%% Copyright (c) 2016, 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).
-export([init/6]).
-export([system_continue/3]).
-export([system_terminate/4]).
-export([system_code_change/4]).
%% @todo map
-type opts() :: [{compress, boolean()}
| {env, cowboy_middleware:env()}
| {max_empty_lines, non_neg_integer()}
| {max_header_name_length, non_neg_integer()}
| {max_header_value_length, non_neg_integer()}
| {max_headers, non_neg_integer()}
| {max_keepalive, non_neg_integer()}
| {max_request_line_length, non_neg_integer()}
| {middlewares, [module()]}
| {onresponse, cowboy:onresponse_fun()}
| {timeout, timeout()}].
-export_type([opts/0]).
-record(ps_request_line, {
empty_lines = 0 :: non_neg_integer()
}).
-record(ps_header, {
method = undefined :: binary(),
path = undefined :: binary(),
qs = undefined :: binary(),
version = undefined :: cowboy:http_version(),
headers = undefined :: map() | undefined, %% @todo better type than map()
name = undefined :: binary() | undefined
}).
%% @todo We need a state where we wait for the stream process to ask for the body.
%% OR DO WE
%% In HTTP/2 we start receiving data before the body asks for it, even if optionally
%% (and by default), so we need to be able to do the same for HTTP/1.1 too. This means
%% that when we receive data (up to a certain limit, we read from the socket and decode.
%% When we reach a limit, we stop reading from the socket momentarily until the stream
%% process asks for more or the stream ends.
%% This means that we need to keep a buffer in the stream handler (until the stream
%% process asks for it). And that we need the body state to indicate how much we have
%% left to read (and stop/start reading from the socket depending on value).
-record(ps_body, {
%% @todo flow
transfer_decode_fun :: fun(), %% @todo better type
transfer_decode_state :: any() %% @todo better type
}).
-record(stream, {
%% Stream identifier.
id = undefined :: cowboy_stream:streamid(),
%% Stream handler state.
state = undefined :: any(),
%% Client HTTP version for this stream.
version = undefined :: cowboy:http_version(),
%% Commands queued.
queue = [] :: [] %% @todo better type
}).
-type stream() :: #stream{}.
-record(state, {
parent :: pid(),
ref :: ranch:ref(),
socket :: inet:socket(),
transport :: module(),
opts = #{} :: map(),
handler :: module(),
%% Remote address and port for the connection.
peer = undefined :: {inet:ip_address(), inet:port_number()},
timer = undefined :: undefined | reference(),
%% Identifier for the stream currently being read (or waiting to be received).
in_streamid = 1 :: pos_integer(),
%% Parsing state for the current stream or stream-to-be.
in_state = #ps_request_line{} :: #ps_request_line{} | #ps_header{} | #ps_body{},
%% Identifier for the stream currently being written.
%% Note that out_streamid =< in_streamid.
out_streamid = 1 :: pos_integer(),
%% Whether we finished writing data for the current stream.
out_state = wait :: wait | headers | chunked,
%% The connection will be closed after this stream.
last_streamid = undefined :: pos_integer(),
%% Currently active HTTP/1.1 streams.
streams = [] :: [stream()],
%% Children which are in the process of shutting down.
children = [] :: [{pid(), cowboy_stream:streamid(), timeout()}]
%% @todo Automatic compression. (compress option?)
%% @todo onresponse? Equivalent using streams.
}).
-include_lib("cowlib/include/cow_inline.hrl").
-include_lib("cowlib/include/cow_parse.hrl").
-spec init(pid(), ranch:ref(), inet:socket(), module(), cowboy:opts(), module()) -> ok.
init(Parent, Ref, Socket, Transport, Opts, Handler) ->
case Transport:peername(Socket) of
{ok, Peer} ->
LastStreamID = maps:get(max_keepalive, Opts, 100),
before_loop(set_request_timeout(#state{
parent=Parent, ref=Ref, socket=Socket,
transport=Transport, opts=Opts, handler=Handler,
peer=Peer, last_streamid=LastStreamID}), <<>>);
{error, Reason} ->
%% Couldn't read the peer address; connection is gone.
terminate(undefined, {socket_error, Reason, 'An error has occurred on the socket.'})
end.
%% @todo Send a response depending on in_state and whether one was already sent.
%% @todo
%% Timeouts:
%% - waiting for new request (if no stream is currently running)
%% -> request_timeout: for whole request/headers, set at init/when we set ps_request_line{} state
%% - waiting for body (if a stream requested the body to be read)
%% -> read_body_timeout: amount of time we wait without receiving any data when reading the body
%% - if we skip the body, skip only for a specific duration
%% -> skip_body_timeout: also have a skip_body_length
%% - none if we have a stream running and it didn't request the body to be read
%% - global
%% -> inactivity_timeout: max time to wait without anything happening before giving up
before_loop(State=#state{socket=Socket, transport=Transport}, Buffer) ->
%% @todo disable this when we get to the body, until the stream asks for it?
%% Perhaps have a threshold for how much we're willing to read before waiting.
Transport:setopts(Socket, [{active, once}]),
loop(State, Buffer).
loop(State=#state{parent=Parent, socket=Socket, transport=Transport,
handler=_Handler, timer=TimerRef, children=Children}, Buffer) ->
{OK, Closed, Error} = Transport:messages(),
receive
%% Socket messages.
{OK, Socket, Data} ->
parse(<< Buffer/binary, Data/binary >>, State);
{Closed, Socket} ->
terminate(State, {socket_error, closed, 'The socket has been closed.'});
{Error, Socket, Reason} ->
terminate(State, {socket_error, Reason, 'An error has occurred on the socket.'});
%% Timeouts.
{timeout, TimerRef, Reason} ->
timeout(State, Reason);
{timeout, _, _} ->
loop(State, Buffer);
%% System messages.
