This patch adds a Clear method to the domaininfo database, which removes
information for the given domain.
This can be used to manually make the server forget about a domain, in
case there are operational reasons to do so.
Today, this is done via chasquid-util (which removes the backing file),
but that is hacky, and this is part of replacing it with a cleaner
implementation.
This patch changes several internal packages to receive and pass tracing
annotations, making use of the new tracing library, so we can have
better debugging information.
This patch makes chasquid reload domaininfo periodically, so it notices
any external changes made to it.
It is in line with what we do for aliases and authentication already,
and makes it possible for external removals an additions to the
domaininfo database to be picked up without a restart.
We have many places in our tests where we create temporary directories,
which we later remove (most of the time). We have at least 3 helpers to
do this, and various places where it's done ad-hoc (and the cleanup is
not always present).
To try to reduce the clutter, and make the tests more uniform and
readable, this patch introduces two helpers in a new "testutil" package:
one for creating and one for removing temporary directories.
These new functions are safer, better tested, and make the tests more
consistent. All the tests are updated to use them.
This patch introduces a new "domaininfo" package, which implements a
database with information about domains. In particular, it tracks
incoming and outgoing security levels.
That information is used in incoming and outgoing SMTP to prevent
downgrades.
