Cas
Cas 6.x.x
Install Tomcat 9
apt-get install openjdk-11-jdk tomcat9
Copy certificates from proxy with rsync
Add the public key of the user that is going to copy the certificates to the /root directory. More details here http://docswiki.newro.co/index.php/SSHKeyAuth#Install_key_authentication_for_an_account. Create script /opt/bin/letsencrypt-sync.sh:
/usr/bin/rsync -rl --safe-links --rsync-path="/usr/bin/sudo /usr/bin/rsync" <user>@<proxy-ip>:/etc/letsencrypt/ /etc/letsencrypt-proxy/ 2>&1 >> /var/log/letsencrypt_sync.log openssl pkcs12 -export -in /etc/letsencrypt-proxy/live/<domain>/fullchain.pem -inkey /etc/letsencrypt-proxy/live/<domain>/privkey.pem -out /opt/bin/fullchain_and_key.p12 -name tomcat -password pass:<password> systemctl restart tomcat9
Make it executable
chmod +x /opt/bin/letsencrypt-sync.sh
Install rsync if not already
apt-get install rsync
Run the script for initial copy
/opt/bin/letsencrypt-sync.sh
Make the converted certificate readable for everyone
chmod +r /opt/bin/fullchain_and_key.p12
Create a crontab for automatic copy
vi /etc/cron.d/letsencrypt-sync
And add this to the file:
0 1 * * * root /opt/bin/letsencrypt-sync.sh
Configure Tomcat
Enable encryption by editing /etc/tomcat9/server.xml, uncomment and change appropriately the next section(change password with what you used in script above):
<Connector port="8443" protocol="org.apache.coyote.http11.Http11NioProtocol"
maxThreads="150" SSLEnabled="true" scheme="https" secure="true"
clientAuth="false" sslProtocol="TLS"
keystoreFile="/opt/bin/fullchain_and_key.p12" keystoreType="PKCS12"
keystorePass="<password>"
/>
In the same file, add/modify these lines at the end of the file to let tomcat see the original IP when running behind a reverse proxy
<Valve className="org.apache.catalina.valves.RemoteIpValve" />
<!-- Access log processes all example.
Documentation at: /docs/config/valve.html
Note: The pattern used is equivalent to using pattern="common" -->
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
prefix="localhost_access_log" suffix=".txt"
requestAttributesEnabled="true"
pattern="%h %l %u %t "%r" %s %b" />
Restart tomcat and you should be able to access it at https://my.domain.com:8443
systemctl restart tomcat9
Add the following argumet to the HTTPS proxy vhost:
SSLProxyEngine On
Install CAS
Download the CAS Overlay Template needed for installation.
mkdir /opt/cas cd /opt/cas wget https://github.com/apereo/cas-overlay-template/archive/6.1.zip unzip 6.1.zip cd cas-overlay-template-6.1
First, you need to open the file build.gradle and add the necessary dependencies. Here are the base dependencies that you'll most probably need:
dependencies {
compile "org.apereo.cas:cas-server-webapp${project.appServer}:${casServerVersion}"
compile "org.apereo.cas:cas-server-support-ldap:${casServerVersion}"
compile "com.unboundid:unboundid-ldapsdk:4.0.14"
compile "org.apereo.cas:cas-server-support-json-service-registry:${casServerVersion}"
}
For more dependencies like SAML, OAuth2, OpenID Connect, 2 Factor Authentication, etc. visit this page: https://apereo.github.io/cas/6.1.x/index.html
By default when building CAS, it doesn't make all the resources available, that you need to configure and customize your CAS instance. So you first need to make those resources available for the war file that you'll build.
./gradlew explodeWar mkdir src/main/resources cp -r build/cas-resources/* src/main/resources/
Note: if you are also building a failover server as well, or you think you'll need to rebuild the app in the future (e.g. to add another dependency) it will be easier to first configure CAS with the resources you just copied and then build it and copy the cas.war into the tomcat folder on all servers needed.
