什么是 JWT
JSON Web Token（JWT）是目前最流行的跨域身份验证解决方案
JSON Web Token Introduction - jwt.ioLearn about JSON Web Tokens, what are they, how they work, when and why you should use them.
https://jwt.io/introduction
一、常见会话
cookie、session、token
-cookie：客户端浏览器的键值对
-session：服务的的键值对（djangosession表，内存中,文件，缓存数据库）
-token：服务的生成的加密字符串，如果存在客户端浏览器上，就叫cookie
-三部分：头，荷载，签名
-签发：登录成功，签发
-认证：认证类中认证
jwt （Json web token）
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiYWRtaW4iOnRydWV9.TJVA95OrM7E2cBab30RMHrHDcEfxjoYZgeFONFh7HgQ
二、base64编码和解码
base64并不是一种加密反射，只是编码解码方式
- 字符串，可以转成base64编码格式：eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9
- eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9 解码成base64
import json
import base64d = {'user_id': 1, 'username': "lqz"}d_str = json.dumps(d)print(d_str)
# # 对字符串进行bashe64 编码
res=base64.b64encode(bytes(d_str,encoding='utf-8'))
print(res) # eyJ1c2VyX2lkIjogMSwgInVzZXJuYW1lIjogImxxeiJ9# 解码
res=base64.b64decode('TJVA95OrM7E2cBab30RMHrHDcEfxjoYZgeFONFh7HgQ=')
print(res)ps:记住： base64 编码，长度一定是4的倍数。如果不够，用 = 补齐
base64的用途
- 互联网中，前后端数据交互，使用base64编码
- jwt 字符串使用base64编码
- 互联网中一些图片，使用base64编码
s = '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'
res = base64.b64decode(s)
with open('code.png', 'wb') as f:f.write(res)三、 JWT认证
在用户注册或登录后，我们想记录用户的登录状态，或者为用户创建身份认证的凭证。我们不再使用Session认证机制，而使用Json Web Token（本质就是token）认证机制
使用jwt认证和使用session认证的区别
加密原理
在对称加密的时代，加密和解密用的是同一个密钥，这个密钥既用于加密，又用于解密。这样做有一个明显的缺点，如果两个人之间传输文件，两个人都要知道密钥，如果是三个人呢，五个人呢？于是就产生了非对称加密，用一个密钥进行加密(公钥)，用另一个密钥进行解密(私钥)
1.公钥私钥原理
张三有两把钥匙，一把是公钥，另一把是私钥。
张三把公钥送给他的朋友们李四、王五、赵六每人一把。
李四要给张三写一封保密的信。她写完后用张三的公钥加密，就可以达到保密的效果。
张三收信后，用私钥解密，就看到了信件内容。这里要强调的是，只要张三的私钥不泄露，这封信就是安全的，即使落在别人手里，也无法解密。
张三给李四回信，决定采用“数字签名”。他写完后先用Hash函数，生成信件的摘要(digest)。然后利用私钥将摘要进行加密，张三将这个签名，附在信件下面，一起发给李四。
李四收信后，取下数字签名，用张三的公钥解密，得到信件的摘要。由此证明，这封信确实是张三发出的。李四再对信件本身使用Hash函数，将得到的结果，与上一步得到的摘要进行对比。如果两者一致，就证明这封信未被修改过。
四、JWT生产公钥与私钥
找到JDK环境的keytool（证书管理工具）
生成私钥
keytool -genkeypair -alias test110 -keyalg RSA -keypass miyaomima -keystore xc.keystore -storepass miyaokumima
| 建值 | 解释说明 | 测试用例 |
| -alias | 证书的别名 | test110 |
| -keyalg | 使用的hash算法 | RSA |
| -keypass | 密钥的访问密码 | miyaomima |
| -keystore | 生成的文件的名字 | xc.keystore |
| xc.keystore | 保存了生成的证书 | |
| -storepass | 密钥库的访问密码 | miyaokumima |
Windows系统需以管理员身份运行
查看证书文件是否生成成功
查看密钥
keytool -list -keystore xc.keystore
删除别名
keytool -delete -alias test110 -keystore xc.keystore
生成公钥
配置openssl
Win32/Win64 OpenSSL Installer for Windows - Shining Light Productionshttp://slproweb.com/products/Win32OpenSSL.html找一个合适自己计算机版本的进行配置
点击下载
这里小编使用默认路径进行安装
配置path环境变量
本教程配置在C:\Program Files\OpenSSL-Win64\bin
cmd进入xc.keystore文件所在目录执行命令 | 右键终端打开
keytool -list -rfc --keystore xc.keystore | openssl x509 -inform pem -pubkey
将上边的公钥拷贝到文本public.key文件中，合并为一行,可以将它放到需要实现授权认证的工程中
Attention
证书文件不要放在有中文路径下
所有文字都要在同一行
五、项目实战
引入JWT的依赖
<dependency><groupId>io.jsonwebtoken</groupId><artifactId>jjwt-api</artifactId><version>0.10.5</version>
</dependency>
<dependency><groupId>io.jsonwebtoken</groupId><artifactId>jjwt-impl</artifactId><version>0.10.5</version><scope>runtime</scope>
</dependency>
<dependency><groupId>io.jsonwebtoken</groupId><artifactId>jjwt-jackson</artifactId><version>0.10.5</version><scope>runtime</scope>
</dependency>引入其他依赖
<dependency><groupId>joda-time</groupId><artifactId>joda-time</artifactId><version>2.9.4</version>
</dependency>
<dependency><groupId>cn.hutool</groupId><artifactId>hutool-all</artifactId><version>5.7.16</version>
</dependency>
<dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>1.2.54</version>
</dependency>创建User对象
public class UserInfo {private Long id;//用户IDprivate String username;//用户名称private String role;//用户角色public Long getId() {return id;}public void setId(Long id) {this.id = id;}public String getUsername() {return username;}public void setUsername(String username) {this.username = username;}public String getRole() {return role;}public void setRole(String role) {this.role = role;}
