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diff --git a/src/cowboy_http_websocket.erl b/src/cowboy_http_websocket.erl
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+%% Copyright (c) 2011, Loïc Hoguin <[email protected]>
+%%
+%% Permission to use, copy, modify, and/or distribute this software for any
+%% purpose with or without fee is hereby granted, provided that the above
+%% copyright notice and this permission notice appear in all copies.
+%%
+%% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+%% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+%% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+%% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+%% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+%% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+%% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+-module(cowboy_http_websocket).
+-export([upgrade/3]).
+
+-include("include/types.hrl").
+-include("include/http.hrl").
+
+-record(state, {
+ handler :: module(),
+ opts :: term(),
+ origin = undefined :: undefined | string(),
+ challenge = undefined :: undefined | binary(),
+ timeout = infinity :: timeout(),
+ messages = undefined :: undefined | {atom(), atom(), atom()}
+}).
+
+-spec upgrade(Handler::module(), Opts::term(), Req::#http_req{}) -> ok.
+upgrade(Handler, Opts, Req) ->
+ case catch websocket_upgrade(#state{handler=Handler, opts=Opts}, Req) of
+ {ok, State, Req2} -> handler_init(State, Req2);
+ {'EXIT', _Reason} -> upgrade_error(Req)
+ end.
+
+-spec websocket_upgrade(State::#state{}, Req::#http_req{})
+ -> {ok, State::#state{}, Req::#http_req{}}.
+websocket_upgrade(State, Req=#http_req{socket=Socket, transport=Transport}) ->
+ {"Upgrade", Req2} = cowboy_http_req:header('Connection', Req),
+ {"WebSocket", Req3} = cowboy_http_req:header('Upgrade', Req2),
+ {Origin, Req4} = cowboy_http_req:header("Origin", Req3),
+ {Key1, Req5} = cowboy_http_req:header("Sec-Websocket-Key1", Req4),
+ {Key2, Req6} = cowboy_http_req:header("Sec-Websocket-Key2", Req5),
+ false = lists:member(undefined, [Origin, Key1, Key2]),
+ Transport:setopts(Socket, [binary]),
+ {ok, Key3, Req7} = cowboy_http_req:body(8, Req6),
+ Challenge = challenge(Key1, Key2, Key3),
+ {ok, State#state{origin=Origin, challenge=Challenge}, Req7}.
+
+-spec challenge(Key1::string(), Key2::string(), Key3::binary()) -> binary().
+challenge(Key1, Key2, Key3) ->
+ IntKey1 = key_to_integer(Key1),
+ IntKey2 = key_to_integer(Key2),
+ erlang:md5(<< IntKey1:32, IntKey2:32, Key3/binary >>).
+
+-spec key_to_integer(Key::string()) -> integer().
+key_to_integer(Key) ->
+ Number = list_to_integer([C || C <- Key, C >= $0, C =< $9]),
+ Spaces = length([C || C <- Key, C =:= 32]),
+ Number div Spaces.
+
+-spec handler_init(State::#state{}, Req::#http_req{}) -> ok.
+handler_init(State=#state{handler=Handler, opts=Opts},
+ Req=#http_req{transport=Transport}) ->
+ case catch Handler:websocket_init(Transport:name(), Req, Opts) of
+ {ok, Req2, HandlerState} ->
+ websocket_handshake(State, Req2, HandlerState);
+ {ok, Req2, HandlerState, Timeout} ->
+ websocket_handshake(State#state{timeout=Timeout},
+ Req2, HandlerState);
+ {'EXIT', _Reason} ->
+ upgrade_error(Req)
+ end.
+
+-spec upgrade_error(Req::#http_req{}) -> ok.
+upgrade_error(Req=#http_req{socket=Socket, transport=Transport}) ->
+ {ok, _Req} = cowboy_http_req:reply(400, [], [],
+ Req#http_req{resp_state=waiting}),
+ Transport:close(Socket).
+
+-spec websocket_handshake(State::#state{}, Req::#http_req{},
+ HandlerState::term()) -> ok.
+websocket_handshake(State=#state{origin=Origin, challenge=Challenge},
+ Req=#http_req{transport=Transport, raw_host=Host, raw_path=Path},
+ HandlerState) ->
+ Location = websocket_location(Transport:name(), Host, Path),
+ {ok, Req2} = cowboy_http_req:reply(
+ "101 WebSocket Protocol Handshake",
+ [{"Connection", "Upgrade"},
+ {"Upgrade", "WebSocket"},
+ {"Sec-WebSocket-Location", Location},
+ {"Sec-WebSocket-Origin", Origin}],
+ Challenge, Req#http_req{resp_state=waiting}),
+ handler_loop(State#state{messages=Transport:messages()},
+ Req2, HandlerState, <<>>).
