使用Jasypt加密SpringBoot配置文件加密springboot配置文件

小試牛刀

1.構建一個springboot項目,並且引入jasypt依賴

<dependency>
        <groupId>com.github.ulisesbocchio</groupId>
        <artifactId>jasypt-spring-boot-starter</artifactId>
        <version>3.0.2</version>
</dependency>

2.編寫一個單元測試,用於獲取加密后的賬號密碼

StringEncryptor是jasypt-spring-boot-starter自動配置的加密工具，加密算法我們選擇PBEWithHmacSHA512AndAES_128，password為123abc

jasypt.encryptor.password=123abc
jasypt.encryptor.algorithm=PBEWithHmacSHA512AndAES_128

@SpringBootTest
class SpringbootPropertiesEncApplicationTests {

    @Autowired
    private StringEncryptor stringEncryptor;

    @Test
    void contextLoads() {
        String sunshujie = stringEncryptor.encrypt("sunshujie");
        String qwerty1234 = stringEncryptor.encrypt("qwerty1234");
        System.out.println(sunshujie);
        System.out.println(qwerty1234);
    }

}

3.在application.properties中配置加密后的賬號密碼

jasypt.encryptor.password=123abc
jasypt.encryptor.algorithm=PBEWithHmacSHA512AndAES_128
username=ENC(pXDnpH3GdMDBHdxraKyAt7IKCeX8mVlM9A9PeI9Ow2VUoBHRESQ5m8qhrbp45vH+)
password=ENC(qD55H3EKYpxp9cGBqpOfR2pqD/AgqT+IyClWKdW80MkHx5jXEViaJTAx6Es4/ZJt)

4.觀察在程序中是否能夠拿到解密后的賬號密碼

@SpringBootApplication
public class SpringbootPropertiesEncApplication implements CommandLineRunner {
    private static final Logger logger = LoggerFactory.getLogger(SpringbootPropertiesEncApplication.class);
    public static void main(String[] args) {
        SpringApplication.run(SpringbootPropertiesEncApplication.class, args);
    }

    @Value("${password}")
    private String password;
    @Value("${username}")
    private String username;

    @Override
    public void run(String... args) throws Exception {
        logger.info("username: {} , password: {} ", username, password);
    }
}

原理解析

加密原理

首先看jasypt相關的配置,分別是password和加密算法

jasypt.encryptor.password=123abc
jasypt.encryptor.algorithm=PBEWithHmacSHA512AndAES_128

PBEWithHmacSHA512AndAES_128是此次我們選用的加密算法.

123abc是PBEWithHmacSHA512AndAES_128加密過程中用的加密密碼.

PBE是基於密碼的加密算法,密碼和秘鑰相比有什么好處呢?好處就是好記…

PBE加密流程如下

1. 密碼加鹽

2. 密碼加鹽結果做摘要獲取秘鑰

3. 用秘鑰對稱加密原文,然后和鹽拼在一起得到密文

PBE解密流程如下

1. 從密文獲取鹽

2. 密碼+鹽摘要獲取秘鑰

3. 密文通過秘鑰解密獲取原文

再來看PBEWithHmacSHA512AndAES_128,名字就是加密過程中用的具體算法

• PBE是指用的是PBE加密算法

• HmacSHA512是指摘要算法,用於獲取秘鑰

• AES_128是對稱加密算法

jasypt-spring-boot-starter原理

先從spring.factories文件入手查看自動配置類

org.springframework.boot.autoconfigure.EnableAutoConfiguration=com.ulisesbocchio.jasyptspringboot.JasyptSpringBootAutoConfiguration

JasyptSpringBootAutoConfiguration配置僅僅使用@Import注解引入另一個配置類EnableEncryptablePropertiesConfiguration.

@Configuration
@Import({EnableEncryptablePropertiesConfiguration.class})
public class JasyptSpringBootAutoConfiguration {
    public JasyptSpringBootAutoConfiguration() {
    }
}

從配置類EnableEncryptablePropertiesConfiguration可以看到有兩個操作

1.@Import了EncryptablePropertyResolverConfiguration.class, CachingConfiguration.class

2.注冊了一個BeanFactoryPostProcessor -> EnableEncryptablePropertiesBeanFactoryPostProcessor

