diff options
Diffstat (limited to 'net/server_epoll.lua')
| -rw-r--r-- | net/server_epoll.lua | 808 |
1 files changed, 808 insertions, 0 deletions
diff --git a/net/server_epoll.lua b/net/server_epoll.lua new file mode 100644 index 00000000..ecb72a00 --- /dev/null +++ b/net/server_epoll.lua @@ -0,0 +1,808 @@ +-- Prosody IM +-- Copyright (C) 2016-2018 Kim Alvefur +-- +-- This project is MIT/X11 licensed. Please see the +-- COPYING file in the source package for more information. +-- + + +local t_sort = table.sort; +local t_insert = table.insert; +local t_remove = table.remove; +local t_concat = table.concat; +local setmetatable = setmetatable; +local tostring = tostring; +local pcall = pcall; +local type = type; +local next = next; +local pairs = pairs; +local log = require "util.logger".init("server_epoll"); +local socket = require "socket"; +local luasec = require "ssl"; +local gettime = require "util.time".now; +local createtable = require "util.table".create; +local inet = require "util.net"; +local inet_pton = inet.pton; +local _SOCKETINVALID = socket._SOCKETINVALID or -1; + +local poller = require "util.poll" +local EEXIST = poller.EEXIST; +local ENOENT = poller.ENOENT; + +local poll = assert(poller.new()); + +local _ENV = nil; +-- luacheck: std none + +local default_config = { __index = { + -- If a connection is silent for this long, close it unless onreadtimeout says not to + read_timeout = 14 * 60; + + -- How long to wait for a socket to become writable after queuing data to send + write_timeout = 60; + + -- Some number possibly influencing how many pending connections can be accepted + tcp_backlog = 128; + + -- If accepting a new incoming connection fails, wait this long before trying again + accept_retry_interval = 10; + + -- If there is still more data to read from LuaSocktes buffer, wait this long and read again + read_retry_delay = 1e-06; + + -- Size of chunks to read from sockets + read_size = 8192; + + -- Timeout used during between steps in TLS handshakes + handshake_timeout = 60; + + -- Maximum and minimum amount of time to sleep waiting for events (adjusted for pending timers) + max_wait = 86400; + min_wait = 1e-06; +}}; +local cfg = default_config.__index; + +local fds = createtable(10, 0); -- FD -> conn + +-- Timer and scheduling -- + +local timers = {}; + +local function noop() end +local function closetimer(t) + t[1] = 0; + t[2] = noop; +end + +-- Set to true when timers have changed +local resort_timers = false; + +-- Add absolute timer +local function at(time, f) + local timer = { time, f, close = closetimer }; + t_insert(timers, timer); + resort_timers = true; + return timer; +end + +-- Add relative timer +local function addtimer(timeout, f) + return at(gettime() + timeout, f); +end + +-- Run callbacks of expired timers +-- Return time until next timeout +local function runtimers(next_delay, min_wait) + -- Any timers at all? + if not timers[1] then + return next_delay; + end + + if resort_timers then + -- Sort earliest timers to the end + t_sort(timers, function (a, b) return a[1] > b[1]; end); + resort_timers = false; + end + + -- Iterate from the end and remove completed timers + for i = #timers, 1, -1 do + local timer = timers[i]; + local t, f = timer[1], timer[2]; + -- Get time for every iteration to increase accuracy + local now = gettime(); + if t > now then + -- This timer should not fire yet + local diff = t - now; + if diff < next_delay then + next_delay = diff; + end + break; + end + local new_timeout = f(now); + if new_timeout then + -- Schedule for 'delay' from the time actually scheduled, + -- not from now, in order to prevent timer drift. + timer[1] = t + new_timeout; + resort_timers = true; + else + t_remove(timers, i); + end + end + + if resort_timers or next_delay < min_wait then + -- Timers may be added from within a timer callback. + -- Those would not be considered for next_delay, + -- and we might sleep for too long, so instead + -- we return a shorter timeout so we can + -- properly sort all new timers. + next_delay = min_wait; + end + + return next_delay; +end + +-- Socket handler interface + +local