After I got Keycloak wired up, logging into the dashboard started getting stuck. No error, no crash log. Just one of those situations where you feel like you’re missing something obvious and can’t see it. Today I tried again, and this time there was a clear error in the log: Invalid parameter: redirect_uri
My Home Lab Originally Only Used LLDAP For User Authentication, But Since The Systems I Wanted To Integrate Later Only Spoke OIDC, I Put Keycloak In Front Of It As A Bridge, With Everything Else Talking To Keycloak Instead. Wiring That Up And Testing It Turned Up Something Interesting: Got The LDAP Federation Wired Up, Got The OIDC Client Configured, Got Kubernetes Itself Trusting The Issuer. Then, Testing Whether Any Of It Actually Enforced Anything, I Ran One kubectl Command With A Made-Up Token String, And Got Back A Full Pod List. For About Thirty Seconds I Was Convinced I’d Found A Cluster-Wide Auth Bypass.
I Hadn’t. The Bug Was In My Test, Not My Cluster.