postgresql/src/include/utils/acl.h
Alvaro Herrera 7b504eb282 Implement multivariate n-distinct coefficients
Add support for explicitly declared statistic objects (CREATE
STATISTICS), allowing collection of statistics on more complex
combinations that individual table columns.  Companion commands DROP
STATISTICS and ALTER STATISTICS ... OWNER TO / SET SCHEMA / RENAME are
added too.  All this DDL has been designed so that more statistic types
can be added later on, such as multivariate most-common-values and
multivariate histograms between columns of a single table, leaving room
for permitting columns on multiple tables, too, as well as expressions.

This commit only adds support for collection of n-distinct coefficient
on user-specified sets of columns in a single table.  This is useful to
estimate number of distinct groups in GROUP BY and DISTINCT clauses;
estimation errors there can cause over-allocation of memory in hashed
aggregates, for instance, so it's a worthwhile problem to solve.  A new
special pseudo-type pg_ndistinct is used.

(num-distinct estimation was deemed sufficiently useful by itself that
this is worthwhile even if no further statistic types are added
immediately; so much so that another version of essentially the same
functionality was submitted by Kyotaro Horiguchi:
https://postgr.es/m/20150828.173334.114731693.horiguchi.kyotaro@lab.ntt.co.jp
though this commit does not use that code.)

Author: Tomas Vondra.  Some code rework by Álvaro.
Reviewed-by: Dean Rasheed, David Rowley, Kyotaro Horiguchi, Jeff Janes,
    Ideriha Takeshi
Discussion: https://postgr.es/m/543AFA15.4080608@fuzzy.cz
    https://postgr.es/m/20170320190220.ixlaueanxegqd5gr@alvherre.pgsql
2017-03-24 14:06:10 -03:00

334 lines
13 KiB
C

/*-------------------------------------------------------------------------
*
* acl.h
* Definition of (and support for) access control list data structures.
*
*
* Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/utils/acl.h
*
* NOTES
* An ACL array is simply an array of AclItems, representing the union
* of the privileges represented by the individual items. A zero-length
* array represents "no privileges". There are no assumptions about the
* ordering of the items, but we do expect that there are no two entries
* in the array with the same grantor and grantee.
*
* For backward-compatibility purposes we have to allow null ACL entries
* in system catalogs. A null ACL will be treated as meaning "default
* protection" (i.e., whatever acldefault() returns).
*-------------------------------------------------------------------------
*/
#ifndef ACL_H
#define ACL_H
#include "access/htup.h"
#include "nodes/parsenodes.h"
#include "parser/parse_node.h"
#include "utils/array.h"
#include "utils/snapshot.h"
/*
* typedef AclMode is declared in parsenodes.h, also the individual privilege
* bit meanings are defined there
*/
#define ACL_ID_PUBLIC 0 /* placeholder for id in a PUBLIC acl item */
/*
* AclItem
*
* Note: must be same size on all platforms, because the size is hardcoded
* in the pg_type.h entry for aclitem.
*/
typedef struct AclItem
{
Oid ai_grantee; /* ID that this item grants privs to */
Oid ai_grantor; /* grantor of privs */
AclMode ai_privs; /* privilege bits */
} AclItem;
/*
* The upper 16 bits of the ai_privs field of an AclItem are the grant option
* bits, and the lower 16 bits are the actual privileges. We use "rights"
* to mean the combined grant option and privilege bits fields.
*/
#define ACLITEM_GET_PRIVS(item) ((item).ai_privs & 0xFFFF)
#define ACLITEM_GET_GOPTIONS(item) (((item).ai_privs >> 16) & 0xFFFF)
#define ACLITEM_GET_RIGHTS(item) ((item).ai_privs)
#define ACL_GRANT_OPTION_FOR(privs) (((AclMode) (privs) & 0xFFFF) << 16)
#define ACL_OPTION_TO_PRIVS(privs) (((AclMode) (privs) >> 16) & 0xFFFF)
#define ACLITEM_SET_PRIVS(item,privs) \
((item).ai_privs = ((item).ai_privs & ~((AclMode) 0xFFFF)) | \
((AclMode) (privs) & 0xFFFF))
#define ACLITEM_SET_GOPTIONS(item,goptions) \
((item).ai_privs = ((item).ai_privs & ~(((AclMode) 0xFFFF) << 16)) | \
(((AclMode) (goptions) & 0xFFFF) << 16))
#define ACLITEM_SET_RIGHTS(item,rights) \
((item).ai_privs = (AclMode) (rights))
#define ACLITEM_SET_PRIVS_GOPTIONS(item,privs,goptions) \
((item).ai_privs = ((AclMode) (privs) & 0xFFFF) | \
(((AclMode) (goptions) & 0xFFFF) << 16))
#define ACLITEM_ALL_PRIV_BITS ((AclMode) 0xFFFF)
#define ACLITEM_ALL_GOPTION_BITS ((AclMode) 0xFFFF << 16)
/*
* Definitions for convenient access to Acl (array of AclItem).
