Re: Return codes, was Updated draft for "SMTP Response for Detected Spam"

--On Thursday, March 31, 2022 10:45 -0700 Ned Freed
<[email protected]> wrote:

> In our world at least, use of previously undefined status
> requires an extension. This is because a certain library for a
> certain language whose name begins with "J" throws an
> exception when it sees a status code it doesn't recognize.

Hmm.  Should I assume that it has been pointed out to the
authors of said library that they are in violation of a rather
specific provision of RFC 5321 and that they are not listening?

> Of course you can modify the app to catch and ignore the
> exception, but customrs are curiously reluctant to do that.
> 
> Maybe this implies that a
> ACCEPTANYSYNTACTICALLYVALIDSTATUSCODE extension would be
> useful. Or not.

Not really an extension because of the paragraph of Section 4.2
of RFC 5321 that starts

	"An SMTP client MUST determine its actions only by the
	reply code,..."

if that paragraph is not sufficiently clear that clients are not
allowed to throw exceptions (or otherwise have fits) when they
receive a reply code of three digits starting with 2, 3, 4, or
5, this would be a good time to suggest improvements.  
	
And, for this particular case, perhaps an
IAMINTERESTEDINWHATTHEMDATHINKSOFTHISMESSAGE extension, which
would generalize from MAYBESPAM and include "maybe highly
focused phishing attack" and other possible conclusions from
analysis on the delivery system, would be useful.  Or not.


  john