On Sun, Apr 25, 2010 at 7:56 PM, Dino Ciuffetti <di...@tuxweb.it> wrote:
Found the mail header modification that cause DKIM verification problem
my case from mails coming from gmail.com (and other) to my courier servers.
It's "Content-Type" header. Its value is not case protected by the DKIM
relaxed alghoritm specification at sign level, even if CT value should
trated as case insensitive.
Sam, since changing/fixing the DKIM canonicalization standard is not a
simple thing and will probably require a long time,
is it possibile / may have sense / would you have time and desire to write
a work around in courier to leave the CT value as it comes from the remote
smtp client if it is not broken (avoid changing ISO-8859-1 to iso-8859-1)?
If memory serves me right this problem crops up with Courier MLM
modifying a message when it is being redistributed. In that case,
shouldn't the solution be that CourierMLM resigns the message as the
origin of the distributed message? Other than that to my mind, you are
going to end up chasing a never ending list of exceptions where
something gets changed and DKIM breaks, and sticking plaster after
sticking plaster to keep it working.