pg_hba_rules_12.patch

diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml
index 524180e..4129b3a 100644
--- a/doc/src/sgml/catalogs.sgml
+++ b/doc/src/sgml/catalogs.sgml
@@ -7804,6 +7804,11 @@
      </row>
 
      <row>
+      <entry><link linkend="view-pg-hba-rules"><structname>pg_hba_rules</structname></link></entry>
+      <entry>summary of client authentication configuration file contents</entry>
+     </row>
+
+     <row>
       <entry><link linkend="view-pg-group"><structname>pg_group</structname></link></entry>
       <entry>groups of database users</entry>
      </row>
@@ -8352,6 +8357,125 @@
 
 </sect1>
 
+ <sect1 id="view-pg-hba-rules">
+  <title><structname>pg_hba_rules</structname></title>
+
+  <indexterm zone="view-pg-hba-rules">
+   <primary>pg_hba_rules</primary>
+  </indexterm>
+
+  <para>
+   The view <structname>pg_hba_rules</structname> provides a summary of
+   the contents of the client authentication configuration file.  A row 
+   appears in this view for each entry appearing in the file, with annotations
+   indicating whether the rule could be applied successfully.
+  </para>
+
+  <table>
+   <title><structname>pg_hba_rules</> Columns</title>
+
+  <tgroup cols="3">
+   <thead>
+    <row>
+     <entry>Name</entry>
+     <entry>Type</entry>
+     <entry>Description</entry>
+    </row>
+   </thead>
+   <tbody>
+    <row>
+     <entry><structfield>line_number</structfield></entry>
+     <entry><structfield>integer</structfield></entry>
+     <entry>
+      Line number of the client authentication rule in
+      pg_hba.conf file
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>type</structfield></entry>
+     <entry><structfield>text</structfield></entry>
+     <entry>Type of connection</entry>
+    </row>
+    <row>
+     <entry><structfield>database</structfield></entry>
+     <entry><structfield>text[]</structfield></entry>
+     <entry>List of database names</entry>
+    </row>
+    <row>
+     <entry><structfield>user_name</structfield></entry>
+     <entry><structfield>text[]</structfield></entry>
+     <entry>List of user names</entry>
+    </row>
+    <row>
+     <entry><structfield>address</structfield></entry>
+     <entry><structfield>text</structfield></entry>
+     <entry>
+      Address specifies the set of hosts the record matches.
+      It can be a host name, or it is made up of an IP address
+      or keywords such as (<literal>all</literal>, 
+      <literal>samehost</literal> and <literal>samenet</literal>).
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>netmask</structfield></entry>
+     <entry><structfield>text</structfield></entry>
+     <entry>Address mask if exist</entry>
+    </row>
+    <row>
+     <entry><structfield>auth_method</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>Authentication method</entry>
+    </row>
+    <row>
+     <entry><structfield>options</structfield></entry>
+     <entry><type>text[]</type></entry>
+     <entry>Configuration options set for authentication method</entry>
+    </row>
+    <row>
+     <entry><structfield>error</structfield></entry>
+     <entry><structfield>text</structfield></entry>
+     <entry>
+      If not null, an error message indicates why this
+      rule could not be loaded.
+     </entry>
+    </row>
+   </tbody>
+  </tgroup>
+  </table>
+
+  <para>
+   <structfield>error</structfield> field, if not NULL, describes problem
+   in the rule on the line <structfield>line_number</structfield>.
+   Following is the sample output of the view.
+  </para>
+  
+<programlisting>
+SELECT line_number, type, database, user_name, auth_method FROM pg_hba_rules;
+</programlisting>
+
+<screen>
+ line_number | type  |  database  | user_name  |   address    | auth_method 
+-------------+-------+------------+------------+--------------+-------------
+          84 | local | {all}      | {all}      |              | trust
+          86 | host  | {sameuser} | {postgres} | all          | trust
+          88 | host  | {postgres} | {postgres} | ::1          | trust
+         111 | host  | {all}      | {all}      | 127.0.0.1    | trust
+         121 | host  | {all}      | {all}      | localhost    | trust
+         128 | host  | {postgres} | {all}      | samenet      | ident
+         134 | host  | {postgres} | {all}      | samehost     | md5
+         140 | host  | {db1,db2}  | {all}      | .example.com | md5
+         149 | host  | {test}     | {test}     | 192.168.54.1 | reject
+         159 | host  | {all}      | {+support} | 192.168.0.0  | ident
+         169 | local | {sameuser} | {all}      |              | md5
+(11 rows)
+</screen>
+
+  <para>
+   See <xref linkend="client-authentication"> for more information about the various
+   ways to change client authentication configuration.
+  </para>
+ </sect1>
+
  <sect1 id="view-pg-group">
   <title><structname>pg_group</structname></title>
 
diff --git a/doc/src/sgml/client-auth.sgml b/doc/src/sgml/client-auth.sgml
index dda5891..f20486c 100644
--- a/doc/src/sgml/client-auth.sgml
+++ b/doc/src/sgml/client-auth.sgml
@@ -54,6 +54,13 @@
   database user names and OS user names.
  </para>
 
+ <para>
+  The system view
+  <link linkend="view-pg-hba-rules"><structname>pg_hba_rules</structname></link>
+  can be helpful for pre-testing changes to the client authentication configuration file, or for
+  diagnosing problems if loading of file did not have the desired effects.
+ </para>
+
  <sect1 id="auth-pg-hba-conf">
   <title>The <filename>pg_hba.conf</filename> File</title>
 
