diff options
Diffstat (limited to 'src/cowboy_websocket.erl')
| -rw-r--r-- | src/cowboy_websocket.erl | 724 |
1 files changed, 391 insertions, 333 deletions
diff --git a/src/cowboy_websocket.erl b/src/cowboy_websocket.erl index 8c02ac7..debb69f 100644 --- a/src/cowboy_websocket.erl +++ b/src/cowboy_websocket.erl @@ -1,4 +1,4 @@ -%% Copyright (c) 2011-2012, Loïc Hoguin <[email protected]> +%% Copyright (c) 2011-2013, 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 @@ -12,7 +12,10 @@ %% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF %% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. -%% @doc WebSocket protocol implementation. +%% @doc Websocket protocol implementation. +%% +%% Cowboy supports versions 7 through 17 of the Websocket drafts. +%% It also supports RFC6455, the proposed standard for Websocket. -module(cowboy_websocket). %% API. @@ -21,52 +24,52 @@ %% Internal. -export([handler_loop/4]). +-type close_code() :: 1000..4999. +-export_type([close_code/0]). + -type frame() :: close | ping | pong | {text | binary | close | ping | pong, binary()} - | {close, 1000..4999, binary()}. + | {close, close_code(), binary()}. -export_type([frame/0]). -type opcode() :: 0 | 1 | 2 | 8 | 9 | 10. -type mask_key() :: 0..16#ffffffff. - -%% The websocket_data/4 function may be called multiple times for a message. -%% The websocket_dispatch/4 function is only called once for each message. --type frag_state() :: - undefined | %% no fragmentation has been seen. - {nofin, opcode()} | %% first fragment has been seen. - {nofin, opcode(), binary()} | %% first fragment has been unmasked. - {fin, opcode(), binary()}. %% last fragment has been seen. +-type frag_state() :: undefined + | {nofin, opcode(), binary()} | {fin, opcode(), binary()}. -record(state, { + env :: cowboy_middleware:env(), socket = undefined :: inet:socket(), transport = undefined :: module(), - version :: 0 | 7 | 8 | 13, handler :: module(), - opts :: any(), - challenge = undefined :: undefined | binary() | {binary(), binary()}, + handler_opts :: any(), + key = undefined :: undefined | binary(), timeout = infinity :: timeout(), timeout_ref = undefined :: undefined | reference(), messages = undefined :: undefined | {atom(), atom(), atom()}, hibernate = false :: boolean(), - eop :: undefined | tuple(), %% hixie-76 specific. - origin = undefined :: undefined | binary(), %% hixie-76 specific. - frag_state = undefined :: frag_state() + frag_state = undefined :: frag_state(), + utf8_state = <<>> :: binary() }). -%% @doc Upgrade a HTTP request to the WebSocket protocol. +%% @doc Upgrade an HTTP request to the Websocket protocol. %% -%% You do not need to call this function manually. To upgrade to the WebSocket +%% You do not need to call this function manually. To upgrade to the Websocket %% protocol, you simply need to return <em>{upgrade, protocol, {@module}}</em> %% in your <em>cowboy_http_handler:init/3</em> handler function. --spec upgrade(pid(), module(), any(), cowboy_req:req()) -> closed. -upgrade(ListenerPid, Handler, Opts, Req) -> +-spec upgrade(Req, Env, module(), any()) + -> {ok, Req, Env} | {error, 400, Req} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(), Env::cowboy_middleware:env(). +upgrade(Req, Env, Handler, HandlerOpts) -> + {_, ListenerPid} = lists:keyfind(listener, 1, Env), ranch_listener:remove_connection(ListenerPid), - {ok, Transport, Socket} = cowboy_req:transport(Req), - State = #state{socket=Socket, transport=Transport, - handler=Handler, opts=Opts}, + [Socket, Transport] = cowboy_req:get([socket, transport], Req), + State = #state{env=Env, socket=Socket, transport=Transport, + handler=Handler, handler_opts=HandlerOpts}, case catch websocket_upgrade(State, Req) of {ok, State2, Req2} -> handler_init(State2, Req2); - {'EXIT', _Reason} -> upgrade_error(Req) + {'EXIT', _Reason} -> upgrade_error(Req, Env) end. -spec websocket_upgrade(#state{}, Req) @@ -79,41 +82,21 @@ websocket_upgrade(State, Req) -> {ok, [<<"websocket">>], Req3} = cowboy_req:parse_header(<<"upgrade">>, Req2), {Version, Req4} = cowboy_req:header(<<"sec-websocket-version">>, Req3), - 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{}, Req) - -> {ok, #state{}, Req} when Req::cowboy_req:req(). -%% No version given. Assuming hixie-76 draft. -%% -%% We need to wait to send a reply back before trying to read the -%% 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. -websocket_upgrade(undefined, State, Req) -> - {Origin, Req2} = cowboy_req:header(<<"origin">>, Req), - {Key1, Req3} = cowboy_req:header(<<"sec-websocket-key1">>, Req2), - {Key2, Req4} = cowboy_req:header(<<"sec-websocket-key2">>, Req3), - false = lists:member(undefined, [Origin, Key1, Key2]), - EOP = binary:compile_pattern(<< 255 >>), - {ok, State#state{version=0, origin=Origin, challenge={Key1, Key2}, - eop=EOP}, cowboy_req:set_meta(websocket_version, 0, Req4)}; -%% Versions 7 and 8. Implementation follows the hybi 7 through 17 drafts. -websocket_upgrade(Version, State, Req) - when Version =:= <<"7">>; Version =:= <<"8">>; - Version =:= <<"13">> -> - {Key, Req2} = cowboy_req:header(<<"sec-websocket-key">>, Req), - false = Key =:= undefined, - Challenge = hybi_challenge(Key), IntVersion = list_to_integer(binary_to_list(Version)), - {ok, State#state{version=IntVersion, challenge=Challenge}, - cowboy_req:set_meta(websocket_version, IntVersion, Req2)}. - --spec handler_init(#state{}, cowboy_req:req()) -> closed. -handler_init(State=#state{transport=Transport, handler=Handler, opts=Opts}, - Req) -> - try Handler:websocket_init(Transport:name(), Req, Opts) of + true = (IntVersion =:= 7) orelse (IntVersion =:= 8) + orelse (IntVersion =:= 13), + {Key, Req5} = cowboy_req:header(<<"sec-websocket-key">>, Req4), + false = Key =:= undefined, + {ok, State#state{key=Key}, + cowboy_req:set_meta(websocket_version, IntVersion, Req5)}. + +-spec handler_init(#state{}, Req) + -> {ok, Req, cowboy_middleware:env()} | {error, 400, Req} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(). +handler_init(State=#state{env=Env, transport=Transport, + handler=Handler, handler_opts=HandlerOpts}, Req) -> + try Handler:websocket_init(Transport:name(), Req, HandlerOpts) of {ok, Req2, HandlerState} -> websocket_handshake(State, Req2, HandlerState); {ok, Req2, HandlerState, hibernate} -> @@ -127,60 +110,36 @@ handler_init(State=#state{transport=Transport, handler=Handler, opts=Opts}, hibernate=true}, Req2, HandlerState); {shutdown, Req2} -> cowboy_req:ensure_response(Req2, 400), - closed + {ok, Req2, [{result, closed}|Env]} catch Class:Reason -> - upgrade_error(Req), error_logger:error_msg( "** Cowboy handler ~p terminating in ~p/~p~n" " for the reason ~p:~p~n** Options were ~p~n" "** Request was ~p~n** Stacktrace: ~p~n~n", - [Handler, websocket_init, 3, Class, Reason, Opts, - cowboy_req:to_list(Req),erlang:get_stacktrace()]) + [Handler, websocket_init, 3, Class, Reason, HandlerOpts, + cowboy_req:to_list(Req),erlang:get_stacktrace()]), + upgrade_error(Req, Env) end. --spec upgrade_error(cowboy_req:req()) -> closed. -upgrade_error(Req) -> +%% Only send an error reply if there is no resp_sent message. +-spec upgrade_error(Req, Env) -> {ok, Req, Env} | {error, 400, Req} + when Req::cowboy_req:req(), Env::cowboy_middleware:env(). +upgrade_error(Req, Env) -> receive - {cowboy_req, resp_sent} -> closed + {cowboy_req, resp_sent} -> + {ok, Req, [{result, closed}|Env]} after 0 -> - _ = cowboy_req:reply(400, [], [], Req), - closed + {error, 400, Req} end. --spec websocket_handshake(#state{}, cowboy_req:req(), any()) -> closed. -websocket_handshake(State=#state{socket=Socket, transport=Transport, - version=0, origin=Origin, challenge={Key1, Key2}}, - Req, HandlerState) -> - {<< "http", Location/binary >>, Req1} = cowboy_req:url(Req), - {ok, Req2} = cowboy_req:upgrade_reply( - <<"101 WebSocket Protocol Handshake">>, - [{<<"upgrade">>, <<"WebSocket">>}, - {<<"sec-websocket-location">>, << "ws", Location/binary >>}, - {<<"sec-websocket-origin">>, Origin}], - Req1), - %% Flush the resp_sent message before moving on. - receive {cowboy_req, resp_sent} -> ok after 0 -> ok end, - %% We replied with a proper response. Proxies should be happy enough, - %% we can now read the 8 last bytes of the challenge keys and send - %% the challenge response directly to the socket. - %% - %% We use a trick here to read exactly 8 bytes of the body regardless - %% of what's in the buffer. - {ok, Req3} = cowboy_req:init_stream( - fun cowboy_http:te_identity/2, {0, 8}, - fun cowboy_http:ce_identity/1, Req2), - case cowboy_req:body(Req3) of - {ok, Key3, Req4} -> - Challenge = hixie76_challenge(Key1, Key2, Key3), - Transport:send(Socket, Challenge), - handler_before_loop(State#state{messages=Transport:messages()}, - Req4, HandlerState, <<>>); - _Any -> - %% If an error happened reading the body, stop there. - handler_terminate(State, Req3, HandlerState, {error, closed}) - end; -websocket_handshake(State=#state{transport=Transport, challenge=Challenge}, +-spec websocket_handshake(#state{}, Req, any()) + -> {ok, Req, cowboy_middleware:env()} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(). +websocket_handshake(State=#state{transport=Transport, key=Key}, Req, HandlerState) -> + Challenge = base64:encode(crypto:sha( + << Key/binary, "258EAFA5-E914-47DA-95CA-C5AB0DC85B11" >>)), {ok, Req2} = cowboy_req:upgrade_reply( 101, [{<<"upgrade">>, <<"websocket">>}, @@ -189,17 +148,19 @@ websocket_handshake(State=#state{transport=Transport, challenge=Challenge}, %% Flush the resp_sent message before moving on. receive {cowboy_req, resp_sent} -> ok after 0 -> ok end, State2 = handler_loop_timeout(State), - handler_before_loop(State2#state{messages=Transport:messages()}, - Req2, HandlerState, <<>>). + handler_before_loop(State2#state{key=undefined, + messages=Transport:messages()}, Req2, HandlerState, <<>>). --spec handler_before_loop(#state{}, cowboy_req:req(), any(), binary()) -> closed. +-spec