标签：static ash 构造 des air except tac image def
针对加密解密的算法，学了一下，首先是base64编码与解码，然后针对AES,RSA,MD5做了一个工具类，对公私密钥的生成也抽象成一个工具类，现在进行分享一下。
一：程序大纲
1.结构
二：程序
1.Base64Util
1 package crypt.code; 2 3 import org.apache.commons.codec.binary.Base64; 4 5 import org.slf4j.Logger; 6 import org.slf4j.LoggerFactory; 7 import org.testng.annotations.Test; 8 9 import java.io.UnsupportedEncodingException; 10 11 public class Base64Util { 12 private static final Logger logger = LoggerFactory.getLogger(Base64Util.class); 13 14 //base64 编码 15 public static String encode(byte[] bytes) { 16 return new String(Base64.encodeBase64(bytes)); 17 } 18 public static byte[] encodeByte(byte[] bytes){ 19 return Base64.encodeBase64(bytes); 20 } 21 22 //base64 解码 23 public static String decode(byte[] bytes) { 24 return new String(Base64.decodeBase64(bytes)); 25 } 26 public static byte[] decode(String str){ 27 return Base64.decodeBase64(str); 28 } 29 30 31 32 //测试 33 @Test 34 public void testCrypt() throws UnsupportedEncodingException { 35 String str = "base demo"; 36 String enCode = encode(str.getBytes("utf-8")); 37 logger.info("encode:{}",enCode); 38 39 String deCode = decode(enCode.getBytes("utf-8")); 40 logger.info("decode:{}",deCode); 41 } 42 43 }
2.AesCryptUtil
1 package crypt.rsa; 2 3 import org.slf4j.Logger; 4 import org.slf4j.LoggerFactory; 5 import org.testng.annotations.Test; 6 7 import javax.crypto.Cipher; 8 import javax.crypto.KeyGenerator; 9 import javax.crypto.SecretKey; 10 import javax.crypto.spec.SecretKeySpec; 11 import java.io.UnsupportedEncodingException; 12 import java.security.SecureRandom; 13 14 public class AesCryptUtil { 15 private static final Logger logger = LoggerFactory.getLogger(AesCryptUtil.class); 16 private static final String DEFAULT_CHARSET = "UTF-8"; 17 private static final String AES = "AES"; 18 private static String KEY = "123456"; //加密密码 19 20 //对外提供的加密 21 public static String encrypt(String str, String key) throws Exception { 22 return doAes(str, key, Cipher.ENCRYPT_MODE); 23 } 24 25 //对外提供的解密 26 public static String decrypt(String str, String key) throws Exception { 27 return doAes(str, key, Cipher.DECRYPT_MODE); 28 } 29 30 /** 31 * 加密与解密 32 * @param str 33 * @param key 34 * @param mode 35 * @return 36 * @throws Exception 37 */ 38 private static String doAes(String str,String key, int mode) throws Exception { 39 byte[] content; 40 //判断加解密 41 if(Cipher.ENCRYPT_MODE == mode){ 42 //是加密 43 content = str.getBytes(DEFAULT_CHARSET); 44 }else { 45 content = parseHexstrToByte(str); 46 } 47 //构造密钥生成器 48 KeyGenerator keyGenerator = KeyGenerator.getInstance(AES); 49 //初始化密钥生成器 50 keyGenerator.init(128,new SecureRandom(key.getBytes())); 51 //产生原始对称密钥 52 SecretKey secretKey = keyGenerator.generateKey(); 53 //取货原始对此密钥的数组 54 byte[] secretKeyByte = secretKey.getEncoded(); 55 //根据数组生成AES密钥 56 SecretKeySpec secretKeySpec = new SecretKeySpec(secretKeyByte, AES); 57 //根据指定算法自成密码器 58 Cipher cipher = Cipher.getInstance(AES); 59 //初始化密码器 60 cipher.init(mode,secretKeySpec); 61 byte[] result = cipher.doFinal(content); 62 if(Cipher.ENCRYPT_MODE == mode){ 63 return parseByteToHexstr(result); 64 }else{ 65 return new String(result,DEFAULT_CHARSET); 