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 4dfedf8..d920a72 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -459,6 +459,12 @@ CREATE VIEW pg_file_settings AS
 REVOKE ALL on pg_file_settings FROM PUBLIC;
 REVOKE EXECUTE ON FUNCTION pg_show_all_file_settings() FROM PUBLIC;
 
+CREATE VIEW pg_hba_rules AS
+   SELECT * FROM pg_hba_rules() AS A;
+
+REVOKE ALL on pg_hba_rules FROM PUBLIC;
+REVOKE EXECUTE ON FUNCTION pg_hba_rules() FROM PUBLIC;
+
 CREATE VIEW pg_timezone_abbrevs AS
     SELECT * FROM pg_timezone_abbrevs();
 
diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c
index 07f046f..b6d9bbb 100644
--- a/src/backend/libpq/hba.c
+++ b/src/backend/libpq/hba.c
@@ -25,15 +25,22 @@
 #include <arpa/inet.h>
 #include <unistd.h>
 
+#include "access/htup_details.h"
+#include "catalog/objectaddress.h"
 #include "catalog/pg_collation.h"
+#include "catalog/pg_type.h"
 #include "common/ip.h"
+#include "funcapi.h"
 #include "libpq/ifaddr.h"
 #include "libpq/libpq.h"
+#include "miscadmin.h"
 #include "postmaster/postmaster.h"
 #include "regex/regex.h"
 #include "replication/walsender.h"
 #include "storage/fd.h"
+#include "storage/ipc.h"
 #include "utils/acl.h"
+#include "utils/builtins.h"
 #include "utils/guc.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"
@@ -76,6 +83,30 @@ typedef struct HbaToken
 } HbaToken;
 
 /*
+ * The following character array represents the names of the authentication
+ * methods that are supported by the PostgreSQL.
+ *
+ * NOTE: This structure should be in sync with the UserAuth enum.
+ */
+static char *UserAuthName[] =
+{
+	"reject",
+	"implict reject",			/* Not possible to set by user */
+	"trust",
+	"ident",
+	"password",
+	"md5",
+	"gss",
+	"sspi",
+	"pam",
+	"bsd",
+	"ldap",
+	"cert",
+	"radius",
+	"peer"
+};
+
+/*
  * pre-parsed content of HBA config file: list of HbaLine structs.
  * parsed_hba_context is the memory context where it lives.
  */
@@ -99,7 +130,11 @@ static MemoryContext tokenize_file(const char *filename, FILE *file,
 static List *tokenize_inc_file(List *tokens, const char *outer_filename,
 				  const char *inc_filename);
 static bool parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline,
-				   int line_num);
+				   int line_num, int level, char **err_msg);
+static Datum gethba_options(HbaLine *hba);
+static void fill_hba_line(TupleDesc tupdesc, Tuplestorestate *tuple_store,
+			  int lineno, HbaLine *hba, const char *err_msg);
+static void fill_hba(TupleDesc tupdesc, Tuplestorestate *tuple_store);
 
 /*
  * isblank() exists in the ISO C99 spec, but it's not very portable yet,
@@ -748,13 +783,15 @@ check_same_host_or_net(SockAddr *raddr, IPCompareMethod method)
  *						 reporting error if it's not.
  */
 #define INVALID_AUTH_OPTION(optname, validmethods) do {\
-	ereport(LOG, \
+	ereport(level, \
 			(errcode(ERRCODE_CONFIG_FILE_ERROR), \
 			 /* translator: the second %s is a list of auth methods */ \
 			 errmsg("authentication option \"%s\" is only valid for authentication methods %s", \
 					optname, _(validmethods)), \
 			 errcontext("line %d of configuration file \"%s\"", \
 					line_num, HbaFileName))); \
+	*err_msg = psprintf("authentication option \"%s\" is only valid for authentication methods %s", \
+						optname, validmethods); \
 	return false; \
 } while (0);
 
@@ -765,12 +802,14 @@ check_same_host_or_net(SockAddr *raddr, IPCompareMethod method)
 
