%%% @doc Connect-UDP-Bind client session for h2 / h3
%%% (draft-ietf-masque-connect-udp-listen-11). Sibling of
%%% `masque_client_session' / `masque_ip_client_session'; one module
%%% serves both transports by dispatching on a `transport' field.
%%%
%%% Public API surfaced via `masque':
%%%
%%% <ul>
%%% <li>`masque:bind_connect/3' opens the tunnel.</li>
%%% <li>`masque:send_to/3' sends a UDP payload to a peer.</li>
%%% <li>`masque:assign_compression/2',
%%% `masque:open_uncompressed_context/1',
%%% `masque:close_compression/2' drive the compression-table
%%% lifecycle.</li>
%%% <li>`masque:proxy_public_address/1' reads the parsed
%%% `Proxy-Public-Address' list.</li>
%%% </ul>
%%%
%%% Owner messages (sent to the `owner' pid passed in opts):
%%%
%%% <ul>
%%% <li>`{masque_bind_packet, Sess, {IP, Port}, UdpPayload}'</li>
%%% <li>`{masque_compression_assigned, Sess, ContextId, Peer}'</li>
%%% <li>`{masque_compression_acked, Sess, ContextId}'</li>
%%% <li>`{masque_compression_closed, Sess, ContextId}'</li>
%%% <li>`{masque_closed, Sess, Reason}'</li>
%%% </ul>
-module(masque_udp_bind_client_session).
-behaviour(gen_statem).
-export([start_link/3, start/3, stop/1, info/1]).
-export([send_to/3, recv/2, set_mode/2]).
-export([assign_compression/2, open_uncompressed_context/1,
close_compression/2, proxy_public_address/1]).
-export([send_capsule/3]).
-export([init/1, callback_mode/0, terminate/3, code_change/4]).
-export([connecting/3, open/3, closing/3]).
-include("masque.hrl").
-include("masque_udp_bind.hrl").
-dialyzer({nowarn_function, [do_connect/2, build_authority/2]}).
-record(data, {
owner :: pid(),
owner_ref :: reference(),
proxy_host :: binary(),
proxy_port :: inet:port_number(),
template :: masque_uri_template:template(),
bind_target :: unscoped | {Host :: binary(), Port :: 1..65535},
bind_scope :: scoped | unscoped,
transport :: h2 | h3,
conn :: pid() | undefined,
stream_id :: non_neg_integer() | undefined,
handshake_from :: gen_statem:from() | undefined,
timeout_ref :: reference() | undefined,
mode :: message | queue,
rx_buf :: queue:queue({inet:ip_address(),
inet:port_number(), binary()}),
rx_waiters :: queue:queue({gen_statem:from(), reference()}),
cap_buf = <<>> :: binary(),
max_cap :: pos_integer(),
extra_headers = []:: [{binary(), binary()}],
public_addresses :: [{inet:ip_address(), inet:port_number()}],
own_table :: masque_compression_table:state() | undefined,
peer_table :: masque_compression_table:state() | undefined
}).
-define(CLIENT_ROLE, client).
%%====================================================================
%% Public API
%%====================================================================
%% Target shape:
%% unscoped - bind socket can talk to any peer the
%% proxy's policy allows.
%% {Host :: binary(), Port :: 1..65535}
%% - scoped bind: proxy enforces the peer.
start_link(Target, Opts, Owner) ->
gen_statem:start_link(?MODULE, {Target, Opts, Owner}, []).
start(Target, Opts, Owner) ->
gen_statem:start(?MODULE, {Target, Opts, Owner}, []).
stop(Pid) -> gen_statem:call(Pid, stop, 5000).
info(Pid) -> gen_statem:call(Pid, info, 1000).
send_to(Pid, {IP, Port}, Bytes)
when is_binary(Bytes),
is_integer(Port), Port >= 0, Port =< 65535 ->
gen_statem:call(Pid, {send_to, {IP, Port}, Bytes}).
recv(Pid, Timeout) ->
gen_statem:call(Pid, {recv, Timeout}, Timeout + 500).
set_mode(Pid, Mode) when Mode =:= message; Mode =:= queue ->
gen_statem:call(Pid, {set_mode, Mode}).
assign_compression(Pid, Peer) ->
gen_statem:call(Pid, {assign_compression, Peer}).
open_uncompressed_context(Pid) ->
gen_statem:call(Pid, open_uncompressed_context).
close_compression(Pid, ContextId) ->
gen_statem:call(Pid, {close_compression, ContextId}).
proxy_public_address(Pid) ->
gen_statem:call(Pid, proxy_public_address).
send_capsule(Pid, Type, Value) ->
gen_statem:call(Pid, {send_capsule, Type, Value}).
