NIFI-9849 Refactor SAML Support with Spring Security 5

[exceptionfactory]

Summary

NIFI-9849 Refactors SAML 2.0 authentication support using Spring Security 5 libraries.

The spring-security-saml2-core library reached end of life in October 2021. Spring Security 5 introduced direct support for SAML 2.0 integration through the spring-security-saml2-service-provider library.

The refactored implementation replaces custom REST resources with Spring Security Filters and related components. The new Saml2AccessResource class has a single method for returning a Bearer Token previously set as cookie following successful SAML 2.0 authentication. The updated approach maintains support for existing SAML resource paths, and the Administrator's Guide includes an additional section for supported resources.

The new implementation retains support for existing SAML application properties, with the exception of the following removed properties:

1. nifi.security.user.saml.message.logging.enabled
2. nifi.security.user.saml.metadata.signing.enabled
3. nifi.security.user.saml.signature.digest.algorithm

The message.logging.enabled property is no longer applicable to the refactored implementation, and standard logger configuration applies to various Spring Security components.

The metadata.signing.enabled and signature.digest.algorithm properties applied signing SAML metadata and do not have analogous options in Spring Security 5.

The Spring Security 5 library supports both OpenSAML 3 and OpenSAML 4, however, OpenSAML 4 requires Java 11. Spring Security has marked OpenSAML 3 components as deprecated, and these implementations will need to be replaced with OpenSAML 4 components when Apache NiFi removes support for Java 8.

Tracking

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• Apache NiFi Jira issue created

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Build

• Build completed using mvn clean install -P contrib-check
  • JDK 8
  • JDK 11
  • JDK 17

Licensing

• New dependencies are compatible with the Apache License 2.0 according to the License Policy
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Documentation

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[thenatog]

Cool, will test this one out

[thenatog]

One thing I'm noticing is that the logout button isn't appearing in the top right corner after login. I am able to log in so far though using a Google SAML provider.

[exceptionfactory]

One thing I'm noticing is that the logout button isn't appearing in the top right corner after login.

Thanks for the feedback and highlighting the problem @thenatog. The /access/saml/login/exchange resource was conflicting with the SAML 2 filter responsible for consuming Asserting Party messages. As a result of the conflict, the web user interface did not retrieve the access token, which prevented the logout button from appearing.

Returning the entire token to the user interface is no longer necessary for the SAML authentication process, so I pushed an update that replaces the exchange method with a simpler approach that returns the Access Token Expiration, which is what the user interface uses to determine the visibility of the logout button.

[thenatog]

Confirmed that the logout button is now present, and I'm able to log in and out repeatedly without issue.

[bbende]

Nice work! I tested this in an environment that uses SAML with NiFi behind a reverse-proxy and was able to successfully authenticate to NiFi, everything worked as a drop-in replacement without needing to change anything in nifi.properties.

[thenatog]

+1 will merge