--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/sun/security/ssl/UnknownExtension.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2006, 2012, 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.security.ssl;
+
+import java.io.IOException;
+
+final class UnknownExtension extends HelloExtension {
+
+    private final byte[] data;
+
+    UnknownExtension(HandshakeInStream s, int len, ExtensionType type)
+            throws IOException {
+        super(type);
+        data = new byte[len];
+        // s.read() does not handle 0-length arrays.
+        if (len != 0) {
+            s.read(data);
+        }
+    }
+
+    @Override
+    int length() {
+        return 4 + data.length;
+    }
+
+    @Override
+    void send(HandshakeOutStream s) throws IOException {
+        s.putInt16(type.id);
+        s.putBytes16(data);
+    }
+
+    @Override
+    public String toString() {
+        return "Unsupported extension " + type + ", data: " +
+            Debug.toString(data);
+    }
+}