RADIUS Authentication
Guacamole supports delegating authentication to a RADIUS service, such as FreeRADIUS, to validate username and password combinations, and to support multi-factor authentication. This authentication method must be layered on top of some other authentication extension, such as those available from the main project website, in order to provide access to actual connections.
Downloading the RADIUS authentication extension
The RADIUS extension depends on software that is covered by a LGPL license, which is incompatible with the Apache 2.0 license under which Guacamole is licensed. Due to this dependency, the Guacamole project cannot distribute binary versions of the RADIUS extension. If you want to use this extension you will need to build the code - or at least the RADIUS extension yourself. Build instructions can be found in the section Installing Guacamole natively.
Installing RADIUS authentication
The RADIUS extension must be explicitly enabled during build time in order to
generate the binaries and resulting JAR file. This is done by adding the flag
-Plgpl-extensions to the Maven command line during the build, and should
result in the output below:
$ mvn clean package -Plgpl-extensions
[INFO] Scanning for projects...
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Build Order:
[INFO]
[INFO] guacamole-client [pom]
[INFO] guacamole-common [jar]
[INFO] guacamole-ext [jar]
[INFO] guacamole-common-js [pom]
[INFO] guacamole [war]
[INFO] extensions [pom]
[INFO] guacamole-auth-duo [jar]
[INFO] guacamole-auth-header [jar]
[INFO] guacamole-auth-jdbc [pom]
[INFO] guacamole-auth-jdbc-base [jar]
[INFO] guacamole-auth-jdbc-mysql [jar]
[INFO] guacamole-auth-jdbc-postgresql [jar]
[INFO] guacamole-auth-jdbc-sqlserver [jar]
[INFO] guacamole-auth-jdbc-dist [pom]
[INFO] guacamole-auth-json [jar]
[INFO] guacamole-auth-ldap [jar]
[INFO] guacamole-auth-quickconnect [jar]
[INFO] guacamole-auth-sso [pom]
[INFO] guacamole-auth-sso-base [jar]
[INFO] guacamole-auth-sso-cas [jar]
[INFO] guacamole-auth-sso-openid [jar]
[INFO] guacamole-auth-sso-saml [jar]
[INFO] guacamole-auth-sso-dist [pom]
[INFO] guacamole-auth-totp [jar]
[INFO] guacamole-history-recording-storage [jar]
[INFO] guacamole-vault [pom]
[INFO] guacamole-vault-base [jar]
[INFO] guacamole-vault-ksm [jar]
[INFO] guacamole-vault-dist [pom]
[INFO] guacamole-auth-radius [jar]
[INFO] guacamole-example [war]
[INFO] guacamole-playback-example [war]
...
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary for guacamole-client 1.5.5:
[INFO]
[INFO] guacamole-client ................................... SUCCESS [ 12.839 s]
[INFO] guacamole-common ................................... SUCCESS [ 15.446 s]
[INFO] guacamole-ext ...................................... SUCCESS [ 19.988 s]
[INFO] guacamole-common-js ................................ SUCCESS [ 22.000 s]
[INFO] guacamole .......................................... SUCCESS [01:08 min]
[INFO] extensions ......................................... SUCCESS [ 0.451 s]
[INFO] guacamole-auth-duo ................................. SUCCESS [ 7.043 s]
[INFO] guacamole-auth-header .............................. SUCCESS [ 4.836 s]
[INFO] guacamole-auth-jdbc ................................ SUCCESS [ 0.244 s]
[INFO] guacamole-auth-jdbc-base ........................... SUCCESS [ 8.011 s]
[INFO] guacamole-auth-jdbc-mysql .......................... SUCCESS [ 4.717 s]
[INFO] guacamole-auth-jdbc-postgresql ..................... SUCCESS [ 5.098 s]
[INFO] guacamole-auth-jdbc-sqlserver ...................... SUCCESS [ 5.620 s]
[INFO] guacamole-auth-jdbc-dist ........................... SUCCESS [ 4.031 s]
[INFO] guacamole-auth-json ................................ SUCCESS [ 6.319 s]
[INFO] guacamole-auth-ldap ................................ SUCCESS [ 8.948 s]
[INFO] guacamole-auth-quickconnect ........................ SUCCESS [ 9.128 s]
[INFO] guacamole-auth-sso ................................. SUCCESS [ 0.270 s]
[INFO] guacamole-auth-sso-base ............................ SUCCESS [ 3.665 s]
[INFO] guacamole-auth-sso-cas ............................. SUCCESS [ 12.263 s]
[INFO] guacamole-auth-sso-openid .......................... SUCCESS [ 5.667 s]
[INFO] guacamole-auth-sso-saml ............................ SUCCESS [ 5.068 s]
[INFO] guacamole-auth-sso-dist ............................ SUCCESS [ 4.884 s]
[INFO] guacamole-auth-totp ................................ SUCCESS [ 9.310 s]
[INFO] guacamole-history-recording-storage ................ SUCCESS [ 3.131 s]
[INFO] guacamole-vault .................................... SUCCESS [ 0.231 s]
[INFO] guacamole-vault-base ............................... SUCCESS [ 4.671 s]
[INFO] guacamole-vault-ksm ................................ SUCCESS [ 6.411 s]
[INFO] guacamole-vault-dist ............................... SUCCESS [ 3.421 s]
[INFO] guacamole-auth-radius .............................. SUCCESS [ 10.806 s]
[INFO] guacamole-example .................................. SUCCESS [ 2.052 s]
[INFO] guacamole-playback-example ......................... SUCCESS [ 0.938 s]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 04:36 min
[INFO] Finished at: 2023-01-10T17:27:11-08:00
[INFO] ------------------------------------------------------------------------
$
After the build completes successfully, the extension will be in the
extensions/guacamole-auth-radius/target/ directory, and will be called
guacamole-auth-radius-1.5.5.jar. This extension file can be copied to the
GUACAMOLE_HOME/extensions directory. If you are unsure where
GUACAMOLE_HOME is located on your system, please consult
Configuring Guacamole before proceeding.
