🚀 go-pugleaf

There's a bit of an "oooh, nasty" in KA9Q's mailkill handling.  The
variable 'bad_sender' in smtpserv.c is global (only one copy for the
system), where it should be locally allocated in sptpserv() (one per
receive process).  This means that, when you have two receives going in
parallel, a rejection on one will also cause the other, valid, stream to
perform a mail rejection, if it is itself inbetween the "MAIL FROM" and
"DATA" stages, inclusive, of the protocol.  

I'd long wondered how that NeedSender 503 could be triggered; now I know
- fortunately only on a message I'd forwarded to myself.  Note that the
rejection is silent; it is *not* logged on the screen or in mail.log.

The same also applies to the variable 'fail', which is used to do the
"deliver default" and other alias thangs.  In this case the variable is
used to communicate between smtpserv() and expandalias(), so a little
more work will be needed to pass back the results.  Expandalias() is
also called from mailuser() and unfortunately I haven't time right now
to track through all the implications of this.  Note that there is
another independent variable also called fail in mailit().

P.S. Many returns of last week, John.  Did you get that nice new shiny
hardware debugger ? :-)

Nick Leverton