* These are standard PostgreSQL arrays, but are restricted to have one
* dimension and no nulls. We also ignore the lower bound when reading,
* and set it to one when writing.
*
* CAUTION: as of PostgreSQL 7.1, these arrays are toastable (just like all
* other array types). Therefore, be careful to detoast them with the
* macros provided, unless you know for certain that a particular array
* can't have been toasted.
*/
/*
* Acl a one-dimensional array of AclItem
*/
typedef ArrayType Acl;
#define ACL_NUM(ACL) (ARR_DIMS(ACL)[0])
#define ACL_DAT(ACL) ((AclItem *) ARR_DATA_PTR(ACL))
#define ACL_N_SIZE(N) (ARR_OVERHEAD_NONULLS(1) + ((N) * sizeof(AclItem)))
#define ACL_SIZE(ACL) ARR_SIZE(ACL)
/*
* fmgr macros for these types
*/
#define DatumGetAclItemP(X) ((AclItem *) DatumGetPointer(X))
#define PG_GETARG_ACLITEM_P(n) DatumGetAclItemP(PG_GETARG_DATUM(n))
#define PG_RETURN_ACLITEM_P(x) PG_RETURN_POINTER(x)
#define DatumGetAclP(X) ((Acl *) PG_DETOAST_DATUM(X))
#define DatumGetAclPCopy(X) ((Acl *) PG_DETOAST_DATUM_COPY(X))
#define PG_GETARG_ACL_P(n) DatumGetAclP(PG_GETARG_DATUM(n))
#define PG_GETARG_ACL_P_COPY(n) DatumGetAclPCopy(PG_GETARG_DATUM(n))
#define PG_RETURN_ACL_P(x) PG_RETURN_POINTER(x)
/*
* ACL modification opcodes for aclupdate
*/
#define ACL_MODECHG_ADD 1
#define ACL_MODECHG_DEL 2
#define ACL_MODECHG_EQL 3
/*
* External representations of the privilege bits --- aclitemin/aclitemout
* represent each possible privilege bit with a distinct 1-character code
*/
#define ACL_INSERT_CHR 'a' /* formerly known as "append" */
#define ACL_SELECT_CHR 'r' /* formerly known as "read" */
#define ACL_UPDATE_CHR 'w' /* formerly known as "write" */
#define ACL_DELETE_CHR 'd'
#define ACL_TRUNCATE_CHR 'D' /* super-delete, as it were */
#define ACL_REFERENCES_CHR 'x'
#define ACL_TRIGGER_CHR 't'
#define ACL_EXECUTE_CHR 'X'
#define ACL_USAGE_CHR 'U'
#define ACL_CREATE_CHR 'C'
#define ACL_CREATE_TEMP_CHR 'T'
#define ACL_CONNECT_CHR 'c'
/* string holding all privilege code chars, in order by bitmask position */
#define ACL_ALL_RIGHTS_STR "arwdDxtXUCTc"
/*
* Bitmasks defining "all rights" for each supported object type
*/
#define ACL_ALL_RIGHTS_COLUMN (ACL_INSERT|ACL_SELECT|ACL_UPDATE|ACL_REFERENCES)
#define ACL_ALL_RIGHTS_RELATION (ACL_INSERT|ACL_SELECT|ACL_UPDATE|ACL_DELETE|ACL_TRUNCATE|ACL_REFERENCES|ACL_TRIGGER)
#define ACL_ALL_RIGHTS_SEQUENCE (ACL_USAGE|ACL_SELECT|ACL_UPDATE)
#define ACL_ALL_RIGHTS_DATABASE (ACL_CREATE|ACL_CREATE_TEMP|ACL_CONNECT)
#define ACL_ALL_RIGHTS_FDW (ACL_USAGE)
#define ACL_ALL_RIGHTS_FOREIGN_SERVER (ACL_USAGE)
#define ACL_ALL_RIGHTS_FUNCTION (ACL_EXECUTE)
#define ACL_ALL_RIGHTS_LANGUAGE (ACL_USAGE)
#define ACL_ALL_RIGHTS_LARGEOBJECT (ACL_SELECT|ACL_UPDATE)
#define ACL_ALL_RIGHTS_NAMESPACE (ACL_USAGE|ACL_CREATE)
#define ACL_ALL_RIGHTS_TABLESPACE (ACL_CREATE)
#define ACL_ALL_RIGHTS_TYPE (ACL_USAGE)
/* operation codes for pg_*_aclmask */
typedef enum
{
ACLMASK_ALL, /* normal case: compute all bits */
ACLMASK_ANY /* return when result is known nonzero */
} AclMaskHow;
/* result codes for pg_*_aclcheck */
typedef enum
{
ACLCHECK_OK = 0,
ACLCHECK_NO_PRIV,
ACLCHECK_NOT_OWNER
} AclResult;
/* this enum covers all object types that can have privilege errors */
/* currently it's only used to tell aclcheck_error what to say */
typedef enum AclObjectKind
{
ACL_KIND_COLUMN, /* pg_attribute */
ACL_KIND_CLASS, /* pg_class */
