[NFS-Ganesha-Devel] Understanding ganesha's idmapping behavior for specific principals

Hi team, Looking at the Ganesha nfs idmapper code (at https://github.com/nfs-ganesha/nfs-ganesha/blob/next/src/idmapper/idmappe...), I wish to understand the rationale behind resolving principals of the form "nfs/*", "host/*" and "root/*" to the "root" user. I could not find any mention of it in the NFS protocol RFCs. Is there a specific use-case that this code enables? Thanks, Dipit