1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
%%% Copyright (c) 2019, Sunet.
%%% See LICENSE for licensing information.
%% A remote spawns an Erlang port running the 'remote' program from
%% p11-kit.
%% Receive p11 requests from p11p_server, forward them to the remote,
%% wait for a reply. If a reply is received within a timeout period,
%% forward the reply to the requesting p11p_server. If the request
%% times out, inform the remote manager (our parent).
%% TODO: "remote" is not a great name and we shouldn't just inherit it
%% from p11p-kit. Let's use "client" or "proxy_client".
-module(p11p_remote).
-behaviour(gen_server).
%% API.
-export([start_link/4]).
-export([request/2, stop/2]).
-include("p11p_rpc.hrl").
%% Genserver callbacks.
-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2,
code_change/3]).
%% Records and types.
-record(state, {
port :: port(),
replyto :: pid() | undefined,
timer :: reference() | undefined,
token :: string(), % Token name.
msg :: p11rpc:msg() | undefined,
recv_count = 0 :: non_neg_integer(),
send_count = 0 :: non_neg_integer()
}).
%% API.
-spec start_link(atom(), string(), string(), list()) ->
{ok, pid()} | {error, term()}.
start_link(ServName, TokName, ModPath, ModEnv) ->
lager:info("~p: p11p_remote starting for ~s", [ServName, ModPath]),
gen_server:start_link({local, ServName}, ?MODULE,
[TokName, ModPath, ModEnv], []).
-spec request(pid(), p11rpc_msg()) -> {ok, non_neg_integer()}.
request(Remote, Request) ->
gen_server:call(Remote, {request, Request}).
%% Use stop/1 instead of gen_server:stop/1 if you're uncertain whether
%% Pid is alive or not. An example of when that can happen is when the
%% manager receiving a server_event about a lost client. If the server
%% process terminated on request from a remote which has timed out on
%% an rpc call, chances are that the remote has already terminated by
%% the time the manager is to act on the lost client.
stop(Pid, Reason) ->
gen_server:cast(Pid, {stop, Reason}).
%% Genserver callbacks.
init([TokName, ModPath, ModEnv]) ->
RemoteBinPath = p11p_config:remotebin_path(),
Port = open_port({spawn_executable, RemoteBinPath},
[stream,
exit_status,
{env, ModEnv},
{args, [ModPath, "-v"]} % FIXME: Remove -v
]),
lager:debug("~p: ~s: new remote port: ~p", [self(), RemoteBinPath, Port]),
lager:debug("~p: ~s: module: ~s, env: ~p", [self(), RemoteBinPath, ModPath, ModEnv]),
{ok, #state{port = Port, token = TokName}}.
handle_call({request, Request}, {FromPid, _Tag},
#state{port = Port, send_count = Sent} = S) ->
%%lager:debug("~p: sending request from ~p to remote ~p", [self(), FromPid, Port]),
D = p11p_rpc:serialise(Request),
Buf = case Sent of
0 -> <<?RPC_VERSION:8, D/binary>>;
_ -> D
end,
ok = do_send(Port, Buf),
{reply, {ok, sizeBuf}, S#state{replyto = FromPid, timer = start_timer(Port),
send_count = Sent + 1}};
handle_call(Call, _From, State) ->
lager:debug("~p: Unhandled call: ~p~n", [self(), Call]),
{reply, unhandled, State}.
handle_cast({stop, Reason}, State) ->
{stop, Reason, State};
handle_cast(Cast, State) ->
lager:debug("~p: unhandled cast: ~p~n", [self(), Cast]),
{noreply, State}.
%% Receiving the very first response from remote since it was started.
handle_info({Port, {data, Data}}, State)
when Port == State#state.port, State#state.msg == undefined ->
case hd(Data) of % First octet is RPC protocol version.
?RPC_VERSION ->
{noreply, handle_remote_data(State, p11p_rpc:new(), tl(Data))};
BadVersion ->
lager:info("~p: ~p: invalid RPC version: ~p", [self(), Port,
BadVersion]),
{noreply, State}
end;
%% Receiving more data from remote.
handle_info({Port, {data, Data}}, #state{msg = Msg} = State)
when Port == State#state.port ->
{noreply, handle_remote_data(State, Msg, Data)};
%% Remote timed out.
handle_info({timeout, Timer, Port}, #state{token = Tok, replyto = Server} = S)
when Port == S#state.port, Timer == S#state.timer ->
lager:info("~p: rpc request timed out, exiting", [self()]),
p11p_remote_manager:server_event(timeout, [Tok, Server]),
State = S#state{timer = undefined},
{stop, normal, State};
handle_info(Info, State) ->
lager:debug("~p: Unhandled info: ~p~n", [self(), Info]),
{noreply, State}.
terminate(Reason, #state{port = Port}) ->
lager:debug("~p: remote terminating with reason ~p", [self(), Reason]),
port_close(Port),
ok.
code_change(_OldVersion, State, _Extra) ->
{ok, State}.
%% Private
do_send(Port, Buf) ->
%%lager:debug("~p: sending ~B octets to remote", [self(), size(Buf)]),
%% case rand:uniform(15) of
%% 1 ->
%% lager:debug("~p: faking unresponsive remote (~p) by not sending it any.", [self(), Port]);
%% _ ->
%% port_command(Port, Buf)
%% end,
true = port_command(Port, Buf),
ok.
handle_remote_data(#state{replyto = Pid, timer = Timer, recv_count = Recv} = S,
MsgIn, DataIn) ->
case p11p_rpc:parse(MsgIn, list_to_binary(DataIn)) of
{needmore, Msg} ->
S#state{msg = Msg};
{done, Msg} ->
cancel_timer(Timer),
{ok, _BytesSent} = p11p_server:reply(Pid, Msg),
%% Saving potential data not consumed by parse/2 in new message.
S#state{msg = p11p_rpc:new(Msg#p11rpc_msg.buffer),
recv_count = Recv + 1}
end.
start_timer(Port) ->
%%lager:debug("~p: starting timer", [self()]),
erlang:start_timer(3000, self(), Port).
cancel_timer(Timer) ->
%%lager:debug("~p: canceling timer", [self()]),
erlang:cancel_timer(Timer, [{async, true}, {info, false}]).
|
