AES加密解密long型id

小灰灰 2022-11-29 05:34 45阅读 0赞

Java实现的一个生成系统内唯一且无法被伪造的订单号的工具，基本思路是对long型自增的id加密解密，加密算法是AES，需要结合其他encode/  
decode方法。

## AESUtil ##

加密解密的工具类

import javax.crypto.BadPaddingException;
    import javax.crypto.Cipher;
    import javax.crypto.IllegalBlockSizeException;
    import javax.crypto.NoSuchPaddingException;
    import javax.crypto.spec.SecretKeySpec;
    import java.nio.charset.StandardCharsets;
    import java.security.InvalidKeyException;
    import java.security.NoSuchAlgorithmException;
    
    public class AESUtil { 
        private static final byte[] SECRET_KEY = "7975922666f6eb02".getBytes(StandardCharsets.UTF_8);
    
        public static byte[] encrypt(byte[] plaintext) throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException { 
            SecretKeySpec secretKeySpec = new SecretKeySpec(SECRET_KEY, "AES");
            // 算法/模式/补码方式
            Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
            cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec);
            return cipher.doFinal(plaintext);
        }
    
        public static byte[] decrypt(byte[] ciphertext) throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException { 
                SecretKeySpec secretKeySpec = new SecretKeySpec(SECRET_KEY, "AES");
                Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
                cipher.init(Cipher.DECRYPT_MODE, secretKeySpec);
                return cipher.doFinal(ciphertext);
        }
    
        public static byte[] encryptId(long id) throws IllegalBlockSizeException, InvalidKeyException, BadPaddingException, NoSuchAlgorithmException, NoSuchPaddingException { 
            byte[] plaintext = new byte[8];
            for(int i = 0;i < 8; ++i) { 
                plaintext[i] = (byte) ((id >> (7 - i) * 8) & 0xFF);
            }
            return encrypt(plaintext);
        }
    
        public static long decryptId(byte[] ciphertext) throws IllegalBlockSizeException, InvalidKeyException, BadPaddingException, NoSuchAlgorithmException, NoSuchPaddingException { 
            long id = 0;
            byte[] plaintext = decrypt(ciphertext);
            for(int i = 0;i < 8; ++i) { 
                id |= (long) (plaintext[i] & 0xFF) << (7 -i) * 8;
            }
            return id;
        }
    }

加密后得到的是byte数组，需要结合encode工具，下面是一个Base58编码工具

## Base58Util ##

import java.math.BigInteger;
    
    public class Base58Util { 
        private static final String ALPHABET = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
        private static final BigInteger BASE = BigInteger.valueOf(58L);
    
        public Base58Util() { 
        }
    
        public static String encode(byte[] input) { 
            BigInteger bi = new BigInteger(1, input);
    
            StringBuffer s;
            BigInteger mod;
            for(s = new StringBuffer(); bi.compareTo(BASE) >= 0; bi = bi.subtract(mod).divide(BASE)) { 
                mod = bi.mod(BASE);
                s.insert(0, "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz".charAt(mod.intValue()));
            }
    
            s.insert(0, "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz".charAt(bi.intValue()));
            byte[] var7 = input;
            int var4 = input.length;
    
            for(int var5 = 0; var5 < var4; ++var5) { 
                byte anInput = var7[var5];
                if (anInput != 0) { 
                    break;
                }
    
                s.insert(0, "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz".charAt(0));
            }
    
            return s.toString();
        }
    
        public static byte[] decode(String input) { 
            byte[] bytes = decodeToBigInteger(input).toByteArray();
            boolean stripSignByte = bytes.length > 1 && bytes[0] == 0 && bytes[1] < 0;
            int leadingZeros = 0;
    
            for(int i = 0; input.charAt(i) == "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz".charAt(0); ++i) { 
                ++leadingZeros;
            }
    
            byte[] tmp = new byte[bytes.length - (stripSignByte ? 1 : 0) + leadingZeros];
            System.arraycopy(bytes, stripSignByte ? 1 : 0, tmp, leadingZeros, tmp.length - leadingZeros);
            return tmp;
        }
    
        public static BigInteger decodeToBigInteger(String input) { 
            BigInteger bi = BigInteger.valueOf(0L);
    
            for(int i = input.length() - 1; i >= 0; --i) { 
                int alphaIndex = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz".indexOf(input.charAt(i));
                if (alphaIndex == -1) { 
                    throw new IllegalStateException("Illegal character " + input.charAt(i) + " at " + i);
                }
    
                bi = bi.add(BigInteger.valueOf((long)alphaIndex).multiply(BASE.pow(input.length() - 1 - i)));
            }
    
            return bi;
        }
    }