unpack_gre flag in sflow_plugin not working for IPv6

[Nuyek]

IPv6 is not unpacked correctly with the unpack_gre flag with the sflow_plugin.

Fastnetmon Version: 1.2.7 OS: Debian 12

PCAP data: https://files.nuyek.com/u/8xv86u.pcap

[pavel-odintsov]

Hello!

Thank you!

I can replicate error:

2024-07-15 18:08:37,684 [DEBUG] sflow: Cannot parse nested packet using ng parser: broken_gre
2024-07-15 18:08:37,684 [DEBUG] sflow: Cannot parse nested packet using ng parser: broken_gre
2024-07-15 18:08:37,684 [DEBUG] sflow: Cannot parse nested packet using ng parser: broken_gre
2024-07-15 18:08:37,684 [DEBUG] sflow: Cannot parse nested packet using ng parser: broken_gre
2024-07-15 18:08:37,684 [DEBUG] sflow: Cannot parse nested packet using ng parser: broken_gre
2024-07-15 18:08:37,684 [DEBUG] sflow: Cannot parse nested packet using ng parser: broken_gre

[pavel-odintsov]

It's slightly tricky to investigate this case as it's nested deeply in sFlow packet.

Can you capture pcap of GRE with IPv6 inside? Few packets should be enough.

Thank you!

[Nuyek]

Here's the PCAP data with some GRE IPv6.

https://files.nuyek.com/u/0P6IJ8.pcap