net/server_event.lua

   1 --[[
   2
   3
   4                         server.lua based on lua/libevent by blastbeat
   5
   6                         notes:
   7                         -- when using luaevent, never register 2 or more EV_READ at one socket, same for EV_WRITE
   8                         -- you cant even register a new EV_READ/EV_WRITE callback inside another one
   9                         -- to do some of the above, use timeout events or something what will called from outside
  10                         -- dont let garbagecollect eventcallbacks, as long they are running
  11                         -- when using luasec, there are 4 cases of timeout errors: wantread or wantwrite during reading or writing
  12
  13 --]]
  14
  15 local SCRIPT_NAME           = "server_event.lua"
  16 local SCRIPT_VERSION        = "0.05"
  17 local SCRIPT_AUTHOR         = "blastbeat"
  18 local LAST_MODIFIED         = "2009/11/20"
  19
  20 local cfg = {
  21         MAX_CONNECTIONS       = 100000,  -- max per server connections (use "ulimit -n" on *nix)
  22         MAX_HANDSHAKE_ATTEMPTS= 1000,  -- attempts to finish ssl handshake
  23         HANDSHAKE_TIMEOUT     = 60,  -- timeout in seconds per handshake attempt
  24         MAX_READ_LENGTH       = 1024 * 1024 * 1024 * 1024,  -- max bytes allowed to read from sockets
  25         MAX_SEND_LENGTH       = 1024 * 1024 * 1024 * 1024,  -- max bytes size of write buffer (for writing on sockets)
  26         ACCEPT_DELAY          = 10,  -- seconds to wait until the next attempt of a full server to accept
  27         READ_TIMEOUT          = 60 * 60 * 6,  -- timeout in seconds for read data from socket
  28         WRITE_TIMEOUT         = 180,  -- timeout in seconds for write data on socket
  29         CONNECT_TIMEOUT       = 20,  -- timeout in seconds for connection attempts
  30         CLEAR_DELAY           = 5,  -- seconds to wait for clearing interface list (and calling ondisconnect listeners)
  31         DEBUG                 = true,  -- show debug messages
  32 }
  33
  34 local function use(x) return rawget(_G, x); end
  35 local ipairs = use "ipairs"
  36 local string = use "string"
  37 local select = use "select"
  38 local require = use "require"
  39 local tostring = use "tostring"
  40 local coroutine = use "coroutine"
  41 local setmetatable = use "setmetatable"
  42
  43 local ssl = use "ssl"
  44 local socket = use "socket" or require "socket"
  45
  46 local log = require ("util.logger").init("socket")
  47
  48 local function debug(...)
  49         return log("debug", ("%s "):rep(select('#', ...)), ...)
  50 end
  51 local vdebug = debug;
  52
  53 local bitor = ( function( ) -- thx Rici Lake
  54         local hasbit = function( x, p )
  55                 return x % ( p + p ) >= p
  56         end
  57         return function( x, y )
  58                 local p = 1
  59                 local z = 0
  60                 local limit = x > y and x or y
  61                 while p <= limit do
  62                         if hasbit( x, p ) or hasbit( y, p ) then
  63                                 z = z + p
  64                         end
  65                         p = p + p
  66                 end
  67                 return z
  68         end
  69 end )( )
  70
  71 local event = require "luaevent.core"
  72 local base = event.new( )
  73 local EV_READ = event.EV_READ
  74 local EV_WRITE = event.EV_WRITE
  75 local EV_TIMEOUT = event.EV_TIMEOUT
  76 local EV_SIGNAL = event.EV_SIGNAL
  77
  78 local EV_READWRITE = bitor( EV_READ, EV_WRITE )
  79
  80 local interfacelist = ( function( )  -- holds the interfaces for sockets
  81         local array = { }
  82         local len = 0
  83         return function( method, arg )
  84                 if "add" == method then
  85                         len = len + 1
  86                         array[ len ] = arg
  87                         arg:_position( len )
  88                         return len
  89                 elseif "delete" == method then
  90                         if len <= 0 then
  91                                 return nil, "array is already empty"
  92                         end
  93                         local position = arg:_position()  -- get position in array
  94                         if position ~= len then
  95                                 local interface = array[ len ]  -- get last interface
  96                                 array[ position ] = interface  -- copy it into free position
  97                                 array[ len ] = nil  -- free last position
  98                                 interface:_position( position )  -- set new position in array
  99                         else  -- free last position
 100                                 array[ len ] = nil
 101                         end
 102                         len = len - 1
 103                         return len
 104                 else
 105                         return array
 106                 end
 107         end
 108 end )( )
 109
 110 -- Client interface methods
 111 local interface_mt
 112 do
 113         interface_mt = {}; interface_mt.__index = interface_mt;
 114
 115         local addevent = base.addevent
 116         local coroutine_wrap, coroutine_yield = coroutine.wrap,coroutine.yield
 117
 118         -- Private methods
 119         function interface_mt:_position(new_position)
 120                         self.position = new_position or self.position
 121                         return self.position;
 122         end
 123         function interface_mt:_close() -- regs event to start self:_destroy()
 124                         local callback = function( )
 125                                 self:_destroy();
 126                                 self.eventclose = nil
 127                                 return -1
 128                         end
 129                         self.eventclose = addevent( base, nil, EV_TIMEOUT, callback, 0 )
 130                         return true
 131         end
 132
 133         function interface_mt:_start_connection(plainssl) -- should be called from addclient
 134                         local callback = function( event )
 135                                 if EV_TIMEOUT == event then  -- timeout during connection
 136                                         self.fatalerror = "connection timeout"
 137                                         self:ontimeout()  -- call timeout listener
 138                                         self:_close()
 139                                         debug( "new connection failed. id:", self.id, "error:", self.fatalerror )
 140                                 else
 141                                         if plainssl and ssl then  -- start ssl session
 142                                                 self:starttls(self._sslctx, true)
 143                                         else  -- normal connection
 144                                                 self:_start_session(true)
 145                                         end
 146                                         debug( "new connection established. id:", self.id )
