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POHow do I use 3DES encryption/decryption in Java?
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copied!<p>Every method I write to encode a string in Java using 3DES can't be decrypted back to the original string. Does anyone have a simple code snippet that can just encode and then decode the string back to the original string?</p> <p>I know I'm making a very silly mistake somewhere in this code. Here's what I've been working with so far:</p> <p>** note, I am not returning the BASE64 text from the encrypt method, and I am not base64 un-encoding in the decrypt method because I was trying to see if I was making a mistake in the BASE64 part of the puzzle.</p> <pre><code>public class TripleDESTest { public static void main(String[] args) { String text = "kyle boon"; byte[] codedtext = new TripleDESTest().encrypt(text); String decodedtext = new TripleDESTest().decrypt(codedtext); System.out.println(codedtext); System.out.println(decodedtext); } public byte[] encrypt(String message) { try { final MessageDigest md = MessageDigest.getInstance("md5"); final byte[] digestOfPassword = md.digest("HG58YZ3CR9".getBytes("utf-8")); final byte[] keyBytes = Arrays.copyOf(digestOfPassword, 24); for (int j = 0, k = 16; j < 8;) { keyBytes[k++] = keyBytes[j++]; } final SecretKey key = new SecretKeySpec(keyBytes, "DESede"); final IvParameterSpec iv = new IvParameterSpec(new byte[8]); final Cipher cipher = Cipher.getInstance("DESede/CBC/PKCS5Padding"); cipher.init(Cipher.ENCRYPT_MODE, key, iv); final byte[] plainTextBytes = message.getBytes("utf-8"); final byte[] cipherText = cipher.doFinal(plainTextBytes); final String encodedCipherText = new sun.misc.BASE64Encoder().encode(cipherText); return cipherText; } catch (java.security.InvalidAlgorithmParameterException e) { System.out.println("Invalid Algorithm"); } catch (javax.crypto.NoSuchPaddingException e) { System.out.println("No Such Padding"); } catch (java.security.NoSuchAlgorithmException e) { System.out.println("No Such Algorithm"); } catch (java.security.InvalidKeyException e) { System.out.println("Invalid Key"); } catch (BadPaddingException e) { System.out.println("Invalid Key");} catch (IllegalBlockSizeException e) { System.out.println("Invalid Key");} catch (UnsupportedEncodingException e) { System.out.println("Invalid Key");} return null; } public String decrypt(byte[] message) { try { final MessageDigest md = MessageDigest.getInstance("md5"); final byte[] digestOfPassword = md.digest("HG58YZ3CR9".getBytes("utf-8")); final byte[] keyBytes = Arrays.copyOf(digestOfPassword, 24); for (int j = 0, k = 16; j < 8;) { keyBytes[k++] = keyBytes[j++]; } final SecretKey key = new SecretKeySpec(keyBytes, "DESede"); final IvParameterSpec iv = new IvParameterSpec(new byte[8]); final Cipher decipher = Cipher.getInstance("DESede/CBC/PKCS5Padding"); decipher.init(Cipher.DECRYPT_MODE, key, iv); //final byte[] encData = new sun.misc.BASE64Decoder().decodeBuffer(message); final byte[] plainText = decipher.doFinal(message); return plainText.toString(); } catch (java.security.InvalidAlgorithmParameterException e) { System.out.println("Invalid Algorithm"); } catch (javax.crypto.NoSuchPaddingException e) { System.out.println("No Such Padding"); } catch (java.security.NoSuchAlgorithmException e) { System.out.println("No Such Algorithm"); } catch (java.security.InvalidKeyException e) { System.out.println("Invalid Key"); } catch (BadPaddingException e) { System.out.println("Invalid Key");} catch (IllegalBlockSizeException e) { System.out.println("Invalid Key");} catch (UnsupportedEncodingException e) { System.out.println("Invalid Key");} catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } } </code></pre>

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