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Simple Symmetric Encryption in Java problem

I have a simple symmetric encryption taken from the book "Beginning Cryptography with Java
by David Hook".

I have a problem that I cannot run the original code as expected.

In the very original code below:
I got the runtime error as:
Exception in thread "main" java.security.NoSuchProviderException: No such provider: BC
      at javax.crypto.Cipher.getInstance(Unknown Source)
      at SimpleSymmetricExample.main(SimpleSymmetricExample.java:23)

If I convert the line from:
Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding", "BC");
to:
Cipher cipher = Cipher.getInstance("AES");

I got the output as:
input text : 00112233445566778899aabbccddeeff
Exception in thread "main" java.security.InvalidKeyException: Illegal key size or default parameters
      at javax.crypto.Cipher.a(Unknown Source)
      at javax.crypto.Cipher.a(Unknown Source)
      at javax.crypto.Cipher.a(Unknown Source)
      at javax.crypto.Cipher.init(Unknown Source)
      at javax.crypto.Cipher.init(Unknown Source)
      at SimpleSymmetricExample.main(SimpleSymmetricExample.java:31)
line 31 is as follows:
cipher.init(Cipher.ENCRYPT_MODE, key);

Note that I have NOT used any library in the first place.
I also tried to use the jar files in the link: http://www.bouncycastle.org/download/crypto-144.zip

What should I do to fix it?

Best regards.

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

/**
 * Basic symmetric encryption example
 */
////Utils
class Utils
{
    private static String digits = "0123456789abcdef";

    /**
     * Return length many bytes of the passed in byte array as a hex string.
     *
     * @param data the bytes to be converted.
     * @param length the number of bytes in the data block to be converted.
     * @return a hex representation of length bytes of data.
     */
    public static String toHex(byte[] data, int length)
    {
        StringBuffer    buf = new StringBuffer();

        for (int i = 0; i != length; i++)
        {
            int v = data[i] & 0xff;

            buf.append(digits.charAt(v >> 4));
            buf.append(digits.charAt(v & 0xf));
        }

        return buf.toString();
    }

    /**
     * Return the passed in byte array as a hex string.
     *
     * @param data the bytes to be converted.
     * @return a hex representation of data.
     */
    public static String toHex(byte[] data)
    {
        return toHex(data, data.length);
    }
}

//////SimpleSymmetricExample
public class SimpleSymmetricExample
{
    public static void main(String[] args) throws Exception
    {
        byte[]        input = new byte[] {
                          0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
                          (byte)0x88, (byte)0x99, (byte)0xaa, (byte)0xbb,
                          (byte)0xcc, (byte)0xdd, (byte)0xee, (byte)0xff };
        byte[]        keyBytes = new byte[] {
                          0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
                          0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
                          0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17 };

        SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");

        Cipher        cipher = Cipher.getInstance("AES/ECB/NoPadding", "BC");

        System.out.println("input text : " + Utils.toHex(input));

        // encryption pass

        byte[] cipherText = new byte[input.length];

        cipher.init(Cipher.ENCRYPT_MODE, key);

        int ctLength = cipher.update(input, 0, input.length, cipherText, 0);

        ctLength += cipher.doFinal(cipherText, ctLength);

        System.out.println("cipher text: " + Utils.toHex(cipherText)
                                                     + " bytes: " + ctLength);

        // decryption pass

        byte[] plainText = new byte[ctLength];

        cipher.init(Cipher.DECRYPT_MODE, key);

        int ptLength = cipher.update(cipherText, 0, ctLength, plainText, 0);

        ptLength += cipher.doFinal(plainText, ptLength);

        System.out.println("plain text : " + Utils.toHex(plainText)
                                                     + " bytes: " + ptLength);
    }
}

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Gurvinder Pal Singh

can you replace line number 62 by
Cipher c1 = Cipher.getInstance("DES");

for reference see
http://java.sun.com/j2se/1.4.2/docs/guide/security/jce/JCERefGuide.html#SimpleEncrEx

