001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied. See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 *
019 */
020 package org.apache.directory.server.kerberos.shared.keytab;
021
022
023 import java.io.File;
024 import java.io.FileInputStream;
025 import java.io.FileOutputStream;
026 import java.io.IOException;
027 import java.io.InputStream;
028 import java.nio.channels.FileChannel;
029 import java.util.ArrayList;
030 import java.util.Collections;
031 import java.util.List;
032
033 import org.apache.directory.server.i18n.I18n;
034 import org.apache.mina.core.buffer.IoBuffer;
035
036
037 /**
038 * Keytab file.
039 *
040 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
041 * @version $Rev$, $Date$
042 */
043 public class Keytab
044 {
045 /**
046 * Byte array constant for keytab file format 5.1.
047 */
048 public static final byte[] VERSION_51 = new byte[]
049 { ( byte ) 0x05, ( byte ) 0x01 };
050
051 /**
052 * Byte array constant for keytab file format 5.2.
053 */
054 public static final byte[] VERSION_52 = new byte[]
055 { ( byte ) 0x05, ( byte ) 0x02 };
056
057 private byte[] keytabVersion = VERSION_52;
058 private List<KeytabEntry> entries = new ArrayList<KeytabEntry>();
059
060
061 /**
062 * Read a keytab file.
063 *
064 * @param file
065 * @return The keytab.
066 * @throws IOException
067 */
068 public static Keytab read( File file ) throws IOException
069 {
070 IoBuffer buffer = IoBuffer.wrap( getBytesFromFile( file ) );
071 return readKeytab( buffer );
072 }
073
074
075 /**
076 * Returns a new instance of a keytab with the version
077 * defaulted to 5.2.
078 *
079 * @return The keytab.
080 */
081 public static Keytab getInstance()
082 {
083 return new Keytab();
084 }
085
086
087 /**
088 * Write the keytab to a {@link File}.
089 *
090 * @param file
091 * @throws IOException
092 */
093 public void write( File file ) throws IOException
094 {
095 KeytabEncoder writer = new KeytabEncoder();
096 IoBuffer buffer = writer.write( keytabVersion, entries );
097 writeFile( buffer, file );
098 }
099
100
101 /**
102 * @param entries The entries to set.
103 */
104 public void setEntries( List<KeytabEntry> entries )
105 {
106 this.entries = entries;
107 }
108
109
110 /**
111 * @param keytabVersion The keytabVersion to set.
112 */
113 public void setKeytabVersion( byte[] keytabVersion )
114 {
115 this.keytabVersion = keytabVersion;
116 }
117
118
119 /**
120 * @return The entries.
121 */
122 public List<KeytabEntry> getEntries()
123 {
124 return Collections.unmodifiableList( entries );
125 }
126
127
128 /**
129 * @return The keytabVersion.
130 */
131 public byte[] getKeytabVersion()
132 {
133 return keytabVersion;
134 }
135
136
137 /**
138 * Read bytes into a keytab.
139 *
140 * @param bytes
141 * @return The keytab.
142 */
143 static Keytab read( byte[] bytes )
144 {
145 IoBuffer buffer = IoBuffer.wrap( bytes );
146 return readKeytab( buffer );
147 }
148
149
150 /**
151 * Write the keytab to a {@link ByteBuffer}.
152 * @return The buffer.
153 */
154 IoBuffer write()
155 {
156 KeytabEncoder writer = new KeytabEncoder();
157 return writer.write( keytabVersion, entries );
158 }
159
160
161 /**
162 * Read the contents of the buffer into a keytab.
163 *
164 * @param buffer
165 * @return The keytab.
166 */
167 private static Keytab readKeytab( IoBuffer buffer )
168 {
169 KeytabDecoder reader = new KeytabDecoder();
170 byte[] keytabVersion = reader.getKeytabVersion( buffer );
171 List<KeytabEntry> entries = reader.getKeytabEntries( buffer );
172
173 Keytab keytab = new Keytab();
174
175 keytab.setKeytabVersion( keytabVersion );
176 keytab.setEntries( entries );
177
178 return keytab;
179 }
180
181
182 /**
183 * Returns the contents of the {@link File} in a byte array.
184 *
185 * @param file
186 * @return The byte array of the file contents.
187 * @throws IOException
188 */
189 protected static byte[] getBytesFromFile( File file ) throws IOException
190 {
191 InputStream is = new FileInputStream( file );
192
193 long length = file.length();
194
195 // Check to ensure that file is not larger than Integer.MAX_VALUE.
196 if ( length > Integer.MAX_VALUE )
197 {
198 throw new IOException( I18n.err( I18n.ERR_618, file.getName() ) );
199 }
200
201 // Create the byte array to hold the data.
202 byte[] bytes = new byte[( int ) length];
203
204 // Read in the bytes
205 int offset = 0;
206 int numRead = 0;
207 while ( offset < bytes.length && ( numRead = is.read( bytes, offset, bytes.length - offset ) ) >= 0 )
208 {
209 offset += numRead;
210 }
211
212 // Ensure all the bytes have been read in.
213 if ( offset < bytes.length )
214 {
215 throw new IOException( I18n.err( I18n.ERR_619, file.getName() ) );
216 }
217
218 // Close the input stream and return bytes.
219 is.close();
220 return bytes;
221 }
222
223
224 /**
225 * Write the contents of the {@link ByteBuffer} to a {@link File}.
226 *
227 * @param buffer
228 * @param file
229 * @throws IOException
230 */
231 protected void writeFile( IoBuffer buffer, File file ) throws IOException
232 {
233 // Set append false to replace existing.
234 FileChannel wChannel = new FileOutputStream( file, false ).getChannel();
235
236 // Write the bytes between the position and limit.
237 wChannel.write( buffer.buf() );
238
239 wChannel.close();
240 }
241 }