implement a decoder for MVRP (EtherType 0x88f5)

[Gunni]

Please add support for 802.1ak.

Right now it just returns an unknown ethertype error.

[guyharris]

What do you mean by "an unknown ether type error"? What is the precise error that is reported? (If you're seeing it in tcpdump, it might be a lack of support in tcpdump rather than in libpcap, which cares relatively little about Ethertypes - it knows a few, such as 0x0800 and 0x86dd, which it uses if you use filters such as ip and ip6, but it can also be given a filter such as ether proto 0x88f5 to capture only MVRP packets.

[guyharris]

In particular, tcpdump will print "Unknown Ethertype (0x88f5)" for an Ethernet packet with an unknown Ethertype value; a case-insensitive regex search for "unknown ether *type" in the libpcap source found nothing.

Presumably the issue is that tcpdump doesn't support MVRP, so I'm moving this to the tcpdump issues list.

[guyharris]

Do you have a network capture with a sample of MVRP traffic that we can use to test an added MVRP dissector?

[guyharris]

So that's 802.1Q-2022 11.2 "Multiple VLAN Registration Protocol (MVRP)", and probably 10. "Multiple Registration Protocol (MRP) and Multiple MAC Registration Protocol (MMRP)" as well.

[Gunni]

1. Yes this was tcpdump, I went upstream without checking. My bad.
2. Yes I have a pcap, I can get it tomorrow.

[guyharris]

1. Yes this was tcpdump, I went upstream without checking. My bad.

Two different upstreams, and it might not necessarily be obvious that libpcap doesn't do the dissection.

3. Yes I have a pcap, I can get it tomorrow.

Great! Thanks.

[Gunni]

Here is the PCAP.

Github wasn't accepting pcap files and changing file extensions to bypass that is hacky.

EDIT: Removed mega link.

[guyharris]

Github wasn't accepting pcap files and changing file extensions to bypass that is hacky.

I've filed a complaint about not being able to attach source code files (!); I've added a comment about network traffic captures.

[fxlb]

Github wasn't accepting pcap files and changing file extensions to bypass that is hacky.

Just add .txt after .pcap(ng). Please do it to keep all information in this page.

[infrastation]

After decades of frantic development some Internet communication channels are still not entirely dislike 7-bit lines... base64, xxd -p or even hexdump can keep this mini-BBS running meanwhile.