1 /*

     2  * Copyright 2003-2006 Sun Microsystems, Inc.  All Rights Reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Sun designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Sun in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    22  * CA 95054 USA or visit www.sun.com if you need additional information or

    23  * have any questions.

    24  */

    25 

    26 package sun.security.util;

    27 

    28 import java.io.*;

    29 import java.nio.*;

    30 import java.nio.charset.*;

    31 import java.util.Arrays;

    32 

    33 /**

    34  * A utility class for reading passwords

    35  *

    36  */

    37 public class Password {

    38     /** Reads user password from given input stream. */

    39     public static char[] readPassword(InputStream in) throws IOException {

    40 

    41         char[] consoleEntered = null;

    42         byte[] consoleBytes = null;

    43 

    44         try {

    45             // Use the new java.io.Console class

    46             Console con = null;

    47             if (in == System.in && ((con = System.console()) != null)) {

    48                 consoleEntered = con.readPassword();

    49                 // readPassword returns "" if you just print ENTER,

    50                 // to be compatible with old Password class, change to null

    51                 if (consoleEntered != null && consoleEntered.length == 0) {

    52                     return null;

    53                 }

    54                 consoleBytes = convertToBytes(consoleEntered);

    55                 in = new ByteArrayInputStream(consoleBytes);

    56             }

    57 

    58             // Rest of the lines still necessary for KeyStoreLoginModule

    59             // and when there is no console.

    60 

    61             char[] lineBuffer;

    62             char[] buf;

    63             int i;

    64 

    65             buf = lineBuffer = new char[128];

    66 

    67             int room = buf.length;

    68             int offset = 0;

    69             int c;

    70 

    71             boolean done = false;

    72             while (!done) {

    73                 switch (c = in.read()) {

    74                   case -1:

    75                   case '\n':

    76                       done = true;

    77                       break;

    78 

    79                   case '\r':

    80                     int c2 = in.read();

    81                     if ((c2 != '\n') && (c2 != -1)) {

    82                         if (!(in instanceof PushbackInputStream)) {

    83                             in = new PushbackInputStream(in);

    84                         }

    85                         ((PushbackInputStream)in).unread(c2);

    86                     } else {

    87                         done = true;

    88                         break;

    89                     }

    90 

    91                   default:

    92                     if (--room < 0) {

    93                         buf = new char[offset + 128];

    94                         room = buf.length - offset - 1;

    95                         System.arraycopy(lineBuffer, 0, buf, 0, offset);

    96                         Arrays.fill(lineBuffer, ' ');

    97                         lineBuffer = buf;

    98                     }

    99                     buf[offset++] = (char) c;

   100                     break;

   101                 }

   102             }

   103 

   104             if (offset == 0) {

   105                 return null;

   106             }

   107 

   108             char[] ret = new char[offset];

   109             System.arraycopy(buf, 0, ret, 0, offset);

   110             Arrays.fill(buf, ' ');

   111 

   112             return ret;

   113         } finally {

   114             if (consoleEntered != null) {

   115                 Arrays.fill(consoleEntered, ' ');

   116             }

   117             if (consoleBytes != null) {

   118                 Arrays.fill(consoleBytes, (byte)0);

   119             }

   120         }

   121     }

   122 

   123     /**

   124      * Change a password read from Console.readPassword() into

   125      * its original bytes.

   126      *

   127      * @param pass a char[]

   128      * @return its byte[] format, similar to new String(pass).getBytes()

   129      */

   130     private static byte[] convertToBytes(char[] pass) {

   131         if (enc == null) {

   132             synchronized (Password.class) {

   133                 enc = sun.misc.SharedSecrets.getJavaIOAccess()

   134                         .charset()

   135                         .newEncoder()

   136                         .onMalformedInput(CodingErrorAction.REPLACE)

   137                         .onUnmappableCharacter(CodingErrorAction.REPLACE);

   138             }

   139         }

   140         byte[] ba = new byte[(int)(enc.maxBytesPerChar() * pass.length)];

   141         ByteBuffer bb = ByteBuffer.wrap(ba);

   142         synchronized (enc) {

   143             enc.reset().encode(CharBuffer.wrap(pass), bb, true);

   144         }

   145         if (bb.position() < ba.length) {

   146             ba[bb.position()] = '\n';

   147         }

   148         return ba;

   149     }

   150     private static volatile CharsetEncoder enc;

   151 }