前言

一些敏感信息存入数据需要进行加密处理，比如电话号码，身份证号码等，从数据库取出到前端展示时需要解密，如果分别在存入取出时去做处理，会很繁锁，至此，我查了很多相关资料，最后得到一个比较完美的解决方案。

实现步骤

定义注解

1、实体注解@SensitiveEntity

bash 复制代码

import java.lang.annotation.*;

@Target({ElementType.TYPE, ElementType.PARAMETER})
@Retention(RetentionPolicy.RUNTIME)
@Inherited
@Documented
public @interface SensitiveEntity {

}

2、字段注解@SensitiveEntity

bash 复制代码

import java.lang.annotation.*;

@Target({ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
@Inherited
@Documented
public @interface SensitiveField {

}

加密工具类

AesFieldUtils.java

bash 复制代码

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.util.Base64Utils;

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import java.util.regex.Matcher;
import java.util.regex.Pattern;


@Slf4j
@Component
public class AesFieldUtils {
    /**
     * 加密算法
     */
    private final String KEY_ALGORITHM = "AES";
    /**
     * 算法/模式/补码方式
     */
    private final String DEFAULT_CIPHER_ALGORITHM = "AES/ECB/PKCS5Padding";
    /**
     * 编码格式
     */
    private final String CODE = "utf-8";
    /**
     * base64验证规则
     */
    private static final String BASE64_RULE = "^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)=?$";

    /**
     * 正则验证对象
     */
    private static final Pattern PATTERN = Pattern.compile(BASE64_RULE);
    /**
     * 加解密 密钥key
     */
    @Value("${aes.key}")
    private String key;


    /**
     * @param content 加密字符串
     * @return 加密结果
     */
    public String encrypt(String content) {
        return encrypt(content, key);
    }

    /**
     * 加密
     *
     * @param content 加密参数
     * @param key     加密key
     * @return 结果字符串
     */
    public String encrypt(String content, String key) {
        //判断如果已经是base64加密字符串则返回原字符串
        if (isBase64(content)) {
            return content;
        }
        // 为了安全起见，暂时不加密，需要时再放开
        //return content;
         byte[] encrypted = encrypt2bytes(content, key);
        if (null == encrypted || encrypted.length < 1) {
            log.error("加密字符串[{}]转字节为null", content);
            return null;
        }
        return Base64Utils.encodeToString(encrypted);

    }

    /**
     * @param content 加密字符串
     * @param key     加密key
     * @return 返回加密字节
     */
    public byte[] encrypt2bytes(String content, String key) {
        try {
            byte[] raw = key.getBytes(CODE);
            SecretKeySpec secretKeySpec = new SecretKeySpec(raw, KEY_ALGORITHM);
            Cipher cipher = Cipher.getInstance(DEFAULT_CIPHER_ALGORITHM);
            cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec);
            return cipher.doFinal(content.getBytes(CODE));
        } catch (Exception e) {
            log.error("failed to encrypt: {} of {}", content, e);
            return null;
        }
    }

    /**
     * @param content 加密字符串
     * @return 返回加密结果
     */
    public String decrypt(String content) {
        try {
            return decrypt(content, key);
        } catch (Exception e) {
            log.error("failed to decrypt: {}, e: {}", content, e);
            return null;
        }
    }

    /**
     * 解密
     *
     * @param content 解密字符串
     * @param key     解密key
     * @return 解密结果
     */
    public String decrypt(String content, String key) throws Exception {
        //不是base64格式字符串则不进行解密
        if (!isBase64(content)) {
            return content;
        }
        // 为了安全起见，暂时不加密解密，需要时再放开
        //return content;
        return decrypt(Base64Utils.decodeFromString(content), key);
    }

    /**
     * @param content 解密字节
     * @param key     解密key
     * @return 返回解密内容
     */
    public String decrypt(byte[] content, String key) throws Exception {
        if (key == null) {
            log.error("AES key should not be null");
            return null;
        }

        byte[] raw = key.getBytes(CODE);
        SecretKeySpec keySpec = new SecretKeySpec(raw, KEY_ALGORITHM);
        Cipher cipher = Cipher.getInstance(DEFAULT_CIPHER_ALGORITHM);
        cipher.init(Cipher.DECRYPT_MODE, keySpec);
        try {
            byte[] original = cipher.doFinal(content);
            return new String(original, CODE);
        } catch (Exception e) {
            log.error("failed to decrypt content: {}/ key: {}, e: {}", content, key, e);
            return null;
        }
    }

    /**
     * 判断是否为 base64加密
     *
     * @param str 参数
     * @return 结果
     */
    public static boolean isBase64(String str) {
        Matcher matcher = PATTERN.matcher(str);
        return matcher.matches();
    }

}

其中aes.key为加密key随便填

定义mybatis拦截器

MyBatisInterceptor.java

bash 复制代码

import cn.hutool.core.util.ReflectUtil;
import com.hw.common.annotation.SensitiveEntity;
import com.hw.common.service.AesService;
import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.binding.MapperMethod;
import org.apache.ibatis.executor.parameter.ParameterHandler;
import org.apache.ibatis.executor.resultset.ResultSetHandler;
import org.apache.ibatis.executor.statement.StatementHandler;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.plugin.*;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;

import javax.annotation.Resource;
import java.lang.reflect.Field;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Objects;
import java.util.Properties;

