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| Rev | Author | Line No. | Line |
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| 156 | jmachado | 1 | package jomm.utils; |
| 2 | |||
| 3 | import javax.crypto.Cipher; |
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| 4 | import javax.crypto.SecretKey; |
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| 5 | import javax.crypto.IllegalBlockSizeException; |
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| 6 | import javax.crypto.KeyGenerator; |
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| 7 | import javax.crypto.spec.SecretKeySpec; |
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| 8 | import java.io.UnsupportedEncodingException; |
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| 9 | import java.security.NoSuchAlgorithmException; |
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| 10 | |||
| 11 | /** |
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| 12 | * @author Jorge Machado |
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| 13 | * @date 20/Mai/2008 |
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| 14 | * @see jomm.utils |
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| 15 | */ |
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| 16 | public class DesUtils |
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| 17 | { |
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| 18 | static 1.5.0/docs/api/javax/crypto/Cipher.html">Cipher ecipher; |
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| 19 | static 1.5.0/docs/api/javax/crypto/Cipher.html">Cipher dcipher; |
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| 20 | |||
| 21 | static 1.5.0/docs/api/javax/crypto/SecretKey.html">SecretKey key; |
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| 22 | |||
| 23 | |||
| 24 | public static byte[] addParity(byte[] in) { |
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| 25 | byte[] result = new byte[8]; |
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| 26 | |||
| 27 | // Keeps track of the bit position in the result |
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| 28 | int resultIx = 1; |
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| 29 | |||
| 30 | // Used to keep track of the number of 1 bits in each 7-bit chunk |
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| 31 | int bitCount = 0; |
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| 32 | |||
| 33 | // Process each of the 56 bits |
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| 34 | for (int i=0; i<56; i++) { |
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| 35 | // Get the bit at bit position i |
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| 36 | boolean bit = (in[6-i/8]&(1<<(i%8))) > 0; |
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| 37 | |||
| 38 | // If set, set the corresponding bit in the result |
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| 39 | if (bit) { |
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| 40 | result[7-resultIx/8] |= (1<<(resultIx%8))&0xFF; |
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| 41 | bitCount++; |
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| 42 | } |
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| 43 | |||
| 44 | // Set the parity bit after every 7 bits |
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| 45 | if ((i+1) % 7 == 0) { |
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| 46 | if (bitCount % 2 == 0) { |
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| 47 | // Set low-order bit (parity bit) if bit count is even |
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| 48 | result[7-resultIx/8] |= 1; |
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| 49 | } |
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| 50 | resultIx++; |
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| 51 | bitCount = 0; |
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| 52 | } |
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| 53 | resultIx++; |
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| 54 | } |
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| 55 | return result; |
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| 56 | } |
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| 57 | |||
| 58 | // Get the 56-bit value |
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| 59 | |||
| 60 | |||
| 61 | private static DesUtils desUtils; |
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| 62 | |||
| 63 | private DesUtils() |
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| 64 | { |
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| 65 | try { |
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| 66 | byte[] raw = new byte[]{0x01, 0x72, 0x43, 0x3E, 0x1C, 0x7A, 0x55}; |
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| 67 | byte[] keyBytes = addParity(raw); |
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| 68 | key = new 1.5.0/docs/api/javax/crypto/spec/SecretKeySpec.html">SecretKeySpec(keyBytes, "DES"); |
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| 69 | ecipher = 1.5.0/docs/api/javax/crypto/Cipher.html">Cipher.getInstance("DES"); |
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| 70 | dcipher = 1.5.0/docs/api/javax/crypto/Cipher.html">Cipher.getInstance("DES"); |
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| 71 | ecipher.init(1.5.0/docs/api/javax/crypto/Cipher.html">Cipher.ENCRYPT_MODE, key); |
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| 72 | dcipher.init(1.5.0/docs/api/javax/crypto/Cipher.html">Cipher.DECRYPT_MODE, key); |