interface = {}; +local interface_mt = { __index = interface }; + +function interface_mt:__tostring() + if self.sockname and self.peername then + return ("FD %d (%s, %d, %s, %d)"):format(self:getfd(), self.peername, self.peerport, self.sockname, self.sockport); + elseif self.sockname or self.peername then + return ("FD %d (%s, %d)"):format(self:getfd(), self.sockname or self.peername, self.sockport or self.peerport); + end + return ("FD %d"):format(self:getfd()); +end + +-- Replace the listener and tell the old one +function interface:setlistener(listeners, data) + self:on("detach"); + self.listeners = listeners; + self:on("attach", data); +end + +-- Call a listener callback +function interface:on(what, ...) + if not self.listeners then + log("error", "%s has no listeners", self); + return; + end + local listener = self.listeners["on"..what]; + if not listener then + -- log("debug", "Missing listener 'on%s'", what); -- uncomment for development and debugging + return; + end + local ok, err = pcall(listener, self, ...); + if not ok then + log("error", "Error calling on%s: %s", what, err); + end + return err; +end + +-- Return the file descriptor number +function interface:getfd() + if self.conn then + return self.conn:getfd(); + end + return _SOCKETINVALID; +end + +function interface:server() + return self._server or self; +end + +-- Get IP address +function interface:ip() + return self.peername or self.sockname; +end + +-- Get a port number, doesn't matter which +function interface:port() + return self.sockport or self.peerport; +end + +-- Get local port number +function interface:clientport() + return self.sockport; +end + +-- Get remote port +function interface:serverport() + if self.sockport then + return self.sockport; + elseif self._server then + self._server:port(); + end +end + +-- Return underlying socket +function interface:socket() + return self.conn; +end + +function interface:set_mode(new_mode) + self.read_size = new_mode; +end + +function interface:setoption(k, v) + -- LuaSec doesn't expose setoption :( + if self.conn.setoption then + self.conn:setoption(k, v); + end +end + +-- Timeout for detecting dead or idle sockets +function interface:setreadtimeout(t) + if t == false then + if self._readtimeout then + self._readtimeout:close(); + self._readtimeout = nil; + end + return + end + t = t or cfg.read_timeout; + if self._readtimeout then + self._readtimeout[1] = gettime() + t; + resort_timers = true; + else + self._readtimeout = addtimer(t, function () + if self:on("readtimeout") then + return cfg.read_timeout; + else + self:on("disconnect", "read timeout"); + self:destroy(); + end + end); + end +end + +-- Timeout for detecting dead sockets +function interface:setwritetimeout(t) + if t == false then + if self._writetimeout then + self._writetimeout:close(); + self._writetimeout = nil; + end + return + end + t = t or cfg.write_timeout; + if self._writetimeout then + self._writetimeout[1] = gettime() + t; + resort_timers = true; + else + self._writetimeout = addtimer(t, function () + self:on("disconnect", "write timeout"); + self:destroy(); + end); + end +end + +function interface:add(r, w) + local fd = self:getfd(); + if fd < 0 then + return nil, "invalid fd"; + end + if r == nil then r = self._wantread; end + if w == nil then w = self._wantwrite; end + local ok, err, errno = poll:add(fd, r, w); + if not ok then + if errno == EEXIST then + log("debug", "%s already registered!", self); + return self:set(r, w); -- So try to change its flags + end + log("error", "Could not register %s: %s(%d)", self, err, errno); + return ok, err; + end + self._wantread, self._wantwrite = r, w; + fds[fd] = self; + log("debug", "Watching %s", self); + return true; +end + +function interface:set(r, w) + local fd = self:getfd(); + if fd < 0 then + return nil, "invalid fd"; + end + if r == nil then r = self._wantread; end + if w == nil then w = self._wantwrite; end + local ok, err, errno = poll:set(fd, r, w); + if not ok then + log("error", "Could not update poller state %s: %s(%d)", self, err, errno); + return ok, err; + end + self._wantread, self._wantwrite = r, w; + return true; +end + +function interface:del() + local fd = self:getfd(); + if fd < 0 then + return nil, "invalid fd"; + end + if fds[fd] ~= self then + return nil, "unregistered fd"; + end + local ok, err, errno = poll:del(fd); + if not ok and errno ~= ENOENT then + log("error", "Could not unregister %s: %s(%d)", self, err, errno); + return ok, err; + end + self._wantread, self._wantwrite = nil, nil; + fds[fd] = nil; + log("debug", "Unwatched %s", self); + return true; +end + +function interface:setflags(r, w) + if not(self._wantread or self._wantwrite) then + if not(r or w) then + return true; -- no change + end + return self:add(r, w); + end + if not(r or w) then + return self:del(); + end + return self:set(r, w); +end + +-- Called when socket is readable +function interface:onreadable() + local data, err, partial = self.conn:receive(self.read_size or cfg.read_size); + if data then + self:onconnect(); + self:on("incoming", data); + else + if partial and partial ~= "" then + self:onconnect(); + self:on("incoming", partial, err); + end + if err == "wantread" then + self:set(true, nil); + elseif err == "wantwrite" then + self:set(nil, true); + elseif err ~= "timeout" then + self:on("disconnect", err); + self:destroy() + return; + end + end + if not self.conn then return; end + if self.conn:dirty() then + self:setreadtimeout(false); + self:pausefor(cfg.read_retry_delay); + else + self:setreadtimeout(); + end +end + +-- Called when socket is writable +function interface:onwritable() + self:onconnect(); + if not self.conn then return; end -- could have been closed in onconnect + local buffer = self.writebuffer; + local data = t_concat(buffer); + local ok, err, partial = self.conn:send(data); + if ok then + self:set(nil, false); + for i = #buffer, 1, -1 do + buffer[i] = nil; + end + self:setwritetimeout(false); + self:ondrain(); -- Be aware of writes in ondrain + return; + elseif partial then + buffer[1] = data:sub(partial+1); + for i = #buffer, 2, -1 do + buffer[i] = nil; + end + self:setwritetimeout(); + end + if err == "wantwrite" or err == "timeout" then + self:set(nil, true); + elseif err == "wantread" then + self:set(true, nil); + elseif err ~= "timeout" then + self:on("disconnect", err); + self:destroy(); + end +end + +-- The write buffer has been successfully emptied +function interface:ondrain() + return self:on("drain"); +end + +-- Add data to write buffer and set flag for wanting to write +function interface:write(data) + local buffer = self.writebuffer; + if buffer then + t_insert(buffer, data); + else + self.writebuffer = { data }; + end + self:setwritetimeout(); + self:set(nil, true); + return #data; +end +interface.send = interface.write; + +-- Close, possibly after writing is done +function interface:close() + if self.writebuffer and self.writebuffer[1] then + self:set(false, true); -- Flush final buffer contents + self.write, self.send = noop, noop; -- No more writing + log("debug", "Close %s after writing", self); + self.ondrain = interface.close; + else + log("debug", "Close %s now", self); + self.write, self.send = noop, noop; + self.close = noop; + self:on("disconnect"); + self:destroy(); + end +end + +function interface:destroy() + self:del(); + self:setwritetimeout(false); + self:setreadtimeout(false); + self.onreadable = noop; + self.onwritable = noop; + self.destroy = noop; + self.close = noop; + self.on = noop; + self.conn:close(); + self.conn = nil; +end + +function interface:ssl() + return self._tls; +end + +function interface:starttls(tls_ctx) + if tls_ctx then self.tls_ctx = tls_ctx; end + self.starttls = false; + if self.writebuffer and self.writebuffer[1] then + log("debug", "Start TLS on %s after write", self); + self.ondrain = interface.starttls; + self:set(nil, true); -- make sure wantwrite is set + else + if self.ondrain == interface.starttls then + self.ondrain = nil; + end + self.onwritable = interface.tlshandskake; + self.onreadable = interface.tlshandskake; + self:set(true, true); + log("debug", "Prepare to start TLS on %s", self); + end +end + +function