8010117: Annotate jdk caller sensitive methods with @sun.reflect.CallerSensitive

Reviewed-by: jrose, alanb, twisti

2 files changed, 69 insertions, 10 deletions

diff --git a/src/share/classes/sun/reflect/CallerSensitive.java b/src/share/classes/sun/reflect/CallerSensitive.java
new file mode 100644
index 000000000..19e47cdd5
--- /dev/null
+++ b/src/share/classes/sun/reflect/CallerSensitive.java
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package sun.reflect;
+
+import java.lang.annotation.*;
+import static java.lang.annotation.ElementType.*;
+
+/**
+ * A method annotated @CallerSensitive is sensitive to its calling class,
+ * via {@link sun.reflect.Reflection#getCallerClass Reflection.getCallerClass},
+ * or via some equivalent.
+ *
+ * @author John R. Rose
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target({CONSTRUCTOR, METHOD})
+public @interface CallerSensitive {
+}
diff --git a/src/share/classes/sun/reflect/Reflection.java b/src/share/classes/sun/reflect/Reflection.java
index fb5598269..274705fc2 100644
--- a/src/share/classes/sun/reflect/Reflection.java
+++ b/src/share/classes/sun/reflect/Reflection.java
@@ -51,16 +51,11 @@ public class Reflection {
         methodFilterMap = new HashMap<>();
     }
 
-    /** Returns the class of the method <code>realFramesToSkip</code>
-        frames up the stack (zero-based), ignoring frames associated
-        with java.lang.reflect.Method.invoke() and its implementation.
-        The first frame is that associated with this method, so
-        <code>getCallerClass(0)</code> returns the Class object for
-        sun.reflect.Reflection. Frames associated with
-        java.lang.reflect.Method.invoke() and its implementation are
-        completely ignored and do not count toward the number of "real"
-        frames skipped. */
-    public static native Class<?> getCallerClass(int realFramesToSkip);
+    /** Returns the class of the caller of the method calling this method,
+        ignoring frames associated with java.lang.reflect.Method.invoke()
+        and its implementation. */
+    @CallerSensitive
+    public static native Class<?> getCallerClass();
 
     /** Retrieves the access flags written to the class file. For
         inner classes these flags may differ from those returned by
@@ -321,4 +316,27 @@ public class Reflection {
         }
         return newMembers;
     }
+
+    /**
+     * Tests if the given method is caller-sensitive and the declaring class
+     * is defined by either the bootstrap class loader or extension class loader.
+     */
+    public static boolean isCallerSensitive(Method m) {
+        final ClassLoader loader = m.getDeclaringClass().getClassLoader();
+        if (sun.misc.VM.isSystemDomainLoader(loader) || isExtClassLoader(loader))  {
+            return m.isAnnotationPresent(CallerSensitive.class);
+        }
+        return false;
+    }
+
+    private static boolean isExtClassLoader(ClassLoader loader) {
+        ClassLoader cl = ClassLoader.getSystemClassLoader();
+        while (cl != null) {
+            if (cl.getParent() == null && cl == loader) {
+                return true;
+            }
+            cl = cl.getParent();
+        }
+        return false;
+    }
 }