Accommodate IPv6 addresses at packet level. Avoid infinite loops in deserialisation. Test with timing loop removed.

src/client/assets/strings/english.lua

@@ -19,4 +19,5 @@ return setmetatable({
   ["svinfo_port"] = "Port",
   ["refresh_button"] = "Refresh",
   ["cancel_button"] = "Cancel",
+  game_intro = "A gaze blank and pitiless as the sun",
 }, {__index = function( t, k ) return k end } )

src/client/game.lua

@@ -6,22 +6,44 @@ local packet = shared.packet
 local crepuscular = assert( require 'crepuscular' )
 
 local game = {}
+local handlers = setmetatable( {}, {__index = function() return print end } )
 local t = 0
 local tick = 0
-local serverTick = "0"
+local serverTick = 0
 
+function handlers.connected( data )
+  serverTick = math.max( data.tick, serverTick )
+end
+
+function handlers.insect( data )
+  
+end
+
+function handlers.soleil( data )
+  
+end
+
+function handlers.playerChange( data )
+  
+end
+
+function handlers.chatMessage( msg )
+  print( msg.cmsg )
+end
 
 function game.draw()
+  lg.setColor( 1, 1, 1, 1 )
   lg.print( tick, 0, 0 )
   lg.print( serverTick, 0, 25 )
 end
 
 function game.onPacket( msg )
-  if not msg then return end
+  if not msg or (#msg < 1) then return end
   local msgs, types = packet.deserialise( msg )
   if not msgs then return game.onPacket( server.receive() ) end
   for i = 1, #msgs do
-    game[ types[i] ]( msgs[i], ip, port )
+    --Handler returns something if msg should be discarded.
+    if handlers[ types[i] ]( msgs[i] ) then break end
   end
   return game.onPacket( server.receive() )
 end
@@ -32,7 +54,8 @@ function game.update( dt )
   if t > 0.1 then
     t = 0
     tick = tick + 1
-    assert( server.send( packet.get( packet.heartbeat{ tick = tick, hash = 1234 } ) ) )
+    server.newPacket()
+    assert( server.send( packet.get() ) )
   end
 end
 

src/client/udp.lua

@@ -31,6 +31,11 @@ function udp.requestServerList()
   return mscxn:send( packet.get() )
 end
 
+function udp.newPacket( tick )
+  packet.get()
+  if token then packet.connected{ token = token, tick = tick or 0 } end
+end
+
 function udp.setToken( token )
   token = token
 end
@@ -51,6 +56,7 @@ end
 
 function udp.connect( ip, port )
   assert( cxn:setpeername( ip, port ) )
+  print( "Connection request to:", ip, port )
   return udp.send( packet.get( packet.clientInfo{ username = config.plName } ) )
 end
 
@@ -61,7 +67,6 @@ function udp.disconnect( )
 end
 
 function udp.send( s )
-  print( "udp out:", s )
   return cxn:send( s )
 end
 

src/client/ui/browser.lua

@@ -210,6 +210,8 @@ end
 
 function browser.joinIPString( s )
   --Parse IP address and port from string. If it's valid, join the server.
+  --TODO: there should be two fields, one for IP, one for port.
+  --Parsing the entered address for the port is possible but more error-prone.
   print( "browser: entered IP and port", s )
   if not s then return end
   ti:clear()

src/metaserver/conf.lua

@@ -34,18 +34,18 @@ function love.conf(t)
     t.modules.data = true               -- Enable the data module (boolean)
     t.modules.event = true              -- Enable the event module (boolean)
     t.modules.font = false              -- Enable the font module (boolean)
-    t.modules.graphics = true           -- Enable the graphics module (boolean)
+    t.modules.graphics = false          -- Enable the graphics module (boolean)
-    t.modules.image = true              -- Enable the image module (boolean)
+    t.modules.image = false             -- Enable the image module (boolean)
     t.modules.joystick = false          -- Enable the joystick module (boolean)
-    t.modules.keyboard = true           -- Enable the keyboard module (boolean)
+    t.modules.keyboard = false          -- Enable the keyboard module (boolean)
-    t.modules.math = true               -- Enable the math module (boolean)
+    t.modules.math = false              -- Enable the math module (boolean)
-    t.modules.mouse = true              -- Enable the mouse module (boolean)
+    t.modules.mouse = false              -- Enable the mouse module (boolean)
     t.modules.physics = false           -- Enable the physics module (boolean)
     t.modules.sound = false             -- Enable the sound module (boolean)
-    t.modules.system = true             -- Enable the system module (boolean)
+    t.modules.system = false             -- Enable the system module (boolean)
-    t.modules.thread = true             -- Enable the thread module (boolean)
+    t.modules.thread = false             -- Enable the thread module (boolean)
     t.modules.timer = true              -- Enable the timer module (boolean), Disabling it will result 0 delta time in love.update
     t.modules.touch = false             -- Enable the touch module (boolean)
     t.modules.video = false             -- Enable the video module (boolean)
-    t.modules.window = true             -- Enable the window module (boolean)
+    t.modules.window = false            -- Enable the window module (boolean)
 end

