First blood

pymaster.py

@@ -0,0 +1,116 @@
+import socket
+import random
+import struct
+import sys
+from server_entry import ServerEntry
+from util import getAttrOrNone
+
+UDP_IP = "127.0.0.1"
+UDP_PORT = 27010
+
+sock = []
+
+def logPrint( msg ):
+	if DEBUG:
+		print( msg )
+
+class PyMaster:
+	self.serverList = []
+	self.sock = []
+	
+	def __init__(self):
+		sock = socket.socket( socket.AF_INET, socket.SOCK_DGRAM )
+		sock.bind( (UDP_IP, UDP_PORT) )
+
+		logprint("Welcome to PyMaster!")
+		logprint("I ask you again, are you my master?")
+		logprint("Running on %s:%i" % UDP_IP, UDP_PORT)
+	
+	def serverLoop(self)
+		data, addr = sock.recvfrom(1024)4
+		logprint("received message: %s" % data)
+		
+		if data[0] == '1':
+			self.clientQuery(data, addr);
+		elif data[0] == 'q'
+			self.sendChallengeToServer(data, addr);
+		elif data[0] == '0'
+			self.addServerToList(data, addr);
+		elif data[0] == 'b'
+			self.removeServerFromList(data, addr);
+		else
+			logprint("Unknown message: %s from %s" % data, addr)
+
+	def clientQuery(self, data, addr):
+		data = data.strip('1')
+		
+		region = data[0]
+		queryAddr, rawFilter = data.split('\0')
+		
+		rawFilter = rawFilter.split('\\')
+		queryFilter = namedtuple('QueryFilter', rawFilter[0::2])._make(rawFilter[1::2])
+
+		#nor       = getAttrOrNone(queryFilter, 'nor')
+		#nand      = getAttrOrNone(queryFilter, 'nand')
+		#dedicated = getAttrOrNone(queryFilter, 'dedicated')
+		#gamedir   = getAttrOrNone(queryFilter, 'gamedir')
+		#gamemap   = getAttrOrNone(queryFilter, 'map')
+		#linux     = getAttrOrNone(queryFilter, 'linux')
+		#empty     = getAttrOrNone(queryFilter, 'empty')
+		#full      = getAttrOrNone(queryFilter, 'full')
+		#proxy     = getAttrOrNone(queryFilter, 'proxy')
+		#noplayers = getAttrOrNone(queryFilter, 'noplayers')
+		#white     = getAttrOrNone(queryFilter, 'white')
+		#name      = getAttrOrNone(queryFilter, 'name')
+		#version   = getAttrOrNone(queryFilter, 'version_match')
+		#gameaddr  = getAttrOrNone(queryFilter, 'gameaddr')
+		secure    = getAttrOrNone(queryFilter, 'secure')
+
+		packet = '\xff\xff\xff\xff\x66\x0a'
+		for i in self.serverList:
+			if( !i.check ):
+				continue
+			
+			if( gamedir != None ):
+				if( gamedir != i.serverInfo.gamedir):
+					continue
+			
+			# Use pregenerated address string
+			packet += self.queryAddr
+	
+	def sendChallengeToServer(self, data, addr):
+		# Generate a 32 bit challenge number
+		challenge = random.randint(0, 2**32-1)
+		
+		# Add server to list
+		self.serverList.append(ServerEntry(addr, challenge))
+		
+		# And send him a challenge
+		packet = '\xff\xff\xff\xff\x73\x0a'
+		packet += struct.pack('I', challenge)
+		socket.sendto(packet, addr)
+
+	def addServerToList(self, data, addr):
+		# Remove the header
+		serverInfo = data.strip('\x30\x0a\x5c')
+		
+		# Find a server with 
+		for serverEntry in self.serverList:
+			if (serverEntry.addr == addr):
+				serverEntry.setInfoString(serverInfo)
+	
+	def removeServerFromList(self, data, addr):
+		for i in self.serverList:
+			if (i.addr == addr):
+				self.serverList.remove(i)
+
+def main( argv = None ):
+	if argv is None:
+		argv = sys.argv
+	
+	masterMain = PyMaster()
+	while True: 
+		masterMain.serverLoop()
+
+if __name__ == "__main__":
+	sys.exit( main( ) )

server_entry.py

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+from collections import namedtuple
+from time import time
+
+class ServerEntry:
+	def setInfoString(self, data):
+		infostring = data.translate(None, '\n\r\0')
+		split = infostring.split('\\')
+		self.serverInfo = namedtuple('ServerInfo', split[0::2])._make(split[1::2])
+		self.check = int(self.serverInfo.challenge) == self.challenge
+
+	def __init__(self, addr, challenge):
+		# Address
+		self.addr = addr
+		
+		# Shortcuts for generating query
+		self.queryAddr = ""
+		for i in addr[0].split('.'):
+			self.queryAddr += struct.pack('B', int(i))
+		self.queryAddr += struct.pack('H', addr[1])
+		
+		# Random number that server must return 
+		self.challenge = challenge
+		
+		# This server is not checked
+		# So it will not get into queries
+		self.check = False
+		
+		# Remove server after this time.
+		# This maybe not instant
+		self.die = time() + 600.0

util.py

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+def getAttrOrNone(obj, prop):
+	return getattr(obj, prop, None)