%%====================================================================
%% gen_statem
%%====================================================================
callback_mode() -> state_functions.
init({Target, Opts, Owner}) ->
process_flag(trap_exit, true),
{ProxyHost, ProxyPort} = maps:get(proxy, Opts),
MRef = erlang:monitor(process, Owner),
Mode = maps:get(mode, Opts, message),
Transport = maps:get(transport, Opts, h3),
MaxCap = maps:get(max_capsule_size, Opts,
?MASQUE_DEFAULT_MAX_CAPSULE_SIZE),
Template = build_template(Opts, ProxyHost, ProxyPort),
Scope = case Target of
unscoped -> unscoped;
{_,_} -> scoped
end,
Data = #data{
owner = Owner,
owner_ref = MRef,
proxy_host = to_bin(ProxyHost),
proxy_port = ProxyPort,
template = Template,
bind_target = Target,
bind_scope = Scope,
transport = Transport,
mode = Mode,
rx_buf = queue:new(),
rx_waiters = queue:new(),
max_cap = MaxCap,
extra_headers = maps:get(request_headers, Opts, []),
public_addresses = []
},
{ok, connecting, Data,
[{next_event, internal, {do_handshake, Opts}}]}.
build_template(Opts, ProxyHost, ProxyPort) ->
case maps:find(uri_template, Opts) of
{ok, Raw} ->
case masque_uri_template:parse_absolute(Raw) of
{ok, T} -> T;
{error, _} -> erlang:error(bad_template)
end;
error ->
Authority = build_authority(to_bin(ProxyHost), ProxyPort),
Raw = <<"https://", Authority/binary,
?MASQUE_DEFAULT_URI_TEMPLATE/binary>>,
{ok, T} = masque_uri_template:parse_absolute(Raw),
T
end.
%%====================================================================
%% State: connecting
%%====================================================================
connecting(internal, {do_handshake, Opts}, Data) ->
case do_connect(Data, Opts) of
{ok, Conn, StreamId} ->
Timeout = maps:get(timeout, Opts, 5000),
TRef = erlang:start_timer(Timeout, self(), handshake_timeout),
{keep_state,
Data#data{conn = Conn, stream_id = StreamId,
timeout_ref = TRef}};
{error, Reason} ->
{stop, {handshake_failed, Reason}}
end;
connecting({call, From}, handshake_await, Data) ->
{keep_state, Data#data{handshake_from = From}};
connecting({call, From}, _Other, Data) ->
%% No outbound API works before the handshake completes.
{keep_state, Data, [{reply, From, {error, not_ready}}]};
connecting(info, {Tag, _Conn, {response, StreamId, Status, Headers}},
#data{stream_id = StreamId} = Data)
when Tag =:= quic_h3; Tag =:= h2 ->
cancel_timer(Data#data.timeout_ref),
case Status of
S when S >= 200, S < 300 ->
case validate_response(Headers) of
{ok, Addrs} ->
Families = lists:usort([family_of(IP)
|| {IP, _} <- Addrs]),
TableOpts = #{advertised_families => Families},
Data1 = Data#data{
timeout_ref = undefined,
handshake_from = undefined,
public_addresses = Addrs,
own_table = masque_compression_table:new_own(
?CLIENT_ROLE, TableOpts),
peer_table = masque_compression_table:new_peer(
?CLIENT_ROLE, TableOpts)},
reply_handshake(Data, ok),
{next_state, open, Data1};
{error, Reason} ->
reply_handshake(Data, {error, Reason}),
{stop, {handshake_failed, Reason}}
end;
_ ->
reply_handshake(Data, {error, {bad_status, Status}}),
{stop, {handshake_failed, {bad_status, Status}}}
end;
connecting(info, {timeout, TRef, handshake_timeout},
#data{timeout_ref = TRef} = Data) ->
reply_handshake(Data, {error, handshake_timeout}),
{stop, handshake_timeout, Data};
connecting(info, {'DOWN', Ref, process, _, _},
#data{owner_ref = Ref}) ->
{stop, owner_gone};
connecting(info, _Msg, Data) ->
{keep_state, Data}.
