Sometimes the packets you’re interested in aren’t in a nice pcap or pcapng file that you can just open with Wireshark, and are instead buried in a hex dump. Sorting has been improved, you can now hide columns, filter on stream IDs, and export data as JSON. For example, you can tear off tabs - you can now see TCP and UDP conversations side by side in separate windows. Wireshark 4.0 makes them more powerful and easier to use. The Conversations and Endpoints dialogs have been a popular feature for a long time and are often the first place people look when investigating a problem. As of Wireshark 4.0, the default is for the detail and byte view to be next to each other, which makes it easier to take advantage of the real estate available on modern displays: Conversations and Endpoints That standard was set a long time ago when most monitors had a 4:3 aspect ratio and lower resolutions than they do these days. In past releases Wireshark followed a standard set by its predecessors and placed the packet list, packet detail, and byte view on top of each other, like so: You can now match bytes starting from the end of a PDU, dates and times can be specified as UTC, Unicode can be matched using code points, Default main window layout There are a bunch of other changes as well. You can use the modulo operator to match them like so: = 443 Suppose your company has all of its web servers running on a port that ends in 443: 443, 1443, 5443, 21443, etc. You can use the modulo (%) operator, which gives you the remainder of integer division. You can also do arithmetic – you can add, subtract, multiply, and divide. If any addresses don’t match, we have a winner, similar to “!=” in version 3.4 and earlier. If all addresses match, we have a winner. If none of these match, we have a winner, similar to “!=” in version 3.6 and later. If any of these match, we have a winner, similar to “=”. Wireshark 4.0 adds the following: ip.addr any_eq 10.100.100.1 In Wireshark 3.6 and later, if none of these match, we have a winner. In Wireshark 3.4 and earlier, if any of these don’t match, we have a winner. Wireshark also has “!=” (not equal), which was a bit confusing in past versions. You have been able to do the following comparison operators since Wireshark’s inception: ip.addr = 10.100.100.1 Will match the inner address, and ip.src = 10.1.2.3Īlong with layers, you can be much more specific about matching zero, one or more, or all fields in a particular packet. Will match the outer address, ip.src#2 = 10.1.2.3 For example, if we have a GRE packet with both outer and inner IPv4 layers, ip.src#1 = 10.1.2.3 To use the layer operator, just put a number sign and a layer number after a field. In order to reduce this ambiguity Wireshark 4.0 adds a layer operator, which lets you select a specific occurrence of a field. 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.
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