@Configuration
@Import({EncryptablePropertyResolverConfiguration.class, CachingConfiguration.class})
public class EnableEncryptablePropertiesConfiguration {
    private static final Logger log = LoggerFactory.getLogger(EnableEncryptablePropertiesConfiguration.class);

    public EnableEncryptablePropertiesConfiguration() {
    }

    @Bean
    public static EnableEncryptablePropertiesBeanFactoryPostProcessor enableEncryptablePropertySourcesPostProcessor(ConfigurableEnvironment environment) {
        boolean proxyPropertySources = (Boolean)environment.getProperty("jasypt.encryptor.proxy-property-sources", Boolean.TYPE, false);
        InterceptionMode interceptionMode = proxyPropertySources ? InterceptionMode.PROXY : InterceptionMode.WRAPPER;
        return new EnableEncryptablePropertiesBeanFactoryPostProcessor(environment, interceptionMode);
    }
}

先看EncryptablePropertyResolverConfiguration.class

lazyEncryptablePropertyDetector這里有配置文件中ENC()寫法的出處.從名稱來看是用來找到哪些配置需要解密.

從代碼來看,不一定非得用ENC()把密文包起來, 也可以通過配置來指定其他前綴和后綴

jasypt.encryptor.property.prefix
jasypt.encryptor.property.suffix
    @Bean(
        name = {"lazyEncryptablePropertyDetector"}
    )
    public EncryptablePropertyDetector encryptablePropertyDetector(EncryptablePropertyResolverConfiguration.EnvCopy envCopy, BeanFactory bf) {
        String prefix = envCopy.get().resolveRequiredPlaceholders("${jasypt.encryptor.property.prefix:ENC(}");
        String suffix = envCopy.get().resolveRequiredPlaceholders("${jasypt.encryptor.property.suffix:)}");
        String customDetectorBeanName = envCopy.get().resolveRequiredPlaceholders(DETECTOR_BEAN_PLACEHOLDER);
        boolean isCustom = envCopy.get().containsProperty("jasypt.encryptor.property.detector-bean");
        return new DefaultLazyPropertyDetector(prefix, suffix, customDetectorBeanName, isCustom, bf);
    }

另外還配置了很多bean,先記住這兩個重要的bean.帶着疑問往后看.

• lazyEncryptablePropertyResolver 加密屬性解析器

• lazyEncryptablePropertyFilter 加密屬性過濾器

  @Bean(
        name = {"lazyEncryptablePropertyResolver"}
    )
    public EncryptablePropertyResolver encryptablePropertyResolver(@Qualifier("lazyEncryptablePropertyDetector") EncryptablePropertyDetector propertyDetector, @Qualifier("lazyJasyptStringEncryptor") StringEncryptor encryptor, BeanFactory bf, EncryptablePropertyResolverConfiguration.EnvCopy envCopy, ConfigurableEnvironment environment) {
        String customResolverBeanName = envCopy.get().resolveRequiredPlaceholders(RESOLVER_BEAN_PLACEHOLDER);
        boolean isCustom = envCopy.get().containsProperty("jasypt.encryptor.property.resolver-bean");
        return new DefaultLazyPropertyResolver(propertyDetector, encryptor, customResolverBeanName, isCustom, bf, environment);
    }

    @Bean(
        name = {"lazyEncryptablePropertyFilter"}
    )
    public EncryptablePropertyFilter encryptablePropertyFilter(EncryptablePropertyResolverConfiguration.EnvCopy envCopy, ConfigurableBeanFactory bf, @Qualifier("configPropsSingleton") Singleton<JasyptEncryptorConfigurationProperties> configProps) {
        String customFilterBeanName = envCopy.get().resolveRequiredPlaceholders(FILTER_BEAN_PLACEHOLDER);
        boolean isCustom = envCopy.get().containsProperty("jasypt.encryptor.property.filter-bean");
        FilterConfigurationProperties filterConfig = ((JasyptEncryptorConfigurationProperties)configProps.get()).getProperty().getFilter();
        return new DefaultLazyPropertyFilter(filterConfig.getIncludeSources(), filterConfig.getExcludeSources(), filterConfig.getIncludeNames(), filterConfig.getExcludeNames(), customFilterBeanName, isCustom, bf);
    }

再看EnableEncryptablePropertiesBeanFactoryPostProcessor這個類

1. 是一個BeanFactoryPostProcessor

2. 實現了Ordered,是最低優先級,會在其他BeanFactoryPostProcessor執行之后再執行

3. postProcessBeanFactory方法中獲取了上面提到的兩個重要的bean, lazyEncryptablePropertyResolver lazyEncryptablePropertyFilter

