1 /*
   2  * Copyright (c) 1995, 2015, 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.zip;
  27 
  28 import java.io.Closeable;
  29 import java.io.InputStream;
  30 import java.io.IOException;
  31 import java.io.EOFException;
  32 import java.io.File;
  33 import java.io.RandomAccessFile;
  34 import java.nio.charset.Charset;
  35 import java.nio.charset.StandardCharsets;
  36 import java.nio.file.attribute.BasicFileAttributes;
  37 import java.nio.file.Path;
  38 import java.nio.file.Files;
  39 
  40 import java.util.ArrayDeque;
  41 import java.util.ArrayList;
  42 import java.util.Arrays;
  43 import java.util.Deque;
  44 import java.util.Enumeration;
  45 import java.util.HashMap;
  46 import java.util.Iterator;
  47 import java.util.Map;
  48 import java.util.Objects;
  49 import java.util.NoSuchElementException;
  50 import java.util.Spliterator;
  51 import java.util.Spliterators;
  52 import java.util.WeakHashMap;
  53 import java.util.stream.Stream;
  54 import java.util.stream.StreamSupport;
  55 import jdk.internal.misc.JavaUtilZipFileAccess;
  56 import jdk.internal.misc.SharedSecrets;
  57 
  58 import static java.util.zip.ZipConstants.*;
  59 import static java.util.zip.ZipConstants64.*;
  60 import static java.util.zip.ZipUtils.*;
  61 
  62 /**
  63  * This class is used to read entries from a zip file.
  64  *
  65  * <p> Unless otherwise noted, passing a {@code null} argument to a constructor
  66  * or method in this class will cause a {@link NullPointerException} to be
  67  * thrown.
  68  *
  69  * @author      David Connelly
  70  */
  71 public
  72 class ZipFile implements ZipConstants, Closeable {
  73 
  74     private final String name;     // zip file name
  75     private volatile boolean closeRequested = false;
  76     private Source zsrc;
  77     private ZipCoder zc;
  78 
  79     private static final int STORED = ZipEntry.STORED;
  80     private static final int DEFLATED = ZipEntry.DEFLATED;
  81 
  82     /**
  83      * Mode flag to open a zip file for reading.
  84      */
  85     public static final int OPEN_READ = 0x1;
  86 
  87     /**
  88      * Mode flag to open a zip file and mark it for deletion.  The file will be
  89      * deleted some time between the moment that it is opened and the moment
  90      * that it is closed, but its contents will remain accessible via the
  91      * {@code ZipFile} object until either the close method is invoked or the
  92      * virtual machine exits.
  93      */
  94     public static final int OPEN_DELETE = 0x4;
  95 
  96     /**
  97      * Opens a zip file for reading.
  98      *
  99      * <p>First, if there is a security manager, its {@code checkRead}
 100      * method is called with the {@code name} argument as its argument
 101      * to ensure the read is allowed.
 102      *
 103      * <p>The UTF-8 {@link java.nio.charset.Charset charset} is used to
 104      * decode the entry names and comments.
 105      *
 106      * @param name the name of the zip file
 107      * @throws ZipException if a ZIP format error has occurred
 108      * @throws IOException if an I/O error has occurred
 109      * @throws SecurityException if a security manager exists and its
 110      *         {@code checkRead} method doesn't allow read access to the file.
 111      *
 112      * @see SecurityManager#checkRead(java.lang.String)
 113      */
 114     public ZipFile(String name) throws IOException {
 115         this(new File(name), OPEN_READ);
 116     }
 117 
 118     /**
 119      * Opens a new {@code ZipFile} to read from the specified
 120      * {@code File} object in the specified mode.  The mode argument
 121      * must be either {@code OPEN_READ} or {@code OPEN_READ | OPEN_DELETE}.
 122      *
 123      * <p>First, if there is a security manager, its {@code checkRead}
 124      * method is called with the {@code name} argument as its argument to
 125      * ensure the read is allowed.
 126      *
 127      * <p>The UTF-8 {@link java.nio.charset.Charset charset} is used to
 128      * decode the entry names and comments
 129      *
 130      * @param file the ZIP file to be opened for reading
 131      * @param mode the mode in which the file is to be opened
 132      * @throws ZipException if a ZIP format error has occurred
 133      * @throws IOException if an I/O error has occurred
 134      * @throws SecurityException if a security manager exists and
 135      *         its {@code checkRead} method
 136      *         doesn't allow read access to the file,
 137      *         or its {@code checkDelete} method doesn't allow deleting
 138      *         the file when the {@code OPEN_DELETE} flag is set.
 139      * @throws IllegalArgumentException if the {@code mode} argument is invalid
 140      * @see SecurityManager#checkRead(java.lang.String)
 141      * @since 1.3
 142      */
 143     public ZipFile(File file, int mode) throws IOException {
 144         this(file, mode, StandardCharsets.UTF_8);
 145     }
 146 
 147     /**
 148      * Opens a ZIP file for reading given the specified File object.
 149      *
 150      * <p>The UTF-8 {@link java.nio.charset.Charset charset} is used to
 151      * decode the entry names and comments.
 152      *
 153      * @param file the ZIP file to be opened for reading
 154      * @throws ZipException if a ZIP format error has occurred
 155      * @throws IOException if an I/O error has occurred
 156      */
 157     public ZipFile(File file) throws ZipException, IOException {
 158         this(file, OPEN_READ);
 159     }
 160 
 161     /**
 162      * Opens a new {@code ZipFile} to read from the specified
 163      * {@code File} object in the specified mode.  The mode argument
 164      * must be either {@code OPEN_READ} or {@code OPEN_READ | OPEN_DELETE}.
 165      *
 166      * <p>First, if there is a security manager, its {@code checkRead}
 167      * method is called with the {@code name} argument as its argument to
 168      * ensure the read is allowed.
