RSA cipher creation

Question

hi, i encounter a problem when i try to generate RSA cipher, here is the code:
// generate RSA cipher
try {
cp = Cipher.getInstance("RSA");
} catch (NoSuchAlgorithmException ex) {
System.out.println("RSA cipher not found in provider.");
return;
And the error is "RSA cipher not found in provider". My current compiler version used is j2sdk1.4.2_02.
can anyone help me to solve this, thx a lot.

Answer 1

hi ggainey,
thx for ur help, i've downloaded the bouncycastle .jar file.
Everything seem alright, but i encountered an error when i execute my program.
Error :
Exception in thread "main" java.lang.SecurityException: The provider BC may not be signed by a trusted party
at javax.crypto.SunJCE_b.a(DashoA6275)
at javax.crypto.Cipher.a(DashoA6275)
at javax.crypto.Cipher.getInstance(DashoA6275)
at SampleRSACrypto.main(SampleRSACrypto.java:64)
here is my program code :
import java.io.*;
import java.util.Arrays;
import java.security.Security;
import java.security.Provider;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import javax.crypto.Cipher;
import javax.crypto.NoSuchPaddingException;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
public class SampleRSACrypto {
static final byte[] plainText = "Secret Message".getBytes();
public static void main(String argv[]) {
KeyPairGenerator rsaKeyPairGen;
KeyPair rsaKeyPair;
PublicKey rsaPub;
PrivateKey rsaPriv;
Cipher cp = null;
byte[] cipherText = null, newPlainText = null;
// Add a RSA security provider
try {
          Security.addProvider(new BouncyCastleProvider());
     catch(Exception e) {
          System.err.println("Error loading security provider (" + e.getMessage() + ")");
// Generate an RSA key pair
try {
rsaKeyPairGen = KeyPairGenerator.getInstance("RSA", "BC");
} catch (NoSuchAlgorithmException ex) {
System.out.println("RSA KeyPair Generator not found in bouncycastle provider.");
return;
} catch (NoSuchProviderException ex) {
// Should not happen.
System.out.println("Provider bouncycastle not found.");
return;
// Use modulus length = 1024
rsaKeyPairGen.initialize(1024);
rsaKeyPair = rsaKeyPairGen.generateKeyPair();
if (rsaKeyPair == null) {
System.out.println("Key generation failure. KeyPair was not generated.");
return;
// get RSA public key.
rsaPub = rsaKeyPair.getPublic();
// get RSA private key.
rsaPriv = rsaKeyPair.getPrivate();
// generate RSA cipher
try {
cp = Cipher.getInstance("RSA", "BC");
} catch (NoSuchAlgorithmException ex) {
System.out.println("RSA cipher not found in bouncycastle provider.");
return;
} catch (NoSuchProviderException ex) {
// Should not happen.
System.out.println("Provider bouncycastle not found.");
return;
} catch (NoSuchPaddingException ex) {
// Should not happen.
System.out.println("Invalid padding.");
return;
// Encrypt the plain text
try {
cp.init(Cipher.ENCRYPT_MODE, rsaPub);
cipherText = cp.doFinal(plainText);
} catch (Exception ex) {
System.out.println("Error encrypting: " + ex.getMessage());
return;
// Decrypt the cipher text
try {
cp.init(Cipher.DECRYPT_MODE, rsaPriv);
newPlainText = cp.doFinal(cipherText);
} catch (Exception ex) {
System.out.println("Error decrypting: " + ex.getMessage());
return;
// Verify the result.
if (Arrays.equals(plainText, newPlainText)) {
System.out.println("Encryption and decryption successful.");
} else {
System.out.println("Encryption and decryption not successful.");
i downloaded the .jar file from http://www.bouncycastle.org/latest_releases.html, do u have any idea of why i got such an error in my program?
thx a lot.