1.. SPDX-License-Identifier: GPL-2.0
 2
 3==================================
 4IP dynamic address hack-port v0.03
 5==================================
 6
 7This stuff allows diald ONESHOT connections to get established by
 8dynamically changing packet source address (and socket's if local procs).
 9It is implemented for TCP diald-box connections(1) and IP_MASQuerading(2).
10
11If enabled\ [#]_ and forwarding interface has changed:
12
13  1)  Socket (and packet) source address is rewritten ON RETRANSMISSIONS
14      while in SYN_SENT state (diald-box processes).
15  2)  Out-bounded MASQueraded source address changes ON OUTPUT (when
16      internal host does retransmission) until a packet from outside is
17      received by the tunnel.
18
19This is specially helpful for auto dialup links (diald), where the
20``actual`` outgoing address is unknown at the moment the link is
21going up. So, the *same* (local AND masqueraded) connections requests that
22bring the link up will be able to get established.
23
24.. [#] At boot, by default no address rewriting is attempted.
25
26  To enable::
27
28     # echo 1 > /proc/sys/net/ipv4/ip_dynaddr
29
30  To enable verbose mode::
31
32    # echo 2 > /proc/sys/net/ipv4/ip_dynaddr
33
34  To disable (default)::
35
36     # echo 0 > /proc/sys/net/ipv4/ip_dynaddr
37
38Enjoy!
39
40Juanjo  <jjciarla@raiz.uncu.edu.ar>