 #define MANDATORY_AUTH_ARG(argvar, argname, authname) do {\
 	if (argvar == NULL) {\
-		ereport(LOG, \
+		ereport(level, \
 				(errcode(ERRCODE_CONFIG_FILE_ERROR), \
 				 errmsg("authentication method \"%s\" requires argument \"%s\" to be set", \
 						authname, argname), \
 				 errcontext("line %d of configuration file \"%s\"", \
 						line_num, HbaFileName))); \
+		*err_msg = psprintf("authentication method \"%s\" requires argument \"%s\" to be set", \
+							authname, argname); \
 		return NULL; \
 	} \
 } while (0);
@@ -818,7 +857,8 @@ check_same_host_or_net(SockAddr *raddr, IPCompareMethod method)
  * NULL.
  */
 static HbaLine *
-parse_hba_line(List *line, int line_num, char *raw_line)
+parse_hba_line(List *line, int line_num, char *raw_line,
+			   int level, char **err_msg)
 {
 	char	   *str;
 	struct addrinfo *gai_result;
@@ -841,12 +881,13 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 	tokens = lfirst(field);
 	if (tokens->length > 1)
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("multiple values specified for connection type"),
 				 errhint("Specify exactly one connection type per line."),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = "multiple values specified for connection type";
 		return NULL;
 	}
 	token = linitial(tokens);
@@ -855,11 +896,12 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 #ifdef HAVE_UNIX_SOCKETS
 		parsedline->conntype = ctLocal;
 #else
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("local connections are not supported by this build"),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = "local connections are not supported by this build";
 		return NULL;
 #endif
 	}
@@ -874,19 +916,23 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 			/* Log a warning if SSL support is not active */
 #ifdef USE_SSL
 			if (!EnableSSL)
-				ereport(LOG,
+			{
+				ereport(level,
 						(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				errmsg("hostssl record cannot match because SSL is disabled"),
 						 errhint("Set ssl = on in postgresql.conf."),
 						 errcontext("line %d of configuration file \"%s\"",
 									line_num, HbaFileName)));
+				*err_msg = "hostssl record cannot match because SSL is disabled";
+			}
 #else
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 					 errmsg("hostssl record cannot match because SSL is not supported by this build"),
 			  errhint("Compile with --with-openssl to use SSL connections."),
 					 errcontext("line %d of configuration file \"%s\"",
 								line_num, HbaFileName)));
+			*err_msg = "hostssl record cannot match because SSL is not supported by this build";
 #endif
 		}
 		else if (token->string[4] == 'n')		/* "hostnossl" */
@@ -901,12 +947,14 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 	}							/* record type */
 	else
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("invalid connection type \"%s\"",
 						token->string),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = psprintf("invalid connection type \"%s\"", token->string);
+
 		return NULL;
 	}
 
@@ -914,11 +962,12 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 	field = lnext(field);
 	if (!field)
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("end-of-line before database specification"),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = "end-of-line before database specification";
 		return NULL;
 	}
 	parsedline->databases = NIL;
@@ -933,11 +982,12 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 	field = lnext(field);
 	if (!field)
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("end-of-line before role specification"),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = "end-of-line before role specification";
 		return NULL;
 	}
 	parsedline->roles = NIL;
@@ -954,22 +1004,24 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 		field = lnext(field);
 		if (!field)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 					 errmsg("end-of-line before IP address specification"),
 					 errcontext("line %d of configuration file \"%s\"",
 								line_num, HbaFileName)));
+			*err_msg = "end-of-line before IP address specification";
 			return NULL;
 		}
 		tokens = lfirst(field);
 		if (tokens->length > 1)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 					 errmsg("multiple values specified for host address"),
 					 errhint("Specify one address range per line."),
 					 errcontext("line %d of configuration file \"%s\"",
 								line_num, HbaFileName)));
+			*err_msg = "multiple values specified for host address";
 			return NULL;
 		}
 		token = linitial(tokens);
@@ -1019,12 +1071,14 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 				parsedline->hostname = str;
 			else
 			{
-				ereport(LOG,
+				ereport(level,
 						(errcode(ERRCODE_CONFIG_FILE_ERROR),
 						 errmsg("invalid IP address \"%s\": %s",
 								str, gai_strerror(ret)),
 						 errcontext("line %d of configuration file \"%s\"",
 									line_num, HbaFileName)));
+				*err_msg = psprintf("invalid IP address \"%s\": %s",
+									str, gai_strerror(ret));
 				if (gai_result)
 					pg_freeaddrinfo_all(hints.ai_family, gai_result);
 				return NULL;
@@ -1037,24 +1091,28 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 			{
 				if (parsedline->hostname)
 				{
-					ereport(LOG,
+					ereport(level,
 							(errcode(ERRCODE_CONFIG_FILE_ERROR),
 							 errmsg("specifying both host name and CIDR mask is invalid: \"%s\"",
 									token->string),
 						   errcontext("line %d of configuration file \"%s\"",
 									  line_num, HbaFileName)));
+					*err_msg = psprintf("specifying both host name and CIDR mask is invalid: \"%s\"",
+										token->string);
 					return NULL;
 				}
 
