codekingpro/portable-devtools

1/*2 * objectaccess.h3 *4 *		Object access hooks.5 *6 * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group7 * Portions Copyright (c) 1994, Regents of the University of California8 */9 10#ifndef OBJECTACCESS_H11#define OBJECTACCESS_H12 13/*14 * Object access hooks are intended to be called just before or just after15 * performing certain actions on a SQL object.  This is intended as16 * infrastructure for security or logging plugins.17 *18 * OAT_POST_CREATE should be invoked just after the object is created.19 * Typically, this is done after inserting the primary catalog records and20 * associated dependencies. The command counter may or may not be incremented21 * at the time the hook is invoked; if not, the extension can use SnapshotSelf22 * to get the new version of the tuple.23 *24 * OAT_DROP should be invoked just before deletion of objects; typically25 * deleteOneObject(). Its arguments are packed within ObjectAccessDrop.26 *27 * OAT_POST_ALTER should be invoked just after the object is altered,28 * but before the command counter is incremented.  An extension using the29 * hook can use a current MVCC snapshot to get the old version of the tuple,30 * and can use SnapshotSelf to get the new version of the tuple.31 *32 * OAT_NAMESPACE_SEARCH should be invoked prior to object name lookup under33 * a particular namespace. This event is equivalent to usage permission34 * on a schema under the default access control mechanism.35 *36 * OAT_FUNCTION_EXECUTE should be invoked prior to function execution.37 * This event is almost equivalent to execute permission on functions,38 * except for the case when execute permission is checked during object39 * creation or altering, because OAT_POST_CREATE or OAT_POST_ALTER are40 * sufficient for extensions to track these kind of checks.41 *42 * OAT_TRUNCATE should be invoked just before truncation of objects. This43 * event is equivalent to truncate permission on a relation under the44 * default access control mechanism.45 *46 * Other types may be added in the future.47 */48typedef enum ObjectAccessType49{50	OAT_POST_CREATE,51	OAT_DROP,52	OAT_POST_ALTER,53	OAT_NAMESPACE_SEARCH,54	OAT_FUNCTION_EXECUTE,55	OAT_TRUNCATE56} ObjectAccessType;57 58/*59 * Arguments of OAT_POST_CREATE event60 */61typedef struct62{63	/*64	 * This flag informs extensions whether the context of this creation is65	 * invoked by user's operations, or not. E.g, it shall be dealt as66	 * internal stuff on toast tables or indexes due to type changes.67	 */68	bool		is_internal;69} ObjectAccessPostCreate;70 71/*72 * Arguments of OAT_DROP event73 */74typedef struct75{76	/*77	 * Flags to inform extensions the context of this deletion. Also see78	 * PERFORM_DELETION_* in dependency.h79	 */80	int			dropflags;81} ObjectAccessDrop;82 83/*84 * Arguments of OAT_POST_ALTER event85 */86typedef struct87{88	/*89	 * This identifier is used when system catalog takes two IDs to identify a90	 * particular tuple of the catalog. It is only used when the caller want91	 * to identify an entry of pg_inherits, pg_db_role_setting or92	 * pg_user_mapping. Elsewhere, InvalidOid should be set.93	 */94	Oid			auxiliary_id;95 96	/*97	 * If this flag is set, the user hasn't requested that the object be98	 * altered, but we're doing it anyway for some internal reason.99	 * Permissions-checking hooks may want to skip checks if, say, we're alter100	 * the constraints of a temporary heap during CLUSTER.101	 */102	bool		is_internal;103} ObjectAccessPostAlter;104 105/*106 * Arguments of OAT_NAMESPACE_SEARCH107 */108typedef struct109{110	/*111	 * If true, hook should report an error when permission to search this112	 * schema is denied.113	 */114	bool		ereport_on_violation;115 116	/*117	 * This is, in essence, an out parameter.  Core code should initialize118	 * this to true, and any extension that wants to deny access should reset119	 * it to false.  But an extension should be careful never to store a true120	 * value here, so that in case there are multiple extensions access is121	 * only allowed if all extensions agree.122	 */123	bool		result;124} ObjectAccessNamespaceSearch;125 126/* Plugin provides a hook function matching one or both of these signatures. */127typedef void (*object_access_hook_type) (ObjectAccessType access,128										 Oid classId,129										 Oid objectId,130										 int subId,131										 void *arg);132 133typedef void (*object_access_hook_type_str) (ObjectAccessType access,134											 Oid classId,135											 const char *objectStr,136											 int subId,137											 void *arg);138 139/* Plugin sets this variable to a suitable hook function. */140extern PGDLLIMPORT object_access_hook_type object_access_hook;141extern PGDLLIMPORT object_access_hook_type_str object_access_hook_str;142 143 144/* Core code uses these functions to call the hook (see macros below). */145extern void RunObjectPostCreateHook(Oid