%%====================================================================
%% State: open
%%====================================================================
open({call, From}, handshake_await, Data) ->
{keep_state, Data, [{reply, From, ok}]};
open({call, From}, info, Data) ->
{keep_state, Data,
[{reply, From, session_info(Data, open)}]};
open({call, From}, {send_to, Peer, Bytes}, Data) ->
{Reply, Data1} = handle_send_to(Peer, Bytes, Data),
{keep_state, Data1, [{reply, From, Reply}]};
open({call, From}, {recv, Timeout}, Data) ->
handle_recv_call(From, Timeout, Data);
open({call, From}, {set_mode, Mode}, Data) ->
{keep_state, Data#data{mode = Mode}, [{reply, From, ok}]};
open({call, From}, {assign_compression, {IP, Port}}, Data) ->
handle_assign_compression(From, {IP, Port}, Data);
open({call, From}, open_uncompressed_context, Data) ->
handle_open_uncompressed_context(From, Data);
open({call, From}, {close_compression, Id}, Data) ->
handle_close_compression(From, Id, Data);
open({call, From}, proxy_public_address, Data) ->
{keep_state, Data,
[{reply, From, {ok, Data#data.public_addresses}}]};
open({call, From}, {send_capsule, Type, Value}, Data) ->
Bytes = iolist_to_binary(masque_capsule:encode(Type, Value)),
Reply = transport_send_data(Data, Bytes, false),
{keep_state, Data, [{reply, From, Reply}]};
open({call, From}, stop, Data) ->
{next_state, closing, Data,
[{reply, From, ok},
{next_event, internal, do_close}]};
open(info, {h2_datagram, _Conn, StreamId, Payload},
#data{transport = h2, stream_id = StreamId} = Data) ->
{keep_state, handle_inbound_datagram(Payload, Data)};
open(info, {quic_h3, _Conn, {datagram, StreamId, Payload}},
#data{transport = h3, stream_id = StreamId} = Data) ->
{keep_state, handle_inbound_datagram(Payload, Data)};
open(info, {Tag, _Conn, {data, StreamId, Bytes, _Fin}},
#data{stream_id = StreamId, cap_buf = Buf,
max_cap = Max} = Data)
when Tag =:= quic_h3; Tag =:= h2 ->
New = <<Buf/binary, Bytes/binary>>,
case byte_size(New) > Max of
true -> {stop, capsule_buffer_overflow};
false -> drain_capsules(New, Data)
end;
open(info, {Tag, _Conn, {reset, StreamId, _Code}},
#data{stream_id = StreamId})
when Tag =:= quic_h3; Tag =:= h2 ->
{stop, peer_reset};
open(info, {Tag, _Conn, closed}, _Data) when Tag =:= h2; Tag =:= quic_h3 ->
{stop, peer_closed};
open(info, {timeout, TRef, {recv_timeout, From}}, Data) ->
{keep_state, drop_waiter(TRef, From, Data)};
open(info, {'DOWN', Ref, process, _, _},
#data{owner_ref = Ref} = Data) ->
{next_state, closing, Data, [{next_event, internal, do_close}]};
open(info, _Msg, Data) ->
{keep_state, Data}.
%%====================================================================
%% State: closing
%%====================================================================
closing(internal, do_close, #data{transport = h3, conn = Conn,
stream_id = StreamId} = Data) ->
_ = (try quic_h3:send_data(Conn, StreamId, <<>>, true) catch _:_ -> ok end),
{stop, normal, Data};
closing(internal, do_close, #data{transport = h2, conn = Conn,
stream_id = StreamId} = Data) ->
_ = (try h2:send_data(Conn, StreamId, <<>>, true) catch _:_ -> ok end),
{stop, normal, Data};
closing(_, _, Data) ->
{keep_state, Data}.
