/*

 * Copyright 1997-2009 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package java.util.jar;

import java.io.*;

import java.lang.ref.SoftReference;

import java.util.*;

import java.util.zip.*;

import java.security.CodeSigner;

import java.security.cert.Certificate;

import java.security.AccessController;

import sun.security.action.GetPropertyAction;

import sun.security.util.ManifestEntryVerifier;

import sun.misc.SharedSecrets;

/**

 * The <code>JarFile</code> class is used to read the contents of a jar file

 * from any file that can be opened with <code>java.io.RandomAccessFile</code>.

 * It extends the class <code>java.util.zip.ZipFile</code> with support

 * for reading an optional <code>Manifest</code> entry. The

 * <code>Manifest</code> can be used to specify meta-information about the

 * jar file and its entries.

 *

 * <p> Unless otherwise noted, passing a <tt>null</tt> argument to a constructor

 * or method in this class will cause a {@link NullPointerException} to be

 * thrown.

 *

 * @author  David Connelly

 * @see     Manifest

 * @see     java.util.zip.ZipFile

 * @see     java.util.jar.JarEntry

 * @since   1.2

 */

public

class JarFile extends ZipFile {

    private SoftReference<Manifest> manRef;

    private JarEntry manEntry;

    private JarVerifier jv;

    private boolean jvInitialized;

    private boolean verify;

    private boolean computedHasClassPathAttribute;

    private boolean hasClassPathAttribute;

    // Set up JavaUtilJarAccess in SharedSecrets

    static {

        SharedSecrets.setJavaUtilJarAccess(new JavaUtilJarAccessImpl());

    }

    /**

     * The JAR manifest file name.

     */

    public static final String MANIFEST_NAME = "META-INF/MANIFEST.MF";

    /**

     * Creates a new <code>JarFile</code> to read from the specified

     * file <code>name</code>. The <code>JarFile</code> will be verified if

     * it is signed.

     * @param name the name of the jar file to be opened for reading

     * @throws IOException if an I/O error has occurred

     * @throws SecurityException if access to the file is denied

     *         by the SecurityManager

     */

    public JarFile(String name) throws IOException {

        this(new File(name), true, ZipFile.OPEN_READ);

    }

    /**

     * Creates a new <code>JarFile</code> to read from the specified

     * file <code>name</code>.

     * @param name the name of the jar file to be opened for reading

     * @param verify whether or not to verify the jar file if

     * it is signed.

     * @throws IOException if an I/O error has occurred

     * @throws SecurityException if access to the file is denied

     *         by the SecurityManager

     */

    public JarFile(String name, boolean verify) throws IOException {

        this(new File(name), verify, ZipFile.OPEN_READ);

    }

    /**

     * Creates a new <code>JarFile</code> to read from the specified

     * <code>File</code> object. The <code>JarFile</code> will be verified if

     * it is signed.

     * @param file the jar file to be opened for reading

     * @throws IOException if an I/O error has occurred

     * @throws SecurityException if access to the file is denied

     *         by the SecurityManager

     */

    public JarFile(File file) throws IOException {

        this(file, true, ZipFile.OPEN_READ);

    }

    /**

     * Creates a new <code>JarFile</code> to read from the specified

     * <code>File</code> object.

     * @param file the jar file to be opened for reading

     * @param verify whether or not to verify the jar file if

     * it is signed.

     * @throws IOException if an I/O error has occurred

     * @throws SecurityException if access to the file is denied

     *         by the SecurityManager.

     */

    public JarFile(File file, boolean verify) throws IOException {

        this(file, verify, ZipFile.OPEN_READ);

    }

    /**

     * Creates a new <code>JarFile</code> to read from the specified

     * <code>File</code> object in the specified mode.  The mode argument

     * must be either <tt>OPEN_READ</tt> or <tt>OPEN_READ | OPEN_DELETE</tt>.

