Make sure that usesuper is always accessed through superuser(), so that the
authorPeter Eisentraut <peter_e@gmx.net>
Thu, 11 Apr 2002 05:32:03 +0000 (05:32 +0000)
committerPeter Eisentraut <peter_e@gmx.net>
Thu, 11 Apr 2002 05:32:03 +0000 (05:32 +0000)
single-user escape path always works.

src/backend/catalog/aclchk.c
src/backend/commands/dbcommands.c
src/backend/utils/misc/superuser.c
src/include/catalog/pg_shadow.h

index 07f49c75ab2cffa3b4ac1c21a017730abb0c0d72..04f98449bdabb777c6721148833c1a51e11d5089 100644 (file)
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/catalog/aclchk.c,v 1.62 2002/04/09 20:35:46 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/catalog/aclchk.c,v 1.63 2002/04/11 05:32:02 petere Exp $
  *
  * NOTES
  *       See acl.h.
@@ -734,9 +734,6 @@ pg_class_aclcheck(Oid table_oid, Oid userid, AclMode mode)
 
        /*
         * Validate userid, find out if he is superuser
-        *
-        * We do not use superuser_arg() here because we also need to check
-        * usecatupd.
         */
        tuple = SearchSysCache(SHADOWSYSID,
                                                   ObjectIdGetDatum(userid),
@@ -744,11 +741,12 @@ pg_class_aclcheck(Oid table_oid, Oid userid, AclMode mode)
        if (!HeapTupleIsValid(tuple))
                elog(ERROR, "pg_class_aclcheck: invalid user id %u", userid);
 
-       usesuper = ((Form_pg_shadow) GETSTRUCT(tuple))->usesuper;
        usecatupd = ((Form_pg_shadow) GETSTRUCT(tuple))->usecatupd;
 
        ReleaseSysCache(tuple);
 
+       usesuper = superuser_arg(userid);
+
        /*
         * Now get the relation's tuple from pg_class
         */
index 9d40d6a11e328e858f301a4a79dda5ed3d7272a4..a6072be07ad8f11388e6bc86ef97c131ada7ca97 100644 (file)
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/commands/dbcommands.c,v 1.85 2002/03/06 06:09:32 momjian Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/commands/dbcommands.c,v 1.86 2002/04/11 05:32:03 petere Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -49,7 +49,7 @@ static bool get_db_info(const char *name, Oid *dbIdP, int4 *ownerIdP,
                        int *encodingP, bool *dbIsTemplateP, Oid *dbLastSysOidP,
                        TransactionId *dbVacuumXidP, TransactionId *dbFrozenXidP,
                        char *dbpath);
-static bool get_user_info(Oid use_sysid, bool *use_super, bool *use_createdb);
+static bool have_createdb_privilege(void);
 static char *resolve_alt_dbpath(const char *dbpath, Oid dboid);
 static bool remove_dbdirs(const char *real_loc, const char *altloc);
 
@@ -67,8 +67,6 @@ createdb(const char *dbname, const char *dbowner,
        char       *target_dir;
        char            src_loc[MAXPGPATH];
        char            buf[2 * MAXPGPATH + 100];
-       bool            use_super,
-                               use_createdb;
        Oid                     src_dboid;
        int4            src_owner;
        int                     src_encoding;
@@ -91,21 +89,17 @@ createdb(const char *dbname, const char *dbowner,
        else
                datdba = GetUserId();
 
-       /* check permission to create database */
-       if (!get_user_info(GetUserId(), &use_super, &use_createdb))
-               elog(ERROR, "current user name is invalid");
-
        if (datdba == (int32) GetUserId())
        {
                /* creating database for self: can be superuser or createdb */
-               if (!use_createdb && !use_super)
+               if (!superuser() && !have_createdb_privilege())
                        elog(ERROR, "CREATE DATABASE: permission denied");
        }
        else
        {
                /* creating database for someone else: must be superuser */
                /* note that the someone else need not have any permissions */
-               if (!use_super)
+               if (!superuser())
                        elog(ERROR, "CREATE DATABASE: permission denied");
        }
 
