Cannot set tap interface up using C++

Asked Dec 23 '18 at 08:28

Active Jan 05 '19 at 07:55

Viewed 403 times

I was able to create a persistent tap interface using this reference. Now I am trying to make the interface up using like this:

fd = iff_alloc(tap_name, IFF_TAP|IFF_NO_PI|IFF_UP);

However, I still see that the interface is down when I use the command ip link show:

`~/eclipse-workspace/RTI-swapper$ ip link show  | grep  tap0

6: tap0: <POINTOPOINT,MULTICAST,NOARP> mtu 1500 qdisc pfifo_fast state 
DOWN mode DEFAULT group default qlen 500`

Also, I am unable to see this interface in Wireshark. I can only see a tap interface on Wireshark when I create it manually from the terminal, for example:

openvpn --mktun --dev tap0
ip link set tap0 up
ip addr add 10.0.0.1/24 dev tap0

Could anyone help me know how to make a new tap interface visible to wireshark from my C++ code ?

edited Dec 30 '18 at 10:40

asked Dec 23 '18 at 08:28

Ahmed Hussein

1

what is `if_alloc` function here? – miradham Dec 24 '18 at 02:35
It stands for interface allocate. It is equivalent to `tun_alloc` in the reference link – Ahmed Hussein Dec 24 '18 at 06:44

Cannot set tap interface up using C++

0 Answers0