}创建JWT工具类
import cn.hutool.core.util.ObjectUtil;
import cn.hutool.json.JSONUtil;
import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jws;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import org.joda.time.DateTime;import java.security.PrivateKey;
import java.security.PublicKey;
import java.util.Base64;
import java.util.UUID;public class JwtUtils {private static final String JWT_PAYLOAD_USER_KEY = "user";/*** 私钥加密token** @param info 载荷中的数据* @param privateKey 私钥* @param expire 过期时间，单位分钟* @return JWT*/public static String generateTokenExpireInMinutes(Object info, PrivateKey privateKey, int expire) {return Jwts.builder()//claim: 往Jwt的载荷存入数据.claim(JWT_PAYLOAD_USER_KEY, ObjectUtil.toString(info))//往Jwt的载荷存入数据，设置固定id的key.setId(createJTI())//往Jwt的载荷存入数据，设置固定exp的key.setExpiration(DateTime.now().plusMinutes(expire).toDate())//设置token的签名.signWith(privateKey, SignatureAlgorithm.RS256).compact();}/*** 私钥加密token** @param info 载荷中的数据* @param privateKey 私钥* @param expire 过期时间，单位秒* @return JWT*/public static String generateTokenExpireInSeconds(Object info, PrivateKey privateKey, int expire) {return Jwts.builder().claim(JWT_PAYLOAD_USER_KEY, ObjectUtil.toString(info)).setId(createJTI()).setExpiration(DateTime.now().plusSeconds(expire).toDate()).signWith(privateKey, SignatureAlgorithm.RS256).compact();}/*** 公钥解析token** @param token 用户请求中的token* @param publicKey 公钥* @return Jws<Claims>*/private static Jws<Claims> parserToken(String token, PublicKey publicKey) {return Jwts.parser().setSigningKey(publicKey).parseClaimsJws(token);}private static String createJTI() {return new String(Base64.getEncoder().encode(UUID.randomUUID().toString().getBytes()));}/*** 获取token中的用户信息** @param token 用户请求中的令牌* @param publicKey 公钥* @return 用户信息*/public static <T> Payload<T> getInfoFromToken(String token, PublicKey publicKey, Class<T> userType) {Jws<Claims> claimsJws = parserToken(token, publicKey);Claims body = claimsJws.getBody();Payload<T> claims = new Payload<>();claims.setId(body.getId());claims.setInfo(JSONUtil.toBean(body.get(JWT_PAYLOAD_USER_KEY).toString(), userType));claims.setExpiration(body.getExpiration());return claims;}/*** 获取token中的载荷信息** @param token 用户请求中的令牌* @param publicKey 公钥* @return 用户信息*/public static <T> Payload<T> getInfoFromToken(String token, PublicKey publicKey) {Jws<Claims> claimsJws = parserToken(token, publicKey);Claims body = claimsJws.getBody();Payload<T> claims = new Payload<>();claims.setId(body.getId());claims.setExpiration(body.getExpiration());return claims;}
}
创建RSA工具类
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.security.*;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Base64;public class RsaUtils {private static final int DEFAULT_KEY_SIZE = 2048;/*** 从文件中读取公钥** @param filename 公钥保存路径，相对于classpath* @return 公钥对象* @throws Exception*/public static PublicKey getPublicKey(String filename) throws Exception {byte[] bytes = readFile(filename);return getPublicKey(bytes);}/*** 从文件中读取密钥** @param filename 私钥保存路径，相对于classpath* @return 私钥对象* @throws Exception*/public static PrivateKey getPrivateKey(String filename) throws Exception {byte[] bytes = readFile(filename);return getPrivateKey(bytes);}/*** 获取公钥** @param bytes 公钥的字节形式* @return* @throws Exception*/private static PublicKey getPublicKey(byte[] bytes) throws Exception {bytes = Base64.getDecoder().decode(bytes);X509EncodedKeySpec spec = new X509EncodedKeySpec(bytes);KeyFactory factory = KeyFactory.getInstance("RSA");return factory.generatePublic(spec);}/*** 获取密钥** @param bytes 私钥的字节形式* @return* @throws Exception*/private static PrivateKey