granicus.if.org Git - postgresql/blob - src/backend/utils/misc/superuser.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * superuser.c
   4  *        The superuser() function.  Determines if user has superuser privilege.
   5  *        Also, a function to check for the owner (datdba) of a database.
   6  *
   7  *
   8  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
   9  * Portions Copyright (c) 1994, Regents of the University of California
  10  *
  11  *
  12  * IDENTIFICATION
  13  *        $Header: /cvsroot/pgsql/src/backend/utils/misc/superuser.c,v 1.20 2002/02/18 23:11:26 petere Exp $
  14  *
  15  *-------------------------------------------------------------------------
  16  */
  17 #include "postgres.h"
  18
  19 #include "access/heapam.h"
  20 #include "catalog/catname.h"
  21 #include "catalog/pg_database.h"
  22 #include "catalog/pg_shadow.h"
  23 #include "utils/syscache.h"
  24 #include "miscadmin.h"
  25 #include "utils/fmgroids.h"
  26
  27
  28 /*
  29  * The Postgres user running this command has Postgres superuser privileges
  30  */
  31 bool
  32 superuser(void)
  33 {
  34         return superuser_arg(GetUserId());
  35 }
  36
  37
  38 bool
  39 superuser_arg(Oid userid)
  40 {
  41         bool            result = false;
  42         HeapTuple       utup;
  43
  44         /* Special escape path in case you deleted all your users. */
  45         if (!IsUnderPostmaster && userid == BOOTSTRAP_USESYSID)
  46                 return true;
  47
  48         utup = SearchSysCache(SHADOWSYSID,
  49                                                   ObjectIdGetDatum(userid),
  50                                                   0, 0, 0);
  51         if (HeapTupleIsValid(utup))
  52         {
  53                 result = ((Form_pg_shadow) GETSTRUCT(utup))->usesuper;
  54                 ReleaseSysCache(utup);
  55         }
  56         return result;
  57 }
  58
  59
  60 /*
  61  * The Postgres user running this command is the owner of the specified
  62  * database.
  63  */
  64 bool
  65 is_dbadmin(Oid dbid)
  66 {
  67         Relation        pg_database;
  68         ScanKeyData entry[1];
  69         HeapScanDesc scan;
  70         HeapTuple       dbtuple;
  71         int32           dba;
  72
  73         /* There's no syscache for pg_database, so must look the hard way */
  74         pg_database = heap_openr(DatabaseRelationName, AccessShareLock);
  75         ScanKeyEntryInitialize(&entry[0], 0x0,
  76                                                    ObjectIdAttributeNumber, F_OIDEQ,
  77                                                    ObjectIdGetDatum(dbid));
  78         scan = heap_beginscan(pg_database, 0, SnapshotNow, 1, entry);
  79         dbtuple = heap_getnext(scan, 0);
  80         if (!HeapTupleIsValid(dbtuple))
  81                 elog(ERROR, "database %u does not exist", dbid);
  82         dba = ((Form_pg_database) GETSTRUCT(dbtuple))->datdba;
  83         heap_endscan(scan);
  84         heap_close(pg_database, AccessShareLock);
  85
  86         /* XXX some confusion about whether userids are OID or int4 ... */
  87         return (GetUserId() == (Oid) dba);
  88 }