interface:tlshandskake() + self:setwritetimeout(false); + self:setreadtimeout(false); + if not self._tls then + self._tls = true; + log("debug", "Start TLS on %s now", self); + self:del(); + local ok, conn, err = pcall(luasec.wrap, self.conn, self.tls_ctx); + if not ok then + conn, err = ok, conn; + log("error", "Failed to initialize TLS: %s", err); + end + if not conn then + self:on("disconnect", err); + self:destroy(); + return conn, err; + end + conn:settimeout(0); + self.conn = conn; + self:on("starttls"); + self.ondrain = nil; + self.onwritable = interface.tlshandskake; + self.onreadable = interface.tlshandskake; + return self:init(); + end + local ok, err = self.conn:dohandshake(); + if ok then + log("debug", "TLS handshake on %s complete", self); + self.onwritable = nil; + self.onreadable = nil; + self:on("status", "ssl-handshake-complete"); + self:setwritetimeout(); + self:set(true, true); + elseif err == "wantread" then + log("debug", "TLS handshake on %s to wait until readable", self); + self:set(true, false); + self:setreadtimeout(cfg.handshake_timeout); + elseif err == "wantwrite" then + log("debug", "TLS handshake on %s to wait until writable", self); + self:set(false, true); + self:setwritetimeout(cfg.handshake_timeout); + else + log("debug", "TLS handshake error on %s: %s", self, err); + self:on("disconnect", err); + self:destroy(); + end +end + +local function wrapsocket(client, server, read_size, listeners, tls_ctx) -- luasocket object -> interface object + client:settimeout(0); + local conn = setmetatable({ + conn = client; + _server = server; + created = gettime(); + listeners = listeners; + read_size = read_size or (server and server.read_size); + writebuffer = {}; + tls_ctx = tls_ctx or (server and server.tls_ctx); + tls_direct = server and server.tls_direct; + }, interface_mt); + + conn:updatenames(); + return conn; +end + +function interface:updatenames() + local conn = self.conn; + local ok, peername, peerport = pcall(conn.getpeername, conn); + if ok then + self.peername, self.peerport = peername, peerport; + end + local ok, sockname, sockport = pcall(conn.getsockname, conn); + if ok then + self.sockname, self.sockport = sockname, sockport; + end +end + +-- A server interface has new incoming connections waiting +-- This replaces the onreadable callback +function interface:onacceptable() + local conn, err = self.conn:accept(); + if not conn then + log("debug", "Error accepting new client: %s, server will be paused for %ds", err, cfg.accept_retry_interval); + self:pausefor(cfg.accept_retry_interval); + return; + end + local client = wrapsocket(conn, self, nil, self.listeners); + log("debug", "New connection %s", tostring(client)); + client:init(); + if self.tls_direct then + client:starttls(self.tls_ctx); + end +end + +-- Initialization +function interface:init() + self:setwritetimeout(); + return self:add(true, true); +end + +function interface:pause() + return self:set(false); +end + +function interface:resume() + return self:set(true); +end + +-- Pause connection for some time +function interface:pausefor(t) + if self._pausefor then + self._pausefor:close(); + end + if t == false then return; end + self:set(false); + self._pausefor = addtimer(t, function () + self._pausefor = nil; + if self.conn and self.conn:dirty() then + self:onreadable(); + end + self:set(true); + end); +end + +-- Connected! +function interface:onconnect() + if self.conn and not self.peername and self.conn.getpeername then + self.peername, self.peerport = self.conn:getpeername(); + end + self.onconnect = noop; + self:on("connect"); +end + +local function addserver(addr, port, listeners, read_size, tls_ctx) + local conn, err = socket.bind(addr, port, cfg.tcp_backlog); + if not conn then return conn, err; end + conn:settimeout(0); + local server = setmetatable({ + conn = conn; + created = gettime(); + listeners = listeners; + read_size = read_size; + onreadable = interface.onacceptable; + tls_ctx = tls_ctx; + tls_direct = tls_ctx and true or false; + sockname = addr; + sockport = port; + }, interface_mt); + server:add(true, false); + return server; +end + +-- COMPAT +local function