为什么80%的码农都做不了架构师？>>>
需求： 实现RSA非对称加密算法 实现： public static class RSACoder { public static final String KEY_ALGORITHM = "RSA"; private static final int KEY_SIZE = 512; private static final String PUBLIC_KEY = "RSAPublicKey"; private static final String PRIVATE_KEY = "RSAPrivateKey";
public static Map<String, Object> initKey() throws Exception {KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(KEY_ALGORITHM);keyPairGenerator.initialize(KEY_SIZE);KeyPair keyPair = keyPairGenerator.generateKeyPair();RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();Map<String, Object> keyMap = new HashMap<String, Object>();keyMap.put(PUBLIC_KEY, publicKey);keyMap.put(PRIVATE_KEY, privateKey);return keyMap;}public static byte[] encryptByPrivateKey(byte[] data, byte[] key)throws Exception {PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(key);KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);PrivateKey privateKey = keyFactory.generatePrivate(pkcs8KeySpec);Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.ENCRYPT_MODE, privateKey);return cipher.doFinal(data);}public static byte[] encryptByPublicKey(byte[] data, byte[] key)throws Exception {KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(key);PublicKey pubKey = keyFactory.generatePublic(x509KeySpec);Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.ENCRYPT_MODE, pubKey);return cipher.doFinal(data);}public static byte[] decryptByPrivateKey(byte[] data, byte[] key)throws Exception {PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(key);KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);PrivateKey privateKey = keyFactory.generatePrivate(pkcs8KeySpec);Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.DECRYPT_MODE, privateKey);return cipher.doFinal(data);}public static byte[] decryptByPublicKey(byte[] data, byte[] key)throws Exception {KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(key);PublicKey pubKey = keyFactory.generatePublic(x509KeySpec);Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.DECRYPT_MODE, pubKey);return cipher.doFinal(data);}public static byte[] getPrivateKey(Map<String, Object> keyMap) {Key key = (Key) keyMap.get(PRIVATE_KEY);return key.getEncoded();}public static byte[] getPublicKey(Map<String, Object> keyMap)throws Exception {Key key = (Key) keyMap.get(PUBLIC_KEY);return key.getEncoded();}
}