ASKER CERTIFIED SOLUTION

Gurvinder Pal Singh

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jazzIIIlove

ASKER

As in the code snippet, I added Cipher cipher = Cipher.getInstance("DES"); and Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
but the result is as follows:

What am I doing wrong?

input text : 00112233445566778899aabbccddeeff
Exception in thread "main" java.security.InvalidKeyException
      at com.ibm.crypto.provider.DESCipher.engineGetKeySize(Unknown Source)
      at javax.crypto.Cipher.b(Unknown Source)
      at javax.crypto.Cipher.a(Unknown Source)
      at javax.crypto.Cipher.a(Unknown Source)
      at javax.crypto.Cipher.a(Unknown Source)
      at javax.crypto.Cipher.init(Unknown Source)
      at javax.crypto.Cipher.init(Unknown Source)
      at SimpleSymmetricExample.main(SimpleSymmetricExample.java:74)

import java.security.Security;

import javax.crypto.Cipher; 
import javax.crypto.spec.SecretKeySpec; 
 
/** 
 * Basic symmetric encryption example 
 */ 
////Utils 
class Utils 
{ 
    private static String digits = "0123456789abcdef"; 
 
    /** 
     * Return length many bytes of the passed in byte array as a hex string. 
     * 
     * @param data the bytes to be converted. 
     * @param length the number of bytes in the data block to be converted. 
     * @return a hex representation of length bytes of data. 
     */ 
    public static String toHex(byte[] data, int length) 
    { 
        StringBuffer    buf = new StringBuffer(); 
 
        for (int i = 0; i != length; i++) 
        { 
            int v = data[i] & 0xff; 
 
            buf.append(digits.charAt(v >> 4)); 
            buf.append(digits.charAt(v & 0xf)); 
        } 
 
        return buf.toString(); 
    } 
 
    /** 
     * Return the passed in byte array as a hex string. 
     * 
     * @param data the bytes to be converted. 
     * @return a hex representation of data. 
     */ 
    public static String toHex(byte[] data) 
    { 
        return toHex(data, data.length); 
    } 
} 
 
//////SimpleSymmetricExample 
public class SimpleSymmetricExample 
{ 
    public static void main(String[] args) throws Exception 
    { 
    	Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
        byte[]        input = new byte[] { 
                          0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 
                          (byte)0x88, (byte)0x99, (byte)0xaa, (byte)0xbb, 
                          (byte)0xcc, (byte)0xdd, (byte)0xee, (byte)0xff }; 
        byte[]        keyBytes = new byte[] { 
                          0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 
                          0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 
                          0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17 }; 
 
        SecretKeySpec key = new SecretKeySpec(keyBytes, "AES"); 
 
        //Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding", "BC");
        Cipher cipher = Cipher.getInstance("DES");
 
        System.out.println("input text : " + Utils.toHex(input)); 
 
        // encryption pass 
 
        byte[] cipherText = new byte[input.length]; 
 
        cipher.init(Cipher.ENCRYPT_MODE, key); 
 
        int ctLength = cipher.update(input, 0, input.length, cipherText, 0); 
 
        ctLength += cipher.doFinal(cipherText, ctLength); 
 
        System.out.println("cipher text: " + Utils.toHex(cipherText) 
                                                     + " bytes: " + ctLength); 
 
        // decryption pass 
 
        byte[] plainText = new byte[ctLength]; 
 
        cipher.init(Cipher.DECRYPT_MODE, key); 
 
        int ptLength = cipher.update(cipherText, 0, ctLength, plainText, 0); 
 
        ptLength += cipher.doFinal(plainText, ptLength); 
 
        System.out.println("plain text : " + Utils.toHex(plainText) 
                                                     + " bytes: " + ptLength); 
    } 
}

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jazzIIIlove

ASKER

the problem is in the line: cipher.init(Cipher.ENCRYPT_MODE, key);

SOLUTION

Gurvinder Pal Singh

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