ed6c%ed0, icmp_seq=0 hlim=64 time=1.333 ms(DUP!)
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56 bytes from fe80::5254:ff:feda:d161%ed0, icmp_seq=0 hlim=64 time=1.459 ms(DUP!)
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56 bytes from fe80::260:97ff:fec2:80bf%ed0, icmp_seq=0 hlim=64 time=1.538 ms(DUP!)
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56 bytes from 3ffe:501:4819:2000:5054:ff:fedb:aa46, icmp_seq=0 hlim=255 time=1.615 ms(DUP!)
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<<<ping6 -w>>>
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Name resolution is possible by ICMPv6 node information query message.
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This is very convenient for link-local addresses whose host name cannot be
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resolved by DNS. Specify the "-w" option to "ping6".
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% ping6 -n -I ed0 -w ff02::1
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64 bytes from fe80::5254:ff:feda:cb7d%lo0: fto.kame.net
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67 bytes from fe80::5254:ff:feda:d161%ed0: banana.kame.net
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69 bytes from fe80::2a0:c9ff:fe84:ebd9%ed0: paradise.kame.net
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66 bytes from fe80::260:8ff:fe8b:447f%ed0: taroh.kame.net
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66 bytes from fe80::2a0:c9ff:fe84:ed6c%ed0: ayame.kame.net
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<<<traceroute6>>>
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The route for a target host can be checked by "traceroute6".
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% traceroute6 tokyo.v6.wide.ad.jp
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traceroute to tokyo.v6.wide.ad.jp (3ffe:501:0:401:200:e8ff:fed5:8923), 30 hops max, 12 byte packets
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1 nr60.v6.kame.net 1.239 ms 0.924 ms 0.908 ms
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2 otemachi.v6.wide.ad.jp 28.953 ms 31.451 ms 26.567 ms
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3 tokyo.v6.wide.ad.jp 26.549 ms 26.58 ms 26.186 ms
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If the -l option is specified, both address and name are shown in each line.
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% traceroute6 -l tokyo.v6.wide.ad.jp
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traceroute to tokyo.v6.wide.ad.jp (3ffe:501:0:401:200:e8ff:fed5:8923), 30 hops max, 12 byte packets
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1 nr60.v6.kame.net (3ffe:501:4819:2000:260:97ff:fec2:80bf) 1.23 ms 0.952 ms 0.92 ms
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2 otemachi.v6.wide.ad.jp (3ffe:501:0:1802:260:97ff:feb6:7ff0) 27.345 ms 26.706 ms 26.563 ms
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3 tokyo.v6.wide.ad.jp (3ffe:501:0:401:200:e8ff:fed5:8923) 26.329 ms 26.36 ms 28.63 ms
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<<<ndp>>>
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To display the current Neighbor cache, use "ndp":
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% ndp -a
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Neighbor Linklayer Address Netif Expire St Flgs Prbs
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nr60.v6.kame.net 0:60:97:c2:80:bf ed0 expired S R
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3ffe:501:4819:2000:2c0:cff:fe 0:c0:c:10:3a:53 ed0 permanent R
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paradise.v6.kame.net 52:54:0:dc:52:17 ed0 expired S R
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fe80::200:eff:fe49:f929%ed0 0:0:e:49:f9:29 ed0 expired S R
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fe80::200:86ff:fe05:80da%ed0 0:0:86:5:80:da ed0 expired S
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fe80::200:86ff:fe05:c2d8%ed0 0:0:86:5:c2:d8 ed0 9s R
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To flush all of the NDP cache entries, execute the following as root.
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# ndp -c
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To display the prefix list:
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% ndp -p
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3ffe:501:4819:2000::/64 if=ed0
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flags=LA, vltime=2592000, pltime=604800, expire=29d23h59m58s, origin=RA
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advertised by
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fe80::5254:ff:fedc:5217%ed0 (reachable)
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fe80::260:97ff:fec2:80bf%ed0 (reachable)
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fe80::200:eff:fe49:f929%ed0 (no neighbor state)
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To display the default router list:
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% ndp -r
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fe80::260:97ff:fec2:80bf if=ed0, flags=, expire=29m55s
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fe80::5254:ff:fedc:5217 if=ed0, flags=, expire=29m7s
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fe80::200:eff:fe49:f929 if=ed0, flags=, expire=28m47s
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<<<rtsol>>>
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To generate a Router Solicitation message right now to get global
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addresses, use "rtsol".
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# ifconfig ef0
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ef0: flags=8863<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST>
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link type ether 0:a0:24:ab:83:9b mtu 1500 speed 10Mbps
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media 10baseT status active
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inet6 fe80::2a0:24ff:feab:839b%ef0 prefixlen 64 scopeid 0x2
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# rtsol ef0
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# ifconfig ef0
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ef0: flags=8863<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST>
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link type ether 0:a0:24:ab:83:9b mtu 1500 speed 10Mbps
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media 10baseT status active
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inet6 fe80::2a0:24ff:feab:839b%ef0 prefixlen 64 scopeid 0x2
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inet6 3ffe:501:4819:2000:2a0:24ff:feab:839b prefixlen 64
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<<<rtsold>>>
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rtsold is a daemon version of rtsol. If you run KAME IPv6 on a laptop
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computer and frequently move with it, the daemon is useful since it watches
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the interface and sends router solicitations when the status of the interface
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changes. Note, however, that the feature is disabled by default. Please
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add -m option when invocation of rtsold.
