package org.mortbay.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.security.Key;
import java.security.KeyStore;
import java.security.cert.Certificate;
import java.security.cert.X509Certificate;
import java.util.Enumeration;

/**
 * This class can be used to import a key/certificate pair from a pkcs12 file
 * into a regular JKS format keystore for use with jetty and other java based
 * SSL applications, etc. 
 *<PRE>
 *    usage: java PKCS12Import {pkcs12file} [newjksfile]
 *</PRE>
 *
 * If you don't supply newjksfile, newstore.jks will be used.  This can be an
 * existing JKS keystore.
 * <P>
 * Upon execution, you will be prompted for the password for the pkcs12 keystore
 * as well as the password for the jdk file.  After execution you should have a
 * JKS keystore file that contains the private key and certificate that were in
 * the pkcs12
 * <P>
 * You can generate a pkcs12 file from PEM encoded certificate and key files
 * using the following openssl command:
 * <PRE>
 *    openssl pkcs12 -export -out keystore.pkcs12 -in www.crt -inkey www.key
 * </PRE>
 * then run:
 * <PRE>
 *    java PKCS12Import keystore.pkcs12 keytore.jks
 * </PRE>
 *
 * @author Jason Gilbert &lt;jason@doozer.com&gt;
 */
public class PKCS12Import
{
   public static void main(String[] args) throws Exception
   {
      if (args.length < 1) {
         System.err.println(
               "usage: java PKCS12Import {pkcs12file} [newjksfile]");
         System.exit(1);
      }

      File fileIn = new File(args[0]);
      File fileOut;
      if (args.length > 1) {
         fileOut = new File(args[1]);
      } else {
         fileOut = new File("newstore.jks");
      }

      if (!fileIn.canRead()) {
         System.err.println(
               "Unable to access input keystore: " + fileIn.getPath());
         System.exit(2);
      }

      if (fileOut.exists() && !fileOut.canWrite()) {
         System.err.println(
               "Output file is not writable: " + fileOut.getPath());
         System.exit(2);
      }

      KeyStore kspkcs12 = KeyStore.getInstance("pkcs12");
      KeyStore ksjks = KeyStore.getInstance("jks");

      System.out.print("Enter input keystore passphrase: ");
      char[] inphrase = readPassphrase();
      System.out.print("Enter output keystore passphrase: ");
      char[] outphrase = readPassphrase();

      kspkcs12.load(new FileInputStream(fileIn), inphrase);

      ksjks.load(
            (fileOut.exists())
            ? new FileInputStream(fileOut) : null, outphrase);

      Enumeration eAliases = kspkcs12.aliases();
      int n = 0;
      while (eAliases.hasMoreElements()) {
         String strAlias = (String)eAliases.nextElement();
         System.err.println("Alias " + n++ + ": " + strAlias);

         if (kspkcs12.isKeyEntry(strAlias)) {
            System.err.println("Adding key for alias " + strAlias);
            Key key = kspkcs12.getKey(strAlias, inphrase);

            Certificate[] chain = kspkcs12.getCertificateChain(strAlias);

            ksjks.setKeyEntry(strAlias, key, outphrase, chain);
         }
      }

      OutputStream out = new FileOutputStream(fileOut);
      ksjks.store(out, outphrase);
      out.close();
   }

   static void dumpChain(Certificate[] chain)
   {
      for (int i = 0; i < chain.length; i++) {
         Certificate cert = chain[i];
         if (cert instanceof X509Certificate) {
            X509Certificate x509 = (X509Certificate)chain[i];
            System.err.println("subject: " + x509.getSubjectDN());
            System.err.println("issuer: " + x509.getIssuerDN());
         }
      }
   }

   static char[] readPassphrase() throws IOException
   {
      InputStreamReader in = new InputStreamReader(System.in);

      char[] cbuf = new char[256];
      int i = 0;

readchars:
      while (i < cbuf.length) {
         char c = (char)in.read();
         switch (c) {
            case '\r':
               break readchars;
            case '\n':
               break readchars;
            default:
               cbuf[i++] = c;
         }
      }

      char[] phrase = new char[i];
      System.arraycopy(cbuf, 0, phrase, 0, i);
      return phrase;
   }
}

