v1-0003-Give-role-owners-control-over-owned-roles.patch

From 84206411750465665ac2076827c39c52f79ebbe6 Mon Sep 17 00:00:00 2001
From: Mark Dilger <mark.dilger@enterprisedb.com>
Date: Wed, 20 Oct 2021 08:52:25 -0700
Subject: [PATCH v1 3/4] Give role owners control over owned roles

Create a role ownership hierarchy.  The previous commit added owners
to roles.  This goes further, making role ownership transitive.  If
role A owns role B, and role B owns role C, then role A can act as
the owner of role C.  Also, roles A and B can perform any action on
objects belonging to role C that role C could itself perform.

This is a preparatory patch for changing how CREATEROLE works.
---
 src/backend/catalog/aclchk.c                  | 68 ++++++++++++++++---
 src/backend/catalog/objectaddress.c           | 22 +-----
 src/backend/commands/user.c                   | 16 +++--
 src/backend/utils/adt/acl.c                   |  4 ++
 src/include/utils/acl.h                       |  1 +
 .../expected/dummy_seclabel.out               | 12 ++--
 .../dummy_seclabel/sql/dummy_seclabel.sql     | 12 +++-
 src/test/regress/expected/create_role.out     | 21 ++----
 src/test/regress/sql/create_role.sql          | 11 ++-
 9 files changed, 102 insertions(+), 65 deletions(-)

diff --git a/src/backend/catalog/aclchk.c b/src/backend/catalog/aclchk.c
index 89792b154e..f24b664970 100644
--- a/src/backend/catalog/aclchk.c
+++ b/src/backend/catalog/aclchk.c
@@ -3418,6 +3418,9 @@ aclcheck_error(AclResult aclerr, ObjectType objtype,
 					case OBJECT_VIEW:
 						msg = gettext_noop("permission denied for view %s");
 						break;
+					case OBJECT_ROLE:
+						msg = gettext_noop("permission denied for role %s");
+						break;
 						/* these currently aren't used */
 					case OBJECT_ACCESS_METHOD:
 					case OBJECT_AMOP:
@@ -3428,7 +3431,6 @@ aclcheck_error(AclResult aclerr, ObjectType objtype,
 					case OBJECT_DEFACL:
 					case OBJECT_DOMCONSTRAINT:
 					case OBJECT_PUBLICATION_REL:
-					case OBJECT_ROLE:
 					case OBJECT_RULE:
 					case OBJECT_TABCONSTRAINT:
 					case OBJECT_TRANSFORM:
@@ -3543,6 +3545,9 @@ aclcheck_error(AclResult aclerr, ObjectType objtype,
 					case OBJECT_TSDICTIONARY:
 						msg = gettext_noop("must be owner of text search dictionary %s");
 						break;
+					case OBJECT_ROLE:
+						msg = gettext_noop("must be owner of role %s");
+						break;
 
 						/*
 						 * Special cases: For these, the error message talks
@@ -3567,7 +3572,6 @@ aclcheck_error(AclResult aclerr, ObjectType objtype,
 					case OBJECT_DEFACL:
 					case OBJECT_DOMCONSTRAINT:
 					case OBJECT_PUBLICATION_REL:
-					case OBJECT_ROLE:
 					case OBJECT_TRANSFORM:
 					case OBJECT_TSPARSER:
 					case OBJECT_TSTEMPLATE:
@@ -5428,16 +5432,62 @@ pg_statistics_object_ownercheck(Oid stat_oid, Oid roleid)
 	return has_privs_of_role(roleid, ownerId);
 }
 