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rtsold also supports multiple interfaces. For example, you can
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invoke the daemon as follows:
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# rtsold -m ep0 cnw0
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<<<netstat>>>
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To see routing table:
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# netstat -nr
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# netstat -nrl
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long format with Ref and Use. Note that bsdi4 does not support the
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-l option. You should use the -O option instead.
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<<<sysctl>>>
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If "net.inet6.ip6.accept_rtadv" is 1, Router Advertisement is
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accepted. This means that global addresses and default route are
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automatically set up. Otherwise, the announcement is rejected. The
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default value is 0. To set "net.inet6.ip6.accept_rtadv" to 1, execute
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as follows:
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# sysctl net.inet6.ip6.accept_rtadv=1
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<<<gifconfig>>>
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"gif" interface enables you to perform IPv{4,6} over IPv{4,6}
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protocol tunneling. To use this interface, you must specify the
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outer IPv{4,6} address by using gifconfig, like:
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# gifconfig gif0 163.221.198.61 163.221.11.21
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"ifconfig gif0" will configure the address pair used for inner
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IPv{4,6} header.
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It is not required to configure inner IPv{4,6} address pair. If
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you do not configure inner IPv{4,6} address pair, tunnel link is
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considered as un-numbered link and the source address of inner
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IPv{4,6} address pair will be borrowed from other interfaces.
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The following example configures un-numbered IPv6-over-IPv4 tunnel:
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# gifconfig gif0 10.0.0.1 10.0.0.1 netmask 255.255.255.0
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The following example configures numbered IPv6-over-IPv4 tunnel:
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# gifconfig gif0 10.0.0.1 10.0.0.1 netmask 255.255.255.0
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# ifconfig gif0 inet6 3ffe:501:808:5::1 3ffe:501:808:5::2 prefixlen 64 alias
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IPv6 spec allows you to use point-to-point link without global IPv6
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address assigned to the interface. Routing protocol (such as RIPng)
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uses link-local addresses only. If you are to configure IPv6-over-IPv4
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tunnel, you need not to configure an address pair for inner IPv6
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header. We suggest you to use the former example (un-numbered
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IPv6-over-IPv4 tunnel) to connect to 6bone for simplicity.
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Note that it is so easy to make an infinite routing loop using gif
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interface, if you configure a tunnel using the same protocol family
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for inner and outer header (i.e. IPv4-over-IPv4).
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Refer to gifconfig(8) for more details.
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<<<6to4>>>
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WARNING: malicious party can abuse 6to4 relay routers/sites, read through
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internet draft draft-itojun-ipv6-transition-abuse-xx.txt before configuring it.
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"stf" interface enables you to perform 6to4 IPv6-over-IPv4 encapsulation,
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as documented in draft-ietf-ngtrans-6to4-06.txt. See stf(4) for details.
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<<<inetd>>>
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Inetd supports AF_INET and AF_INET6 sockets, with IPsec policy
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configuration support.
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Refer to inetd(8) for more details.
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<<<IPsec>>>
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IPsec requires fairly complex configuration, so here we show transport
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mode only. http://www.kame.net/newsletter/ has more comprehensive
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examples.
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Let us setup security association to deploy a secure channel between
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HOST A (10.2.3.4) and HOST B (10.6.7.8). Here we show a little
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complicated example. From HOST A to HOST B, only old AH is used.
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From HOST B to HOST A, new AH and new ESP are combined.
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Now we should choose algorithm to be used corresponding to "AH"/"new
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AH"/"ESP"/"new ESP". Please refer to the "setkey" man page to know
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algorithm names. Our choice is MD5 for AH, new-HMAC-SHA1 for new AH,
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and new-DES-expIV with 8 byte IV for new ESP.
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Key length highly depends on each algorithm. For example, key
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length must be equal to 16 bytes for MD5, 20 for new-HMAC-SHA1,
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and 8 for new-DES-expIV. Now we choose "MYSECRETMYSECRET",
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"KAMEKAMEKAMEKAMEKAME", "PASSWORD", respectively.
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|
OK, let us assign SPI (Security Parameter Index) for each protocol.