+
+-spec websocket_location(TransName::atom(), Host::string(), Path::string())
+ -> string().
+websocket_location(ssl, Host, Path) ->
+ "wss://" ++ Host ++ Path;
+websocket_location(_Any, Host, Path) ->
+ "ws://" ++ Host ++ Path.
+
+-spec handler_loop(State::#state{}, Req::#http_req{},
+ HandlerState::term(), SoFar::binary()) -> ok.
+handler_loop(State=#state{messages={OK, Closed, Error}, timeout=Timeout},
+ Req=#http_req{socket=Socket, transport=Transport},
+ HandlerState, SoFar) ->
+ Transport:setopts(Socket, [{active, once}]),
+ receive
+ {OK, Socket, Data} ->
+ websocket_data(State, Req, HandlerState,
+ << SoFar/binary, Data/binary >>);
+ {Closed, Socket} ->
+ handler_terminate(State, Req, HandlerState, {error, closed});
+ {Error, Socket, Reason} ->
+ handler_terminate(State, Req, HandlerState, {error, Reason});
+ Message ->
+ handler_call(State, Req, HandlerState,
+ SoFar, Message, fun handler_loop/4)
+ after Timeout ->
+ websocket_close(State, Req, HandlerState, {normal, timeout})
+ end.
+
+-spec websocket_data(State::#state{}, Req::#http_req{},
+ HandlerState::term(), Data::binary()) -> ok.
+websocket_data(State, Req, HandlerState, << 255, 0, _Rest/bits >>) ->
+ websocket_close(State, Req, HandlerState, {normal, closed});
+websocket_data(State, Req, HandlerState, Data) when byte_size(Data) < 3 ->
+ handler_loop(State, Req, HandlerState, Data);
+websocket_data(State, Req, HandlerState, Data) ->
+ websocket_frame(State, Req, HandlerState, Data, binary:first(Data)).
+
+%% We do not support any frame type other than 0 yet. Just like the specs.
+-spec websocket_frame(State::#state{}, Req::#http_req{},
+ HandlerState::term(), Data::binary(), FrameType::byte()) -> ok.
+websocket_frame(State, Req, HandlerState, Data, 0) ->
+ case binary:match(Data, << 255 >>) of
+ {Pos, 1} ->
+ Pos2 = Pos - 1,
+ << 0, Frame:Pos2/binary, 255, Rest/bits >> = Data,
+ handler_call(State, Req, HandlerState,
+ Rest, {websocket, Frame}, fun websocket_data/4);
+ nomatch ->
+ %% @todo We probably should allow limiting frame length.
+ handler_loop(State, Req, HandlerState, Data)
+ end;
+websocket_frame(State, Req, HandlerState, _Data, _FrameType) ->
+ websocket_close(State, Req, HandlerState, {error, badframe}).
+
+-spec handler_call(State::#state{}, Req::#http_req{}, HandlerState::term(),
+ RemainingData::binary(), Message::term(), NextState::fun()) -> ok.
+handler_call(State=#state{handler=Handler}, Req, HandlerState,
+ RemainingData, Message, NextState) ->
+ case catch Handler:websocket_handle(Message, Req, HandlerState) of
+ {ok, Req2, HandlerState2} ->
+ NextState(State, Req2, HandlerState2, RemainingData);
+ {reply, Data, Req2, HandlerState2} ->
+ websocket_send(Data, Req2),
+ NextState(State, Req2, HandlerState2, RemainingData);
+ {shutdown, Req2, HandlerState2} ->
+ websocket_close(State, Req2, HandlerState2, {normal, shutdown});
+ {'EXIT', _Reason} ->
+ websocket_close(State, Req, HandlerState, {error, handler})
+ end.
+
+-spec websocket_send(Data::binary(), Req::#http_req{}) -> ok.
+websocket_send(Data, #http_req{socket=Socket, transport=Transport}) ->
+ Transport:send(Socket, << 0, Data/binary, 255 >>).
+
+-spec websocket_close(State::#state{}, Req::#http_req{},
+ HandlerState::term(), Reason::{atom(), atom()}) -> ok.
+websocket_close(State, Req=#http_req{socket=Socket, transport=Transport},
+ HandlerState, Reason) ->
+ Transport:send(Socket, << 255, 0 >>),
+ Transport:close(Socket),
+ handler_terminate(State, Req, HandlerState, Reason).
+
+-spec handler_terminate(State::#state{}, Req::#http_req{},
+ HandlerState::term(), Reason::atom() | {atom(), atom()}) -> ok.
+handler_terminate(#state{handler=Handler}, Req, HandlerState, Reason) ->
+ Handler:websocket_terminate(Reason, Req, HandlerState).