The Shibboleth IdP V4 software has reached its End of Life and is no longer supported. This documentation is available for historical purposes only. See the IDP5 wiki space for current documentation on the supported version.
The "authn/X509Internal" login flow leverages any surrounding mechanism you have available for TLS client certificate authentication, provided the standard servlet request attribute ("javax.servlet.request.X509Certificate") is populated. By default, this flow is configured without support for advanced authentication controls like passive or forced authentication since this is not generally possible with client certificate authentication.
The difference between this flow and the X509 flow is that this flow doesn't redirect to a protected path; rather, the path of the requested profile flow has to be protected, which typically will trigger as soon as the client makes its first request. This is primarily suited to non-browser clients or other scenarios in which authentication is uniformly certificate-based.
The main disadvantage of using this flow for browser use cases is that it will perform the request for authentication without having a chance to determine if the request will succeed, which may be undesirable from a usability perspective.
The result of this flow is a Java Subject containing an X500Principal derived from the subject of the certificate, and the certificate is added as a public credential of the Subject. Note that no actual "username" is produced; rather, a suitable post-login Subject Canonicalization flow must be enabled/configured to pull a suitable principal name out of the Subject.
Note that if you have a web server that is configured to perform the certificate evaluation for you and populate a header or variable with the "username" to use based on the certificate, you almost certainly will want to use the RemoteUser or RemoteUserInternal flow. This flow pulls in the certificate as the primary result of the authentication and relies on downstream logic (often the x500 subject canonicalization flow) to get a username out of it.
General Configuration
There is no configuration required, but you may use conf/global.xml to define a Spring bean named shibboleth.authn.X509.TrustEngine as an OpenSAML TrustEngine that should be used to validate the client certificate chain. Of course, it's often simpler and more common to do this validation at the web server itself, although that's less flexible.
An example of a PKIX-based TrustEngine declaration follows. The bean ID is defined to allow the built-in flow to locate it.
Whether to save the certificate into the Subject's public credential set. Disable to reduce the size if not relying on the certificate for subject c14n.
The general properties configuring this flow via authn/authn.properties are:
Name
Default
Description
Name
Default
Description
idp.authn.X509Internal.order
1000
Flow priority relative to other enabled login flows (lower is "higher" in priority)
idp.authn.X509Internal.nonBrowserSupported
true
Whether the flow should handle non-browser request profiles (e.g., ECP)
To replace the internally defined flow descriptor bean, the following XML is required:
In older versions and upgraded systems, this list is defined in conf/authn/general-authn.xml. In V4.1+, no default version of the list is provided and it may simply be placed in conf/global.xml if needed.