Re: DKIM verification failures due to message body change when using HTML email

From: SM <sm_at_resistor.net>
Date: Mon, 03 Dec 2012 10:20:23 -0800

At 09:11 03-12-2012, Quanah Gibson-Mount wrote:
>I've gotten a few reports of DKIM verification failures (DKIM
>verification in this case is being done by amavis, OpenDKIM is doing
>the signing). The following forum thread details the issue, and
>includes three example messages (2 failures, one success).
>
><https://www.zimbra.com/forums/administrators/59532-dkim-signature-do-not-validate-when-using-smtp-send-mail.html>
>
>The two failures are both HTML based emails, and the once success is
>plain text. I found this thread:
>
><http://forums.phplist.com/viewtopic.php?f=16&t=17520&start=15#p91725>
>and
>
><http://forums.phplist.com/viewtopic.php?f=16&t=17520&start=15#p92317>
>
>where it looks like someone found an issue with mail using HTML that
>is signed by OpenDKIM. Is this a bug on the OpenDKIM side or in the
>Amavis verification side of things?

I did not look at the messages as the forums require
registration. At a guess the problem is not with HTML; it may be
some modification in transit due to encoding.

Regards,
-sm
Received on Mon Dec 03 2012 - 18:39:14 PST