CAS SSO & SLO

在前面我们介绍了CAS Server 以及CAS Management。还介绍了CAS 结合LDAP来进行验证。

众所周知，CAS 本身是一个SSO 与 SLO 框架，接下来我们就来记录一下如何使用CAS 来实现SSO 和 SLO.

SSO & SLO

环境介绍

前面的介绍中，我们已经实现了gitlab 集成CAS+ LDAP 来实现登录验证，接下来我们还是采用gitlab，再加上WordPress 的方式实现和模拟SSO 以及SLO。

整体的方案如下图所示。

在之前的文章中，我们介绍CAS 都是使用的目前的最新版本 6.4.0。截止笔者整理这篇教程的时候，CAS 6.4.0 还未正式发布。也正式因为如此，在实验过程遇到了很多无法解决的问题，查遍全网也没有找到原因以及对应的解决方案。

因此，我们将CAS 的版本降低，来满足我们的实验要求。CAS应该降低到哪一个版本，这里也没有很好的依据。最终是根据Wordpress 的CAS 插件支持的最高版本决定了。

因此最终的实验环境如下

WP-cassify (WordPress 的CAS插件。截止实验时，这个插件最高支持CAS 5.3.x，因此我们的CAS也选择在5.3.x)
CAS 5.3.x
Gitlab CE 13.8.2
openldap-2.4.44-20.el7.x86_64
JDK 8

安装包的准备

由于 CAS 的版本降低到了 5.3.x。所以需要重新构建cas.war,以及cas-management.war。

cas

clone 下来 cas-overlay-template。参照之前的介绍修改cas.properties 和 maven 的配置。

在pom.xml 中添加如下的依赖。这些依赖在使用过程中，都需要用到。

<dependency>
    <groupId>org.apereo.cas</groupId>
    <artifactId>cas-server-support-ldap</artifactId>
    <version>${cas.version}</version>
</dependency>
<dependency>
    <groupId>org.apereo.cas</groupId>
    <artifactId>cas-server-support-json-service-registry</artifactId>
    <version>${cas.version}</version>
</dependency>
<dependency>
    <groupId>org.apereo.cas</groupId>
    <artifactId>cas-server-webapp-config-security</artifactId>
    <version>${cas.version}</version>
</dependency>

然后构建出来 cas.war 文件。

cas-management

clone 下来 cas-management-overlay 项目。参照之前的介绍修改 management.properties 和maven 配置。

然后构建出来 cas-management.war 文件。

HTTPS

CAS 框架作为一个认证登录框架，安全是首位重要的。在实验过程中，可以使用http来进行。我们这里配置一下 HTTPS .

生成证书

生成证书的时候，需要注意要使用域名进行生成，使用ip生成的话，会有问题。

keytool -genkey -alias cas -keyalg RSA -keysize 2048 -validity 36500 -keystore /etc/cas/keys/the-cas-ssl-keystore


What is your first and last name?
What is the name of your organizational unit?
What is the name of your organization?
What is the name of your City or Locality?
What is the name of your State or Province?
What is the two-letter country code for this unit?
Is CN=cas.sugon.com, OU=sugon.com, O=sugon, L=qingdao, ST=shandong, C=zh correct?

启用生成的这个证书

# Export the certificate into a file
keytool -export -file /etc/cas/keys/cas.crt -keystore /etc/cas/keys/the-cas-ssl-keystore -alias cas

# Import the certificate into the global keystore
sudo keytool -import -file /etc/cas/keys/cas.crt -alias cas -keystore $JAVA_HOME/lib/security/cacerts

更新配置

CAS

CAS 5.3.x 版本的配置，与后来版本的配置有着巨大的差异。这里将所有的配置罗列下来，以备参考。

cas.server.name=https://10.0.41.74:8090
cas.server.prefix=${cas.server.name}/cas
logging.config=file:/etc/cas/config/log4j2.xml
server.port=8090
server.ssl.enabled=true
server.ssl.key-store=file:/etc/cas/keys/the-cas-ssl-keystore
server.ssl.key-store-password=changeit
server.ssl.key-password=changeit
server.ssl.key-alias=cas

spring.main.allow-bean-definition-overriding=true


# sso 配置
cas.sso.allowMissingServiceParameter=true
cas.sso.createSsoCookieOnRenewAuthn=true
cas.sso.proxyAuthnEnabled=true
cas.sso.renewAuthnEnabled=true