@Component
@Intercepts({
        @Signature(type = StatementHandler.class, method = "prepare", args = {Connection.class, Integer.class}),
        @Signature(type = ParameterHandler.class, method = "setParameters", args = PreparedStatement.class),
        @Signature(type = ResultSetHandler.class, method = "handleResultSets", args = {Statement.class})
})
@Slf4j
public class MyBatisInterceptor implements Interceptor {
    @Resource
    private AesService aesService;

    @Override
    public Object intercept(Invocation invocation) throws Throwable {
        Object target = invocation.getTarget();
        //拦截sql结果处理器
        if (target instanceof ResultSetHandler) {
            return resultDecrypt(invocation);
        }
        //拦截sql参数处理器
        if (target instanceof ParameterHandler) {
            return parameterEncrypt(invocation);
        }
        //拦截sql语句处理器
        if (target instanceof StatementHandler) {
            return replaceSql(invocation);
        }
        return invocation.proceed();
    }

    /**
     * 对mybatis映射结果进行字段解密
     *
     * @param invocation 参数
     * @return 结果
     * @throws Throwable 异常
     */
    private Object resultDecrypt(Invocation invocation) throws Throwable {
        //取出查询的结果
        Object resultObject = invocation.proceed();
        if (Objects.isNull(resultObject)) {
            return null;
        }
        //基于selectList
        if (resultObject instanceof ArrayList) {
            ArrayList resultList = (ArrayList) resultObject;
            if (CollectionUtils.isEmpty(resultList)) {
                return resultObject;
            }
            for (Object result : resultList) {
                if (needToDecrypt(result)) {
                    //逐一解密
                    aesService.decrypt(result);
                }
            }
            //基于selectOne
        } else {
            if (needToDecrypt(resultObject)) {
                aesService.decrypt(resultObject);
            }
        }
        return resultObject;
    }

    /**
     * mybatis映射参数进行加密
     *
     * @param invocation 参数
     * @return 结果
     * @throws Throwable 异常
     */
    private Object parameterEncrypt(Invocation invocation) throws Throwable {
        //@Signature 指定了 type= parameterHandler 后，这里的 invocation.getTarget() 便是parameterHandler
        //若指定ResultSetHandler ，这里则能强转为ResultSetHandler
        ParameterHandler parameterHandler = (ParameterHandler) invocation.getTarget();
        // 获取参数对像，即 mapper 中 paramsType 的实例
        Field parameterField = parameterHandler.getClass().getDeclaredField("parameterObject");
        parameterField.setAccessible(true);
        //取出实例
        Object parameterObject = parameterField.get(parameterHandler);

        if(parameterHandler.getParameterObject() instanceof MapperMethod.ParamMap){
            MapperMethod.ParamMap paramMap = (MapperMethod.ParamMap) parameterHandler.getParameterObject();
            parameterObject = paramMap.get("param1");
        }
        if (null == parameterObject) {
            return invocation.proceed();
        }
        Class<?> parameterObjectClass = parameterObject.getClass();
        //校验该实例的类是否被@SensitiveEntity所注解
        SensitiveEntity sensitiveEntity = AnnotationUtils.findAnnotation(parameterObjectClass, SensitiveEntity.class);
        //未被@SensitiveEntity所注解 则为null
        if (Objects.isNull(sensitiveEntity)) {
            return invocation.proceed();
        }
        //取出当前当前类所有字段，传入加密方法
        //Field[] declaredFields = parameterObjectClass.getDeclaredFields();
        Field[] allFields = ReflectUtil.getFields(parameterObjectClass);
        aesService.encrypt(allFields, parameterObject);
        return invocation.proceed();
    }

    /**
     * 替换mybatis Sql中的加密Key
     *
     * @param invocation 参数
     * @return 结果
     * @throws Throwable 异常
     */
    private Object replaceSql(Invocation invocation) throws Throwable {
        StatementHandler statementHandler = (StatementHandler) invocation.getTarget();
        BoundSql boundSql = statementHandler.getBoundSql();
        //获取到原始sql语句
        String sql = boundSql.getSql();
        if (null == sql){
            return invocation.proceed();
        }
        //通过反射修改sql语句
        Field field = boundSql.getClass().getDeclaredField("sql");
        field.setAccessible(true);
        field.set(boundSql, sql);
        return invocation.proceed();
    }

    /**
     * 判断是否包含需要加解密对象
     *
     * @param object 参数
     * @return 结果
     */
    private boolean needToDecrypt(Object object) {
        if(Objects.isNull(object)){
            return false;
        }
        Class<?> objectClass = object.getClass();
        Class<?> parentClass = objectClass.getSuperclass();
        SensitiveEntity sensitiveEntity = AnnotationUtils.findAnnotation(objectClass, SensitiveEntity.class);
        SensitiveEntity parentSensitiveEntity = AnnotationUtils.findAnnotation(parentClass, SensitiveEntity.class);

        return Objects.nonNull(sensitiveEntity) || Objects.nonNull(parentSensitiveEntity);
    }

    @Override
    public Object plugin(Object target) {
        return Plugin.wrap(target, this);
    }

    @Override
    public void setProperties(Properties properties) {

    }

}

总结

mybatis拦截器非常强大，它可以对所有存入数据库的数据进行处理，包括更新，插入，查询和删除...,对数据做统一处理非常方便。

注解方式实现数据库字段加密与解密

目录

前言

实现步骤

定义注解

加密工具类

定义mybatis拦截器

总结