 147                                 end
 148                                 self.eventconnect = nil
 149                                 return -1
 150                         end
 151                         self.eventconnect = addevent( base, self.conn, EV_WRITE, callback, cfg.CONNECT_TIMEOUT )
 152                         return true
 153         end
 154         function interface_mt:_start_session(call_onconnect) -- new session, for example after startssl
 155                 if self.type == "client" then
 156                         local callback = function( )
 157                                 self:_lock( false,  false, false )
 158                                 --vdebug( "start listening on client socket with id:", self.id )
 159                                 self.eventread = addevent( base, self.conn, EV_READ, self.readcallback, cfg.READ_TIMEOUT );  -- register callback
 160                                 if call_onconnect then
 161                                         self:onconnect()
 162                                 end
 163                                 self.eventsession = nil
 164                                 return -1
 165                         end
 166                         self.eventsession = addevent( base, nil, EV_TIMEOUT, callback, 0 )
 167                 else
 168                         self:_lock( false )
 169                         --vdebug( "start listening on server socket with id:", self.id )
 170                         self.eventread = addevent( base, self.conn, EV_READ, self.readcallback )  -- register callback
 171                 end
 172                 return true
 173         end
 174         function interface_mt:_start_ssl(call_onconnect) -- old socket will be destroyed, therefore we have to close read/write events first
 175                         --vdebug( "starting ssl session with client id:", self.id )
 176                         local _
 177                         _ = self.eventread and self.eventread:close( )  -- close events; this must be called outside of the event callbacks!
 178                         _ = self.eventwrite and self.eventwrite:close( )
 179                         self.eventread, self.eventwrite = nil, nil
 180                         local err
 181                         self.conn, err = ssl.wrap( self.conn, self._sslctx )
 182                         if err then
 183                                 self.fatalerror = err
 184                                 self.conn = nil  -- cannot be used anymore
 185                                 if call_onconnect then
 186                                         self.ondisconnect = nil  -- dont call this when client isnt really connected
 187                                 end
 188                                 self:_close()
 189                                 debug( "fatal error while ssl wrapping:", err )
 190                                 return false
 191                         end
 192                         self.conn:settimeout( 0 )  -- set non blocking
 193                         local handshakecallback = coroutine_wrap(
 194                                 function( event )
 195                                         local _, err
 196                                         local attempt = 0
 197                                         local maxattempt = cfg.MAX_HANDSHAKE_ATTEMPTS
 198                                         while attempt < maxattempt do  -- no endless loop
 199                                                 attempt = attempt + 1
 200                                                 debug( "ssl handshake of client with id:"..tostring(self)..", attempt:"..attempt )
 201                                                 if attempt > maxattempt then
 202                                                         self.fatalerror = "max handshake attempts exceeded"
 203                                                 elseif EV_TIMEOUT == event then
 204                                                         self.fatalerror = "timeout during handshake"
 205                                                 else
 206                                                         _, err = self.conn:dohandshake( )
 207                                                         if not err then
 208                                                                 self:_lock( false, false, false )  -- unlock the interface; sending, closing etc allowed
 209                                                                 self.send = self.conn.send  -- caching table lookups with new client object
 210                                                                 self.receive = self.conn.receive
 211                                                                 if not call_onconnect then  -- trigger listener
 212                                                                         self:onstatus("ssl-handshake-complete");
 213                                                                 end
 214                                                                 self:_start_session( call_onconnect )
 215                                                                 debug( "ssl handshake done" )
 216                                                                 self.eventhandshake = nil
 217                                                                 return -1
 218                                                         end
 219                                                         if err == "wantwrite" then
 220                                                                 event = EV_WRITE
 221                                                         elseif err == "wantread" then
 222                                                                 event = EV_READ
 223                                                         else
 224                                                                 debug( "ssl handshake error:", err )
 225                                                                 self.fatalerror = err
 226                                                         end
 227                                                 end
 228                                                 if self.fatalerror then
 229                                                         if call_onconnect then
 230                                                                 self.ondisconnect = nil  -- dont call this when client isnt really connected
 231                                                         end
 232                                                         self:_close()
 233                                                         debug( "handshake failed because:", self.fatalerror )
 234                                                         self.eventhandshake = nil
 235                                                         return -1
 236                                                 end
 237                                                 event = coroutine_yield( event, cfg.HANDSHAKE_TIMEOUT )  -- yield this monster...
