-- Copyright (C) Yichun Zhang (agentzh)
-- FIXME: this library is very rough and is currently just for testing
-- the websocket server.
local wbproto = require "resty.websocket.protocol"
local bit = require "bit"
local _recv_frame = wbproto.recv_frame
local _send_frame = wbproto.send_frame
local new_tab = wbproto.new_tab
local tcp = ngx.socket.tcp
local re_match = ngx.re.match
local encode_base64 = ngx.encode_base64
local concat = table.concat
local char = string.char
local str_find = string.find
local rand = math.random
local rshift = bit.rshift
local band = bit.band
local setmetatable = setmetatable
local type = type
local debug = ngx.config.debug
local ngx_log = ngx.log
local ngx_DEBUG = ngx.DEBUG
local assert = assert
local ssl_support = true
if not ngx.config
or not ngx.config.ngx_lua_version
or ngx.config.ngx_lua_version < 9011
then
ssl_support = false
end
local _M = new_tab(0, 13)
_M._VERSION = '0.10'
local mt = { __index = _M }
function _M.new(self, opts)
local sock, err = tcp()
if not sock then
return nil, err
end
local max_payload_len, send_unmasked, timeout
if opts then
max_payload_len = opts.max_payload_len
send_unmasked = opts.send_unmasked
timeout = opts.timeout
if timeout then
sock:settimeout(timeout)
end
end
return setmetatable({
sock = sock,
max_payload_len = max_payload_len or 65535,
send_unmasked = send_unmasked,
}, mt)
end
function _M.connect(self, uri, opts)
local sock = self.sock
if not sock then
return nil, "not initialized"
end
local m, err = re_match(uri, [[^(wss?)://([^:/]+)(?::(\d+))?(.*)]], "jo")
if not m then
if err then
return nil, "failed to match the uri: " .. err
end
return nil, "bad websocket uri"
end
local scheme = m[1]
local host = m[2]
local port = m[3]
local path = m[4]
-- ngx.say("host: ", host)
-- ngx.say("port: ", port)
if not port then
port = scheme == 'wss' and 443 or 80
end
if path == "" then
path = "/"
end
local ssl_verify, server_name, headers, proto_header, origin_header
local sock_opts = false
local client_cert, client_priv_key
if opts then
local protos = opts.protocols
if protos then
if type(protos) == "table" then
proto_header = "\r\nSec-WebSocket-Protocol: "
.. concat(protos, ",")
else
proto_header = "\r\nSec-WebSocket-Protocol: " .. protos
end
end
local origin = opts.origin
if origin then
origin_header = "\r\nOrigin: " .. origin
end
local pool = opts.pool
if pool then
sock_opts = { pool = pool }
end
client_cert = opts.client_cert
client_priv_key = opts.client_priv_key
if client_cert then
assert(client_priv_key,
"client_priv_key must be provided with client_cert")
end
if opts.ssl_verify or opts.server_name then
if not ssl_support then
return nil, "ngx_lua 0.9.11+ required for SSL sockets"
end
ssl_verify = opts.ssl_verify
server_name = opts.server_name or host
end
if opts.headers then
headers = opts.headers
if type(headers) ~= "table" then
return nil, "custom headers must be a table"
end
end
end
local ok, err
if sock_opts then
ok, err = sock:connect(host, port, sock_opts)
else
ok, err = sock:connect(host, port)
end
if not ok then
return nil, "failed to connect: " .. err
end
if scheme == "wss" then
if not ssl_support then
return nil, "ngx_lua 0.9.11+ required for SSL sockets"
end
if client_cert then
ok, err = sock:setclientcert(client_cert, client_priv_key)
if not ok then
return nil, "failed to set TLS client certificate: " .. err
end
end
ok, err = sock:sslhandshake(false, server_name, ssl_verify)
if not ok then
return nil, "ssl handshake failed: " .. err
end
end
-- check for connections from pool:
local count, err = sock:getreusedtimes()
if not count then
return nil, "failed to get reused times: " .. err