Now we can build the application war file.
./gradlew clean build
Move the resulted war file into the tomcat folder
cp build/libs/cas.war /var/lib/tomcat9/webapps/
Note: CAS 6.1 requires tomcat 9.0.27 (or newer), so if you have an older version of tomcat 9 it can still work but this will need to be set in /var/lib/tomcat9/webapps/cas/WEB-INF/classes/application.properties
spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.web.embedded.EmbeddedWebServerFactoryCustomizerAutoConfiguration
To be able to manage what services/apps are allowed to authenticate through CAS, you need to add this line to the configuration
cas.serviceRegistry.initFromJson=true cas.serviceRegistry.json.location=file:/var/lib/tomcat9/webapps/cas/WEB-INF/classes/services
If you plan to implement OAuth2 on CAS you should specifically configure the service URL
cas.server.name=https://cas.domain.com
cas.server.prefix=${cas.server.name}/cas
Uncomment these 2 lines from the configuration to disable the default account.
#cas.authn.accept.users=casuser::Mellon #cas.authn.accept.name=Static Credentials
To set an LDAP server as the user source use this configuration
cas.authn.ldap[0].providerClass=org.ldaptive.provider.unboundid.UnboundIDProvider
cas.authn.ldap[0].type=AUTHENTICATED
cas.authn.ldap[0].ldapUrl=ldaps://ldap.domain.com
cas.authn.ldap[0].useSsl=true
cas.authn.ldap[0].useStartTls=false
cas.authn.ldap[0].connectTimeout=5000
cas.authn.ldap[0].minPoolSize=0
cas.authn.ldap[0].baseDn=cn=Users,dc=<domain>,dc=local
cas.authn.ldap[0].searchFilter=sAMAccountName={user}
cas.authn.ldap[0].bindDn=cn=<bind-user>,cn=Users,dc=<domain>,dc=local
cas.authn.ldap[0].bindCredential=<password>
cas.authn.ldap[0].trustCertificates=file:/opt/samba-cert/samba-cert.pem
cas.authn.ldap[0].principalAttributeList=sAMAccountName,mail,displayName
Restart tomcat
systemctl restart tomcat9
Change login page design
Add a new logo
To add logo to the login page first copy the .png file /cas/WEB-INF/classes/static/images directory and change the file ownership to tomcat user:
sudo chown tomcat:tomcat logo.png
Add following line to /var/lib/tomcat9/webapps/cas/WEB-INF/classes/templates/fragments/header.html before or after the "svg" tag contained in a <a> tag:
<a href="https://newro.co/"><img src="/cas/images/newroco_logo.png" style="width: 375px;height: 55px;"/></a>
To remove the drop down menu, remove all the
"<div class="collapse navbar-collapse" id="navbarSupportedContent">"
class.
Change the head bar background color
Add following file to /cas/WEB-INF/classes/static/css/cas.css line 11755:
header > .navbar {
background-color: #a1b1b9;
color: #fff;
Change the "Reset password?" button
Edit the text message /cas/WEB-INF/classes/messages.properties line 27 and the redirect link from /cas/WEB-INF/classes/templates/fragments/pmlinks.html line 32.
