Certificate renewal can be done only one one CA as the certificates need
to be shared amongst them. certmonger has been trained to communicate
directly with dogtag to perform the renewals. The initial CA installation
is the defacto certificate renewal master.
A copy of the certificate is stored in the IPA LDAP tree in
cn=ca_renewal,cn=ipa,cn=etc,$SUFFIX, the rdn being the nickname of the
certificate, when a certificate is renewed. Only the most current
certificate is stored. It is valid to have no certificates there, it means
that no renewals have taken place.
The clones are configured with a new certmonger CA type that polls this
location in the IPA tree looking for an updated certificate. If one is
not found then certmonger is put into the CA_WORKING state and will poll
every 8 hours until an updated certificate is available.
The RA agent certificate, ipaCert in /etc/httpd/alias, is a special case.
When this certificate is updated we also need to update its entry in
the dogtag tree, adding the updated certificate and telling dogtag which
certificate to use. This is the certificate that lets IPA issue
certificates.
On upgrades we check to see if the certificate tracking is already in
place. If not then we need to determine if this is the master that will
do the renewals or not. This decision is made based on whether it was
the first master installed. It is concievable that this master is no
longer available meaning that none are actually tracking renewal. We
will need to document this.
https://fedorahosted.org/freeipa/ticket/2803
I couldn't put the dogtag rules into the spec file until we required
dogtag as a component. If it wasn't pre-loaded them the rules loading
would fail because types would be missing.
This policy should really be provided by dogtag. We don't want
to grant read/write access to everything dogtag can handle so we
change the context to cert_t instead. But we have to let dogtag
read/write that too hence this policy.
To top it off we can't load this policy unless dogtag is also loaded
so we insert it in the IPA installer