 				if (pg_sockaddr_cidr_mask(&parsedline->mask, cidr_slash + 1,
 										  parsedline->addr.ss_family) < 0)
 				{
-					ereport(LOG,
+					ereport(level,
 							(errcode(ERRCODE_CONFIG_FILE_ERROR),
 							 errmsg("invalid CIDR mask in address \"%s\"",
 									token->string),
 						   errcontext("line %d of configuration file \"%s\"",
 									  line_num, HbaFileName)));
+					*err_msg = psprintf("invalid CIDR mask in address \"%s\"",
+										token->string);
 					return NULL;
 				}
 				pfree(str);
@@ -1066,22 +1124,24 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 				field = lnext(field);
 				if (!field)
 				{
-					ereport(LOG,
+					ereport(level,
 							(errcode(ERRCODE_CONFIG_FILE_ERROR),
 						  errmsg("end-of-line before netmask specification"),
 							 errhint("Specify an address range in CIDR notation, or provide a separate netmask."),
 						   errcontext("line %d of configuration file \"%s\"",
 									  line_num, HbaFileName)));
+					*err_msg = "end-of-line before netmask specification";
 					return NULL;
 				}
 				tokens = lfirst(field);
 				if (tokens->length > 1)
 				{
-					ereport(LOG,
+					ereport(level,
 							(errcode(ERRCODE_CONFIG_FILE_ERROR),
 							 errmsg("multiple values specified for netmask"),
 						   errcontext("line %d of configuration file \"%s\"",
 									  line_num, HbaFileName)));
+					*err_msg = "multiple values specified for netmask";
 					return NULL;
 				}
 				token = linitial(tokens);
@@ -1090,12 +1150,14 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 										 &hints, &gai_result);
 				if (ret || !gai_result)
 				{
-					ereport(LOG,
+					ereport(level,
 							(errcode(ERRCODE_CONFIG_FILE_ERROR),
 							 errmsg("invalid IP mask \"%s\": %s",
 									token->string, gai_strerror(ret)),
 						   errcontext("line %d of configuration file \"%s\"",
 									  line_num, HbaFileName)));
+					*err_msg = psprintf("invalid IP mask \"%s\": %s",
+										token->string, gai_strerror(ret));
 					if (gai_result)
 						pg_freeaddrinfo_all(hints.ai_family, gai_result);
 					return NULL;
@@ -1107,11 +1169,12 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 
 				if (parsedline->addr.ss_family != parsedline->mask.ss_family)
 				{
-					ereport(LOG,
+					ereport(level,
 							(errcode(ERRCODE_CONFIG_FILE_ERROR),
 							 errmsg("IP address and mask do not match"),
 						   errcontext("line %d of configuration file \"%s\"",
 									  line_num, HbaFileName)));
+					*err_msg = "IP address and mask do not match";
 					return NULL;
 				}
 			}
@@ -1122,22 +1185,24 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 	field = lnext(field);
 	if (!field)
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("end-of-line before authentication method"),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = "end-of-line before authentication method";
 		return NULL;
 	}
 	tokens = lfirst(field);
 	if (tokens->length > 1)
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("multiple values specified for authentication type"),
 				 errhint("Specify exactly one authentication type per line."),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = "multiple values specified for authentication type";
 		return NULL;
 	}
 	token = linitial(tokens);
@@ -1169,11 +1234,12 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 	{
 		if (Db_user_namespace)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 					 errmsg("MD5 authentication is not supported when \"db_user_namespace\" is enabled"),
 					 errcontext("line %d of configuration file \"%s\"",
 								line_num, HbaFileName)));
+			*err_msg = "MD5 authentication is not supported when \"db_user_namespace\" is enabled";
 			return NULL;
 		}
 		parsedline->auth_method = uaMD5;
@@ -1206,23 +1272,27 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 		parsedline->auth_method = uaRADIUS;
 	else
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("invalid authentication method \"%s\"",
 						token->string),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = psprintf("invalid authentication method \"%s\"",
+							token->string);
 		return NULL;
 	}
 
 	if (unsupauth)
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("invalid authentication method \"%s\": not supported by this build",
 						token->string),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = psprintf("invalid authentication method \"%s\": not supported by this build",
+							token->string);
 		return NULL;
 	}
 
@@ -1238,22 +1308,24 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 	if (parsedline->conntype == ctLocal &&
 		parsedline->auth_method == uaGSS)
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 		   errmsg("gssapi authentication is not supported on local sockets"),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = "gssapi authentication is not supported on local sockets";
 		return NULL;
 	}
 
 	if (parsedline->conntype != ctLocal &&
 		parsedline->auth_method == uaPeer)
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 			errmsg("peer authentication is only supported on local sockets"),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = "peer authentication is only supported on local sockets";
 		return NULL;
 	}
 
@@ -1266,11 +1338,12 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 	if (parsedline->conntype != ctHostSSL &&
 		parsedline->auth_method == uaCert)
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("cert authentication is only supported on hostssl connections"),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = "cert authentication is only supported on hostssl connections";
 		return NULL;
 	}
 
@@ -1315,16 +1388,18 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 				/*
 				 * Got something that's not a name=value pair.
 				 */
-				ereport(LOG,
+				ereport(level,
 						(errcode(ERRCODE_CONFIG_FILE_ERROR),
 						 errmsg("authentication option not in name=value format: %s", token->string),
 						 errcontext("line %d of configuration file \"%s\"",
 									line_num, HbaFileName)));
+				*err_msg = psprintf("authentication option not in name=value format: %s",
+									token->string);
 				return NULL;
 			}
 