+/*
+ * Check whether specified role is the direct or indirect owner of another
+ * role.
+ */
+bool
+pg_role_ownercheck(Oid role_oid, Oid roleid)
+{
+	HeapTuple	tuple;
+
+	/* Superusers bypass all permission checking. */
+	if (superuser_arg(roleid))
+		return true;
+
+	/*
+	 * Start with the owned role and traverse the ownership hierarchy upward.
+	 * We stop when we find the owner we are looking for or when we reach the
+	 * top.
+	 */
+	while (OidIsValid(role_oid))
+	{
+		Oid		owner_oid;
+
+		/* Find the owner of the current iteration's role */
+		tuple = SearchSysCache1(AUTHOID, ObjectIdGetDatum(role_oid));
+		if (!HeapTupleIsValid(tuple))
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_OBJECT),
+					 errmsg("role with OID %u does not exist",
+							role_oid)));
+		owner_oid = ((Form_pg_authid) GETSTRUCT(tuple))->rolowner;
+		ReleaseSysCache(tuple);
+
+		/* Have we found the target role? */
+		if (roleid == owner_oid)
+			return true;
+
+		/*
+		 * If we have reached a role which owns itself, we must iterate no
+		 * further, else we fall into an infinite loop.
+		 */
+		if (role_oid == owner_oid)
+			return false;
+
+		/* Set up for the next iteration. */
+		role_oid = owner_oid;
+	}
+
+	return false;
+}
+
 /*
  * Check whether specified role has CREATEROLE privilege (or is a superuser)
  *
- * Note: roles do not have owners per se; instead we use this test in
- * places where an ownership-like permissions test is needed for a role.
- * Be sure to apply it to the role trying to do the operation, not the
- * role being operated on!	Also note that this generally should not be
- * considered enough privilege if the target role is a superuser.
- * (We don't handle that consideration here because we want to give a
- * separate error message for such cases, so the caller has to deal with it.)
+ * Note: In versions prior to PostgreSQL version 15, roles did not have owners
+ * per se; instead we used this test in places where an ownership-like
+ * permissions test was needed for a role.
  */
 bool
 has_createrole_privilege(Oid roleid)
diff --git a/src/backend/catalog/objectaddress.c b/src/backend/catalog/objectaddress.c
index 8c94939baa..fecbc763de 100644
--- a/src/backend/catalog/objectaddress.c
+++ b/src/backend/catalog/objectaddress.c
@@ -2540,25 +2540,9 @@ check_object_ownership(Oid roleid, ObjectType objtype, ObjectAddress address,
 							   NameListToString(castNode(List, object)));
 			break;
 		case OBJECT_ROLE:
-
-			/*
-			 * We treat roles as being "owned" by those with CREATEROLE priv,
-			 * except that superusers are only owned by superusers.
-			 */
-			if (superuser_arg(address.objectId))
-			{
-				if (!superuser_arg(roleid))
-					ereport(ERROR,
-							(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
-							 errmsg("must be superuser")));
-			}
-			else
-			{
-				if (!has_createrole_privilege(roleid))
-					ereport(ERROR,
-							(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
-							 errmsg("must have CREATEROLE privilege")));
-			}
+			if (!pg_role_ownercheck(address.objectId, roleid))
+				aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
+							   strVal(object));
 			break;
 		case OBJECT_TSPARSER:
 		case OBJECT_TSTEMPLATE:
diff --git a/src/backend/commands/user.c b/src/backend/commands/user.c
index 815c7095ec..902c0473de 100644
--- a/src/backend/commands/user.c
+++ b/src/backend/commands/user.c
@@ -693,7 +693,7 @@ AlterRole(ParseState *pstate, AlterRoleStmt *stmt)
 			  !rolemembers &&
 			  !validUntil &&
 			  dpassword &&
-			  roleid == GetUserId()))
+			  !pg_role_ownercheck(roleid, GetUserId())))
 			ereport(ERROR,
 					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 					 errmsg("permission denied")));
@@ -894,7 +894,8 @@ AlterRoleSet(AlterRoleSetStmt *stmt)
 		}
 		else
 		{
-			if (!have_createrole_privilege() && roleid != GetUserId())
+			if (!have_createrole_privilege() &&
+				!pg_role_ownercheck(roleid, GetUserId()))
 				ereport(ERROR,
 						(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 						 errmsg("permission denied")));
@@ -946,11 +947,6 @@ DropRole(DropRoleStmt *stmt)
 				pg_auth_members_rel;
 	ListCell   *item;
 
-	if (!have_createrole_privilege())
-		ereport(ERROR,
-				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
-				 errmsg("permission denied to drop role")));
-
 	/*
 	 * Scan the pg_authid relation to find the Oid of the role(s) to be
 	 * deleted.
@@ -1022,6 +1018,12 @@ DropRole(DropRoleStmt *stmt)
 					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 					 errmsg("must be superuser to drop superusers")));
 
+		if (!have_createrole_privilege() &&
+			!pg_role_ownercheck(roleid, GetUserId()))
+			ereport(ERROR,
+					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+					 errmsg("permission denied to drop role")));
+
 		/* DROP hook for the role being removed */
 		InvokeObjectDropHook(AuthIdRelationId, roleid, 0);
 
diff --git a/src/backend/utils/adt/acl.c b/src/backend/utils/adt/acl.c
index 67f8b29434..04eae9d4e5 100644
--- a/src/backend/utils/adt/acl.c
+++ b/src/backend/utils/adt/acl.c
@@ -4850,6 +4850,10 @@ has_privs_of_role(Oid member, Oid role)
 	if (superuser_arg(member))
 		return true;
 
