It’s convenient, but it also means you’re guaranteed to have two “ip.addr” fields for each IPv4 header which means guaranteed ambiguity. Even worse, Wireshark has a completely made up “ip.addr” field, which is an alias for both “ip.src” and “ip.dst”. In any case a filter like “ip.src = 10.1.2.3” can be ambiguous.

Maybe you live on the edge and used scapy to create a packet with a hundred or a thousand layers of IP in IP nesting. You might be in an environment that uses some form of tunneling like GRE or one of the many VPN protocols, and even on simple networks ICMP errors carry the IPv4 header of the offending packet. You might assume that the packets on your network have one IPv4 header and therefore one source address, but that’s not necessarily the case. Within Wireshark that means using the “ip.src” filter field.

Suppose you want to filter on an IPv4 source address.

These improvements give you more control over the way that multiple occurrences of the same field are handled, let you do arithmetic, and many other things.įirst, let’s look at the way multiple field occurrences are handled. Display Filter Changesĭisplay filters are one of Wireshark’s defining features and 4.0 makes them more powerful and more consistent. I’ll cover some highlights here, but the release notes go into much greater detail. If you are a regular Wireshark user we recommend that you pay close attention to the release notes this time around, since it includes quite a few changes. Wireshark 4.0 was released today, and as you might have guessed from the version number, quite a few things have changed since 3.6.