 			*val++ = '\0';		/* str now holds "name", val holds "value" */
-			if (!parse_hba_auth_opt(str, val, parsedline, line_num))
+			if (!parse_hba_auth_opt(str, val, parsedline, line_num, level, err_msg))
 				/* parse_hba_auth_opt already logged the error message */
 				return NULL;
 			pfree(str);
@@ -1352,21 +1427,23 @@ parse_hba_line(List *line, int line_num, char *raw_line)
 				parsedline->ldapbindpasswd ||
 				parsedline->ldapsearchattribute)
 			{
-				ereport(LOG,
+				ereport(level,
 						(errcode(ERRCODE_CONFIG_FILE_ERROR),
 						 errmsg("cannot use ldapbasedn, ldapbinddn, ldapbindpasswd, ldapsearchattribute, or ldapurl together with ldapprefix"),
 						 errcontext("line %d of configuration file \"%s\"",
 									line_num, HbaFileName)));
+				*err_msg = "cannot use ldapbasedn, ldapbinddn, ldapbindpasswd, ldapsearchattribute, or ldapurl together with ldapprefix";
 				return NULL;
 			}
 		}
 		else if (!parsedline->ldapbasedn)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 					 errmsg("authentication method \"ldap\" requires argument \"ldapbasedn\", \"ldapprefix\", or \"ldapsuffix\" to be set"),
 					 errcontext("line %d of configuration file \"%s\"",
 								line_num, HbaFileName)));
+			*err_msg = "authentication method \"ldap\" requires argument \"ldapbasedn\", \"ldapprefix\", or \"ldapsuffix\" to be set";
 			return NULL;
 		}
 	}
@@ -1394,7 +1471,7 @@ parse_hba_line(List *line, int line_num, char *raw_line)
  * encounter an error.
  */
 static bool
-parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num)
+parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num, int level, char **err_msg)
 {
 #ifdef USE_LDAP
 	hbaline->ldapscope = LDAP_SCOPE_SUBTREE;
@@ -1414,11 +1491,12 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num)
 	{
 		if (hbaline->conntype != ctHostSSL)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 			errmsg("clientcert can only be configured for \"hostssl\" rows"),
 					 errcontext("line %d of configuration file \"%s\"",
 								line_num, HbaFileName)));
+			*err_msg = "clientcert can only be configured for \"hostssl\" rows";
 			return false;
 		}
 		if (strcmp(val, "1") == 0)
@@ -1429,11 +1507,12 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num)
 		{
 			if (hbaline->auth_method == uaCert)
 			{
-				ereport(LOG,
+				ereport(level,
 						(errcode(ERRCODE_CONFIG_FILE_ERROR),
 						 errmsg("clientcert can not be set to 0 when using \"cert\" authentication"),
 						 errcontext("line %d of configuration file \"%s\"",
 									line_num, HbaFileName)));
+				*err_msg = "clientcert can not be set to 0 when using \"cert\" authentication";
 				return false;
 			}
 			hbaline->clientcert = false;
@@ -1465,18 +1544,23 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num)
 		rc = ldap_url_parse(val, &urldata);
 		if (rc != LDAP_SUCCESS)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 					 errmsg("could not parse LDAP URL \"%s\": %s", val, ldap_err2string(rc))));
+			*err_msg = psprintf("could not parse LDAP URL \"%s\": %s",
+								val, ldap_err2string(rc));
 			return false;
 		}
 
 		if (strcmp(urldata->lud_scheme, "ldap") != 0)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 			errmsg("unsupported LDAP URL scheme: %s", urldata->lud_scheme)));
+			*err_msg = psprintf("unsupported LDAP URL scheme: %s",
+								urldata->lud_scheme);
 			ldap_free_urldesc(urldata);
+
 			return false;
 		}
 
@@ -1489,17 +1573,19 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num)
 		hbaline->ldapscope = urldata->lud_scope;
 		if (urldata->lud_filter)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 					 errmsg("filters not supported in LDAP URLs")));
+			*err_msg = "filters not supported in LDAP URLs";
 			ldap_free_urldesc(urldata);
 			return false;
 		}
 		ldap_free_urldesc(urldata);
 #else							/* not OpenLDAP */
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("LDAP URLs not supported on this platform")));
+		*err_msg = "LDAP URLs not supported on this platform";
 #endif   /* not OpenLDAP */
 	}
 	else if (strcmp(name, "ldaptls") == 0)
@@ -1521,11 +1607,12 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num)
 		hbaline->ldapport = atoi(val);
 		if (hbaline->ldapport == 0)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 					 errmsg("invalid LDAP port number: \"%s\"", val),
 					 errcontext("line %d of configuration file \"%s\"",
 								line_num, HbaFileName)));
+			*err_msg = psprintf("invalid LDAP port number: \"%s\"", val);
 			return false;
 		}
 	}
@@ -1609,12 +1696,14 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num)
 		ret = pg_getaddrinfo_all(val, NULL, &hints, &gai_result);
 		if (ret || !gai_result)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 					 errmsg("could not translate RADIUS server name \"%s\" to address: %s",
 							val, gai_strerror(ret)),
 					 errcontext("line %d of configuration file \"%s\"",
 								line_num, HbaFileName)));
+			*err_msg = psprintf("could not translate RADIUS server name \"%s\" to address: %s",
+								val, gai_strerror(ret));
 			if (gai_result)
 				pg_freeaddrinfo_all(hints.ai_family, gai_result);
 			return false;
@@ -1628,11 +1717,12 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num)
 		hbaline->radiusport = atoi(val);
 		if (hbaline->radiusport == 0)
 		{
-			ereport(LOG,
+			ereport(level,
 					(errcode(ERRCODE_CONFIG_FILE_ERROR),
 					 errmsg("invalid RADIUS port number: \"%s\"", val),
 					 errcontext("line %d of configuration file \"%s\"",
 								line_num, HbaFileName)));
+			*err_msg = psprintf("invalid RADIUS port number: \"%s\"", val);
 			return false;
 		}
 	}
@@ -1648,12 +1738,14 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num)
 	}
 	else
 	{
-		ereport(LOG,
+		ereport(level,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("unrecognized authentication option name: \"%s\"",
 						name),
 				 errcontext("line %d of configuration file \"%s\"",
 							line_num, HbaFileName)));
+		*err_msg = psprintf("unrecognized authentication option name: \"%s\"",
+							name);
 		return false;
 	}
 	return true;
@@ -1802,8 +1894,9 @@ load_hba(void)
 	forthree(line, hba_lines, line_num, hba_line_nums, raw_line, hba_raw_lines)
 	{
 		HbaLine    *newline;
+		char	   *err_msg = NULL;
 
