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package java.util.jar;

import java.util.zip.*;
import java.io.*;
import sun.security.util.ManifestEntryVerifier;
import jdk.internal.util.jar.JarIndex;

The JarInputStream class is used to read the contents of
a JAR file from any input stream. It extends the class
java.util.zip.ZipInputStream with support for reading
an optional Manifest entry. The Manifest
can be used to store meta-information about the JAR file and its entries.
Author:
 David Connelly
See Also:
Manifest
ZipInputStream
Since:
  1.2/**
 * The <code>JarInputStream</code> class is used to read the contents of
 * a JAR file from any input stream. It extends the class
 * <code>java.util.zip.ZipInputStream</code> with support for reading
 * an optional <code>Manifest</code> entry. The <code>Manifest</code>
 * can be used to store meta-information about the JAR file and its entries.
 *
 * @author  David Connelly
 * @see     Manifest
 * @see     java.util.zip.ZipInputStream
 * @since   1.2
 */
public
class JarInputStream extends ZipInputStream {
    private Manifest man;
    private JarEntry first;
    private JarVerifier jv;
    private ManifestEntryVerifier mev;
    private final boolean doVerify;
    private boolean tryManifest;

    
Creates a new JarInputStream and reads the optional
manifest. If a manifest is present, also attempts to verify
the signatures if the JarInputStream is signed.
Params:
in – the actual input stream
Throws:
IOException – if an I/O error has occurred/**
     * Creates a new <code>JarInputStream</code> and reads the optional
     * manifest. If a manifest is present, also attempts to verify
     * the signatures if the JarInputStream is signed.
     * @param in the actual input stream
     * @exception IOException if an I/O error has occurred
     */
    public JarInputStream(InputStream in) throws IOException {
        this(in, true);
    }

    
Creates a new JarInputStream and reads the optional
manifest. If a manifest is present and verify is true, also attempts
to verify the signatures if the JarInputStream is signed.
Params:
in – the actual input stream
verify – whether or not to verify the JarInputStream if
it is signed.
Throws:
IOException – if an I/O error has occurred/**
     * Creates a new <code>JarInputStream</code> and reads the optional
     * manifest. If a manifest is present and verify is true, also attempts
     * to verify the signatures if the JarInputStream is signed.
     *
     * @param in the actual input stream
     * @param verify whether or not to verify the JarInputStream if
     * it is signed.
     * @exception IOException if an I/O error has occurred
     */
    public JarInputStream(InputStream in, boolean verify) throws IOException {
        super(in);
        this.doVerify = verify;

        // This implementation assumes the META-INF/MANIFEST.MF entry
        // should be either the first or the second entry (when preceded
        // by the dir META-INF/). It skips the META-INF/ and then
        // "consumes" the MANIFEST.MF to initialize the Manifest object.
        JarEntry e = (JarEntry)super.getNextEntry();
        if (e != null && e.getName().equalsIgnoreCase("META-INF/"))
            e = (JarEntry)super.getNextEntry();
        first = checkManifest(e);
    }

    private JarEntry checkManifest(JarEntry e)
        throws IOException
    {
        if (e != null && JarFile.MANIFEST_NAME.equalsIgnoreCase(e.getName())) {
            man = new Manifest();
            byte bytes[] = getBytes(new BufferedInputStream(this));
            man.read(new ByteArrayInputStream(bytes));
            closeEntry();
            if (doVerify) {
                jv = new JarVerifier(bytes);
                mev = new ManifestEntryVerifier(man);
            }
            return (JarEntry)super.getNextEntry();
        }
        return e;
    }

    private byte[] getBytes(InputStream is)
        throws IOException
    {
        byte[] buffer = new byte[8192];
        ByteArrayOutputStream baos = new ByteArrayOutputStream(2048);
        int n;
        while ((n = is.read(buffer, 0, buffer.length)) != -1) {
            baos.write(buffer, 0, n);
        }
        return baos.toByteArray();
    }

    
Returns the Manifest for this JAR file, or
null if none.
Returns:
the Manifest for this JAR file, or
        null if none./**
     * Returns the <code>Manifest</code> for this JAR file, or
     * <code>null</code> if none.
     *
     * @return the <code>Manifest</code> for this JAR file, or
     *         <code>null</code> if none.
     */
    public Manifest getManifest() {
        return man;
    }

    
Reads the next ZIP file entry and positions the stream at the
beginning of the entry data. If verification has been enabled,
any invalid signature detected while positioning the stream for
the next entry will result in an exception.
Throws:
ZipException – if a ZIP file error has occurred
IOException – if an I/O error has occurred
SecurityException – if any of the jar file entries
        are incorrectly signed./**
     * Reads the next ZIP file entry and positions the stream at the
     * beginning of the entry data. If verification has been enabled,
     * any invalid signature detected while positioning the stream for
     * the next entry will result in an exception.
     * @exception ZipException if a ZIP file error has occurred
     * @exception IOException if an I/O error has occurred
     * @exception SecurityException if any of the jar file entries
     *         are incorrectly signed.
     */
    public ZipEntry getNextEntry() throws IOException {
        JarEntry e;
        if (first == null) {
            e = (JarEntry)super.getNextEntry();
            if (tryManifest) {
                e = checkManifest(e);
                tryManifest = false;
            }
        } else {
            e = first;
            if (first.getName().equalsIgnoreCase(JarIndex.INDEX_NAME))
                tryManifest = true;
            first = null;
        }
        if (jv != null && e != null) {
            // At this point, we might have parsed all the meta-inf
            // entries and have nothing to verify. If we have
            // nothing to verify, get rid of the JarVerifier object.
            if (jv.nothingToVerify() == true) {
                jv = null;
                mev = null;
            } else {
                jv.beginEntry(e, mev);
            }
        }
        return e;
    }

    
Reads the next JAR file entry and positions the stream at the
beginning of the entry data. If verification has been enabled,
any invalid signature detected while positioning the stream for
the next entry will result in an exception.
Throws:
ZipException – if a ZIP file error has occurred
IOException – if an I/O error has occurred
SecurityException – if any of the jar file entries
        are incorrectly signed.
Returns:
the next JAR file entry, or null if there are no more entries/**
     * Reads the next JAR file entry and positions the stream at the
     * beginning of the entry data. If verification has been enabled,
     * any invalid signature detected while positioning the stream for
     * the next entry will result in an exception.
     * @return the next JAR file entry, or null if there are no more entries
     * @exception ZipException if a ZIP file error has occurred
     * @exception IOException if an I/O error has occurred
     * @exception SecurityException if any of the jar file entries
     *         are incorrectly signed.
     */
    public JarEntry getNextJarEntry() throws IOException {
        return (JarEntry)getNextEntry();
    }

    
Reads from the current JAR file entry into an array of bytes.
If len is not zero, the method
blocks until some input is available; otherwise, no
bytes are read and 0 is returned.
If verification has been enabled, any invalid signature
on the current entry will be reported at some point before the
end of the entry is reached.
Params:
b – the buffer into which the data is read
off – the start offset in the destination array b
len – the maximum number of bytes to read
Throws:
NullPointerException – If b is null.
IndexOutOfBoundsException – If off is negative,
len is negative, or len is greater than
b.length - off
ZipException – if a ZIP file error has occurred
IOException – if an I/O error has occurred
SecurityException – if any of the jar file entries
        are incorrectly signed.
Returns:
the actual number of bytes read, or -1 if the end of the
        entry is reached/**
     * Reads from the current JAR file entry into an array of bytes.
     * If <code>len</code> is not zero, the method
     * blocks until some input is available; otherwise, no
     * bytes are read and <code>0</code> is returned.
     * If verification has been enabled, any invalid signature
     * on the current entry will be reported at some point before the
     * end of the entry is reached.
     * @param b the buffer into which the data is read
     * @param off the start offset in the destination array <code>b</code>
     * @param len the maximum number of bytes to read
     * @return the actual number of bytes read, or -1 if the end of the
     *         entry is reached
     * @exception  NullPointerException If <code>b</code> is <code>null</code>.
     * @exception  IndexOutOfBoundsException If <code>off</code> is negative,
     * <code>len</code> is negative, or <code>len</code> is greater than
     * <code>b.length - off</code>
     * @exception ZipException if a ZIP file error has occurred
     * @exception IOException if an I/O error has occurred
     * @exception SecurityException if any of the jar file entries
     *         are incorrectly signed.
     */
    public int read(byte[] b, int off, int len) throws IOException {
        int n;
        if (first == null) {
            n = super.read(b, off, len);
        } else {
            n = -1;
        }
        if (jv != null) {
            jv.update(n, b, off, len, mev);
        }
        return n;
    }

    
Creates a new JarEntry (ZipEntry) for the
specified JAR file entry name. The manifest attributes of
the specified JAR file entry name will be copied to the new
JarEntry.
Params:
name – the name of the JAR/ZIP file entry
Returns:
the JarEntry object just created/**
     * Creates a new <code>JarEntry</code> (<code>ZipEntry</code>) for the
     * specified JAR file entry name. The manifest attributes of
     * the specified JAR file entry name will be copied to the new
     * <CODE>JarEntry</CODE>.
     *
     * @param name the name of the JAR/ZIP file entry
     * @return the <code>JarEntry</code> object just created
     */
    protected ZipEntry createZipEntry(String name) {
        JarEntry e = new JarEntry(name);
        if (man != null) {
            e.attr = man.getAttributes(name);
        }
        return e;
    }
}