     *

     * @param file the jar file to be opened for reading

     * @param verify whether or not to verify the jar file if

     * it is signed.

     * @param mode the mode in which the file is to be opened

     * @throws IOException if an I/O error has occurred

     * @throws IllegalArgumentException

     *         if the <tt>mode</tt> argument is invalid

     * @throws SecurityException if access to the file is denied

     *         by the SecurityManager

     * @since 1.3

     */

    public JarFile(File file, boolean verify, int mode) throws IOException {

        super(file, mode);

        this.verify = verify;

    }

    /**

     * Returns the jar file manifest, or <code>null</code> if none.

     *

     * @return the jar file manifest, or <code>null</code> if none

     *

     * @throws IllegalStateException

     *         may be thrown if the jar file has been closed

     */

    public Manifest getManifest() throws IOException {

        return getManifestFromReference();

    }

    private Manifest getManifestFromReference() throws IOException {

        Manifest man = manRef != null ? manRef.get() : null;

        if (man == null) {

            JarEntry manEntry = getManEntry();

            // If found then load the manifest

            if (manEntry != null) {

                if (verify) {

                    byte[] b = getBytes(manEntry);

                    man = new Manifest(new ByteArrayInputStream(b));

                    if (!jvInitialized) {

                        jv = new JarVerifier(b);

                    }

                } else {

                    man = new Manifest(super.getInputStream(manEntry));

                }

                manRef = new SoftReference(man);

            }

        }

        return man;

    }

    private native String[] getMetaInfEntryNames();

    /**

     * Returns the <code>JarEntry</code> for the given entry name or

     * <code>null</code> if not found.

     *

     * @param name the jar file entry name

     * @return the <code>JarEntry</code> for the given entry name or

     *         <code>null</code> if not found.

     *

     * @throws IllegalStateException

     *         may be thrown if the jar file has been closed

     *

     * @see java.util.jar.JarEntry

     */

    public JarEntry getJarEntry(String name) {

        return (JarEntry)getEntry(name);

    }

    /**

     * Returns the <code>ZipEntry</code> for the given entry name or

     * <code>null</code> if not found.

     *

     * @param name the jar file entry name

     * @return the <code>ZipEntry</code> for the given entry name or

     *         <code>null</code> if not found

     *

     * @throws IllegalStateException

     *         may be thrown if the jar file has been closed

     *

     * @see java.util.zip.ZipEntry

     */

    public ZipEntry getEntry(String name) {

        ZipEntry ze = super.getEntry(name);

        if (ze != null) {

            return new JarFileEntry(ze);

        }

        return null;

    }

    /**

     * Returns an enumeration of the zip file entries.

     */

    public Enumeration<JarEntry> entries() {

        final Enumeration enum_ = super.entries();

        return new Enumeration<JarEntry>() {

            public boolean hasMoreElements() {

                return enum_.hasMoreElements();

            }

            public JarFileEntry nextElement() {

                ZipEntry ze = (ZipEntry)enum_.nextElement();

                return new JarFileEntry(ze);

            }

        };

    }

    private class JarFileEntry extends JarEntry {

        JarFileEntry(ZipEntry ze) {

            super(ze);

        }

        public Attributes getAttributes() throws IOException {

            Manifest man = JarFile.this.getManifest();

            if (man != null) {

                return man.getAttributes(getName());

            } else {

                return null;

            }

        }

        public Certificate[] getCertificates() {

            try {

                maybeInstantiateVerifier();

            } catch (IOException e) {

                throw new RuntimeException(e);

            }

            if (certs == null && jv != null) {

                certs = jv.getCerts(getName());

            }

            return certs == null ? null : certs.clone();

        }

        public CodeSigner[] getCodeSigners() {

            try {

                maybeInstantiateVerifier();

            } catch (IOException e) {

                throw new RuntimeException(e);

            }

            if (signers == null && jv != null) {

                signers = jv.getCodeSigners(getName());

            }

            return signers == null ? null : signers.clone();

        }

    }

    /*

     * Ensures that the JarVerifier has been created if one is

     * necessary (i.e., the jar appears to be signed.) This is done as

     * a quick check to avoid processing of the manifest for unsigned

     * jars.