cas.tgc.crypto.enabled=true
cas.tgc.max-age=-1
cas.tgc.httpOnly=false
cas.tgc.secure=false
cas.tgc.pinToSession=true
cas.tgc.rememberMeMaxAge=P14D

cas.slo.disabled=false
cas.slo.asynchronous=true

cas.logout.followServiceRedirects=true
cas.logout.redirectParameter=service
cas.logout.confirmLogout=false
cas.logout.removeDescendantTickets=false

cas.serviceRegistry.initFromJson=true
cas.serviceRegistry.watcherEnabled=true
cas.serviceRegistry.json.location=file:/etc/cas/services

cas.authn.oauth.grants.resourceOwner.requireServiceHeader=true
cas.authn.oauth.userProfileViewType=NESTED
cas.authn.policy.any.try-all=false
cas.authn.policy.any.enabled=true

cas.ticket.tgt.rememberMe.enabled=true
cas.ticket.tgt.rememberMe.timeToKillInSeconds=1209600


# 开启debug 模式
logging.level.org.apereo.cas=DEBUG

# don't allow login of built-in users
cas.authn.accept.users=

## 下面这些key ，如果暂时没有生成，先不用填。启动过程中注意查看日志，会自动生成。

cas.tgc.crypto.signing.key=CIcpiVI97d57UmHhiYCSozo2QC8spO6pywdSofBrSJoLxnxWnuVdEYOfevUol9Cu-29GN6eF4RQN-Q8ayR0knQ
cas.tgc.crypto.signing.key-size=512

cas.tgc.crypto.encryption.key=xacTHFa9PP9dQPKH4MNiNP9BXoGU3HSsg665vZ_L3yE
cas.tgc.crypto.encryption.key-size=256
cas.tgc.crypto.alg=AES
cas.tgc.crypto.enabled=false

cas.authn.token.crypto.encryption.key=NIPZxwVwveB017VDuZTcZnR1MaCqscSaJmivFOA7d_c
cas.authn.token.crypto.signing.key=heX91m6vPc2Miu3iPD-HlOBqsA_LwQMKDlfPp0pLelPeRHmllJrrd99ThrltYcLZCQ05TC2OaPxSyE6HnsyqLw

cas.webflow.crypto.signing.key=oCFxNGwAcamNBDxNTdWAImA_ujdGXUTEedo8YDRp9iuiAb0spKxvSICRmbiGmCYWA-EbUkDaqXx-KaNJvaR18w
cas.webflow.crypto.encryption.key=mLgVHrGbp4jfj9Sp4_e9uQ

# ldap 的验证配置
ldap-dnformat=uid=%s,ou=People,dc=sugon,dc=com


cas.authn.ldap[0].ldap-url=ldap://10.0.41.74:389
cas.authn.ldap[0].bindDn=cn=ldapadm,dc=sugon,dc=com
cas.authn.ldap[0].bindCredential=root;123
cas.authn.ldap[0].baseDn=dc=sugon,dc=com
ldap-dnformat=uid=%s,ou=People,dc=sugon,dc=com

cas.authn.ldap[0].dnFormat=${ldap-dnformat}

cas.authn.ldap[0].searchFilter=(uid={user})
cas.authn.ldap[0].type=DIRECT
cas.authn.ldap[0].useSsl=false
cas.authn.ldap[0].useStartTls=false


# cas 的监控界面

cas.adminPagesSecurity.ip=.+
cas.monitor.endpoints.enabled=true
cas.monitor.endpoints.dashboard.enabled=true
cas.monitor.endpoints.discovery.enabled=true
cas.monitor.endpoints.auditEvents.enabled=true
cas.monitor.endpoints.authenticationEvents.enabled=true
cas.monitor.endpoints.configurationState.enabled=true
cas.monitor.endpoints.healthCheck.enabled=true
cas.monitor.endpoints.loggingConfig.enabled=true
cas.monitor.endpoints.metrics.enabled=true
cas.monitor.endpoints.attributeResolution.enabled=true
cas.monitor.endpoints.singleSignOnReport.enabled=true
cas.monitor.endpoints.statistics.enabled=true
cas.monitor.endpoints.trustedDevices.enabled=true
cas.monitor.endpoints.status.enabled=true
cas.monitor.endpoints.singleSignOnStatus.enabled=true
cas.monitor.endpoints.springWebflowReport.enabled=true
cas.monitor.endpoints.registeredServicesReport.enabled=true
cas.monitor.endpoints.configurationMetadata.enabled=true

