1 /*
   2  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. 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.  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.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package java.util.jar;
  27 
  28 import java.util.zip.*;
  29 import java.io.*;
  30 import sun.security.util.ManifestEntryVerifier;
  31 import sun.misc.JarIndex;
  32 
  33 /**
  34  * The <code>JarInputStream</code> class is used to read the contents of
  35  * a JAR file from any input stream. It extends the class
  36  * <code>java.util.zip.ZipInputStream</code> with support for reading
  37  * an optional <code>Manifest</code> entry. The <code>Manifest</code>
  38  * can be used to store meta-information about the JAR file and its entries.
  39  *
  40  * @author  David Connelly
  41  * @see     Manifest
  42  * @see     java.util.zip.ZipInputStream
  43  * @since   1.2
  44  */
  45 public
  46 class JarInputStream extends ZipInputStream {
  47     private Manifest man;
  48     private JarEntry first;
  49     private JarVerifier jv;
  50     private ManifestEntryVerifier mev;
  51     private final boolean doVerify;
  52     private boolean tryManifest;
  53 
  54     /**
  55      * Creates a new <code>JarInputStream</code> and reads the optional
  56      * manifest. If a manifest is present, also attempts to verify
  57      * the signatures if the JarInputStream is signed.
  58      * @param in the actual input stream
  59      * @exception IOException if an I/O error has occurred
  60      */
  61     public JarInputStream(InputStream in) throws IOException {
  62         this(in, true);
  63     }
  64 
  65     /**
  66      * Creates a new <code>JarInputStream</code> and reads the optional
  67      * manifest. If a manifest is present and verify is true, also attempts
  68      * to verify the signatures if the JarInputStream is signed.
  69      *
  70      * @param in the actual input stream
  71      * @param verify whether or not to verify the JarInputStream if
  72      * it is signed.
  73      * @exception IOException if an I/O error has occurred
  74      */
  75     public JarInputStream(InputStream in, boolean verify) throws IOException {
  76         super(in);
  77         this.doVerify = verify;
  78 
  79         // This implementation assumes the META-INF/MANIFEST.MF entry
  80         // should be either the first or the second entry (when preceded
  81         // by the dir META-INF/). It skips the META-INF/ and then
  82         // "consumes" the MANIFEST.MF to initialize the Manifest object.
  83         JarEntry e = (JarEntry)super.getNextEntry();
  84         if (e != null && e.getName().equalsIgnoreCase("META-INF/"))
  85             e = (JarEntry)super.getNextEntry();
  86         first = checkManifest(e);
  87     }
  88 
  89     private JarEntry checkManifest(JarEntry e)
  90         throws IOException
  91     {
  92         if (e != null && JarFile.MANIFEST_NAME.equalsIgnoreCase(e.getName())) {
  93             man = new Manifest();
  94             byte bytes[] = getBytes(new BufferedInputStream(this));
  95             man.read(new ByteArrayInputStream(bytes));
  96             closeEntry();
  97             if (doVerify) {
  98                 jv = new JarVerifier(bytes);
  99                 mev = new ManifestEntryVerifier(man);
 100             }
 101             return (JarEntry)super.getNextEntry();
 102         }
 103         return e;
 104     }
 105 
 106     private byte[] getBytes(InputStream is)
 107         throws IOException
 108     {
 109         byte[] buffer = new byte[8192];
 110         ByteArrayOutputStream baos = new ByteArrayOutputStream(2048);
 111         int n;
 112         while ((n = is.read(buffer, 0, buffer.length)) != -1) {
 113             baos.write(buffer, 0, n);
 114         }
 115         return baos.toByteArray();
 116     }
 117 
 118     /**
 119      * Returns the <code>Manifest</code> for this JAR file, or
 120      * <code>null</code> if none.
 121      *
 122      * @return the <code>Manifest</code> for this JAR file, or
 123      *         <code>null</code> if none.
