SERVER-20375 Constrain JS method thisv

This constrains universal access to wraptype methods by providing a
JS_ATTACH_JS_CONSTRAINED_METHOD() macro which allows for a list of types
that are allowed to call said method.

In this way we can lock down all methods without having to add uasserts
to each individual method body.

1 files changed, 22 insertions, 0 deletions

diff --git a/jstests/core/type5.js b/jstests/core/type5.js
new file mode 100644
index 00000000000..414af2be7eb
--- /dev/null
+++ b/jstests/core/type5.js
@@ -0,0 +1,22 @@
+(function(){
+    "use strict";
+
+    // This checks SERVER-20375 - Constrain JS method thisv
+    //
+    // Check to make sure we can't invoke methods on incorrect types, or on
+    // prototypes of objects that aren't intended to have methods invoked on
+    // them.
+
+    assert.throws(function(){
+        HexData(0, "aaaa").hex.apply({});
+    }, [], "invoke method on object of incorrect type");
+    assert.throws(function(){
+        var x = HexData(0, "aaaa");
+        x.hex.apply(10);
+    }, [], "invoke method on incorrect type");
+    assert.throws(function(){
+        var x = HexData(0, "aaaa");
+        x.hex.apply(x.__proto__);
+    }, [], "invoke method on prototype of correct type");
+
+})();