@@ -143,7 +137,7 @@ createdb(const char *dbname, const char *dbowner,
         */
        if (!src_istemplate)
        {
-               if (!use_super && GetUserId() != src_owner)
+               if (!superuser() && GetUserId() != src_owner )
                        elog(ERROR, "CREATE DATABASE: permission to copy \"%s\" denied",
                                 dbtemplate);
        }
@@ -332,7 +326,6 @@ dropdb(const char *dbname)
 {
        int4            db_owner;
        bool            db_istemplate;
-       bool            use_super;
        Oid                     db_id;
        char       *alt_loc;
        char       *nominal_loc;
@@ -350,9 +343,6 @@ dropdb(const char *dbname)
        if (IsTransactionBlock())
                elog(ERROR, "DROP DATABASE: may not be called in a transaction block");
 
-       if (!get_user_info(GetUserId(), &use_super, NULL))
-               elog(ERROR, "current user name is invalid");
-
        /*
         * Obtain exclusive lock on pg_database.  We need this to ensure that
         * no new backend starts up in the target database while we are
@@ -368,7 +358,7 @@ dropdb(const char *dbname)
                                         &db_istemplate, NULL, NULL, NULL, dbpath))
                elog(ERROR, "DROP DATABASE: database \"%s\" does not exist", dbname);
 
-       if (!use_super && GetUserId() != db_owner)
+       if (GetUserId() != db_owner && !superuser())
                elog(ERROR, "DROP DATABASE: permission denied");
 
        /*
@@ -605,25 +595,23 @@ get_db_info(const char *name, Oid *dbIdP, int4 *ownerIdP,
 }
 
 static bool
-get_user_info(Oid use_sysid, bool *use_super, bool *use_createdb)
+have_createdb_privilege(void)
 {
        HeapTuple       utup;
+       bool            retval;
 
        utup = SearchSysCache(SHADOWSYSID,
-                                                 ObjectIdGetDatum(use_sysid),
+                                                 ObjectIdGetDatum(GetUserId()),
                                                  0, 0, 0);
 
        if (!HeapTupleIsValid(utup))
-               return false;
-
-       if (use_super)
-               *use_super = ((Form_pg_shadow) GETSTRUCT(utup))->usesuper;
-       if (use_createdb)
-               *use_createdb = ((Form_pg_shadow) GETSTRUCT(utup))->usecreatedb;
+               retval = true;
+       else
+               retval = ((Form_pg_shadow) GETSTRUCT(utup))->usecreatedb;
 
        ReleaseSysCache(utup);
 
-       return true;
+       return retval;
 }
 
 
index f677d64fd3e3615d85b3745d6282625a62702120..4a3f3de1c540fe197362cb154ef678de6691c6a1 100644 (file)
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/utils/misc/superuser.c,v 1.20 2002/02/18 23:11:26 petere Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/utils/misc/superuser.c,v 1.21 2002/04/11 05:32:03 petere Exp $
  *
  *-------------------------------------------------------------------------
  */
 
 /*
  * The Postgres user running this command has Postgres superuser privileges
+ *
+ * All code should use either of these two functions to find out
+ * whether a given user is a superuser, rather than evaluating
+ * pg_shadow.usesuper directly, so that the escape hatch built in for
+ * the single-user case works.
  */
 bool
 superuser(void)
index 2e8d5b771c5d96a48d3be1d75d64e0ab468fb39c..fd372ae7bf47592395553b715a1b42756ce32656 100644 (file)
@@ -9,7 +9,7 @@
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: pg_shadow.h,v 1.18 2002/03/01 22:45:17 petere Exp $
+ * $Id: pg_shadow.h,v 1.19 2002/04/11 05:32:03 petere Exp $
  *
  * NOTES
  *       the genbki.sh script reads this file and generates .bki
@@ -35,7 +35,7 @@ CATALOG(pg_shadow) BOOTSTRAP BKI_WITHOUT_OIDS
        int4            usesysid;
        bool            usecreatedb;
        bool            usetrace;
-       bool            usesuper;
+       bool            usesuper;               /* read this field via superuser() only */
        bool            usecatupd;
        text            passwd;
        int4            valuntil;