diff --git a/pymaster.py b/pymaster.py index 04fc018..949823c 100755 --- a/pymaster.py +++ b/pymaster.py @@ -6,103 +6,157 @@ import traceback import logging import os from optparse import OptionParser -from struct import pack +from struct import pack, unpack from time import time +from ipaddress import ip_address, ip_network from server_entry import ServerEntry from protocol import MasterProtocol +import ipfilter LOG_FILENAME = 'pymaster.log' MAX_SERVERS_FOR_IP = 14 +CHALLENGE_SEND_PERIOD = 10 -def logPrint( msg ): - logging.debug( msg ) +def log(msg): + logging.debug(msg) + +class RateLimitItem: + def __init__(self, resetAt): + self.reset(resetAt) + + def reset(self, resetAt): + self.resetAt = resetAt + self.logs = self.calls = 0 + + def inc(self): + self.calls = self.calls + 1 + self.logs = self.logs + 1 + + def shouldReset(self, curtime): + return curtime > self.resetAt + +class IPRateLimit: + def __init__(self, type, period, maxcalls): + self.type = type + self.period = period + self.maxcalls = maxcalls + self.maxlogs = maxcalls + 2 + self.ips = {} + + def ratelimit(self, ip): + curtime = time() + + if ip not in self.ips: + self.ips[ip] = RateLimitItem(curtime + self.period) + elif self.ips[ip].shouldReset(curtime): + self.ips[ip].reset(curtime + self.period) + + self.ips[ip].inc() + + if self.ips[ip].calls > self.maxcalls: + if self.ips[ip].logs < self.maxlogs: + log('Ratelimited %s %s' % (self.type, ip)) + return True + + return False class PyMaster: def __init__(self, ip, port): self.serverList = [] - self.sock = socket.socket( socket.AF_INET, socket.SOCK_DGRAM ) - self.sock.bind( (ip, port) ) + self.serverRL = IPRateLimit('server', 60, 30) + self.clientRL = IPRateLimit('client', 60, 120) + self.ipfilterRL = IPRateLimit('filterlog', 60, 10) + self.sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) + self.sock.bind((ip, port)) - logPrint("Welcome to PyMaster!") - logPrint("I ask you again, are you my master?") - logPrint("Running on %s:%d" % (ip, port)) + log("Welcome to PyMaster!") + log("I ask you again, are you my master?") + log("Running on %s:%d" % (ip, port)) def serverLoop(self): data, addr = self.sock.recvfrom(1024) - data = data.decode('latin_1') - if( data[0] == MasterProtocol.clientQuery ): - self.clientQuery(data, addr) - elif( data[0] == MasterProtocol.challengeRequest ): - self.sendChallengeToServer(data, addr) - elif( data[0] == MasterProtocol.addServer ): - self.addServerToList(data, addr) - elif( data[0] == MasterProtocol.removeServer ): - self.removeServerFromList(data, addr) - else: - logPrint("Unknown message: {0} from {1}:{2}".format(data, addr[0], addr[1])) - - def clientQuery(self, data, addr): - region = data[1] # UNUSED - data = data.strip('1' + region) - try: - query = data.split('\0') - except ValueError: - logPrint(traceback.format_exc()) + if ip_address(addr[0]) in ipfilter.ipfilter: + if not self.ipfilterRL.ratelimit(addr[0]): + log('Filter: %s:%d' % (addr[0], addr[1])) return - queryAddr = query[0] # UNUSED - rawFilter = query[1] + if len(data) == 0: + return - # Remove first \ character - rawFilter = rawFilter.strip('\\') - split = rawFilter.split('\\') + # only client stuff + if data.startswith(MasterProtocol.clientQuery): + if not self.clientRL.ratelimit(addr[0]): + self.clientQuery(data, addr) + return - # Use NoneType as undefined - gamedir = 'valve' # halflife, by default - clver = None - nat = 0 + # only server stuff + if not self.serverRL.ratelimit(addr[0]): + if data.startswith(MasterProtocol.challengeRequest): + self.sendChallengeToServer(data, addr) + elif data.startswith(MasterProtocol.addServer): + self.addServerToList(data, addr) + elif data.startswith(MasterProtocol.removeServer): + self.removeServerFromList(data, addr) + else: + log('Unknown message: %s from %s:%d' % (str(data), addr[0], addr[1])) - for i in range( 0, len(split), 2 ): + def clientQuery(self, data, addr): + data = data.decode('latin_1') + data = data.strip('1' + data[1]) + info = data.split('\0')[1].strip('\\') + split = info.split('\\') + + protocol = None + gamedir = 'valve' + clver = None + nat = 0 + + for i in range(0, len(split), 2): try: - key = split[i + 1] - if( split[i] == 'gamedir' ): - gamedir = key.lower() # keep gamedir in lowercase - elif( split[i] == 