对接OKTA 使用SAML2.0协议

对接OKTA 使用SAML2.0协议

缘起

给客户做项目，客户要求内部使用okta登陆，使用SAML2.0协议，需要对接。

okta初探

OKTA是SSO，有个网站可以让我们测试，地址：okta developer，SAML协议的交互流程大致如下

1. 浏览器打开需要登录系统登陆界面，系统登陆界面只有一个登陆按钮，没有输入用户名密码的地方（原因是OKTA使用域账户登陆的时候，能直接获取域账户名，除了这个还有好多客户端都支持，比如Apple账户）

2. 点击按钮，跳转到OKTA页面，这个页面只有一个loading动画，个人猜测里面有获取当前域账户名的代码

3. 然后再次一个跳转，这个跳转跳到一个回调url，这个url官方名称为Single Sign On URL，记住它，后面会用到。跳转到这个页面后，浏览器会发送一个POST请求，content-type是application/x-www-form-urlencoded，参数包含一个SAMLResponse和RelayState（这个是在OKTA控制台配置的回传参数）大概的样子是
   

4. 第3步中的SAMLResponse就是一个xml文档的base64编码后的数据，回调地址接收到SAMLResponse进行校验，并获取登陆名

OKTA的配置

1. Single Sign On URL配置我们的系统的地址，是OKTA将认证完成后告诉我们结果的一个接口，接收参数是SAMLResponse和RelayState，格式是application/x-www-form-urlencoded，java中方法签名大概是：

@RequestMapping(value = "/login/success",method = {RequestMethod.POST})
    public String loginSuccess(String SAMLResponse, String RelayState){

        System.out.println("sAMLResponse:"+SAMLResponse);
        System.out.println("RelayState:" + RelayState);

        return "success";
    }

配置的地方如下：

2. 全部配置完后会得到一个页面大致如下

注意：Identity Provider Single Sign-On URL这个就是上面第一步中点击按钮跳转到的链接X.509 Certificate这部分是公钥，用来验证SAMLResponse中签名的公钥
3. 这个页面可以让你上传一个csv文件（包含登陆名信息）加入到你的group里面，登陆是否能成功，就是取你的域账户名，查询是否在你的group里面，当然你可以配置更复杂的规则

验证逻辑

1. 引入jar包：

	<dependency>
		<groupId>org.opensamlgroupId>
		<artifactId>opensamlartifactId>
		<version>2.6.4version>
	dependency>

2. 验证逻辑：

import org.joda.time.DateTime;
import org.joda.time.DateTimeZone;
import org.opensaml.Configuration;
import org.opensaml.DefaultBootstrap;
import org.opensaml.saml2.core.Assertion;
import org.opensaml.saml2.core.Response;
import org.opensaml.xml.ConfigurationException;
import org.opensaml.xml.XMLObject;
import org.opensaml.xml.io.Unmarshaller;
import org.opensaml.xml.io.UnmarshallerFactory;
import org.opensaml.xml.io.UnmarshallingException;
import org.opensaml.xml.security.x509.BasicX509Credential;
import org.opensaml.xml.signature.Signature;
import org.opensaml.xml.signature.SignatureValidator;
import org.opensaml.xml.util.Base64;
import org.opensaml.xml.validation.ValidationException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.xml.sax.SAXException;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.security.KeyFactory;
import java.security.NoSuchAlgorithmException;
import java.security.PublicKey;
import java.security.cert.CertificateException;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.X509EncodedKeySpec;

public class Test {


    private static final Logger logger = LoggerFactory.getLogger(Test.class);
    private static final String pattern = "yyyy-MM-dd HH:mm:ss";
    private static final BasicX509Credential credential = new BasicX509Credential();
    //X.509 Certificate
    public static final String publicKeyStr = "xxxxxxx";
	//responseMsg就是SAMLResponse
    public String validate(String responseMsg) {


        ByteArrayInputStream byteArrayInputStream = null;
        try {
            CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509");
            byteArrayInputStream = new ByteArrayInputStream(Base64.decode(publicKeyStr));
            X509Certificate certificate = (X509Certificate) certificateFactory.generateCertificate(byteArrayInputStream);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(certificate.getPublicKey().getEncoded());
            PublicKey publicKey = keyFactory.generatePublic(publicKeySpec);
            credential.setPublicKey(publicKey);
        } catch (CertificateException e) {

            logger.error("加载okta PublicKey失败", e);
        } catch (NoSuchAlgorithmException e) {

            logger.error("加载okta PublicKey失败", e);
        } catch (InvalidKeySpecException e) {

            logger.error("加载okta PublicKey失败", e);
        }finally {
            if(byteArrayInputStream != null){
                try {
                    byteArrayInputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

        try (ByteArrayInputStream inputStream = new ByteArrayInputStream(Base64.decode(responseMsg))) {
            DefaultBootstrap.bootstrap();
            DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
            documentBuilderFactory.setNamespaceAware(true);
            DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
            Document document = documentBuilder.parse(inputStream);
            Element documentElement = document.getDocumentElement();
            UnmarshallerFactory unmarshallerFactory = Configuration.getUnmarshallerFactory();
            Unmarshaller unmarshaller = unmarshallerFactory.getUnmarshaller(documentElement);
            XMLObject xmlObject = unmarshaller.unmarshall(documentElement);
            Response response = (Response) xmlObject;
            Assertion assertion = response.getAssertions().get(0);
            //验证签名
            Signature signature = assertion.getSignature();
            SignatureValidator signatureValidator = new SignatureValidator(credential);
            //签名验证失败会抛错
            signatureValidator.validate(signature);
            //校验是否登录成功
            String successStr = response.getStatus().getStatusCode().getValue();
            if (!successStr.contains("Success")) {
                logger.error("登录成功标志校验失败，successStr={}", response.getStatus().getStatusCode().getValue());
                return null;
            }
            //检验登录时间
            DateTime notBefore = assertion.getConditions().getNotBefore();
            DateTime notOnOrAfter = assertion.getConditions().getNotOnOrAfter();
            DateTime now = new DateTime(DateTimeZone.UTC);
            logger.error("验证okta返回的时间，notBefore={},notOnOrAfter={},now={}",
                    notBefore.toString(pattern), notOnOrAfter.toString(pattern), now.toString(pattern));
            if (now.isBefore(notBefore) || now.isAfter(notOnOrAfter)) {
                logger.error("登录成功时间校验失败，notBefore={},notOnOrAfter={},now={}",
                        notBefore.toString(pattern), notOnOrAfter.toString(pattern), now.toString(pattern));
                return null;
            }
            //返回登录用户名
            return assertion.getSubject().getNameID().getValue();

        } catch (IOException e) {
            logger.error("验证SAMLResponse失败", e);
        } catch (ParserConfigurationException e) {
            logger.error("验证SAMLResponse失败", e);
        } catch (SAXException e) {
            logger.error("验证SAMLResponse失败", e);
        } catch (UnmarshallingException e) {
            logger.error("验证SAMLResponse失败", e);
        } catch (ValidationException e) {
            logger.error("验证SAMLResponse失败", e);
        } catch (ConfigurationException e) {
            logger.error("验证SAMLResponse失败", e);
        } catch (Exception ex) {
            logger.error("验证SAMLResponse失败", ex);
        }

        return null;
    }
}