 238                                         end
 239                                 end
 240                         )
 241                         debug "starting handshake..."
 242                         self:_lock( false, true, true )  -- unlock read/write events, but keep interface locked
 243                         self.eventhandshake = addevent( base, self.conn, EV_READWRITE, handshakecallback, cfg.HANDSHAKE_TIMEOUT )
 244                         return true
 245         end
 246         function interface_mt:_destroy()  -- close this interface + events and call last listener
 247                         debug( "closing client with id:", self.id, self.fatalerror )
 248                         self:_lock( true, true, true )  -- first of all, lock the interface to avoid further actions
 249                         local _
 250                         _ = self.eventread and self.eventread:close( )
 251                         if self.type == "client" then
 252                                 _ = self.eventwrite and self.eventwrite:close( )
 253                                 _ = self.eventhandshake and self.eventhandshake:close( )
 254                                 _ = self.eventstarthandshake and self.eventstarthandshake:close( )
 255                                 _ = self.eventconnect and self.eventconnect:close( )
 256                                 _ = self.eventsession and self.eventsession:close( )
 257                                 _ = self.eventwritetimeout and self.eventwritetimeout:close( )
 258                                 _ = self.eventreadtimeout and self.eventreadtimeout:close( )
 259                                 _ = self.ondisconnect and self:ondisconnect( self.fatalerror ~= "client to close" and self.fatalerror)  -- call ondisconnect listener (wont be the case if handshake failed on connect)
 260                                 _ = self.conn and self.conn:close( ) -- close connection
 261                                 _ = self._server and self._server:counter(-1);
 262                                 self.eventread, self.eventwrite = nil, nil
 263                                 self.eventstarthandshake, self.eventhandshake, self.eventclose = nil, nil, nil
 264                                 self.readcallback, self.writecallback = nil, nil
 265                         else
 266                                 self.conn:close( )
 267                                 self.eventread, self.eventclose = nil, nil
 268                                 self.interface, self.readcallback = nil, nil
 269                         end
 270                         interfacelist( "delete", self )
 271                         return true
 272         end
 273
 274         function interface_mt:_lock(nointerface, noreading, nowriting)  -- lock or unlock this interface or events
 275                         self.nointerface, self.noreading, self.nowriting = nointerface, noreading, nowriting
 276                         return nointerface, noreading, nowriting
 277         end
 278
 279         --TODO: Deprecate
 280         function interface_mt:lock_read(switch)
 281                 if switch then
 282                         return self:pause();
 283                 else
 284                         return self:resume();
 285                 end
 286         end
 287
 288         function interface_mt:pause()
 289                 return self:_lock(self.nointerface, true, self.nowriting);
 290         end
 291
 292         function interface_mt:resume()
 293                 self:_lock(self.nointerface, false, self.nowriting);
 294                 if not self.eventread then
 295                         self.eventread = addevent( base, self.conn, EV_READ, self.readcallback, cfg.READ_TIMEOUT );  -- register callback
 296                 end
 297         end
 298
 299         function interface_mt:counter(c)
 300                 if c then
 301                         self._connections = self._connections + c
 302                 end
 303                 return self._connections
 304         end
 305
 306         -- Public methods
 307         function interface_mt:write(data)
 308                 if self.nowriting then return nil, "locked" end
 309                 --vdebug( "try to send data to client, id/data:", self.id, data )
 310                 data = tostring( data )
 311                 local len = #data
 312                 local total = len + self.writebufferlen
 313                 if total > cfg.MAX_SEND_LENGTH then  -- check buffer length
 314                         local err = "send buffer exceeded"
 315                         debug( "error:", err )  -- to much, check your app
 316                         return nil, err
 317                 end
 318                 self.writebuffer = self.writebuffer .. data -- new buffer
