complete for some reason, we defer it for a bit and then try again. This
gets ping down to 0% packet loss.
Of course, ping _should_ have been at 0% packet loss anyway, and that's the
next thing to deal with.
worked out by observing RISC iX's behaviour, so it may be technically
wrong. The only implementations of IP-over-Econet for which I've got
sources don't support broadcasts.
Tested using broadcast ping from RISC iX to NetBSD, and using rwhod.
Use m_copydata() to preserve the Econet header, so we don't depend on
notionally-unused areas of an mbuf remaining untouched.
Check that ARP-over-Econet requests are exactly eight bytes long.
Use m_pullup() before trusting mtod().
Between them, these make reception of unicast ARP responses work properly.
protocols, and lacking any timeouts, but it basically works, doing four-way
handshakes in both directions and incoming Machine Peek operations.
Oh, and Econet is Acorn's ancient, proprietary 500kbit/s networking
technology.