{'EXIT', Parent, Reason} ->
exit(Reason);
{system, From, Request} ->
sys:handle_system_msg(Request, From, Parent, ?MODULE, [], {State, Buffer});
%% Messages pertaining to a stream.
{{Pid, StreamID}, Msg} when Pid =:= self() ->
loop(info(State, StreamID, Msg), Buffer);
%% Exit signal from children.
Msg = {'EXIT', Pid, _} ->
loop(down(State, Pid, Msg), Buffer);
%% Calls from supervisor module.
{'$gen_call', {From, Tag}, which_children} ->
Workers = [{?MODULE, Pid, worker, [?MODULE]} || {Pid, _, _} <- Children],
From ! {Tag, Workers},
loop(State, Buffer);
{'$gen_call', {From, Tag}, count_children} ->
NbChildren = length(Children),
Counts = [{specs, 1}, {active, NbChildren},
{supervisors, 0}, {workers, NbChildren}],
From ! {Tag, Counts},
loop(State, Buffer);
{'$gen_call', {From, Tag}, _} ->
From ! {Tag, {error, ?MODULE}},
loop(State, Buffer);
%% Unknown messages.
Msg ->
error_logger:error_msg("Received stray message ~p.~n", [Msg]),
loop(State, Buffer)
%% @todo Configurable timeout. This should be a global inactivity timeout
%% that triggers when really nothing happens (ie something went really wrong).
after 300000 ->
terminate(State, {internal_error, timeout, 'No message or data received before timeout.'})
end.
set_request_timeout(State0=#state{opts=Opts}) ->
State = cancel_request_timeout(State0),
Timeout = maps:get(request_timeout, Opts, 5000),
TimerRef = erlang:start_timer(Timeout, self(), request_timeout),
State#state{timer=TimerRef}.
cancel_request_timeout(State=#state{timer=TimerRef}) ->
ok = case TimerRef of
undefined -> ok;
_ -> erlang:cancel_timer(TimerRef, [{async, true}, {info, false}])
end,
State#state{timer=undefined}.
%% @todo Honestly it would be much better if we didn't enable pipelining yet.
timeout(State=#state{in_state=#ps_request_line{}}, request_timeout) ->
%% @todo If other streams are running, just set the connection to be closed
%% and stop trying to read from the socket?
terminate(State, {connection_error, timeout, 'No request-line received before timeout.'});
timeout(State=#state{socket=Socket, transport=Transport, in_state=#ps_header{}}, request_timeout) ->
%% @todo If other streams are running, maybe wait for their reply before sending 408?
%% -> Definitely. Either way, stop reading from the socket and make that stream the last.
Transport:send(Socket, cow_http:response(408, 'HTTP/1.1', [])),
terminate(State, {connection_error, timeout, 'Request headers not received before timeout.'}).
%% Request-line.
parse(<<>>, State) ->
before_loop(State, <<>>);
parse(Buffer, State=#state{in_state=#ps_request_line{empty_lines=EmptyLines}}) ->
after_parse(parse_request(Buffer, State, EmptyLines));
parse(Buffer, State=#state{in_state=PS=#ps_header{headers=Headers, name=undefined}}) ->
after_parse(parse_header(Buffer,
State#state{in_state=PS#ps_header{headers=undefined}},
Headers));
parse(Buffer, State=#state{in_state=PS=#ps_header{headers=Headers, name=Name}}) ->
after_parse(parse_hd_before_value(Buffer,
State#state{in_state=PS#ps_header{headers=undefined, name=undefined}},
Headers, Name));
parse(Buffer, State=#state{in_state=#ps_body{}}) ->
%% @todo We do not want to get the body automatically if the request doesn't ask for it.
%% We may want to get bodies that are below a threshold without waiting, and buffer them
%% until the request asks, though.
%% @todo Transfer-decoding must be done here.
after_parse(parse_body(Buffer, State)).
%% @todo Don't parse if body is finished but request isn't. Let's not parallelize for now.
after_parse({request, Req=#{streamid := StreamID, headers := Headers, version := Version},
State0=#state{handler=Handler, opts=Opts, streams=Streams0}, Buffer}) ->
%% @todo Opts at the end. Maybe pass the same Opts we got?
try Handler:init(StreamID, Req, Opts) of
{Commands, StreamState} ->
Streams = [#stream{id=StreamID, state=StreamState, version=Version}|Streams0],
State = case maybe_req_close(State0, Headers, Version) of
close -> State0#state{streams=Streams, last_streamid=StreamID};
keepalive -> State0#state{streams=Streams}
end,
parse(Buffer, commands(State, StreamID, Commands))
catch Class:Reason ->
error_logger:error_msg("Exception occurred in ~s:init(~p, ~p, ~p) "
"with reason ~p:~p.",
[Handler, StreamID, Req, Opts, Class, Reason]),
%% @todo Bad value returned here. Crashes.
ok
%% @todo Status code.
% stream_reset(State, StreamID, {internal_error, {Class, Reason},
% 'Exception occurred in StreamHandler:init/10 call.'}) %% @todo Check final arity.
end;
%% Streams are sequential so the body is always about the last stream created
%% unless that stream has terminated.
after_parse({data, StreamID, IsFin, Data, State=#state{handler=Handler,
streams=Streams0=[Stream=#stream{id=StreamID, state=StreamState0}|_]}, Buffer}) ->
try Handler:data(StreamID, IsFin, Data, StreamState0) of
{Commands, StreamState} ->
Streams = lists:keyreplace(StreamID, #stream.id, Streams0,
Stream#stream{state=StreamState}),
parse(Buffer, commands(State#state{streams=Streams}, StreamID, Commands))
catch Class:Reason ->
error_logger:error_msg("Exception occurred in ~s:data(~p, ~p, ~p, ~p) with reason ~p:~p.",
[Handler, StreamID, IsFin, Data, StreamState0, Class, Reason]),
%% @todo Bad value returned here. Crashes.
ok
%% @todo
% stream_reset(State, StreamID, {internal_error, {Class, Reason},
% 'Exception occurred in StreamHandler:data/4 call.'})
end;
%% No corresponding stream, skip.
after_parse({data, _, _, _, State, Buffer}) ->
before_loop(State, Buffer);
after_parse({more, State, Buffer}) ->
before_loop(State, Buffer).