handler_before_loop(#state{}, Req, any(), binary()) + -> {ok, Req, cowboy_middleware:env()} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(). handler_before_loop(State=#state{ socket=Socket, transport=Transport, hibernate=true}, Req, HandlerState, SoFar) -> Transport:setopts(Socket, [{active, once}]), - catch erlang:hibernate(?MODULE, handler_loop, - [State#state{hibernate=false}, Req, HandlerState, SoFar]), - closed; + {suspend, ?MODULE, handler_loop, + [State#state{hibernate=false}, Req, HandlerState, SoFar]}; handler_before_loop(State=#state{socket=Socket, transport=Transport}, Req, HandlerState, SoFar) -> Transport:setopts(Socket, [{active, once}]), @@ -215,10 +176,12 @@ handler_loop_timeout(State=#state{timeout=Timeout, timeout_ref=PrevRef}) -> State#state{timeout_ref=TRef}. %% @private --spec handler_loop(#state{}, cowboy_req:req(), any(), binary()) -> closed. -handler_loop(State=#state{ - socket=Socket, messages={OK, Closed, Error}, timeout_ref=TRef}, - Req, HandlerState, SoFar) -> +-spec handler_loop(#state{}, Req, any(), binary()) + -> {ok, Req, cowboy_middleware:env()} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(). +handler_loop(State=#state{socket=Socket, messages={OK, Closed, Error}, + timeout_ref=TRef}, Req, HandlerState, SoFar) -> receive {OK, Socket, Data} -> State2 = handler_loop_timeout(State), @@ -237,191 +200,298 @@ handler_loop(State=#state{ SoFar, websocket_info, Message, fun handler_before_loop/4) end. --spec websocket_data(#state{}, cowboy_req:req(), any(), binary()) -> closed. -%% No more data. -websocket_data(State, Req, HandlerState, <<>>) -> - handler_before_loop(State, Req, HandlerState, <<>>); -%% hixie-76 close frame. -websocket_data(State=#state{version=0}, Req, HandlerState, - << 255, 0, _Rest/binary >>) -> - websocket_close(State, Req, HandlerState, {normal, closed}); -%% hixie-76 data frame. We only support the frame type 0, same as the specs. -websocket_data(State=#state{version=0, eop=EOP}, Req, HandlerState, - Data = << 0, _/binary >>) -> - case binary:match(Data, EOP) of - {Pos, 1} -> - Pos2 = Pos - 1, - << 0, Payload:Pos2/binary, 255, Rest/bits >> = Data, - handler_call(State, Req, HandlerState, - Rest, websocket_handle, {text, Payload}, fun websocket_data/4); - nomatch -> - %% @todo We probably should allow limiting frame length. - handler_before_loop(State, Req, HandlerState, Data) - end; -%% incomplete hybi data frame. -websocket_data(State=#state{version=Version}, Req, HandlerState, Data) - when Version =/= 0, byte_size(Data) =:= 1 -> - handler_before_loop(State, Req, HandlerState, Data); -%% 7 bit payload length prefix exists +%% All frames passing through this function are considered valid, +%% with the only exception of text and close frames with a payload +%% which may still contain errors. +-spec websocket_data(#state{}, Req, any(), binary()) + -> {ok, Req, cowboy_middleware:env()} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(). +%% RSV bits MUST be 0 unless an extension is negotiated +%% that defines meanings for non-zero values. +websocket_data(State, Req, HandlerState, << _:1, Rsv:3, _/bits >>) + when Rsv =/= 0 -> + websocket_close(State, Req, HandlerState, {error, badframe}); +%% Invalid opcode. Note that these opcodes may be used by extensions. +websocket_data(State, Req, HandlerState, << _:4, Opcode:4, _/bits >>) + when Opcode > 2, Opcode =/= 8, Opcode =/= 9, Opcode =/= 10 -> + websocket_close(State, Req, HandlerState, {error, badframe}); +%% Control frames MUST NOT be fragmented. +websocket_data(State, Req, HandlerState, << 0:1, _:3, Opcode:4, _/bits >>) + when Opcode >= 8 -> + websocket_close(State, Req, HandlerState, {error, badframe}); +%% A frame MUST NOT use the zero opcode unless fragmentation was initiated. +websocket_data(State=#state{frag_state=undefined}, Req, HandlerState, + << _:4, 0:4, _/bits >>) -> + websocket_close(State, Req, HandlerState, {error, badframe}); +%% Non-control opcode when expecting control message or next fragment. +websocket_data(State=#state{frag_state={nofin, _, _}}, Req, HandlerState, + << _:4, Opcode:4, _/bits >>) + when Opcode =/= 0, Opcode < 8 -> + websocket_close(State, Req, HandlerState, {error, badframe}); +%% Close control frame length MUST be 0 or >= 2. +websocket_data(State, Req, HandlerState, << _:4, 8:4, _:1, 1:7, _/bits >>) -> + websocket_close(State, Req, HandlerState, {error, badframe}); +%% Close control frame with incomplete close code. Need more data. websocket_data(State, Req, HandlerState, - << Fin:1, Rsv:3, Opcode:4, Mask:1, PayloadLen:7, Rest/bits >> - = Data) when PayloadLen < 126 -> + Data = << _:4, 8:4, 1:1, Len:7, _/bits >>) + when Len > 1, byte_size(Data) < 8 -> + handler_before_loop(State, Req, HandlerState, Data); +%% 7 bits payload length. +websocket_data(State, Req, HandlerState, << Fin:1, _Rsv:3, Opcode:4, 1:1, + Len:7, MaskKey:32, Rest/bits >>) + when Len < 126 -> websocket_data(State, Req, HandlerState, - Fin, Rsv, Opcode, Mask, PayloadLen, Rest, Data); -%% 7+16 bits payload length prefix exists -websocket_data(State, Req, HandlerState, - << Fin:1, Rsv:3, Opcode:4, Mask:1, 126:7, PayloadLen:16, Rest/bits >> - = Data) when PayloadLen > 125 -> + Opcode, Len, MaskKey, Rest, Fin); +%% 16 bits payload length. +websocket_data(State, Req, HandlerState, << Fin:1, _Rsv:3, Opcode:4, 1:1, + 126:7, Len:16, MaskKey:32, Rest/bits >>) + when Len > 125, Opcode < 8 -> websocket_data(State, Req, HandlerState, - Fin, Rsv, Opcode, Mask, PayloadLen, Rest, Data); -%% 7+16 bits payload length prefix missing -websocket_data(State, Req, HandlerState, - << _Fin:1, _Rsv:3, _Opcode:4, _Mask:1, 126:7, Rest/bits >> - = Data) when byte_size(Rest) < 2 -> - handler_before_loop(State, Req, HandlerState, Data); -%% 7+64 bits payload length prefix exists -websocket_data(State, Req, HandlerState, - << Fin:1, Rsv:3, Opcode:4, Mask:1, 127:7, 0:1, PayloadLen:63, - Rest/bits >> = Data) when PayloadLen > 16#FFFF -> + Opcode, Len, MaskKey, Rest, Fin); +%% 63 bits payload length. +websocket_data(State, Req, HandlerState, << Fin:1, _Rsv:3, Opcode:4, 1:1, + 127:7, 0:1, Len:63, MaskKey:32, Rest/bits >>) + when Len > 16#ffff, Opcode < 8 -> websocket_data(State, Req, HandlerState, - Fin, Rsv, Opcode, Mask, PayloadLen, Rest, Data); -%% 7+64 bits payload length prefix missing -websocket_data(State, Req, HandlerState, - << _Fin:1, _Rsv:3, _Opcode:4, _Mask:1, 127:7, Rest/bits >> - = Data) when byte_size(Rest) < 8 -> - handler_before_loop(State, Req, HandlerState, Data); -%% invalid payload length prefix. -websocket_data(State, Req, HandlerState, _Data) -> - websocket_close(State, Req, HandlerState, {error, badframe}). - --spec websocket_data(#state{}, cowboy_req:req(), any(), non_neg_integer(), - non_neg_integer(), non_neg_integer(), non_neg_integer(), - non_neg_integer(), binary(), binary()) -> closed. -%% A fragmented message MUST start a non-zero opcode. -websocket_data(State=#state{frag_state=undefined}, Req, HandlerState, - _Fin=0, _Rsv=0, _Opcode=0, _Mask, _PayloadLen, _Rest, _Buffer) -> + Opcode, Len, MaskKey, Rest, Fin); +%% When payload length is over 63 bits, the most significant bit MUST be 0. +websocket_data(State, Req, HandlerState, << _:8, 1:1, 127:7, 1:1, _/bits >>) -> websocket_close(State, Req, HandlerState, {error, badframe}); -%% A control message MUST NOT be fragmented. -websocket_data(State, Req, HandlerState, _Fin=0, _Rsv=0, Opcode, _Mask, - _PayloadLen, _Rest, _Buffer) when Opcode >= 8 -> +%% All frames sent from the client to the server are masked. +websocket_data(State, Req, HandlerState, << _:8, 0:1, _/bits >>) -> websocket_close(State, Req, HandlerState, {error, badframe}); -%% The opcode is only included in the first message fragment. -websocket_data(State=#state{frag_state=undefined}, Req, HandlerState, - _Fin=0, _Rsv=0, Opcode, Mask, PayloadLen, Rest, Data) -> - websocket_before_unmask( - State#state{frag_state={nofin, Opcode}}, Req, HandlerState, - Data, Rest, 0, Mask, PayloadLen); -%% non-control opcode when expecting control message or next fragment. -websocket_data(State=#state{frag_state={nofin, _, _}}, Req, HandlerState, _Fin, - _Rsv=0, Opcode, _Mask, _Ln, _Rest, _Data) when Opcode > 0, Opcode < 8 -> +%% For the next two clauses, it can be one of the following: +%% +%% * The minimal number of bytes MUST be used to encode the length +%% * All control frames MUST have a payload length of 125 bytes or less +websocket_data(State, Req, HandlerState, << _:9, 126:7, _:48, _/bits >>) -> websocket_close(State, Req, HandlerState, {error, badframe}); -%% If the first message fragment was incomplete, retry unmasking. -websocket_data(State=#state{frag_state={nofin, Opcode}}, Req, HandlerState, - _Fin=0, _Rsv=0, Opcode, Mask, PayloadLen, Rest, Data) -> - websocket_before_unmask( - State#state{frag_state={nofin, Opcode}}, Req, HandlerState, - Data, Rest, 0, Mask, PayloadLen); -%% if the opcode is zero and the fin flag is zero, unmask and await next. -websocket_data(State=#state{frag_state={nofin, _Opcode, _Payloads}}, Req, - HandlerState, _Fin=0, _Rsv=0, _Opcode2=0, Mask, PayloadLen, Rest, - Data) -> - websocket_before_unmask( - State, Req, HandlerState, Data, Rest, 0, Mask, PayloadLen); -%% when the last fragment is seen. Update the fragmentation status. -websocket_data(State=#state{frag_state={nofin, Opcode, Payloads}}, Req, - HandlerState, _Fin=1, _Rsv=0, _Opcode=0, Mask, PayloadLen, Rest, - Data) -> - websocket_before_unmask( - State#state{frag_state={fin, Opcode, Payloads}}, - Req, HandlerState, Data, Rest, 0, Mask, PayloadLen); -%% control messages MUST NOT use 7+16 bits or 7+64 bits payload length prefixes -websocket_data(State, Req, HandlerState, _Fin, _Rsv, Opcode, _Mask, PayloadLen, - _Rest, _Data) when Opcode >= 8, PayloadLen > 125 -> - websocket_close(State, Req, HandlerState, {error, badframe}); -%% unfragmented message. unmask and dispatch the message. -websocket_data(State=#state{version=Version}, Req, HandlerState, _Fin=1, _Rsv=0, - Opcode, Mask, PayloadLen, Rest, Data) when Version =/= 0 -> - websocket_before_unmask( - State, Req, HandlerState, Data, Rest, Opcode, Mask, PayloadLen); -%% Something