Transparent VPN on Linux?

Hi,

FreeS/WAN can be used to set up a network-to-network tunnel from a given
subnet to the rest of the world:
10.1.0.0/24 <-----> 0.0.0.0

Does anyone know if there is a way to set up a tunnel from 'anywhere to
anywhere'? (that is, any packet sent to the ipsec0 interface would be
forwarded through the tunnel, without requiring any more configuration?)

Thanks for any help,

Regards.





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