%% Request-line.
-spec parse_request(binary(), #state{}, non_neg_integer()) -> ok.
%% Empty lines must be using \r\n.
parse_request(<< $\n, _/bits >>, State, _) ->
error_terminate(400, State, {connection_error, protocol_error,
''}); %% @todo
parse_request(<< $\s, _/bits >>, State, _) ->
error_terminate(400, State, {connection_error, protocol_error,
''}); %% @todo
%% We limit the length of the Request-line to MaxLength to avoid endlessly
%% reading from the socket and eventually crashing.
parse_request(Buffer, State=#state{opts=Opts, in_streamid=InStreamID}, EmptyLines) ->
MaxLength = maps:get(max_request_line_length, Opts, 8000),
MaxEmptyLines = maps:get(max_empty_lines, Opts, 5),
case match_eol(Buffer, 0) of
nomatch when byte_size(Buffer) > MaxLength ->
error_terminate(414, State, {connection_error, limit_reached,
''}); %% @todo
nomatch ->
{more, State#state{in_state=#ps_request_line{empty_lines=EmptyLines}}, Buffer};
1 when EmptyLines =:= MaxEmptyLines ->
error_terminate(400, State, {connection_error, limit_reached,
''}); %% @todo
1 ->
<< _:16, Rest/bits >> = Buffer,
parse_request(Rest, State, EmptyLines + 1);
_ ->
case Buffer of
%% @todo * is only for server-wide OPTIONS request (RFC7230 5.3.4); tests
<< "OPTIONS * ", Rest/bits >> ->
parse_version(Rest, State, <<"OPTIONS">>, <<"*">>, <<>>);
% << "CONNECT ", Rest/bits >> ->
% parse_authority( %% @todo
%% Accept direct HTTP/2 only at the beginning of the connection.
<< "PRI * HTTP/2.0\r\n", _/bits >> when InStreamID =:= 1 ->
%% @todo Might be worth throwing to get a clean stacktrace.
http2_upgrade(State, Buffer);
_ ->
parse_method(Buffer, State, <<>>,
maps:get(max_method_length, Opts, 32))
end
end.
match_eol(<< $\n, _/bits >>, N) ->
N;
match_eol(<< _, Rest/bits >>, N) ->
match_eol(Rest, N + 1);
match_eol(_, _) ->
nomatch.
parse_method(_, State, _, 0) ->
error_terminate(501, State, {connection_error, limit_reached,
'The method name is longer than configuration allows. (RFC7230 3.1.1)'});
parse_method(<< C, Rest/bits >>, State, SoFar, Remaining) ->
case C of
$\r -> error_terminate(400, State, {connection_error, protocol_error,
''}); %% @todo
$\s -> parse_uri(Rest, State, SoFar);
_ when ?IS_TOKEN(C) -> parse_method(Rest, State, << SoFar/binary, C >>, Remaining - 1);
_ -> error_terminate(400, State, {connection_error, protocol_error,
'The method name must contain only valid token characters. (RFC7230 3.1.1)'})
end.
parse_uri(<< H, T, T, P, "://", Rest/bits >>, State, Method)
when H =:= $h orelse H =:= $H, T =:= $t orelse T =:= $T;
P =:= $p orelse P =:= $P ->
parse_uri_skip_host(Rest, State, Method);
parse_uri(<< H, T, T, P, S, "://", Rest/bits >>, State, Method)
when H =:= $h orelse H =:= $H, T =:= $t orelse T =:= $T;
P =:= $p orelse P =:= $P; S =:= $s orelse S =:= $S ->
parse_uri_skip_host(Rest, State, Method);
parse_uri(<< $/, Rest/bits >>, State, Method) ->
parse_uri_path(Rest, State, Method, << $/ >>);
parse_uri(_, State, _) ->
error_terminate(400, State, {connection_error, protocol_error,
'Invalid request-line or request-target. (RFC7230 3.1.1, RFC7230 5.3)'}).
parse_uri_skip_host(<< C, Rest/bits >>, State, Method) ->
case C of
$\r -> error_terminate(400, State, {connection_error, protocol_error,
''}); %% @todo
$/ -> parse_uri_path(Rest, State, Method, <<"/">>);
$\s -> parse_version(Rest, State, Method, <<"/">>, <<>>);
$? -> parse_uri_query(Rest, State, Method, <<"/">>, <<>>);
$# -> skip_uri_fragment(Rest, State, Method, <<"/">>, <<>>);
_ -> parse_uri_skip_host(Rest, State, Method)
end.
parse_uri_path(<< C, Rest/bits >>, State, Method, SoFar) ->
case C of
$\r -> error_terminate(400, State, {connection_error, protocol_error,
''}); %% @todo
$\s -> parse_version(Rest, State, Method, SoFar, <<>>);
$? -> parse_uri_query(Rest, State, Method, SoFar, <<>>);
$# -> skip_uri_fragment(Rest, State, Method, SoFar, <<>>);
_ -> parse_uri_path(Rest, State, Method, << SoFar/binary, C >>)
end.
parse_uri_query(<< C, Rest/bits >>, State, M, P, SoFar) ->
case C of
$\r -> error_terminate(400, State, {connection_error, protocol_error,
''}); %% @todo
$\s -> parse_version(Rest, State, M, P, SoFar);
$# -> skip_uri_fragment(Rest, State, M, P, SoFar);
_ -> parse_uri_query(Rest, State, M, P, << SoFar/binary, C >>)
end.
skip_uri_fragment(<< C, Rest/bits >>, State, M, P, Q) ->
case C of
$\r -> error_terminate(400, State, {connection_error, protocol_error,
''}); %% @todo
$\s -> parse_version(Rest, State, M, P, Q);
_ -> skip_uri_fragment(Rest, State, M, P, Q)
end.