was wrong with the frame. Close the connection. -websocket_data(State, Req, HandlerState, _Fin, _Rsv, _Opcode, _Mask, - _PayloadLen, _Rest, _Data) -> - websocket_close(State, Req, HandlerState, {error, badframe}). - -%% hybi routing depending on whether unmasking is needed. --spec websocket_before_unmask(#state{}, cowboy_req:req(), any(), binary(), - binary(), opcode(), 0 | 1, non_neg_integer() | undefined) -> closed. -websocket_before_unmask(State, Req, HandlerState, Data, - Rest, Opcode, Mask, PayloadLen) -> - case {Mask, PayloadLen} of - {0, 0} -> - websocket_dispatch(State, Req, HandlerState, Rest, Opcode, <<>>); - {1, N} when N + 4 > byte_size(Rest); N =:= undefined -> - %% @todo We probably should allow limiting frame length. - handler_before_loop(State, Req, HandlerState, Data); - {1, _N} -> - << MaskKey:32, Payload:PayloadLen/binary, Rest2/bits >> = Rest, - websocket_unmask(State, Req, HandlerState, Rest2, - Opcode, Payload, MaskKey) - end. - -%% hybi unmasking. --spec websocket_unmask(#state{}, cowboy_req:req(), any(), binary(), - opcode(), binary(), mask_key()) -> closed. -websocket_unmask(State, Req, HandlerState, RemainingData, - Opcode, Payload, MaskKey) -> - websocket_unmask(State, Req, HandlerState, RemainingData, - Opcode, Payload, MaskKey, <<>>). - --spec websocket_unmask(#state{}, cowboy_req:req(), any(), binary(), - opcode(), binary(), mask_key(), binary()) -> closed. -websocket_unmask(State, Req, HandlerState, RemainingData, - Opcode, << O:32, Rest/bits >>, MaskKey, Acc) -> +websocket_data(State, Req, HandlerState, << _:9, 127:7, _:96, _/bits >>) -> + websocket_close(State, Req, HandlerState, {error, badframe}); +%% Need more data. +websocket_data(State, Req, HandlerState, Data) -> + handler_before_loop(State, Req, HandlerState, Data). + +%% Initialize or update fragmentation state. +-spec websocket_data(#state{}, Req, any(), + opcode(), non_neg_integer(), mask_key(), binary(), 0 | 1) + -> {ok, Req, cowboy_middleware:env()} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(). +%% The opcode is only included in the first frame fragment. +websocket_data(State=#state{frag_state=undefined}, Req, HandlerState, + Opcode, Len, MaskKey, Data, 0) -> + websocket_payload(State#state{frag_state={nofin, Opcode, <<>>}}, + Req, HandlerState, 0, Len, MaskKey, <<>>, Data); +%% Subsequent frame fragments. +websocket_data(State=#state{frag_state={nofin, _, _}}, Req, HandlerState, + 0, Len, MaskKey, Data, 0) -> + websocket_payload(State, Req, HandlerState, + 0, Len, MaskKey, <<>>, Data); +%% Final frame fragment. +websocket_data(State=#state{frag_state={nofin, Opcode, SoFar}}, + Req, HandlerState, 0, Len, MaskKey, Data, 1) -> + websocket_payload(State#state{frag_state={fin, Opcode, SoFar}}, + Req, HandlerState, 0, Len, MaskKey, <<>>, Data); +%% Unfragmented frame. +websocket_data(State, Req, HandlerState, Opcode, Len, MaskKey, Data, 1) -> + websocket_payload(State, Req, HandlerState, + Opcode, Len, MaskKey, <<>>, Data). + +-spec websocket_payload(#state{}, Req, any(), + opcode(), non_neg_integer(), mask_key(), binary(), binary()) + -> {ok, Req, cowboy_middleware:env()} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(). +%% Close control frames with a payload MUST contain a valid close code. +websocket_payload(State, Req, HandlerState, + Opcode=8, Len, MaskKey, <<>>, << MaskedCode:2/binary, Rest/bits >>) -> + Unmasked = << Code:16 >> = websocket_unmask(MaskedCode, MaskKey, <<>>), + if Code < 1000; Code =:= 1004; Code =:= 1005; Code =:= 1006; + (Code > 1011) and (Code < 3000); Code > 4999 -> + websocket_close(State, Req, HandlerState, {error, badframe}); + true -> + websocket_payload(State, Req, HandlerState, + Opcode, Len - 2, MaskKey, Unmasked, Rest) + end; +%% Text frames and close control frames MUST have a payload that is valid UTF-8. +websocket_payload(State=#state{utf8_state=Incomplete}, + Req, HandlerState, Opcode, Len, MaskKey, Unmasked, Data) + when (byte_size(Data) < Len) andalso ((Opcode =:= 1) orelse + ((Opcode =:= 8) andalso (Unmasked =/= <<>>))) -> + Unmasked2 = websocket_unmask(Data, + rotate_mask_key(MaskKey, byte_size(Unmasked)), <<>>), + case is_utf8(<< Incomplete/binary, Unmasked2/binary >>) of + false -> + websocket_close(State, Req, HandlerState, {error, badencoding}); + Utf8State -> + websocket_payload_loop(State#state{utf8_state=Utf8State}, + Req, HandlerState, Opcode, Len - byte_size(Data), MaskKey, + << Unmasked/binary, Unmasked2/binary >>) + end; +websocket_payload(State=#state{utf8_state=Incomplete}, + Req, HandlerState, Opcode, Len, MaskKey, Unmasked, Data) + when Opcode =:= 1; (Opcode =:= 8) and (Unmasked =/= <<>>) -> + << End:Len/binary, Rest/bits >> = Data, + Unmasked2 = websocket_unmask(End, + rotate_mask_key(MaskKey, byte_size(Unmasked)), <<>>), + case is_utf8(<< Incomplete/binary, Unmasked2/binary >>) of + <<>> -> + websocket_dispatch(State#state{utf8_state= <<>>}, + Req, HandlerState, Rest, Opcode, + << Unmasked/binary, Unmasked2/binary >>); + _ -> + websocket_close(State, Req, HandlerState, {error, badencoding}) + end; +%% Fragmented text frames may cut payload in the middle of UTF-8 codepoints. +websocket_payload(State=#state{frag_state={_, 1, _}, utf8_state=Incomplete}, + Req, HandlerState, Opcode=0, Len, MaskKey, Unmasked, Data) + when byte_size(Data) < Len -> + Unmasked2 = websocket_unmask(Data, + rotate_mask_key(MaskKey, byte_size(Unmasked)), <<>>), + case is_utf8(<< Incomplete/binary, Unmasked2/binary >>) of + false -> + websocket_close(State, Req, HandlerState, {error, badencoding}); + Utf8State -> + websocket_payload_loop(State#state{utf8_state=Utf8State}, + Req, HandlerState, Opcode, Len - byte_size(Data), MaskKey, + << Unmasked/binary, Unmasked2/binary >>) + end; +websocket_payload(State=#state{frag_state={Fin, 1, _}, utf8_state=Incomplete}, + Req, HandlerState, Opcode=0, Len, MaskKey, Unmasked, Data) -> + << End:Len/binary, Rest/bits >> = Data, + Unmasked2 = websocket_unmask(End, + rotate_mask_key(MaskKey, byte_size(Unmasked)), <<>>), + case is_utf8(<< Incomplete/binary, Unmasked2/binary >>) of + <<>> -> + websocket_dispatch(State#state{utf8_state= <<>>}, + Req, HandlerState, Rest, Opcode, + << Unmasked/binary, Unmasked2/binary >>); + Utf8State when is_binary(Utf8State), Fin =:= nofin -> + websocket_dispatch(State#state{utf8_state=Utf8State}, + Req, HandlerState, Rest, Opcode, + << Unmasked/binary, Unmasked2/binary >>); + _ -> + websocket_close(State, Req, HandlerState, {error, badencoding}) + end; +%% Other frames have a binary payload. +websocket_payload(State, Req, HandlerState, + Opcode, Len, MaskKey, Unmasked, Data) + when byte_size(Data) < Len -> + Unmasked2 = websocket_unmask(Data, + rotate_mask_key(MaskKey, byte_size(Unmasked)), Unmasked), + websocket_payload_loop(State, Req, HandlerState, + Opcode, Len - byte_size(Data), MaskKey, Unmasked2); +websocket_payload(State, Req, HandlerState, + Opcode, Len, MaskKey, Unmasked, Data) -> + << End:Len/binary, Rest/bits >> = Data, + Unmasked2 = websocket_unmask(End, + rotate_mask_key(MaskKey, byte_size(Unmasked)), Unmasked), + websocket_dispatch(State, Req, HandlerState, Rest, Opcode, Unmasked2). + +-spec websocket_unmask(B, mask_key(), B) -> B when B::binary(). +websocket_unmask(<<>>, _, Unmasked) -> + Unmasked; +websocket_unmask(<< O:32, Rest/bits >>, MaskKey, Acc) -> T = O bxor MaskKey, - websocket_unmask(State, Req, HandlerState, RemainingData, - Opcode, Rest, MaskKey, << Acc/binary, T:32 >>); -websocket_unmask(State, Req, HandlerState, RemainingData, - Opcode, << O:24 >>, MaskKey, Acc) -> + websocket_unmask(Rest, MaskKey, << Acc/binary, T:32 >>); +websocket_unmask(<< O:24 >>, MaskKey, Acc) -> << MaskKey2:24, _:8 >> = << MaskKey:32 >>, T = O bxor MaskKey2, - websocket_dispatch(State, Req, HandlerState, RemainingData, - Opcode, << Acc/binary, T:24 >>); -websocket_unmask(State, Req, HandlerState, RemainingData, - Opcode, << O:16 >>, MaskKey, Acc) -> + << Acc/binary, T:24 >>; +websocket_unmask(<< O:16 >>, MaskKey, Acc) -> << MaskKey2:16, _:16 >> = << MaskKey:32 >>, T = O bxor MaskKey2, - websocket_dispatch(State, Req, HandlerState, RemainingData, - Opcode, << Acc/binary, T:16 >>); -websocket_unmask(State, Req, HandlerState, RemainingData, - Opcode, << O:8 >>, MaskKey, Acc) -> + << Acc/binary, T:16 >>; +websocket_unmask(<< O:8 >>, MaskKey, Acc) -> << MaskKey2:8, _:24 >> = << MaskKey:32 >>, T = O bxor MaskKey2, - websocket_dispatch(State, Req, HandlerState, RemainingData, - Opcode, << Acc/binary, T:8 >>); -websocket_unmask(State, Req, HandlerState, RemainingData, - Opcode, <<>>, _MaskKey, Acc) -> - websocket_dispatch(State, Req, HandlerState, RemainingData, - Opcode, Acc). + << Acc/binary, T:8 >>. + +%% Because we unmask on the fly we need to continue from the right mask byte. +-spec rotate_mask_key(mask_key(), non_neg_integer()) -> mask_key(). +rotate_mask_key(MaskKey, UnmaskedLen) -> + Left = UnmaskedLen rem 4, + Right = 4 - Left, + (MaskKey bsl (Left * 8)) + (MaskKey bsr (Right * 8)). + +%% Returns <<>> if the argument is valid UTF-8, false if not, +%% or the incomplete part of the argument if we need more data. +-spec is_utf8(binary()) -> false | binary(). +is_utf8(Valid = <<>>) -> + Valid; +is_utf8(<< _/utf8, Rest/binary >>) -> + is_utf8(Rest); +%% 2 bytes. Codepages C0 and C1 are invalid; fail early. +is_utf8(<< 2#1100000:7, _/bits >>) -> + false; +is_utf8(Incomplete = << 2#110:3, _:5 >>) -> + Incomplete; +%% 3 bytes. +is_utf8(Incomplete = << 2#1110:4, _:4 >>) -> + Incomplete; +is_utf8(Incomplete = << 2#1110:4, _:4, 2#10:2, _:6 >>) -> + Incomplete; +%% 4 bytes. Codepage F4 may have invalid values greater than 0x10FFFF. +is_utf8(<< 2#11110100:8, 2#10:2, High:6, _/bits >>) when High >= 2#10000 -> + false; +is_utf8(Incomplete = << 2#11110:5, _:3 >>) -> + Incomplete; +is_utf8(Incomplete = << 2#11110:5, _:3, 2#10:2, _:6 >>) -> + Incomplete; +is_utf8(Incomplete = << 2#11110:5, _:3, 2#10:2, _:6, 2#10:2, _:6 >>) -> + Incomplete; +%% Invalid. +is_utf8(_) -> + false. + +-spec