对称加密算法Blowfish(java).rar

/* * To change this template, choose Tools | Templates * and open the template in the editor. */ package blowfish; import java.io.UnsupportedEncodingException; import java.security.InvalidKeyException; import java.security.NoSuchAlgorithmException; import javax.crypto.BadPaddingException; import javax.crypto.Cipher; import javax.crypto.IllegalBlockSizeException; import javax.crypto.NoSuchPaddingException; import javax.crypto.spec.SecretKeySpec; /** 2. * BlowFish的加密和復元的样本 3. */ public class BlowFish { public static final String ENCODING = "UTF-8"; // 32bit - 128bit (448bit) public static final String TEST_KEY = "＊＊＊＊＊＊＊＊＊"; /** 12. * 把byte数组变换为16進数的字符串。 13. * 14. * @param bytes 15. * byte数组 16. * @return 16進数的字符串 17. */ public static String byteToString(byte[] bytes) { StringBuffer buf = new StringBuffer(); for (int i = 0; i < bytes.length; i++) { int d = bytes[i]; if (d < 0) { d += 256; } if (d < 16) { buf.append("0"); } buf.append(Integer.toString(d, 16)); } return buf.toString(); } /** 37. * 把16進数的字符串变换为byte数组。 38. * 39. * @param string 40. * 16進数的字符串 41. * @return byte数组 42. */ public static byte[] stringToByte(String string) { byte[] bytes = new byte[string.length() / 2]; String b; for (int i = 0; i < string.length() / 2; i++) { b = string.substring(i * 2, i * 2 + 2); bytes[i] = (byte) Integer.parseInt(b, 16); } return bytes; } /** 57. * 返回把字符串用暗号键加密的byte数组。 58. * 59. * @param key 60. * 暗号键 61. * @param text 62. * 加密的字符串 63. * @return 把字符串加密的byte数组 64. * @throws NoSuchAlgorithmException 65. * @throws NoSuchPaddingException 66. * @throws InvalidKeyException 67. * @throws IllegalBlockSizeException 68. * @throws BadPaddingException 69. * @throws UnsupportedEncodingException 70. */ public static byte[] encrypt(String key, String text) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException { SecretKeySpec sksSpec = new SecretKeySpec(key.getBytes(), "Blowfish"); // BlowFish的加密mode是ECB、Padding方式是PKCS5Padding。 Cipher cipher = Cipher.getInstance("Blowfish/ECB/PKCS5Padding"); cipher.init(Cipher.ENCRYPT_MODE, sksSpec); byte[] encrypted = cipher.doFinal(text.getBytes(ENCODING)); return encrypted; } /** 84. * 返回加密的byte数组用暗号键復元的字符串。 85. * 86. * @param key 87. * 暗号键 88. * @param encrypted 89. * 加密的byte数组 90. * @return 91. * @throws NoSuchAlgorithmException 92. * @throws NoSuchPaddingException 93. * @throws InvalidKeyException 94. * @throws IllegalBlockSizeException 95. * @throws BadPaddingException 96. * @throws UnsupportedEncodingException 97. */ public static String decrypt(String key, byte[] encrypted) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException { SecretKeySpec sksSpec = new SecretKeySpec(key.getBytes(), "Blowfish"); // BlowFish的加密mode是ECB、Padding方式是PKCS5Padding。 Cipher cipher = Cipher.getInstance("Blowfish/ECB/PKCS5Padding"); cipher.init(Cipher.DECRYPT_MODE, sksSpec); byte[] decrypted = cipher.doFinal(encrypted); return new String(decrypted, ENCODING); } /** 111. * 从命令行开始的使用方法 112. */ private static void usage() { System.out.println("Usage: java BlowFish <encode|decode> [key] <text>"); System.exit(-1); } /** 120. * <pre> 121. * 122. * Test 123. * <pre> 124. */ public static void main(String[] args) { String key; String text; if (args.length < 2) { usage(); } if (args.length == 2) { key = TEST_KEY; text = args[1]; } else { key = args[1]; text = args[2]; } String type = args[0].toLowerCase(); try { if (type.equals("encode")) { System.out.println("Key = " + key); System.out.println("Text = " + text); System.out.println("Encrypted = " + byteToString(encrypt(key, text))); } else if (type.equals("decode")) { System.out.println("Key = " + key); System.out.println("Text = " + text); System.out.println("Decrypted = " + decrypt(key, stringToByte(text))); } else { usage(); } } catch (Exception e) { e.printStackTrace(); } } }