66 } 67 } 68 69 /** 70 * 二进制转为十六进制 71 * @param result 72 * @return 73 */ 74 public static String parseByteToHexstr(byte[] result){ 75 StringBuilder sb = new StringBuilder(); 76 for(int i=0; i<result.length; i++){ 77 String hex = Integer.toHexString(result[i]&0xff); 78 if(hex.length()==1) 79 hex = ‘0‘+hex; 80 sb.append(hex.toUpperCase()); 81 } 82 return sb.toString(); 83 } 84 85 /** 86 * 十六进制转二进制 87 * @param hexStr 88 * @return 89 */ 90 public static byte[] parseHexstrToByte(String hexStr){ 91 if(hexStr.length()<1) 92 return null; 93 byte[] result = new byte[hexStr.length()/2]; 94 for(int i=0; i<hexStr.length()/2; i++){ 95 int high = Integer.parseInt(hexStr.substring(i*2,i*2+1),16); 96 int low = Integer.parseInt(hexStr.substring(i*2+1,i*2+2),16); 97 result[i] = (byte)(high*16 +low); 98 } 99 return result; 100 } 101 102 @Test 103 public void test() throws Exception { 104 String content = "test aes"; 105 String encrypt = encrypt(content, KEY); 106 logger.info("test-encrypt:{}",encrypt); 107 String decrypt = decrypt(encrypt, KEY); 108 logger.info("test-decrypt:{}",decrypt); 109 } 110 111 }
3.生成公私密钥
1 package crypt.rsa; 2 3 import org.apache.commons.codec.binary.Base64; 4 import org.slf4j.Logger; 5 import org.slf4j.LoggerFactory; 6 7 import java.security.KeyPair; 8 import java.security.KeyPairGenerator; 9 import java.security.NoSuchAlgorithmException; 10 import java.security.SecureRandom; 11 import java.security.interfaces.RSAPrivateKey; 12 import java.security.interfaces.RSAPublicKey; 13 import java.util.HashMap; 14 import java.util.Map; 15 16 /** 17 * @Description 这个方法单独抽取出来使用 18 */ 19 public class GeneKeyPair { 20 private static final Logger logger = LoggerFactory.getLogger(RsaCryptUtils.class); 21 private static Map<String,String> keyMap =new HashMap<String, String>(); 22 /** 23 * 生成公私密钥 24 * @throws NoSuchAlgorithmException 25 */ 26 public static void geneKeyPair() throws NoSuchAlgorithmException { 27 KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA"); 28 //初始化密钥生成器，密钥的大小是96-1024位 29 keyPairGenerator.initialize(1024, new SecureRandom()); 30 //生成一个密钥对 31 KeyPair keyPair = keyPairGenerator.generateKeyPair(); 32 RSAPrivateKey privateKey = (RSAPrivateKey)keyPair.getPrivate(); 33 RSAPublicKey publicKey = (RSAPublicKey)keyPair.getPublic(); 34 // 35 String privateKeyStr = new String(Base64.encodeBase64(privateKey.getEncoded())); 36 String publicKeyStr = new String(Base64.encodeBase64(publicKey.getEncoded())); 37 // 38 keyMap.put("0",privateKeyStr); 39 keyMap.put("1",publicKeyStr); 40 } 41 42 /** 43 * 返回公私密钥 44 * @return 45 * @throws NoSuchAlgorithmException 46 */ 47 public static Map getKey() throws NoSuchAlgorithmException { 48 geneKeyPair(); 49 return keyMap; 50 } 51 }
4.Md5Util
