1 /*
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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
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7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle 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.
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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 import jdk.internal.access.SharedSecrets;
33 
34 /**
35  * A utility class for reading passwords
36  *
37  */
38 public class Password {
39     /** Reads user password from given input stream. */
readPassword(InputStream in)40     public static char[] readPassword(InputStream in) throws IOException {
41         return readPassword(in, false);
42     }
43 
44     /** Reads user password from given input stream.
45      * @param isEchoOn true if the password should be echoed on the screen
46      */
47     @SuppressWarnings("fallthrough")
readPassword(InputStream in, boolean isEchoOn)48     public static char[] readPassword(InputStream in, boolean isEchoOn)
49             throws IOException {
50 
51         char[] consoleEntered = null;
52         byte[] consoleBytes = null;
53 
54         try {
55             // Use the new java.io.Console class
56             Console con = null;
57             if (!isEchoOn && in == System.in && ((con = System.console()) != null)) {
58                 consoleEntered = con.readPassword();
59                 // readPassword returns "" if you just print ENTER,
60                 // to be compatible with old Password class, change to null
61                 if (consoleEntered != null && consoleEntered.length == 0) {
62                     return null;
63                 }
64                 consoleBytes = convertToBytes(consoleEntered);
65                 in = new ByteArrayInputStream(consoleBytes);
66             }
67 
68             // Rest of the lines still necessary for KeyStoreLoginModule
69             // and when there is no console.
70 
71             char[] lineBuffer;
72             char[] buf;
73             int i;
74 
75             buf = lineBuffer = new char[128];
76 
77             int room = buf.length;
78             int offset = 0;
79             int c;
80 
81             boolean done = false;
82             while (!done) {
83                 switch (c = in.read()) {
84                   case -1:
85                   case '\n':
86                       done = true;
87                       break;
88 
89                   case '\r':
90                     int c2 = in.read();
91                     if ((c2 != '\n') && (c2 != -1)) {
92                         if (!(in instanceof PushbackInputStream)) {
93                             in = new PushbackInputStream(in);
94                         }
95                         ((PushbackInputStream)in).unread(c2);
96                     } else {
97                         done = true;
98                         break;
99                     }
100                     /* fall through */
101                   default:
102                     if (--room < 0) {
103                         buf = new char[offset + 128];
104                         room = buf.length - offset - 1;
105                         System.arraycopy(lineBuffer, 0, buf, 0, offset);
106                         Arrays.fill(lineBuffer, ' ');
107                         lineBuffer = buf;
108                     }
109                     buf[offset++] = (char) c;
110                     break;
111                 }
112             }
113 
114             if (offset == 0) {
115                 return null;
116             }
117 
118             char[] ret = new char[offset];
119             System.arraycopy(buf, 0, ret, 0, offset);
120             Arrays.fill(buf, ' ');
121 
122             return ret;
123         } finally {
124             if (consoleEntered != null) {
125                 Arrays.fill(consoleEntered, ' ');
126             }
127             if (consoleBytes != null) {
128                 Arrays.fill(consoleBytes, (byte)0);
129             }
130         }
131     }
132 
133     /**
134      * Change a password read from Console.readPassword() into
135      * its original bytes.
136      *
137      * @param pass a char[]
138      * @return its byte[] format, similar to new String(pass).getBytes()
139      */
convertToBytes(char[] pass)140     private static byte[] convertToBytes(char[] pass) {
141         if (enc == null) {
142             synchronized (Password.class) {
143                 enc = SharedSecrets.getJavaIOAccess()
144                         .charset()
145                         .newEncoder()
146                         .onMalformedInput(CodingErrorAction.REPLACE)
147                         .onUnmappableCharacter(CodingErrorAction.REPLACE);
148             }
149         }
150         byte[] ba = new byte[(int)(enc.maxBytesPerChar() * pass.length)];
151         ByteBuffer bb = ByteBuffer.wrap(ba);
152         synchronized (enc) {
153             enc.reset().encode(CharBuffer.wrap(pass), bb, true);
154         }
155         if (bb.position() < ba.length) {
156             ba[bb.position()] = '\n';
157         }
158         return ba;
159     }
160     private static volatile CharsetEncoder enc;
161 }
162