[PATCH] lib-imap: imap-bodystructure: add test with empty header field

[Simon Ser]

On Tuesday, March 3, 2020 9:00 PM, Timo Sirainen <timo at sirainen.com> wrote:

> On 3. Mar 2020, at 20.38, Simon Ser contact at emersion.fr wrote:
>
> > This causes the body structure to be incorrect. The RFC says it's fine o
> > have empty header field values.
>
> The problem isn't empty header field. It's that the mail is missing Mime-Version header. If that doesn't exist, then the Content-* headers can be ignored. But because there are so many broken mails, Dovecot also allows it to be missing as long as there is Content-Type header. Your test mail has neither of these headers. It's arguable that Dovecot should parse Content-* headers regardless of other headers, but I don't think the current code is violating any RFCs.

Oh, sorry, I thought this caused by the empty header field.

The e-mail found in the wild doesn't have Mime-Version, so it would
probably be a good idea not to ignore Content-Transfer-Encoding indeed.