     */

    private void maybeInstantiateVerifier() throws IOException {

        if (jv != null) {

            return;

        }

        if (verify) {

            String[] names = getMetaInfEntryNames();

            if (names != null) {

                for (int i = 0; i < names.length; i++) {

                    String name = names[i].toUpperCase(Locale.ENGLISH);

                    if (name.endsWith(".DSA") ||

                        name.endsWith(".RSA") ||

                        name.endsWith(".EC") ||

                        name.endsWith(".SF")) {

                        // Assume since we found a signature-related file

                        // that the jar is signed and that we therefore

                        // need a JarVerifier and Manifest

                        getManifest();

                        return;

                    }

                }

            }

            // No signature-related files; don't instantiate a

            // verifier

            verify = false;

        }

    }

    /*

     * Initializes the verifier object by reading all the manifest

     * entries and passing them to the verifier.

     */

    private void initializeVerifier() {

        ManifestEntryVerifier mev = null;

        // Verify "META-INF/" entries...

        try {

            String[] names = getMetaInfEntryNames();

            if (names != null) {

                for (int i = 0; i < names.length; i++) {

                    JarEntry e = getJarEntry(names[i]);

                    if (!e.isDirectory()) {

                        if (mev == null) {

                            mev = new ManifestEntryVerifier

                                (getManifestFromReference());

                        }

                        byte[] b = getBytes(e);

                        if (b != null && b.length > 0) {

                            jv.beginEntry(e, mev);

                            jv.update(b.length, b, 0, b.length, mev);

                            jv.update(-1, null, 0, 0, mev);

                        }

                    }

                }

            }

        } catch (IOException ex) {

            // if we had an error parsing any blocks, just

            // treat the jar file as being unsigned

            jv = null;

            verify = false;

        }

        // if after initializing the verifier we have nothing

        // signed, we null it out.

        if (jv != null) {

            jv.doneWithMeta();

            if (JarVerifier.debug != null) {

                JarVerifier.debug.println("done with meta!");

            }

            if (jv.nothingToVerify()) {

                if (JarVerifier.debug != null) {

                    JarVerifier.debug.println("nothing to verify!");

                }

                jv = null;

                verify = false;

            }

        }

    }

    /*

     * Reads all the bytes for a given entry. Used to process the

     * META-INF files.

     */

    private byte[] getBytes(ZipEntry ze) throws IOException {

        byte[] b = new byte[(int)ze.getSize()];

        DataInputStream is = new DataInputStream(super.getInputStream(ze));

        is.readFully(b, 0, b.length);

        is.close();

        return b;

    }

    /**

     * Returns an input stream for reading the contents of the specified

     * zip file entry.

     * @param ze the zip file entry

     * @return an input stream for reading the contents of the specified

     *         zip file entry

     * @throws ZipException if a zip file format error has occurred

     * @throws IOException if an I/O error has occurred

     * @throws SecurityException if any of the jar file entries

     *         are incorrectly signed.

     * @throws IllegalStateException

     *         may be thrown if the jar file has been closed

     */

    public synchronized InputStream getInputStream(ZipEntry ze)

        throws IOException

    {

        maybeInstantiateVerifier();

        if (jv == null) {

            return super.getInputStream(ze);

        }

        if (!jvInitialized) {

            initializeVerifier();

            jvInitialized = true;

            // could be set to null after a call to

            // initializeVerifier if we have nothing to

            // verify

            if (jv == null)

                return super.getInputStream(ze);

        }

        // wrap a verifier stream around the real stream

        return new JarVerifier.VerifierStream(

            getManifestFromReference(),

            ze instanceof JarFileEntry ?

