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author | Loïc Hoguin <[email protected]> | 2018-04-29 11:29:26 +0200 |
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committer | Loïc Hoguin <[email protected]> | 2018-04-29 17:39:48 +0200 |
commit | 84b4128d068cddc37bbb45e755044183f3e9cd97 (patch) | |
tree | 641891c28f3409f92dafad2a7ea114c290ca423a /src/cowboy_http2.erl | |
parent | 2db5ffbf842e0aeb0ae11484b8c247bbfdcf5e9e (diff) | |
download | cowboy-84b4128d068cddc37bbb45e755044183f3e9cd97.tar.gz cowboy-84b4128d068cddc37bbb45e755044183f3e9cd97.tar.bz2 cowboy-84b4128d068cddc37bbb45e755044183f3e9cd97.zip |
Receive and ignore HTTP/2 request trailers if any
This is a first step toward properly supporting request trailers.
Diffstat (limited to 'src/cowboy_http2.erl')
-rw-r--r-- | src/cowboy_http2.erl | 69 |
1 files changed, 59 insertions, 10 deletions
diff --git a/src/cowboy_http2.erl b/src/cowboy_http2.erl index 9bd1bda..bb075ed 100644 --- a/src/cowboy_http2.erl +++ b/src/cowboy_http2.erl @@ -420,14 +420,28 @@ frame(State0=#state{remote_window=ConnWindow, streams=Streams, lingering_streams frame(State, {headers, StreamID, _, _, _}) when StreamID rem 2 =:= 0 -> terminate(State, {connection_error, protocol_error, 'HEADERS frame received with even-numbered streamid. (RFC7540 5.1.1)'}); -%% HEADERS frame received on (half-)closed stream. -%% -%% We always close the connection here to avoid having to decode -%% the headers to not waste resources on non-compliant clients. -frame(State=#state{client_streamid=LastStreamID}, {headers, StreamID, _, _, _}) +%% Either a HEADERS frame received on (half-)closed stream, +%% or a HEADERS frame containing the trailers. +frame(State=#state{client_streamid=LastStreamID, streams=Streams}, + {headers, StreamID, IsFin, IsHeadFin, HeaderBlockOrFragment}) when StreamID =< LastStreamID -> - terminate(State, {connection_error, stream_closed, - 'HEADERS frame received on a stream in closed or half-closed state. (RFC7540 5.1)'}); + case lists:keyfind(StreamID, #stream.id, Streams) of + Stream = #stream{remote=nofin} when IsFin =:= fin -> + case IsHeadFin of + head_fin -> + stream_decode_trailers(State, Stream, HeaderBlockOrFragment); + head_nofin -> + State#state{parse_state={continuation, StreamID, IsFin, HeaderBlockOrFragment}} + end; + %% We always close the connection here to avoid having to decode + %% the headers to not waste resources on non-compliant clients. + #stream{remote=nofin} when IsFin =:= nofin -> + terminate(State, {connection_error, protocol_error, + 'Trailing HEADERS frame received without the END_STREAM flag set. (RFC7540 8.1, RFC7540 8.1.2.6)'}); + _ -> + terminate(State, {connection_error, stream_closed, + 'HEADERS frame received on a stream in closed or half-closed state. (RFC7540 5.1)'}) + end; %% Single HEADERS frame headers block. frame(State, {headers, StreamID, IsFin, head_fin, HeaderBlock}) -> %% @todo We probably need to validate StreamID here and in 4 next clauses. @@ -544,10 +558,17 @@ frame(State, {continuation, _, _, _}) -> terminate(State, {connection_error, protocol_error, 'CONTINUATION frames MUST be preceded by a HEADERS frame. (RFC7540 6.10)'}). -continuation_frame(State=#state{parse_state={continuation, StreamID, IsFin, HeaderBlockFragment0}}, +continuation_frame(State=#state{client_streamid=LastStreamID, streams=Streams, + parse_state={continuation, StreamID, IsFin, HeaderBlockFragment0}}, {continuation, StreamID, head_fin, HeaderBlockFragment1}) -> - stream_decode_init(State#state{parse_state=normal}, StreamID, IsFin, - << HeaderBlockFragment0/binary, HeaderBlockFragment1/binary >>); + HeaderBlock = << HeaderBlockFragment0/binary, HeaderBlockFragment1/binary >>, + case StreamID > LastStreamID of + true -> %% New stream. + stream_decode_init(State#state{parse_state=normal}, StreamID, IsFin, HeaderBlock); + false -> %% Trailers. + Stream = lists:keyfind(StreamID, #stream.id, Streams), + stream_decode_trailers(State, Stream, HeaderBlock) + end; continuation_frame(State=#state{parse_state={continuation, StreamID, IsFin, HeaderBlockFragment0}}, {continuation, StreamID, head_nofin, HeaderBlockFragment1}) -> State#state{parse_state={continuation, StreamID, IsFin, @@ -1181,6 +1202,34 @@ stream_handler_init(State=#state{opts=Opts, 'Unhandled exception in cowboy_stream:init/3.'}) end. +stream_decode_trailers(State=#state{decode_state=DecodeState0}, Stream, HeaderBlock) -> + try cow_hpack:decode(HeaderBlock, DecodeState0) of + {Headers, DecodeState} -> + stream_reject_pseudo_headers_in_trailers(State#state{decode_state=DecodeState}, + Stream#stream{remote=fin}, Headers) + catch _:_ -> + terminate(State, {connection_error, compression_error, + 'Error while trying to decode HPACK-encoded header block. (RFC7540 4.3)'}) + end. + +stream_reject_pseudo_headers_in_trailers(State, Stream=#stream{id=StreamID}, Headers) -> + case has_pseudo_header(Headers) of + false -> + %% @todo There's probably a number of regular headers forbidden too. + %% @todo Propagate trailers. + after_commands(State, Stream); + true -> + stream_reset(State, StreamID, {stream_error, protocol_error, + 'Trailer header blocks must not contain pseudo-headers. (RFC7540 8.1.2.1)'}) + end. + +has_pseudo_header([]) -> + false; +has_pseudo_header([{<<":", _/bits>>, _}|_]) -> + true; +has_pseudo_header([_|Tail]) -> + has_pseudo_header(Tail). + %% @todo Don't send an RST_STREAM if one was already sent. stream_reset(State=#state{socket=Socket, transport=Transport}, StreamID, StreamError) -> Reason = case StreamError of |