prosody/net/websocket.lua

274 lines
8.4 KiB
Lua

-- Prosody IM
-- Copyright (C) 2012 Florian Zeitz
-- Copyright (C) 2014 Daurnimator
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--
local t_concat = table.concat;
local http = require "prosody.net.http";
local frames = require "prosody.net.websocket.frames";
local base64 = require "prosody.util.encodings".base64;
local sha1 = require "prosody.util.hashes".sha1;
local random_bytes = require "prosody.util.random".bytes;
local timer = require "prosody.util.timer";
local log = require "prosody.util.logger".init "websocket";
local close_timeout = 3; -- Seconds to wait after sending close frame until closing connection.
local websockets = {};
local websocket_listeners = {};
function websocket_listeners.ondisconnect(conn, err)
local s = websockets[conn];
if not s then return; end
websockets[conn] = nil;
if s.close_timer then
timer.stop(s.close_timer);
s.close_timer = nil;
end
s.readyState = 3;
if s.close_code == nil and s.onerror then s:onerror(err); end
if s.onclose then s:onclose(s.close_code, s.close_message or err); end
end
function websocket_listeners.ondetach(conn)
websockets[conn] = nil;
end
local function fail(s, code, reason)
log("warn", "WebSocket connection failed, closing. %d %s", code, reason);
s:close(code, reason);
s.conn:close();
return false
end
function websocket_listeners.onincoming(conn, buffer, err) -- luacheck: ignore 212/err
local s = websockets[conn];
s.readbuffer = s.readbuffer..buffer;
while true do
local frame, len = frames.parse(s.readbuffer);
if frame == nil then break end
s.readbuffer = s.readbuffer:sub(len+1);
log("debug", "Websocket received frame: opcode=%0x, %i bytes", frame.opcode, #frame.data);
-- Error cases
if frame.RSV1 or frame.RSV2 or frame.RSV3 then -- Reserved bits non zero
return fail(s, 1002, "Reserved bits not zero");
end
if frame.opcode < 0x8 then
local databuffer = s.databuffer;
if frame.opcode == 0x0 then -- Continuation frames
if not databuffer then
return fail(s, 1002, "Unexpected continuation frame");
end
databuffer[#databuffer+1] = frame.data;
elseif frame.opcode == 0x1 or frame.opcode == 0x2 then -- Text or Binary frame
if databuffer then
return fail(s, 1002, "Continuation frame expected");
end
databuffer = {type=frame.opcode, frame.data};
s.databuffer = databuffer;
else
return fail(s, 1002, "Reserved opcode");
end
if frame.FIN then
s.databuffer = nil;
if s.onmessage then
s:onmessage(t_concat(databuffer), databuffer.type);
end
end
else -- Control frame
if frame.length > 125 then -- Control frame with too much payload
return fail(s, 1002, "Payload too large");
elseif not frame.FIN then -- Fragmented control frame
return fail(s, 1002, "Fragmented control frame");
end
if frame.opcode == 0x8 then -- Close request
if frame.length == 1 then
return fail(s, 1002, "Close frame with payload, but too short for status code");
end
local status_code, message = frames.parse_close(frame.data);
if status_code == nil then
--[[ RFC 6455 7.4.1
1005 is a reserved value and MUST NOT be set as a status code in a
Close control frame by an endpoint. It is designated for use in
applications expecting a status code to indicate that no status
code was actually present.
]]
status_code = 1005
elseif status_code < 1000 then
return fail(s, 1002, "Closed with invalid status code");
elseif ((status_code > 1003 and status_code < 1007) or status_code > 1011) and status_code < 3000 then
return fail(s, 1002, "Closed with reserved status code");
end
s.close_code, s.close_message = status_code, message;
s:close(1000);
return true;
elseif frame.opcode == 0x9 then -- Ping frame
frame.opcode = 0xA;
frame.MASK = true; -- RFC 6455 6.1.5: If the data is being sent by the client, the frame(s) MUST be masked
conn:write(frames.build(frame));
elseif frame.opcode == 0xA then -- Pong frame
log("debug", "Received unexpected pong frame: %s", frame.data);
else
return fail(s, 1002, "Reserved opcode");
end
end
end
return true;
end
local websocket_methods = {};
local function close_timeout_cb(now, timerid, s) -- luacheck: ignore 212/now 212/timerid
s.close_timer = nil;
log("warn", "Close timeout waiting for server to close, closing manually.");
s.conn:close();
end
function websocket_methods:close(code, reason)
if self.readyState < 2 then
code = code or 1000;
log("debug", "closing WebSocket with code %i: %s" , code , reason);
self.readyState = 2;
local conn = self.conn;
conn:write(frames.build_close(code, reason, true));
-- Do not close socket straight away, wait for acknowledgement from server.