getPrivateKey(byte[] bytes) throws NoSuchAlgorithmException, InvalidKeySpecException {bytes = Base64.getDecoder().decode(bytes);PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(bytes);KeyFactory factory = KeyFactory.getInstance("RSA");return factory.generatePrivate(spec);}/*** 根据密文，生存rsa公钥和私钥,并写入指定文件** @param publicKeyFilename 公钥文件路径* @param privateKeyFilename 私钥文件路径* @param secret 生成密钥的密文*/public static void generateKey(String publicKeyFilename, String privateKeyFilename, String secret, int keySize) throws Exception {KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");SecureRandom secureRandom = new SecureRandom(secret.getBytes());keyPairGenerator.initialize(Math.max(keySize, DEFAULT_KEY_SIZE), secureRandom);KeyPair keyPair = keyPairGenerator.genKeyPair();// 获取公钥并写出byte[] publicKeyBytes = keyPair.getPublic().getEncoded();publicKeyBytes = Base64.getEncoder().encode(publicKeyBytes);writeFile(publicKeyFilename, publicKeyBytes);// 获取私钥并写出byte[] privateKeyBytes = keyPair.getPrivate().getEncoded();privateKeyBytes = Base64.getEncoder().encode(privateKeyBytes);writeFile(privateKeyFilename, privateKeyBytes);}private static byte[] readFile(String fileName) throws Exception {return Files.readAllBytes(new File(fileName).toPath());}private static void writeFile(String destPath, byte[] bytes) throws IOException {File dest = new File(destPath);if (!dest.exists()) {dest.createNewFile();}Files.write(dest.toPath(), bytes);}
}创建PayLoad工具类
import java.util.Date;public class Payload<T>{private String id;private T info;private Date expiration;public String getId() {return id;}public void setId(String id) {this.id = id;}public T getInfo() {return info;}public void setInfo(T info) {this.info = info;}public Date getExpiration() {return expiration;}public void setExpiration(Date expiration) {this.expiration = expiration;}
}创建测试类
import com.alibaba.fastjson.JSONObject;public class Test {private static final String localPath = "\\main\\java\\com\\coldwind\\xutils\\jwt\\";public static void generateKey() {String proPath = System.getProperty("user.dir") + "\\src";proPath = proPath.replaceAll("\\\\", "\\\\\\\\");String keyPath = proPath+ localPath;String priKey = keyPath + "private.key";String pubKey = keyPath + "public.key";String secret = "123456";try {RsaUtils.generateKey(pubKey, priKey, secret, 2048);} catch (Exception e) {e.printStackTrace();}}public static void test() throws Exception {String proPath = System.getProperty("user.dir") + "\\src";proPath = proPath.replaceAll("\\\\", "\\\\\\\\");String keyPath = proPath+localPath;UserInfo userInfo = new UserInfo();userInfo.setUsername("admin");userInfo.setId(1L);String token = JwtUtils.generateTokenExpireInMinutes(JSONObject.toJSONString(userInfo), RsaUtils.getPrivateKey(keyPath+"private.key"), 10);System.out.println(token);Payload<UserInfo> userInfoPayload = JwtUtils.getInfoFromToken(token, RsaUtils.getPublicKey(keyPath+"public.key"),UserInfo.class);System.out.println(JSONObject.toJSONString(userInfoPayload));}public static void main(String[] args) throws Exception {test();}}
第一步：先在执行目录下生成公钥、私钥
第二步：模拟私钥加密
第三部：模拟公钥解密
执行效果
eyJhbGciOiJSUzI1NiJ9.eyJ1c2VyIjoie1wiaWRcIjoxLFwidXNlcm5hbWVcIjpcImFkbWluXCJ9IiwianRpIjoiTXprMVpEQmtOR010TWpZMFpTMDBPREl3TFRsaFpEZ3ROamRqTkdNelkyUTVNVEE1IiwiZXhwIjoxNzE3ODk3NTU2fQ.TrsJToMTUpkP6DbtyCL16-2d1WTTxPmOhb4BQyAFB6_nUg94xKu6q-lSfZNi3e7BmGxNrJYYNUyJZxaMO20ZQ88OJdeYbNfZ8ixxv2zw8QrmIFTGzHLqximXvl6kMZWEd_ArKRi2ba5NDQlTAvqJfQSv5hjiY-Rug_RX_Pd4ak81kVWOYOhJUMvsfoVlp6typoiFSWdjp024mkux4GtQfexZy0_CbLTX5KI4bVioSgxREPAhH68bmx-LcQQ9GEtcCidEZu0FsA6ubqnE0IWw5g6TJhOnuNdZOT2QWsv9WPaxhOJllV1mAqeXwnJufSZa-VUYgVjQhNnAWXbcNBSUqA
{"expiration":1717897556000,"id":"Mzk1ZDBkNGMtMjY0ZS00ODIwLTlhZDgtNjdjNGMzY2Q5MTA5","info":{"id":1,"username":"admin"}}
