ESC should be made to work through a firewall proxy.

ESC uses two ways to communicate with the server. One is using the
mozilla gecko network stuff for getting web pages like that enrollment
UI.

The other way is using our little custom http library that does the actual
communications to TPS to do the operations such as Format and Pin Reset.

Therefore, I believe, but am not sure, that we would have to do some work
on the http library to work through a proxy.