Spring Security KeyInfo missing in AuthnRequest when using OpenSaml4AuthenticationRequestResolver

Describe the bug When switching from the (deprecated) DefaultSaml2AuthenticationRequestContextResolver and OpenSaml4AuthenticationRequestFactory to OpenSaml4AuthenticationRequestResolver, the AuthnRequest's signature no longer contains a KeyInfo element.

To Reproduce - configure an OpenSaml4AuthenticationRequestResolver (e.g. by adding it as a Spring Bean) - configure an X.509 signing credential - start a SAML authentication

Expected behavior The AuthnRequest signature contains a KeyInfo when using OpenSaml4AuthenticationRequestResolver.

Possible source: In org.springframework.security.saml2.provider.service.web.authentication.OpenSamlSigningUtils, no NamedKeyInfoGeneratorManager is configured in the SignatureSigningConfiguration. This is different from the two OpenSamlSigningUtils in other packages.

Comment From: jzheaux

Thanks, @chschu, for the report. We will prioritize getting this into the next point release.