%% @todo Calls to parse_header should update the state.
parse_version(<< "HTTP/1.1\r\n", Rest/bits >>, State, M, P, Q) ->
parse_headers(Rest, State, M, P, Q, 'HTTP/1.1');
parse_version(<< "HTTP/1.0\r\n", Rest/bits >>, State, M, P, Q) ->
parse_headers(Rest, State, M, P, Q, 'HTTP/1.0');
parse_version(<< "HTTP/1.", _, C, _/bits >>, State, _, _, _) when C =:= $\s; C =:= $\t ->
error_terminate(400, State, {connection_error, protocol_error,
'Whitespace is not allowed after the HTTP version. (RFC7230 3.1.1)'});
parse_version(<< C, _/bits >>, State, _, _, _) when C =:= $\s; C =:= $\t ->
error_terminate(400, State, {connection_error, protocol_error,
'The separator between request target and version must be a single SP.'});
parse_version(_, State, _, _, _) ->
error_terminate(505, State, {connection_error, protocol_error,
''}). %% @todo
parse_headers(Rest, State, M, P, Q, V) ->
%% @todo Figure out the parse states.
parse_header(Rest, State#state{in_state=#ps_header{
method=M, path=P, qs=Q, version=V}}, #{}).
%% Headers.
%% We need two or more bytes in the buffer to continue.
parse_header(Rest, State=#state{in_state=PS}, Headers) when byte_size(Rest) < 2 ->
{more, State#state{in_state=PS#ps_header{headers=Headers}}, Rest};
parse_header(<< $\r, $\n, Rest/bits >>, S, Headers) ->
request(Rest, S, Headers);
parse_header(Buffer, State=#state{opts=Opts, in_state=PS}, Headers) ->
MaxLength = maps:get(max_header_name_length, Opts, 64),
MaxHeaders = maps:get(max_headers, Opts, 100),
case match_colon(Buffer, 0) of
nomatch when byte_size(Buffer) > MaxLength ->
error_terminate(400, State, {connection_error, limit_reached,
''}); %% @todo
nomatch when length(Headers) >= MaxHeaders ->
error_terminate(400, State, {connection_error, limit_reached,
''}); %% @todo
nomatch ->
{more, State#state{in_state=PS#ps_header{headers=Headers}}, Buffer};
_ ->
parse_hd_name(Buffer, State, Headers, <<>>)
end.
match_colon(<< $:, _/bits >>, N) ->
N;
match_colon(<< _, Rest/bits >>, N) ->
match_colon(Rest, N + 1);
match_colon(_, _) ->
nomatch.
parse_hd_name(<< $:, Rest/bits >>, State, H, SoFar) ->
parse_hd_before_value(Rest, State, H, SoFar);
parse_hd_name(<< C, _/bits >>, State, _, <<>>) when ?IS_WS(C) ->
error_terminate(400, State, {connection_error, protocol_error,
''}); %% @todo
parse_hd_name(<< C, Rest/bits >>, State, H, SoFar) when ?IS_WS(C) ->
parse_hd_name_ws(Rest, State, H, SoFar);
parse_hd_name(<< C, Rest/bits >>, State, H, SoFar) ->
?LOWER(parse_hd_name, Rest, State, H, SoFar).
parse_hd_name_ws(<< C, Rest/bits >>, S, H, Name) ->
case C of
$\s -> parse_hd_name_ws(Rest, S, H, Name);
$\t -> parse_hd_name_ws(Rest, S, H, Name);
$: -> parse_hd_before_value(Rest, S, H, Name)
end.
parse_hd_before_value(<< $\s, Rest/bits >>, S, H, N) ->
parse_hd_before_value(Rest, S, H, N);
parse_hd_before_value(<< $\t, Rest/bits >>, S, H, N) ->
parse_hd_before_value(Rest, S, H, N);
parse_hd_before_value(Buffer, State=#state{opts=Opts, in_state=PS}, H, N) ->
MaxLength = maps:get(max_header_value_length, Opts, 4096),
case match_eol(Buffer, 0) of
nomatch when byte_size(Buffer) > MaxLength ->
error_terminate(400, State, {connection_error, limit_reached,
''}); %% @todo
nomatch ->
{more, State#state{in_state=PS#ps_header{headers=H, name=N}}, Buffer};
_ ->
parse_hd_value(Buffer, State, H, N, <<>>)
end.
parse_hd_value(<< $\r, $\n, Rest/bits >>, S, Headers0, Name, SoFar) ->
Value = clean_value_ws_end(SoFar, byte_size(SoFar) - 1),
Headers = case maps:get(Name, Headers0, undefined) of
undefined -> Headers0#{Name => Value};
%% The cookie header does not use proper HTTP header lists.
Value0 when Name =:= <<"cookie">> -> Headers0#{Name => << Value0/binary, "; ", Value/binary >>};
Value0 -> Headers0#{Name => << Value0/binary, ", ", Value/binary >>}
end,
parse_header(Rest, S, Headers);
parse_hd_value(<< C, Rest/bits >>, S, H, N, SoFar) ->
parse_hd_value(Rest, S, H, N, << SoFar/binary, C >>).
clean_value_ws_end(_, -1) ->
<<>>;
clean_value_ws_end(Value, N) ->
case binary:at(Value, N) of
$\s -> clean_value_ws_end(Value, N - 1);
$\t -> clean_value_ws_end(Value, N - 1);
_ ->
S = N + 1,
<< Value2:S/binary, _/bits >> = Value,
Value2
end.
