[Pki-devel] Keytab for talking to PKI CA from IPA

When setting up replication, it should not be necessary to cache any passwords, anywhere, until the replication agreemsnts are set up, and then, all caching should be using known secure mechanisms. The two main repositories we care about are the Directory Server instances managed by IPA and the Certificate Authority. Currently, these are not in the same Dir Srv isntance (although they could be) due to the fact that we expect to replicate them seperately. Specifically, we expect to have more IPA instances than CA instances, and we will not have a CA instance without a co-located IPA instance. During normal operations, the IPA instance should not need to talk to the directory server instance of the CA. All communication between IPA and the CA should happen via the HTTPS secured via Certificates issued by the CA. Once the replication process starts, the file generated by ipa-prepare replicate should not need an passwords. Instead, when the replicated server is installed, the user performing the install should get a ticket as an administrative user. All authentication for the replication should be based on that ticket. The very first step is to install an new Directory server for IPA. For this, the replication process can generate a single use password and use it as the Directory server password for the local instance. Next, the ticket for the adminiustrative user should be used to download a keytab for the Directory Server to use when communicating back to the original IPA directory server.With these keytab in place, the replicated IPA DS should be able to talk to the original IPA DS and establish the replication agreement. At this point, the single use password should be disabled. Once the IPA Directory server has been replicated, we can either use the original keytab or download a second keytab to establish a replication agreement between the replicated CA directory server and the original CA directory server. The process would look the same as setting up the keytab for the IPA directory server. Why don't we do this now?