Steam OpenID 2.0 -> OpenID Connect Provider Proxy

Steam still uses the old OpenID 2.0 authentication protocol. Since ImperialPlugins.com has migrated to KeyCloak we were unable to migrate our old Steam logins as KeyCloak does not support OpenID 2.0.

This server will act as an OpenID Connect provider which will provide Steam authentication for you. This way you can use Steam logins in KeyCloak or any other OpenID Connect based authentication client.

Note: only "openid" and "profile" scopes are supported due limitations by Valve/Steam.

Add your Steam API Key as user-secrets like this: dotnet user-secrets set "Authentication:Steam:ApplicationKey" "MySteamApiKey"

Alternatively you can set it up via environment variables: -e Authentication__Steam__ApplicationKey: 'Your Steam ApiKey‘ (Keep in mind that this is easier but more insecure)

After that set up your redirect URI, ClientID and ClientSecret in the appsettings.json.

This service contains a health check endpoint at /health. It checks if the Steam login server is up.

A docker image is also available.

docker run -it \
    -e OpenID__RedirectUri=http://localhost:8080/auth/realms/master/broker/steam/endpoint \
    -e OpenID__ClientID=steamidp \ 
    -e OpenID__ClientSecret=mysecret \
    -e Authentication__Steam__ApplicationKey=MySteamApiKey \
    --restart unless-stopped \
    --name steamidp \
    imperialplugins/steam-openid-connect-provider

MIT