-ifdef(TEST).
clean_value_ws_end_test_() ->
Tests = [
{<<>>, <<>>},
{<<" ">>, <<>>},
{<<"text/*;q=0.3, text/html;q=0.7, text/html;level=1, "
"text/html;level=2;q=0.4, */*;q=0.5 \t \t ">>,
<<"text/*;q=0.3, text/html;q=0.7, text/html;level=1, "
"text/html;level=2;q=0.4, */*;q=0.5">>}
],
[{V, fun() -> R = clean_value_ws_end(V, byte_size(V) - 1) end} || {V, R} <- Tests].
horse_clean_value_ws_end() ->
horse:repeat(200000,
clean_value_ws_end(
<<"text/*;q=0.3, text/html;q=0.7, text/html;level=1, "
"text/html;level=2;q=0.4, */*;q=0.5 ">>,
byte_size(<<"text/*;q=0.3, text/html;q=0.7, text/html;level=1, "
"text/html;level=2;q=0.4, */*;q=0.5 ">>) - 1)
).
-endif.
request(Buffer, State=#state{transport=Transport, in_streamid=StreamID,
in_state=#ps_header{version=Version}}, Headers) ->
case maps:get(<<"host">>, Headers, undefined) of
undefined when Version =:= 'HTTP/1.1' ->
%% @todo Might want to not close the connection on this and next one.
error_terminate(400, State, {stream_error, StreamID, protocol_error,
''}); %% @todo
undefined ->
request(Buffer, State, Headers, <<>>, default_port(Transport:secure()));
RawHost ->
try cow_http_hd:parse_host(RawHost) of
{Host, undefined} ->
request(Buffer, State, Headers, Host, default_port(Transport:secure()));
{Host, Port} ->
request(Buffer, State, Headers, Host, Port)
catch _:_ ->
error_terminate(400, State, {stream_error, StreamID, protocol_error,
''}) %% @todo
end
end.
-spec default_port(boolean()) -> 80 | 443.
default_port(true) -> 443;
default_port(_) -> 80.
%% End of request parsing.
request(Buffer, State0=#state{ref=Ref, transport=Transport, peer=Peer, in_streamid=StreamID,
in_state=#ps_header{method=Method, path=Path, qs=Qs, version=Version}},
Headers, Host, Port) ->
Scheme = case Transport:secure() of
true -> <<"https">>;
false -> <<"http">>
end,
{HasBody, BodyLength, TDecodeFun, TDecodeState} = case Headers of
#{<<"content-length">> := <<"0">>} ->
{false, 0, undefined, undefined};
#{<<"content-length">> := BinLength} ->
Length = try
cow_http_hd:parse_content_length(BinLength)
catch _:_ ->
error_terminate(400, State0, {stream_error, StreamID, protocol_error,
''}) %% @todo
%% @todo Err should terminate here...
end,
{true, Length, fun cow_http_te:stream_identity/2, {0, Length}};
%% @todo Better handling of transfer decoding.
#{<<"transfer-encoding">> := <<"chunked">>} ->
{true, undefined, fun cow_http_te:stream_chunked/2, {0, 0}};
_ ->
{false, 0, undefined, undefined}
end,
Req = #{
ref => Ref,
pid => self(),
streamid => StreamID,
peer => Peer,
method => Method,
scheme => Scheme,
host => Host,
port => Port,
%% @todo So the path component needs to be normalized.
path => Path,
qs => Qs,
version => Version,
%% We are transparently taking care of transfer-encodings so
%% the user code has no need to know about it.
headers => maps:remove(<<"transfer-encoding">>, Headers),
has_body => HasBody,
body_length => BodyLength
%% @todo multipart? keep state separate
%% meta values (cowboy_websocket, cowboy_rest)
},
case is_http2_upgrade(Headers, Version) of
false ->
State = case HasBody of
true ->
cancel_request_timeout(State0#state{in_state=#ps_body{
%% @todo Don't need length anymore?
transfer_decode_fun = TDecodeFun,
transfer_decode_state = TDecodeState
}});
false ->
set_request_timeout(State0#state{in_streamid=StreamID + 1, in_state=#ps_request_line{}})
end,
{request, Req, State, Buffer};
{true, HTTP2Settings} ->
http2_upgrade(State0, Buffer, HTTP2Settings, Req)
end.
%% HTTP/2 upgrade.
is_http2_upgrade(#{<<"connection">> := Conn, <<"upgrade">> := Upgrade,
<<"http2-settings">> := HTTP2Settings}, 'HTTP/1.1') ->
Conns = cow_http_hd:parse_connection(Conn),
case {lists:member(<<"upgrade">>, Conns), lists:member(<<"http2-settings">>, Conns)} of
{true, true} ->
Protocols = cow_http_hd:parse_upgrade(Upgrade),
case lists:member(<<"h2c">>, Protocols) of
true ->
{true, HTTP2Settings};
false ->
false
end;
_ ->
false
end;
is_http2_upgrade(_, _) ->
false.
%% Upgrade through an HTTP/1.1 request.
%% Prior knowledge upgrade, without an HTTP/1.1 request.
http2_upgrade(State=#state{parent=Parent, ref=Ref, socket=Socket, transport=Transport,
opts=Opts, handler=Handler, peer=Peer}, Buffer) ->
case Transport:secure() of
false ->
_ = cancel_request_timeout(State),
cowboy_http2:init(Parent, Ref, Socket, Transport, Opts, Handler, Peer, Buffer);
true ->
error_terminate(400, State, {connection_error, protocol_error,
'Clients that support HTTP/2 over TLS MUST use ALPN. (RFC7540 3.4)'})
end.
http2_upgrade(State=#state{parent=Parent, ref=Ref, socket=Socket, transport=Transport,
opts=Opts, handler=Handler, peer=Peer}, Buffer, HTTP2Settings, Req) ->
%% @todo
%% However if the client sent a body, we need to read the body in full
%% and if we can't do that, return a 413 response. Some options are in order.