 319                 self.writebufferlen = total
 320                 if not self.eventwrite then  -- register new write event
 321                         --vdebug( "register new write event" )
 322                         self.eventwrite = addevent( base, self.conn, EV_WRITE, self.writecallback, cfg.WRITE_TIMEOUT )
 323                 end
 324                 return true
 325         end
 326         function interface_mt:close()
 327                 if self.nointerface then return nil, "locked"; end
 328                 debug( "try to close client connection with id:", self.id )
 329                 if self.type == "client" then
 330                         self.fatalerror = "client to close"
 331                         if self.eventwrite then -- wait for incomplete write request
 332                                 self:_lock( true, true, false )
 333                                 debug "closing delayed until writebuffer is empty"
 334                                 return nil, "writebuffer not empty, waiting"
 335                         else -- close now
 336                                 self:_lock( true, true, true )
 337                                 self:_close()
 338                                 return true
 339                         end
 340                 else
 341                         debug( "try to close server with id:", tostring(self.id))
 342                         self.fatalerror = "server to close"
 343                         self:_lock( true )
 344                         self:_close( 0 )
 345                         return true
 346                 end
 347         end
 348
 349         function interface_mt:socket()
 350                 return self.conn
 351         end
 352
 353         function interface_mt:server()
 354                 return self._server or self;
 355         end
 356
 357         function interface_mt:port()
 358                 return self._port
 359         end
 360
 361         function interface_mt:serverport()
 362                 return self._serverport
 363         end
 364
 365         function interface_mt:ip()
 366                 return self._ip
 367         end
 368
 369         function interface_mt:ssl()
 370                 return self._usingssl
 371         end
 372
 373         function interface_mt:type()
 374                 return self._type or "client"
 375         end
 376
 377         function interface_mt:connections()
 378                 return self._connections
 379         end
 380
 381         function interface_mt:address()
 382                 return self.addr
 383         end
 384
 385         function interface_mt:set_sslctx(sslctx)
 386                 self._sslctx = sslctx;
 387                 if sslctx then
 388                         self.starttls = nil; -- use starttls() of interface_mt
 389                 else
 390                         self.starttls = false; -- prevent starttls()
 391                 end
 392         end
 393
 394         function interface_mt:set_mode(pattern)
 395                 if pattern then
 396                         self._pattern = pattern;
 397                 end
 398                 return self._pattern;
 399         end
 400
 401         function interface_mt:set_send(new_send)
 402                 -- No-op, we always use the underlying connection's send
 403         end
 404
 405         function interface_mt:starttls(sslctx, call_onconnect)
 406                 debug( "try to start ssl at client id:", self.id )
 407                 local err
 408                 self._sslctx = sslctx;
 409                 if self._usingssl then  -- startssl was already called
 410                         err = "ssl already active"
 411                 end
 412                 if err then
 413                         debug( "error:", err )
 414                         return nil, err
 415                 end
 416                 self._usingssl = true
 417                 self.startsslcallback = function( )  -- we have to start the handshake outside of a read/write event
 418                         self.startsslcallback = nil
 419                         self:_start_ssl(call_onconnect);
 420                         self.eventstarthandshake = nil
 421                         return -1
 422                 end
 423                 if not self.eventwrite then
 424                         self:_lock( true, true, true )  -- lock the interface, to not disturb the handshake
 425                         self.eventstarthandshake = addevent( base, nil, EV_TIMEOUT, self.startsslcallback, 0 )  -- add event to start handshake
 426                 else  -- wait until writebuffer is empty
 427                         self:_lock( true, true, false )
 428                         debug "ssl session delayed until writebuffer is empty..."