ACL_KIND_SEQUENCE, /* pg_sequence */
ACL_KIND_DATABASE, /* pg_database */
ACL_KIND_PROC, /* pg_proc */
ACL_KIND_OPER, /* pg_operator */
ACL_KIND_TYPE, /* pg_type */
ACL_KIND_LANGUAGE, /* pg_language */
ACL_KIND_LARGEOBJECT, /* pg_largeobject */
ACL_KIND_NAMESPACE, /* pg_namespace */
ACL_KIND_OPCLASS, /* pg_opclass */
ACL_KIND_OPFAMILY, /* pg_opfamily */
ACL_KIND_COLLATION, /* pg_collation */
ACL_KIND_CONVERSION, /* pg_conversion */
ACL_KIND_STATISTICS, /* pg_statistic_ext */
ACL_KIND_TABLESPACE, /* pg_tablespace */
ACL_KIND_TSDICTIONARY, /* pg_ts_dict */
ACL_KIND_TSCONFIGURATION, /* pg_ts_config */
ACL_KIND_FDW, /* pg_foreign_data_wrapper */
ACL_KIND_FOREIGN_SERVER, /* pg_foreign_server */
ACL_KIND_EVENT_TRIGGER, /* pg_event_trigger */
ACL_KIND_EXTENSION, /* pg_extension */
ACL_KIND_PUBLICATION, /* pg_publication */
ACL_KIND_SUBSCRIPTION, /* pg_subscription */
MAX_ACL_KIND /* MUST BE LAST */
} AclObjectKind;
/*
* routines used internally
*/
extern Acl *acldefault(GrantObjectType objtype, Oid ownerId);
extern Acl *get_user_default_acl(GrantObjectType objtype, Oid ownerId,
Oid nsp_oid);
extern Acl *aclupdate(const Acl *old_acl, const AclItem *mod_aip,
int modechg, Oid ownerId, DropBehavior behavior);
extern Acl *aclnewowner(const Acl *old_acl, Oid oldOwnerId, Oid newOwnerId);
extern Acl *make_empty_acl(void);
extern Acl *aclcopy(const Acl *orig_acl);
extern Acl *aclconcat(const Acl *left_acl, const Acl *right_acl);
extern Acl *aclmerge(const Acl *left_acl, const Acl *right_acl, Oid ownerId);
extern void aclitemsort(Acl *acl);
extern bool aclequal(const Acl *left_acl, const Acl *right_acl);
extern AclMode aclmask(const Acl *acl, Oid roleid, Oid ownerId,
AclMode mask, AclMaskHow how);
extern int aclmembers(const Acl *acl, Oid **roleids);
extern bool has_privs_of_role(Oid member, Oid role);
extern bool is_member_of_role(Oid member, Oid role);
extern bool is_member_of_role_nosuper(Oid member, Oid role);
extern bool is_admin_of_role(Oid member, Oid role);
extern void check_is_member_of_role(Oid member, Oid role);
extern Oid get_role_oid(const char *rolename, bool missing_ok);
extern Oid get_role_oid_or_public(const char *rolename);
extern Oid get_rolespec_oid(const RoleSpec *role, bool missing_ok);
extern void check_rolespec_name(const RoleSpec *role, const char *detail_msg);
extern HeapTuple get_rolespec_tuple(const RoleSpec *role);
extern char *get_rolespec_name(const RoleSpec *role);
extern void select_best_grantor(Oid roleId, AclMode privileges,
const Acl *acl, Oid ownerId,
Oid *grantorId, AclMode *grantOptions);
extern void initialize_acl(void);
/*
* prototypes for functions in aclchk.c
*/
extern void ExecuteGrantStmt(GrantStmt *stmt);
extern void ExecAlterDefaultPrivilegesStmt(ParseState *pstate, AlterDefaultPrivilegesStmt *stmt);
extern void RemoveRoleFromObjectACL(Oid roleid, Oid classid, Oid objid);
extern void RemoveDefaultACLById(Oid defaclOid);
extern AclMode pg_attribute_aclmask(Oid table_oid, AttrNumber attnum,
Oid roleid, AclMode mask, AclMaskHow how);
extern AclMode pg_class_aclmask(Oid table_oid, Oid roleid,
AclMode mask, AclMaskHow how);
extern AclMode pg_database_aclmask(Oid db_oid, Oid roleid,
AclMode mask, AclMaskHow how);
extern AclMode pg_proc_aclmask(Oid proc_oid, Oid roleid,
AclMode mask, AclMaskHow how);
extern AclMode pg_language_aclmask(Oid lang_oid, Oid roleid,
AclMode mask, AclMaskHow how);
