It looks like you are trying to setup reverse proxy in https(port 443). Which is working but browser is not able to verify certificate. I believe if you try this setup under http (port 80) it will work. Certificate might be signed by https://192.168.112.57 correctly but it in that case it would be signed for 192.168.112.57 domain. proxying it will lead in to certificate error.
In firefox browser you have option to ignore certificate error. If you try in in firefox and ignore certificate verification, it should work.
