them in "print-sll.c" - as a cooked-mode capture may be reading from
non-Ethernet, non-802.x devices, it may well see some
ETH_P_/LINUX_SLL_P_ types that don't mean "this is an 802.2 LLC frame".
We currently assume that the ETH_P_ values won't change in the kernel,
so we don't have to explicitly map them.
In various link-layer packet printers, if we don't handle the next layer
up of packet type, and are printing the link-layer header, use the
correct pointer to that header (i.e., if we've stepped "p" past the
link-layer header, don't use "p", use a pointer to the beginning of the
packet), and use the correct length (i.e., if we've subtracted the
length of the link-layer header, add it back in, so that we always print
the full packet length).
live captures with a "cooked" (SOCK_DGRAM) rather than a "raw"
(SOCK_RAW) PF_PACKET socket; it includes a bunch of the fields from the
"struct sockaddr_ll" you get in a "recvfrom()", including the Ethernet
protocol field.