src/metaserver/main.lua

@@ -29,7 +29,7 @@ local handlers = setmetatable({
         --NAT punch: the server doesn't know its own external IP
         --so it contacts a third party (the metaserver) to discover it.
         --This external IP gets advertised to prospective clients.
-        svInfo.ip = shared.ip.fromString( ip )
+        svInfo.ip.ip = ip
         svInfo.port = port
       end
       servers[ip..port].time = t
@@ -57,7 +57,6 @@ local handlers = setmetatable({
       local t = socket.gettime()
       clients[ip].time = t
 
-      packet.heartbeat{ tick = tick }
       for svIP, server in pairs( servers ) do
         print( "", svIP, packet.getString( server.info.svname ))
         packet.serverInfo( server.info )

src/server/conf.lua

@@ -47,5 +47,5 @@ function love.conf(t)
     t.modules.timer = true              -- Enable the timer module (boolean), Disabling it will result 0 delta time in love.update
     t.modules.touch = false             -- Enable the touch module (boolean)
     t.modules.video = false             -- Enable the video module (boolean)
-    t.modules.window = true             -- Enable the window module (boolean)
+    t.modules.window = false            -- Enable the window module (boolean)
 end

src/server/main.lua

@@ -24,27 +24,48 @@ local server = { tick = 0, }
 
 local handlers = setmetatable({
 
+    connected = function( msg, ip, port )
+      local client = clients[msg.token]
+      if not client or
+      (client.ip ~= ip) or
+      (client.port ~= port)
+      then
+        print( "Invalid token from IP:", msg.token, ip, port )
+        return true
+      end
+
+      if client.tick > msg.tick then
+        print( "Old packet received:", msg.tick, ip )
+        return true
+      end
+
+      client.tick = msg.tick
+    end,
+
     clChimo = function( clChimo, ip, port )
-      if not connecting[ ip..port ] then
+      local key = ip..":"..port
-        return print( "Old connection attempt from:", ip, port )
+      if not connecting[ key ] then
+        print( "Old connection attempt from:", key )
+        return true
       end
       local remoteHash = clChimo.hash
       local clNonce = clChimo.nonce
-      local svNonce = connecting[ip..port].nonce
+      local svNonce = connecting[key].nonce
-      local localHash = shared.hash.hash( clNonce, svNonce )
+      local token = shared.hash.hash( clNonce, svNonce )
-      if localHash ~= remoteHash then
+      if token ~= remoteHash then
-        return print( "Hashes differ:", shared.hash.hex( clNonce ), shared.hash.hex( svNonce ) )
+        print( "Hashes differ:", shared.hash.hex( clNonce ), shared.hash.hex( svNonce ) )
+        return true
       end
-      print( "Client connected:", ip, port, localHash )
+      print( "Client connected:", ip, port, token )
-      clients[ localHash ] = { ip = ip, port = port }
+      clients[ token ] = connecting[ key ]
-      packet.connected{ token = localHash }
+      packet.connected{ token = token, tick = server.tick }
       return udp:sendto( packet.get(), ip, port )
     end,
 
     advertised = function( ack, ip, port )
       if ip ~= shared.metaserver.ip then return print( "Advertisement acked from rogue address:", ip, port ) end
       if udp:getsockname() then 
-        assert( udp:getsockname() == tostring( ack.ip ) )
+        --assert( udp:getsockname() == tostring( ack.ip ), print( tostring( ack.ip ), udp:getsockname()) or "IP mismatch!" )
         return print( "Advertised. Address already set." )
       end
       print( "Advertised. Setting address:", ack.ip, ack.port )
@@ -53,8 +74,8 @@ local handlers = setmetatable({
 
 
     clientInfo = function( clientInfo, ip, port )
-      local key = ip..port 
+      local key = ip..":"..port 
-      connecting[key] = connecting[key] or {}
+      connecting[key] = connecting[key] or { ip = ip, port = port, tick = 0 }
       local client = connecting[key]
       local nonce = shared.hash.rand()
       client.nonce = nonce
@@ -85,17 +106,16 @@ end
 