%%====================================================================
%% terminate / code_change
%%====================================================================
terminate(Reason, _State, #data{owner = Owner, mode = message}) ->
Owner ! {masque_closed, self(), Reason},
ok;
terminate(_Reason, _State, _Data) ->
ok.
code_change(_OldVsn, State, Data, _Extra) ->
{ok, State, Data}.
%%====================================================================
%% Send path
%%====================================================================
handle_send_to({IP, Port}, Bytes, Data) ->
Tuple = {family_of(IP), IP, Port},
case masque_compression_table:lookup_by_tuple(
Data#data.own_table, Tuple) of
{ok, #compression_entry{state = installed,
ip_version = 0}} ->
send_uncompressed(Tuple, Bytes, Data);
{ok, #compression_entry{state = installed, context_id = Id,
ip_version = V}}
when V =:= 4; V =:= 6 ->
send_compressed_inline(Id, Bytes, Data);
_ ->
try_uncompressed_fallback(Tuple, Bytes, Data)
end.
try_uncompressed_fallback(Tuple, Bytes, Data) ->
case find_peer_uncompressed(Data#data.peer_table) of
{ok, Id} ->
case masque_udp_bind_payload:encode_uncompressed(
Tuple, Bytes, advertised_families(Data)) of
{ok, Inner} ->
{ok, send_datagram(Id, Inner, Data)};
{error, _} = E ->
{E, Data}
end;
not_found ->
{{error, no_compression_context}, Data}
end.
find_peer_uncompressed(Table) ->
case [E || E <- masque_compression_table:entries(Table),
E#compression_entry.ip_version =:= 0] of
[#compression_entry{context_id = Id} | _] -> {ok, Id};
[] -> not_found
end.
send_uncompressed(Tuple, Bytes, Data) ->
case find_own_uncompressed(Data#data.own_table) of
{ok, Id} ->
case masque_udp_bind_payload:encode_uncompressed(
Tuple, Bytes, advertised_families(Data)) of
{ok, Inner} ->
{ok, send_datagram(Id, Inner, Data)};
{error, _} = E ->
{E, Data}
end;
not_found ->
{{error, no_uncompressed_context}, Data}
end.
find_own_uncompressed(Table) ->
case [E || E <- masque_compression_table:entries(Table),
E#compression_entry.ip_version =:= 0,
E#compression_entry.state =:= installed] of
[#compression_entry{context_id = Id} | _] -> {ok, Id};
[] -> not_found
end.
send_compressed_inline(Id, Bytes, Data) ->
Inner = masque_udp_bind_payload:encode_compressed(Bytes),
{ok, send_datagram(Id, Inner, Data)}.
send_datagram(Ctx, Inner, #data{transport = h3, conn = C,
stream_id = Sid} = Data) ->
Enc = masque_datagram:encode(Ctx, Inner),
_ = quic_h3:send_datagram(C, Sid, Enc),
Data;
send_datagram(Ctx, Inner, #data{transport = h2} = Data) ->
Inner1 = iolist_to_binary(masque_datagram:encode(Ctx, Inner)),
Cap = h2_capsule:encode(datagram, Inner1),
_ = transport_send_data(Data, iolist_to_binary(Cap), false),
Data.
%%====================================================================
%% Compression API handlers
%%====================================================================
handle_assign_compression(From, {IP, Port}, Data) ->
Tuple = {family_of(IP), IP, Port},
case masque_compression_table:open_compressed(
Data#data.own_table, Tuple) of
{ok, Entry, T2} ->
Bytes = iolist_to_binary(
masque_compression_capsule:encode(
#compression_assign{
context_id = Entry#compression_entry.context_id,
ip_version = Entry#compression_entry.ip_version,
address = Entry#compression_entry.address,
port = Entry#compression_entry.port})),
_ = transport_send_data(Data, Bytes, false),
{keep_state, Data#data{own_table = T2},
[{reply, From,
{ok, Entry#compression_entry.context_id}}]};
{error, Reason} ->
{keep_state, Data, [{reply, From, {error, Reason}}]}
end.