self.close_timer = timer.add_task(close_timeout, close_timeout_cb, self);
elseif self.readyState == 2 then
log("debug", "tried to close a closing WebSocket, closing the raw socket.");
-- Stop timer
if self.close_timer then
timer.stop(self.close_timer);
self.close_timer = nil;
end
local conn = self.conn;
conn:close();
else
log("debug", "tried to close a closed WebSocket, ignoring.");
end
end
function websocket_methods:send(data, opcode)
if self.readyState < 1 then
return nil, "WebSocket not open yet, unable to send data.";
elseif self.readyState >= 2 then
return nil, "WebSocket closed, unable to send data.";
end
if opcode == "text" or opcode == nil then
opcode = 0x1;
elseif opcode == "binary" then
opcode = 0x2;
end
local frame = {
FIN = true;
MASK = true; -- RFC 6455 6.1.5: If the data is being sent by the client, the frame(s) MUST be masked
opcode = opcode;
data = tostring(data);
};
log("debug", "WebSocket sending frame: opcode=%0x, %i bytes", frame.opcode, #frame.data);
return self.conn:write(frames.build(frame));
end
local websocket_metatable = {
__index = websocket_methods;
};
local function connect(url, ex, listeners)
ex = ex or {};
--[[RFC 6455 4.1.7:
The request MUST include a header field with the name
|Sec-WebSocket-Key|. The value of this header field MUST be a
nonce consisting of a randomly selected 16-byte value that has
been base64-encoded (see Section 4 of [RFC4648]). The nonce
MUST be selected randomly for each connection.
]]
local key = base64.encode(random_bytes(16));
-- Either a single protocol string or an array of protocol strings.
local protocol = ex.protocol;
if type(protocol) == "string" then
protocol = { protocol, [protocol] = true };
elseif type(protocol) == "table" and protocol[1] then
for _, v in ipairs(protocol) do
protocol[v] = true;
end
else
protocol = nil;
end
local headers = {
["Upgrade"] = "websocket";
["Connection"] = "Upgrade";
["Sec-WebSocket-Key"] = key;
["Sec-WebSocket-Protocol"] = protocol and t_concat(protocol, ", ");
["Sec-WebSocket-Version"] = "13";
["Sec-WebSocket-Extensions"] = ex.extensions;
}
if ex.headers then
for k,v in pairs(ex.headers) do
headers[k] = v;
end
end
local s = setmetatable({
readbuffer = "";
databuffer = nil;
conn = nil;
close_code = nil;
close_message = nil;
close_timer = nil;
readyState = 0;
protocol = nil;
url = url;
onopen = listeners.onopen;
onclose = listeners.onclose;
onmessage = listeners.onmessage;
onerror = listeners.onerror;
}, websocket_metatable);
local http_url = url:gsub("^(ws)", "http");
local http_req = http.request(http_url, { -- luacheck: ignore 211/http_req
method = "GET";
headers = headers;
sslctx = ex.sslctx;
insecure = ex.insecure;
}, function(b, c, r, http_req)
if c ~= 101
or r.headers["connection"]:lower() ~= "upgrade"
or r.headers["upgrade"] ~= "websocket"
or r.headers["sec-websocket-accept"] ~= base64.encode(sha1(key .. "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"))
or (protocol and not protocol[r.headers["sec-websocket-protocol"]])
then
s.readyState = 3;
log("warn", "WebSocket connection to %s failed: %s", url, b);
if s.onerror then s:onerror("connecting-failed"); end
return;
end
s.protocol = r.headers["sec-websocket-protocol"];
-- Take possession of socket from http
local conn = http_req.conn;
http_req.conn = nil;
s.conn = conn;
websockets[conn] = s;
conn:setlistener(websocket_listeners);
log("debug", "WebSocket connected successfully to %s", url);
s.readyState = 1;
if s.onopen then s:onopen(); end
websocket_listeners.onincoming(conn, b);
end);
return s;
end
return {
connect = connect;
};