websocket_payload_loop(#state{}, Req, any(), + opcode(), non_neg_integer(), mask_key(), binary()) + -> {ok, Req, cowboy_middleware:env()} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(). +websocket_payload_loop(State=#state{socket=Socket, transport=Transport, + messages={OK, Closed, Error}, timeout_ref=TRef}, + Req, HandlerState, Opcode, Len, MaskKey, Unmasked) -> + Transport:setopts(Socket, [{active, once}]), + receive + {OK, Socket, Data} -> + State2 = handler_loop_timeout(State), + websocket_payload(State2, Req, HandlerState, + Opcode, Len, MaskKey, Unmasked, Data); + {Closed, Socket} -> + handler_terminate(State, Req, HandlerState, {error, closed}); + {Error, Socket, Reason} -> + handler_terminate(State, Req, HandlerState, {error, Reason}); + {timeout, TRef, ?MODULE} -> + websocket_close(State, Req, HandlerState, {normal, timeout}); + {timeout, OlderTRef, ?MODULE} when is_reference(OlderTRef) -> + websocket_payload_loop(State, Req, HandlerState, + Opcode, Len, MaskKey, Unmasked); + Message -> + handler_call(State, Req, HandlerState, + <<>>, websocket_info, Message, + fun (State2, Req2, HandlerState2, _) -> + websocket_payload_loop(State2, Req2, HandlerState2, + Opcode, Len, MaskKey, Unmasked) + end) + end. -%% hybi dispatching. --spec websocket_dispatch(#state{}, cowboy_req:req(), any(), binary(), - opcode(), binary()) -> closed. -%% First frame of a fragmented message unmasked. Expect intermediate or last. -websocket_dispatch(State=#state{frag_state={nofin, Opcode}}, Req, HandlerState, - RemainingData, 0, Payload) -> - websocket_data(State#state{frag_state={nofin, Opcode, Payload}}, - Req, HandlerState, RemainingData); -%% Intermediate frame of a fragmented message unmasked. Add payload to buffer. -websocket_dispatch(State=#state{frag_state={nofin, Opcode, Payloads}}, Req, - HandlerState, RemainingData, 0, Payload) -> +-spec websocket_dispatch(#state{}, Req, any(), binary(), opcode(), binary()) + -> {ok, Req, cowboy_middleware:env()} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(). +%% Continuation frame. +websocket_dispatch(State=#state{frag_state={nofin, Opcode, SoFar}}, + Req, HandlerState, RemainingData, 0, Payload) -> websocket_data(State#state{frag_state={nofin, Opcode, - <<Payloads/binary, Payload/binary>>}}, Req, HandlerState, - RemainingData); -%% Last frame of a fragmented message unmasked. Dispatch to handler. -websocket_dispatch(State=#state{frag_state={fin, Opcode, Payloads}}, Req, - HandlerState, RemainingData, 0, Payload) -> + << SoFar/binary, Payload/binary >>}}, Req, HandlerState, RemainingData); +%% Last continuation frame. +websocket_dispatch(State=#state{frag_state={fin, Opcode, SoFar}}, + Req, HandlerState, RemainingData, 0, Payload) -> websocket_dispatch(State#state{frag_state=undefined}, Req, HandlerState, - RemainingData, Opcode, <<Payloads/binary, Payload/binary>>); + RemainingData, Opcode, << SoFar/binary, Payload/binary >>); %% Text frame. websocket_dispatch(State, Req, HandlerState, RemainingData, 1, Payload) -> handler_call(State, Req, HandlerState, RemainingData, @@ -431,13 +501,15 @@ websocket_dispatch(State, Req, HandlerState, RemainingData, 2, Payload) -> handler_call(State, Req, HandlerState, RemainingData, websocket_handle, {binary, Payload}, fun websocket_data/4); %% Close control frame. -%% @todo Handle the optional Payload. -websocket_dispatch(State, Req, HandlerState, _RemainingData, 8, _Payload) -> - websocket_close(State, Req, HandlerState, {normal, closed}); +websocket_dispatch(State, Req, HandlerState, _RemainingData, 8, <<>>) -> + websocket_close(State, Req, HandlerState, {remote, closed}); +websocket_dispatch(State, Req, HandlerState, _RemainingData, 8, + << Code:16, Payload/bits >>) -> + websocket_close(State, Req, HandlerState, {remote, Code, Payload}); %% Ping control frame. Send a pong back and forward the ping to the handler. websocket_dispatch(State=#state{socket=Socket, transport=Transport}, Req, HandlerState, RemainingData, 9, Payload) -> - Len = hybi_payload_length(byte_size(Payload)), + Len = payload_length_to_binary(byte_size(Payload)), Transport:send(Socket, << 1:1, 0:3, 10:4, 0:1, Len/bits, Payload/binary >>), handler_call(State, Req, HandlerState, RemainingData, websocket_handle, {ping, Payload}, fun websocket_data/4); @@ -446,10 +518,12 @@ websocket_dispatch(State, Req, HandlerState, RemainingData, 10, Payload) -> handler_call(State, Req, HandlerState, RemainingData, websocket_handle, {pong, Payload}, fun websocket_data/4). --spec handler_call(#state{}, cowboy_req:req(), any(), binary(), - atom(), any(), fun()) -> closed. -handler_call(State=#state{handler=Handler, opts=Opts}, Req, HandlerState, - RemainingData, Callback, Message, NextState) -> +-spec handler_call(#state{}, Req, any(), binary(), atom(), any(), fun()) + -> {ok, Req, cowboy_middleware:env()} + | {suspend, module(), atom(), [any()]} + when Req::cowboy_req:req(). +handler_call(State=#state{handler=Handler, handler_opts=HandlerOpts}, Req, + HandlerState, RemainingData, Callback, Message, NextState) -> try