 429                 end
 430                 self.starttls = false;
 431                 return true
 432         end
 433
 434         function interface_mt:setoption(option, value)
 435                 if self.conn.setoption then
 436                         return self.conn:setoption(option, value);
 437                 end
 438                 return false, "setoption not implemented";
 439         end
 440
 441         function interface_mt:setlistener(listener)
 442                 self.onconnect, self.ondisconnect, self.onincoming, self.ontimeout, self.onstatus
 443                         = listener.onconnect, listener.ondisconnect, listener.onincoming, listener.ontimeout, listener.onstatus;
 444         end
 445
 446         -- Stub handlers
 447         function interface_mt:onconnect()
 448         end
 449         function interface_mt:onincoming()
 450         end
 451         function interface_mt:ondisconnect()
 452         end
 453         function interface_mt:ontimeout()
 454         end
 455         function interface_mt:ondrain()
 456         end
 457         function interface_mt:onstatus()
 458         end
 459 end
 460
 461 -- End of client interface methods
 462
 463 local handleclient;
 464 do
 465         local string_sub = string.sub  -- caching table lookups
 466         local string_len = string.len
 467         local addevent = base.addevent
 468         local socket_gettime = socket.gettime
 469         function handleclient( client, ip, port, server, pattern, listener, sslctx )  -- creates an client interface
 470                 --vdebug("creating client interfacce...")
 471                 local interface = {
 472                         type = "client";
 473                         conn = client;
 474                         currenttime = socket_gettime( );  -- safe the origin
 475                         writebuffer = "";  -- writebuffer
 476                         writebufferlen = 0;  -- length of writebuffer
 477                         send = client.send;  -- caching table lookups
 478                         receive = client.receive;
 479                         onconnect = listener.onconnect;  -- will be called when client disconnects
 480                         ondisconnect = listener.ondisconnect;  -- will be called when client disconnects
 481                         onincoming = listener.onincoming;  -- will be called when client sends data
 482                         ontimeout = listener.ontimeout; -- called when fatal socket timeout occurs
 483                         onstatus = listener.onstatus; -- called for status changes (e.g. of SSL/TLS)
 484                         eventread = false, eventwrite = false, eventclose = false,
 485                         eventhandshake = false, eventstarthandshake = false;  -- event handler
 486                         eventconnect = false, eventsession = false;  -- more event handler...
 487                         eventwritetimeout = false;  -- even more event handler...
 488                         eventreadtimeout = false;
 489                         fatalerror = false;  -- error message
 490                         writecallback = false;  -- will be called on write events
 491                         readcallback = false;  -- will be called on read events
 492                         nointerface = true;  -- lock/unlock parameter of this interface
 493                         noreading = false, nowriting = false;  -- locks of the read/writecallback
 494                         startsslcallback = false;  -- starting handshake callback
 495                         position = false;  -- position of client in interfacelist
 496
 497                         -- Properties
 498                         _ip = ip, _port = port, _server = server, _pattern = pattern,
 499                         _serverport = (server and server:port() or nil),
 500                         _sslctx = sslctx; -- parameters
 501                         _usingssl = false;  -- client is using ssl;
 502                 }
 503                 if not ssl then interface.starttls = false; end
 504                 interface.id = tostring(interface):match("%x+$");
 505                 interface.writecallback = function( event )  -- called on write events
 506                         --vdebug( "new client write event, id/ip/port:", interface, ip, port )
 507                         if interface.nowriting or ( interface.fatalerror and ( "client to close" ~= interface.fatalerror ) ) then  -- leave this event
 508                                 --vdebug( "leaving this event because:", interface.nowriting or interface.fatalerror )
 509                                 interface.eventwrite = false
 510                                 return -1
 511                         end
 512                         if EV_TIMEOUT == event then  -- took too long to write some data to socket -> disconnect
 513                                 interface.fatalerror = "timeout during writing"
 514                                 debug( "writing failed:", interface.fatalerror )
 515                                 interface:_close()
 516                                 interface.eventwrite = false
 517                                 return -1
 518                         else  -- can write :)
 519                                 if interface._usingssl then  -- handle luasec
 520                                         if interface.eventreadtimeout then  -- we have to read first
 521                                                 local ret = interface.readcallback( )  -- call readcallback
 522                                                 --vdebug( "tried to read in writecallback, result:", ret )
 523                                         end
 524                                         if interface.eventwritetimeout then  -- luasec only
 525                                                 interface.eventwritetimeout:close( )  -- first we have to close timeout event which where regged after a wantread error
 526                                                 interface.eventwritetimeout = false
 527                                         end
 528                                 end
 529                                 local succ, err, byte = interface.conn:send( interface.writebuffer, 1, interface.writebufferlen )
 530                                 --vdebug( "write data:", interface.writebuffer, "error:", err, "part:", byte )
 531                                 if succ then  -- writing succesful
 532                                         interface.writebuffer = ""
 533                                         interface.writebufferlen = 0
 534                                         interface:ondrain();
 535                                         if interface.fatalerror then
 536                                                 debug "closing client after writing"
 537                                                 interface:_close()  -- close interface if needed