1 package crypt.rsa; 2 3 import org.apache.commons.codec.digest.DigestUtils; 4 import org.testng.annotations.Test; 5 6 import java.security.MessageDigest; 7 8 /** 9 * @Description MD5是不可逆的，单向哈希计算 10 */ 11 public class Md5Util { 12 13 /** 14 * 方式一，使用commons-codec包 15 * @param str 16 * @return 17 */ 18 public static String encrypt(String str){ 19 return DigestUtils.md5Hex(str); 20 } 21 22 /** 23 * 方式二，使用MessageDigest 24 * @param str 25 * @return 26 */ 27 public static String encrypt2(String str){ 28 String hexStr = ""; 29 try { 30 //MessageDigest 类为应用程序提供信息摘要算法的功能，如 MD5 或 SHA 算法。 31 // 信息摘要是安全的单向哈希函数，它接收任意大小的数据，并输出固定长度的哈希值。 32 MessageDigest messageDigest = MessageDigest.getInstance("MD5"); 33 //完成哈希计算 34 byte[] digest = messageDigest.digest(str.getBytes("UTF-8")); 35 hexStr = AesCryptUtil.parseByteToHexstr(digest).toLowerCase(); 36 }catch (Exception e){ 37 e.printStackTrace(); 38 } 39 return hexStr; 40 } 41 42 /** 43 * 测试 44 */ 45 @Test 46 public void test(){ 47 String str = "md5 test"; 48 String encrypt = encrypt(str); 49 String encrypt2 = encrypt2(str); 50 System.out.println(encrypt); 51 System.out.println(encrypt2); 52 } 53 }
5.RsaCryptUtil
1 package crypt.rsa; 2 3 import crypt.code.Base64Util; 4 import org.apache.commons.codec.binary.Base64; 5 import org.slf4j.Logger; 6 import org.slf4j.LoggerFactory; 7 import org.testng.annotations.Test; 8 import javax.crypto.Cipher; 9 import java.security.*; 10 import java.security.interfaces.RSAPrivateKey; 11 import java.security.interfaces.RSAPublicKey; 12 import java.security.spec.PKCS8EncodedKeySpec; 13 import java.security.spec.X509EncodedKeySpec; 14 import java.util.HashMap; 15 import java.util.Map; 16 17 /** 18 * @Description 公钥加密，私钥解密 19 */ 20 public class RsaCryptUtil { 21 private static final Logger logger = LoggerFactory.getLogger(RsaCryptUtil.class); 22 private static Map<String,String> keyMap =new HashMap<String, String>(); 23 24 /** 25 * 生成公私密钥，在实际中，可以生成一对公司公私密钥使用 26 * @throws NoSuchAlgorithmException 27 */ 28 public static void geneKeyPair() throws NoSuchAlgorithmException { 29 KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA"); 30 //初始化密钥生成器，密钥的大小是96-1024位 31 keyPairGenerator.initialize(1024, new SecureRandom()); 32 //生成一个密钥对 33 KeyPair keyPair = keyPairGenerator.generateKeyPair(); 34 RSAPrivateKey privateKey = (RSAPrivateKey)keyPair.getPrivate(); 35 RSAPublicKey publicKey = (RSAPublicKey)keyPair.getPublic(); 36 // 37 String privateKeyStr = new String(Base64.encodeBase64(privateKey.getEncoded())); 38 String publicKeyStr = new String(Base64.encodeBase64(publicKey.getEncoded())); 39 // 40 keyMap.put("0",privateKeyStr); 41 keyMap.put("1",publicKeyStr); 42 } 43 44 /** 45 * 使用公钥加密 46 * @param str 47 * @param publicKey 48 * @return 49 */ 50 public static String encrypt(String str, String publicKey) throws Exception { 51 //base64编码的公钥 52 byte[] decoded = Base64.decodeBase64(publicKey); 53 RSAPublicKey pubKey = (RSAPublicKey) KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(decoded)); 54 //RSA加密 55 Cipher cipher = Cipher.getInstance("RSA"); 56 cipher.init(Cipher.ENCRYPT_MODE, pubKey); 57 String outStr = Base64.encodeBase64String(cipher.doFinal(str.getBytes("UTF-8"))); 58 return outStr; 59 } 60 61 /** 62 * 私钥解密 63 * @param str 64 * @param privateKey 65 * @return 66 */ 67 public static String decrypt(String str, String privateKey) throws Exception { 68 //对字符串进行64位解码 69 byte[] inputByte = Base64Util.decode(str); 70 //解码私钥 71 byte[] decoded = Base64Util.decode(privateKey); 72 RSAPrivateKey priKey = (RSAPrivateKey) KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(decoded)); 73 //RSA解密 