 169      *
 170      * @param file the ZIP file to be opened for reading
 171      * @param mode the mode in which the file is to be opened
 172      * @param charset
 173      *        the {@linkplain java.nio.charset.Charset charset} to
 174      *        be used to decode the ZIP entry name and comment that are not
 175      *        encoded by using UTF-8 encoding (indicated by entry's general
 176      *        purpose flag).
 177      *
 178      * @throws ZipException if a ZIP format error has occurred
 179      * @throws IOException if an I/O error has occurred
 180      *
 181      * @throws SecurityException
 182      *         if a security manager exists and its {@code checkRead}
 183      *         method doesn't allow read access to the file,or its
 184      *         {@code checkDelete} method doesn't allow deleting the
 185      *         file when the {@code OPEN_DELETE} flag is set
 186      *
 187      * @throws IllegalArgumentException if the {@code mode} argument is invalid
 188      *
 189      * @see SecurityManager#checkRead(java.lang.String)
 190      *
 191      * @since 1.7
 192      */
 193     public ZipFile(File file, int mode, Charset charset) throws IOException
 194     {
 195         if (((mode & OPEN_READ) == 0) ||
 196             ((mode & ~(OPEN_READ | OPEN_DELETE)) != 0)) {
 197             throw new IllegalArgumentException("Illegal mode: 0x"+
 198                                                Integer.toHexString(mode));
 199         }
 200         String name = file.getPath();
 201         SecurityManager sm = System.getSecurityManager();
 202         if (sm != null) {
 203             sm.checkRead(name);
 204             if ((mode & OPEN_DELETE) != 0) {
 205                 sm.checkDelete(name);
 206             }
 207         }
 208         Objects.requireNonNull(charset, "charset");
 209         this.zc = ZipCoder.get(charset);
 210         this.name = name;
 211         long t0 = System.nanoTime();
 212         this.zsrc = Source.get(file, (mode & OPEN_DELETE) != 0);
 213         sun.misc.PerfCounter.getZipFileOpenTime().addElapsedTimeFrom(t0);
 214         sun.misc.PerfCounter.getZipFileCount().increment();
 215     }
 216 
 217     /**
 218      * Opens a zip file for reading.
 219      *
 220      * <p>First, if there is a security manager, its {@code checkRead}
 221      * method is called with the {@code name} argument as its argument
 222      * to ensure the read is allowed.
 223      *
 224      * @param name the name of the zip file
 225      * @param charset
 226      *        the {@linkplain java.nio.charset.Charset charset} to
 227      *        be used to decode the ZIP entry name and comment that are not
 228      *        encoded by using UTF-8 encoding (indicated by entry's general
 229      *        purpose flag).
 230      *
 231      * @throws ZipException if a ZIP format error has occurred
 232      * @throws IOException if an I/O error has occurred
 233      * @throws SecurityException
 234      *         if a security manager exists and its {@code checkRead}
 235      *         method doesn't allow read access to the file
 236      *
 237      * @see SecurityManager#checkRead(java.lang.String)
 238      *
 239      * @since 1.7
 240      */
 241     public ZipFile(String name, Charset charset) throws IOException
 242     {
 243         this(new File(name), OPEN_READ, charset);
 244     }
 245 
 246     /**
 247      * Opens a ZIP file for reading given the specified File object.
 248      *
 249      * @param file the ZIP file to be opened for reading
 250      * @param charset
 251      *        The {@linkplain java.nio.charset.Charset charset} to be
 252      *        used to decode the ZIP entry name and comment (ignored if
 253      *        the <a href="package-summary.html#lang_encoding"> language
 254      *        encoding bit</a> of the ZIP entry's general purpose bit
 255      *        flag is set).
 256      *
 257      * @throws ZipException if a ZIP format error has occurred
 258      * @throws IOException if an I/O error has occurred
 259      *
 260      * @since 1.7
 261      */
 262     public ZipFile(File file, Charset charset) throws IOException
 263     {
 264         this(file, OPEN_READ, charset);
 265     }
 266 
 267     /**
 268      * Returns the zip file comment, or null if none.
 269      *
 270      * @return the comment string for the zip file, or null if none
 271      *
 272      * @throws IllegalStateException if the zip file has been closed
 273      *
 274      * Since 1.7
 275      */
 276     public String getComment() {
 277         synchronized (this) {
 278             ensureOpen();
 279             if (zsrc.comment == null) {
 280                 return null;
 281             }
 282             return zc.toString(zsrc.comment);
 283         }
 284     }
 285 
 286     /**
 287      * Returns the zip file entry for the specified name, or null
 288      * if not found.
 289      *
 290      * @param name the name of the entry
 291      * @return the zip file entry, or null if not found
 292      * @throws IllegalStateException if the zip file has been closed
 293      */
 294     public ZipEntry getEntry(String name) {
 295 
 296         Objects.requireNonNull(name, "name");
 297         synchronized (this) {
 298             ensureOpen();
 299             int pos = zsrc.getEntryPos(zc.getBytes(name), true);
 300             if (pos != -1) {
 301                 return getZipEntry(name, pos);
 302             }
 303         }
 304         return null;
 305     }
 306 
 307     // The outstanding inputstreams that need to be closed,
 308     // mapped to the inflater objects they use.
 309     private final Map<InputStream, Inflater> streams = new WeakHashMap<>();
 310 
 311     /**
 312      * Returns an input stream for reading the contents of the specified
 313      * zip file entry.
 314      * <p>
 315      * Closing this ZIP file will, in turn, close all input streams that
 316      * have been returned by invocations of this method.
 317      *
 318      * @param entry the zip file entry
 319      * @return the input stream for reading the contents of the specified
 320      * zip file entry.