-		if ((newline = parse_hba_line(lfirst(line), lfirst_int(line_num), lfirst(raw_line))) == NULL)
+		if ((newline = parse_hba_line(lfirst(line), lfirst_int(line_num), lfirst(raw_line), LOG, &err_msg)) == NULL)
 		{
 			/*
 			 * Parse error in the file, so indicate there's a problem.  NB: a
@@ -2255,3 +2348,358 @@ hba_getauthmethod(hbaPort *port)
 {
 	check_hba(port);
 }
+
+/*
+ * The Macro that specifies the maximum number of authentication options
+ * that are possible with any given authentication method that is supported.
+ * Currently LDAP supports 10, The macro value is well above the most any
+ * method needs
+ */
+#define MAX_HBA_OPTIONS 12
+
+static Datum
+gethba_options(HbaLine *hba)
+{
+	int			noptions;
+	Datum		options[MAX_HBA_OPTIONS];
+
+	noptions = 0;
+
+	if (hba->auth_method == uaGSS || hba->auth_method == uaSSPI)
+	{
+		if (hba->include_realm)
+			options[noptions++] = CStringGetTextDatum("include_realm=true");
+
+		if (hba->krb_realm)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("krb_realm=%s", hba->krb_realm));
+	}
+
+	if (hba->usermap)
+		options[noptions++] = CStringGetTextDatum(psprintf("map=%s", hba->usermap));
+
+	if (hba->clientcert)
+		options[noptions++] = CStringGetTextDatum("clientcert=true");
+
+	if (hba->pamservice)
+		options[noptions++] = CStringGetTextDatum(psprintf("pamservice=%s", hba->pamservice));
+
+	if (hba->auth_method == uaLDAP)
+	{
+		if (hba->ldapserver)
+			options[noptions++] = CStringGetTextDatum(psprintf("ldapserver=%s", hba->ldapserver));
+
+		if (hba->ldapport)
+			options[noptions++] = CStringGetTextDatum(psprintf("ldapport=%d", hba->ldapport));
+
+		if (hba->ldaptls)
+			options[noptions++] = CStringGetTextDatum("ldaptls=true");
+
+		if (hba->ldapprefix)
+			options[noptions++] = CStringGetTextDatum(psprintf("ldapprefix=%s", hba->ldapprefix));
+
+		if (hba->ldapsuffix)
+			options[noptions++] = CStringGetTextDatum(psprintf("ldapsuffix=%s", hba->ldapsuffix));
+
+		if (hba->ldapbasedn)
+			options[noptions++] = CStringGetTextDatum(psprintf("ldapbasedn=%s", hba->ldapbasedn));
+
+		if (hba->ldapbinddn)
+			options[noptions++] = CStringGetTextDatum(psprintf("ldapbinddn=%s", hba->ldapbinddn));
+
+		if (hba->ldapbindpasswd)
+			options[noptions++] = CStringGetTextDatum(psprintf("ldapbindpasswd=%s", hba->ldapbindpasswd));
+
+		if (hba->ldapsearchattribute)
+			options[noptions++] = CStringGetTextDatum(psprintf("ldapsearchattribute=%s", hba->ldapsearchattribute));
+
+		if (hba->ldapscope)
+			options[noptions++] = CStringGetTextDatum(psprintf("ldapscope=%d", hba->ldapscope));
+	}
+
+	if (hba->auth_method == uaRADIUS)
+	{
+		if (hba->radiusserver)
+			options[noptions++] = CStringGetTextDatum(psprintf("radiusserver=%s", hba->radiusserver));
+
+		if (hba->radiussecret)
+			options[noptions++] = CStringGetTextDatum(psprintf("radiussecret=%s", hba->radiussecret));
+
+		if (hba->radiusidentifier)
+			options[noptions++] = CStringGetTextDatum(psprintf("radiusidentifier=%s", hba->radiusidentifier));
+
+		if (hba->radiusport)
+			options[noptions++] = CStringGetTextDatum(psprintf("radiusport=%d", hba->radiusport));
+	}
+
+	Assert(noptions <= MAX_HBA_OPTIONS);
+	if (noptions)
+		return PointerGetDatum(
+				construct_array(options, noptions, TEXTOID, -1, false, 'i'));
+	return PointerGetDatum(NULL);
+}
+
+#define NUM_PG_HBA_RULES_ATTS	 9
+
+static void
+fill_hba_line(TupleDesc tupdesc, Tuplestorestate *tuple_store, int lineno, HbaLine *hba, const char *err_msg)
+{
+	Datum		values[NUM_PG_HBA_RULES_ATTS];
+	bool		nulls[NUM_PG_HBA_RULES_ATTS];
+	ListCell   *dbcell;
+	char		buffer[NI_MAXHOST];
+	HeapTuple	tuple;
+	int			index;
+	Datum		options;
+
+	index = 0;
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
+
+	/* line_number */
+	values[index] = Int32GetDatum(lineno);
+
+	if (err_msg)
+	{
+		/* set all remaining columns as NULL, except error column */
+		memset(&nulls[1], true, (NUM_PG_HBA_RULES_ATTS - 2));
+
+		/* error */
+		values[NUM_PG_HBA_RULES_ATTS - 1] = CStringGetTextDatum(err_msg);
+	}
+	else
+	{
+		/* type */
+		index++;
+		switch (hba->conntype)
+		{
+			case ctLocal:
+				values[index] = CStringGetTextDatum("local");
+				break;
+			case ctHost:
+				values[index] = CStringGetTextDatum("host");
+				break;
+			case ctHostSSL:
+				values[index] = CStringGetTextDatum("hostssl");
+				break;
+			case ctHostNoSSL:
+				values[index] = CStringGetTextDatum("hostnossl");
+				break;
+		}
+
+		/* database */
+		index++;
+		if (hba->databases)
+		{
+			List	   *names = NULL;
+			HbaToken   *tok;
+
+			foreach(dbcell, hba->databases)
+			{
+				tok = lfirst(dbcell);
+				names = lappend(names, tok->string);
+			}
+
+			/* database */
+			Assert(names != NULL);
+			values[index] = PointerGetDatum(strlist_to_textarray(names));
+		}
+		else
+			nulls[index] = true;
+
+		/* user */
+		index++;
+		if (hba->roles)
+		{
+			List	   *roles = NULL;
+			HbaToken   *tok;
+
+			foreach(dbcell, hba->roles)
+			{
+				tok = lfirst(dbcell);
+				roles = lappend(roles, tok->string);
+			}
+
+			/* user */
+			Assert(roles != NULL);
+			values[index] = PointerGetDatum(strlist_to_textarray(roles));
+		}
+		else
+			nulls[index] = true;
+
+
+		/* address */
+		index++;
+		switch (hba->ip_cmp_method)
+		{
+			case ipCmpMask:
+				if (hba->hostname)
+				{
+					values[index] = CStringGetTextDatum(hba->hostname);
+					nulls[++index] = true;
+				}
+				else
+				{
+					if (pg_getnameinfo_all(&hba->addr, sizeof(struct sockaddr_storage),
+										   buffer, sizeof(buffer),
+										   NULL, 0,
+										   NI_NUMERICHOST) == 0)
+					{
+						clean_ipv6_addr(hba->addr.ss_family, buffer);
+						values[index] = CStringGetTextDatum(buffer);
+					}
+					else
+						nulls[index] = true;
+
+					/* netmask */
+					if (pg_getnameinfo_all(&hba->mask, sizeof(struct sockaddr_storage),
+										   buffer, sizeof(buffer),
+										   NULL, 0,
+										   NI_NUMERICHOST) == 0)
+					{
+						clean_ipv6_addr(hba->mask.ss_family, buffer);
+						values[++index] = CStringGetTextDatum(buffer);
+					}
+					else
+						nulls[++index] = true;
+				}
+				break;
+			case ipCmpAll:
+				values[index] = CStringGetTextDatum("all");
+				nulls[++index] = true;
+				break;
+			case ipCmpSameHost:
+				values[index] = CStringGetTextDatum("samehost");
+				nulls[++index] = true;
+				break;
+			case ipCmpSameNet:
+				values[index] = CStringGetTextDatum("samenet");
+				nulls[++index] = true;
+				break;
+		}
+
+		/* auth_method */
+		index++;
+		values[index] = CStringGetTextDatum(UserAuthName[hba->auth_method]);
+
+		/* options */
+		index++;
+		options = gethba_options(hba);
+		if (options)
+			values[index] = PointerGetDatum(options);
+		else
+			nulls[index] = true;
+
+		/* error */
+		index++;
+		nulls[index] = true;
+	}
+
+	tuple = heap_form_tuple(tupdesc, values, nulls);
+	tuplestore_puttuple(tuple_store, tuple);
+
+	return;
+}
+
+/*
+ * Read the config file and fill the HbaLine records for the view.
+ */
+static void
+fill_hba(TupleDesc tupdesc, Tuplestorestate *tuple_store)
+{
+	FILE	   *file;
+	List	   *hba_lines = NIL;
+	List	   *hba_line_nums = NIL;
+	List	   *hba_raw_lines = NIL;
+	ListCell   *line,
+			   *line_num,
+			   *raw_line;
+	MemoryContext linecxt;
+	MemoryContext hbacxt;
+	MemoryContext oldcxt;
+
+	file = AllocateFile(HbaFileName, "r");
+	if (file == NULL)
+	{
+		ereport(ERROR,
+				(errcode_for_file_access(),
+				 errmsg("could not open configuration file \"%s\": %m",
+						HbaFileName)));
+		return;
+	}
+
+	linecxt = tokenize_file(HbaFileName, file, &hba_lines, &hba_line_nums, &hba_raw_lines);
+	FreeFile(file);
+
+	/* Now parse all the lines */
+	hbacxt = AllocSetContextCreate(CurrentMemoryContext,
+								   "hba parser context",
+								   ALLOCSET_SMALL_SIZES);
+	oldcxt = MemoryContextSwitchTo(hbacxt);
+	forthree(line, hba_lines, line_num, hba_line_nums, raw_line, hba_raw_lines)
+	{
+		HbaLine    *newline;
+		int			lineno = lfirst_int(line_num);
+		char	   *err_msg = NULL;
+
+		newline = parse_hba_line(lfirst(line), lineno, lfirst(raw_line), DEBUG3, &err_msg);
+		fill_hba_line(tupdesc, tuple_store, lineno, newline, err_msg);
+	}
+
+	/* Free tokenizer memory */
+	MemoryContextDelete(linecxt);
+	MemoryContextSwitchTo(oldcxt);
+	MemoryContextDelete(hbacxt);
+}
+
+/*
+ * SQL-accessible SRF to return all the settings from the pg_hba.conf
+ * file.
+ */
+Datum