handle_open_uncompressed_context(From, Data) ->
case masque_compression_table:open_uncompressed(
Data#data.own_table) of
{ok, Entry, T2} ->
Bytes = iolist_to_binary(
masque_compression_capsule:encode(
#compression_assign{
context_id = Entry#compression_entry.context_id,
ip_version = 0,
address = undefined,
port = undefined})),
_ = transport_send_data(Data, Bytes, false),
{keep_state, Data#data{own_table = T2},
[{reply, From,
{ok, Entry#compression_entry.context_id}}]};
{error, Reason} ->
{keep_state, Data, [{reply, From, {error, Reason}}]}
end.
handle_close_compression(From, Id, Data) ->
%% Close on whichever side owns the ID. Try the own table first.
case masque_compression_table:install_close(
Data#data.own_table, #compression_close{context_id = Id}) of
{ok, OT2} ->
_ = send_close_capsule(Id, Data),
{keep_state, Data#data{own_table = OT2},
[{reply, From, ok}]};
{error, unknown_context} ->
case masque_compression_table:install_close(
Data#data.peer_table,
#compression_close{context_id = Id}) of
{ok, PT2} ->
_ = send_close_capsule(Id, Data),
{keep_state, Data#data{peer_table = PT2},
[{reply, From, ok}]};
{error, _} = E ->
{keep_state, Data, [{reply, From, E}]}
end
end.
send_close_capsule(Id, Data) ->
Bytes = iolist_to_binary(
masque_compression_capsule:encode(
#compression_close{context_id = Id})),
transport_send_data(Data, Bytes, false).
%%====================================================================
%% Inbound datagram + capsule paths
%%====================================================================
handle_inbound_datagram(Payload, Data) ->
case masque_datagram:decode(Payload) of
{ok, {0, Inner}} ->
handle_context_zero(Inner, Data);
{ok, {Ctx, Inner}} when is_integer(Ctx), Ctx > 0 ->
handle_known_context(Ctx, Inner, Data);
{error, _} ->
Data
end.
handle_context_zero(Inner, #data{bind_scope = scoped} = Data) ->
%% Scoped bind: context-id 0 is raw UDP to the scoped peer; we
%% don't have the peer tuple in-band so we surface the bytes
%% with a `scoped' marker.
deliver_bind_packet({Data#data.bind_target, scoped}, Inner, Data);
handle_context_zero(_Inner, Data) ->
Data.
handle_known_context(Ctx, Inner, Data) ->
case masque_compression_table:lookup_by_id(Data#data.peer_table, Ctx) of
{ok, #compression_entry{ip_version = 0}} ->
case masque_udp_bind_payload:decode_uncompressed(Inner) of
{ok, {_V, IP, Port}, UdpPayload} ->
deliver_bind_packet({IP, Port}, UdpPayload, Data);
{error, _} -> Data
end;
{ok, #compression_entry{ip_version = V, address = A, port = P}}
when V =:= 4; V =:= 6 ->
deliver_bind_packet({A, P}, Inner, Data);
not_found ->
Data
end.
deliver_bind_packet(PeerOrTagged, Bytes,
#data{mode = message, owner = Owner} = Data) ->
Peer = case PeerOrTagged of
{T, scoped} -> T;
T -> T
end,
Owner ! {masque_bind_packet, self(), Peer, Bytes},
Data;
deliver_bind_packet(PeerOrTagged, Bytes,
#data{mode = queue, rx_buf = Q, rx_waiters = Ws} = Data) ->
Peer = case PeerOrTagged of
{T, scoped} -> T;
T -> T
end,
case queue:out(Ws) of
{{value, {From, TRef}}, Ws2} ->
_ = erlang:cancel_timer(TRef),
gen_statem:reply(From, {ok, Peer, Bytes}),
Data#data{rx_waiters = Ws2};
{empty, _} ->
Data#data{rx_buf = queue:in({Peer, Bytes}, Q)}
end.
drain_capsules(Buf, Data) ->
case masque_capsule:decode(Buf) of
{ok, {Type, Value, Rest}} ->
case dispatch_capsule(Type, Value, Data) of
{ok, Data2} ->
drain_capsules(Rest, Data2#data{cap_buf = <<>>});
{stop, R} ->
{stop, R, Data}
end;
{more, _} ->
{keep_state, Data#data{cap_buf = Buf}};
{error, _} ->
{stop, malformed_capsule}
end.
dispatch_capsule(?MASQUE_CAPSULE_COMPRESSION_ASSIGN, Body, Data) ->
case masque_compression_capsule:decode_assign(Body) of
{ok, A} ->
case masque_compression_table:install(Data#data.peer_table, A) of
{ok, T2} ->
Owner = Data#data.owner,
Owner ! {masque_compression_assigned, self(),
A#compression_assign.context_id,
{A#compression_assign.address,
A#compression_assign.port}},
%% Send ACK for the new mapping.
