1 /*
2  * Copyright (c) 2005, 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.
8  *
9  * This code is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
16  * 2 along with this work; if not, write to the Free Software Foundation,
17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20  * or visit www.oracle.com if you need additional information or have any
21  * questions.
22  */
23 
24 /* @test
25  * @bug 6334171
26  * @summary Test that zip file's data descriptor is written correctly.
27  */
28 
29 import java.io.*;
30 import java.util.*;
31 import java.util.zip.*;
32 
33 /**
34  * Bug 6252735 ZipEntry contains wasteful "temporary storage" fields introduced
35  * a regression.  The value of the general purpose flag bit in a LOC header is
36  * written incorrectly, because it is computed on stale data.
37  * <p>
38  * With the bug present, zipbytes2 is written incorrectly: when the LOC
39  * header is written, (flag(e) & 8) == 8.  This is correct: the data will be
40  * compressed, so we don't have data length, etc. yet; that should be written
41  * in the DataDescriptor after the data itself is written.  However, when the
42  * ZipOutputStream that wraps zipbytes2 is closed, the data length _is_
43  * available, therefore (flag(e) & 8) = 0), therefore the DataDescriptor is
44  * not written.  This is why, with the bug, zipbytes1.length == sizeof(ext
45  * header) + zipbytes2.length.
46  * <p>
47  * The result is an invalid LOC header in zipbytes2.  So when we again use
48  * copyZip, we attempt to read a data length not from the LOC header but from
49  * the non-existent EXT header, and at that position in the file is some
50  * arbitrary and incorrect value.
51  */
52 public class DataDescriptor {
copyZip(ZipInputStream in, ZipOutputStream out)53     static void copyZip(ZipInputStream in, ZipOutputStream out) throws IOException {
54         byte[] buffer = new byte[1 << 14];
55         for (ZipEntry ze; (ze = in.getNextEntry()) != null; ) {
56             out.putNextEntry(ze);
57             // When the bug is present, it shows up here.  The second call to
58             // copyZip will throw an exception while reading data.
59             for (int nr; 0 < (nr = in.read(buffer)); ) {
60                 out.write(buffer, 0, nr);
61             }
62         }
63         in.close();
64     }
65 
realMain(String[] args)66     private static void realMain(String[] args) throws Throwable {
67         // Create zip output in byte array zipbytes
68         ByteArrayOutputStream baos = new ByteArrayOutputStream();
69         ZipOutputStream zos = new ZipOutputStream(baos);
70         ZipEntry e = new ZipEntry("testdir/foo");
71         byte[] data = "entry data".getBytes("ASCII");
72         zos.putNextEntry(e);
73         zos.write(data);
74         zos.close();
75         byte[] zipbytes1 = baos.toByteArray();
76         int length1 = zipbytes1.length;
77         System.out.println("zip bytes pre-copy length=" + length1);
78 
79         // Make a ZipInputStream around zipbytes, and use
80         // copyZip to get a new byte array.
81         ZipInputStream zis =
82             new ZipInputStream(
83                 new ByteArrayInputStream(zipbytes1));
84         baos.reset();
85         zos = new ZipOutputStream(baos);
86         copyZip(zis, zos);
87         zos.close();
88         byte[] zipbytes2 = baos.toByteArray();
89         int length2 = zipbytes2.length;
90         // When the bug is present, pre- and post-copy lengths are different!
91         System.out.println("zip bytes post-copy length=" + length2);
92 
93         equal(length1, length2);
94         check(Arrays.equals(zipbytes1, zipbytes2));
95 
96         // Now use copyZip again on the bytes resulting from the previous
97         // copy.  When the bug is present, copyZip will get an exception this
98         // time.
99         baos.reset();
100         zos = new ZipOutputStream(baos);
101         copyZip(new ZipInputStream(new ByteArrayInputStream(zipbytes2)), zos);
102         zos.close();
103         byte[] zipbytes3 = baos.toByteArray();
104         int length3 = zipbytes3.length;
105         System.out.println("zip bytes post-copy length=" + length3);
106 
107         equal(length1, length3);
108         check(Arrays.equals(zipbytes1, zipbytes3));
109     }
110 
111     //--------------------- Infrastructure ---------------------------
112     static volatile int passed = 0, failed = 0;
pass()113     static void pass() {passed++;}
fail()114     static void fail() {failed++; Thread.dumpStack();}
fail(String msg)115     static void fail(String msg) {System.out.println(msg); fail();}
unexpected(Throwable t)116     static void unexpected(Throwable t) {failed++; t.printStackTrace();}
check(boolean cond)117     static void check(boolean cond) {if (cond) pass(); else fail();}
equal(Object x, Object y)118     static void equal(Object x, Object y) {
119         if (x == null ? y == null : x.equals(y)) pass();
120         else fail(x + " not equal to " + y);}
main(String[] args)121     public static void main(String[] args) throws Throwable {
122         try {realMain(args);} catch (Throwable t) {unexpected(t);}
123         System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
124         if (failed > 0) throw new AssertionError("Some tests failed");}
125 }
126