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Java example source code file (EntriesOrder.java)

This example Java source code file (EntriesOrder.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

certificate, exception, iterable, iterator, jar, jarentry, jarfile, jarinputstream, linkedlist, list, meta-inf, meta\-inf\/inf, override, string, util, zip, zipoutputstream

The EntriesOrder.java Java example source code

/*
 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/**
 * @test
 * @bug 8031572
 * @summary jarsigner -verify exits with 0 when a jar file is not properly signed
 */

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.security.cert.Certificate;
import java.util.*;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.jar.JarInputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

public class EntriesOrder {

    public static void main(String[] args) throws Exception {

        String[] entries = {
                "META-INF/",
                "META-INF/MANIFEST.MF",
                "META-INF/A.RSA",
                "META-INF/A.SF",
                "META-INF/inf",
                "a"};

        Map<String,byte[]> content = new HashMap<>();

        // We will create a jar containing entries above. Try all permutations
        // and confirm 1) When opened as a JarFile, we can always get 3 signed
        // ones (MANIFEST, inf, a), and 2) When opened as a JarInputStream,
        // when the order is correct (MANIFEST at beginning, followed by RSA/SF,
        // directory ignored), we can get 2 signed ones (inf, a).

        // Prepares raw files
        Files.write(Paths.get("a"), "a".getBytes());
        Files.createDirectory(Paths.get("META-INF/"));
        Files.write(Paths.get("META-INF/inf"), "inf".getBytes());

        // Pack, sign, and extract to get all files
        sun.tools.jar.Main m =
                new sun.tools.jar.Main(System.out, System.err, "jar");
        if (!m.run("cvf a.jar a META-INF/inf".split(" "))) {
            throw new Exception("jar creation failed");
        }
        sun.security.tools.keytool.Main.main(
                ("-keystore jks -storepass changeit -keypass changeit -dname" +
                        " CN=A -alias a -genkeypair -keyalg rsa").split(" "));
        sun.security.tools.jarsigner.Main.main(
                "-keystore jks -storepass changeit a.jar a".split(" "));
        m = new sun.tools.jar.Main(System.out, System.err, "jar");
        if (!m.run("xvf a.jar".split(" "))) {
            throw new Exception("jar extraction failed");
        }

        // Data
        for (String s: entries) {
            if (!s.endsWith("/")) {
                content.put(s, Files.readAllBytes(Paths.get(s)));
            }
        }

        // Test
        for (List<String> perm: Permute(entries)) {

            // Recreate a jar
            try (ZipOutputStream zos
                         = new ZipOutputStream(new FileOutputStream("x.jar"))) {
                for (String e: perm) {
                    zos.putNextEntry(new ZipEntry(e));
                    if (Paths.get(e).toFile().isDirectory()) continue;
                    zos.write(content.get(e));
                }
            }

            // Open with JarFile, number of signed entries should be 3.
            int cc = 0;
            try (JarFile jf = new JarFile("x.jar")) {
                Enumeration<JarEntry> jes = jf.entries();
                while (jes.hasMoreElements()) {
                    JarEntry je = jes.nextElement();
                    sun.misc.IOUtils.readFully(jf.getInputStream(je), -1, true);
                    Certificate[] certs = je.getCertificates();
                    if (certs != null && certs.length > 0) {
                        cc++;
                    }
                }
            }

            if (cc != 3) {
                System.out.println(perm + " - jf - " + cc);
                throw new Exception();
            }

            // Open with JarInputStream
            int signed;

            perm.remove("META-INF/");
            if (perm.get(0).equals("META-INF/MANIFEST.MF") &&
                    perm.get(1).contains("/A.") &&
                    perm.get(2).contains("/A.")) {
                signed = 2;     // Good order
            } else {
                signed = 0;     // Bad order. In this case, the number of signed
                                // entries is not documented. Just test impl.
            }

            cc = 0;
            try (JarInputStream jis
                         = new JarInputStream(new FileInputStream("x.jar"))) {
                while (true) {
                    JarEntry je = jis.getNextJarEntry();
                    if (je == null) break;
                    sun.misc.IOUtils.readFully(jis, -1, true);
                    Certificate[] certs = je.getCertificates();
                    if (certs != null && certs.length > 0) {
                        cc++;
                    }
                }
            }

            if (cc != signed) {
                System.out.println(perm + " - jis - " + cc + " " + signed);
                throw new Exception();
            }
        }
    }

    // Helper method to return all permutations of an array. Each output can
    // be altered without damaging the iteration process.
    static Iterable<List Permute(String[] entries) {
        return new Iterable<List() {

            int s = entries.length;
            long c = factorial(s) - 1;      // number of permutations

            private long factorial(int n) {
                return (n == 1) ? 1: (n * factorial(n-1));
            }

            @Override
            public Iterator<List iterator() {
                return new Iterator<List() {
                    @Override
                    public boolean hasNext() {
                        return c >= 0;
                    }

                    @Override
                    public List<String> next() {
                        if (c < 0) return null;
                        List<String> result = new ArrayList<>(s);
                        LinkedList<String> source = new LinkedList<>(
                                Arrays.asList(entries));
                        // Treat c as a integer with different radixes at
                        // different digits, i.e. at digit 0, radix is s;
                        // at digit 1, radix is s-1. Thus a s-digit number
                        // is able to represent s! different values.
                        long n = c;
                        for (int i=s; i>=1; i--) {
                            int x = (int)(n % i);
                            result.add(source.remove(x));
                            n = n / i;
                        }
                        c--;
                        return result;
                    }
                };
            }
        };
    }
}

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