OAuth2
To be able to use the OAuth2 you first need to add this to the dependencies before building CAS
compile "org.apereo.cas:cas-server-support-oauth-webflow:${project.'cas.version'}"
Now create a json file in /var/lib/tomcat9/webapps/cas/WEB-INF/classes/services/ to allow an app to authenticate with CAS using the OAuth2 protocol
{
"@class" : "org.apereo.cas.support.oauth.services.OAuthRegisteredService",
"clientId": "OAuth2AppToBeAllowed",
"clientSecret": "<secret>", ### can be generated with "openssl rand -base64 32"
"serviceId" : "^https://app.domain.com/path/to/OAuth2/endpoint",
"name" : "OAuth for my App",
"id" : 10000002, ### make sure this id is unique
"attributeReleasePolicy" : {
"@class" : "org.apereo.cas.services.ReturnAllowedAttributeReleasePolicy",
"allowedAttributes" : [ "java.util.ArrayList", [ "sAMAccountName", "mail", "displayName" ] ]
},
"bypassApprovalPrompt" : true, ### this is needed so the user won't be asked at every login if he wants to allow the App to use the info provided by CAS
"evaluationOrder" : 102
}
Troubleshooting
In case you need to see how the response from CAS looks like, here is how you can find out. First install jq
apt-get install jq
Request a token from CAS
curl https://cas.domain.com/cas/oauth2.0/token?grant_type=password'&'client_id=client'&'client_secret=secret'&'username=my.user'&'password=my-password | jq
Then request the info about the user with the received token
curl -k --user client:secret https://cas.domain.com/cas/oauth2.0/profile?access_token=AT-1-wiNsTgaHzXLUIyaaoFoip-znohWPihea
Enable debug mode
logging.level.org.apereo.cas=DEBUG
2 Factor Authentication (2FA)
Note: CAS calls 2 Factor Authentication (2FA) as Multifactor Authentication (MFA). Mainly because it is possible to set multiple 2FA options in a certain order (e.g. user/pass -> 2fa sms -> 2fa email -> successful login)
To be able to use email 2FA you first need to add this to the dependencies before building CAS
compile "org.apereo.cas:cas-server-support-simple-mfa:${project.'cas.version'}"
Next you need to install postfix
apt-get install postfix
Add these lines to the CAS config in /var/lib/tomcat9/webapps/cas/WEB-INF/classes/application.properties
cas.authn.mfa.globalProviderId=mfa-simple cas.authn.mfa.simple.name=Email MFA cas.authn.mfa.simple.order=1 cas.authn.mfa.simple.timeToKillInSeconds=180 cas.authn.mfa.simple.tokenLength=6 cas.authn.mfa.simple.mail.from=no-reply@my.domain.com cas.authn.mfa.simple.mail.text=This is your 2FA code for CAS authentication: %s cas.authn.mfa.simple.mail.subject=CAS 2FA Code cas.authn.mfa.simple.mail.validateAddresses=false cas.authn.mfa.simple.mail.html=false cas.authn.mfa.simple.mail.attributeName=mail spring.mail.host=localhost spring.mail.port=25 spring.mail.testConnection=true spring.mail.properties.mail.smtp.auth=false spring.mail.properties.mail.smtp.starttls.enable=false
SMS (Nexmo)
To be able to use SMS 2FA you first need to add this to the dependencies before building CAS
compile "org.apereo.cas:cas-server-support-simple-mfa:${project.'cas.version'}"
compile "org.apereo.cas:cas-server-support-sms-nexmo:${project.'cas.version'}"
Create an account on Nexmo (https://dashboard.nexmo.com/sign-up). After that create a new application, that should give you an api key and a secret.