 321      * @throws ZipException if a ZIP format error has occurred
 322      * @throws IOException if an I/O error has occurred
 323      * @throws IllegalStateException if the zip file has been closed
 324      */
 325     public InputStream getInputStream(ZipEntry entry) throws IOException {
 326         Objects.requireNonNull(entry, "entry");
 327         int pos = -1;
 328         ZipFileInputStream in = null;
 329         synchronized (this) {
 330             ensureOpen();
 331             if (!zc.isUTF8() && (entry.flag & EFS) != 0) {
 332                 pos = zsrc.getEntryPos(zc.getBytesUTF8(entry.name), false);
 333             } else {
 334                 pos = zsrc.getEntryPos(zc.getBytes(entry.name), false);
 335             }
 336             if (pos == -1) {
 337                 return null;
 338             }
 339             in = new ZipFileInputStream(zsrc.cen, pos);
 340             switch (CENHOW(zsrc.cen, pos)) {
 341             case STORED:
 342                 synchronized (streams) {
 343                     streams.put(in, null);
 344                 }
 345                 return in;
 346             case DEFLATED:
 347                 // Inflater likes a bit of slack
 348                 // MORE: Compute good size for inflater stream:
 349                 long size = CENLEN(zsrc.cen, pos) + 2;
 350                 if (size > 65536) {
 351                     size = 8192;
 352                 }
 353                 if (size <= 0) {
 354                     size = 4096;
 355                 }
 356                 Inflater inf = getInflater();
 357                 InputStream is = new ZipFileInflaterInputStream(in, inf, (int)size);
 358                 synchronized (streams) {
 359                     streams.put(is, inf);
 360                 }
 361                 return is;
 362             default:
 363                 throw new ZipException("invalid compression method");
 364             }
 365         }
 366     }
 367 
 368     private class ZipFileInflaterInputStream extends InflaterInputStream {
 369         private volatile boolean closeRequested = false;
 370         private boolean eof = false;
 371         private final ZipFileInputStream zfin;
 372 
 373         ZipFileInflaterInputStream(ZipFileInputStream zfin, Inflater inf,
 374                 int size) {
 375             super(zfin, inf, size);
 376             this.zfin = zfin;
 377         }
 378 
 379         public void close() throws IOException {
 380             if (closeRequested)
 381                 return;
 382             closeRequested = true;
 383 
 384             super.close();
 385             Inflater inf;
 386             synchronized (streams) {
 387                 inf = streams.remove(this);
 388             }
 389             if (inf != null) {
 390                 releaseInflater(inf);
 391             }
 392         }
 393 
 394         // Override fill() method to provide an extra "dummy" byte
 395         // at the end of the input stream. This is required when
 396         // using the "nowrap" Inflater option.
 397         protected void fill() throws IOException {
 398             if (eof) {
 399                 throw new EOFException("Unexpected end of ZLIB input stream");
 400             }
 401             len = in.read(buf, 0, buf.length);
 402             if (len == -1) {
 403                 buf[0] = 0;
 404                 len = 1;
 405                 eof = true;
 406             }
 407             inf.setInput(buf, 0, len);
 408         }
 409 
 410         public int available() throws IOException {
 411             if (closeRequested)
 412                 return 0;
 413             long avail = zfin.size() - inf.getBytesWritten();
 414             return (avail > (long) Integer.MAX_VALUE ?
 415                     Integer.MAX_VALUE : (int) avail);
 416         }
 417 
 418         protected void finalize() throws Throwable {
 419             close();
 420         }
 421     }
 422 
 423     /*
 424      * Gets an inflater from the list of available inflaters or allocates
 425      * a new one.
 426      */
 427     private Inflater getInflater() {
 428         Inflater inf;
 429         synchronized (inflaterCache) {
 430             while ((inf = inflaterCache.poll()) != null) {
 431                 if (!inf.ended()) {
 432                     return inf;
 433                 }
 434             }
 435         }
 436         return new Inflater(true);
 437     }
 438 
 439     /*
 440      * Releases the specified inflater to the list of available inflaters.
 441      */
 442     private void releaseInflater(Inflater inf) {
 443         if (!inf.ended()) {
 444             inf.reset();
 445             synchronized (inflaterCache) {
 446                 inflaterCache.add(inf);
 447             }
 448         }
 449     }
 450 
 451     // List of available Inflater objects for decompression
 452     private final Deque<Inflater> inflaterCache = new ArrayDeque<>();
 453 
 454     /**
 455      * Returns the path name of the ZIP file.
 456      * @return the path name of the ZIP file
 457      */
 458     public String getName() {
 459         return name;
 460     }
 461 
 462     private class ZipEntryIterator implements Enumeration<ZipEntry>, Iterator<ZipEntry> {
 463         private int i = 0;
 464 
 465         public ZipEntryIterator() {
 466             ensureOpen();
 467         }
 468 
 469         public boolean hasMoreElements() {
 470             return hasNext();
 471         }
 472 
 473         public boolean hasNext() {
 474             synchronized (ZipFile.this) {
 475                 ensureOpen();
 476                 return i < zsrc.total;
 477             }
 478         }
 479 
 480         public ZipEntry nextElement() {
 481             return next();
 482         }
 483 
 484         public ZipEntry next() {
 485             synchronized (ZipFile.this) {
 486                 ensureOpen();
 487                 if (i >= zsrc.total) {
 488                     throw new NoSuchElementException();
 489                 }
 490                 // each "entry" has 3 ints in table entries
 491                 return getZipEntry(null, zsrc.getEntryPos(i++ * 3));
 492             }
 493         }
 494 
 495         public Iterator<ZipEntry> asIterator() {
 496             return this;
 497         }
 498     }
 499 
 500     /**
 501      * Returns an enumeration of the ZIP file entries.
 502      * @return an enumeration of the ZIP file entries
 503      * @throws IllegalStateException if the zip file has been closed
 504      */
 505     public Enumeration<? extends ZipEntry> entries() {
 506         return new ZipEntryIterator();
 507     }
 508 
 509     /**
 510      * Returns an ordered {@code Stream} over the ZIP file entries.
 511      * Entries appear in the {@code Stream} in the order they appear in
 512      * the central directory of the ZIP file.