Handler:Callback(Message, Req, HandlerState) of {ok, Req2, HandlerState2} -> NextState(State, Req2, HandlerState2, RemainingData); @@ -515,7 +589,7 @@ handler_call(State=#state{handler=Handler, opts=Opts}, Req, HandlerState, " for the reason ~p:~p~n** Message was ~p~n" "** Options were ~p~n** Handler state was ~p~n" "** Request was ~p~n** Stacktrace: ~p~n~n", - [Handler, Callback, 3, Class, Reason, Message, Opts, + [Handler, Callback, 3, Class, Reason, Message, HandlerOpts, HandlerState, PLReq, erlang:get_stacktrace()]), websocket_close(State, Req, HandlerState, {error, handler}) end. @@ -528,13 +602,6 @@ websocket_opcode(pong) -> 10. -spec websocket_send(frame(), #state{}) -> ok | shutdown | {error, atom()}. -%% hixie-76 text frame. -websocket_send({text, Payload}, #state{ - socket=Socket, transport=Transport, version=0}) -> - Transport:send(Socket, [0, Payload, 255]); -%% Ignore all unknown frame types for compatibility with hixie 76. -websocket_send(_Any, #state{version=0}) -> - ok; websocket_send(Type, #state{socket=Socket, transport=Transport}) when Type =:= close -> Opcode = websocket_opcode(Type), @@ -554,7 +621,7 @@ websocket_send({Type = close, StatusCode, Payload}, #state{ Len = 2 + iolist_size(Payload), %% Control packets must not be > 125 in length. true = Len =< 125, - BinLen = hybi_payload_length(Len), + BinLen = payload_length_to_binary(Len), Transport:send(Socket, [<< 1:1, 0:3, Opcode:4, 0:1, BinLen/bits, StatusCode:16 >>, Payload]), shutdown; @@ -567,7 +634,7 @@ websocket_send({Type, Payload}, #state{socket=Socket, transport=Transport}) -> true -> true end, - BinLen = hybi_payload_length(Len), + BinLen = payload_length_to_binary(Len), Transport:send(Socket, [<< 1:1, 0:3, Opcode:4, 0:1, BinLen/bits >>, Payload]). @@ -582,20 +649,32 @@ websocket_send_many([Frame|Tail], State) -> Error -> Error end. --spec websocket_close(#state{}, cowboy_req:req(), any(), {atom(), atom()}) - -> closed. -websocket_close(State=#state{socket=Socket, transport=Transport, version=0}, - Req, HandlerState, Reason) -> - Transport:send(Socket, << 255, 0 >>), - handler_terminate(State, Req, HandlerState, Reason); +-spec websocket_close(#state{}, Req, any(), + {atom(), atom()} | {remote, close_code(), binary()}) + -> {ok, Req, cowboy_middleware:env()} + when Req::cowboy_req:req(). websocket_close(State=#state{socket=Socket, transport=Transport}, Req, HandlerState, Reason) -> - Transport:send(Socket, << 1:1, 0:3, 8:4, 0:8 >>), + case Reason of + {normal, _} -> + Transport:send(Socket, << 1:1, 0:3, 8:4, 0:1, 2:7, 1000:16 >>); + {error, badframe} -> + Transport:send(Socket, << 1:1, 0:3, 8:4, 0:1, 2:7, 1002:16 >>); + {error, badencoding} -> + Transport:send(Socket, << 1:1, 0:3, 8:4, 0:1, 2:7, 1007:16 >>); + {error, handler} -> + Transport:send(Socket, << 1:1, 0:3, 8:4, 0:1, 2:7, 1011:16 >>); + {remote, closed} -> + Transport:send(Socket, << 1:1, 0:3, 8:4, 0:8 >>); + {remote, Code, _} -> + Transport:send(Socket, << 1:1, 0:3, 8:4, 0:1, 2:7, Code:16 >>) + end, handler_terminate(State, Req, HandlerState, Reason). --spec handler_terminate(#state{}, cowboy_req:req(), - any(), atom() | {atom(), atom()}) -> closed. -handler_terminate(#state{handler=Handler, opts=Opts}, +-spec handler_terminate(#state{}, Req, any(), atom() | {atom(), atom()}) + -> {ok, Req, cowboy_middleware:env()} + when Req::cowboy_req:req(). +handler_terminate(#state{env=Env, handler=Handler, handler_opts=HandlerOpts}, Req, HandlerState, TerminateReason) -> try Handler:websocket_terminate(TerminateReason, Req, HandlerState) @@ -606,35 +685,14 @@ handler_terminate(#state{handler=Handler, opts=Opts}, " for the reason ~p:~p~n** Initial reason was ~p~n" "** Options were ~p~n** Handler state was ~p~n" "** Request was ~p~n** Stacktrace: ~p~n~n", - [Handler, websocket_terminate, 3, Class, Reason, TerminateReason, Opts, - HandlerState, PLReq, erlang:get_stacktrace()]) + [Handler, websocket_terminate, 3, Class, Reason, TerminateReason, + HandlerOpts, HandlerState, PLReq, erlang:get_stacktrace()]) end, - closed. - -%% hixie-76 specific. - --spec hixie76_challenge(binary(), binary(), binary()) -> binary(). -hixie76_challenge(Key1, Key2, Key3) -> - IntKey1 = hixie76_key_to_integer(Key1), - IntKey2 = hixie76_key_to_integer(Key2), - erlang:md5(<< IntKey1:32, IntKey2:32, Key3/binary >>). - --spec hixie76_key_to_integer(binary()) -> integer(). -hixie76_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. - -%% hybi specific. - --spec hybi_challenge(binary()) -> binary(). -hybi_challenge(Key) -> - Bin = << Key/binary, "258EAFA5-E914-47DA-95CA-C5AB0DC85B11" >>, - base64:encode(crypto:sha(Bin)). + {ok, Req, [{result, closed}|Env]}. --spec hybi_payload_length(0..16#7fffffffffffffff) +-spec payload_length_to_binary(0..16#7fffffffffffffff) -> << _:7 >> | << _:23 >> | << _:71 >>. -hybi_payload_length(N) -> +payload_length_to_binary(N) -> case N of N when N =< 125 -> << N:7 >>; N when N =< 16#ffff -> << 126:7, N:16 >>; |