'nat' ): - nat = int(key) - elif( split[i] == 'clver' ): - clver = key + k = split[i] + v = split[i + 1] + if k == 'gamedir': + gamedir = v.lower() # keep gamedir in lowercase + elif k == 'nat': + nat = int(v) + elif k == 'clver': + clver = v + elif k == 'protocol': + protocol = int(v) + # somebody is playing :) + elif k == 'thisismypcid' or k == 'heydevelopersifyoureadthis': + self.fakeInfoForOldVersions(gamedir, addr) + return else: - logPrint('Unhandled info string entry: {0}/{1}. Infostring was: {2}'.format(split[i], key, split)) + log('Client Query: %s:%d, invalid infostring=%s' % (addr[0], addr[1], rawFilter)) except IndexError: pass if( clver == None ): # Probably an old vulnerable version - self.fakeInfoForOldVersions( gamedir, addr ) + self.fakeInfoForOldVersions(gamedir, addr) return packet = MasterProtocol.queryPacketHeader for i in self.serverList: - if( time() > i.die ): + if time() > i.die: self.serverList.remove(i) continue - if( not i.check ): + if not i.check: continue - if( nat != i.nat ): + if nat != i.nat or gamedir != i.gamedir: continue - if( gamedir != None ): - if( gamedir != i.gamedir ): - continue + if protocol != None and protocol != i.protocol: + continue - if( nat ): - reply = '\xff\xff\xff\xffc {0}:{1}'.format( addr[0], addr[1] ) - data = reply.encode( 'latin_1' ) + if nat: # Tell server to send info reply - self.sock.sendto( data, i.addr ) + data = ('\xff\xff\xff\xffc %s:%d' % (addr[0], addr[1])).encode('latin_1') + self.sock.sendto(data, i.addr) # Use pregenerated address string packet += i.queryAddr @@ -124,53 +178,65 @@ class PyMaster: sendFakeInfo(self.sock, "GooglePlay или GitHub", gamedir, addr) def removeServerFromList(self, data, addr): - for i in self.serverList: - if (i.addr == addr): - logPrint("Remove Server: from {0}:{1}".format(addr[0], addr[1])) - self.serverList.remove(i) + pass def sendChallengeToServer(self, data, addr): - logPrint("Challenge Request: from {0}:{1}".format(addr[0], addr[1])) - # At first, remove old server- data from list - #self.removeServerFromList(None, addr) - count = 0 + s = None for i in self.serverList: - if ( i.addr[0] == addr[0] ): - if( i.addr[1] == addr[1] ): - self.serverList.remove(i) - else: - count += 1 - if( count > MAX_SERVERS_FOR_IP ): + if addr[0] != i.addr[0]: + continue + if addr[1] == i.addr[1]: + s = i + break + else: + count += 1 + if count > MAX_SERVERS_FOR_IP: return - # Generate a 32 bit challenge number - challenge = random.randint(0, 2**32-1) + challenge2 = None + if len(data) == 6: + # little endian challenge + challenge2 = unpack(' time(): + return - # And send him a challenge packet = MasterProtocol.challengePacketHeader - packet += pack('I', challenge) + packet += pack('I', s.challenge) + + # send server-to-master challenge back + if challenge2 is not None: + packet += pack('I', challenge2) + self.sock.sendto(packet, addr) def addServerToList(self, data, addr): - logPrint("Add Server: from {0}:{1}".format(addr[0], addr[1])) # Remove the header. Just for better parsing. - serverInfo = data.strip('\x30\x0a\x5c') + info = data.strip(b'\x30\x0a\x5c').decode('latin_1') # Find a server with same address - for serverEntry in self.serverList: - if( serverEntry.addr == addr ): + s = None + for s in self.serverList: + if s.addr == addr: break + if not s: + log('Server skipped challenge request: %s:%d' % (addr[0], addr[1])) + return - serverEntry.setInfoString( serverInfo ) + if s.setInfoString( info ): + log('Add server: %s:%d, game=%s/%s, protocol=%d, players=%d/%d/%d, version=%s' % (addr[0], addr[1], s.gamemap, s.gamedir, s.protocol, s.players, s.bots, s.maxplayers, s.version)) + else: + log('Failed challenge from %s:%d: %d must be %d' % (addr[0], addr[1], s.challenge, s.challenge2)) def spawn_pymaster(verbose, ip, port): if verbose: logging.getLogger().addHandler(logging.StreamHandler()) - logging.getLogger().addHandler(logging.FileHandler(LOG_FILENAME)) +# logging.getLogger().addHandler(logging.FileHandler(LOG_FILENAME)) logging.getLogger().setLevel(logging.DEBUG) masterMain = PyMaster(ip, port) @@ -178,7 +244,7 @@ def spawn_pymaster(verbose, ip, port): try: masterMain.serverLoop() except Exception: - logPrint(traceback.format_exc()) + log(traceback.format_exc()) pass if __name__ == "__main__":