shiro加密算法

第一节的时候我介绍过，shiro有很多加密算法，如md5和sha，而且还支持加盐，使得密码的解析变得更有难度，更好的保障了数据的安全性。

这里我们要介绍的是md5算法，因为比较常用。首先我们来看看md5算法的各种实现方式：

package com.wujianwu.test;

import org.apache.shiro.crypto.hash.Md5Hash;
import org.apache.shiro.crypto.hash.SimpleHash;

public class TestMd5 {

    public static void main(String[] args) {
        String password = "123456";//要加密的字符串
        String salt = "wjw";//盐
        Integer hashIterations = 2;//散列次数
        //1.不加盐的md5
        Md5Hash md5 = new Md5Hash(password);
        System.out.println(md5.toString());

        //2.加盐的md5
        md5 = new Md5Hash(password, salt);
        System.out.println(md5.toString());

        //3.加盐再设置散列次数的md5
        md5 = new Md5Hash(password, salt, hashIterations);
        System.out.println(md5.toString());

        //4.利用SimpleHash来设置md5(上面三种都可以通过这个来设置，这里举例加盐加散列次数的)
        //第一个参数是算法名称，这里指定md5，第二个是要加密的密码，第三个参数是加盐，第四个是散列次数
        SimpleHash hash = new SimpleHash("md5", password, salt,hashIterations);
        System.out.println(hash.toString());
    }
}

上面列举了md5算法的各种实现，包括不加盐的，加盐的，加盐加散列次数的（从HashedCredentialsMatcher的源码可得知，默认散列次数为1），还有通过SimpleHash来实现md5的方式，下面看看它们的输出：

输出信息：

e10adc3949ba59abbe56e057f20f883e
7ca5a3bfd6fc151442219490509cb4d8
3d80e8a34ae898c07d3fb237bae26b7d
3d80e8a34ae898c07d3fb237bae26b7d

可以看到，不加盐、加盐、加盐加散列次数后的加密字段是不一样的，而它们的数据安全性也是递增的！但是注意散列次数不能设置过大，否则运行效率会变低。下面讲讲加密算法在realm中的应用。

一般我们在数据库保存的用户密码都是经过加密后的密码，所以我们想把加密后的用户信息传给shiro进行认证，就必须把该密码加密的算法、添加的盐以及散列的次数告诉shiro，因此我们需要配置realm里面的凭证匹配器credentialsMatcher，当用户将账号密码输进来时，shiro就会根据我们设置的加密规则对密码进行加密加盐，然后与realm中查询封装好的数据库数据进行比对认证。

public abstract class AuthenticatingRealm extends CachingRealm implements Initializable {

    //TODO - complete JavaDoc

    private static final Logger log = LoggerFactory.getLogger(AuthenticatingRealm.class);

    private static final AtomicInteger INSTANCE_COUNT = new AtomicInteger();

    /**
     * The default suffix appended to the realm name used for caching authentication data.
     *
     * @since 1.2
     */
    private static final String DEFAULT_AUTHORIZATION_CACHE_SUFFIX = ".authenticationCache";

    /**
     * Credentials matcher used to determine if the provided credentials match the credentials stored in the data store.
     */
    private CredentialsMatcher credentialsMatcher;

下面我们开始配置凭证匹配器：

shiro.ini:

[main]

#配置散列算法，用于用户输入身份和密码后进行加密然后与数据库数据比对
credentialsMatcher=org.apache.shiro.authc.credential.HashedCredentialsMatcher
credentialsMatcher.hashAlgorithmName=md5
credentialsMatcher.hashIterations=2
dataSource=com.mchange.v2.c3p0.ComboPooledDataSource
dataSource.driverClass=com.mysql.jdbc.Driver
dataSource.jdbcUrl=jdbc:mysql://localhost:3306/test
dataSource.user=root
dataSource.password=root
myRealm=com.wujianwu.realm.MyRealm
myRealm.credentialsMatcher=$credentialsMatcher
myRealm.dataSource=$dataSource
securityManager.realm=$myRealm

我们设置了一个凭证匹配器HashedCredentialsMatcher，然后再设置它里面的相关属性，如算法名称为md5，散列次数是两次，然后将设置好的凭证匹配器赋予我们自定义的realm，再修改一下我们的realm的部分代码，将数据库中的盐查询出来，并调用SimpleAuthenticationInfo的带有盐参数的构造方法来封装数据库查出来的用户数据（其实就是告诉shiro要比对的是加密后的信息），以下为新的myRealm:

package com.wujianwu.realm;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.sql.DataSource;

import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.AuthenticationInfo;
import org.apache.shiro.authc.AuthenticationToken;
import org.apache.shiro.authc.SimpleAuthenticationInfo;
import org.apache.shiro.authc.credential.CredentialsMatcher;
import org.apache.shiro.authz.AuthorizationInfo;
import org.apache.shiro.crypto.hash.SimpleHash;
import org.apache.shiro.realm.AuthorizingRealm;
import org.apache.shiro.subject.PrincipalCollection;
import org.apache.shiro.util.ByteSource;

import com.wujianwu.bean.User;

public class MyRealm  extends AuthorizingRealm{

    private DataSource dataSource;
    @Override
    public String getName() {
        // TODO Auto-generated method stub
        return "myRealm";
    }
    @Override
    protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken token) throws AuthenticationException {
        String userName = (String) token.getPrincipal();
        SimpleAuthenticationInfo info = null;
        User user = getUserInfo(userName);
        System.out.println("用户加密后的密码"+user.getPassword()+"==============");
        info = new SimpleAuthenticationInfo(userName, user.getPassword(), ByteSource.Util.bytes(user.getPasswordSalt()), getName());
        return info;
    }

