fail2ban-client

#!/usr/bin/env python
# This file is part of Fail2Ban.
#
# Fail2Ban is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# Fail2Ban is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Fail2Ban; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

# Author: Cyril Jaquier
# 
# $Revision$

__author__ = "Cyril Jaquier"
__version__ = "$Revision$"
__date__ = "$Date$"
__copyright__ = "Copyright (c) 2004 Cyril Jaquier"
__license__ = "GPL"

import sys, string, os, pickle, re, logging
import getopt, time, readline, shlex, socket

# Inserts our own modules path first in the list
# fix for bug #343821
sys.path.insert(1, "/usr/lib/fail2ban")

# Now we can import our modules
from version import version
from client.csocket import CSocket
from client.configurator import Configurator
from client.beautifier import Beautifier

# Gets the instance of the logger.
logSys = logging.getLogger("fail2ban.client")

##
#
# @todo This class needs cleanup.

class Fail2banClient:

	prompt = "fail2ban> "

	def __init__(self):
		self.__argv = None
		self.__stream = None
		self.__conf = dict()
		self.__conf["conf"] = "/etc/fail2ban"
		self.__conf["dump"] = False
		self.__conf["force"] = False
		self.__conf["verbose"] = 2
		self.__conf["interactive"] = False
		
	def dispVersion(self):
		print "Fail2Ban v" + version
		print
		print "Copyright (c) 2004-2006 Cyril Jaquier"
		print "Copyright of modifications held by their respective authors."
		print "Licensed under the GNU General Public License v2 (GPL)."
		print
		print "Written by Cyril Jaquier <lostcontrol@users.sourceforge.net>."
		print "Many contributions by Yaroslav O. Halchenko <debian@onerussian.com>."
	
	def dispUsage(self):
		""" Prints Fail2Ban command line options and exits
		"""
		print "Usage: "+self.__argv[0]+" [OPTIONS]... <COMMAND>"
		print
		print "Fail2Ban v" + version + " reads log file that contains password failure report"
		print "and bans the corresponding IP addresses using firewall rules."
		print
		print "Options:"
		print "    -c <DIR>                configuration directory"
		print "    -d                      dump configuration. For debugging"
		print "    -i                      interactive mode"
		print "    -v                      increase verbosity"
		print "    -q                      decrease verbosity"
		print "    -x                      force execution of the server"
		print "    -h, --help              display this help message"
		print "    -V, --version           print the version"
		print
		print "Command:"
		print "    start                   start the server and the jails"
		print "    reload                  reload the configuration"
		print "    stop                    stop all jails and terminate the server"
		print "    status                  get the current status"
		print
		print "    set loglevel <LEVEL>    set loglevel to <LEVEL>"
		print "    get loglevel            get loglevel"
		print "    set logtarget <TARGET>  set log target to <TARGET>"
		print "    get logtarget           get log target"
		print
		print "    add <JAIL>              create <JAIL>"
		print "    set <JAIL> <CMD>        set the <CMD> value for <JAIL>"
		print "    get <JAIL> <CMD>        get the <CMD> value for <JAIL>"
		print "    start <JAIL>            start <JAIL>"
		print "    stop <JAIL>             stop <JAIL>. The jail is removed"
		print "    status <JAIL>           get the current status of <JAIL>"
		print
		print "Report bugs to <lostcontrol@users.sourceforge.net>"
	
	def dispInteractive(self):
		print "Fail2Ban v" + version + " reads log file that contains password failure report"
		print "and bans the corresponding IP addresses using firewall rules."
		print 
	
	def __getCmdLineOptions(self, optList):
		""" Gets the command line options
		"""
		for opt in optList:
			if opt[0] == "-c":
				self.__conf["conf"] = opt[1]
			elif opt[0] == "-d":
				self.__conf["dump"] = True
			elif opt[0] == "-v":
				self.__conf["verbose"] = self.__conf["verbose"] + 1
			elif opt[0] == "-q":
				self.__conf["verbose"] = self.__conf["verbose"] - 1
			elif opt[0] == "-x":
				self.__conf["force"] = True
			elif opt[0] == "-i":
				self.__conf["interactive"] = True
			elif opt[0] in ["-h", "--help"]:
	 			self.dispUsage()
	 			sys.exit(0)
	 		elif opt[0] in ["-V", "--version"]:
	 			self.dispVersion()
	 			sys.exit(0)
	
	def __ping(self):
		return self.processCmd([["ping"]], False)
	