+	/* Owners of roles have every privilge the owned role has */
+	if (pg_role_ownercheck(role, member))
+		return true;
+
 	/*
 	 * Find all the roles that member has the privileges of, including
 	 * multi-level recursion, then see if target role is any one of them.
diff --git a/src/include/utils/acl.h b/src/include/utils/acl.h
index af771c901d..ec9d480d67 100644
--- a/src/include/utils/acl.h
+++ b/src/include/utils/acl.h
@@ -316,6 +316,7 @@ extern bool pg_extension_ownercheck(Oid ext_oid, Oid roleid);
 extern bool pg_publication_ownercheck(Oid pub_oid, Oid roleid);
 extern bool pg_subscription_ownercheck(Oid sub_oid, Oid roleid);
 extern bool pg_statistics_object_ownercheck(Oid stat_oid, Oid roleid);
+extern bool pg_role_ownercheck(Oid role_oid, Oid roleid);
 extern bool has_createrole_privilege(Oid roleid);
 extern bool has_bypassrls_privilege(Oid roleid);
 
diff --git a/src/test/modules/dummy_seclabel/expected/dummy_seclabel.out b/src/test/modules/dummy_seclabel/expected/dummy_seclabel.out
index b2d898a7d1..93cf82b750 100644
--- a/src/test/modules/dummy_seclabel/expected/dummy_seclabel.out
+++ b/src/test/modules/dummy_seclabel/expected/dummy_seclabel.out
@@ -7,8 +7,11 @@ SET client_min_messages TO 'warning';
 DROP ROLE IF EXISTS regress_dummy_seclabel_user1;
 DROP ROLE IF EXISTS regress_dummy_seclabel_user2;
 RESET client_min_messages;
-CREATE USER regress_dummy_seclabel_user1 WITH CREATEROLE;
+CREATE USER regress_dummy_seclabel_user0 WITH CREATEROLE;
+SET SESSION AUTHORIZATION regress_dummy_seclabel_user0;
+CREATE USER regress_dummy_seclabel_user1;
 CREATE USER regress_dummy_seclabel_user2;
+RESET SESSION AUTHORIZATION;
 CREATE TABLE dummy_seclabel_tbl1 (a int, b text);
 CREATE TABLE dummy_seclabel_tbl2 (x int, y text);
 CREATE VIEW dummy_seclabel_view1 AS SELECT * FROM dummy_seclabel_tbl2;
@@ -19,7 +22,7 @@ ALTER TABLE dummy_seclabel_tbl2 OWNER TO regress_dummy_seclabel_user2;
 --
 -- Test of SECURITY LABEL statement with a plugin
 --
-SET SESSION AUTHORIZATION regress_dummy_seclabel_user1;
+SET SESSION AUTHORIZATION regress_dummy_seclabel_user0;
 SECURITY LABEL ON TABLE dummy_seclabel_tbl1 IS 'classified';			-- OK
 SECURITY LABEL ON COLUMN dummy_seclabel_tbl1.a IS 'unclassified';		-- OK
 SECURITY LABEL ON COLUMN dummy_seclabel_tbl1 IS 'unclassified';	-- fail
@@ -29,6 +32,7 @@ ERROR:  '...invalid label...' is not a valid security label
 SECURITY LABEL FOR 'dummy' ON TABLE dummy_seclabel_tbl1 IS 'unclassified';	-- OK
 SECURITY LABEL FOR 'unknown_seclabel' ON TABLE dummy_seclabel_tbl1 IS 'classified';	-- fail
 ERROR:  security label provider "unknown_seclabel" is not loaded
+SET SESSION AUTHORIZATION regress_dummy_seclabel_user1;
 SECURITY LABEL ON TABLE dummy_seclabel_tbl2 IS 'unclassified';	-- fail (not owner)
 ERROR:  must be owner of table dummy_seclabel_tbl2
 SECURITY LABEL ON TABLE dummy_seclabel_tbl1 IS 'secret';		-- fail (not superuser)
@@ -42,7 +46,7 @@ SECURITY LABEL ON TABLE dummy_seclabel_tbl2 IS 'classified';			-- OK
 --
 -- Test for shared database object
 --
-SET SESSION AUTHORIZATION regress_dummy_seclabel_user1;
+SET SESSION AUTHORIZATION regress_dummy_seclabel_user0;
 SECURITY LABEL ON ROLE regress_dummy_seclabel_user1 IS 'classified';			-- OK
 SECURITY LABEL ON ROLE regress_dummy_seclabel_user1 IS '...invalid label...';	-- fail
 ERROR:  '...invalid label...' is not a valid security label
@@ -55,7 +59,7 @@ SECURITY LABEL ON ROLE regress_dummy_seclabel_user3 IS 'unclassified';	-- fail (
 ERROR:  role "regress_dummy_seclabel_user3" does not exist
 SET SESSION AUTHORIZATION regress_dummy_seclabel_user2;
 SECURITY LABEL ON ROLE regress_dummy_seclabel_user2 IS 'unclassified';	-- fail (not privileged)
-ERROR:  must have CREATEROLE privilege
+ERROR:  must be owner of role regress_dummy_seclabel_user2
 RESET SESSION AUTHORIZATION;
 --
 -- Test for various types of object
diff --git a/src/test/modules/dummy_seclabel/sql/dummy_seclabel.sql b/src/test/modules/dummy_seclabel/sql/dummy_seclabel.sql
index 8c347b6a68..bf575343cf 100644
--- a/src/test/modules/dummy_seclabel/sql/dummy_seclabel.sql
+++ b/src/test/modules/dummy_seclabel/sql/dummy_seclabel.sql
@@ -11,8 +11,12 @@ DROP ROLE IF EXISTS regress_dummy_seclabel_user2;
 
