sdap_idmap_domain_has_algorithmic_mapping: add domain name argument When libss_idmap was only used to algorithmically map a SID to a POSIX ID a domain SID was strictly necessary and the only information needed to find a domain. With the introduction of external mappings there are cases where a domain SID is not available. Currently we relied on the fact that external mapping was always used as a default if not specific information about the domain was found. The lead to extra CPU cycles and potentially confusing debug messages. Adding the domain name as a search parameter will avoid this.

Add sdap_idmap_domain_has_algorithmic_mapping() This patch implements a wrapper for sss_idmap_domain_has_algorithmic_mapping() for the sdap ID mapping. Fixes https://fedorahosted.org/sssd/ticket/1960

Allow different methods to find new domains for idmapping Currently the range management code is in the generic LDAP provider and can be used by the LDAP and AD provider. New ranges are allocated with the help of a hash value of the domain SID. If the IPA provider cannot find a range for a given domain it cannot allocate a new range on its own but has to look up the idrange objects on the FreeIPA server and use them accordingly. To allow the LDAP, AD and IPA provider to use as much common code as possible a plugin interface, similar to the one used to find the DNS site, to find a missing range would be useful. The default plugin will be used by the LDAP and the AD provider and the IPA provider will implement a plugin to read the data from the server. Fixes https://fedorahosted.org/sssd/ticket/1961

libsss_idmap: function to calculate range Calculation of range for domains is moved from sdap_idmap code to sss_idmap code. Some refactoring have been done to allow this move. https://fedorahosted.org/sssd/ticket/1844

LDAP: Add helper function to map IDs This function will also auto-create a new ID map if the domain has not been seen previously.

LDAP: Add routine to extract domain SID from an object SID Also makes the domain prefix macros from sss_idmap public.

LDAP: Add helper routines for ID-mapping