IP dynamic address hack-port v0.03

This stuff allows diald ONESHOT connections to get established bydynamically 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[1] and forwarding interface has changed:

  1. Socket (and packet) source address is rewritten ON RETRANSMISSIONSwhile in SYN_SENT state (diald-box processes).

  2. Out-bounded MASQueraded source address changes ON OUTPUT (wheninternal host does retransmission) until a packet from outside isreceived by the tunnel.

This is specially helpful for auto dialup links (diald), where theactual outgoing address is unknown at the moment the link isgoing up. So, thesame (local AND masqueraded) connections requests thatbring the link up will be able to get established.

[1]

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>