Re: [exim] DKIM signing options - specially list of headers

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Author: Mike Brudenell
Date:  
To: Exim Users
Subject: Re: [exim] DKIM signing options - specially list of headers
Hi, Sebastian -

You didn't tell us the version of Exim you're running so I can't give you
the exact chapter/section names, but if you look in the *Specification* for
the chapter on DKIM, in the section called something like *Signing outgoing
messages* you'll find the description of dkim_sign_headers.

However I'd have thought that the defulat set of headers should be OK as
the *Specification* does explain:

When unspecified, the header names listed in RFC4871 will be used, whether
or not each header is present in the message. The default list is available
for the expansion in the macro "_DKIM_SIGN_HEADERS".


I
n particular that RFC's *Recommended Signature Content
<https://tools.ietf.org/html/rfc4871#section-5.5>* explicitly recommends
DKIM-signing various List-* headers. I'd be tempted to point this out to
the people complaining and suggests they look elsewhere for the cause of
their problems.

Cheers,
Mike B-)

On Tue, 31 Jul 2018 at 09:51, Sebastian Arcus via Exim-users <
exim-users@???> wrote:

> I post messages from time to time to Spamassassin mailing list, and
> several members have been complaining about my DKIM setup - they say
> they can't receive my emails because of it. Specifically, the complaint
> is that my Exim signs the List-* headers. Now I can't really figure this
> one out. There don't seem to be any fine-grained DKIM signing options in
> Exim. My messages to the list arrive looking like this:
>
>
> DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed;
>         d=open-t.co.uk; s=20170820;
> h=Content-Transfer-Encoding:Content-Type:

>
> MIME-Version:Date:Message-ID:Subject:From:To:Sender:Reply-To:Cc:Content-ID:
>
> Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc
>
> :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:
>         List-Subscribe:List-Post:List-Owner:List-Archive;
>         bh=d0g337Alhc+FWBBtMm7w/Hn67G4jbr0RsFSBcWDK2fc=;
> b=Nhn9sI6K1G8+vOfCsguSXGA8+6

>
> 0Aap3I3NcIZ3F21rrGivbp2eS+Gz42GAn/NvYrrz9RkYL5/PIqr5a6v8QhEio6KGSO1d/RIZVQMaf
>
> V7qqFyvU8GB3MAYavZa+MsLAOmVgxSk3rSAbE+Bk2RER08QGjwLKxEOotKSy6vXzF25s=;
>
>
> (sorry for the odd line breaks - it looks ok in the actual header of the
> email)
>
> My question is, the list of headers -
> "h=Content-Transfer-Encoding:Content-Type:MIME-Version ...." - where
> does that get generated? Is it on my Exim box - or further down the
> line? Also, why is that preventing users of the mailing list from
> receiving my messages?
>
> My setup is fairly simple - Thunderbird -> Exim -> and then direct
> sending to the recipient server.
>
> Any hints or pointers to reading material would be much appreciated
>
> --
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> ## Exim details at http://www.exim.org/
> ## Please use the Wiki with this list - http://wiki.exim.org/
>



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