byte hex convert

Author: Kuangcp

class/src/main/java/com/github/kuangcp/util/ShowBinary.java

@@ -1,23 +1,55 @@
 package com.github.kuangcp.util;
 
+import java.math.BigInteger;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
 /**
  * @author kuangcp on 3/14/19-2:26 PM
  */
 public class ShowBinary {
 
-  public static String toBinary(Byte value) {
-    return Integer.toBinaryString(value);
-  }
+    public static String toBinary(Byte value) {
+        return Integer.toBinaryString(value);
+    }
+
+    public static String toBinary(Integer value) {
+        return Integer.toBinaryString(value);
+    }
+
+    public static String toBinary(Double value) {
+        return Long.toBinaryString(Double.doubleToRawLongBits(value));
+    }
+
+    public static String toBinary(Float value) {
+        return Float.toHexString(value);
+    }
 
-  public static String toBinary(Integer value) {
-    return Integer.toBinaryString(value);
-  }
+    /**
+     * https://stackoverflow.com/questions/9655181/java-convert-a-byte-array-to-a-hex-string
+     * 风险：当转整数后前缀出现0，会丢失字节
+     */
+    public static String byteToHex2(byte[] value) {
+        return new BigInteger(1, value).toString(16);
+    }
 
-  public static String toBinary(Double value) {
-    return Long.toBinaryString(Double.doubleToRawLongBits(value));
-  }
+    public static String byteToHex(byte[] value) {
+        return IntStream.range(0, value.length)
+                .mapToObj(i -> String.format("%02X", value[i]))
+                .collect(Collectors.joining());
+    }
 
-  public static String toBinary(Float value) {
-    return Float.toHexString(value);
-  }
+    public static byte[] hexToByte(String hex) {
+        byte[] ans = new byte[hex.length() / 2];
+        for (int i = 0; i < ans.length; i++) {
+            int index = i * 2;
+            int val = Integer.parseInt(hex.substring(index, index + 2), 16);
+            ans[i] = (byte) val;
+        }
+//        for (byte b : ans) {
+//            System.out.print(b + " ");
+//        }
+//        System.out.println(hex.length() + " " + ans.length);
+        return ans;
+    }
 }

class/src/main/java/security/aes/AESUtil.java

@@ -1,5 +1,7 @@
 package security.aes;
 
+import com.github.kuangcp.util.ShowBinary;
+
 import javax.crypto.*;
 import javax.crypto.spec.IvParameterSpec;
 import javax.crypto.spec.PBEKeySpec;
@@ -20,6 +22,43 @@
 
 public class AESUtil {
 
+
+    public static byte[] encrypt(String hexKey, byte[] data) throws Exception {
+        return encrypt(ShowBinary.hexToByte(hexKey), data);
+    }
+
+    public static byte[] decrypt(String hexKey, byte[] data) throws Exception {
+        return decrypt(ShowBinary.hexToByte(hexKey), data);
+    }
+
+    /**
+     * 加密
+     *
+     * @param key  密钥
+     * @param data 加密数据
+     * @return 密文
+     */
+    public static byte[] encrypt(byte[] key, byte[] data) throws Exception {
+        SecretKeySpec secretKeySpec = new SecretKeySpec(key, "AES");
+        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
+        cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec);
+        return cipher.doFinal(data);
+    }
+
+    /**
+     * 解密
+     *
+     * @param key  密钥
+     * @param data 密文
+     * @return 解密后的数据
+     */
+    public static byte[] decrypt(byte[] key, byte[] data) throws Exception {
+        SecretKeySpec secretKeySpec = new SecretKeySpec(key, "AES");
+        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
+        cipher.init(Cipher.DECRYPT_MODE, secretKeySpec);
+        return cipher.doFinal(data);
+    }
+
     public static String encrypt(String algorithm, String input, SecretKey key, IvParameterSpec iv)
             throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException,
             InvalidKeyException, BadPaddingException, IllegalBlockSizeException {

class/src/test/java/security/aes/AESUtilTest.java

@@ -1,10 +1,12 @@
 package security.aes;
 
 
+import com.github.kuangcp.util.ShowBinary;
 import lombok.extern.slf4j.Slf4j;
 import org.junit.Assert;
 import org.junit.Test;
 
+import javax.crypto.KeyGenerator;
 import javax.crypto.SealedObject;
 import javax.crypto.SecretKey;
 import javax.crypto.spec.IvParameterSpec;
@@ -14,13 +16,66 @@
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.security.SecureRandom;
+import java.util.Base64;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 
 @Slf4j
 public class AESUtilTest {
 
 
+    @Test
+    public void testFlow() throws Exception {
+        // 生成随机密钥
+        KeyGenerator keyGenerator = KeyGenerator.getInstance("AES");
+        // 128 192 256
+        keyGenerator.init(128, new SecureRandom());
+        SecretKey secretKey = keyGenerator.generateKey();
+
+        byte[] key = secretKey.getEncoded();
+        System.out.println("AES 密钥：" + Base64.getEncoder().encodeToString(key));
+        System.out.println("AES 密钥：" + ShowBinary.byteToHex(key));
+
+        String content = "KeyGenerator keyGenerator = KeyGenerator.getInstance(\"AES\");";
+        System.out.println("原文：" + content);
+
+        byte[] ret = AESUtil.encrypt(key, content.getBytes());
+        System.out.println("密文：" + Base64.getEncoder().encodeToString(ret));
+        System.out.println("密文：" + ShowBinary.byteToHex(ret));
+
+        byte[] raw = AESUtil.decrypt(key, ret);
+        System.out.println("原文：" + new String(raw));
+        Assert.assertEquals(content, new String(raw));
+    }
+
+    @Test
+    public void testHexKeyFlow() throws Exception {
+        // 生成随机密钥
+        KeyGenerator keyGenerator = KeyGenerator.getInstance("AES");
+        // 128 192 256
+        keyGenerator.init(192, new SecureRandom());
+        SecretKey secretKey = keyGenerator.generateKey();
+        byte[] key = secretKey.getEncoded();
+
+//        System.out.println("Origin: " + key.length);
+        String hexKey = ShowBinary.byteToHex(key);
+
+        System.out.println("AES 密钥：" + hexKey);
+
+        String content = "KeyGenerator keyGenerator = KeyGenerator.getInstance(\"AES\");";
+        System.out.println("原文：" + content);
+
+        System.out.println("------");
+        byte[] ret = AESUtil.encrypt(hexKey, content.getBytes());
+//        System.out.println("密文：" + Base64.getEncoder().encodeToString(ret));
+        System.out.println("密文：" + ShowBinary.byteToHex(ret));
+
+        byte[] raw = AESUtil.decrypt(hexKey, ret);
+        System.out.println("原文：" + new String(raw));
+        Assert.assertEquals(content, new String(raw));
+    }
+
+
     @Test
     public void testStringEncrypt() throws Exception {
         // given