On Tue, May 25, 2010 at 11:36 AM, Todd Lyons <tlyons_at_ivenue.com> wrote:
>>>
>>> So _something_ is changing that Sender header after the signature is
>>> generated. I have not been able to isolate where the change is
>> Good sleuth work. It would be interesting to know which piece of software is making that change, especially post-signing. This would be useful for our README.
>
> I'll create the test list again, turn on KeepTemporaryFiles and see if
> I can spot something.
Did some debugging. Sendmail must be changing it. This is the
canonicalized Sender header that opendkim is signing:
sender:oclug-test-bounces_at_mailman.oclug.org
And this is the Sender header that is in the received email:
Sender: oclug-test-bounces_at_penguin.oclug.org
If it's useful:
# rpm -q sendmail
sendmail-8.13.8-8.el5
... on CentOS 5.5.
Here is the technical detail of the Mailman hostname setting that is
uses to create that Sender header:
======= BEGIN
host_name (general): Host name this list prefers for email.
The "host_name" is the preferred name for email to mailman-related
addresses on this host, and generally should be the mail host's
exchanger address, if any. This setting can be useful for selecting
among alternative names of a host that has multiple addresses.
======= END
I have it set to "mailman.oclug.org", whereas the machine hostname is
penguin.oclug.org (both are in the local-host-names w class file). So
for some reason, sendmail is rewriting the Sender header that Mailman
created (and signed) to the machine hostname. I do not have any kind
of Masquerading or genericstable configured, so I am unsure why
sendmail is doing that. To be more exact, I don't have any deep or
meaningful experience with the Sender header specifically, so I am
unsure if this is even expected behavior.
I have attached the canonicalized headers from the KeepTempFiles
setting, if it's useful.
--
Regards... Todd
I seek the truth...it is only persistence in self-delusion and
ignorance that does harm. -- Marcus Aurealius
Received on Tue May 25 2010 - 19:13:19 PST