Add remote procedure execution via TDS protocol with RPC out validation for linked servers

contrib/babelfishpg_tds/error_mapping.txt

@@ -188,3 +188,7 @@ XX000 ERRCODE_INTERNAL_ERROR	"The table-valued parameter \"%s\" must be declared
 42P01 ERRCODE_UNDEFINED_TABLE	"FOR JSON AUTO requires at least one table for generating JSON objects. Use FOR JSON PATH or add a FROM clause with a table name."		SQL_ERROR_13600	16
 42P01 ERRCODE_FEATURE_NOT_SUPPORTED	"sub-select and values for json auto are not currently supported."		SQL_ERROR_13600	16
 
+HV004 ERRCODE_FDW_UNABLE_TO_CREATE_EXECUTION	"Could not execute statement on remote server '%s'."	SQL_ERROR_7215	16	"Could not execute statement on remote server"
+HV000 ERRCODE_FDW_ERROR	"Server '%s' is not configured for RPC OUT."	SQL_ERROR_7412	16	"is not configured for RPC OUT"
+HV000 ERRCODE_FDW_ERROR	"Could not find server '%s' in sys.servers."	SQL_ERROR_7202	11	"Could not find server"
+

contrib/babelfishpg_tsql/sql/linked_servers_tsql.sql

@@ -1,7 +1,8 @@
 CREATE TABLE sys.babelfish_server_options (
 	servername sys.SYSNAME NOT NULL PRIMARY KEY COLLATE "C",
 	query_timeout INT,
-	connect_timeout INT
+	connect_timeout INT,
+	rpc_out BOOLEAN DEFAULT FALSE
 );
 GRANT SELECT ON sys.babelfish_server_options TO PUBLIC;
 

contrib/babelfishpg_tsql/sql/sys_views.sql

@@ -3528,7 +3528,7 @@ SELECT
   CAST(s.query_timeout as int) AS query_timeout,
   CAST(1 as sys.bit) AS is_linked,
   CAST(0 as sys.bit) AS is_remote_login_enabled,
-  CAST(0 as sys.bit) AS is_rpc_out_enabled,
+  CAST(COALESCE(s.rpc_out, false) as sys.bit) AS is_rpc_out_enabled,
   CAST(1 as sys.bit) AS is_data_access_enabled,
   CAST(0 as sys.bit) AS is_collation_compatible,
   CAST(1 as sys.bit) AS uses_remote_collation,

contrib/babelfishpg_tsql/sql/upgrades/babelfishpg_tsql--5.4.0--5.5.0.sql

@@ -1675,6 +1675,54 @@ BEGIN
 END;
 $$ 
 LANGUAGE plpgsql IMMUTABLE STRICT;
+-- Add rpc_out column to babelfish_server_options for remote procedure execution feature
+ALTER TABLE sys.babelfish_server_options ADD COLUMN IF NOT EXISTS rpc_out BOOLEAN DEFAULT FALSE;
+
+-- Recreate sys.servers view to include rpc_out column
+CREATE OR REPLACE VIEW sys.servers
+AS
+SELECT
+  CAST(f.oid as int) AS server_id,
+  CAST(f.srvname as sys.sysname) AS name,
+  CAST('' as sys.sysname) AS product,
+  CAST('tds_fdw' as sys.sysname) AS provider,
+  CAST((select PG_CATALOG.string_agg(
+                  case
+                  when option like 'servername=%%' then substring(option, 12)
+                  else NULL
+                  end, ',')
+          from unnest(f.srvoptions) as option) as sys.nvarchar(4000)) AS data_source,
+  CAST(NULL as sys.nvarchar(4000)) AS location,
+  CAST(NULL as sys.nvarchar(4000)) AS provider_string,
+  CAST((select PG_CATALOG.string_agg(
+                  case
+                  when option like 'database=%%' then substring(option, 10)
+                  else NULL
+                  end, ',')
+          from unnest(f.srvoptions) as option) as sys.sysname) AS catalog,
+  CAST(s.connect_timeout as int) AS connect_timeout,
+  CAST(s.query_timeout as int) AS query_timeout,
+  CAST(1 as sys.bit) AS is_linked,
+  CAST(0 as sys.bit) AS is_remote_login_enabled,
+  CAST(COALESCE(s.rpc_out, false) as sys.bit) AS is_rpc_out_enabled,
+  CAST(1 as sys.bit) AS is_data_access_enabled,
+  CAST(0 as sys.bit) AS is_collation_compatible,
+  CAST(1 as sys.bit) AS uses_remote_collation,
+  CAST(NULL as sys.sysname) AS collation_name,
+  CAST(0 as sys.bit) AS lazy_schema_validation,
+  CAST(0 as sys.bit) AS is_system,
+  CAST(0 as sys.bit) AS is_publisher,
+  CAST(0 as sys.bit) AS is_subscriber,
+  CAST(0 as sys.bit) AS is_distributor,
+  CAST(0 as sys.bit) AS is_nonsql_subscriber,
+  CAST(1 as sys.bit) AS is_remote_proc_transaction_promotion_enabled,
+  CAST(NULL as sys.datetime) AS modify_date,
+  CAST(0 as sys.bit) AS is_rda_server
+FROM pg_foreign_server AS f
+LEFT JOIN pg_foreign_data_wrapper AS w ON f.srvfdw = w.oid
+LEFT JOIN sys.babelfish_server_options AS s on f.srvname = s.servername
+WHERE w.fdwname = 'tds_fdw';
+GRANT SELECT ON sys.servers TO PUBLIC;
 
 -- Drops the temporary procedure used by the upgrade script.
 -- Please have this be one of the last statements executed in this upgrade script.