 513      *
 514      * @return an ordered {@code Stream} of entries in this ZIP file
 515      * @throws IllegalStateException if the zip file has been closed
 516      * @since 1.8
 517      */
 518     public Stream<? extends ZipEntry> stream() {
 519         return StreamSupport.stream(Spliterators.spliterator(
 520                 new ZipEntryIterator(), size(),
 521                 Spliterator.ORDERED | Spliterator.DISTINCT |
 522                         Spliterator.IMMUTABLE | Spliterator.NONNULL), false);
 523     }
 524 
 525     /* Checks ensureOpen() before invoke this method */
 526     private ZipEntry getZipEntry(String name, int pos) {
 527         byte[] cen = zsrc.cen;
 528         ZipEntry e = new ZipEntry();
 529         int nlen = CENNAM(cen, pos);
 530         int elen = CENEXT(cen, pos);
 531         int clen = CENCOM(cen, pos);
 532         e.flag = CENFLG(cen, pos);  // get the flag first
 533         if (name != null) {
 534             e.name = name;
 535         } else {
 536             if (!zc.isUTF8() && (e.flag & EFS) != 0) {
 537                 e.name = zc.toStringUTF8(cen, pos + CENHDR, nlen);
 538             } else {
 539                 e.name = zc.toString(cen, pos + CENHDR, nlen);
 540             }
 541         }
 542         e.xdostime = CENTIM(cen, pos);
 543         e.crc = CENCRC(cen, pos);
 544         e.size = CENLEN(cen, pos);
 545         e.csize = CENSIZ(cen, pos);
 546         e.method = CENHOW(cen, pos);
 547         if (elen != 0) {
 548             e.setExtra0(Arrays.copyOfRange(cen, pos + CENHDR + nlen,
 549                                            pos + CENHDR + nlen + elen), true);
 550         }
 551         if (clen != 0) {
 552             if (!zc.isUTF8() && (e.flag & EFS) != 0) {
 553                 e.comment = zc.toStringUTF8(cen, pos + CENHDR + nlen + elen, clen);
 554             } else {
 555                 e.comment = zc.toString(cen, pos + CENHDR + nlen + elen, clen);
 556             }
 557         }
 558         return e;
 559     }
 560 
 561     /**
 562      * Returns the number of entries in the ZIP file.
 563      *
 564      * @return the number of entries in the ZIP file
 565      * @throws IllegalStateException if the zip file has been closed
 566      */
 567     public int size() {
 568         synchronized (this) {
 569             ensureOpen();
 570             return zsrc.total;
 571         }
 572     }
 573 
 574     /**
 575      * Closes the ZIP file.
 576      * <p> Closing this ZIP file will close all of the input streams
 577      * previously returned by invocations of the {@link #getInputStream
 578      * getInputStream} method.
 579      *
 580      * @throws IOException if an I/O error has occurred
 581      */
 582     public void close() throws IOException {
 583         if (closeRequested) {
 584             return;
 585         }
 586         closeRequested = true;
 587 
 588         synchronized (this) {
 589             // Close streams, release their inflaters
 590             synchronized (streams) {
 591                 if (!streams.isEmpty()) {
 592                     Map<InputStream, Inflater> copy = new HashMap<>(streams);
 593                     streams.clear();
 594                     for (Map.Entry<InputStream, Inflater> e : copy.entrySet()) {
 595                         e.getKey().close();
 596                         Inflater inf = e.getValue();
 597                         if (inf != null) {
 598                             inf.end();
 599                         }
 600                     }
 601                 }
 602             }
 603             // Release cached inflaters
 604             synchronized (inflaterCache) {
 605                 Inflater inf;
 606                 while ((inf = inflaterCache.poll()) != null) {
 607                     inf.end();
 608                 }
 609             }
 610             // Release zip src
 611             if (zsrc != null) {
 612                 Source.close(zsrc);
 613                 zsrc = null;
 614             }
 615         }
 616     }
 617 
 618     /**
 619      * Ensures that the system resources held by this ZipFile object are
 620      * released when there are no more references to it.
 621      *
 622      * <p>
 623      * Since the time when GC would invoke this method is undetermined,
 624      * it is strongly recommended that applications invoke the {@code close}
 625      * method as soon they have finished accessing this {@code ZipFile}.
 626      * This will prevent holding up system resources for an undetermined
 627      * length of time.
 628      *
 629      * @throws IOException if an I/O error has occurred
 630      * @see    java.util.zip.ZipFile#close()
 631      */
 632     protected void finalize() throws IOException {
 633         close();
 634     }
 635 
 636     private void ensureOpen() {
 637         if (closeRequested) {
 638             throw new IllegalStateException("zip file closed");
 639         }
 640         if (zsrc == null) {
 641             throw new IllegalStateException("The object is not initialized.");
 642         }
 643     }
 644 
 645     private void ensureOpenOrZipException() throws IOException {
 646         if (closeRequested) {
 647             throw new ZipException("ZipFile closed");
 648         }
 649     }
 650 
 651     /*
 652      * Inner class implementing the input stream used to read a
 653      * (possibly compressed) zip file entry.