%% Always half-closed stream coming from this side.
try cow_http_hd:parse_http2_settings(HTTP2Settings) of
Settings ->
Transport:send(Socket, cow_http:response(101, 'HTTP/1.1', maps:to_list(#{
<<"connection">> => <<"Upgrade">>,
<<"upgrade">> => <<"h2c">>
}))),
%% @todo Possibly redirect the request if it was https.
_ = cancel_request_timeout(State),
cowboy_http2:init(Parent, Ref, Socket, Transport, Opts, Handler, Peer, Buffer, Settings, Req)
catch _:_ ->
error_terminate(400, State, {connection_error, protocol_error,
'The HTTP2-Settings header contains a base64 SETTINGS payload. (RFC7540 3.2, RFC7540 3.2.1)'})
end.
%% Request body parsing.
parse_body(Buffer, State=#state{in_streamid=StreamID, in_state=
PS=#ps_body{transfer_decode_fun=TDecode, transfer_decode_state=TState0}}) ->
%% @todo Proper trailers.
case TDecode(Buffer, TState0) of
more ->
%% @todo Asks for 0 or more bytes.
{more, State, Buffer};
{more, Data, TState} ->
%% @todo Asks for 0 or more bytes.
{data, StreamID, nofin, Data, State#state{in_state=
PS#ps_body{transfer_decode_state=TState}}, <<>>};
{more, Data, _Length, TState} when is_integer(_Length) ->
%% @todo Asks for Length more bytes.
{data, StreamID, nofin, Data, State#state{in_state=
PS#ps_body{transfer_decode_state=TState}}, <<>>};
{more, Data, Rest, TState} ->
%% @todo Asks for 0 or more bytes.
{data, StreamID, nofin, Data, State#state{in_state=
PS#ps_body{transfer_decode_state=TState}}, Rest};
{done, TotalLength, Rest} ->
{data, StreamID, {fin, TotalLength}, <<>>, set_request_timeout(
State#state{in_streamid=StreamID + 1, in_state=#ps_request_line{}}), Rest};
{done, Data, TotalLength, Rest} ->
{data, StreamID, {fin, TotalLength}, Data, set_request_timeout(
State#state{in_streamid=StreamID + 1, in_state=#ps_request_line{}}), Rest}
end.
%% Message handling.
%% @todo There is a difference in behavior between HTTP/1.1 and HTTP/2
%% when an error or crash occurs after sending a 500 response. In HTTP/2
%% the error will be printed, in HTTP/1.1 the error will be ignored.
%% This is due to HTTP/1.1 disabling streams differently after both
%% requests and responses have been sent.
down(State=#state{children=Children0}, Pid, Msg) ->
case lists:keytake(Pid, 1, Children0) of
{value, {_, undefined, _}, Children} ->
State#state{children=Children};
{value, {_, StreamID, _}, Children} ->
info(State#state{children=Children}, StreamID, Msg);
false ->
error_logger:error_msg("Received EXIT signal ~p for unknown process ~p.~n", [Msg, Pid]),
State
end.
info(State=#state{handler=Handler, streams=Streams0}, StreamID, Msg) ->
case lists:keyfind(StreamID, #stream.id, Streams0) of
Stream = #stream{state=StreamState0} ->
try Handler:info(StreamID, Msg, StreamState0) of
{Commands, StreamState} ->
Streams = lists:keyreplace(StreamID, #stream.id, Streams0,
Stream#stream{state=StreamState}),
commands(State#state{streams=Streams}, StreamID, Commands)
catch Class:Reason ->
error_logger:error_msg("Exception occurred in ~s:info(~p, ~p, ~p) with reason ~p:~p.",
[Handler, StreamID, Msg, StreamState0, Class, Reason]),
ok
%% @todo
% stream_reset(State, StreamID, {internal_error, {Class, Reason},
% 'Exception occurred in StreamHandler:info/3 call.'})
end;
false ->
error_logger:error_msg("Received message ~p for unknown stream ~p.~n", [Msg, StreamID]),
State
end.
%% Commands.
commands(State, _, []) ->
State;
%% Supervise a child process.
commands(State=#state{children=Children}, StreamID, [{spawn, Pid, Shutdown}|Tail]) ->
commands(State#state{children=[{Pid, StreamID, Shutdown}|Children]}, StreamID, Tail);
%% Error handling.
commands(State, StreamID, [Error = {internal_error, _, _}|Tail]) ->
commands(stream_reset(State, StreamID, Error), StreamID, Tail);
%% Commands for a stream currently inactive.
commands(State=#state{out_streamid=Current, streams=Streams0}, StreamID, Commands)
when Current =/= StreamID ->
%% @todo We still want to handle some commands...
Stream = #stream{queue=Queue} = lists:keyfind(StreamID, #stream.id, Streams0),
Streams = lists:keyreplace(StreamID, #stream.id, Streams0,
Stream#stream{queue=Queue ++ Commands}),
State#state{streams=Streams};
%% Read the request body.
commands(State, StreamID, [{flow, _Length}|Tail]) ->
%% @todo We only read from socket if buffer is empty, otherwise
%% we decode the buffer.
%% @todo Set the body reading length to min(Length, BodyLength)
commands(State, StreamID, Tail);
%% Error responses are sent only if a response wasn't sent already.
commands(State=#state{out_state=wait}, StreamID, [{error_response, StatusCode, Headers, Body}|Tail]) ->
commands(State, StreamID, [{response, StatusCode, Headers, Body}|Tail]);
commands(State, StreamID, [{error_response, _, _, _}|Tail]) ->
commands(State, StreamID, Tail);
%% Send a full response.
