implement OIDC auth

config.yml

@@ -60,7 +60,7 @@ ssh.keygen-executable: ssh-keygen
 
 
 # OAuth2 configuration
-# The callback/redirect URL must be http://opengist.domain/oauth/<github|gitea>/callback
+# The callback/redirect URL must be http://opengist.domain/oauth/<github|gitea|openid-connect>/callback
 
 # To create a new OAuth2 application using GitHub : https://github.com/settings/applications/new
 github.client-key:
@@ -71,3 +71,9 @@ gitea.client-key:
 gitea.secret:
 # URL of the Gitea instance. Default: https://gitea.com/
 gitea.url: https://gitea.com/
+
+# To create a new OAuth2 application using OpenID Connect:
+oidc.client-key:
+oidc.secret:
+# Discovery endpoint of the OpenID provider
+oidc.discovery-url: