- Fixed startup and daemon mode

git-svn-id: https://fail2ban.svn.sourceforge.net/svnroot/fail2ban/trunk@300 a942ae1a-1317-0410-a47c-b1dcaea8d605

fail2ban-server

@@ -101,20 +101,18 @@ class Fail2banServer:
 			
 		self.getCmdLineOptions(optList)
 		
-		if self.conf["background"]:
-			retCode = createDaemon()
-			#signal.signal(signal.SIGTERM, sigTERMhandler)
-			if not retCode:
-				print "Unable to start daemon"
-				sys.exit(-1)
-		
 		try:
-			self.server = Server()
+			self.server = Server(self.conf["background"])
 			self.server.start(self.conf["force"])
+			return True
 		except Exception, e:
 			print e
 			self.server.quit()
+			return False
 		
 if __name__ == "__main__":
 	server = Fail2banServer()
-	server.start(sys.argv)
+	if server.start(sys.argv):
+		sys.exit(0)
+	else:
+		sys.exit(-1)

server/server.py

@@ -26,15 +26,16 @@ __license__ = "GPL"
 
 from jail import Jail
 from transmitter import Transmitter
-import locale, logging, sys
+import locale, logging, sys, os, signal
 
 # Gets the instance of the logger.
 logSys = logging.getLogger("fail2ban.server")
 
 class Server:
 	
-	def __init__(self):
+	def __init__(self, daemon = False):
 		self.jails = dict()
+		self.daemon = daemon
 		self.transm = Transmitter(self)
 		self.logLevel = 3
 		self.logTarget = "STDERR"
@@ -43,8 +44,18 @@ class Server:
 		self.setLogTarget(self.logTarget)
 	
 	def start(self, force):
+		logSys.info("Starting Fail2ban")
+		if self.daemon:
+			ret = self.createDaemon()
+			if ret:
+				logSys.info("Daemon started")
+			else:
+				logSys.error("Could not create daemon")
+				raise ServerInitializationError("Could not create daemon")
 		# Start the communication
+		logSys.debug("Starting communication")
 		self.transm.start(force)
+		logSys.info("Exiting Fail2ban")
 	
 	def quit(self):
 		self.stopAllJail()
@@ -354,6 +365,82 @@ class Server:
 	
 	def getLogTarget(self):
 		return self.logTarget
+	
+	def createDaemon(self):
+		""" Detach a process from the controlling terminal and run it in the
+			background as a daemon.
+		
+			http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/278731
+		"""
+	
+		try:
+			# Fork a child process so the parent can exit.  This will return control
+			# to the command line or shell.  This is required so that the new process
+			# is guaranteed not to be a process group leader.  We have this guarantee
+			# because the process GID of the parent is inherited by the child, but
+			# the child gets a new PID, making it impossible for its PID to equal its
+			# PGID.
+			pid = os.fork()
+		except OSError, e:
+			return((e.errno, e.strerror))	 # ERROR (return a tuple)
+		
+		if pid == 0:	   # The first child.
+	
+			# Next we call os.setsid() to become the session leader of this new
+			# session.  The process also becomes the process group leader of the
+			# new process group.  Since a controlling terminal is associated with a
+			# session, and this new session has not yet acquired a controlling
+			# terminal our process now has no controlling terminal.  This shouldn't
+			# fail, since we're guaranteed that the child is not a process group
+			# leader.
+			os.setsid()
+		
+			# When the first child terminates, all processes in the second child
+			# are sent a SIGHUP, so it's ignored.
+			signal.signal(signal.SIGHUP, signal.SIG_IGN)
+		
+			try:
+				# Fork a second child to prevent zombies.  Since the first child is
+				# a session leader without a controlling terminal, it's possible for
+				# it to acquire one by opening a terminal in the future.  This second
+				# fork guarantees that the child is no longer a session leader, thus
+				# preventing the daemon from ever acquiring a controlling terminal.
+				pid = os.fork()		# Fork a second child.
+			except OSError, e:
+				return((e.errno, e.strerror))  # ERROR (return a tuple)
+		
+			if (pid == 0):	  # The second child.
+				# Ensure that the daemon doesn't keep any directory in use.  Failure
+				# to do this could make a filesystem unmountable.
+				os.chdir("/")
+			else:
+				os._exit(0)	  # Exit parent (the first child) of the second child.
+		else:
+			os._exit(0)		 # Exit parent of the first child.
+		
+		# Close all open files.  Try the system configuration variable, SC_OPEN_MAX,
+		# for the maximum number of open files to close.  If it doesn't exist, use
+		# the default value (configurable).
+		try:
+			maxfd = os.sysconf("SC_OPEN_MAX")
+		except (AttributeError, ValueError):
+			maxfd = 256	   # default maximum
+	
+		for fd in range(0, maxfd):
+			try:
+				os.close(fd)
+			except OSError:   # ERROR (ignore)
+				pass
+	
+		# Redirect the standard file descriptors to /dev/null.
+	   	os.open("/dev/null", os.O_RDONLY)	# standard input (0)
+		os.open("/dev/null", os.O_RDWR)		# standard output (1)
+		os.open("/dev/null", os.O_RDWR)		# standard error (2)
+		return True
+
 
 class ServerUnknownJail(Exception):
+	pass
+
+class ServerInitializationError(Exception):
 	pass

server/transmitter.py

@@ -37,10 +37,16 @@ class Transmitter:
 		self.server = server
 		self.socket = SSocket(self)
 	
+	##
+	# Start the transmittion server.
+	#
+	# This function wait for the socket thread.
+	
 	def start(self, force):
 		try:
 			self.socket.initialize(force)
 			self.socket.start()
+			self.socket.join()
 		except SSocketErrorException:
 			logSys.error("Could not start server")
 	
@@ -61,7 +67,7 @@ class Transmitter:
 			ret = self.actionHandler(action)
 			ack = 0, ret
 		except Exception, e:
-			logSys.warn("Invalid command")
+			logSys.warn("Invalid command: " + `action`)
 			ack = 1, e
 		return ack