wrapclient(conn, addr, port, listeners, read_size, tls_ctx) + local client = wrapsocket(conn, nil, read_size, listeners, tls_ctx); + if not client.peername then + client.peername, client.peerport = addr, port; + end + local ok, err = client:init(); + if not ok then return ok, err; end + if tls_ctx then + client:starttls(tls_ctx); + end + return client; +end + +-- New outgoing TCP connection +local function addclient(addr, port, listeners, read_size, tls_ctx, typ) + local create; + if not typ then + local n = inet_pton(addr); + if not n then return nil, "invalid-ip"; end + if #n == 16 then + typ = "tcp6"; + else + typ = "tcp4"; + end + end + if typ then + create = socket[typ]; + end + if type(create) ~= "function" then + return nil, "invalid socket type"; + end + local conn, err = create(); + local ok, err = conn:settimeout(0); + if not ok then return ok, err; end + local ok, err = conn:setpeername(addr, port); + if not ok and err ~= "timeout" then return ok, err; end + local client = wrapsocket(conn, nil, read_size, listeners, tls_ctx) + local ok, err = client:init(); + if not ok then return ok, err; end + if tls_ctx then + client:starttls(tls_ctx); + end + return client, conn; +end + +local function watchfd(fd, onreadable, onwritable) + local conn = setmetatable({ + conn = fd; + onreadable = onreadable; + onwritable = onwritable; + close = function (self) + self:del(); + end + }, interface_mt); + if type(fd) == "number" then + conn.getfd = function () + return fd; + end; + -- Otherwise it'll need to be something LuaSocket-compatible + end + conn:add(onreadable, onwritable); + return conn; +end; + +-- Dump all data from one connection into another +local function link(from, to) + from.listeners = setmetatable({ + onincoming = function (_, data) + from:pause(); + to:write(data); + end, + }, {__index=from.listeners}); + to.listeners = setmetatable({ + ondrain = function () + from:resume(); + end, + }, {__index=to.listeners}); + from:set(true, nil); + to:set(nil, true); +end + +-- COMPAT +-- net.adns calls this but then replaces :send so this can be a noop +function interface:set_send(new_send) -- luacheck: ignore 212 +end + +-- Close all connections and servers +local function closeall() + for fd, conn in pairs(fds) do -- luacheck: ignore 213/fd + conn:close(); + end +end + +local quitting = nil; + +-- Signal main loop about shutdown via above upvalue +local function setquitting(quit) + if quit then + quitting = "quitting"; + closeall(); + else + quitting = nil; + end +end + +-- Main loop +local function loop(once) + repeat + local t = runtimers(cfg.max_wait, cfg.min_wait); + local fd, r, w = poll:wait(t); + if fd then + local conn = fds[fd]; + if conn then + if r then + conn:onreadable(); + end + if w then + conn:onwritable(); + end + else + log("debug", "Removing unknown fd %d", fd); + poll:del(fd); + end + elseif r ~= "timeout" and r ~= "signal" then + log("debug", "epoll_wait error: %s[%d]", r, w); + end + until once or (quitting and next(fds) == nil); + return quitting; +end + +return { + get_backend = function () return "epoll"; end; + addserver = addserver; + addclient = addclient; + add_task = addtimer; + at = at; + loop = loop; + closeall = closeall; + setquitting = setquitting; + wrapclient = wrapclient; + watchfd = watchfd; + link = link; + set_config = function (newconfig) + cfg = setmetatable(newconfig, default_config); + end; + + -- libevent emulation + event = { EV_READ = "r", EV_WRITE = "w", EV_READWRITE = "rw", EV_LEAVE = -1 }; + addevent = function (fd, mode, callback) + local function onevent(self) + local ret = self:callback(); + if ret == -1 then + self:set(false, false); + elseif ret then + self:set(mode == "r" or mode == "rw", mode == "w" or mode == "rw"); + end + end + + local conn = setmetatable({ + getfd = function () return fd; end; + callback = callback; + onreadable = onevent; + onwritable = onevent; + close = function (self) + self:del(); + fds[fd] = nil; + end; + }, interface_mt); + local ok, err = conn:add(mode == "r" or mode == "rw", mode == "w" or mode == "rw"); + if not ok then return ok, err; end + return conn; + end; +}; |