 654      */
 655    private class ZipFileInputStream extends InputStream {
 656         private volatile boolean closeRequested = false;
 657         private   long pos;     // current position within entry data
 658         protected long rem;     // number of remaining bytes within entry
 659         protected long size;    // uncompressed size of this entry
 660 
 661         ZipFileInputStream(byte[] cen, int cenpos) throws IOException {
 662             rem = CENSIZ(cen, cenpos);
 663             size = CENLEN(cen, cenpos);
 664             pos = CENOFF(cen, cenpos);
 665             // zip64
 666             if (rem == ZIP64_MAGICVAL || size == ZIP64_MAGICVAL ||
 667                 pos == ZIP64_MAGICVAL) {
 668                 checkZIP64(cen, cenpos);
 669             }
 670             // negative for lazy initialization, see getDataOffset();
 671             pos = - (pos + ZipFile.this.zsrc.locpos);
 672         }
 673 
 674         private void checkZIP64(byte[] cen, int cenpos) throws IOException {
 675             int off = cenpos + CENHDR + CENNAM(cen, cenpos);
 676             int end = off + CENEXT(cen, cenpos);
 677             while (off + 4 < end) {
 678                 int tag = get16(cen, off);
 679                 int sz = get16(cen, off + 2);
 680                 off += 4;
 681                 if (off + sz > end)         // invalid data
 682                     break;
 683                 if (tag == EXTID_ZIP64) {
 684                     if (size == ZIP64_MAGICVAL) {
 685                         if (sz < 8 || (off + 8) > end)
 686                             break;
 687                         size = get64(cen, off);
 688                         sz -= 8;
 689                         off += 8;
 690                     }
 691                     if (rem == ZIP64_MAGICVAL) {
 692                         if (sz < 8 || (off + 8) > end)
 693                             break;
 694                         rem = get64(cen, off);
 695                         sz -= 8;
 696                         off += 8;
 697                     }
 698                     if (pos == ZIP64_MAGICVAL) {
 699                         if (sz < 8 || (off + 8) > end)
 700                             break;
 701                         pos = get64(cen, off);
 702                         sz -= 8;
 703                         off += 8;
 704                     }
 705                     break;
 706                 }
 707                 off += sz;
 708             }
 709         }
 710 
 711        /* The Zip file spec explicitly allows the LOC extra data size to
 712         * be different from the CEN extra data size. Since we cannot trust
 713         * the CEN extra data size, we need to read the LOC to determine
 714         * the entry data offset.
 715         */
 716         private long initDataOffset() throws IOException {
 717             if (pos <= 0) {
 718                 byte[] loc = new byte[LOCHDR];
 719                 pos = -pos;
 720                 int len = ZipFile.this.zsrc.readFullyAt(loc, 0, loc.length, pos);
 721                 if (len != LOCHDR) {
 722                     throw new ZipException("ZipFile error reading zip file");
 723                 }
 724                 if (LOCSIG(loc) != LOCSIG) {
 725                     throw new ZipException("ZipFile invalid LOC header (bad signature)");
 726                 }
 727                 pos += LOCHDR + LOCNAM(loc) + LOCEXT(loc);
 728             }
 729             return pos;
 730         }
 731 
 732         public int read(byte b[], int off, int len) throws IOException {
 733             synchronized (ZipFile.this) {
 734                 ensureOpenOrZipException();
 735                 initDataOffset();
 736                 if (rem == 0) {
 737                     return -1;
 738                 }
 739                 if (len > rem) {
 740                     len = (int) rem;
 741                 }
 742                 if (len <= 0) {
 743                     return 0;
 744                 }
 745                 len = ZipFile.this.zsrc.readAt(b, off, len, pos);
 746                 if (len > 0) {
 747                     pos += len;
 748                     rem -= len;
 749                 }
 750             }
 751             if (rem == 0) {
 752                 close();
 753             }
 754             return len;
 755         }
 756 
 757         public int read() throws IOException {
 758             byte[] b = new byte[1];
 759             if (read(b, 0, 1) == 1) {
 760                 return b[0] & 0xff;
 761             } else {
 762                 return -1;
 763             }
 764         }
 765 
 766         public long skip(long n) throws IOException {
 767             synchronized (ZipFile.this) {
 768                 ensureOpenOrZipException();
 769                 initDataOffset();
 770                 if (n > rem) {
 771                     n = rem;
 772                 }
 773                 pos += n;
 774                 rem -= n;
 775             }
 776             if (rem == 0) {
 777                 close();
 778             }
 779             return n;
 780         }
 781 
 782         public int available() {
 783             return rem > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int) rem;
 784         }
 785 
 786         public long size() {
 787             return size;
 788         }
 789 
 790         public void close() {
 791             if (closeRequested) {
 792                 return;
 793             }
 794             closeRequested = true;
 795             rem = 0;
 796             synchronized (streams) {
 797                 streams.remove(this);
 798             }
 799         }
 800 
 801         protected void finalize() {
 802             close();
 803         }
 804     }
 805 
 806     static {
 807         SharedSecrets.setJavaUtilZipFileAccess(
 808             new JavaUtilZipFileAccess() {
 809                 public boolean startsWithLocHeader(ZipFile zip) {
 810                     return zip.zsrc.startsWithLoc;
 811                 }
 812                 public String[] getMetaInfEntryNames(ZipFile zip) {
 813                     return zip.getMetaInfEntryNames();
 814                 }
 815              }
 816         );
 817     }
 818 
 819     /*
 820      * Returns an array of strings representing the names of all entries
 821      * that begin with "META-INF/" (case ignored). This method is used
 822      * in JarFile, via SharedSecrets, as an optimization when looking up
 823      * manifest and signature file entries. Returns null if no entries
 824      * were found.
 825      */
 826     private String[] getMetaInfEntryNames() {
 827         synchronized (this) {
 828             ensureOpen();
 829             if (zsrc.metanames.size() == 0) {
 830                 return null;
 831             }
 832             String[] names = new String[zsrc.metanames.size()];
 833             byte[] cen = zsrc.cen;
 834             for (int i = 0; i < names.length; i++) {
 835                 int pos = zsrc.metanames.get(i);
 836                 names[i] = new String(cen, pos + CENHDR,  CENNAM(cen, pos),
 837                                       StandardCharsets.UTF_8);
 838             }
 839             return names;
 840         }
 841     }
 842 
 843     private static class Source {
 844         private final Key key;               // the key in files
 845         private int refs = 1;
 846 
 847         private RandomAccessFile zfile;      // zfile of the underlying zip file
 848         private byte[] cen;                  // CEN & ENDHDR
 849         private long locpos;                 // position of first LOC header (usually 0)
 850         private byte[] comment;              // zip file comment
 851                                              // list of meta entries in META-INF dir
 852         private ArrayList<Integer> metanames = new ArrayList<>();
 853         private final boolean startsWithLoc; // true, if zip file starts with LOCSIG (usually true)
 854 
 855         // A Hashmap for all entries.
