Authentication to docker registry using server certificate

Problem: We have an internal docker registry to which I have created a login account using our server certificate. The user name was taken from: openssl x509 -in server.cert -subject -nameopt RFC2253 -noout. So, in the repository discover window, I set the username to “,OU=myorg-unit,O=myorg,C=US”, but I don’t have a password. I’m supposed to use the cert and key for authentication. How do I enter that?

Expected outcome:

Foreman and Proxy versions: foreman 3.0.1, katello 4.2.1

Foreman and Proxy plugin versions:

Distribution and version: CentOS 7.9

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