There is a Linux machine (A
) running pptpd inside a university network behind a firewall but with real IP. I have no access or any knowledge of IP distribution in this network, so I can't just set remoteip X.Y.Z.200-250
in pptpd config, since it might cause conflicts. I wonder whether it is possible to create a virtual hub for all connected VPN clients, which is then NATed to the real network.
Here is some clumpsy ascii grpaphics illustrating what I want to achieve:
PPTP-client ---\ ________________ ________________________
\ | 10.0.0.0/24 | |10.0.0.0/24 real ip|
PPTP-client ----->| Virt. hub (A) |----|ethX A eth0|----- Outside world
/ |_______________| |_______________________|
PPTP-client ---/
Googling shows that PacketiX.NET and UT-VPN have such built-in capabilities, but I have no idea of how to do it with ordinary pptpd. I've tried creating dummy interface, configuring it with static IP and then giving to pptp-client the IPs from this interface subnet, but with no success.
Usage of other vpn-servers is problematic since quite paranoid firewall settings and me having to use wetware ssh server for any operations on A
.