end
if count > 0 then
-- being a reused connection (must have done handshake)
return 1
end
local custom_headers
if headers then
custom_headers = concat(headers, "\r\n")
custom_headers = "\r\n" .. custom_headers
end
-- do the websocket handshake:
local bytes = char(rand(256) - 1, rand(256) - 1, rand(256) - 1,
rand(256) - 1, rand(256) - 1, rand(256) - 1,
rand(256) - 1, rand(256) - 1, rand(256) - 1,
rand(256) - 1, rand(256) - 1, rand(256) - 1,
rand(256) - 1, rand(256) - 1, rand(256) - 1,
rand(256) - 1)
local key = encode_base64(bytes)
local req = "GET " .. path .. " HTTP/1.1\r\nUpgrade: websocket\r\nHost: "
.. host .. ":" .. port
.. "\r\nSec-WebSocket-Key: " .. key
.. (proto_header or "")
.. "\r\nSec-WebSocket-Version: 13"
.. (origin_header or "")
.. "\r\nConnection: Upgrade"
.. (custom_headers or "")
.. "\r\n\r\n"
local bytes, err = sock:send(req)
if not bytes then
return nil, "failed to send the handshake request: " .. err
end
local header_reader = sock:receiveuntil("\r\n\r\n")
-- FIXME: check for too big response headers
local header, err, partial = header_reader()
if not header then
return nil, "failed to receive response header: " .. err
end
-- error("header: " .. header)
-- FIXME: verify the response headers
m, err = re_match(header, [[^\s*HTTP/1\.1\s+]], "jo")
if not m then
return nil, "bad HTTP response status line: " .. header
end
return 1
end
function _M.set_timeout(self, time)
local sock = self.sock
if not sock then
return nil, nil, "not initialized yet"
end
return sock:settimeout(time)
end
function _M.recv_frame(self)
if self.fatal then
return nil, nil, "fatal error already happened"
end
local sock = self.sock
if not sock then
return nil, nil, "not initialized yet"
end
local data, typ, err = _recv_frame(sock, self.max_payload_len, false)
if not data and not str_find(err, ": timeout", 1, true) then
self.fatal = true
end
return data, typ, err
end
local function send_frame(self, fin, opcode, payload)
if self.fatal then
return nil, "fatal error already happened"
end
if self.closed then
return nil, "already closed"
end
local sock = self.sock
if not sock then
return nil, "not initialized yet"
end
local bytes, err = _send_frame(sock, fin, opcode, payload,
self.max_payload_len,
not self.send_unmasked)
if not bytes then
self.fatal = true
end
return bytes, err
end
_M.send_frame = send_frame
function _M.send_text(self, data)
return send_frame(self, true, 0x1, data)
end
function _M.send_binary(self, data)
return send_frame(self, true, 0x2, data)
end
local function send_close(self, code, msg)
local payload
if code then
if type(code) ~= "number" or code > 0x7fff then
return nil, "bad status code"
end
payload = char(band(rshift(code, 8), 0xff), band(code, 0xff))
.. (msg or "")
end
if debug then
ngx_log(ngx_DEBUG, "sending the close frame")
end
local bytes, err = send_frame(self, true, 0x8, payload)
if not bytes then
self.fatal = true
end
self.closed = true
return bytes, err
end
_M.send_close = send_close
function _M.send_ping(self, data)
return send_frame(self, true, 0x9, data)
end
function _M.send_pong(self, data)
return send_frame(self, true, 0xa, data)
end
function _M.close(self)
if self.fatal then
return nil, "fatal error already happened"
end
local sock = self.sock
if not sock then
return nil, "not initialized"
end
if not self.closed then
local bytes, err = send_close(self)
if not bytes then
return nil, "failed to send close frame: " .. err
end
end
return sock:close()
end
function _M.set_keepalive(self, ...)
local sock = self.sock
if not sock then
return nil, "not initialized"
end
return sock:setkeepalive(...)
end
return _M