how to create signed and encrypted mail in java using bouncycastle provider - Java

Respected sir,
i am creating a file for creating an encrypted mail in java.here is my
code below.Sir the problem i am facing is

exception in thread "main" java.security.KeystoreException pkcs12 not
Found
at java.security.keystore.getInstance(Unknown source)
at createencryptedmail.main(CreateEncryptedMail.java 54)

when i am writing this
/*KeyStore ks = KeyStore.getInstance("PKCS12");
FileInputStream fis = new FileInputStream(args[0]);
ks.load(fis, args[1].toCharArray());
fis.close();
*/
in place of
KeyStore ks = KeyStore.getInstance("PKCS12", "BC");
ks.load(new FileInputStream(args[0]), args[1].toCharArray());
then the first error is replaced by the follwing error
exception in thread main org.bouncycastle.mail.smime.smimeexception
can't find algorithm
at org.bouncycastle.mail.smime.SMimeEnvelopedgenerator.make(SMimeEnvelopedGenerator.java
120)

at org.bouncycastle.mail.smime.SMimeEnvelopedgenerator.generate(SMimeEnvelopedGenerator.java
166)
at createEncryptedmail.main(CreateEncryptedMail.java 126)


finally i also set all the classpaths required for bouncycastle as
follows
C:\j2sdk1.4.2_01\jre\lib\rt.jar;.;D:\chandan\javamail-1.2\mail.jar;D:\chandanmail\jaf-1.0.2\activation.jar;.;C:\Documents
and Settings\Administrator\Desktop\Encrypted mail
downloads\bcmail-jdk14-124.jar;.;C:\j2sdk1.4.2_01\jre\lib\ext\bcprov-jdk14-124.jar

but sir i don't know what's the problem . i am in this problem from
last 18 days.please help me.if possible mail me a sample code for
signedmail and signedencryptedmail so that i will remain great full to
u.


Your sincerely chandan kumar



import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.security.KeyStore;
import java.security.cert.Certificate;
import java.security.cert.X509Certificate;
import java.util.Enumeration;
import java.util.Properties;

import javax.mail.Address;
import javax.mail.Message;
import javax.mail.Session;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;

import org.bouncycastle.mail.smime.SMIMEEnvelopedGenerator;
import java.security.*;
import org.bouncycastle.jce.provider.*;

/**
* a simple example that creates a single encrypted mail message.
* <p>
* The key store can be created using the class in
* org.bouncycastle.jce.examples.PKCS12Example - the program expects
only one
* key to be present in the key file.
* <p>
* Note: while this means that both the private key is available to
* the program, the private key is retrieved from the keystore only
for
* the purposes of locating the corresponding public key, in normal
circumstances
* you would only be doing this with a certificate available.
*/
public class CreateEncryptedMail
{
public static void main(
String args[])
throws Exception
{
if (args.length != 2)
{
System.err.println("usage: CreateEncryptedMail
pkcs12Keystore password");
System.exit(0);
}
if (java.security.Security.getProvider("BC") == null) {
System.out.println("Can't find BC - adding");
java.security.Security.addProvider(new
org.bouncycastle.jce.provider.BouncyCastleProvider());
}


//
// Open the key store
//
KeyStore ks = KeyStore.getInstance("PKCS12","BC");

ks.load(new FileInputStream(args[0]), args[1].toCharArray());

/*KeyStore ks = KeyStore.getInstance("PKCS12");
FileInputStream fis = new FileInputStream(args[0]);
ks.load(fis, args[1].toCharArray());
fis.close();
*/
Enumeration e = ks.aliases();
String keyAlias = null;

while (e.hasMoreElements())
{
String alias = (String)e.nextElement();

if (ks.isKeyEntry(alias))
{
keyAlias = alias;
}
}

if (keyAlias == null)
{
System.err.println("can't find a private key!");
System.exit(0);
}

Certificate[] chain = ks.getCertificateChain(keyAlias);

//
// create the generator for creating an smime/encrypted
message
//
SMIMEEnvelopedGenerator gen = new SMIMEEnvelopedGenerator();

gen.addKeyTransRecipient((X509Certificate)chain[0]);

//
// create a subject key id - this has to be done the same way
as
// it is done in the certificate associated with the private
key
// version 3 only.
//
/*
MessageDigest dig =
MessageDigest.getInstance("SHA1", "BC");

dig.update(cert.getPublicKey().getEncoded());

gen.addKeyTransRecipient(cert.getPublicKey(), dig.digest());
*/

//
// create the base for our message
//
MimeBodyPart msg = new MimeBodyPart();

msg.setText("Hello world!");

//java.security.Security.insertProviderAt(new
org.bouncycastle.jce.provider.BouncyCastleProvider(), 6);

//MimeBodyPart mp = gen.generate(msg,SMIMEEnvelopedGenerator.DES_EDE3_CBC,"BC");
// MimeBodyPart mp = gen.generate(msg,
SMIMEEnvelopedGenerator.RC2_CBC, "BC");


// MimeBodyPart mp = gen.generate(msg,
SMIMEEnvelopedGenerator.IDEA_CBC, "BC");
// MimeBodyPart mp = gen.generate(msg,
SMIMEEnvelopedGenerator.DES_EDE3_CBC, "BC");
// MimeBodyPart mp = gen.generate(msg,
SMIMEEnvelopedGenerator.CAST5_CBC, "BC");
// MimeBodyPart mp = gen.generate(msg,
SMIMEEnvelopedGenerator.AES256_CBC, "BC");
// MimeBodyPart mp = gen.generate(msg,
SMIMEEnvelopedGenerator.AES192_CBC, "BC");
MimeBodyPart mp = gen.generate(msg,
SMIMEEnvelopedGenerator.AES128_CBC, "BC");



// Get a Session object and create the mail message
//
Properties props = System.getProperties();
Session session = Session.getDefaultInstance(props, null);

Address fromUser = new InternetAddress("\"Eric H.
Echidna\"<eric@bouncycastle.org>");
Address toUser = new
InternetAddress("example@bouncycastle.org");

MimeMessage body = new MimeMessage(session);
body.setFrom(fromUser);
body.setRecipient(Message.RecipientType.TO, toUser);
body.setSubject("example encrypted message");
body.setContent(mp.getContent(), mp.getContentType());
body.saveChanges();

body.writeTo(new FileOutputStream("encrypted.message"));
}
}