 RESET client_min_messages;
 
-CREATE USER regress_dummy_seclabel_user1 WITH CREATEROLE;
+CREATE USER regress_dummy_seclabel_user0 WITH CREATEROLE;
+
+SET SESSION AUTHORIZATION regress_dummy_seclabel_user0;
+CREATE USER regress_dummy_seclabel_user1;
 CREATE USER regress_dummy_seclabel_user2;
+RESET SESSION AUTHORIZATION;
 
 CREATE TABLE dummy_seclabel_tbl1 (a int, b text);
 CREATE TABLE dummy_seclabel_tbl2 (x int, y text);
@@ -26,7 +30,7 @@ ALTER TABLE dummy_seclabel_tbl2 OWNER TO regress_dummy_seclabel_user2;
 --
 -- Test of SECURITY LABEL statement with a plugin
 --
-SET SESSION AUTHORIZATION regress_dummy_seclabel_user1;
+SET SESSION AUTHORIZATION regress_dummy_seclabel_user0;
 
 SECURITY LABEL ON TABLE dummy_seclabel_tbl1 IS 'classified';			-- OK
 SECURITY LABEL ON COLUMN dummy_seclabel_tbl1.a IS 'unclassified';		-- OK
@@ -34,6 +38,8 @@ SECURITY LABEL ON COLUMN dummy_seclabel_tbl1 IS 'unclassified';	-- fail
 SECURITY LABEL ON TABLE dummy_seclabel_tbl1 IS '...invalid label...';	-- fail
 SECURITY LABEL FOR 'dummy' ON TABLE dummy_seclabel_tbl1 IS 'unclassified';	-- OK
 SECURITY LABEL FOR 'unknown_seclabel' ON TABLE dummy_seclabel_tbl1 IS 'classified';	-- fail
+
+SET SESSION AUTHORIZATION regress_dummy_seclabel_user1;
 SECURITY LABEL ON TABLE dummy_seclabel_tbl2 IS 'unclassified';	-- fail (not owner)
 SECURITY LABEL ON TABLE dummy_seclabel_tbl1 IS 'secret';		-- fail (not superuser)
 SECURITY LABEL ON TABLE dummy_seclabel_tbl3 IS 'unclassified';	-- fail (not found)
@@ -45,7 +51,7 @@ SECURITY LABEL ON TABLE dummy_seclabel_tbl2 IS 'classified';			-- OK
 --
 -- Test for shared database object
 --
-SET SESSION AUTHORIZATION regress_dummy_seclabel_user1;
+SET SESSION AUTHORIZATION regress_dummy_seclabel_user0;
 
