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Hey np. Also, Wireshark and also tshark iirc support custom protocol dissectors; "How can I add a custom protocol analyzer to wireshark?" https://stackoverflo

Hey np. Also, Wireshark and also tshark iirc support custom protocol dissectors; "How can I add a custom protocol analyzer to wireshark?" https://stackoverflow.com/questions/4904991/how-can-i-add-a-custom-protocol-analyzer-to-wireshark https://stackoverflow.com/questions/4904991/how-can-i-add-a-... What can the pcap files contain?

0ops 2y ago
I'm sure this could be implemented using the Python bindings as the stored events contain the raw packet. Pcap conversion can also be used (it uses the same raw packet) for reusing existing tools like Wireshark and (I'm not familiar with that but I guess that would work) existing custom protocol dissectors.
cacheline 2y ago
the pcap-ng file will contain packets (l2/l3/l4 and so forth, but up to 255 bytes), each annotated with a comment that tells you from what kernel function or tracepoint the packet was "captured" from. For the time being you can generate pcapng files filtering packets based on a single probe (e.g. all filtered/tracked packets hitting `net:net_dev_start_xmit`). You can then use wireshark (or any tool you prefer) to dissect and further process. Custom dissectors should not be required.
- westurner 2y ago
  Can Wireshark parse comments in pcapng files, even with a dissector? /? ' https://www.google.com/search?q=Can+Wireshark+parse+comments+in+pcap+files https://www.google.com/search?q=Can+Wireshark+parse+comments... : frame.comment contains "Your string" And there's apparently a way to add a custom column to display frame.comment from pcapng traces in wireshark
  - cacheline 2y ago
    yep. For Wireshark/Tshark, display filters (including "frame.comment contains ...") can be used as usual. Of course, if your pcap file contains only frames with the same comment, that expression is not particularly useful, but you can merge multiple files with e.g. mergecap. The pcap subcommand, though, will be extended to allow extracting packets from multiple probes in a single run.

0ops 2y ago

I'm sure this could be implemented using the Python bindings as the stored events contain the raw packet. Pcap conversion can also be used (it uses the same raw packet) for reusing existing tools like Wireshark and (I'm not familiar with that but I guess that would work) existing custom protocol dissectors.

cacheline 2y ago

the pcap-ng file will contain packets (l2/l3/l4 and so forth, but up to 255 bytes), each annotated with a comment that tells you from what kernel function or tracepoint the packet was "captured" from. For the time being you can generate pcapng files filtering packets based on a single probe (e.g. all filtered/tracked packets hitting `net:net_dev_start_xmit`). You can then use wireshark (or any tool you prefer) to dissect and further process. Custom dissectors should not be required.

westurner 2y ago
Can Wireshark parse comments in pcapng files, even with a dissector? /? ' https://www.google.com/search?q=Can+Wireshark+parse+comments+in+pcap+files https://www.google.com/search?q=Can+Wireshark+parse+comments... : frame.comment contains "Your string" And there's apparently a way to add a custom column to display frame.comment from pcapng traces in wireshark
- cacheline 2y ago
  yep. For Wireshark/Tshark, display filters (including "frame.comment contains ...") can be used as usual. Of course, if your pcap file contains only frames with the same comment, that expression is not particularly useful, but you can merge multiple files with e.g. mergecap. The pcap subcommand, though, will be extended to allow extracting packets from multiple probes in a single run.