cas.monitor.endpoints.sensitive=false
cas.monitor.endpoints.dashboard.sensitive=false
cas.monitor.endpoints.discovery.sensitive=false
cas.monitor.endpoints.auditEvents.sensitive=false
cas.monitor.endpoints.authenticationEvents.sensitive=false
cas.monitor.endpoints.configurationState.sensitive=false
cas.monitor.endpoints.healthCheck.sensitive=false
cas.monitor.endpoints.loggingConfig.sensitive=false
cas.monitor.endpoints.metrics.sensitive=false
cas.monitor.endpoints.attributeResolution.sensitive=false
cas.monitor.endpoints.singleSignOnReport.sensitive=false
cas.monitor.endpoints.statistics.sensitive=false
cas.monitor.endpoints.trustedDevices.sensitive=false
cas.monitor.endpoints.status.sensitive=false
cas.monitor.endpoints.singleSignOnStatus.sensitive=false
cas.monitor.endpoints.springWebflowReport.sensitive=false
cas.monitor.endpoints.registeredServicesReport.sensitive=false
cas.monitor.endpoints.configurationMetadata.sensitive=false

CAS Management

更新一下 cas-management的配置

cas.server.name=https://10.0.41.74:8090
cas.server.prefix=${cas.server.name}/cas
mgmt.serverName=http://10.0.41.74:8091
mgmt.adminRoles[0]=ROLE_ADMIN
mgmt.userPropertiesFile=file:/etc/cas/config/users.json
server.port=8091
logging.config=file:/etc/cas/config/log4j2-management.xml


cas.serviceRegistry.json.location=file:/etc/cas/services
mgmt.defaultLocale=zh

CAS Service

将 CAS Management， WordPress ， Gitlab的服务注册到 CAS 中。本次实验采用 JSON 存储，手动配置的方式来注册这些服务。

CasManagement-10000003.json

{
    "@class": "org.apereo.cas.services.RegexRegisteredService",
    "serviceId": "^http://10.0.41.74:8091/cas-management/.*",
    "name": "CasManagement",
    "id": 10000003,
    "description": "CAS Management sample service.",
    "evaluationOrder": 10000,
    "usernameAttributeProvider": {
        "@class": "org.apereo.cas.services.DefaultRegisteredServiceUsernameProvider"
    },
    "logoutType": "BACK_CHANNEL",
    "attributeReleasePolicy": {
        "@class": "org.apereo.cas.services.ReturnAllowedAttributeReleasePolicy",
        "principalAttributesRepository": {
            "@class": "org.apereo.cas.authentication.principal.DefaultPrincipalAttributesRepository"
        },
        "authorizedToReleaseCredentialPassword": true,
        "authorizedToReleaseProxyGrantingTicket": true
    },
    "singleSignOnParticipationPolicy": {
        "@class": "org.apereo.cas.services.DefaultRegisteredServiceSingleSignOnParticipationPolicy",
        "createCookieOnRenewedAuthentication": "TRUE"
    },
    "accessStrategy": {
        "@class": "org.apereo.cas.services.DefaultRegisteredServiceAccessStrategy",
        "enabled": true,
        "ssoEnabled": true
    }
}

Gitlab-10000004.json

{
  "@class": "org.apereo.cas.services.RegexRegisteredService",
  "serviceId": "^http://10.0.41.74/.*",
  "name": "Gitlab",
  "id": 10000004,
  "description": "Gitlab sample service",
  "singleSignOnParticipationPolicy": {
    "@class": "org.apereo.cas.services.DefaultRegisteredServiceSingleSignOnParticipationPolicy",
    "createCookieOnRenewedAuthentication": "TRUE"
  },
  "evaluationOrder": 20000,
  "usernameAttributeProvider": {
    "@class": "org.apereo.cas.services.DefaultRegisteredServiceUsernameProvider"
  },
  "logoutType": "BACK_CHANNEL",
  "attributeReleasePolicy": {
    "@class": "org.apereo.cas.services.ReturnAllowedAttributeReleasePolicy",
    "principalAttributesRepository": {
      "@class": "org.apereo.cas.authentication.principal.DefaultPrincipalAttributesRepository"
    },
    "authorizedToReleaseCredentialPassword": true,
    "authorizedToReleaseProxyGrantingTicket": true
  },
  "accessStrategy": {
    "@class": "org.apereo.cas.services.DefaultRegisteredServiceAccessStrategy",
    "unauthorizedRedirectUrl" : "http://10.0.41.74",
    "enabled": true,
    "ssoEnabled": true
  },
  "properties" : {
    "@class" : "java.util.HashMap",
    "skipRequiredServiceCheck" : {
      "@class" : "org.apereo.cas.services.DefaultRegisteredServiceProperty",
      "values" : [
        "java.util.HashSet",
        [
          "true" ] ]
    }
  }
}

