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Comment by armitron | Hacker News Reader

Wild exaggeration. Wireshark is very limited in what it can do and has gained few if any new power-user features (especially when it comes to extensibility and programmability) in more than a decade of development. The macOS-specific functionality in this very post has been available for years.

Anyone who relies on non-trivial packet capture or processing workflows, ditches Wireshark (optionally reusing dissectors) and writes custom tooling (which is very easy to do).

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Even the dissector stuff feels so.. broken? unmaintained? The lua api is very annoying to use and python support was removed over a decade ago. Have not used the C API so maybe thats just what most people use and its good, but for my usecase I usually just want to quickly sketch out a view for a custom protocol that I can see in the UI.

I would absolutely love for someone to write a good alternative to wireshark.

As a constant Wireshark user who's personally thanked Gerald Combs for this tool, we don't need an alternative to wireshark, just some architectural refactors. Many packet dissection fields are embarrassingly parallel, but because some of them can involve previous/future packets, wireshark does all packet dissection in a single thread. So when I scoop up 10M packets it can take 20 minutes for the GUI to load them all with a single core, while 100 other cores on the same machine sit idle.

Once loaded, you have to be super careful. One update to the filter bar, like "!icmp" and you'll have to wait another 20 minutes for all the dissectors to be re-run (for some reason.)

As a previous commenter stated, if you work with Wireshark a lot, you eventually write your own tool for your performance needs. It feels magical to have a 3-page C program sitting over libpcap giving reports in miliseconds that would take wireshark minutes.

FWIW, Wireshark 4.6.0 ships with `sharkd`, which encapsulates all the EPAN dissectors into a simple to use server that accepts JSON-RPC requests.

It is quite easy to write specialized performance tools on top of `sharkd`, and since it has the entire power of the EPAN (including statistics, charts etc.), using `sharkd` is significantly more effective than reading straight from libpcap.

https://wiki.wireshark.org/Development/sharkd

The `sharkd` has been around for quite some while, but until recently one had to build it from source. But now it is included in Wireshark DMG, so it is easier to use.

You're right, and I didnt mean to sound dismissive of the great work that has been put into wireshark. I agree with you on the refactoring comment, and if that's something that can be solved in the current codebase and something I can help contribute towards with donations I would be perfectly fine with this outcome as well.

As it stands though, using the gui bits of the wireshark family of tools is just painful, and slow (as you stated)

>It feels magical to have a 3-page C program sitting over libpcap giving reports in miliseconds that would take wireshark minutes.

Any demos available of something like this?

Sadly proprietary, but the core of it was to open a file with pcap_open_offline() [0], and then calling pcap_next() from a loop and reading a few bits out of the packet buffer. With NVMe disks, the information I needed was instantaneous for a 10M packet file.

https://manpages.debian.org/stretch/libpcap0.8-dev/pcap_open...

> The macOS-specific functionality in this very post has been available for years.

Can you provide a reference? From what I can see this dissection was only added about five months ago: https://gitlab.com/wireshark/wireshark/-/commit/389f6356c9d5...

(And just hit release with 4.6.0.)

And I know with certainty that it did not work when I wrote my previous blog post about this, back in 2021.

So, from what I can see, the specific functionality to dissect Darwin metadata in pcapng captures, from macOS' tcpdump, has not been "...available for years.".

Without using Wireshark seems to be what they meant

I think it is not an exaggeration to say that without Wireshark, so much of modern computing would never have been developed and we would be stuck in the past. The amount of visibility it gives is immense. I have used it for years, decades now.

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