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| 73 | |||
| 74 | } catch (javax.crypto.1.5.0/docs/api/javax/crypto/NoSuchPaddingException.html">NoSuchPaddingException e) { |
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| 75 | e.printStackTrace(); |
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| 76 | } catch (java.security.1.5.0/docs/api/java/security/NoSuchAlgorithmException.html">NoSuchAlgorithmException e) { |
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| 77 | e.printStackTrace(); |
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| 78 | } catch (java.security.5+0%2Fdocs%2Fapi+InvalidKeyException">InvalidKeyException e) { |
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| 79 | e.printStackTrace(); |
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| 80 | } |
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| 81 | } |
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| 82 | |||
| 83 | public static DesUtils getInstance() |
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| 84 | { |
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| 85 | if(desUtils == null) |
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| 86 | desUtils = new DesUtils(); |
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| 87 | return desUtils; |
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| 88 | } |
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| 89 | |||
| 90 | public 1.5.0/docs/api/java/lang/String.html">String encrypt(1.5.0/docs/api/java/lang/String.html">String str) { |
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| 91 | try { |
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| 92 | // Encode the string into bytes using utf-8 |
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| 93 | byte[] utf8 = str.getBytes("UTF8"); |
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| 94 | |||
| 95 | // Encrypt |
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| 96 | byte[] enc = ecipher.doFinal(utf8); |
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| 97 | |||
| 98 | // Encode bytes to base64 to get a string |
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| 99 | return new sun.misc.BASE64Encoder().encode(enc); |
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| 100 | } catch (javax.crypto.1.5.0/docs/api/javax/crypto/BadPaddingException.html">BadPaddingException e) { |
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| 101 | } catch (1.5.0/docs/api/javax/crypto/IllegalBlockSizeException.html">IllegalBlockSizeException e) { |
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| 102 | } catch (1.5.0/docs/api/java/io/UnsupportedEncodingException.html">UnsupportedEncodingException e) { |
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| 103 | } catch (java.io.1.5.0/docs/api/java/io/IOException.html">IOException e) { |
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| 104 | } |
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| 105 | return null; |
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| 106 | } |
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| 107 | |||
| 108 | public 1.5.0/docs/api/java/lang/String.html">String decrypt(1.5.0/docs/api/java/lang/String.html">String str) { |
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| 109 | try { |
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| 110 | // Decode base64 to get bytes |
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| 111 | byte[] dec = new sun.misc.BASE64Decoder().decodeBuffer(str); |
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| 112 | |||
| 113 | // Decrypt |
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| 114 | byte[] utf8 = dcipher.doFinal(dec); |
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| 115 | |||
| 116 | // Decode using utf-8 |
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| 117 | return new 1.5.0/docs/api/java/lang/String.html">String(utf8, "UTF8"); |
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| 118 | } catch (javax.crypto.1.5.0/docs/api/javax/crypto/BadPaddingException.html">BadPaddingException e) { |
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| 119 | } catch (1.5.0/docs/api/javax/crypto/IllegalBlockSizeException.html">IllegalBlockSizeException e) { |
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| 120 | } catch (1.5.0/docs/api/java/io/UnsupportedEncodingException.html">UnsupportedEncodingException e) { |
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| 121 | } catch (java.io.1.5.0/docs/api/java/io/IOException.html">IOException e) { |
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| 122 | } |
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| 123 | return null; |
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| 124 | } |
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| 125 | |||
| 126 | public static void main(1.5.0/docs/api/java/lang/String.html">String[] args) |
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| 127 | { |
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| 128 | 1.5.0/docs/api/java/lang/String.html">String code = DesUtils.getInstance().encrypt("jorge machado"); |
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| 129 | 1.5.0/docs/api/java/lang/System.html">System.out.println(code); |
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| 130 | 1.5.0/docs/api/java/lang/System.html">System.out.println(DesUtils.getInstance().decrypt(code)); |
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| 131 | } |
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| 132 | } |