Bytes = iolist_to_binary(
masque_compression_capsule:encode(
#compression_ack{
context_id =
A#compression_assign.context_id})),
_ = transport_send_data(Data, Bytes, false),
{ok, Data#data{peer_table = T2}};
{error, _} ->
{stop, malformed_capsule}
end;
{error, _} ->
{stop, malformed_capsule}
end;
dispatch_capsule(?MASQUE_CAPSULE_COMPRESSION_ACK, Body, Data) ->
case masque_compression_capsule:decode_ack(Body) of
{ok, Ack} ->
case masque_compression_table:install_ack(
Data#data.own_table, Ack) of
{ok, T2} ->
Owner = Data#data.owner,
Owner ! {masque_compression_acked, self(),
Ack#compression_ack.context_id},
{ok, Data#data{own_table = T2}};
{error, _} ->
{stop, malformed_capsule}
end;
{error, _} ->
{stop, malformed_capsule}
end;
dispatch_capsule(?MASQUE_CAPSULE_COMPRESSION_CLOSE, Body, Data) ->
case masque_compression_capsule:decode_close(Body) of
{ok, C} ->
Id = C#compression_close.context_id,
%% Try peer table first (server-originated mapping).
case masque_compression_table:install_close(
Data#data.peer_table, C) of
{ok, T2} ->
Data#data.owner !
{masque_compression_closed, self(), Id},
{ok, Data#data{peer_table = T2}};
{error, unknown_context} ->
case masque_compression_table:install_close(
Data#data.own_table, C) of
{ok, T2} ->
Data#data.owner !
{masque_compression_closed, self(), Id},
{ok, Data#data{own_table = T2}};
{error, _} ->
{stop, malformed_capsule}
end
end;
{error, _} ->
{stop, malformed_capsule}
end;
dispatch_capsule(_Type, _Value, Data) ->
%% Unknown / unrelated capsules: silently drop per RFC 9297.
{ok, Data}.
%%====================================================================
%% Recv (queue mode)
%%====================================================================
handle_recv_call(From, Timeout, #data{rx_buf = Q,
rx_waiters = Ws} = Data) ->
case queue:out(Q) of
{{value, {Peer, Bytes}}, Q2} ->
{keep_state, Data#data{rx_buf = Q2},
[{reply, From, {ok, Peer, Bytes}}]};
{empty, _} ->
TRef = erlang:start_timer(Timeout, self(),
{recv_timeout, From}),
{keep_state,
Data#data{rx_waiters = queue:in({From, TRef}, Ws)}}
end.
drop_waiter(TRef, From, #data{rx_waiters = Ws} = Data) ->
Filtered = queue:filter(
fun({F, T}) -> not (F =:= From andalso T =:= TRef) end,
Ws),
gen_statem:reply(From, {error, timeout}),
Data#data{rx_waiters = Filtered}.
