Re: [Extra] Email header / address parsing

[John Levine <[e-mail]>]

In article <[e-mail]> you write:
>Hi,
>
>I was reading https://www.usenix.org/system/files/sec20-chen-jianjun.pdf and started wondering if IMAP should be
>handling some of this better. Especially for generating ENVELOPE. We could even still have time to add
>recommendations to IMAP4rev2?
>
>For example:
> - From: [e-mail] <[e-mail]>
> - From: <[e-mail], <[e-mail]>

But the former is completely valid and occasionally useful, and the
latter is a syntax error. Don't we already have a "don't do that" rule
for invalid syntax?

>2a) Space preceding the first header name

That's a continuation line.

>2b) Space after From header: Again

Not sure what you mean but that's probably valid.

>2c) Folding space before ":"

Not valid but I don't think I've ever seen it.

Over in DMARC land people have been arguing for years about what to do
about misleading display names, and getting nowhere. 

While I certainly believe that it's possible to do spam filtering
looking for patterns that are likely to be phishes, I really don't
think that the IMAP address parser is the place to do it.

R's,
John