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|
Please note that we need 3 SPIs for this secure channel since three
|
|
security headers are produced (one for from HOST A to HOST B, two for
|
|
from HOST B to HOST A). Please also note that SPI MUST be greater
|
|
than or equal to 256. We choose, 1000, 2000, and 3000, respectively.
|
|
|
|
|
|
(1)
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|
HOST A ------> HOST B
|
|
|
|
(1)PROTO=AH
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|
ALG=MD5(RFC1826)
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|
KEY=MYSECRETMYSECRET
|
|
SPI=1000
|
|
|
|
(2.1)
|
|
HOST A <------ HOST B
|
|
<------
|
|
(2.2)
|
|
|
|
(2.1)
|
|
PROTO=AH
|
|
ALG=new-HMAC-SHA1(new AH)
|
|
KEY=KAMEKAMEKAMEKAMEKAME
|
|
SPI=2000
|
|
|
|
(2.2)
|
|
PROTO=ESP
|
|
ALG=new-DES-expIV(new ESP)
|
|
IV length = 8
|
|
KEY=PASSWORD
|
|
SPI=3000
|
|
|
|
Now, let us setup security association. Execute "setkey" on both HOST
|
|
A and B:
|
|
|
|
# setkey -c
|
|
add 10.2.3.4 10.6.7.8 ah 1000 -m transport -A keyed-md5 "MYSECRETMYSECRET" ;
|
|
add 10.6.7.8 10.2.3.4 ah 2000 -m transport -A hmac-sha1 "KAMEKAMEKAMEKAMEKAME" ;
|
|
add 10.6.7.8 10.2.3.4 esp 3000 -m transport -E des-cbc "PASSWORD" ;
|
|
^D
|
|
|
|
Actually, IPsec communication doesn't process until security policy
|
|
entries will be defined. In this case, you must setup each host.
|
|
|
|
At A:
|
|
# setkey -c
|
|
spdadd 10.2.3.4 10.6.7.8 any -P out ipsec
|
|
ah/transport/10.2.3.4-10.6.7.8/require ;
|
|
^D
|
|
|
|
At B:
|
|
spdadd 10.6.7.8 10.2.3.4 any -P out ipsec
|
|
esp/transport//require
|
|
ah/transport//require ;
|
|
^D
|
|
|
|
To utilize the security associations installed into the kernel, you
|
|
must set the socket security level by using setsockopt().
|
|
This is per-application (or per-socket) security. For example,
|
|
the "ping" command has the -P option with parameter to enable AH and/or ESP.
|
|
|
|
For example:
|
|
% ping -P "out ipsec \
|
|
ah/transport//use \
|
|
esp/tunnel/10.0.1.1-10.0.1.2/require" 10.0.2.2
|
|
|
|
If there are proper SAs, this policy specification causes ICMP packet
|
|
to be AH transport mode inner ESP tunnel mode like below.
|
|
|
|
HOST C -----------> GATEWAY D ----------> HOST E
|
|
10.0.1.1 10.0.1.2 10.0.2.1 10.0.2.2
|
|
| | | |
|
|
| ======= ESP ======= |
|
|
==================== AH ==================
|
|
|
|
|
|
<<<EDNS0>>>
|
|
|
|
EDNS0 is defined in RFC2671. With EDNS0, the resolver library can tell DNS
|
|
server of its receiving buffer size, and permit DNS server to transmit large
|
|
reply packet. EDNS0 is necessary to take advantage of larger minimum MTU
|
|
in IPv6. KAME libinet6 includes resolver side support for EDNS0.
|
|
Server side support for EDNS0 is included in ISC BIND9.
|
|
|
|
query packet with EDNS0
|
|
tells receive buffer size
|
|
KAME box -----------------------------> BIND9 DNS server
|
|
KAME box <----------------------------- BIND9 DNS server
|
|
can transmit jumbo reply, since DNS server
|
|
knows receive buffer size of KAME box
|
|
|
|
How to play with it:
|
|
- prepare KAME box and BIND9 DNS server (can be a same node)
|
|
- add the following into /etc/resolv.conf on KAME box:
|
|
options edns0 <--- enables EDNS0
|
|
nameserver <IPv4 or v6 address of BIND9 box>
|
|
- run applications compiled with libinet6 (like /usr/local/v6/bin/telnet),
|
|
see EDNS0 packet fly on the wire by tcpdump or some other method.
|
|
|
|
Caveats:
|
|
- BIND 4/8 DNS server will choke with EDNS0 packet, so you must not
|
|
turn the option on if you have BIND 4/8 DNS server. If you enable
|
|
"options edns0" against BIND 4/8 DNS server, you will never be able
|
|
to resolve names.
|
|
- If you use IPv6 UDP as DNS transport, path MTU discovery may
|
|
affect the traffic. KAME box tries to fragment packet to 1280
|
|
bytes, however, BIND9 may not.
|
|
- Some of our platforms do not use our extended resolver code in libinet6.
|
|
See COVERAGE for detail.
|
|
|
|
|
|
<<Further readings>>
|
|
|
|
http://www.netbsd.org/Documentation/network/ipv6/
|
|
Even if you are on non-netbsd operating system, the URL should be
|
|
useful.
|
|
http://www.kame.net/
|
|
|
|
<end of USAGE>
|