Adjust interaction of CREATEROLE with role properties.

Previously, a CREATEROLE user without SUPERUSER could not alter
REPLICATION users in any way, and could not set the BYPASSRLS
attribute. However, they could manipulate the CREATEDB property
even if they themselves did not possess it.

With this change, a CREATEROLE user without SUPERUSER can set or
clear the REPLICATION, BYPASSRLS, or CREATEDB property on a new
role or a role that they have rights to manage if and only if
that property is set for their own role.

This implements the standard idea that you can't give permissions
you don't have (but you can give the ones you do have). We might
in the future want to provide more powerful ways to constrain
what a CREATEROLE user can do - for example, to limit whether
CONNECTION LIMIT can be set or the values to which it can be set -
but that is left as future work.

Patch by me, reviewed by Nathan Bossart, Tushar Ahuja, and Neha
Sharma.

Discussion: http://postgr.es/m/CA+TgmobX=LHg_J5aT=0pi9gJy=JdtrUVGAu0zhr-i5v5nNbJDg@mail.gmail.com

1 files changed, 1 insertions, 0 deletions

diff --git a/src/include/commands/dbcommands.h b/src/include/commands/dbcommands.h
index 9b8818315a..5fbc3ca752 100644
--- a/src/include/commands/dbcommands.h
+++ b/src/include/commands/dbcommands.h
@@ -30,6 +30,7 @@ extern ObjectAddress AlterDatabaseOwner(const char *dbname, Oid newOwnerId);
 
 extern Oid	get_database_oid(const char *dbname, bool missing_ok);
 extern char *get_database_name(Oid dbid);
+extern bool have_createdb_privilege(void);
 
 extern void check_encoding_locale_matches(int encoding, const char *collate, const char *ctype);