My fix to RARP ifaddr initialization

[Steve Miller]

[Sun-Nets folks, I don't think you saw this fix on Sun-Nets.  I'm Cc'ing
you largely to solicit comments on the second part of this message.  SDM ]

Craig Leres pointed out to me that my fix for if_ether.c (the one that
zeroes out the sockaddr before using it for an interface address) is
wrong.  Somehow or another, in the diff I sent out, the following line
fell in the bit bucket:

	sin = (struct sockaddr_in *)&temp;

It goes right after the line with the bzero call, and before the line with
the sin_family assignment.  Oops, and sorry.

On a similar topic, it seems to me (and, apparently, to others) that doing
a broadcast ICMP netmask request is antisocial in today's environment.  I
watched a NeXT machine touch off a brief, 15-machine broadcast storm the
other night by sending out such a request.  The broadcast and replies were
correctly handled -- but, as is the case with more usual broadcast storms,
all 15 machines tried to respond at the same time, and probably jammed
things up a bit.

Fifteen machines doesn't worry me so much...  but every 4.3BSD-derived box
on the CS Department Ethernet responded.  That includes our 4.3BSD VAXen,
our DECstations (I think), and the one SunOS 4.0.1 Sun-4 on that cable.
If we were running 4.0.1 on all sixty or so Suns on that cable, at least
75 machines would have been jabbering at one another, and the noise would
be deafening.

Am I the only one who thinks that sending netmask replies should be #ifdef
GATEWAY or should otherwise come with a knob?  Similarly, for those
vendors who want to send such requests regardless of the current
environment, shouldn't the request code be equipped with a similar knob,
so if sending such requests hurts too badly, we can stop?

Does anyone have an up-to-date Hosts Requirements RFC draft they can check
for guidance?  Am I being unnecessarily alarmist?

	-Steve

Spoken: Steve Miller    Domain: steve at mimsy.umd.edu    UUCP: uunet!mimsy!steve
Phone: +1-301-454-1808  USPS: UMIACS, Univ. of Maryland, College Park, MD 20742