search

schollz / howmanypeoplearearound

Count the number of people around you :family_man_man_boy: by monitoring wifi signals :satellite:
MIT License
6.88k stars 385 forks source link

Unable to capture packets [Malformed packet] #20

Open sanketh95 opened 7 years ago

sanketh95 commented 7 years ago

Hi @schollz ,

First of all, great work here. I found this project really interesting.

Getting to the point, I was trying to run the command and it kept saying that no signals were found. I ran the tshark command manually to see what's wrong. It appears that the packets are malformed and I suspect it has something to do with the addition of radiotap headers. See the output below.

% tshark -i wlp3s0 -I -a duration:60
Capturing on 'wlp3s0' 1 0.000000000 -> WLAN 87 Radiotap Capture v255, Length 65535[Malformed Packet] 2 0.052283376 -> WLAN 136 Radiotap Capture v255, Length 65535[Malformed Packet] 3 0.241639018 -> WLAN 90 Radiotap Capture v255, Length 65535[Malformed Packet] 4 0.302993069 -> WLAN 136 Radiotap Capture v255, Length 65535[Malformed Packet] 5 0.553821626 -> WLAN 136 Radiotap Capture v255, Length 65535[Malformed Packet]

I was hoping you could help me with this. Thanks a ton !

Sanketh

schollz commented 7 years ago

It seems there could be a couple reasons and sounds like you have to investigate with a network trace.

schollz commented 7 years ago

@sanketh95 were you able to resolve this?

sanketh95 commented 7 years ago

I was. I seems like the issue was in the way I was putting my wireless card in monitor mode. The -I option to tshark was somehow unable to do it. However, I was able to manually put it in monitor mode using aircrack-ng. The script started working after that.