Backport: 5x -> 2x ARH checking and code structure

[dodmi]

Hi,

I followed your changes to separate the code for "cached results" and "ARH checking" to different modules.
Additionally, I backported the change to not check the AUID anymore, after reading the RFC.

But, I don't understand your changes to setting SDID and AUID for ARHs:
Instead of always complementing SDID and AUID, it's only done, if the ARH result replaces DKIM verification.

• Why did you move the code to do the complementation only in this case?
• As AUID isn't checked anymore, why is it complemented with an existing SDID, anyway?
• If neither AUID nor SDID is given, SDID stays undefined
• If there's no SDID and ARH result doesn't replace the DKIM verification, SDID stays undefined
• But the SUCCESS string contains a field for the SDID

At the moment, my code follows the old behavior to complement SDID/AUID and I've copied your check method, which will do the same. Depending on your reply, I'll remove the code in one place.

As SDID may be undefined in the case, that neither SDID nor AUID is defined, in any case, we'll probably need to change the SUCCESS message. (I didn't have any real world mail and just realized this, checking your new test cases)

Other topic: I didn't backport the changes to the libunbound files. I couldn't get it working, trying to backport the changes.

And I hope, I didn't miss anything

[dodmi]

Sorry, wrong branch...