74 Cipher cipher = Cipher.getInstance("RSA"); 75 cipher.init(Cipher.DECRYPT_MODE, priKey); 76 String outStr = new String(cipher.doFinal(inputByte)); 77 return outStr; 78 } 79 80 //测试 81 @Test 82 public void test() throws Exception { 83 geneKeyPair(); 84 logger.info("geneKeyPair-privateKeyStr:{}",keyMap.get("0")); 85 logger.info("geneKeyPair-publicKeyStr:{}",keyMap.get("1")); 86 // 87 String message = "crypt test demo"; 88 String enMessage = encrypt(message,keyMap.get("1")); 89 logger.info("test-enMessage:{}",enMessage); 90 String deMessage =decrypt(enMessage,keyMap.get("0")); 91 logger.info("test-deMessage:{}",deMessage); 92 } 93 }
6.扩展一下RSA
1 package crypt.rsa; 2 3 import crypt.code.Base64Util; 4 import org.apache.commons.codec.binary.Base64; 5 import org.slf4j.Logger; 6 import org.slf4j.LoggerFactory; 7 import org.springframework.beans.factory.annotation.Autowired; 8 import org.testng.annotations.Test; 9 10 import javax.crypto.Cipher; 11 import java.security.*; 12 import java.security.interfaces.RSAPrivateKey; 13 import java.security.interfaces.RSAPublicKey; 14 import java.security.spec.PKCS8EncodedKeySpec; 15 import java.security.spec.X509EncodedKeySpec; 16 import java.util.HashMap; 17 import java.util.Map; 18 19 /** 20 * @Description 扩展一下，不仅仅是RsaCryptUtil的公钥加密，私钥解密 21 * 私钥加密，公钥解密 22 * 两种方法都存在使用的场合 23 */ 24 public class RsaCryptUtils { 25 private static final Logger logger = LoggerFactory.getLogger(RsaCryptUtils.class); 26 27 /** 28 * 使用私钥加密 29 * @param str 30 * @param privateKey 31 * @return 32 */ 33 public static String encrypt(String str, String privateKey) throws Exception { 34 //base64编码的公钥 35 byte[] decoded = Base64.decodeBase64(privateKey); 36 RSAPrivateKey priKey = (RSAPrivateKey) KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(decoded)); 37 //RSA加密 38 Cipher cipher = Cipher.getInstance("RSA"); 39 cipher.init(Cipher.ENCRYPT_MODE, priKey); 40 String outStr = Base64.encodeBase64String(cipher.doFinal(str.getBytes("UTF-8"))); 41 return outStr; 42 } 43 44 /** 45 * 公钥解密 46 * @param str 47 * @param publicKey 48 * @return 49 */ 50 public static String decrypt(String str, String publicKey) throws Exception { 51 //对字符串进行64位解码 52 byte[] inputByte = Base64Util.decode(str); 53 //解码私钥 54 byte[] decoded = Base64Util.decode(publicKey); 55 RSAPublicKey pubKey = (RSAPublicKey) KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(decoded)); 56 //RSA解密 57 Cipher cipher = Cipher.getInstance("RSA"); 58 cipher.init(Cipher.DECRYPT_MODE, pubKey); 59 String outStr = new String(cipher.doFinal(inputByte)); 60 return outStr; 61 } 62 63 //测试 64 @Test 65 public void test() throws Exception { 66 Map<String, String> keyMap = GeneKeyPair.getKey(); 67 logger.info("geneKeyPair-privateKeyStr:{}",keyMap.get("0")); 68 logger.info("geneKeyPair-publicKeyStr:{}",keyMap.get("1")); 69 // 70 String message = "crypt test demo"; 71 String enMessage = encrypt(message,keyMap.get("0")); 72 logger.info("test-enMessage:{}",enMessage); 73 String deMessage =decrypt(enMessage,keyMap.get("1")); 74 logger.info("test-deMessage:{}",deMessage); 75 } 76 }
标签：static ash 构造 des air except tac image def
原文地址：https://www.cnblogs.com/juncaoit/p/11170945.html