+hba_rules(PG_FUNCTION_ARGS)
+{
+	Tuplestorestate *tuple_store;
+	TupleDesc	tupdesc;
+	MemoryContext old_cxt;
+	ReturnSetInfo *rsi;
+
+	/*
+	 * We must use the Materialize mode to be safe against HBA file reloads
+	 * while the cursor is open. It's also more efficient than having to look
+	 * up our current position in the parsed list every time.
+	 */
+	rsi = (ReturnSetInfo *) fcinfo->resultinfo;
+
+	/* Check to see if caller supports us returning a tuplestore */
+	if (rsi == NULL || !IsA(rsi, ReturnSetInfo))
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("set-valued function called in context that cannot accept a set")));
+	if (!(rsi->allowedModes & SFRM_Materialize))
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("materialize mode required, but it is not " \
+						"allowed in this context")));
+
+	rsi->returnMode = SFRM_Materialize;
+
+	/* Build a tuple descriptor for our result type */
+	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
+		elog(ERROR, "return type must be a row type");
+
+	/* Build tuplestore to hold the result rows */
+	old_cxt = MemoryContextSwitchTo(rsi->econtext->ecxt_per_query_memory);
+
+	tuple_store =
+		tuplestore_begin_heap(rsi->allowedModes & SFRM_Materialize_Random,
+							  false, work_mem);
+	rsi->setDesc = tupdesc;
+	rsi->setResult = tuple_store;
+
+	MemoryContextSwitchTo(old_cxt);
+
+	fill_hba(tupdesc, tuple_store);
+
+	PG_RETURN_NULL();
+}
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index c1f492b..6ccbdec 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -3076,6 +3076,8 @@ DATA(insert OID = 2084 (  pg_show_all_settings	PGNSP PGUID 12 1 1000 0 0 f f f f
 DESCR("SHOW ALL as a function");
 DATA(insert OID = 3329 (  pg_show_all_file_settings PGNSP PGUID 12 1 1000 0 0 f f f f t t v s 0 0 2249 "" "{25,23,23,25,25,16,25}" "{o,o,o,o,o,o,o}" "{sourcefile,sourceline,seqno,name,setting,applied,error}" _null_ _null_ show_all_file_settings _null_ _null_ _null_ ));
 DESCR("show config file settings");
+DATA(insert OID = 3401 (  pg_hba_rules PGNSP PGUID 12 1 1000 0 0 f f f f t t v s 0 0 2249 "" "{23,25,1009,1009,25,25,25,1009,25}" "{o,o,o,o,o,o,o,o,o}" "{line_number,type,database,user_name,address,netmask,auth_method,options,error}" _null_ _null_ hba_rules _null_ _null_ _null_ ));
+DESCR("show pg_hba config rules");
 DATA(insert OID = 1371 (  pg_lock_status   PGNSP PGUID 12 1 1000 0 0 f f f f t t v s 0 0 2249 "" "{25,26,26,23,21,25,28,26,26,21,25,23,25,16,16}" "{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{locktype,database,relation,page,tuple,virtualxid,transactionid,classid,objid,objsubid,virtualtransaction,pid,mode,granted,fastpath}" _null_ _null_ pg_lock_status _null_ _null_ _null_ ));
 DESCR("view system lock information");
 DATA(insert OID = 2561 (  pg_blocking_pids PGNSP PGUID 12 1 0 0 0 f f f f t f v s 1 0 1007 "23" _null_ _null_ _null_ _null_ _null_ pg_blocking_pids _null_ _null_ _null_ ));
diff --git a/src/include/libpq/hba.h b/src/include/libpq/hba.h
index dc7d257..c936308 100644
--- a/src/include/libpq/hba.h
+++ b/src/include/libpq/hba.h
@@ -15,11 +15,17 @@
 #include "nodes/pg_list.h"
 #include "regex/regex.h"
 
-
+/*
+ * The following enum represents the authentication methods that
+ * are supported by PostgreSQL.
+ *
+ * NOTE: Any additions in this enum must update the UserAuthName array to be
+ * in sync.
+ */
 typedef enum UserAuth
 {
 	uaReject,
-	uaImplicitReject,
+	uaImplicitReject,			/* Not user visibile option */
 	uaTrust,
 	uaIdent,
 	uaPassword,
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 60abcad..de7860a 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1338,6 +1338,16 @@ pg_group| SELECT pg_authid.rolname AS groname,
           WHERE (pg_auth_members.roleid = pg_authid.oid)) AS grolist
    FROM pg_authid
   WHERE (NOT pg_authid.rolcanlogin);
+pg_hba_rules| SELECT a.line_number,
+    a.type,
+    a.database,
+    a.user_name,
+    a.address,
+    a.netmask,
+    a.auth_method,
+    a.options,
+    a.error
+   FROM pg_hba_rules() a(line_number, type, database, user_name, address, netmask, auth_method, options, error);
 pg_indexes| SELECT n.nspname AS schemaname,
     c.relname AS tablename,
     i.relname AS indexname,