 856         //
 857         // A cen entry of Zip/JAR file. As we have one for every entry in every active Zip/JAR,
 858         // We might have a lot of these in a typical system. In order to save space we don't
 859         // keep the name in memory, but merely remember a 32 bit {@code hash} value of the
 860         // entry name and its offset {@code pos} in the central directory hdeader.
 861         //
 862         // private static class Entry {
 863         //     int hash;       // 32 bit hashcode on name
 864         //     int next;       // hash chain: index into entries
 865         //     int pos;        // Offset of central directory file header
 866         // }
 867         // private Entry[] entries;             // array of hashed cen entry
 868         //
 869         // To reduce the total size of entries further, we use a int[] here to store 3 "int"
 870         // {@code hash}, {@code next and {@code "pos for each entry. The entry can then be
 871         // referred by their index of their positions in the {@code entries}.
 872         //
 873         private int[] entries;                  // array of hashed cen entry
 874         private int addEntry(int index, int hash, int next, int pos) {
 875             entries[index++] = hash;
 876             entries[index++] = next;
 877             entries[index++] = pos;
 878             return index;
 879         }
 880         private int getEntryHash(int index) { return entries[index]; }
 881         private int getEntryNext(int index) { return entries[index + 1]; }
 882         private int getEntryPos(int index)  { return entries[index + 2]; }
 883         private static final int ZIP_ENDCHAIN  = -1;
 884         private int total;                   // total number of entries
 885         private int[] table;                 // Hash chain heads: indexes into entries
 886         private int tablelen;                // number of hash heads
 887 
 888         private static class Key {
 889             BasicFileAttributes attrs;
 890             File file;
 891 
 892             public Key(File file, BasicFileAttributes attrs) {
 893                 this.attrs = attrs;
 894                 this.file = file;
 895             }
 896 
 897             public int hashCode() {
 898                 long t = attrs.lastModifiedTime().toMillis();
 899                 return ((int)(t ^ (t >>> 32))) + file.hashCode();
 900             }
 901 
 902             public boolean equals(Object obj) {
 903                 if (obj instanceof Key) {
 904                     Key key = (Key)obj;
 905                     if (!attrs.lastModifiedTime().equals(key.attrs.lastModifiedTime())) {
 906                         return false;
 907                     }
 908                     Object fk = attrs.fileKey();
 909                     if (fk != null) {
 910                         return  fk.equals(key.attrs.fileKey());
 911                     } else {
 912                         return file.equals(key.file);
 913                     }
 914                 }
 915                 return false;
 916             }
 917         }
 918         private static final HashMap<Key, Source> files = new HashMap<>();
 919 
 920 
 921         public static Source get(File file, boolean toDelete) throws IOException {
 922             Key key = new Key(file,
 923                               Files.readAttributes(file.toPath(), BasicFileAttributes.class));
 924             Source src = null;
 925             synchronized (files) {
 926                 src = files.get(key);
 927                 if (src != null) {
 928                     src.refs++;
 929                     return src;
 930                 }
 931             }
 932             src = new Source(key, toDelete);
 933 
 934             synchronized (files) {
 935                 if (files.containsKey(key)) {    // someone else put in first
 936                     src.close();                 // close the newly created one
 937                     src = files.get(key);
 938                     src.refs++;
 939                     return src;
 940                 }
 941                 files.put(key, src);
 942                 return src;
 943             }
 944         }
 945 
 946         private static void close(Source src) throws IOException {
 947             synchronized (files) {
 948                 if (--src.refs == 0) {
 949                     files.remove(src.key);
 950                     src.close();
 951                 }
 952             }
 953         }
 954 
 955         private Source(Key key, boolean toDelete) throws IOException {
 956             this.key = key;
 957             this.zfile = new RandomAccessFile(key.file, "r");
 958             if (toDelete) {
 959                 key.file.delete();
 960             }
 961             try {
 962                 initCEN(-1);
 963                 byte[] buf = new byte[4];
 964                 readFullyAt(buf, 0, 4, 0);
 965                 this.startsWithLoc = (LOCSIG(buf) == LOCSIG);
 966             } catch (IOException x) {
 967                 try {
 968                     this.zfile.close();
 969                 } catch (IOException xx) {}
 970                 throw x;
 971             }
 972         }
 973 
 974         private void close() throws IOException {
 975             zfile.close();
 976             zfile = null;
 977             cen = null;
 978             entries = null;
 979             table = null;
 980             metanames = null;
 981         }
 982 
 983         private static final int BUF_SIZE = 8192;
 984         private final int readFullyAt(byte[] buf, int off, int len, long pos)
 985             throws IOException
 986         {
 987             synchronized(zfile) {
 988                 zfile.seek(pos);
 989                 int N = len;
 990                 while (N > 0) {
 991                     int n = Math.min(BUF_SIZE, N);
 992                     zfile.readFully(buf, off, n);
 993                     off += n;
 994                     N -= n;
 995                 }
 996                 return len;
 997             }
 998         }
 999 
1000         private final int readAt(byte[] buf, int off, int len, long pos)
1001             throws IOException
1002         {
1003             synchronized(zfile) {
1004                 zfile.seek(pos);
1005                 return zfile.read(buf, off, len);
1006             }
1007         }
1008 
1009         private static final int hashN(byte[] a, int off, int len) {
1010             int h = 1;
1011             while (len-- > 0) {
1012                 h = 31 * h + a[off++];
1013             }
1014             return h;
1015         }
1016 
1017         private static final int hash_append(int hash, byte b) {
1018             return hash * 31 + b;
1019         }
1020 
1021         private static class End {
1022             int  centot;     // 4 bytes
1023             long cenlen;     // 4 bytes
1024             long cenoff;     // 4 bytes
1025             long endpos;     // 4 bytes
1026         }
1027 
1028         /*
1029          * Searches for end of central directory (END) header. The contents of
1030          * the END header will be read and placed in endbuf. Returns the file
1031          * position of the END header, otherwise returns -1 if the END header
1032          * was not found or an error occurred.
