Couldn't this be handled by having a new permission on FUNCTIONs
("CALL"?) to distinguish EXECUTE?This would have to be made backwards-compatible, possibly by automatically granting CALL ON ALL FUNCTIONS to public at schema create time and/or PG upgrade time, which the schema owner could then REVOKE, or by requiring CALL permission only functions marked PRIVATE. Because initially a schema has no functions, the owner can revoke this grant to public before creating any functions, thus there would be no race contition. A race condition could be made less likely still by having CALL not imply EXECUTE (users would have to have both to successfully call a given function). I would agree that a PRIVATE keyword would be a syntactically convenient way to say that in its absence then public gets granted CALL on the given function. But IMO it shouldn't be necessary, and either way permissions machinery should be involved. What do other SQL databases do? Does any have a PRIVATE keyword for FUNCTIONs? Using permissions has the net effect of making visibility more fine-grained. Regarding \df, I'm not sure that hiding function names one cannot call is worthwhile, but if it were, then there are several options depending on whether confidentiality of function names is to be a security feature: RLS on the pg_catalog.pg_proc table (provides confidentiality), or having a system view on it or filtering in psql (no real confidentiality). All that said, being able to have PRIVATE schemas, tables, views, functions, FDWs, variables, maybe even roles, is definitly appealing, mainly for code organization reasons. I didn't understand how PRIVATE would help reduce the need for SECURITY DEFINER. Can you explain? Nico --