%%====================================================================
%% Handshake helpers
%%====================================================================
do_connect(#data{transport = h3} = Data, Opts) ->
SSLOpts = [{server_name_indication,
binary_to_list(Data#data.proxy_host)}
| maps:get(ssl_opts, Opts, [])],
ConnOpts = #{
transport => ssl,
ssl_opts => SSLOpts,
sync => true,
verify => maps:get(verify, Opts, verify_none),
timeout => maps:get(timeout, Opts, 5000),
settings => #{enable_connect_protocol => 1, h3_datagram => 1},
h3_datagram_enabled => true,
quic_opts => #{
alpn => maps:get(alpn, Opts, [<<"h3">>]),
max_datagram_frame_size => 65535
}
},
case quic_h3:connect(Data#data.proxy_host,
Data#data.proxy_port, ConnOpts) of
{ok, Conn} ->
ReqHeaders = request_headers(Data),
case quic_h3:request(Conn, ReqHeaders,
#{end_stream => false}) of
{ok, StreamId} -> {ok, Conn, StreamId};
{error, R} ->
_ = (try quic_h3:close(Conn) catch _:_ -> ok end),
{error, {request, R}}
end;
{error, R} ->
{error, {connect, R}}
end;
do_connect(#data{transport = h2} = Data, Opts) ->
SSLOpts = [{server_name_indication,
binary_to_list(Data#data.proxy_host)}
| maps:get(ssl_opts, Opts, [])],
ConnOpts = #{
transport => ssl,
ssl_opts => SSLOpts,
sync => true,
verify => maps:get(verify, Opts, verify_none),
timeout => maps:get(timeout, Opts, 5000),
settings => #{enable_connect_protocol => 1}
},
case h2:connect(Data#data.proxy_host,
Data#data.proxy_port, ConnOpts) of
{ok, Conn} ->
ReqHeaders = request_headers(Data),
case h2:request(Conn, ReqHeaders,
#{protocol => ?MASQUE_CONNECT_UDP_PROTOCOL}) of
{ok, StreamId} -> {ok, Conn, StreamId};
{error, R} ->
_ = (try h2:close(Conn) catch _:_ -> ok end),
{error, {request, R}}
end;
{error, R} ->
{error, {connect, R}}
end.
request_headers(#data{} = Data) ->
Path = expand_path(Data#data.bind_target),
Authority = build_authority(Data#data.proxy_host,
Data#data.proxy_port),
Base = [
{<<":method">>, <<"CONNECT">>},
{<<":protocol">>, ?MASQUE_CONNECT_UDP_PROTOCOL},
{<<":scheme">>, <<"https">>},
{<<":authority">>, Authority},
{<<":path">>, Path},
{<<"capsule-protocol">>, <<"?1">>},
masque_uri_udp_bind:format_bind_header()
],
Base ++ Data#data.extra_headers.
expand_path(unscoped) ->
masque_uri_udp_bind:expand(default_template_bin(), unscoped);
expand_path({Host, Port}) ->
masque_uri_udp_bind:expand(default_template_bin(),
{to_bin(Host), Port}).
default_template_bin() ->
<<"https://h", ?MASQUE_DEFAULT_URI_TEMPLATE/binary>>.
%%====================================================================
%% Response validation: both Connect-UDP-Bind: ?1 AND
%% Proxy-Public-Address are required per draft-11.
%%====================================================================
validate_response(Headers) ->
case masque_uri_udp_bind:parse_bind_header(Headers) of
bind ->
case masque_uri_udp_bind:parse_proxy_public_address(Headers) of
{ok, Addrs} -> {ok, Addrs};
{error, _} -> {error, missing_proxy_public_address}
end;
_ ->
{error, missing_bind_response_header}
end.
%%====================================================================
%% Misc
%%====================================================================
advertised_families(#data{public_addresses = Addrs}) ->
lists:usort([family_of(IP) || {IP, _} <- Addrs]).
family_of({_,_,_,_}) -> 4;
family_of({_,_,_,_,_,_,_,_}) -> 6.
reply_handshake(#data{handshake_from = undefined}, _Reply) -> ok;
reply_handshake(#data{handshake_from = From}, Reply) ->
gen_statem:reply(From, Reply).
cancel_timer(undefined) -> ok;
cancel_timer(Ref) -> _ = erlang:cancel_timer(Ref), ok.
session_info(#data{transport = T, bind_scope = Scope}, State) ->
#{state => State, protocol => udp_bind, transport => T,
bind => Scope}.
transport_send_data(#data{transport = h3, conn = C, stream_id = Sid},
Bytes, Fin) ->
case quic_h3:send_data(C, Sid, Bytes, Fin) of
ok -> ok;
Err -> Err
end;
transport_send_data(#data{transport = h2, conn = C, stream_id = Sid},
Bytes, _Fin) ->
case h2:send_data(C, Sid, Bytes) of
ok -> ok;
Err -> Err
end.
build_authority(Host, Port) ->
iolist_to_binary([Host, ":", integer_to_binary(Port)]).
to_bin(B) when is_binary(B) -> B;
to_bin(L) when is_list(L) -> iolist_to_binary(L).