Add these lines to the CAS config in /var/lib/tomcat9/webapps/cas/WEB-INF/classes/application.properties
cas.authn.ldap[0].principalAttributeList=mail,telephoneNumber #you probably have this already in your config just need to add the phone attribute cas.authn.mfa.globalProviderId=mfa-simple cas.authn.mfa.simple.name=SMS 2FA cas.authn.mfa.simple.order=1 cas.authn.mfa.simple.timeToKillInSeconds=180 cas.authn.mfa.simple.tokenLength=6 cas.authn.mfa.simple.sms.from=CAS cas.authn.mfa.simple.sms.text=This is your CAS 2FA code: %s cas.authn.mfa.simple.sms.attributeName=telephoneNumber cas.smsProvider.nexmo.apiToken=<api-key> cas.smsProvider.nexmo.apiSecret=<api-secret>
Cas 4.x-5.x (old)
Install Tomcat 8
apt-get install openjdk-8-jdk apt-get install tomcat8
Copy certificates from proxy with rsync
Add the public key of the user that is going to copy the certificates to the /root directory. More details here http://docswiki.newro.co/index.php/SSHKeyAuth#Install_key_authentication_for_an_account. Create script /opt/bin/letsencrypt_sync:
/usr/bin/rsync -rl --safe-links --rsync-path="/usr/bin/sudo /usr/bin/rsync" <user>@<proxy-ip>:/etc/letsencrypt/ /etc/letsencrypt-proxy/ 2>&1 >> /var/log/letsencrypt_sync.log openssl pkcs12 -export -in /etc/letsencrypt-proxy/live/<domain>/fullchain.pem -inkey /etc/letsencrypt-proxy/live/<domain>/privkey.pem -out /opt/bin/fullchain_and_key.p12 -name tomcat -password pass:<password> systemctl restart tomcat8
Make it executable
chmod +x /opt/bin/letsencrypt_sync
Install rsync if not already
apt-get install rsync
Run the script for initial copy
/opt/bin/letsencrypt_sync
Create a crontab for automatic copy
crontab -u root -e
And add this to the file:
0 0 * * * /opt/bin/letsencrypt_sync
Enable SSL
Edit /etc/tomcat8/server.xml, uncomment and change appropriately the next section(change password with what you used in script above):
<Connector port="8443" protocol="org.apache.coyote.http11.Http11NioProtocol"
maxThreads="150" SSLEnabled="true" scheme="https" secure="true"
clientAuth="false" sslProtocol="TLS"
keystoreFile="/opt/bin/fullchain_and_key.p12" keystoreType="PKCS12"
keystorePass="<password>"
/>
Restart tomcat (service tomcat8 restart) and you should be able to access it at https://server-ip:8443
Add the following argumet to the HTTPS proxy vhost:
SSLProxyEngine On
Install CAS
First we need to install maven.
apt-get install maven
Create a directory to download cas and in that directory create a file pom.xml. The content of pom.xml for the latest CAS version can be taken from https://github.com/apereo/cas-overlay-template/blob/master/pom.xml
mkdir ~/cas vi ~/cas/pom.xml
If you want CAS to use LDAP then add this to pom.xml inside <dependencies> tag:
<dependency>
<groupId>org.apereo.cas</groupId>
<artifactId>cas-server-support-ldap</artifactId>
<version>${cas.version}</version>
</dependency>
Now go to ~/cas directory, download CAS and copy cas.war to tomcats webapp folder.
cd ~/cas mvn clean package cp target/cas.war /var/lib/tomcat8/webapps/ service tomcat8 restart
The CAS login page can be found at https://server-ip:8443/cas/login
Configure CAS
If the samba/LDAP server is using a self-signed certificate copy it (from /var/lib/samba/private/tls/samba-cert.pem) to the CAS server in /opt/bin/samba-cert.pem. Create a samba user for CAS to use. Back on the CAS server, add a line in /etc/hosts:
samba-server-ip hostname.domain.local
Edit /var/lib/tomcat8/webapps/cas/WEB-INF/classes/application.properties file. Comment if you find a line like this:
cas.authn.accept.users=casuser::Mellon
And add this at the end of the file, changing it for your case:
cas.authn.ldap[0].type=AUTHENTICATED
cas.authn.ldap[0].ldapUrl=ldaps://hostname.domain.local
cas.authn.ldap[0].useSsl=true
cas.authn.ldap[0].connectTimeout=5000
cas.authn.ldap[0].baseDn=dc=DOMAIN,dc=LOCAL
cas.authn.ldap[0].userFilter=sAMAccountName={user}
cas.authn.ldap[0].subtreeSearch=true
cas.authn.ldap[0].usePasswordPolicy=true
cas.authn.ldap[0].bindDn=cn=cas-user,cn=Users,dc=DOMAIN,dc=LOCAL
cas.authn.ldap[0].bindCredential=cas-user-passwords
cas.authn.ldap[0].trustCertificates=file:/opt/bin/samba-cert.pem
Change this line at the beginning of /var/lib/tomcat8/webapps/cas/WEB-INF/classes/log4j2.xml
<Property name="baseDir">/etc/cas/logs</Property>
To
<Property name="baseDir">/var/lib/tomcat8/webapps/cas/WEB-INF/classes/logs</Property>
Add a cronjob to delete old logs.
