1 .\" Copyright (c) 2005 Gleb Smirnoff <glebius@FreeBSD.org>
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32 .Nd "NAT netgraph node type"
38 node performs network address translation (NAT) of packets
44 engine for packet aliasing.
45 At this moment it supports only the basic functionality of the library.
47 This node type has two hooks:
48 .Bl -tag -width indent
50 Packets received on this hook are considered outgoing and will be
51 masqueraded to a configured address.
53 Packets coming on this hook are considered incoming and will be
57 This node type supports the generic control messages, plus the following:
58 .Bl -tag -width indent
59 .It Dv NGM_NAT_SET_IPADDR Pq Li setaliasaddr
60 Configure aliasing address for a node.
61 After both hooks have been connected and aliasing address was configured,
62 a node is ready for aliasing operation.
65 This node shuts down upon receipt of a
67 control message, or when both hooks are disconnected.
69 In the following example, the packets are injected into a
74 .Bd -literal -offset indent
76 ngctl mkpeer ipfw: nat 60 out
77 ngctl name ipfw:60 nat
78 ngctl connect ipfw: nat: 61 in
79 ngctl msg nat: setaliasaddr x.y.35.8
81 # Divert traffic into NAT node
82 ipfw add 300 netgraph 61 all from any to any in via fxp0
83 ipfw add 400 netgraph 60 all from any to any out via fxp0
85 # Let packets continue with after being (de)aliased
86 sysctl net.inet.ip.fw.one_pass=0
91 node can be inserted right after the
94 In the following example, we perform masquerading on a
95 serial line with HDLC encapsulation.
96 .Bd -literal -offset indent
97 /usr/sbin/ngctl -f- <<-SEQ
98 mkpeer cp0: cisco rawdata downstream
100 mkpeer hdlc: nat inet in
102 mkpeer nat: iface out inet
103 msg nat: setaliasaddr x.y.8.35
105 ifconfig ng0 x.y.8.35 x.y.8.1
115 node type was implemented in
118 .An Gleb Smirnoff Aq glebius@FreeBSD.org