-first pass at a reflection based secure input handler (using Java6 java.io.Console), fallsback to DefaultInputHandler if not available

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@540438 13f79535-47bb-0310-9956-ffa450edef68

src/main/org/apache/tools/ant/input/SecureInputHandler.java

@@ -0,0 +1,57 @@
+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one or more
+ *  contributor license agreements.  See the NOTICE file distributed with
+ *  this work for additional information regarding copyright ownership.
+ *  The ASF licenses this file to You under the Apache License, Version 2.0
+ *  (the "License"); you may not use this file except in compliance with
+ *  the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ */
+package org.apache.tools.ant.input;
+
+import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.util.ReflectUtil;
+
+/**
+ * Prompts and requests input.  May loop until a valid input has
+ * been entered. Doesn't echo input (requires Java6). If Java6 is not
+ * available, fallsback to the DefaultHandler (insecure).
+ * @since Ant 1.7.1
+ */
+public class SecureInputHandler extends DefaultInputHandler {
+
+    /**
+     * Default no-args constructor
+     */
+    public SecureInputHandler(){}
+
+    /**
+     * Handle the input
+     * @param request the request to handle
+     * @throws BuildException if not possible to read from console
+     */
+    public void handleInput(InputRequest request) throws BuildException {
+        String prompt = getPrompt(request);
+        try {
+            Class system = Class.forName("java.lang.System");
+            Object console = ReflectUtil.invokeStatic(system, "console");
+            do {
+                char[] input = (char[])ReflectUtil.invoke(console, "readPassword", String.class, prompt, Object[].class, (Object[]) null);
+                request.setInput(new String(input));
+                /* for security zero char array after retrieving value */
+                java.util.Arrays.fill(input, ' ');
+            } while (!request.isInputValid());
+        } catch (Exception e) {
+            /* Java6 not present use default handler */
+            super.handleInput(request);
+        }
+    }
+}