Add new USERLIMIT GUC source level so certain options can be disabled

or increased only by super-users.

This fixes problems caused by making certain variables SUSET for
security reasons.

src/backend/tcop/postgres.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.349 2003/07/04 16:41:21 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.350 2003/07/09 06:47:34 momjian Exp $
  *
  * NOTES
  *	  this is the "main" module of the postgres backend and
@@ -1943,7 +1943,7 @@ PostgresMain(int argc, char *argv[], const char *username)
 	bool		secure;
 	int			errs = 0;
 	int			debug_flag = 0;
-	GucContext	ctx;
+	GucContext	ctx, debug_context;
 	GucSource	gucsource;
 	char	   *tmp;
 	int			firstchar;
@@ -2018,7 +2018,7 @@ PostgresMain(int argc, char *argv[], const char *username)
 
 	/* all options are allowed until '-p' */
 	secure = true;
-	ctx = PGC_POSTMASTER;
+	ctx = debug_context = PGC_POSTMASTER;
 	gucsource = PGC_S_ARGV;		/* initial switches came from command line */
 
 	while ((flag = getopt(argc, argv, "A:B:c:CD:d:Eef:FiNOPo:p:S:st:v:W:x:-:")) != -1)
@@ -2055,25 +2055,34 @@ PostgresMain(int argc, char *argv[], const char *username)
 
 			case 'd':			/* debug level */
 				{
-					debug_flag = atoi(optarg);
-					/* Set server debugging level. */
-					if (atoi(optarg) != 0)
+					/*
+					 *	Client option can't decrease debug level.
+					 *	We have to do the test here because we group priv and client
+					 *	set GUC calls below, after we know the final debug value.
+					 */					   
+					if (ctx != PGC_BACKEND || atoi(optarg) > debug_flag)
 					{
-						char	   *debugstr = palloc(strlen("debug") + strlen(optarg) + 1);
-
-						sprintf(debugstr, "debug%s", optarg);
-						SetConfigOption("log_min_messages", debugstr, ctx, gucsource);
-						pfree(debugstr);
-
+						debug_flag = atoi(optarg);
+						debug_context = ctx;	/* save context for use below */
+						/* Set server debugging level. */
+						if (debug_flag != 0)
+						{
+							char	   *debugstr = palloc(strlen("debug") + strlen(optarg) + 1);
+	
+							sprintf(debugstr, "debug%s", optarg);
+							SetConfigOption("log_min_messages", debugstr, ctx, gucsource);
+							pfree(debugstr);
+	
+						}
+						else
+							/*
+							 * -d0 allows user to prevent postmaster debug
+							 * from propagating to backend.  It would be nice
+							 * to set it to the postgresql.conf value here.
+							 */
+							SetConfigOption("log_min_messages", "notice",
+											ctx, gucsource);
 					}
-					else
-						/*
-						 * -d0 allows user to prevent postmaster debug
-						 * from propagating to backend.  It would be nice
-						 * to set it to the postgresql.conf value here.
-						 */
-						SetConfigOption("log_min_messages", "notice",
-										ctx, gucsource);
 				}
 				break;
 
@@ -2323,20 +2332,19 @@ PostgresMain(int argc, char *argv[], const char *username)
 
 
 	/*
-	 * -d is not the same as setting
-	 * log_min_messages because it enables other
-	 * output options.
+	 * -d is not the same as setting log_min_messages because it enables
+	 * other output options.
 	 */
 	if (debug_flag >= 1)
-		SetConfigOption("log_connections", "true", ctx, gucsource);
+		SetConfigOption("log_connections", "true", debug_context, gucsource);
 	if (debug_flag >= 2)
-		SetConfigOption("log_statement", "true", ctx, gucsource);
+		SetConfigOption("log_statement", "true", debug_context, gucsource);
 	if (debug_flag >= 3)
-		SetConfigOption("debug_print_parse", "true", ctx, gucsource);
+		SetConfigOption("debug_print_parse", "true", debug_context, gucsource);
 	if (debug_flag >= 4)
-		SetConfigOption("debug_print_plan", "true", ctx, gucsource);
+		SetConfigOption("debug_print_plan", "true", debug_context, gucsource);
 	if (debug_flag >= 5)
-		SetConfigOption("debug_print_rewritten", "true", ctx, gucsource);
+		SetConfigOption("debug_print_rewritten", "true", debug_context, gucsource);
 
