[ietf-dkim] DKIM vs. MIME

[Alessandro Vesely]

On 25/Apr/10 08:04, ned+dkim at mauve.mrochek.com wrote:
>>> field, DKIM is doing something "wrong".  In any case, it was suggested on that list that "relaxed" header canonicalization be adjusted to accommodate this.

I'd rather define new canonicalization algorithms than tamper with 
existing ones.

>> [...] but the addresses in To:, From:, Cc;, and so forth certainly are

> [...] But since new media types are defined all the time, and old ones are revised, to say nothing of the types people just make up and never register. As such, you cannot possibly code something that gets case normalization right in general. So yes, it's hopeless.

An alternative would be to err on the other side: a "mellowed" 
canonicalization, that respects only the fields and entities whose 
meaning and encoding is well known and stable, so as to allow some 
kind of forgeries rather than accidental breaking.