Unable to get libpcap (and by extension sharppcap) to work on Ubuntu 20.04

[mkinalamscreen]

Unable to get libpcap (and by extension sharppcap) to work on Ubuntu 20.04

[kayoub5]

• libpcap version that you installed in Linux?
• are you using sudo/root?

[mkinalamscreen]

Hi, I'm using version 1.9.1-3 for libpcap0.8

I'm executing the dotnet app with sudo. I've tried publishing both Linux x86 and portable files and have gotten the same result.

[kayoub5]

from exception, it seems your wifi adapter does not support promiscuous mode, so you need to change the mode in the Open function

[mkinalamscreen]

I've just tried it now, same error. All of my interfaces were set with promiscuous mode turned off. I also tried a different interface but it resulted in the same exception.

[kayoub5]

• does tcpdump work on that interface?
• can you capture on lo and any interfaces?
• you need to change the mode in C# code (it is promiscuous by default)

[mkinalamscreen]

I've just installed tcpdump and ran sudo tcpdump -i wwan0, it returned raw packages:

I tried executing the CreateCaptureFile program on lo and any interfaces, same issue.

I had removed the promiscuous mode from the open function as per your previous comment.

One thing to note is that the Ubuntu version we are using is restricted in terms of privileges and functions for security reasons. We're not working on a clean/fresh install of Ubuntu.

[kayoub5]

Ok, remove all other modes, put promiscuous back.
libpcap/sharppcap is complaining about lack of support for NoCaptureLocal and DataTransferUdp

[mkinalamscreen]

Brilliant, it's working now! Thank you for your help.