注解方式实现数据库字段加密与解密

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

import java.lang.annotation.*;@Target({ElementType.TYPE, ElementType.PARAMETER})
@Retention(RetentionPolicy.RUNTIME)
@Inherited
@Documented
public @interface SensitiveEntity {}

2、字段注解@SensitiveEntity

import java.lang.annotation.*;@Target({ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
@Inherited
@Documented
public @interface SensitiveField {}

加密工具类

AesFieldUtils.java

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

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 {@Resourceprivate AesService aesService;@Overridepublic 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selectListif (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ResultSetHandlerParameterHandler 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nullif (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);}@Overridepublic Object plugin(Object target) {return Plugin.wrap(target, this);}@Overridepublic 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。