Add a security_barrier option for views.

When a view is marked as a security barrier, it will not be pulled up
into the containing query, and no quals will be pushed down into it,
so that no function or operator chosen by the user can be applied to
rows not exposed by the view.  Views not configured with this
option cannot provide robust row-level security, but will perform far
better.

Patch by KaiGai Kohei; original problem report by Heikki Linnakangas
(in October 2009!).  Review (in earlier versions) by Noah Misch and
others.  Design advice by Tom Lane and myself.  Further review and
cleanup by me.

1 files changed, 15 insertions, 2 deletions

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 100172fa4ac..7220e0e0ce9 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -67,6 +67,14 @@ static relopt_bool boolRelOpts[] =
 		},
 		true
 	},
+	{
+		{
+			"security_barrier",
+			"View acts as a row security barrier",
+			RELOPT_KIND_VIEW
+		},
+		false
+	},
 	/* list terminator */
 	{{NULL}}
 };
@@ -781,6 +789,7 @@ extractRelOptions(HeapTuple tuple, TupleDesc tupdesc, Oid amoptions)
 	{
 		case RELKIND_RELATION:
 		case RELKIND_TOASTVALUE:
+		case RELKIND_VIEW:
 		case RELKIND_UNCATALOGED:
 			options = heap_reloptions(classForm->relkind, datum, false);
 			break;
@@ -1139,7 +1148,9 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		{"autovacuum_vacuum_scale_factor", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, autovacuum) +offsetof(AutoVacOpts, vacuum_scale_factor)},
 		{"autovacuum_analyze_scale_factor", RELOPT_TYPE_REAL,
-		offsetof(StdRdOptions, autovacuum) +offsetof(AutoVacOpts, analyze_scale_factor)}
+		offsetof(StdRdOptions, autovacuum) +offsetof(AutoVacOpts, analyze_scale_factor)},
+		{"security_barrier", RELOPT_TYPE_BOOL,
+		offsetof(StdRdOptions, security_barrier)},
 	};
 
 	options = parseRelOptions(reloptions, validate, kind, &numoptions);
@@ -1159,7 +1170,7 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 }
 
 /*
- * Parse options for heaps and toast tables.
+ * Parse options for heaps, views and toast tables.
  */
 bytea *
 heap_reloptions(char relkind, Datum reloptions, bool validate)
@@ -1181,6 +1192,8 @@ heap_reloptions(char relkind, Datum reloptions, bool validate)
 			return (bytea *) rdopts;
 		case RELKIND_RELATION:
 			return default_reloptions(reloptions, validate, RELOPT_KIND_HEAP);
+		case RELKIND_VIEW:
+			return default_reloptions(reloptions, validate, RELOPT_KIND_VIEW);
 		default:
 			/* other relkinds are not supported */
 			return NULL;