    @Override
    protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection arg0) {
        // TODO Auto-generated method stub
        return null;
    }
    public DataSource getDataSource() {
        return dataSource;
    }
    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;
    }

    /**
     * 根据用户名从数据库查询出用户信息
     * @param username
     * @return
     */
    private User getUserInfo(String username){
        User user = new User();
        String sql = "select username,password,password_salt from users where username=?";
        Connection connection = null;
        PreparedStatement statement = null;
        ResultSet set = null;
        try {
            connection = dataSource.getConnection();
            statement = connection.prepareStatement(sql);
            statement.setString(1, username);
            set = statement.executeQuery();

            if(set.next()) {
                String username1 = set.getString(1);
                String password = set.getString(2);
                String salt = set.getString(3);
                user.setPassword(password);
                user.setUsername(username1);
                user.setPasswordSalt(salt);
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally {
            closeAll(connection, set, statement);
        }
        return user;
    }

    /**
     * 关闭资源
     * @param conn
     * @param set
     * @param statement
     */
    private void closeAll(Connection conn,ResultSet set,PreparedStatement statement) {
        try {
            if(set != null) {
                set.close();
            }
            if(statement != null) {
                statement.close();
            }
            if(conn != null) {
                conn.close();
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

}

注意SimpleAuthenticationInfo构造函数中的盐是ByteSource类型的，因此我们需要用接口ByteSource中的静态内部类Util下的bytes(String str)方法来将我们的盐转换成ByteSource类型。

设置好凭证匹配器，改好自定义的Realm，下面我们开始测试，还是熟悉的流程：

package com.wujianwu.test;

import org.apache.shiro.SecurityUtils;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.UsernamePasswordToken;
import org.apache.shiro.config.IniSecurityManagerFactory;
import org.apache.shiro.crypto.hash.Md5Hash;
import org.apache.shiro.crypto.hash.SimpleHash;
import org.apache.shiro.mgt.SecurityManager;
import org.apache.shiro.subject.Subject;
import org.apache.shiro.util.Factory;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class TestMyRealm {

    private static final Logger logger = LoggerFactory.getLogger(TestMyRealm.class);
    public static void main(String[] args) {
        Factory<SecurityManager> factory = new IniSecurityManagerFactory("classpath:shiro.ini");
        SecurityManager securityManager = factory.getInstance();
        SecurityUtils.setSecurityManager(securityManager);
        Subject subject = SecurityUtils.getSubject();
        UsernamePasswordToken token = new UsernamePasswordToken("zhangsan", "123456");
        try {
            subject.login(token);
            if(subject.isAuthenticated()) {
                logger.info("用户登录认证成功");
            }
        } catch (AuthenticationException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            logger.error("用户名或者密码错误，登录失败");
        }
    }
}

数据库的数据：

运行完控制台输出如下：

2019-07-28 19:59:30,535 INFO [com.mchange.v2.log.MLog] - MLog clients using slf4j logging.
2019-07-28 19:59:30,963 INFO [com.mchange.v2.c3p0.C3P0Registry] - Initializing c3p0-0.9.5.2 [built 08-December-2015 22:06:04 -0800; debug? true; trace: 10]
2019-07-28 19:59:31,055 INFO [org.apache.shiro.config.IniSecurityManagerFactory] - Realms have been explicitly set on the SecurityManager instance - auto-setting of realms will not occur.
2019-07-28 19:59:31,085 INFO [com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource] - Initializing c3p0 pool... com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 3, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, contextClassLoaderSource -> caller, dataSourceName -> 2zm2h7a4fnv3mn329o49|180bc464, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> com.mysql.jdbc.Driver, extensions -> {}, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, forceSynchronousCheckins -> false, forceUseNamedDriverClass -> false, identityToken -> 2zm2h7a4fnv3mn329o49|180bc464, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:mysql://localhost:3306/test, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 0, maxIdleTimeExcessConnections -> 0, maxPoolSize -> 15, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 3, numHelperThreads -> 3, preferredTestQuery -> null, privilegeSpawnedThreads -> false, properties -> {user=******, password=******}, propertyCycle -> 0, statementCacheNumDeferredCloseThreads -> 0, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, unreturnedConnectionTimeout -> 0, userOverrides -> {}, usesTraditionalReflectiveProxies -> false ]
用户加密后的密码3d80e8a34ae898c07d3fb237bae26b7d==============
2019-07-28 19:59:31,399 INFO [org.apache.shiro.session.mgt.AbstractValidatingSessionManager] - Enabling session validation scheduler...
2019-07-28 19:59:31,405 INFO [com.wujianwu.test.TestMyRealm] - 用户登录认证成功 

可以看到，我们模拟的用户输入的账号是zhangsan，密码是123456，但数据库中的密码是加密加盐后的密码，所以我们给realm配置了加密算法的规则，让它将我们传过去的密码进行了同样的加密加盐（这里盐不需要我们设置，是从数据库中查询出来的），然后再和数据库的数据进行比对认证，因此这里认证是成功的（123456进行md5加密和wjw加盐后然后再散列2次就是这一串东西了：3d80e8a34ae898c07d3fb237bae26b7d，至于内部如何实现，有兴趣的大佬可以去看一下《算法》这本书= =）

以上就是散列算法（加密算法）在shiro中的使用Demo，如果有什么补充或者修改的请在评论区留言，谢谢！