4. 從environment中獲取了PropertySources

5. 調用工具類進行轉換PropertySources, 也就是把密文轉換為原文

public class EnableEncryptablePropertiesBeanFactoryPostProcessor implements BeanFactoryPostProcessor, Ordered {    
    // ignore some code
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        LOG.info("Post-processing PropertySource instances");
        EncryptablePropertyResolver propertyResolver = (EncryptablePropertyResolver)beanFactory.getBean("lazyEncryptablePropertyResolver", EncryptablePropertyResolver.class);
        EncryptablePropertyFilter propertyFilter = (EncryptablePropertyFilter)beanFactory.getBean("lazyEncryptablePropertyFilter", EncryptablePropertyFilter.class);
        MutablePropertySources propSources = this.environment.getPropertySources();
        EncryptablePropertySourceConverter.convertPropertySources(this.interceptionMode, propertyResolver, propertyFilter, propSources);
    }

    public int getOrder() {
        return 2147483547;
    }
}

再看工具類EncryptablePropertySourceConverter

1.過濾所有已經是EncryptablePropertySource的PropertySource

2.轉換為EncryptablePropertySource

3.用EncryptablePropertySource從PropertySources中替換原PropertySource

   public static void convertPropertySources(InterceptionMode interceptionMode, EncryptablePropertyResolver propertyResolver, EncryptablePropertyFilter propertyFilter, MutablePropertySources propSources) {
        ((List)StreamSupport.stream(propSources.spliterator(), false).filter((ps) -> {
            return !(ps instanceof EncryptablePropertySource);
        }).map((ps) -> {
            return makeEncryptable(interceptionMode, propertyResolver, propertyFilter, ps);
        }).collect(Collectors.toList())).forEach((ps) -> {
            propSources.replace(ps.getName(), ps);
        });
    }

關鍵方法在makeEncryptable中,調用鏈路很長, 這里選取一條鏈路跟一下

1. .ulisesbocchio.jasyptspringboot.EncryptablePropertySourceConverter#makeEncryptable

2. com.ulisesbocchio.jasyptspringboot.EncryptablePropertySourceConverter#convertPropertySource

3. com.ulisesbocchio.jasyptspringboot.EncryptablePropertySourceConverter#proxyPropertySource

4. com.ulisesbocchio.jasyptspringboot.aop.EncryptablePropertySourceMethodInterceptor#invoke

5. com.ulisesbocchio.jasyptspringboot.caching.CachingDelegateEncryptablePropertySource#getProperty

6. com.ulisesbocchio.jasyptspringboot.EncryptablePropertySource#getProperty()

看到最后豁然開朗,發現就是用的最開始配置的DefaultLazyPropertyResolver進行密文解析.

直接看最終的實現 DefaultPropertyResolver

1. 據lazyEncryptablePropertyDetector過濾需要解密的配置
2. 用lazyEncryptablePropertyDetector去掉前綴后綴
3. 替換占位符
4. 解密

 public String resolvePropertyValue(String value) {
        Optional var10000 = Optional.ofNullable(value);
        Environment var10001 = this.environment;
        var10001.getClass();
        var10000 = var10000.map(var10001::resolveRequiredPlaceholders);
        EncryptablePropertyDetector var2 = this.detector;
        var2.getClass();
        return (String)var10000.filter(var2::isEncrypted).map((resolvedValue) -> {
            try {
                String unwrappedProperty = this.detector.unwrapEncryptedValue(resolvedValue.trim());
                String resolvedProperty = this.environment.resolveRequiredPlaceholders(unwrappedProperty);
                return this.encryptor.decrypt(resolvedProperty);
            } catch (EncryptionOperationNotPossibleException var5) {
                throw new DecryptionException("Unable to decrypt: " + value + ". Decryption of Properties failed,  make sure encryption/decryption passwords match", var5);
            }
        }).orElse(value);
    }

解惑

1.加密配置文件能否使用摘要算法,例如md5?

不能, 配置文件加密是需要解密的,例如數據庫連接信息加密,如果不解密,springboot程序無法讀取到真正的數據庫連接信息,也就無法建立連接.

2.加密配置文件能否直接使用對稱加密,不用PBE?

可以, PBE的好處就是密碼好記.

3.jasypt.encryptor.password可以泄漏嗎?

不能, 泄漏了等於沒有加密.

4.例子中jasypt.encryptor.password配置在配置文件中不就等於泄漏了嗎?

是這樣的,需要在流程上進行控制.springboot打包時千萬不要把jasypt.encryptor.password打入jar包內.