 124      */
 125     public Manifest getManifest() {
 126         return man;
 127     }
 128 
 129     /**
 130      * Reads the next ZIP file entry and positions the stream at the
 131      * beginning of the entry data. If verification has been enabled,
 132      * any invalid signature detected while positioning the stream for
 133      * the next entry will result in an exception.
 134      * @exception ZipException if a ZIP file error has occurred
 135      * @exception IOException if an I/O error has occurred
 136      * @exception SecurityException if any of the jar file entries
 137      *         are incorrectly signed.
 138      */
 139     public ZipEntry getNextEntry() throws IOException {
 140         JarEntry e;
 141         if (first == null) {
 142             e = (JarEntry)super.getNextEntry();
 143             if (tryManifest) {
 144                 e = checkManifest(e);
 145                 tryManifest = false;
 146             }
 147         } else {
 148             e = first;
 149             if (first.getName().equalsIgnoreCase(JarIndex.INDEX_NAME))
 150                 tryManifest = true;
 151             first = null;
 152         }
 153         if (jv != null && e != null) {
 154             // At this point, we might have parsed all the meta-inf
 155             // entries and have nothing to verify. If we have
 156             // nothing to verify, get rid of the JarVerifier object.
 157             if (jv.nothingToVerify() == true) {
 158                 jv = null;
 159                 mev = null;
 160             } else {
 161                 jv.beginEntry(e, mev);
 162             }
 163         }
 164         return e;
 165     }
 166 
 167     /**
 168      * Reads the next JAR file entry and positions the stream at the
 169      * beginning of the entry data. If verification has been enabled,
 170      * any invalid signature detected while positioning the stream for
 171      * the next entry will result in an exception.
 172      * @return the next JAR file entry, or null if there are no more entries
 173      * @exception ZipException if a ZIP file error has occurred
 174      * @exception IOException if an I/O error has occurred
 175      * @exception SecurityException if any of the jar file entries
 176      *         are incorrectly signed.
 177      */
 178     public JarEntry getNextJarEntry() throws IOException {
 179         return (JarEntry)getNextEntry();
 180     }
 181 
 182     /**
 183      * Reads from the current JAR file entry into an array of bytes.
 184      * If <code>len</code> is not zero, the method
 185      * blocks until some input is available; otherwise, no
 186      * bytes are read and <code>0</code> is returned.
 187      * If verification has been enabled, any invalid signature
 188      * on the current entry will be reported at some point before the
 189      * end of the entry is reached.
 190      * @param b the buffer into which the data is read
 191      * @param off the start offset in the destination array <code>b</code>
 192      * @param len the maximum number of bytes to read
 193      * @return the actual number of bytes read, or -1 if the end of the
 194      *         entry is reached
 195      * @exception  NullPointerException If <code>b</code> is <code>null</code>.
 196      * @exception  IndexOutOfBoundsException If <code>off</code> is negative,
 197      * <code>len</code> is negative, or <code>len</code> is greater than
 198      * <code>b.length - off</code>
 199      * @exception ZipException if a ZIP file error has occurred
 200      * @exception IOException if an I/O error has occurred
 201      * @exception SecurityException if any of the jar file entries
 202      *         are incorrectly signed.
 203      */
 204     public int read(byte[] b, int off, int len) throws IOException {
 205         int n;
 206         if (first == null) {
 207             n = super.read(b, off, len);
 208         } else {
 209             n = -1;
 210         }
 211         if (jv != null) {
 212             jv.update(n, b, off, len, mev);
 213         }
 214         return n;
 215     }
 216 
 217     /**
 218      * Creates a new <code>JarEntry</code> (<code>ZipEntry</code>) for the
 219      * specified JAR file entry name. The manifest attributes of
 220      * the specified JAR file entry name will be copied to the new
 221      * <CODE>JarEntry</CODE>.
 222      *
 223      * @param name the name of the JAR/ZIP file entry
 224      * @return the <code>JarEntry</code> object just created
 225      */
 226     protected ZipEntry createZipEntry(String name) {
 227         JarEntry e = new JarEntry(name);
 228         if (man != null) {
 229             e.attr = man.getAttributes(name);
 230         }
 231         return e;
 232     }
 233 }