Wordpress-10000005.json

{
    "@class": "org.apereo.cas.services.RegexRegisteredService",
    "serviceId": "^http://10.0.41.74:8002/wp-.*",
    "name": "Wordpress",
    "id": 10000005,
    "description": "Wordpress sample service.",
    "evaluationOrder": 10000,
    "usernameAttributeProvider": {
        "@class": "org.apereo.cas.services.DefaultRegisteredServiceUsernameProvider"
    },
    "logoutType": "BACK_CHANNEL",
    "logoutUrl":"http://10.0.41.74:8002/wp-login.php?loggedout=true&wp_lang=zh_CN",
    "attributeReleasePolicy": {
        "@class": "org.apereo.cas.services.ReturnAllowedAttributeReleasePolicy",
        "principalAttributesRepository": {
            "@class": "org.apereo.cas.authentication.principal.DefaultPrincipalAttributesRepository"
        },
        "authorizedToReleaseCredentialPassword": true,
        "authorizedToReleaseProxyGrantingTicket": true
    },
    "singleSignOnParticipationPolicy": {
        "@class": "org.apereo.cas.services.DefaultRegisteredServiceSingleSignOnParticipationPolicy",
        "createCookieOnRenewedAuthentication": "TRUE"
    },
    "accessStrategy": {
        "@class": "org.apereo.cas.services.DefaultRegisteredServiceAccessStrategy",
        "unauthorizedRedirectUrl" : "http://10.0.41.74:8002/",
        "enabled": true,
        "ssoEnabled": true
    },
"properties" : {
    "@class" : "java.util.HashMap",
    "skipRequiredServiceCheck" : {
      "@class" : "org.apereo.cas.services.DefaultRegisteredServiceProperty",
      "values" : [ "java.util.HashSet", [ "true" ] ]
    }
  }
}

NOTE:在后面服务正常启动后，可以在 /etc/cas/services-repo 目录下，看到这些服务被以json文件的形式存储在磁盘上。

WordPress

Wordpress 中关于CAS 的配置是基于 WP Cassify 插件来的。可以查看下面的一个截图。

gitlab

gitlab 的配置与之前没有什么大的不同。依然贴在下面供参考。

gitlab_rails['omniauth_enabled'] = true
gitlab_rails['omniauth_allow_single_sign_on'] = ['cas3']
gitlab_rails['omniauth_block_auto_created_users'] = false
gitlab_rails['omniauth_sync_email_from_provider'] = 'cas3'
gitlab_rails['omniauth_sync_profile_from_provider'] = ['cas3']
gitlab_rails['omniauth_sync_profile_attributes'] = ['email']
gitlab_rails['omniauth_auto_sign_in_with_provider'] = 'cas3'
gitlab_rails['omniauth_providers'] = [
  {
      "name"=> "cas3",
      "label"=> "cas",
      "args"=> {
          "url"=> 'https://10.0.41.74:8090',
          "ssl": true,
          "disable_ssl_verification": true,
          "login_url"=> '/cas/login',
          "service_validate_url"=> '/cas/p3/serviceValidate',
          "logout_url"=> '/cas/logout'
      }
  }
]

上面说的这些配置都更新好以后，就可以进行 SSO & SLO 测试了。

Actuator 界面

CAS 框架本身提供了可以用于管理SSO Session 以及查看服务运行状态的接口。在前面的配置中已经涵盖了，这里我们主要是贴一下截截图，仅供参考。

参考

提升

Service 注册尽量采用DB 来存储
管理界面要加上权限验证
集群部署
tomcat session 高可用

PreviousCAS 集成gitlab NextCAS Gitbook

Last updated 3 years ago