I have a capture in which every frame starts with a proprietary header followed by ethernet frame (beginning with dest MAC and source MAC). I'm trying to discard this proprietary header using DLT USER but when I try to set "ethernet" or "ethics's" as payload protocol, I get a "dissector not found" error. How can I do ?
I did some digging in the source-code and the ethernet dissector registers itself with three protocol names:
So if you already know if the enbedded ethernet frames have a FCS, you can use eth_withoutfcs or eth_withfcs. If you don't know (or if it can be a mix), then you can use eth_maybefcs as the protocol.
Instead of using a custom DLT to discard this proprietary header while showing the packets in Wireshark, you can also remove the proprietary header from the pcap file by using editcap -C <headerlength> <old.pcap> <new.pcap>
This needs an update of the User's Guide.
Or we could register eth (as a duplicate of eth_maybefcs)? That would be much more intuitive than eth_maybefcs, even if it is mentioned in the UG, still a lot of non-RTFM in the world ;-)
Thanks a lot, this works perfectly.
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