 538                                         elseif interface.startsslcallback then  -- start ssl connection if needed
 539                                                 debug "starting ssl handshake after writing"
 540                                                 interface.eventstarthandshake = addevent( base, nil, EV_TIMEOUT, interface.startsslcallback, 0 )
 541                                         elseif interface.eventreadtimeout then
 542                                                 return EV_WRITE, EV_TIMEOUT
 543                                         end
 544                                         interface.eventwrite = nil
 545                                         return -1
 546                                 elseif byte and (err == "timeout" or err == "wantwrite") then  -- want write again
 547                                         --vdebug( "writebuffer is not empty:", err )
 548                                         interface.writebuffer = string_sub( interface.writebuffer, byte + 1, interface.writebufferlen )  -- new buffer
 549                                         interface.writebufferlen = interface.writebufferlen - byte
 550                                         if "wantread" == err then  -- happens only with luasec
 551                                                 local callback = function( )
 552                                                         interface:_close()
 553                                                         interface.eventwritetimeout = nil
 554                                                         return -1;
 555                                                 end
 556                                                 interface.eventwritetimeout = addevent( base, nil, EV_TIMEOUT, callback, cfg.WRITE_TIMEOUT )  -- reg a new timeout event
 557                                                 debug( "wantread during write attempt, reg it in readcallback but dont know what really happens next..." )
 558                                                 -- hopefully this works with luasec; its simply not possible to use 2 different write events on a socket in luaevent
 559                                                 return -1
 560                                         end
 561                                         return EV_WRITE, cfg.WRITE_TIMEOUT
 562                                 else  -- connection was closed during writing or fatal error
 563                                         interface.fatalerror = err or "fatal error"
 564                                         debug( "connection failed in write event:", interface.fatalerror )
 565                                         interface:_close()
 566                                         interface.eventwrite = nil
 567                                         return -1
 568                                 end
 569                         end
 570                 end
 571
 572                 interface.readcallback = function( event )  -- called on read events
 573                         --vdebug( "new client read event, id/ip/port:", tostring(interface.id), tostring(ip), tostring(port) )
 574                         if interface.noreading or interface.fatalerror then  -- leave this event
 575                                 --vdebug( "leaving this event because:", tostring(interface.noreading or interface.fatalerror) )
 576                                 interface.eventread = nil
 577                                 return -1
 578                         end
 579                         if EV_TIMEOUT == event then  -- took too long to get some data from client -> disconnect
 580                                 interface.fatalerror = "timeout during receiving"
 581                                 debug( "connection failed:", interface.fatalerror )
 582                                 interface:_close()
 583                                 interface.eventread = nil
 584                                 return -1
 585                         else -- can read
 586                                 if interface._usingssl then  -- handle luasec
 587                                         if interface.eventwritetimeout then  -- ok, in the past writecallback was regged
 588                                                 local ret = interface.writecallback( )  -- call it
 589                                                 --vdebug( "tried to write in readcallback, result:", tostring(ret) )
 590                                         end
 591                                         if interface.eventreadtimeout then
 592                                                 interface.eventreadtimeout:close( )
 593                                                 interface.eventreadtimeout = nil
 594                                         end
 595                                 end
 596                                 local buffer, err, part = interface.conn:receive( interface._pattern )  -- receive buffer with "pattern"
 597                                 --vdebug( "read data:", tostring(buffer), "error:", tostring(err), "part:", tostring(part) )
 598                                 buffer = buffer or part
 599                                 if buffer and #buffer > cfg.MAX_READ_LENGTH then  -- check buffer length
 600                                         interface.fatalerror = "receive buffer exceeded"
 601                                         debug( "fatal error:", interface.fatalerror )
 602                                         interface:_close()
 603                                         interface.eventread = nil
 604                                         return -1
 605                                 end
 606                                 if err and ( err ~= "timeout" and err ~= "wantread" ) then
 607                                         if "wantwrite" == err then -- need to read on write event
 608                                                 if not interface.eventwrite then  -- register new write event if needed
 609                                                         interface.eventwrite = addevent( base, interface.conn, EV_WRITE, interface.writecallback, cfg.WRITE_TIMEOUT )
 610                                                 end
 611                                                 interface.eventreadtimeout = addevent( base, nil, EV_TIMEOUT,
 612                                                         function( )
 613                                                                 interface:_close()
 614                                                         end, cfg.READ_TIMEOUT
 615                                                 )
 616                                                 debug( "wantwrite during read attempt, reg it in writecallback but dont know what really happens next..." )
 617                                                 -- to be honest i dont know what happens next, if it is allowed to first read, the write etc...
