On Sep 13, 2016, at 10:03 PM, Yang Luo <hslu...@gmail.com> wrote: > But the problem is, libpcap (which is used by Npcap) only supports the value > 23 in the BPF filter code.
This is a problem in more ways than one. For example, if you're running on FreeBSD, and are reading a pcap or pcapng file from NetBSD, and it has loopback packets, a filter checking for IPv6 packets won't work, because it'll be looking for the FreeBSD AF_INET6 (28), but IPv6 packets will have NetBSD's AF_INET6 (24). So, when reading a capture file, the filter should check for *all* of the possible AF_INET6 values, because there's no way to determine, from the file, which AF_INET6 value was used. When doing a live capture, it should, if possible, just use whatever the capture mechanism provides, to avoid doing other checks. I'll fix this up; for now, just keep using 24 - it's not as if any code that wants to read an AF_NULL pcap file can rely on its OS's AF_INET6 being the packet type value *anyway*, it has to check for all platform values (which both tcpdump and Wireshark do). ___________________________________________________________________________ Sent via: Wireshark-dev mailing list <wireshark-dev@wireshark.org> Archives: https://www.wireshark.org/lists/wireshark-dev Unsubscribe: https://www.wireshark.org/mailman/options/wireshark-dev mailto:wireshark-dev-requ...@wireshark.org?subject=unsubscribe