#vi /etc/cron.daily/cas-old-logs #!/bin/bash find /var/lib/tomcat8/webapps/cas/WEB-INF/classes/logs -mtime +10 -type f -delete
Make it executable
chmod +x /etc/cron.daily/cas-old-logs
Restart tomcat
service tomcat8 restart
Note: tomcat8 and its apps take a long time to fully restart.
Tomcat logs
By default the logrotate created by tomcat rotates weekly and keeps 52 log files. You probably don't need that much, so to keep the disk to a low, change the rotation to daily and keep 30 files or whatever suits you.
#vi /etc/logrotate.d/tomcat8
/var/log/tomcat8/catalina.out {
copytruncate
daily
rotate 30
compress
missingok
create 640 tomcat8 adm
}
Service registry
By default CAS allows all services that come from HTTPS or IMAPS. If you want to change that you can modify /var/lib/tomcat8/webapps/cas/WEB-INF/classes/services/HTTPSandIMAPS-10000001.json or create a another file in the same folder with similar format.
If CAS says that the service is not authorized even if it is, add this line to /var/lib/tomcat8/webapps/cas/WEB-INF/classes/application.properties
cas.serviceRegistry.initFromJson=true
If your LDAP server is case insensitive but one of your services is case sensitive you might want to transform login usernames to lowercase, as LDAP would accept "User.Name" even it is actually "user.name", but your service will see User.Name as a new user.
To do this add the following to the json file from /var/lib/tomcat8/webapps/cas/WEB-INF/classes/services that defines the service
"usernameAttributeProvider": {
"@class": "org.apereo.cas.services.DefaultRegisteredServiceUsernameProvider",
"canonicalizationMode": "LOWER"
}
Ticket Experation
If you want to change the ticket expiration time you can add this to /var/lib/tomcat8/webapps/cas/WEB-INF/classes/application.properties
cas.ticket.tgt.timeout.maxTimeToLiveInSeconds=28800
Internal DNS records
If the CAS server and other web services that use CAS for authentication are behind the same proxy they will probably need internal DNS records pointing to the internal IP of the proxy to avoid loops in the firewall routing.
Failover
If you want to have a failover CAS build a second server exactly as above and configure a floating IP with Keepalived as below.
Keepalived
To setup keepalived, install it on both servers:
sudo apt-get install keepalived
Copy the nagios check "check_http" to /usr/local/bin, from the /usr/lib/nagios/plugins of a server that has nagios-plugins installed (please don't install nagios-plugins on the CAS servers, that package would install many dependencies).
Finally create the following /etc/keepalived/keepalived.conf on the master:
global_defs {
notification_email {
<email>
}
notification_email_from <email>
smtp_server 127.0.0.1
}
vrrp_script chk_apache {
script "check_http -S -H 127.0.0.1 -u /cas/ -p 8443"
interval 3 # check every 3 seconds
weight 2 # add 2 points of prio if OK
}
vrrp_instance floating_ip {
interface ens3
state MASTER
virtual_router_id 31
priority 101
authentication {
auth_type PASS
auth_pass justatestpass
}
virtual_ipaddress {
<floating-IP>
}
track_script {
chk_apache
}
}
Create exactly the same file on the failover CAS, just change priority from 101 to 100.
Restart keepalived
service keepalived restart
