Re: [ietf-smtp] Valid RFC5322 address

[Hector Santos <[e-mail]>]

Thanks Ned and Claus:

On 5/3/2020 11:11 AM, Claus Assmann wrote:
> On Sun, May 03, 2020, Hector Santos wrote:
>> It appears to be accepted by various servers, including my own.
>
> Well, most mail servers accept all kind of garbage ("be liberal ... ").
>
> Mine doesn't:
> Mail from:<github.agent:.github-hookshot/[e-mail]>
> 501 5.1.7 Bad sender's mailbox address syntax.

The icloud.com SMTP server accepted it. How I saw the issue was with 
Apple's web-based icloud.com mail reader/viewer (MUA).   It showed a 
blank From: field when first reading it. But after viewing a previous 
email, i.e. Apple News, it now used Apple's From address as a filler 
for the notification email from field display. The bugs were reported 
to Apple.

> Just quote it and you're ok:
> <"github.agent:.github-hookshot/7431eee"@winserver.com>

Ok. I am probably to change it so isn't a problem with MUAs as well -- 
be "conservative" on sending out. :-)

>> So I need to know if the address is valid. Its hard to decipher whether it
>> is or not from the RFC5322/RFC5321 BNF. It seems to read the ':' and '/'
>> characters are valid.
>
> Where do you see an unquoted ':' as valid in "Local-part"?  ':' is
> used to separate "At-Domain" parts.

I guess I was reading multiple things between RFC5322 and RFC5321. 
Jumped around a lot.

As Ned showed, I see now RFC5222 better defines the local-part. But 
with RFC5321, it wasn't quite clear.  It seems to stop with only one 
occurrence of atext, no BNF for it and no reference to atext being 
defined in RFC5322.

I suppose this might be another clarification issue for RFC5321bis.

Thanks

-- 
HLS