0
votes
0answers
60 views

virtual NIC, local routing and linux kernel routing table

from this article´╝Ü http://backreference.org/2010/03/26/tuntap-interface-tutorial/ the author created a tun interface # openvpn --mktun --dev tun2 # ip link set tun2 up # ip addr add 10.0.0.1/24 dev ...
0
votes
1answer
124 views

Is there a way to allow specific permissions to a non-root user?

I have a program that, at some point, create/destroys tun/tap virtual adapters. Obviously, for these specific operations this program requires root privileges. According to the program ...
2
votes
2answers
1k views

How can I configure openvpn to proxy traffic only for processes that bind to the tun interface?

I'm trying to configure openvpn so that only traffic from certain processes goes over the vpn, but those processes could connect to anywhere. I'm trying to do that by having openvpn not do any route ...
3
votes
1answer
484 views

Why doesn't TUN device have BROADCAST flag?

When creating a TUN device in Linux, on my machine the created TUN device has following flags: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> Clearly MULTICAST is listed in there but not ...
0
votes
1answer
1k views

How's the routing done in a very simple OpenVPN setup?

I've entirely configured (remotely) a Debian GNU/Linux dedicated server hosted in a professional capacity and I've got a network routing question (which AFAICT precisely fits the FAQ of serverfault). ...
1
vote
1answer
639 views

IP Packet Capture/Manipulation via TUN/TAP

I'm trying to capture and manipulate incoming IP packets (via eth0 interface) by using a TUN device (since I'm only concerned with IP layer). The first step I think is 1:1 packet forwarding from eth0 ...
2
votes
1answer
8k views

OpenVPN Cannot allocate TUN/TAP dev dynamically

OpenVPN clients work fine when they're started by /etc/init.d/openvpn for the first time, but they can't reconnect if the master server is restarted. This is the error I get in syslog: ...
3
votes
2answers
3k views

OpenVPN with iptables and a tun interface

With an openvpn tunnel that uses a tun device, what iptables rules allow the encapsulated traffic through and what rules control the packets after encapsulation? Basically, I am wondering how the ...
1
vote
1answer
3k views

How do I debug routing problems from a virtual tun0 device?

I have a program (written by me) that creates a tun0 device and sets up a route so that packets destined for the 172.16.1.0/24 subnet can be read from this device. I'm trying to go in the other ...
0
votes
2answers
2k views

Cannot open TUN/TAP dev

Can someone please help me with this? I have a linux 2.6.9 server (I know it's outdated, but it has some special modules and so kernel cannot be updated/recompiled/etc), and I need to have a tun/tap ...