For bidirectional trust if we have AD administrator credentials, we
should be using them with Kerberos authentication. If we don't have
AD administrator credentials, we should be using
HTTP/ipa.master@IPA.REALM credentials. This means we should ask
formatting 'creds' object in Kerberos style.
For one-way trust we'll be fetching trust topology as TDO object,
authenticating with pre-created Kerberos credentials cache, so in all
cases we do use Kerberos authentication to talk to Active Directory
domain controllers over cross-forest trust link.
Part of trust refactoring series.
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1250190
Fixes: https://fedorahosted.org/freeipa/ticket/5182
Reviewed-By: Tomas Babej <tbabej@redhat.com>
Alexander Bokovoy
1255dbf2fd