On Wed, Oct 8, 2025 at 10:51 AM Guy Harris <[email protected]> wrote:
> On Oct 8, 2025, at 10:33 AM, Francois via tcpdump-workers < > [email protected]> wrote: > > > On 08/10/2025 18:53, Guy Harris wrote: > > > >> OK, so does this finally make the Length field in the UDP header serve > a useful purpose, or was there a purpose for it *before* this that I didn't > know about? > > > > One example on network stacks: Linux, net/ipv4/udp.c and net/ipv6/udp.c: > length checks. > > But if the UDP header hadn't had a length field in the first place, and > the UDP payload always ran to the end of the (possibly-reassembled) IP > datagram, there wouldn't be a length field to check. RFC9868 basically had a couple of guesses as to why there is a separate length field, but basically says the reasons are lost to time. Bill _______________________________________________ tcpdump-workers mailing list -- [email protected] To unsubscribe send an email to [email protected] %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s
