On Thu, Jun 05, 2014 at 05:59:30PM +0200, Arnt Gulbrandsen wrote:
> What's the problem with the canonical representation exactly as it appears
> on the wire in SMTP? What's the problem with using the same representation
> for domains as for localparts?
I can't read or write Chinese, Japanese, Korean, Tamil, ... but
need to be able to set policy for such domain names from (e.g. white-list
them, ...). I can read/write a-labels.
> Maybe SMTP and DNS should have used the same wire representation. It's too
> late to change that now, though.
Indeed domain names in EAI SMTP (and in message headers) should
have been mandated to be a-labels with display conversion to UTF-8
left to MUAs. Since the EAI RFCs are in error, if Postfix implements
EAI, it needs to do its best to correct the errors.
DKIM signature domains need to be a-labels. When Postfix generates
header addresses, those should be a-labels. Obviously if header
addresses already contain unicode, and Postfix is not rewriting
the header, it should leave unicode domains alone, but otherwise
Postfix should never introduce them, and should pass only a-label
domain forms to table drivers (when passing addresses or domains
rather than free-form header text as with header_checks).
--
Viktor.
