实现Spring RESTful服务的SSL
Heartbleed 使得大家对SSL安全问题很重视，TSL是SSL演化的新名词，实际使用时推荐最新技术，本课程介绍如何让基于Spring的REST服务变得SSL/TSL化。本课程使用到下面的配置：
- TomEE (or Tomcat) 的 SSL配置
- Spring
- Apache HTTP组件
首先，假设一个Spring REST 服务如下：
@Controller
@RequestMapping("/")
public class RestService {
@RequestMapping(method = RequestMethod.GET)
@ResponseBody
public String get() {
return "Called the get Rest Service";
}
}
Web.xml的配置如下：
<?xml version="1.0" encoding="UTF-8"?>
<web-app
version="3.1"
xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd">
<servlet>
<servlet-name>rest</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextClass</param-name>
<param-value>org.springframework.web.context.support.AnnotationConfigWebApplicationContext</param-value>
</init-param>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>com.radcortez.rest.ssl</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>rest</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<security-constraint>
<web-resource-collection>
<web-resource-name>Rest Application</web-resource-name>
<url-pattern>/*</url-pattern>
</web-resource-collection>
<user-data-constraint>
<!-- Needed for our application to respond to https requests -->
<transport-guarantee>CONFIDENTIAL</transport-guarantee>
</user-data-constraint>
</security-constraint>
</web-app>
注意其中security-constraint, user-data-constraint 和 <transport-guarantee>CONFIDENTIAL</transport-guarantee>配置，这些指定这个应用需要一个安全连接。
运行这个服务，部署应用到TomEE，键入网址：https://localhost:8443/，如果你正常配置了tomcat的SSL配置，浏览https和端口844应该一切正常，返回：Called the Rest Service
如果现在调用客户端不是一般浏览器，而是一个Java客户端，这时会抛出错误：
Message: I/O error on GET request for "https://localhost:8443/":sun.security.validator.ValidatorException:
Exception: Caused by: javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
这是因为客户端JDK并没有你服务器的证书，你需要导入，这里我们展示使用编程方式提供信任蜜月的方式，这样做的好处：
- 你可以运行应用代码在多个环境(和JDK无关)
- 你不必每次手工将证书导入JDK
- 你也不必升级JDK时得记住你的证书
- 其他原因导致你不能直接向JDK导入证书
编写代码：
RestClientConfig.java
@Configuration
@PropertySource("classpath:config.properties")
public class RestClientConfig {
@Bean
public RestOperations restOperations(ClientHttpRequestFactory clientHttpRequestFactory) throws Exception {
return new RestTemplate(clientHttpRequestFactory);
}
@Bean
public ClientHttpRequestFactory clientHttpRequestFactory(HttpClient httpClient) {
return new HttpComponentsClientHttpRequestFactory(httpClient);
}
@Bean
public HttpClient httpClient(@Value("${keystore.file}") String file,
@Value("${keystore.pass}") String password) throws Exception {
KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType());
FileInputStream instream = new FileInputStream(new File(file));
try {
trustStore.load(instream, password.toCharArray());
} finally {
instream.close();
}
SSLContext sslcontext =
SSLContexts.custom().loadTrustMaterial(trustStore, new TrustSelfSignedStrategy()).build();
SSLConnectionSocketFactory sslsf =
new SSLConnectionSocketFactory(sslcontext, new String[]{"TLSv1.2"}, null,
BROWSER_COMPATIBLE_HOSTNAME_VERIFIER);
return HttpClients.custom().setSSLSocketFactory(sslsf).build();
}
@Bean
public static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer() {
return new PropertySourcesPlaceholderConfigurer();
}
}
这里我们使用Spring RestOperations接口规定一个RESTful操作的基本集合，下面我们使用Apache HTTP组件SSLConnectionSocketFactory 提供的功能来校验服务器的信任密钥，也是使用服务器的 KeyStore。
RestServiceClientIT.java
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = RestClientConfig.class)
public class RestServiceClientIT {
@Autowired
private RestOperations rest;
@Test
public void testRestRequest() throws Exception {
ResponseEntity response = rest.getForEntity("https://localhost:8443/", String.class);
System.out.println("response = " + response);
System.out.println("response.getBody() = " + response.getBody());
}
}
上面是一个简单的测试类，我们需要一个属性文件提供keystore文件位置和密码：
config.properties
keystore.file=${user.home}/.keystore
keystore.pass=changeit
现在我们可以运行测试客户端，你应该得到如下：
Response: <200 OK,Called the get Rest Service,{Server=[Apache-Coyote/1.1], Cache-Control=[private], Expires=[Thu, 01 Jan 1970 01:00:00 WET], Content-Type=, Content-Length=[27], Date=[Tue, 23 Dec 2014 01:29:20 GMT]}>
Body: Called the get Rest Service
这说明一切正常，现在，你可以使用Java客户端以SSL/TLS方式调用你的REST服务了。
本案例源码下载： REST SSL.