--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/sun/security/provider/SecureRandom/StrongSeedReader.java	Thu Apr 11 21:03:24 2013 -0700
@@ -0,0 +1,81 @@
+ /*
+ * 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.
+ *
+ * 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.
+ */
+
+/**
+ * @test
+ * @bug 6425477
+ * @summary Better support for generation of high entropy random numbers
+ * @run main/othervm StrongSeedReader
+ */
+
+import java.io.*;
+import java.net.*;
+import java.security.SecureRandom;
+
+/**
+ * A simple test which takes into account knowledge about the underlying
+ * implementation. This may change if the implementations change.
+ *
+ * Create a new EGD file with known bytes, then set the EGD System property. The
+ * data read should be the same as what was written.
+ */
+public class StrongSeedReader {
+
+    public static void main(String[] args) throws Exception {
+        // Skip Windows, the SHA1PRNG uses CryptGenRandom.
+        if (System.getProperty("os.name", "unknown").startsWith("Windows")) {
+            return;
+        }
+
+        File file = null;
+        try {
+            file = new File(System.getProperty("java.io.tmpdir") +
+                    "StrongSeedReader.tmpdata");
+
+            // write a bunch of 0's to the file.
+            FileOutputStream fos = new FileOutputStream(file);
+            fos.write(new byte[2048]);
+
+            System.setProperty("java.security.egd", file.toURI().toString());
+            testSeed("NativePRNG");
+            testSeed("SHA1PRNG");
+        } finally {
+            if (file != null) {
+                file.delete();
+            }
+        }
+    }
+
+    private static void testSeed(String alg) throws Exception {
+        System.out.println("Testing: " + alg);
+        SecureRandom sr = SecureRandom.getInstance(alg);
+        byte[] ba = sr.generateSeed(20);
+
+        // We should get back a bunch of zeros from the file.
+        for (byte b : ba) {
+            if (b != 0) {
+                throw new Exception("Byte != 0");
+            }
+        }
+    }
+}