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+.. SPDX-License-Identifier: GPL-2.0
+
+==================================
+IP dynamic address hack-port v0.03
+==================================
+
+This stuff allows diald ONESHOT connections to get established by
+dynamically changing packet source address (and socket's if local procs).
+It is implemented for TCP diald-box connections(1) and IP_MASQuerading(2).
+
+If enabled\ [#]_ and forwarding interface has changed:
+
+ 1) Socket (and packet) source address is rewritten ON RETRANSMISSIONS
+ while in SYN_SENT state (diald-box processes).
+ 2) Out-bounded MASQueraded source address changes ON OUTPUT (when
+ internal host does retransmission) until a packet from outside is
+ received by the tunnel.
+
+This is specially helpful for auto dialup links (diald), where the
+``actual`` outgoing address is unknown at the moment the link is
+going up. So, the *same* (local AND masqueraded) connections requests that
+bring the link up will be able to get established.
+
+.. [#] At boot, by default no address rewriting is attempted.
+
+ To enable::
+
+ # echo 1 > /proc/sys/net/ipv4/ip_dynaddr
+
+ To enable verbose mode::
+
+ # echo 2 > /proc/sys/net/ipv4/ip_dynaddr
+
+ To disable (default)::
+
+ # echo 0 > /proc/sys/net/ipv4/ip_dynaddr
+
+Enjoy!
+
+Juanjo <jjciarla@raiz.uncu.edu.ar>