How to access ethernet/mac header in link layer 2 dissector

asked 2018-06-19 13:50:08 +0000

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I want to calculate a CRC32 like specified in 802.3 over the complete ethernet paket including the 14 byte ethernet/mac header. I've implemented a link layer 2 dissector but I am only able to access bytes 14 onwards. Can someone tell me how to access bytes 0-13 from the dissector? Or how to accomplish to perform a CRC check another way? Thank you very much!

Best regards, Christoph

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I've implemented a link layer 2 dissector

For what link-layer protocol? Wireshark already has a dissector for Ethernet, and it already does check the CRC if it's present.

Guy Harris gravatar imageGuy Harris ( 2018-06-20 05:47:37 +0000 )edit

thank you very much for that hint. I had to activate the FCS option in the ethernet dissector options page.

christoph1986 gravatar imagechristoph1986 ( 2018-06-21 10:31:44 +0000 )edit