If you are not familiar with the oc command, refer to OpenShift - Getting Started with the oc command.

The oc get oauth command can be used to list the OAuth Identity Providers that have been created. If you are not familiar with OAuth, check out my article What is an OAuth token. By default, there is a single OAuth Identity Provider named cluster.

~]$ oc get oauth
NAME      AGE
cluster   373d

The oc describe oauth command can be used to display more details on the OAuth Identity Provider. In this example, the OAuth Identity Provider is using LDAP. OpenShift can be configured with the following identity providers.

• GitHub
• htpasswd (flat file with a users username and password)
• keystone
• kubeadmin (default administrator user ID)
• LDAP
• OpenID Connect

~]$ oc describe oauth cluster
Name:         cluster
Namespace:    
Labels:       <none>
Annotations:  release.openshift.io/create-only: true
API Version:  config.openshift.io/v1
Kind:         OAuth
Metadata:
  Creation Timestamp:  2021-07-16T17:10:50Z
  Generation:          21
  Managed Fields:
    API Version:  config.openshift.io/v1
    Fields Type:  FieldsV1
    fieldsV1:
      f:metadata:
        f:annotations:
          .:
          f:release.openshift.io/create-only:
      f:spec:
    Manager:      cluster-version-operator
    Operation:    Update
    Time:         2021-07-16T17:10:50Z
    API Version:  config.openshift.io/v1
    Fields Type:  FieldsV1
    fieldsV1:
      f:metadata:
        f:annotations:
          f:kubectl.kubernetes.io/last-applied-configuration:
      f:spec:
        f:identityProviders:
    Manager:         kubectl-client-side-apply
    Operation:       Update
    Time:            2021-10-20T12:36:44Z
  Resource Version:  104630825
  UID:               718713e8-e62f-45f0-a605-e04f84af99a0
Spec:
  Identity Providers:
    Ldap:
      Attributes:
        Email:
          mail
        Id:
          dn
        Name:
          cn
        Preferred Username:
          uid
      Bind DN:  cn=openshift_ldap,ou=Appmgmt,ou=svcs,O=acme
      Bind Password:
        Name:        ldap-secret
      Insecure:      true
      URL:           ldap://ldap.example.com/o=acme?cn?sub?(groupmembership=cn=Openshift_users,ou=OpenShift,ou=applications,ou=groups,o=Acme)
    Mapping Method:  claim
    Name:            acme-ldap
    Type:            LDAP
Events:              <none>

Or, the oc get oauth command with the --output json or --output yaml option can be used.

~]$ oc get oauth cluster --output yaml
apiVersion: config.openshift.io/v1
kind: OAuth
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"config.openshift.io/v1","kind":"OAuth","metadata":{"annotations":{},"name":"cluster"},"spec":{"identityProviders":[{"ldap":{"attributes":{"email":["mail"],"id":["dn"],"name":["cn"],"preferredUsername":["uid"]},"bindDN":"cn=openshift_ldap,ou=Appmgmt,ou=svcs,O=acme","bindPassword":{"name":"ldap-secret"},"insecure":true,"url":"ldap://ldap.example.com/o=acme?cn?sub?(groupmembership=cn=Openshift_users,ou=OpenShift,ou=applications,ou=groups,o=Acme)"},"mappingMethod":"claim","name":"acme-ldap","type":"LDAP"}]}}
    release.openshift.io/create-only: "true"
  creationTimestamp: "2021-07-16T17:10:50Z"
  generation: 21
  name: cluster
  resourceVersion: "104630825"
  uid: 718713e8-e62f-45f0-a605-e04f84af99a0
spec:
  identityProviders:
  - ldap:
      attributes:
        email:
        - mail
        id:
        - dn
        name:
        - cn
        preferredUsername:
        - uid
      bindDN: cn=openshift_ldap,ou=Appmgmt,ou=svcs,O=acme
      bindPassword:
        name: ldap-secret
      insecure: true
      url: ldap://ldap.example.com/o=acme?cn?sub?(groupmembership=cn=Openshift_users,ou=OpenShift,ou=applications,ou=groups,o=Acme)
    mappingMethod: claim
    name: acme-ldap
    type: LDAP

The openshift-authentication amespace should contain a config map that contains the enabled authentication methods.

~]$ oc get configmaps --namespace openshift-authentication
NAME                                   DATA   AGE
kube-root-ca.crt                       1      161d
openshift-service-ca.crt               1      161d
v4-0-config-system-cliconfig           1      355d
v4-0-config-system-metadata            1      355d
v4-0-config-system-service-ca          1      355d
v4-0-config-system-trusted-ca-bundle   1      355d

In this example, the config map named v4-0-config-system-cliconfig in the openshift-authentication namespace contains an LDAP identity provider

~]$ oc get configmap v4-0-config-system-cliconfig --namespace openshift-authentication --output json
        "identityProviders": [
            {
                "challenge": true,
                "login": true,
                "mappingMethod": "claim",
                "name": "acme-ldap",
                "provider": {
                    "apiVersion": "osin.config.openshift.io/v1",
                    "attributes": {
                        "email": [
                            "mail"
                        ],
                        "id": [
                            "dn"
                        ],
                        "name": [
                            "cn"
                        ],
                        "preferredUsername": [
                            "uid"
                        ]
                    },
                    "bindDN": "cn=openshift_ldap,ou=Appmgmt,ou=svcs,O=acme",
                    "bindPassword": {
                        "env": "",
                        "file": "/var/config/user/idp/0/secret/v4-0-config-user-idp-0-bind-password/bindPassword",
                        "keyFile": "",
                        "value": ""
                    },
                    "ca": "",
                    "insecure": true,
                    "kind": "LDAPPasswordIdentityProvider",
                    "url": "ldap://ldap.example.com/o=acme?cn?sub?(groupmembership=cn=Openshift_users,ou=OpenShift,ou=applications,ou=groups,o=Acme)"
                }
            }
        ],