1033          */
1034         private End findEND() throws IOException {
1035             long ziplen = zfile.length();
1036             if (ziplen <= 0)
1037                 zerror("zip file is empty");
1038             End end = new End();
1039             byte[] buf = new byte[READBLOCKSZ];
1040             long minHDR = (ziplen - END_MAXLEN) > 0 ? ziplen - END_MAXLEN : 0;
1041             long minPos = minHDR - (buf.length - ENDHDR);
1042             for (long pos = ziplen - buf.length; pos >= minPos; pos -= (buf.length - ENDHDR)) {
1043                 int off = 0;
1044                 if (pos < 0) {
1045                     // Pretend there are some NUL bytes before start of file
1046                     off = (int)-pos;
1047                     Arrays.fill(buf, 0, off, (byte)0);
1048                 }
1049                 int len = buf.length - off;
1050                 if (readFullyAt(buf, off, len, pos + off) != len ) {
1051                     zerror("zip END header not found");
1052                 }
1053                 // Now scan the block backwards for END header signature
1054                 for (int i = buf.length - ENDHDR; i >= 0; i--) {
1055                     if (buf[i+0] == (byte)'P'    &&
1056                         buf[i+1] == (byte)'K'    &&
1057                         buf[i+2] == (byte)'\005' &&
1058                         buf[i+3] == (byte)'\006') {
1059                         // Found ENDSIG header
1060                         byte[] endbuf = Arrays.copyOfRange(buf, i, i + ENDHDR);
1061                         end.centot = ENDTOT(endbuf);
1062                         end.cenlen = ENDSIZ(endbuf);
1063                         end.cenoff = ENDOFF(endbuf);
1064                         end.endpos = pos + i;
1065                         int comlen = ENDCOM(endbuf);
1066                         if (end.endpos + ENDHDR + comlen != ziplen) {
1067                             // ENDSIG matched, however the size of file comment in it does
1068                             // not match the real size. One "common" cause for this problem
1069                             // is some "extra" bytes are padded at the end of the zipfile.
1070                             // Let's do some extra verification, we don't care about the
1071                             // performance in this situation.
1072                             byte[] sbuf = new byte[4];
1073                             long cenpos = end.endpos - end.cenlen;
1074                             long locpos = cenpos - end.cenoff;
1075                             if  (cenpos < 0 ||
1076                                  locpos < 0 ||
1077                                  readFullyAt(sbuf, 0, sbuf.length, cenpos) != 4 ||
1078                                  GETSIG(sbuf) != CENSIG ||
1079                                  readFullyAt(sbuf, 0, sbuf.length, locpos) != 4 ||
1080                                  GETSIG(sbuf) != LOCSIG) {
1081                                 continue;
1082                             }
1083                         }
1084                         if (comlen > 0) {    // this zip file has comlen
1085                             comment = new byte[comlen];
1086                             if (readFullyAt(comment, 0, comlen, end.endpos + ENDHDR) != comlen) {
1087                                 zerror("zip comment read failed");
1088                             }
1089                         }
1090                         if (end.cenlen == ZIP64_MAGICVAL ||
1091                             end.cenoff == ZIP64_MAGICVAL ||
1092                             end.centot == ZIP64_MAGICCOUNT)
1093                         {
1094                             // need to find the zip64 end;
1095                             try {
1096                                 byte[] loc64 = new byte[ZIP64_LOCHDR];
1097                                 if (readFullyAt(loc64, 0, loc64.length, end.endpos - ZIP64_LOCHDR)
1098                                     != loc64.length || GETSIG(loc64) != ZIP64_LOCSIG) {
1099                                     return end;
1100                                 }
1101                                 long end64pos = ZIP64_LOCOFF(loc64);
1102                                 byte[] end64buf = new byte[ZIP64_ENDHDR];
1103                                 if (readFullyAt(end64buf, 0, end64buf.length, end64pos)
1104                                     != end64buf.length || GETSIG(end64buf) != ZIP64_ENDSIG) {
1105                                     return end;
1106                                 }
1107                                 // end64 found, re-calcualte everything.
1108                                 end.cenlen = ZIP64_ENDSIZ(end64buf);
1109                                 end.cenoff = ZIP64_ENDOFF(end64buf);
1110                                 end.centot = (int)ZIP64_ENDTOT(end64buf); // assume total < 2g
1111                                 end.endpos = end64pos;
1112                             } catch (IOException x) {}    // no zip64 loc/end
1113                         }
1114                         return end;
1115                     }
1116                 }
1117             }
1118             zerror("zip END header not found");
1119             return null; //make compiler happy
1120         }
1121 
1122         // Reads zip file central directory.
1123         private void initCEN(int knownTotal) throws IOException {
1124             if (knownTotal == -1) {
1125                 End end = findEND();
1126                 if (end.endpos == 0) {
1127                     locpos = 0;
1128                     total = 0;
1129                     entries  = new int[0];
1130                     cen = null;
1131                     return;         // only END header present
1132                 }
1133                 if (end.cenlen > end.endpos)
1134                     zerror("invalid END header (bad central directory size)");
1135                 long cenpos = end.endpos - end.cenlen;     // position of CEN table
1136                 // Get position of first local file (LOC) header, taking into
1137                 // account that there may be a stub prefixed to the zip file.
1138                 locpos = cenpos - end.cenoff;
1139                 if (locpos < 0) {
1140                     zerror("invalid END header (bad central directory offset)");
1141                 }
1142                 // read in the CEN and END
1143                 cen = new byte[(int)(end.cenlen + ENDHDR)];
1144                 if (readFullyAt(cen, 0, cen.length, cenpos) != end.cenlen + ENDHDR) {
1145                     zerror("read CEN tables failed");
1146                 }
1147                 total = end.centot;
1148             } else {
1149                 total = knownTotal;
1150             }
1151             // hash table for entries
1152             entries  = new int[total * 3];
1153             tablelen = ((total/2) | 1); // Odd -> fewer collisions
1154             table    =  new int[tablelen];
1155             Arrays.fill(table, ZIP_ENDCHAIN);
1156             int idx = 0;
1157             int hash = 0;
1158             int next = -1;
1159 
1160             // list for all meta entries
1161             metanames = new ArrayList<>();
1162 
1163             // Iterate through the entries in the central directory
1164             int i = 0;
1165             int hsh = 0;
1166             int pos = 0;
1167             int limit = cen.length - ENDHDR;
1168             while (pos + CENHDR  <= limit) {
1169                 if (i >= total) {
1170                     // This will only happen if the zip file has an incorrect
1171                     // ENDTOT field, which usually means it contains more than
1172                     // 65535 entries.
