Avoid repeated name lookups during table and index DDL.

If the name lookups come to different conclusions due to concurrent
activity, we might perform some parts of the DDL on a different table
than other parts.  At least in the case of CREATE INDEX, this can be
used to cause the permissions checks to be performed against a
different table than the index creation, allowing for a privilege
escalation attack.

This changes the calling convention for DefineIndex, CreateTrigger,
transformIndexStmt, transformAlterTableStmt, CheckIndexCompatible
(in 9.2 and newer), and AlterTable (in 9.1 and older).  In addition,
CheckRelationOwnership is removed in 9.2 and newer and the calling
convention is changed in older branches.  A field has also been added
to the Constraint node (FkConstraint in 8.4).  Third-party code calling
these functions or using the Constraint node will require updating.

Report by Andres Freund.  Patch by Robert Haas and Andres Freund,
reviewed by Tom Lane.

Security: CVE-2014-0062

src/include/catalog/pg_constraint.h

@@ -247,6 +247,7 @@ extern char *ChooseConstraintName(const char *name1, const char *name2,
 
 extern void AlterConstraintNamespaces(Oid ownerId, Oid oldNspId,
 					  Oid newNspId, bool isType, ObjectAddresses *objsMoved);
+extern void get_constraint_relation_oids(Oid constraint_oid, Oid *conrelid, Oid *confrelid);
 extern Oid	get_relation_constraint_oid(Oid relid, const char *conname, bool missing_ok);
 extern Oid	get_domain_constraint_oid(Oid typid, const char *conname, bool missing_ok);
 

src/include/commands/defrem.h

@@ -20,7 +20,8 @@
 extern void RemoveObjects(DropStmt *stmt);
 
 /* commands/indexcmds.c */
-extern Oid DefineIndex(IndexStmt *stmt,
+extern Oid DefineIndex(Oid relationId,
+			IndexStmt *stmt,
 			Oid indexRelationId,
 			bool is_alter_table,
 			bool check_rights,
@@ -35,7 +36,6 @@ extern char *makeObjectName(const char *name1, const char *name2,
 extern char *ChooseRelationName(const char *name1, const char *name2,
 				   const char *label, Oid namespaceid);
 extern bool CheckIndexCompatible(Oid oldId,
-					 RangeVar *heapRelation,
 					 char *accessMethodName,
 					 List *attributeList,
 					 List *exclusionOpNames);

src/include/commands/tablecmds.h

@@ -78,4 +78,6 @@ extern void AtEOSubXact_on_commit_actions(bool isCommit,
 extern void RangeVarCallbackOwnsTable(const RangeVar *relation,
 						  Oid relId, Oid oldRelId, void *arg);
 
+extern void RangeVarCallbackOwnsRelation(const RangeVar *relation,
+						  Oid relId, Oid oldRelId, void *noCatalogs);
 #endif   /* TABLECMDS_H */

src/include/commands/trigger.h

@@ -109,7 +109,7 @@ extern PGDLLIMPORT int SessionReplicationRole;
 #define TRIGGER_DISABLED					'D'
 
 extern Oid CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
-			  Oid constraintOid, Oid indexOid,
+			  Oid relOid, Oid refRelOid, Oid constraintOid, Oid indexOid,
 			  bool isInternal);
 
 extern void RemoveTriggerById(Oid trigOid);

src/include/nodes/parsenodes.h

@@ -1583,6 +1583,8 @@ typedef struct Constraint
 	/* Fields used for constraints that allow a NOT VALID specification */
 	bool		skip_validation;	/* skip validation of existing rows? */
 	bool		initially_valid;	/* mark the new constraint as valid? */
+
+	Oid			old_pktable_oid; /* pg_constraint.confrelid of my former self */
 } Constraint;
 
 /* ----------------------

src/include/parser/parse_utilcmd.h

@@ -18,9 +18,10 @@
 
 
 extern List *transformCreateStmt(CreateStmt *stmt, const char *queryString);
-extern List *transformAlterTableStmt(AlterTableStmt *stmt,
+extern List *transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 						const char *queryString);
-extern IndexStmt *transformIndexStmt(IndexStmt *stmt, const char *queryString);
+extern IndexStmt *transformIndexStmt(Oid relid, IndexStmt *stmt,
+				   const char *queryString);
 extern void transformRuleStmt(RuleStmt *stmt, const char *queryString,
 				  List **actions, Node **whereClause);
 extern List *transformCreateSchemaStmt(CreateSchemaStmt *stmt);

src/include/tcop/utility.h

@@ -49,6 +49,4 @@ extern LogStmtLevel GetCommandLogLevel(Node *parsetree);
 
 extern bool CommandIsReadOnly(Node *parsetree);
 
-extern void CheckRelationOwnership(RangeVar *rel, bool noCatalogs);
-
 #endif   /* UTILITY_H */