contrib/babelfishpg_tsql/src/catalog.c

@@ -330,8 +330,8 @@ initTsqlSyscache()
 bool
 IsPLtsqlExtendedCatalog(Oid relationId)
 {
-	/* Skip during Babelfish restore */
-	if (!babelfish_dump_restore && (relationId == sysdatabases_oid ||
+	/* Skip during Babelfish restore or extension creation/upgrade */
+	if (!babelfish_dump_restore && !creating_extension && (relationId == sysdatabases_oid ||
 		relationId == bbf_function_ext_oid || relationId == namespace_ext_oid ||
 		relationId == bbf_authid_login_ext_oid || relationId == bbf_authid_user_ext_oid ||
 		relationId == bbf_view_def_oid || relationId == bbf_servers_def_oid ||
@@ -1423,6 +1423,42 @@ get_timeout_from_server_name(char *servername, int attnum)
 	return timeout;
 }
 
+bool
+get_rpc_out_option(char *servername)
+{
+	Relation	bbf_servers_def_rel;
+	HeapTuple	tuple;
+	ScanKeyData	key;
+	TableScanDesc	scan;
+	bool		rpc_out_enabled = false;  /* Default to disabled */
+
+	bbf_servers_def_rel = table_open(get_bbf_servers_def_oid(),
+										 AccessShareLock);
+
+	ScanKeyInit(&key,
+				Anum_bbf_servers_def_servername,
+				BTEqualStrategyNumber, F_TEXTEQ,
+				CStringGetTextDatum(servername));
+
+	scan = table_beginscan_catalog(bbf_servers_def_rel, 1, &key);
+
+	tuple = heap_getnext(scan, ForwardScanDirection);
+	if (HeapTupleIsValid(tuple))
+	{
+		bool	isNull;
+		rpc_out_enabled = DatumGetBool(heap_getattr(tuple, 
+													 Anum_bbf_servers_def_rpc_out,
+													 RelationGetDescr(bbf_servers_def_rel), 
+													 &isNull));
+		if (isNull)
+			rpc_out_enabled = false;  /* Default if NULL */
+	}
+
+	table_endscan(scan);
+	table_close(bbf_servers_def_rel, AccessShareLock);
+	return rpc_out_enabled;
+}
+
 void
 clean_up_bbf_server_def()
 {
@@ -6490,4 +6526,4 @@ bbf_check_member_has_direct_priv_to_grant_role(Oid member, Oid role)
 
 	ReleaseSysCacheList(memlist);
 	return false;
-}
+}

contrib/babelfishpg_tsql/src/catalog.h

@@ -243,13 +243,15 @@ typedef FormData_bbf_view_def * Form_bbf_view_def;
 #define Anum_bbf_servers_def_servername 1
 #define Anum_bbf_servers_def_query_timeout 2
 #define Anum_bbf_servers_def_connect_timeout 3
-#define BBF_SERVERS_DEF_NUM_COLS 3
+#define Anum_bbf_servers_def_rpc_out 4
+#define BBF_SERVERS_DEF_NUM_COLS 4
 extern Oid	bbf_servers_def_oid;
 extern Oid	bbf_servers_def_idx_oid;
 
 extern Oid get_bbf_servers_def_oid(void);
 extern Oid get_bbf_servers_def_idx_oid(void);
 extern int get_timeout_from_server_name(char *servername, int attnum);
+extern bool get_rpc_out_option(char *servername);
 extern int get_server_id_from_server_name(char *servername);
 extern void clean_up_bbf_server_def(void);
 
@@ -258,6 +260,7 @@ typedef struct FormData_bbf_servers_def
 	text		servername;
 	int32		query_timeout;
 	int32		connect_timeout;
+	bool		rpc_out;
 } FormData_bbf_servers_def;
 
 typedef FormData_bbf_servers_def *Form_bbf_servers_def;

contrib/babelfishpg_tsql/src/guc.c

@@ -47,6 +47,7 @@ char	   *pltsql_language = NULL;
 char	   *pltsql_psql_logical_babelfish_db_name = NULL;
 int			pltsql_lock_timeout = -1;
 bool		pltsql_enable_linked_servers = true;
+bool		pltsql_enable_remote_proc_exec = true;
 bool		pltsql_enable_ownership_chaining = true;
 bool		pltsql_allow_windows_login = true;
 bool		pltsql_allow_fulltext_parser = false;
@@ -1257,6 +1258,15 @@ define_custom_variables(void)
 							 GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_AUTO_FILE,
 							 NULL, NULL, NULL);
 
+	DefineCustomBoolVariable("babelfishpg_tsql.enable_remote_proc_exec",
+							 gettext_noop("Enables remote procedure execution via four-part names (EXEC server.db.schema.proc)"),
+							 NULL,
+							 &pltsql_enable_remote_proc_exec,
+							 true,
+							 PGC_SUSET,
+							 GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_AUTO_FILE,
+							 NULL, NULL, NULL);
+
 	/* GUC to enable/disable the ownership chaining feature, by default enabled */
 	DefineCustomBoolVariable("babelfishpg_tsql.enable_ownership_chaining",
 							 gettext_noop("Enables ownership chaining"),

contrib/babelfishpg_tsql/src/guc.h

@@ -19,6 +19,7 @@ extern bool pltsql_fmtonly;
 extern bool pltsql_enable_create_alter_view_from_pg;
 extern bool	pltsql_enable_alter_owner_from_pg;
 extern bool pltsql_enable_linked_servers;
+extern bool pltsql_enable_remote_proc_exec;
 extern bool pltsql_enable_ownership_chaining;
 extern bool pltsql_allow_windows_login;
 extern bool pltsql_allow_fulltext_parser;