nexmonster/nexmon_csi

The capture file appears to be damaged or corrupt. (vwr: Invalid data length 3485744 (runs past the end of the record))

Opened this issue · 6 comments

environment
Ubuntu 22.04
ASUS RT-AC86U

I referred to the code listed and successfully captured it with tcpdump.

ssh admin@IP address "/jffs/tcpdump -i eth6 dst port 5500" > ~/csi_data.pcap

and loaded the saved file with wireshark, I get the following error.
I am having trouble solving the problem and would appreciate your help.

image

As for the tcpdump log, this is what it looks like, so you should be able to get it.

15:33:04.163366 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.166634 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.169911 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.173185 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.176385 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.179644 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.182920 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.186195 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.189472 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.192748 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.196023 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.199298 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.202491 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.205757 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.209033 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.212311 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.215725 00:00:77:6c:31:00 (oui Unknown) > 41:00:00:00:90:00 (oui Unknown) Null Information, send seq 0, rcv seq 0, Flags [Command], length 160
15:33:04.215732 00:00:77:6c:31:00 (oui Unknown) > 41:00:00:00:90:00 (oui Unknown) Null Information, send seq 0, rcv seq 0, Flags [Command], length 158
15:33:04.218763 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042
15:33:04.222037 IP 10.10.10.10.5500 > 255.255.255.255.5500: UDP, length 1042

Still no resolution.
Please let me know when you have time.
@zeroby0

No idea. Try plugging in a usb into the router and saving the pcap into it directly.

Or use nexmonster/relay to forward the csi packets to your laptop and store them on the laptop with tcpdump

Okay, Thank you very much.

I connected the USB to the router and tried saving the pcap directly, but the saved file was an empty file with 0 bytes.
Is there a solution?

No idea. Hard to debug without access to device.