classId, Oid objectId, int subId,146									bool is_internal);147extern void RunObjectDropHook(Oid classId, Oid objectId, int subId,148							  int dropflags);149extern void RunObjectTruncateHook(Oid objectId);150extern void RunObjectPostAlterHook(Oid classId, Oid objectId, int subId,151								   Oid auxiliaryId, bool is_internal);152extern bool RunNamespaceSearchHook(Oid objectId, bool ereport_on_violation);153extern void RunFunctionExecuteHook(Oid objectId);154 155/* String versions */156extern void RunObjectPostCreateHookStr(Oid classId, const char *objectName, int subId,157									   bool is_internal);158extern void RunObjectDropHookStr(Oid classId, const char *objectName, int subId,159								 int dropflags);160extern void RunObjectTruncateHookStr(const char *objectName);161extern void RunObjectPostAlterHookStr(Oid classId, const char *objectName, int subId,162									  Oid auxiliaryId, bool is_internal);163extern bool RunNamespaceSearchHookStr(const char *objectName, bool ereport_on_violation);164extern void RunFunctionExecuteHookStr(const char *objectName);165 166 167/*168 * The following macros are wrappers around the functions above; these should169 * normally be used to invoke the hook in lieu of calling the above functions170 * directly.171 */172 173#define InvokeObjectPostCreateHook(classId,objectId,subId)			\174	InvokeObjectPostCreateHookArg((classId),(objectId),(subId),false)175#define InvokeObjectPostCreateHookArg(classId,objectId,subId,is_internal) \176	do {															\177		if (object_access_hook)										\178			RunObjectPostCreateHook((classId),(objectId),(subId),	\179									(is_internal));					\180	} while(0)181 182#define InvokeObjectDropHook(classId,objectId,subId)				\183	InvokeObjectDropHookArg((classId),(objectId),(subId),0)184#define InvokeObjectDropHookArg(classId,objectId,subId,dropflags)	\185	do {															\186		if (object_access_hook)										\187			RunObjectDropHook((classId),(objectId),(subId),			\188							  (dropflags));							\189	} while(0)190 191#define InvokeObjectTruncateHook(objectId)							\192	do {															\193		if (object_access_hook)										\194			RunObjectTruncateHook(objectId);						\195	} while(0)196 197#define InvokeObjectPostAlterHook(classId,objectId,subId)			\198	InvokeObjectPostAlterHookArg((classId),(objectId),(subId),		\199								 InvalidOid,false)200#define InvokeObjectPostAlterHookArg(classId,objectId,subId,		\201									 auxiliaryId,is_internal)		\202	do {															\203		if (object_access_hook)										\204			RunObjectPostAlterHook((classId),(objectId),(subId),	\205								   (auxiliaryId),(is_internal));	\206	} while(0)207 208#define InvokeNamespaceSearchHook(objectId, ereport_on_violation)	\209	(!object_access_hook											\210	 ? true															\211	 : RunNamespaceSearchHook((objectId), (ereport_on_violation)))212 213#define InvokeFunctionExecuteHook(objectId)		\214	do {										\215		if (object_access_hook)					\216			RunFunctionExecuteHook(objectId);	\217	} while(0)218 219 220#define InvokeObjectPostCreateHookStr(classId,objectName,subId)			\221	InvokeObjectPostCreateHookArgStr((classId),(objectName),(subId),false)222#define InvokeObjectPostCreateHookArgStr(classId,objectName,subId,is_internal) \223	do {															\224		if (object_access_hook_str)										\225			RunObjectPostCreateHookStr((classId),(objectName),(subId),	\226									(is_internal));					\227	} while(0)228 229#define InvokeObjectDropHookStr(classId,objectName,subId)				\230	InvokeObjectDropHookArgStr((classId),(objectName),(subId),0)231#define InvokeObjectDropHookArgStr(classId,objectName,subId,dropflags)	\232	do {															\233		if (object_access_hook_str)										\234			RunObjectDropHookStr((classId),(objectName),(subId),			\235							  (dropflags));							\236	} while(0)237 238#define InvokeObjectTruncateHookStr(objectName)							\239	do {															\240		if (object_access_hook_str)										\241			RunObjectTruncateHookStr(objectName);						\242	} while(0)243 244#define InvokeObjectPostAlterHookStr(classId,objectName,subId)			\245	InvokeObjectPostAlterHookArgStr((classId),(objectName),(subId),		\246								 InvalidOid,false)247#define InvokeObjectPostAlterHookArgStr(classId,objectName,subId,		\248									 auxiliaryId,is_internal)		\249	do {															\250		if (object_access_hook_str)										\251			RunObjectPostAlterHookStr((classId),(objectName),(subId),	\252								   (auxiliaryId),(is_internal));	\253	} while(0)254 255#define InvokeNamespaceSearchHookStr(objectName, ereport_on_violation)	\256	(!object_access_hook_str										\257	 ? true															\258	 : RunNamespaceSearchHookStr((objectName), (ereport_on_violation)))259 260#define InvokeFunctionExecuteHookStr(objectName)		\261	do {										\262		if (object_access_hook_str)					\263			RunFunctionExecuteHookStr(objectName);	\264	} while(0)265 266 267#endif							/* OBJECTACCESS_H */268