V10/cmd/upas/questions

how much time would it take to do this?

I can usually get the software up in about ten minutes (FLW).  The
rewrite and routing files take an hour or two of deep thought
and easy work.  I am willing to work with someone to accomplish this.

does upas run on any bsd vax system already, or would
we have to port it?

It used to run on arpa, a 4.3 bsd machine.  It hasn't been run on
one for over a year that I know of.  On the other hand, it Just Works
on suns, MIPS, and SGI machines.

does it run on any bsd-based systems where /bin/sh
is the bourne shell (i.e. doesn't put background
jobs into their own pgrp, meaning that all a
user's background jobs may get signal 1 when s/he logs
out)?

I'm not sure this is a factor.  In any case, I always use the
Bourne shell on all upas systems that I manage.

what programs need to be replaced?  mail, rmail, Mail?

The crucial program is /bin/rmail (linked to) /usr/lib/upas/send.  This
is the transfer agent.  You can install our minimalist V7 mail reader
as /bin/mail (as on many machines), use mailx supported by someone
else in our center, or (I guess) use any mail reading program that
delivers mail to /bin/rmail.

does it create mail files that can be read by
/usr/ucb/Mail (the From lines must be preceded by
blanks and the date/time portion has to be one of
a few specific formats)?

I don't know.  Feel free to test it on alice.

does it collapse multiple remote from xxx lines
into a single address so that users can type 'r'
in their favorite mail-reading program (mail, Mail, mailtool, mh,
emacs) and have the reply go to the right place?

This is a sticky one.  It derives the "From " address from the
envelope or an RFC-specified series of header lines.  You would definitely
want to check it out before taking the plunge.

does it support hashed aliases?  if not,
i think it might be too slow on allegra or andante.

Aliases are looked up by a filter called `translate'.  The upas
version is dirt-simple, and gives a performance hit on machines
like 750s.  You can easily roll your own (look(1) is a big win) to do
what you want the way you want it.

what if the alias file is in the process of being written
when mail comes in?

depends on your translate program and update process.

might some get bounced?

This does happen on rare occassions on our machines.

how secure is it?  can anyone run programs as another user
or as root or write to another user's files?

upas was written because sendmail was obviously insecure.  It tends
to be small and modular, with easily-understandable components.  The smtp
stuff in particular is small and has been revetted many times.  I wouldn't
bet my daughter on it, but I probably would bet next week's salary.
The smtp daemons run as `uucp'.  `Send' runs as root for the usual
reasons.  It takes a lot of care before writing into a `mailbox.'

can we have user-maintained mailing lists that won't
compromise security?

Obviously they could break mailing by rerouting addresses, but I can't think
of a way they could break into the system or overwrite an inappropriate
file.

will upas let us mail to novax!user to send mail over
uucp to atlanta, yet let us mail to user@novax to
send mail to users on our major sun?

Yes.  This is easily arranged with the rewrite rules.  The rewrite rules
are a series of regular expressions and a few verbs, and a shell scripts
to do the actual delivery.

paul reported problems in which mail to
paul@argo.tempo.nj.att.com get converted to argo!paul
and then went to some unrelated system.
has this problem been fixed?

This is the result of policy decisions dealing with mapping domain and
uucp name spaces.  Our rewrite rules implement our policy.  I am not happy
with the current arrangement, but haven't been able to figure out how to
do what we want without breaking other stuff.  I continue to ponder
possible solutions.

can upas send mail to user@[aa.bb.cc.dd], i.e. a dotted
internet address?  that's the address symbolics systems present to us.

Again, this can be handled with rewrite rules.  We have implemented some
of this form with no trouble.