%%
%% @todo Kill the stream if it sent a response when one has already been sent.
%% @todo Keep IsFin in the state.
%% @todo Same two things above apply to DATA, possibly promise too.
commands(State0=#state{socket=Socket, transport=Transport, out_state=wait, streams=Streams}, StreamID,
[{response, StatusCode, Headers0, Body}|Tail]) ->
%% @todo I'm pretty sure the last stream in the list is the one we want
%% considering all others are queued.
#stream{version=Version} = lists:keyfind(StreamID, #stream.id, Streams),
{State, Headers} = connection(State0, Headers0, StreamID, Version),
%% @todo Ensure content-length is set.
Response = cow_http:response(StatusCode, 'HTTP/1.1', headers_to_list(Headers)),
case Body of
{sendfile, O, B, P} ->
Transport:send(Socket, Response),
commands(State#state{out_state=done}, StreamID, [{sendfile, fin, O, B, P}|Tail]);
_ ->
Transport:send(Socket, [Response, Body]),
%% @todo If max number of requests, close connection.
%% @todo If IsFin, maybe skip body of current request.
maybe_terminate(State#state{out_state=done}, StreamID, Tail, fin)
end;
%% Send response headers and initiate chunked encoding.
commands(State0=#state{socket=Socket, transport=Transport, streams=Streams}, StreamID,
[{headers, StatusCode, Headers0}|Tail]) ->
%% @todo Same as above.
#stream{version=Version} = lists:keyfind(StreamID, #stream.id, Streams),
{State1, Headers1} = case Version of
'HTTP/1.1' ->
{State0, Headers0#{<<"transfer-encoding">> => <<"chunked">>}};
%% Close the connection after streaming the data to HTTP/1.0 client.
%% @todo I'm guessing we need to differentiate responses with a content-length and others.
'HTTP/1.0' ->
{State0#state{last_streamid=StreamID}, Headers0}
end,
{State, Headers} = connection(State1, Headers1, StreamID, Version),
Transport:send(Socket, cow_http:response(StatusCode, 'HTTP/1.1', headers_to_list(Headers))),
commands(State#state{out_state=chunked}, StreamID, Tail);
%% Send a response body chunk.
%%
%% @todo WINDOW_UPDATE stuff require us to buffer some data.
%% @todo We probably want to allow Data to be the {sendfile, ...} tuple also.
commands(State=#state{socket=Socket, transport=Transport, streams=Streams}, StreamID,
[{data, IsFin, Data}|Tail]) ->
%% @todo We need to kill the stream if it tries to send data before headers.
%% @todo Same as above.
case lists:keyfind(StreamID, #stream.id, Streams) of
#stream{version='HTTP/1.1'} ->
Size = iolist_size(Data),
Transport:send(Socket, [integer_to_binary(Size, 16), <<"\r\n">>, Data, <<"\r\n">>]);
#stream{version='HTTP/1.0'} ->
Transport:send(Socket, Data)
end,
maybe_terminate(State, StreamID, Tail, IsFin);
%% Send a file.
commands(State=#state{socket=Socket, transport=Transport}, StreamID,
[{sendfile, IsFin, Offset, Bytes, Path}|Tail]) ->
Transport:sendfile(Socket, Path, Offset, Bytes),
maybe_terminate(State, StreamID, Tail, IsFin);
%% Protocol takeover.
commands(State0=#state{ref=Ref, parent=Parent, socket=Socket, transport=Transport,
opts=Opts, children=Children}, StreamID,
[{switch_protocol, Headers, Protocol, InitialState}|_Tail]) ->
%% @todo This should be the last stream running otherwise we need to wait before switching.
%% @todo If there's streams opened after this one, fail instead of 101.
State = cancel_request_timeout(State0),
%% @todo When we actually do the upgrade, we only have the one stream left, plus
%% possibly some processes terminating. We need a smart strategy for handling the
%% children shutdown. We can start with brutal_kill and discarding the EXIT messages
%% received before switching to Websocket. Something better would be to let the
%% stream processes finish but that implies the Websocket module to know about
%% them and filter the messages. For now, kill them all and discard all messages
%% in the mailbox.
_ = [exit(Pid, kill) || {Pid, _, _} <- Children],
flush(),
%% Everything good, upgrade!
_ = commands(State, StreamID, [{response, 101, Headers, <<>>}]),
%% @todo This is no good because commands return a state normally and here it doesn't
%% we need to let this module go entirely. Perhaps it should be handled directly in
%% cowboy_clear/cowboy_tls? Perhaps not. We do want that Buffer.
Protocol:takeover(Parent, Ref, Socket, Transport, Opts, <<>>, InitialState);
%% Stream shutdown.
commands(State, StreamID, [stop|Tail]) ->
%% @todo Do we want to run the commands after a stop?
% commands(stream_terminate(State, StreamID, stop), StreamID, Tail).
%% @todo I think that's where we need to terminate streams.
maybe_terminate(State, StreamID, Tail, fin);
%% HTTP/1.1 does not support push; ignore.
commands(State, StreamID, [{push, _, _, _, _, _, _, _}|Tail]) ->
commands(State, StreamID, Tail).
%% The set-cookie header is special; we can only send one cookie per header.
headers_to_list(Headers0=#{<<"set-cookie">> := SetCookies}) ->
Headers1 = maps:to_list(maps:remove(<<"set-cookie">>, Headers0)),
Headers1 ++ [{<<"set-cookie">>, Value} || Value <- SetCookies];
headers_to_list(Headers) ->
maps:to_list(Headers).
flush() ->
receive _ -> flush() after 0 -> ok end.
maybe_terminate(State, StreamID, Tail, nofin) ->
commands(State, StreamID, Tail);
%% @todo In these cases I'm not sure if we should continue processing commands.
maybe_terminate(State=#state{last_streamid=StreamID}, StreamID, _Tail, fin) ->
terminate(stream_terminate(State, StreamID, normal), normal); %% @todo Reason ok?
maybe_terminate(State, StreamID, _Tail, fin) ->
stream_terminate(State, StreamID, normal).
stream_reset(State, StreamID, StreamError={internal_error, _, _}) ->
%% @todo headers
%% @todo Don't send this if there are no streams left.