 	/*
 	 * Process any additional GUC variable settings passed in startup packet.
@@ -2548,7 +2556,7 @@ PostgresMain(int argc, char *argv[], const char *username)
 	if (!IsUnderPostmaster)
 	{
 		puts("\nPOSTGRES backend interactive interface ");
-		puts("$Revision: 1.349 $ $Date: 2003/07/04 16:41:21 $\n");
+		puts("$Revision: 1.350 $ $Date: 2003/07/09 06:47:34 $\n");
 	}
 
 	/*

src/backend/utils/misc/guc.c

@@ -10,7 +10,7 @@
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.134 2003/07/04 16:41:21 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.135 2003/07/09 06:47:34 momjian Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -449,7 +449,7 @@ static struct config_bool ConfigureNamesBool[] =
 		false, NULL, NULL
 	},
 	{
-		{"log_statement", PGC_SUSET, LOGGING_WHAT,
+		{"log_statement", PGC_USERLIMIT, LOGGING_WHAT,
 			gettext_noop("Causes each SQL statement to be logged"),
 			NULL
 		},
@@ -457,7 +457,7 @@ static struct config_bool ConfigureNamesBool[] =
 		false, NULL, NULL
 	},
 	{
-		{"log_duration", PGC_SUSET, LOGGING_WHAT,
+		{"log_duration", PGC_USERLIMIT, LOGGING_WHAT,
 			gettext_noop("Duration of every completed statement is logged"),
 			NULL
 		},
@@ -497,7 +497,7 @@ static struct config_bool ConfigureNamesBool[] =
 		false, NULL, NULL
 	},
 	{
-		{"log_parser_stats", PGC_SUSET, STATS_MONITORING,
+		{"log_parser_stats", PGC_USERLIMIT, STATS_MONITORING,
 			gettext_noop("Write parser performance stats to server log"),
 			NULL
 		},
@@ -505,7 +505,7 @@ static struct config_bool ConfigureNamesBool[] =
 		false, NULL, NULL
 	},
 	{
-		{"log_planner_stats", PGC_SUSET, STATS_MONITORING,
+		{"log_planner_stats", PGC_USERLIMIT, STATS_MONITORING,
 			gettext_noop("Write planner performance stats to server log"),
 			NULL
 		},
@@ -513,7 +513,7 @@ static struct config_bool ConfigureNamesBool[] =
 		false, NULL, NULL
 	},
 	{
-		{"log_executor_stats", PGC_SUSET, STATS_MONITORING,
+		{"log_executor_stats", PGC_USERLIMIT, STATS_MONITORING,
 			gettext_noop("Write executor performance stats to server log"),
 			NULL
 		},
@@ -521,7 +521,7 @@ static struct config_bool ConfigureNamesBool[] =
 		false, NULL, NULL
 	},
 	{
-		{"log_statement_stats", PGC_SUSET, STATS_MONITORING,
+		{"log_statement_stats", PGC_USERLIMIT, STATS_MONITORING,
 			gettext_noop("Write statement performance stats to server log"),
 			NULL
 		},
@@ -1107,7 +1107,7 @@ static struct config_int ConfigureNamesInt[] =
 	},
 
 	{
-		{"log_min_duration_statement", PGC_SUSET, LOGGING_WHEN,
+		{"log_min_duration_statement", PGC_USERLIMIT, LOGGING_WHEN,
 			gettext_noop("Min execution time (msec) above which statements will "
 						 "be logged"),
 			gettext_noop("The default is 0 (turning this feature off).")
@@ -1228,7 +1228,7 @@ static struct config_string ConfigureNamesString[] =
 	},
 
 	{
-		{"log_min_messages", PGC_SUSET, LOGGING_WHEN,
+		{"log_min_messages", PGC_USERLIMIT, LOGGING_WHEN,
 			gettext_noop("Controls which message levels logged"),
 			gettext_noop("Valid values are DEBUG5, DEBUG4, DEBUG3, DEBUG2, DEBUG1, "
 						 "INFO, NOTICE, WARNING, ERROR, LOG, FATAL, and PANIC. Each level "
@@ -1248,7 +1248,7 @@ static struct config_string ConfigureNamesString[] =
 	},
 
 	{
-		{"log_min_error_statement", PGC_SUSET, LOGGING_WHEN,
+		{"log_min_error_statement", PGC_USERLIMIT, LOGGING_WHEN,
 			gettext_noop("Controls whether the erroneous statement is logged"),
 			gettext_noop("All SQL statements that cause an error of the "
 						 "specified level, or a higher level, are logged")
@@ -1714,6 +1714,9 @@ InitializeGUCOptions(void)
 
