In article <79907$4547c1ff$c02a7def$2145@news1.tudelft.nl> Kees
Theunissen <theuniss@rijnh.nl> writes:
>Bill Seligman wrote:
>> I've been trying to get DomainKeys to work on my mail server. I know
>> this is not the DKIM newsgroup, but there's one issue I'd like to know
>> about before I dismiss it as the cause of the problem.
>>
>> My mail server breaks up long headers with "\r\t" characters. Here's an
>> example of what I mean:
>>
>> DomainKey-Signature: a=rsa-sha1; s=mail; d=nevis.columbia.edu; c=simple;
>> q=dns;
>> b=jXOJ3HiGQX+GP/t0eaAkXa0tHj4jZbs1jlI1xK9F4dhzHhHfNqa9PF7MvWf+kP0j K
>> xALUc16S1FBwbSehokU4w==
>>
>> As you can see, the "b=" field (containing the DomainKey signature
>> information) has been broken into two lines.
>
>The format of mail headers (and the folding and unfolding of long
>headers) is defined in rfc2822. Normaly can folding only be done
>at a place in the header with existing whitespace.
>
>But see the definition of the DomainKey-Signature header at
>http://www.ietf.org/internet-drafts/...ys-base-06.txt
>
> INTERNET DRAFT Mark Delany
> Title: draft-delany-domainkeys-base-06.txt Yahoo! Inc
[snip]

>So there is nothing wrong with your header as far as I can see.

I would agree - but does the software doing the folding really "know"
that? Unless it's the one inserting the header (i.e. it is actually
folded to start with), this seems unlikely, in which case the folding
sofware is broken.

Anyway, sendmail doesn't fold headers (unless they would exceed the SMTP
line length limit of ~ 1000 chars) AFAIK - in particular not headers
that it doesn't even "process", and DomainKey-Signature would definitely
be in that category.

--Per Hedeland
per@hedeland.org