% Transport:send(Socket, cow_http:response(500, 'HTTP/1.1', [
% {<<"content-length">>, <<"0">>}
% ])),
%% @todo update IsFin local
% stream_terminate(State#state{out_state=done}, StreamID, StreamError).
stream_terminate(State, StreamID, StreamError).
stream_terminate(State=#state{socket=Socket, transport=Transport, handler=Handler,
out_streamid=OutStreamID, out_state=OutState,
streams=Streams0, children=Children0}, StreamID, Reason) ->
{value, #stream{state=StreamState, version=Version}, Streams}
= lists:keytake(StreamID, #stream.id, Streams0),
_ = case OutState of
wait ->
Transport:send(Socket, cow_http:response(204, 'HTTP/1.1', []));
chunked when Version =:= 'HTTP/1.1' ->
Transport:send(Socket, <<"0\r\n\r\n">>);
_ -> %% done or Version =:= 'HTTP/1.0'
ok
end,
stream_call_terminate(StreamID, Reason, Handler, StreamState),
%% @todo initiate children shutdown
% Children = stream_terminate_children(Children0, StreamID, []),
Children = [case C of
{Pid, StreamID, Shutdown} -> {Pid, undefined, Shutdown};
_ -> C
end || C <- Children0],
%% @todo Skip the body, if any, or drop the connection if too large.
%% @todo Only do this if Current =:= StreamID.
NextOutStreamID = OutStreamID + 1,
case lists:keyfind(NextOutStreamID, #stream.id, Streams) of
false ->
%% @todo This is clearly wrong, if the stream is gone we need to check if
%% there used to be such a stream, and if there was to send an error.
State#state{out_streamid=NextOutStreamID, out_state=wait, streams=Streams, children=Children};
#stream{queue=Commands} ->
%% @todo Remove queue from the stream.
commands(State#state{out_streamid=NextOutStreamID, out_state=wait,
streams=Streams, children=Children}, NextOutStreamID, Commands)
end.
%% @todo Taken directly from _http2
stream_call_terminate(StreamID, Reason, Handler, StreamState) ->
try
Handler:terminate(StreamID, Reason, StreamState),
ok
catch Class:Reason ->
error_logger:error_msg("Exception occurred in ~s:terminate(~p, ~p, ~p) with reason ~p:~p.",
[Handler, StreamID, Reason, StreamState, Class, Reason])
end.
%stream_terminate_children([], _, Acc) ->
% Acc;
%stream_terminate_children([{Pid, StreamID}|Tail], StreamID, Acc) ->
% exit(Pid, kill),
% stream_terminate_children(Tail, StreamID, Acc);
%stream_terminate_children([Child|Tail], StreamID, Acc) ->
% stream_terminate_children(Tail, StreamID, [Child|Acc]).
%% @todo max_reqs also
maybe_req_close(_, #{<<"connection">> := Conn}, 'HTTP/1.0') ->
Conns = cow_http_hd:parse_connection(Conn),
case lists:member(<<"keep-alive">>, Conns) of
true -> keepalive;
false -> close
end;
maybe_req_close(_, _, 'HTTP/1.0') ->
close;
maybe_req_close(_, #{<<"connection">> := Conn}, 'HTTP/1.1') ->
case connection_hd_is_close(Conn) of
true -> close;
false -> keepalive
end;
maybe_req_close(_State, _, _) ->
keepalive.
connection(State=#state{last_streamid=StreamID}, Headers=#{<<"connection">> := Conn}, StreamID, _) ->
case connection_hd_is_close(Conn) of
true -> {State, Headers};
%% @todo Here we need to remove keep-alive and add close, not just add close.
false -> {State, Headers#{<<"connection">> => [<<"close, ">>, Conn]}}
end;
connection(State=#state{last_streamid=StreamID}, Headers, StreamID, _) ->
{State, Headers#{<<"connection">> => <<"close">>}};
connection(State, Headers=#{<<"connection">> := Conn}, StreamID, _) ->
case connection_hd_is_close(Conn) of
true -> {State#state{last_streamid=StreamID}, Headers};
%% @todo Here we need to set keep-alive only if it wasn't set before.
false -> {State, Headers}
end;
connection(State, Headers, _, 'HTTP/1.0') ->
{State, Headers#{<<"connection">> => <<"keep-alive">>}};
connection(State, Headers, _, _) ->
{State, Headers}.
connection_hd_is_close(Conn) ->
Conns = cow_http_hd:parse_connection(iolist_to_binary(Conn)),
lists:member(<<"close">>, Conns).
error_terminate(StatusCode, State=#state{socket=Socket, transport=Transport}, Reason) ->
Transport:send(Socket, cow_http:response(StatusCode, 'HTTP/1.1', [
{<<"content-length">>, <<"0">>}
])),
terminate(State, Reason).
terminate(_State, _Reason) ->
exit(normal). %% @todo
%% System callbacks.
-spec system_continue(_, _, {#state{}, binary()}) -> ok.
system_continue(_, _, {State, Buffer}) ->
loop(State, Buffer).
-spec system_terminate(any(), _, _, _) -> no_return().
system_terminate(Reason, _, _, _) ->
exit(Reason).
-spec system_code_change(Misc, _, _, _) -> {ok, Misc} when Misc::{#state{}, binary()}.
system_code_change(Misc, _, _, _) ->
{ok, Misc}.
