anchor.diff:  	{ok, State#state{version=0, origin=Origin, challenge={Key1, Key2},
   		eop=EOP}, Req4};
   %% Versions 7 and 8. Implementation follows the hybi 7 through 10 drafts.
  -%% @todo We don't need Origin?
   websocket_upgrade(<< Version >>, State, Req)
   		when Version =:= $7; Version =:= $8 ->
  -	{Origin, Req2} = cowboy_http_req:header(<<"Sec-Websocket-Origin">>, Req),
  -	{Key, Req3} = cowboy_http_req:header(<<"Sec-Websocket-Key">>, Req2),
  -	false = lists:member(undefined, [Origin, Key]),
  +	{Key, Req2} = cowboy_http_req:header(<<"Sec-Websocket-Key">>, Req),
  +	false = Key =:= undefined,
   	Challenge = hybi_challenge(Key),
  -	{ok, State#state{version=Version - $0, origin=Origin,
  -		challenge=Challenge}, Req3}.
  +	{ok, State#state{version=Version - $0, challenge=Challenge}, Req2}.
   
   -spec handler_init(#state{}, #http_req{}) -> ok | none().
   handler_init(State=#state{handler=Handler, opts=Opts},
  
positive.code: %% third part of the challenge key, because proxies will wait for
  %% a reply before sending it. Therefore we calculate the challenge
  %% key only in websocket_handshake/3.
  %% @todo Check Origin?
  websocket_upgrade(undefined, State, Req) ->
  	{Origin, Req2} = cowboy_http_req:header(<<"Origin">>, Req),
  	{Key1, Req3} = cowboy_http_req:header(<<"Sec-Websocket-Key1">>, Req2),
  
negative.code: 	websocket_upgrade(Version, State, Req4).
  
  %% @todo Handle the Sec-Websocket-Protocol header.
  %% @todo Reply a proper error, don't die, if a required header is undefined.
  -spec websocket_upgrade(undefined | <<_:8>>, #state{}, #http_req{})
  	-> {ok, #state{}, #http_req{}}.
  %% No version given. Assuming hixie-76 draft.
  