 SECURITY LABEL ON ROLE regress_dummy_seclabel_user1 IS 'classified';			-- OK
 SECURITY LABEL ON ROLE regress_dummy_seclabel_user1 IS '...invalid label...';	-- fail
diff --git a/src/test/regress/expected/create_role.out b/src/test/regress/expected/create_role.out
index 385ee74342..a4eb19c954 100644
--- a/src/test/regress/expected/create_role.out
+++ b/src/test/regress/expected/create_role.out
@@ -58,21 +58,18 @@ CREATE TABLE regress_tbl_22 (i integer);
 CREATE INDEX regress_idx_22 ON regress_tbl_22(i);
 CREATE VIEW regress_view_22 AS SELECT * FROM pg_catalog.pg_class;
 REVOKE ALL PRIVILEGES ON regress_tbl_22 FROM PUBLIC;
--- fail, these objects belonging to regress_role_22
+-- ok, owning role can manage owned role's objects
 SET SESSION AUTHORIZATION regress_role_7;
 DROP INDEX regress_idx_22;
-ERROR:  must be owner of index regress_idx_22
 ALTER TABLE regress_tbl_22 ADD COLUMN t text;
-ERROR:  must be owner of table regress_tbl_22
 DROP TABLE regress_tbl_22;
-ERROR:  must be owner of table regress_tbl_22
+-- fail, not a member of target role
 ALTER VIEW regress_view_22 OWNER TO regress_role_1;
-ERROR:  must be owner of view regress_view_22
+ERROR:  must be member of role "regress_role_1"
+-- ok
 DROP VIEW regress_view_22;
-ERROR:  must be owner of view regress_view_22
 -- fail, cannot take ownership of these objects from regress_role_22
 REASSIGN OWNED BY regress_role_22 TO regress_role_7;
-ERROR:  permission denied to reassign objects
 -- ok, having CREATEROLE is enough to create roles in privileged roles
 CREATE ROLE regress_role_23 IN ROLE pg_read_all_data;
 CREATE ROLE regress_role_24 IN ROLE pg_write_all_data;
@@ -152,13 +149,8 @@ DROP ROLE regress_role_31;
 DROP ROLE regress_role_32;
 -- fail, role still owns database objects
 DROP ROLE regress_role_22;
-ERROR:  role "regress_role_22" cannot be dropped because some objects depend on it
-DETAIL:  owner of table regress_tbl_22
-owner of view regress_view_22
 -- fail, role still owns other roles
 DROP ROLE regress_role_7;
-ERROR:  role "regress_role_7" cannot be dropped because some objects depend on it
-DETAIL:  owner of role regress_role_22
 -- fail, cannot drop ourself nor superusers
 DROP ROLE regress_role_super;
 ERROR:  must be superuser to drop superusers
@@ -166,10 +158,5 @@ DROP ROLE regress_role_1;
 ERROR:  current user cannot be dropped
 -- ok
 RESET SESSION AUTHORIZATION;
-DROP INDEX regress_idx_22;
-DROP TABLE regress_tbl_22;
-DROP VIEW regress_view_22;
-DROP ROLE regress_role_22;
-DROP ROLE regress_role_7;
 DROP ROLE regress_role_1;
 DROP ROLE regress_role_super;
diff --git a/src/test/regress/sql/create_role.sql b/src/test/regress/sql/create_role.sql
index 728208f1e1..df8d34a8d5 100644
--- a/src/test/regress/sql/create_role.sql
+++ b/src/test/regress/sql/create_role.sql
@@ -63,12 +63,16 @@ CREATE INDEX regress_idx_22 ON regress_tbl_22(i);
 CREATE VIEW regress_view_22 AS SELECT * FROM pg_catalog.pg_class;
 REVOKE ALL PRIVILEGES ON regress_tbl_22 FROM PUBLIC;
 
--- fail, these objects belonging to regress_role_22
+-- ok, owning role can manage owned role's objects
 SET SESSION AUTHORIZATION regress_role_7;
 DROP INDEX regress_idx_22;
 ALTER TABLE regress_tbl_22 ADD COLUMN t text;
 DROP TABLE regress_tbl_22;
+
+-- fail, not a member of target role
 ALTER VIEW regress_view_22 OWNER TO regress_role_1;
+
+-- ok
 DROP VIEW regress_view_22;
 
 -- fail, cannot take ownership of these objects from regress_role_22
@@ -135,10 +139,5 @@ DROP ROLE regress_role_1;
 
 -- ok
 RESET SESSION AUTHORIZATION;
-DROP INDEX regress_idx_22;
-DROP TABLE regress_tbl_22;
-DROP VIEW regress_view_22;
-DROP ROLE regress_role_22;
-DROP ROLE regress_role_7;
 DROP ROLE regress_role_1;
 DROP ROLE regress_role_super;
-- 
2.21.1 (Apple Git-122.3)