 618                                         else  -- connection was closed or fatal error
 619                                                 interface.fatalerror = err
 620                                                 debug( "connection failed in read event:", interface.fatalerror )
 621                                                 interface:_close()
 622                                                 interface.eventread = nil
 623                                                 return -1
 624                                         end
 625                                 else
 626                                         interface.onincoming( interface, buffer, err )  -- send new data to listener
 627                                 end
 628                                 if interface.noreading then
 629                                         interface.eventread = nil;
 630                                         return -1;
 631                                 end
 632                                 return EV_READ, cfg.READ_TIMEOUT
 633                         end
 634                 end
 635
 636                 client:settimeout( 0 )  -- set non blocking
 637                 setmetatable(interface, interface_mt)
 638                 interfacelist( "add", interface )  -- add to interfacelist
 639                 return interface
 640         end
 641 end
 642
 643 local handleserver
 644 do
 645         function handleserver( server, addr, port, pattern, listener, sslctx )  -- creates an server interface
 646                 debug "creating server interface..."
 647                 local interface = {
 648                         _connections = 0;
 649
 650                         conn = server;
 651                         onconnect = listener.onconnect;  -- will be called when new client connected
 652                         eventread = false;  -- read event handler
 653                         eventclose = false; -- close event handler
 654                         readcallback = false; -- read event callback
 655                         fatalerror = false; -- error message
 656                         nointerface = true;  -- lock/unlock parameter
 657
 658                         _ip = addr, _port = port, _pattern = pattern,
 659                         _sslctx = sslctx;
 660                 }
 661                 interface.id = tostring(interface):match("%x+$");
 662                 interface.readcallback = function( event )  -- server handler, called on incoming connections
 663                         --vdebug( "server can accept, id/addr/port:", interface, addr, port )
 664                         if interface.fatalerror then
 665                                 --vdebug( "leaving this event because:", self.fatalerror )
 666                                 interface.eventread = nil
 667                                 return -1
 668                         end
 669                         local delay = cfg.ACCEPT_DELAY
 670                         if EV_TIMEOUT == event then
 671                                 if interface._connections >= cfg.MAX_CONNECTIONS then  -- check connection count
 672                                         debug( "to many connections, seconds to wait for next accept:", delay )
 673                                         return EV_TIMEOUT, delay  -- timeout...
 674                                 else
 675                                         return EV_READ  -- accept again
 676                                 end
 677                         end
 678                         --vdebug("max connection check ok, accepting...")
 679                         local client, err = server:accept()    -- try to accept; TODO: check err
 680                         while client do
 681                                 if interface._connections >= cfg.MAX_CONNECTIONS then
 682                                         client:close( )  -- refuse connection
 683                                         debug( "maximal connections reached, refuse client connection; accept delay:", delay )
 684                                         return EV_TIMEOUT, delay  -- delay for next accept attempt
 685                                 end
 686                                 local client_ip, client_port = client:getpeername( )
 687                                 interface._connections = interface._connections + 1  -- increase connection count
 688                                 local clientinterface = handleclient( client, client_ip, client_port, interface, pattern, listener, sslctx )
 689                                 --vdebug( "client id:", clientinterface, "startssl:", startssl )
 690                                 if ssl and sslctx then
 691                                         clientinterface:starttls(sslctx, true)
 692                                 else
 693                                         clientinterface:_start_session( true )
 694                                 end
 695                                 debug( "accepted incoming client connection from:", client_ip or "<unknown IP>", client_port or "<unknown port>", "to", port or "<unknown port>");
 696
 697                                 client, err = server:accept()    -- try to accept again
 698                         end
 699                         return EV_READ
 700                 end
 701
 702                 server:settimeout( 0 )
 703                 setmetatable(interface, interface_mt)
 704                 interfacelist( "add", interface )
 705                 interface:_start_session()
 706                 return interface
 707         end
 708 end
 709
 710 local addserver = ( function( )
 711         return function( addr, port, listener, pattern, sslcfg, startssl )  -- TODO: check arguments
 712                 --vdebug( "creating new tcp server with following parameters:", addr or "nil", port or "nil", sslcfg or "nil", startssl or "nil")
 713                 local server, err = socket.bind( addr, port, cfg.ACCEPT_QUEUE )  -- create server socket
 714                 if not server then
 715                         debug( "creating server socket on "..addr.." port "..port.." failed:", err )
 716                         return nil, err
 717                 end