            (JarEntry) ze : getJarEntry(ze.getName()),

            super.getInputStream(ze),

            jv);

    }

    // Statics for hand-coded Boyer-Moore search in hasClassPathAttribute()

    // The bad character shift for "class-path"

    private static int[] lastOcc;

    // The good suffix shift for "class-path"

    private static int[] optoSft;

    // Initialize the shift arrays to search for "class-path"

    private static char[] src = {'c','l','a','s','s','-','p','a','t','h'};

    static {

        lastOcc = new int[128];

        optoSft = new int[10];

        lastOcc[(int)'c']=1;

        lastOcc[(int)'l']=2;

        lastOcc[(int)'s']=5;

        lastOcc[(int)'-']=6;

        lastOcc[(int)'p']=7;

        lastOcc[(int)'a']=8;

        lastOcc[(int)'t']=9;

        lastOcc[(int)'h']=10;

        for (int i=0; i<9; i++)

            optoSft[i]=10;

        optoSft[9]=1;

    }

    private JarEntry getManEntry() {

        if (manEntry == null) {

            // First look up manifest entry using standard name

            manEntry = getJarEntry(MANIFEST_NAME);

            if (manEntry == null) {

                // If not found, then iterate through all the "META-INF/"

                // entries to find a match.

                String[] names = getMetaInfEntryNames();

                if (names != null) {

                    for (int i = 0; i < names.length; i++) {

                        if (MANIFEST_NAME.equals(

                                                 names[i].toUpperCase(Locale.ENGLISH))) {

                            manEntry = getJarEntry(names[i]);

                            break;

                        }

                    }

                }

            }

        }

        return manEntry;

    }

    // Returns true iff this jar file has a manifest with a class path

    // attribute. Returns false if there is no manifest or the manifest

    // does not contain a "Class-Path" attribute. Currently exported to

    // core libraries via sun.misc.SharedSecrets.

    boolean hasClassPathAttribute() throws IOException {

        if (computedHasClassPathAttribute) {

            return hasClassPathAttribute;

        }

        hasClassPathAttribute = false;

        if (!isKnownToNotHaveClassPathAttribute()) {

            JarEntry manEntry = getManEntry();

            if (manEntry != null) {

                byte[] b = new byte[(int)manEntry.getSize()];

                DataInputStream dis = new DataInputStream(

                                                          super.getInputStream(manEntry));

                dis.readFully(b, 0, b.length);

                dis.close();

                int last = b.length - src.length;

                int i = 0;

                next:

                while (i<=last) {

                    for (int j=9; j>=0; j--) {

                        char c = (char) b[i+j];

                        c = (((c-'A')|('Z'-c)) >= 0) ? (char)(c + 32) : c;

                        if (c != src[j]) {

                            i += Math.max(j + 1 - lastOcc[c&0x7F], optoSft[j]);

                            continue next;

                        }

                    }

                    hasClassPathAttribute = true;

                    break;

                }

            }

        }

        computedHasClassPathAttribute = true;

        return hasClassPathAttribute;

    }

    private static String javaHome;

    private static String[] jarNames;

    private boolean isKnownToNotHaveClassPathAttribute() {

        // Optimize away even scanning of manifest for jar files we

        // deliver which don't have a class-path attribute. If one of

        // these jars is changed to include such an attribute this code

        // must be changed.

        if (javaHome == null) {

            javaHome = AccessController.doPrivileged(

                new GetPropertyAction("java.home"));

        }

        if (jarNames == null) {

            String[] names = new String[10];

            String fileSep = File.separator;

            int i = 0;

            names[i++] = fileSep + "rt.jar";

            names[i++] = fileSep + "sunrsasign.jar";

            names[i++] = fileSep + "jsse.jar";

            names[i++] = fileSep + "jce.jar";

            names[i++] = fileSep + "charsets.jar";

            names[i++] = fileSep + "dnsns.jar";

            names[i++] = fileSep + "ldapsec.jar";