 --Incoming packet.
 function server.Parse( msg, ip, port )
-  if not msg then return end
+  if (not msg) or (#msg < 1) then return end
-  if not clients[ip] then
+  print( "Parsing:", ip, port, #msg, msg )
-    print( "New IP:", ip, port )
-    clients[ip] = { ip = ip, port = port }
-  end
-
   local msgs, types = packet.deserialise( msg )
-  if msgs then for i = 1, #msgs do
+  if msgs then
-    print( "Received: ", types[i], ip, port )
+    for i = 1, #msgs do
-    handlers[ types[i] ]( msgs[i], ip, port )
+      print( "Received: ", types[i], ip, port )
-  end end
+      if handlers[ types[i] ]( msgs[i], ip, port ) then break end
+    end
+  else print( types )
+  end
   return server.Parse( udp:receivefrom() ) -- Process other packets.
 end
 
@@ -124,8 +144,13 @@ end
 
 function server.Advance()
   server.tick = server.tick + 1
-  for id, client in pairs( clients ) do
+  if server.tick % 100 == 0 then
-    --
+    for id, client in pairs( clients ) do
+      packet.get()
+      print( "updating client:", id )
+      packet.connected{ token = id, tick = server.tick }
+      udp:sendto( packet.get(), client.ip, client.port )
+    end
   end
 end
 
@@ -142,7 +167,7 @@ server.Start()
 function love.update( dt )
   server.Parse( udp:receivefrom() )
   server.Advance()
-  if server.tick % 250 == 0 then
+  if server.tick % 4000 == 0 then
     server.Advertise()
     server.Parse( mscxn:receive(), shared.metaserver.ip, shared.metaserver.port )
   end

src/shared/hash.lua

@@ -1,6 +1,6 @@
 local math = math
 local bit = assert( require 'bit' )
-local max = bit.tobit( 0xffffffff )
+local max = math.huge
 math.randomseed( 4 )
 --hash of a pair of 32-bit numbers
 return { 

src/shared/ipstring.lua

@@ -1,30 +1,23 @@
+--CData structure that can hold the longest string representation of an IPv6 address
+--we do this because LuaSocket expects a Lua string, and because we can't guarantee v4-only addresses
 local ffi = assert( require 'ffi' )
 local ipString = {}
 local string = assert( string )
 ffi.cdef[[
   typedef struct {
-    uint8_t a;
+    char ip[40];
-    uint8_t b;
-    uint8_t c;
-    uint8_t d;
   } ipAddress;
 ]]
 
 local ipAddress = ffi.typeof( ffi.new( "ipAddress" ) )
-ffi.metatype( ipAddress, { __tostring = function( ip ) return ip.a.."."..ip.b.."."..ip.c.."."..ip.d end } )
+ffi.metatype( ipAddress, { __tostring = function( ip ) return ffi.string( ip.ip, ffi.sizeof( ip.ip ) ) end } )
 
 function ipString.new( t )
   local ip = ffi.new( ipAddress )
-  ip.a, ip.b, ip.c, ip.d = t[1], t[2], t[3], t[4]
+  ip.ip = t
   return ip
 end
 
-function ipString.fromString( s )
+ipString.fromString = ipString.new
-  local t = {}
-  for octet in s:gmatch( '%d+' ) do
-    table.insert( t, tonumber( octet ) )
-  end
-  return ipString.new( t )
-end
 
 return ipString

src/shared/packet.lua

@@ -51,6 +51,7 @@ newStruct{
 newStruct{
   name = "connected",
    "uint32_t  token",
+   "uint32_t  tick",
 }
 
 newStruct{
@@ -58,12 +59,6 @@ newStruct{
   "char   padding[300]" --Just a bunch of padding to mitigate amplification. 
 }
 
-newStruct{
-  name =  "heartbeat",
-  "uint32_t     tick",
-  "uint32_t     hash",
-}
-
 newStruct{
   name =  "insect",
   "uint8_t     id",
@@ -93,6 +88,7 @@ newStruct{
 
 newStruct{
   name = "chatMessage",
+  "uint8_t         id",
   "char     cmsg[127]",
 }
 
@@ -110,7 +106,7 @@ newStruct{
 
 newStruct{
   name = "disconnect",
-  "uint32_t   reason",
+  "char       reason",
 }
 
 local readBuffer = buffer.new( 1024 )
@@ -175,7 +171,7 @@ if testing then
     svname = "😘😘😘😘😘😘😘kissyfaceserver",
     version = 25,
     port = 51312,
-    ip = ipString.new{ 132, 213, 45, 21 }
+    ip = ipString.new '132.145.25.62'
   }
 
   packet.heartbeat{