smtp-server, and toplevel domain verification..

[Matti Aarnio <mea@nic.funet.fi>]

Hello,

	I saw recently somebody sending mail thru smtp-server with
	following (quite mad) address:

		<plspgme!!!!@fsdfs.dfsfs>

	This prompted me to go thru smtpserver's  rfc-821 scanner,
	and alter the treatment of the local part ("plspgme!!!!")
	to consider non-quoted bangs, and percents as specials.

	Now the server treas this address as:

mail from:<plspgme!!!!@fsdfs.dfsfs>
501-5.5.2          ^
501 5.5.2 Path data: After a '!', a non alphanumeric element

	Should similar scanners be added also into  "sendmail"
	program for analysis of envelope addresses ?


	This did also prompt me to think of adding a quick
	first line defence of verifying that the address has
	valid top-level domain at the extreme right, or that
	it is one of the local system names.

	The question is, does this make sense ?  Does it help ?
	Should I implement that test even without policytest
	facility being active ?

/Matti Aarnio <mea@nic.funet.fi>