1173                     initCEN(countCENHeaders(cen, limit));
1174                     return;
1175                 }
1176                 if (CENSIG(cen, pos) != CENSIG)
1177                     zerror("invalid CEN header (bad signature)");
1178                 int method = CENHOW(cen, pos);
1179                 int nlen   = CENNAM(cen, pos);
1180                 int elen   = CENEXT(cen, pos);
1181                 int clen   = CENCOM(cen, pos);
1182                 if ((CENFLG(cen, pos) & 1) != 0)
1183                     zerror("invalid CEN header (encrypted entry)");
1184                 if (method != STORED && method != DEFLATED)
1185                     zerror("invalid CEN header (bad compression method: " + method + ")");
1186                 if (pos + CENHDR + nlen > limit)
1187                     zerror("invalid CEN header (bad header size)");
1188                 // Record the CEN offset and the name hash in our hash cell.
1189                 hash = hashN(cen, pos + CENHDR, nlen);
1190                 hsh = (hash & 0x7fffffff) % tablelen;
1191                 next = table[hsh];
1192                 table[hsh] = idx;
1193                 idx = addEntry(idx, hash, next, pos);
1194                 // Adds name to metanames.
1195                 if (isMetaName(cen, pos + CENHDR, nlen)) {
1196                     metanames.add(pos);
1197                 }
1198                 // skip ext and comment
1199                 pos += (CENHDR + nlen + elen + clen);
1200                 i++;
1201             }
1202             total = i;
1203             if (pos + ENDHDR != cen.length) {
1204                 zerror("invalid CEN header (bad header size)");
1205             }
1206         }
1207 
1208         private static void zerror(String msg) throws ZipException {
1209             throw new ZipException(msg);
1210         }
1211 
1212         /*
1213          * Returns the {@code pos} of the zip cen entry corresponding to the
1214          * specified entry name, or -1 if not found.
1215          */
1216         private int getEntryPos(byte[] name, boolean addSlash) {
1217             if (total == 0) {
1218                 return -1;
1219             }
1220             int hsh = hashN(name, 0, name.length);
1221             int idx = table[(hsh & 0x7fffffff) % tablelen];
1222             /*
1223              * This while loop is an optimization where a double lookup
1224              * for name and name+/ is being performed. The name char
1225              * array has enough room at the end to try again with a
1226              * slash appended if the first table lookup does not succeed.
1227              */
1228             while(true) {
1229                 /*
1230                  * Search down the target hash chain for a entry whose
1231                  * 32 bit hash matches the hashed name.
1232                  */
1233                 while (idx != ZIP_ENDCHAIN) {
1234                     if (getEntryHash(idx) == hsh) {
1235                         // The CEN name must match the specfied one
1236                         int pos = getEntryPos(idx);
1237                         if (name.length == CENNAM(cen, pos)) {
1238                             boolean matched = true;
1239                             int nameoff = pos + CENHDR;
1240                             for (int i = 0; i < name.length; i++) {
1241                                 if (name[i] != cen[nameoff++]) {
1242                                     matched = false;
1243                                     break;
1244                                 }
1245                             }
1246                             if (matched) {
1247                                 return pos;
1248                             }
1249                          }
1250                     }
1251                     idx = getEntryNext(idx);
1252                 }
1253                 /* If not addSlash, or slash is already there, we are done */
1254                 if (!addSlash  || name[name.length - 1] == '/') {
1255                      return -1;
1256                 }
1257                 /* Add slash and try once more */
1258                 name = Arrays.copyOf(name, name.length + 1);
1259                 name[name.length - 1] = '/';
1260                 hsh = hash_append(hsh, (byte)'/');
1261                 //idx = table[hsh % tablelen];
1262                 idx = table[(hsh & 0x7fffffff) % tablelen];
1263                 addSlash = false;
1264             }
1265         }
1266 
1267         private static byte[] metainf = new byte[] {
1268             'M', 'E', 'T', 'A', '-', 'I' , 'N', 'F', '/',
1269         };
1270 
1271         /*
1272          * Returns true if the specified entry's name begins with the string
1273          * "META-INF/" irrespective of case.
1274          */
1275         private static boolean isMetaName(byte[] name,  int off, int len) {
1276             if (len < 9 || (name[off] != 'M' && name[off] != 'm')) {  //  sizeof("META-INF/") - 1
1277                 return false;
1278             }
1279             off++;
1280             for (int i = 1; i < metainf.length; i++) {
1281                 byte c = name[off++];
1282                 // Avoid toupper; it's locale-dependent
1283                 if (c >= 'a' && c <= 'z') {
1284                     c += 'A' - 'a';
1285                 }
1286                 if (metainf[i] != c) {
1287                     return false;
1288                 }
1289             }
1290             return true;
1291         }
1292 
1293         /*
1294          * Counts the number of CEN headers in a central directory extending
1295          * from BEG to END.  Might return a bogus answer if the zip file is
1296          * corrupt, but will not crash.
1297          */
1298         static int countCENHeaders(byte[] cen, int end) {
1299             int count = 0;
1300             int pos = 0;
1301             while (pos + CENHDR <= end) {
1302                 count++;
1303                 pos += (CENHDR + CENNAM(cen, pos) + CENEXT(cen, pos) + CENCOM(cen, pos));
1304             }
1305             return count;
1306         }
1307     }
1308 }