 718                 local sslctx
 719                 if sslcfg then
 720                         if not ssl then
 721                                 debug "fatal error: luasec not found"
 722                                 return nil, "luasec not found"
 723                         end
 724                         sslctx, err = sslcfg
 725                         if err then
 726                                 debug( "error while creating new ssl context for server socket:", err )
 727                                 return nil, err
 728                         end
 729                 end
 730                 local interface = handleserver( server, addr, port, pattern, listener, sslctx, startssl )  -- new server handler
 731                 debug( "new server created with id:", tostring(interface))
 732                 return interface
 733         end
 734 end )( )
 735
 736 local addclient, wrapclient
 737 do
 738         function wrapclient( client, ip, port, listeners, pattern, sslctx )
 739                 local interface = handleclient( client, ip, port, nil, pattern, listeners, sslctx )
 740                 interface:_start_connection(sslctx)
 741                 return interface, client
 742                 --function handleclient( client, ip, port, server, pattern, listener, _, sslctx )  -- creates an client interface
 743         end
 744
 745         function addclient( addr, serverport, listener, pattern, localaddr, localport, sslcfg, startssl )
 746                 local client, err = socket.tcp()  -- creating new socket
 747                 if not client then
 748                         debug( "cannot create socket:", err )
 749                         return nil, err
 750                 end
 751                 client:settimeout( 0 )  -- set nonblocking
 752                 if localaddr then
 753                         local res, err = client:bind( localaddr, localport, -1 )
 754                         if not res then
 755                                 debug( "cannot bind client:", err )
 756                                 return nil, err
 757                         end
 758                 end
 759                 local sslctx
 760                 if sslcfg then  -- handle ssl/new context
 761                         if not ssl then
 762                                 debug "need luasec, but not available"
 763                                 return nil, "luasec not found"
 764                         end
 765                         sslctx, err = sslcfg
 766                         if err then
 767                                 debug( "cannot create new ssl context:", err )
 768                                 return nil, err
 769                         end
 770                 end
 771                 local res, err = client:connect( addr, serverport )  -- connect
 772                 if res or ( err == "timeout" ) then
 773                         local ip, port = client:getsockname( )
 774                         local interface = wrapclient( client, ip, serverport, listener, pattern, sslctx, startssl )
 775                         interface:_start_connection( startssl )
 776                         debug( "new connection id:", interface.id )
 777                         return interface, err
 778                 else
 779                         debug( "new connection failed:", err )
 780                         return nil, err
 781                 end
 782         end
 783 end
 784
 785
 786 local loop = function( )  -- starts the event loop
 787         base:loop( )
 788         return "quitting";
 789 end
 790
 791 local newevent = ( function( )
 792         local add = base.addevent
 793         return function( ... )
 794                 return add( base, ... )
 795         end
 796 end )( )
 797
 798 local closeallservers = function( arg )
 799         for _, item in ipairs( interfacelist( ) ) do
 800                 if item.type == "server" then
 801                         item:close( arg )
 802                 end
 803         end
 804 end
 805
 806 local function setquitting(yes)
 807         if yes then
 808                  -- Quit now
 809                  closeallservers();
 810                  base:loopexit();
 811         end
 812 end
 813
 814 local function get_backend()
 815         return base:method();
 816 end
 817
 818 -- We need to hold onto the events to stop them
 819 -- being garbage-collected
 820 local signal_events = {}; -- [signal_num] -> event object
 821 local function hook_signal(signal_num, handler)
 822         local function _handler(event)
 823                 local ret = handler();
 824                 if ret ~= false then -- Continue handling this signal?
 825                         return EV_SIGNAL; -- Yes
 826                 end
 827                 return -1; -- Close this event
 828         end
 829         signal_events[signal_num] = base:addevent(signal_num, EV_SIGNAL, _handler);
 830         return signal_events[signal_num];
 831 end
 832
 833 local function link(sender, receiver, buffersize)
 834         local sender_locked;
 835
 836         function receiver:ondrain()
 837                 if sender_locked then
 838                         sender:resume();
 839                         sender_locked = nil;
 840                 end
 841         end
 842
 843         function sender:onincoming(data)
 844                 receiver:write(data);
 845                 if receiver.writebufferlen >= buffersize then
 846                         sender_locked = true;
 847                         sender:pause();
 848                 end
 849         end
 850 end
 851
 852 return {
 853
 854         cfg = cfg,
 855         base = base,
 856         loop = loop,
 857         link = link,
 858         event = event,
 859         event_base = base,
 860         addevent = newevent,
 861         addserver = addserver,
 862         addclient = addclient,
 863         wrapclient = wrapclient,
 864         setquitting = setquitting,
 865         closeall = closeallservers,
 866         get_backend = get_backend,
 867         hook_signal = hook_signal,
 868
 869         __NAME = SCRIPT_NAME,
 870         __DATE = LAST_MODIFIED,
 871         __AUTHOR = SCRIPT_AUTHOR,
 872         __VERSION = SCRIPT_VERSION,
 873
 874 }