From 788b7a11f50d26747e5cc512b6418a5074a52833 Mon Sep 17 00:00:00 2001
From: wan-may <wnmy@protonmail.com>
Date: Tue, 26 Sep 2023 18:56:24 -0300
Subject: [PATCH] Fixed bug introduced by null terminator inside IP string.
 Basic logic to disconnect clients.

---
 src/client/connecting.lua |  5 ++---
 src/client/game.lua       |  9 ++++++++-
 src/server/main.lua       | 29 +++++++++++++++++++++++++++--
 3 files changed, 37 insertions(+), 6 deletions(-)

diff --git a/src/client/connecting.lua b/src/client/connecting.lua
index e655c71..136ed48 100644
--- a/src/client/connecting.lua
+++ b/src/client/connecting.lua
@@ -29,9 +29,8 @@ end
 
 function connecting.draw()
   lg.setColor( 1,1,1,1 )
-  lg.printf( "CONNECTING\nADDRESS\nATTEMPTS",
-    15, 15, lg.getWidth() - 30, "left" )
-  lg.printf( ("\n%s:%d\n%d"):format( ip, port, attempts ), 15, 15, lg.getWidth() - 30, "right" )
+  lg.printf( ("ADDRESS: %s"):format( ip ), lg.getWidth() / 4, 15, lg.getWidth() - 30, "left" )
+  lg.printf( ("ATTEMPTS: %d"):format( attempts ), lg.getWidth() / 4, 20 + lg.getFont():getHeight(), lg.getWidth() - 30, "left" )
   cancelButton:draw()
   return false
 end
diff --git a/src/client/game.lua b/src/client/game.lua
index 30bdaa8..632ee2a 100644
--- a/src/client/game.lua
+++ b/src/client/game.lua
@@ -13,6 +13,7 @@ local serverTick = 0
 
 function handlers.connected( data )
   serverTick = math.max( data.tick, serverTick )
+  tick = math.max( serverTick, tick )
 end
 
 function handlers.insect( data )
@@ -40,7 +41,10 @@ end
 function game.onPacket( msg )
   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
+  if not msgs then 
+    print( "malformed packet:", types )
+    return game.onPacket( server.receive() )
+  end
   for i = 1, #msgs do
     --Handler returns something if msg should be discarded.
     if handlers[ types[i] ]( msgs[i] ) then break end
@@ -65,6 +69,9 @@ function game.newGame( )
 end
 
 function game.disconnect( )
+  server.newPacket()
+  server.disconnect()
+  server.send( packet.get() )
   return scene.mainmenu( server.disconnect() )
 end
 
diff --git a/src/server/main.lua b/src/server/main.lua
index 379cfe2..783fc12 100644
--- a/src/server/main.lua
+++ b/src/server/main.lua
@@ -20,10 +20,11 @@ local svInfo = packet.serverInfo{ version = 13,
 
 local clients = {}
 local connecting = {}
-local server = { tick = 0, }
+local server = { tick = 0, currentClient = false }
 
 local handlers = setmetatable({
 
+    --This is the start of a packet from a connected client.
     connected = function( msg, ip, port )
       local client = clients[msg.token]
       if not client or
@@ -40,8 +41,22 @@ local handlers = setmetatable({
       end
 
       client.tick = msg.tick
+      server.currentClient = client
+    end,
+    
+    --A client wants to disconnect.
+    disconnect = function( msg, ip, port )
+      --This is the authenticated client whose packets are being processed.
+      local client = server.currentClient
+      if client and client.ip == ip and client.port == port then
+        print( "Client disconnecting:", client.id)
+        clients[ client.id ] = nil
+        server.currentClient = false
+        return true
+      end
     end,
 
+    --Client responds to handshake challenge.
     clChimo = function( clChimo, ip, port )
       local key = ip..":"..port
       if not connecting[ key ] then
@@ -56,12 +71,16 @@ local handlers = setmetatable({
         print( "Hashes differ:", shared.hash.hex( clNonce ), shared.hash.hex( svNonce ) )
         return true
       end
+      
+      --Successful handshake.
       print( "Client connected:", ip, port, token )
       clients[ token ] = connecting[ key ]
+      clients[ token ].token = token
       packet.connected{ token = token, tick = server.tick }
       return udp:sendto( packet.get(), ip, port )
     end,
 
+    --Metaserver replying with real IP address.
     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 
@@ -72,7 +91,7 @@ local handlers = setmetatable({
       server.SetIP( tostring( ack.ip ), ack.port )
     end,
 
-
+    --New client seeks to connect. Challenge immediately.
     clientInfo = function( clientInfo, ip, port )
       local key = ip..":"..port 
       connecting[key] = connecting[key] or { ip = ip, port = port, tick = 0 }
@@ -114,6 +133,7 @@ function server.Parse( msg, ip, port )
       print( "Received: ", types[i], ip, port )
       if handlers[ types[i] ]( msgs[i], ip, port ) then break end
     end
+    server.currentClient = false
   else print( types )
   end
   return server.Parse( udp:receivefrom() ) -- Process other packets.
@@ -150,6 +170,11 @@ function server.Advance()
       print( "updating client:", id )
       packet.connected{ token = id, tick = server.tick }
       udp:sendto( packet.get(), client.ip, client.port )
+      
+      if server.tick - client.tick > 1000 then
+        print( "dropping client:", id )
+        clients[id] = nil
+      end
     end
   end
 end