 					Assert(conf->reset_val >= conf->min);
 					Assert(conf->reset_val <= conf->max);
+					/* Check to make sure we only have valid PGC_USERLIMITs */
+					Assert(conf->gen.context != PGC_USERLIMIT ||
+						   strcmp(conf->gen.name, "log_min_duration_statement") == 0);
 					if (conf->assign_hook)
 						if (!(*conf->assign_hook) (conf->reset_val, true, false))
 							fprintf(stderr, "Failed to initialize %s to %d\n",
@@ -1728,6 +1731,7 @@ InitializeGUCOptions(void)
 
 					Assert(conf->reset_val >= conf->min);
 					Assert(conf->reset_val <= conf->max);
+					Assert(conf->gen.context != PGC_USERLIMIT);
 					if (conf->assign_hook)
 						if (!(*conf->assign_hook) (conf->reset_val, true, false))
 							fprintf(stderr, "Failed to initialize %s to %g\n",
@@ -1741,6 +1745,11 @@ InitializeGUCOptions(void)
 					struct config_string *conf = (struct config_string *) gconf;
 					char	   *str;
 
+					/* Check to make sure we only have valid PGC_USERLIMITs */
+					Assert(conf->gen.context != PGC_USERLIMIT ||
+						   conf->assign_hook == assign_log_min_messages ||
+						   conf->assign_hook == assign_client_min_messages ||
+						   conf->assign_hook == assign_min_error_statement);
 					*conf->variable = NULL;
 					conf->reset_val = NULL;
 					conf->session_val = NULL;
@@ -1837,7 +1846,9 @@ ResetAllOptions(void)
 		struct config_generic *gconf = guc_variables[i];
 
 		/* Don't reset non-SET-able values */
-		if (gconf->context != PGC_SUSET && gconf->context != PGC_USERSET)
+		if (gconf->context != PGC_SUSET &&
+			gconf->context != PGC_USERLIMIT &&
+			gconf->context != PGC_USERSET)
 			continue;
 		/* Don't reset if special exclusion from RESET ALL */
 		if (gconf->flags & GUC_NO_RESET_ALL)
@@ -2286,6 +2297,7 @@ set_config_option(const char *name, const char *value,
 	int			elevel;
 	bool		interactive;
 	bool		makeDefault;
+	bool		DoIt_orig;
 