extern AclMode pg_largeobject_aclmask_snapshot(Oid lobj_oid, Oid roleid,
AclMode mask, AclMaskHow how, Snapshot snapshot);
extern AclMode pg_namespace_aclmask(Oid nsp_oid, Oid roleid,
AclMode mask, AclMaskHow how);
extern AclMode pg_tablespace_aclmask(Oid spc_oid, Oid roleid,
AclMode mask, AclMaskHow how);
extern AclMode pg_foreign_data_wrapper_aclmask(Oid fdw_oid, Oid roleid,
AclMode mask, AclMaskHow how);
extern AclMode pg_foreign_server_aclmask(Oid srv_oid, Oid roleid,
AclMode mask, AclMaskHow how);
extern AclMode pg_type_aclmask(Oid type_oid, Oid roleid,
AclMode mask, AclMaskHow how);
extern AclResult pg_attribute_aclcheck(Oid table_oid, AttrNumber attnum,
Oid roleid, AclMode mode);
extern AclResult pg_attribute_aclcheck_all(Oid table_oid, Oid roleid,
AclMode mode, AclMaskHow how);
extern AclResult pg_class_aclcheck(Oid table_oid, Oid roleid, AclMode mode);
extern AclResult pg_database_aclcheck(Oid db_oid, Oid roleid, AclMode mode);
extern AclResult pg_proc_aclcheck(Oid proc_oid, Oid roleid, AclMode mode);
extern AclResult pg_language_aclcheck(Oid lang_oid, Oid roleid, AclMode mode);
extern AclResult pg_largeobject_aclcheck_snapshot(Oid lang_oid, Oid roleid,
AclMode mode, Snapshot snapshot);
extern AclResult pg_namespace_aclcheck(Oid nsp_oid, Oid roleid, AclMode mode);
extern AclResult pg_tablespace_aclcheck(Oid spc_oid, Oid roleid, AclMode mode);
extern AclResult pg_foreign_data_wrapper_aclcheck(Oid fdw_oid, Oid roleid, AclMode mode);
extern AclResult pg_foreign_server_aclcheck(Oid srv_oid, Oid roleid, AclMode mode);
extern AclResult pg_type_aclcheck(Oid type_oid, Oid roleid, AclMode mode);
extern void aclcheck_error(AclResult aclerr, AclObjectKind objectkind,
const char *objectname);
extern void aclcheck_error_col(AclResult aclerr, AclObjectKind objectkind,
const char *objectname, const char *colname);
extern void aclcheck_error_type(AclResult aclerr, Oid typeOid);
extern void recordExtObjInitPriv(Oid objoid, Oid classoid);
extern void removeExtObjInitPriv(Oid objoid, Oid classoid);
/* ownercheck routines just return true (owner) or false (not) */
extern bool pg_class_ownercheck(Oid class_oid, Oid roleid);
extern bool pg_type_ownercheck(Oid type_oid, Oid roleid);
extern bool pg_oper_ownercheck(Oid oper_oid, Oid roleid);
extern bool pg_proc_ownercheck(Oid proc_oid, Oid roleid);
extern bool pg_language_ownercheck(Oid lan_oid, Oid roleid);
extern bool pg_largeobject_ownercheck(Oid lobj_oid, Oid roleid);
extern bool pg_namespace_ownercheck(Oid nsp_oid, Oid roleid);
extern bool pg_tablespace_ownercheck(Oid spc_oid, Oid roleid);
extern bool pg_opclass_ownercheck(Oid opc_oid, Oid roleid);
extern bool pg_opfamily_ownercheck(Oid opf_oid, Oid roleid);
extern bool pg_database_ownercheck(Oid db_oid, Oid roleid);
extern bool pg_collation_ownercheck(Oid coll_oid, Oid roleid);
extern bool pg_conversion_ownercheck(Oid conv_oid, Oid roleid);
extern bool pg_ts_dict_ownercheck(Oid dict_oid, Oid roleid);
extern bool pg_ts_config_ownercheck(Oid cfg_oid, Oid roleid);
extern bool pg_foreign_data_wrapper_ownercheck(Oid srv_oid, Oid roleid);
extern bool pg_foreign_server_ownercheck(Oid srv_oid, Oid roleid);
extern bool pg_event_trigger_ownercheck(Oid et_oid, Oid roleid);
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_ownercheck(Oid stat_oid, Oid roleid);
extern bool has_createrole_privilege(Oid roleid);
extern bool has_bypassrls_privilege(Oid roleid);
#endif /* ACL_H */