Extensions are loaded in alphabetical order, and authentication is performed in the order in which the extensions were loaded. If you are stacking the RADIUS extension with another extension, like the JDBC extension, in order to store connection information, you may need to change the name of the RADIUS extension such that it is evaluated prior to the JDBC extension - otherwise an authentication failure in one of the previous modules may block the RADIUS module from ever being evaluated.
To install the RADIUS authentication extension, you must:
Create the
GUACAMOLE_HOME/extensionsdirectory, if it does not already exist.Copy
guacamole-auth-radius-1.5.5.jarintoGUACAMOLE_HOME/extensions.Configure Guacamole to use RADIUS authentication, as described below.
Configuring Guacamole for RADIUS authentication
This extension provides several configuration properties in order to
communicate properly with the RADIUS server to which it needs to authenticate.
It is important that you know several key pieces of information about the
RADIUS server - at a minimum, the server name or IP, the authentication port,
the authentication protocol in use by the server, and the shared secret for the
RADIUS client. If you are responsible for the RADIUS server, you’ll need to
properly configure these items to get Guacamole to authenticate properly. If
you’re not responsible for the RADIUS server you will need to work with the
administrator to get all of the necessary configuration items for the server.
These items will need to be configured in the
guacamole.properties file.
radius-hostnameThe RADIUS server to authenticate against. If not specified, localhost will be used.
radius-auth-portThe RADIUS authentication port on which the RADIUS service is is listening. If not specified, the default of 1812 will be used.
radius-shared-secretThe shared secret to use when talking to the RADIUS server. This parameter is required and the extension will not load if this is not specified.
radius-auth-protocolThe authentication protocol to use when talking to the RADIUS server. This parameter is required for the extension to operate. Supported values are: pap, chap, mschapv1, mschapv2, eap-md5, eap-tls, and eap-ttls. Support for PEAP is implemented inside the extension, but, due to a regression in the JRadius implementation, it is currently broken. Also, if you specify eap-ttls you will also need to specify the
radius-eap-ttls-inner-protocolparameter in order to properly configure the protocol used inside the EAP TTLS tunnel.radius-key-fileThe combination certificate and private key pair to use for TLS-based RADIUS protocols that require a client-side certificate. This parameter should specify the absolute path to the file. By default the extension will look for a file called
radius.keyin theGUACAMOLE_HOMEdirectory.radius-key-typeThe file type of the keystore specified by the
radius-key-fileparameter. Valid keystore types are pem, jceks, jks, and pkcs12. If not specified, this defaults to pkcs12, the default used by the JRadius library.radius-key-passwordThe password of the private key specified in the
radius-key-fileparameter. By default the extension will not use any password when trying to open the key file.radius-ca-fileThe absolute path to the file that stores the certificate authority certificates for encrypted connections to the RADIUS server. By default a file with the name ca.crt in the
GUACAMOLE_HOMEdirectory will be used.radius-ca-typeThe file type of keystore used for the certificate authority. Valid formats are pem, jceks, jks, and pkcs12. If not specified this defaults to pem.
radius-ca-passwordThe password used to protect the certificate authority store, if any. If unspecified the extension will attempt to read the CA store without any password.
radius-trust-allThis parameter controls whether or not the RADIUS extension should trust all certificates or verify them against known good certificate authorities. Set to true to allow the RADIUS server to connect without validating certificates. The default is false, which causes certificates to be validated.
radius-retriesThe number of times the client will retry the connection to the RADIUS server and not receive a response before giving up. By default the client will try the connection at most 5 times.
radius-timeoutThe timeout for a RADIUS connection in seconds. By default the client will wait for a response from the server for at most 60 seconds.
radius-eap-ttls-inner-protocolWhen EAP-TTLS is used, this parameter specifies the inner (tunneled) protocol to use talking to the RADIUS server. It is required when the
radius-auth-protocolparameter is set to eap-ttls. If theradius-auth-protocolvalue is set to something other than eap-ttls, this parameter has no effect and will be ignored. Valid options for this are any of the values forradius-auth-protocol, except for eap-ttls.radius-nas-ipThis property allows the server administrator to manually set an IP address that will be sent to the RADIUS server to identify this RADIUS client, known as the “Network Access Server” (NAS) IP address. When this property is not specified, the RADIUS extension attempts to automatically determine the IP address of the system on which Guacamole is running and uses that value.
Completing the installation
Guacamole will only reread guacamole.properties and load newly-installed
extensions during startup, so your servlet container will need to be restarted
before HTTP header authentication can be used. Doing this will disconnect all
active users, so be sure that it is safe to do so prior to attempting
installation. When ready, restart your servlet container and give the new
authentication a try.