 	if (context == PGC_SIGHUP || source == PGC_S_DEFAULT)
 		elevel = DEBUG2;
@@ -2371,6 +2383,7 @@ set_config_option(const char *name, const char *value,
 				return false;
 			}
 			break;
+		case PGC_USERLIMIT:	/* USERLIMIT permissions checked below */
 		case PGC_USERSET:
 			/* always okay */
 			break;
@@ -2393,6 +2406,7 @@ set_config_option(const char *name, const char *value,
 	 * to set the reset/session values even if we can't set the variable
 	 * itself.
 	 */
+	DoIt_orig = DoIt;	/* we might have to reverse this later */
 	if (record->source > source)
 	{
 		if (DoIt && !makeDefault)
@@ -2422,6 +2436,24 @@ set_config_option(const char *name, const char *value,
 							 name);
 						return false;
 					}
+					/* Limit non-super user changes */
+					if (record->context == PGC_USERLIMIT &&
+						source > PGC_S_USERSTART &&
+						newval < conf->session_val &&
+						!superuser())
+					{
+						elog(elevel, "'%s': permission denied\n"
+								"Only super-users can set this value to false.",
+								name);
+						return false;
+					}
+					/* Allow admin to override non-super user setting */
+					if (record->context == PGC_USERLIMIT &&
+						source < PGC_S_USERSTART &&
+						record->session_source > PGC_S_USERSTART &&
+						newval > conf->session_val &&
+						!superuser())
+							DoIt = DoIt_orig;
 				}
 				else
 				{
@@ -2493,6 +2525,25 @@ set_config_option(const char *name, const char *value,
 							 name, newval, conf->min, conf->max);
 						return false;
 					}
+					/* Limit non-super user changes */
+					if (record->context == PGC_USERLIMIT &&
+						source > PGC_S_USERSTART &&
+						conf->session_val != 0 &&
+						newval > conf->session_val &&
+						!superuser())
+					{
+						elog(elevel, "'%s': permission denied\n"
+								"Only super-users can increase this value.",
+								name);
+						return false;
+					}
+					/* Allow admin to override non-super user setting */
+					if (record->context == PGC_USERLIMIT &&
+						source < PGC_S_USERSTART &&
+						record->session_source > PGC_S_USERSTART &&
+						newval < conf->session_val &&
+						!superuser())
+							DoIt = DoIt_orig;
 				}
 				else
 				{
@@ -2564,6 +2615,24 @@ set_config_option(const char *name, const char *value,
 							 name, newval, conf->min, conf->max);
 						return false;
 					}
+					/* Limit non-super user changes */
+					if (record->context == PGC_USERLIMIT &&
+						source > PGC_S_USERSTART &&
+						newval > conf->session_val &&
+						!superuser())
+					{
+						elog(elevel, "'%s': permission denied\n"
+								"Only super-users can increase this value.",
+								name);
+						return false;
+					}
+					/* Allow admin to override non-super user setting */
+					if (record->context == PGC_USERLIMIT &&
+						source < PGC_S_USERSTART &&
+						record->session_source > PGC_S_USERSTART &&
+						newval < conf->session_val &&
+						!superuser())
+							DoIt = DoIt_orig;
 				}
 				else
 				{
@@ -2628,6 +2697,32 @@ set_config_option(const char *name, const char *value,
 						elog(elevel, "out of memory");
 						return false;
 					}
+
+					if (*conf->variable)
+					{
+						int old_int_value, new_int_value;
+
+						/* Limit non-super user changes */
+						assign_msglvl(&old_int_value, conf->reset_val, true, interactive);
+						assign_msglvl(&new_int_value, newval, true, interactive);
+						if (record->context == PGC_USERLIMIT &&
+							source > PGC_S_USERSTART &&
+							new_int_value > old_int_value &&
+							!superuser())
+						{
+							elog(elevel, "'%s': permission denied\n"
+										"Only super-users can increase this value.",
+										name);
+							return false;
+						}
+						/* Allow admin to override non-super user setting */
+						if (record->context == PGC_USERLIMIT &&
+							source < PGC_S_USERSTART &&
+							record->session_source > PGC_S_USERSTART &&
+							newval < conf->session_val &&
+							!superuser())
+								DoIt = DoIt_orig;
+						}
 				}
 				else if (conf->reset_val)
 				{

src/include/utils/guc.h

@@ -7,7 +7,7 @@
  * Copyright 2000-2003 by PostgreSQL Global Development Group
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
- * $Id: guc.h,v 1.32 2003/06/11 18:01:14 momjian Exp $
+ * $Id: guc.h,v 1.33 2003/07/09 06:47:34 momjian Exp $
  *--------------------------------------------------------------------
  */
 #ifndef GUC_H
@@ -48,6 +48,9 @@
  * be set in the connection startup packet, because when it is processed
  * we don't yet know if the user is a superuser.
  *
+ * USERLIMIT options can only be manipulated in certain ways by
+ * non-super users.
+ *
  * USERSET options can be set by anyone any time.
  */
 typedef enum
@@ -57,6 +60,7 @@ typedef enum
 	PGC_SIGHUP,
 	PGC_BACKEND,
 	PGC_SUSET,
+	PGC_USERLIMIT,
 	PGC_USERSET
 } GucContext;
 
@@ -76,11 +80,16 @@ typedef enum
 	PGC_S_ENV_VAR = 1,			/* postmaster environment variable */
 	PGC_S_FILE = 2,				/* postgresql.conf */
 	PGC_S_ARGV = 3,				/* postmaster command line */
-	PGC_S_DATABASE = 4,			/* per-database setting */
-	PGC_S_USER = 5,				/* per-user setting */
-	PGC_S_CLIENT = 6,			/* from client connection request */
-	PGC_S_OVERRIDE = 7,			/* special case to forcibly set default */
-	PGC_S_SESSION = 8			/* SET command */
+	PGC_S_USERSTART=4,			/*
+								 *	Settings below are controlled by users.
+								 *	This is used by PGC_USERLIMT to prevent
+								 *	non-super users from changing certain settings.
+								 */
+	PGC_S_DATABASE = 5,			/* per-database setting */
+	PGC_S_USER = 6,				/* per-user setting */
+	PGC_S_CLIENT = 7,			/* from client connection request */
+	PGC_S_OVERRIDE = 8,			/* special case to forcibly set default */
+	PGC_S_SESSION = 9			/* SET command */
 } GucSource;