	@staticmethod
	def processCmd(cmd, showRet = True):
		beautifier = Beautifier()
		for c in cmd:
			beautifier.setInputCmd(c)
			try:
				client = CSocket()
				ret = client.send(c)
				if ret[0] == 0:
					logSys.debug("OK : " + `ret[1]`)
					if showRet:
						print beautifier.beautify(ret[1])
				else:
					logSys.debug("NOK: " + `ret[1].args`)
					print beautifier.beautifyError(ret[1])
					return False
			except socket.error:
				if showRet:
					logSys.error("Unable to contact server. Is it running?")
				return False
			except Exception, e:
				if showRet:
					logSys.error(e)
				return False
		return True
		
	##
	# Process a command line.
	#
	# Process one command line and exit.
	# @param cmd the command line

	def __processCommand(self, cmd):
		if len(cmd) == 1 and cmd[0] == "start":
			if self.__ping():
				logSys.info("Server already running")
				return False
			else:
				self.__startServerAsync(self.__conf["force"])
				# Read the config while the server is starting
				self.__readConfig()
				try:
					# Wait for the server to start
					self.__waitOnServer()
					# Configure the server
					self.processCmd(self.__stream, False)
					return True
				except ServerExecutionException:
					logSys.error("Could not start server. Try -x option")
					return False
		elif len(cmd) == 1 and cmd[0] == "reload":
			if self.__ping():
				self.__readConfig()
				self.processCmd([['stop', 'all']], False)
				# Configure the server
				return self.processCmd(self.__stream, False)
			else:
				logSys.error("Could not find server")
				return False
		else:
			return self.processCmd([cmd])
	
	
	##
	# Start Fail2Ban server.
	#
	# Start the Fail2ban server in daemon mode.
	
	def __startServerAsync(self, force = False):
		args = list()
		
		args.append("fail2ban-server")
		args.append("-b")
		if force:
			args.append("-x")
		
		pid = os.fork()
		if pid == 0:
			try:
				# Use the PATH env
				os.execvp("fail2ban-server", args)
			except OSError:
				try:
					# Use the current directory
					os.execv("fail2ban-server", args)
				except OSError:
					print "Could not find fail2ban-server"
					os.exit(-1)
						
			
	def __waitOnServer(self):
		# Wait for the server to start
		cnt = 0
		while not self.__ping():
			if cnt > 10:
				raise ServerExecutionException("Failed to start server")
			time.sleep(0.1)
			cnt = cnt + 1
			
	
	def start(self, argv):
		# Command line options
		self.__argv = argv
		
		# Reads the command line options.
		try:
			cmdOpts = 'hc:xdviqV'
			cmdLongOpts = ['help', 'version']
			optList, args = getopt.getopt(self.__argv[1:], cmdOpts, cmdLongOpts)
		except getopt.GetoptError:
			self.dispUsage()
			return False
			
		self.__getCmdLineOptions(optList)
		
		verbose = self.__conf["verbose"]
		if verbose <= 0:
			logSys.setLevel(logging.ERROR)
		elif verbose == 1:
			logSys.setLevel(logging.WARN)
		elif verbose == 2:
			logSys.setLevel(logging.INFO)
		else:
			logSys.setLevel(logging.DEBUG)
		# Add the default logging handler
		stdout = logging.StreamHandler(sys.stdout)
		# set a format which is simpler for console use
		formatter = logging.Formatter('%(levelname)-6s %(message)s')
		# tell the handler to use this format
		stdout.setFormatter(formatter)
		logSys.addHandler(stdout)

		if self.__conf["dump"]:
			self.__readConfig()
			self.dumpConfig(self.__stream)
			return True
		
		# Interactive mode
		if self.__conf["interactive"]:
			try:
				ret = True
				if len(args) > 0:
					ret = self.__processCommand(args)
				if ret:
					readline.parse_and_bind("tab: complete")
					self.dispInteractive()
					while True:
						cmd = raw_input(self.prompt)
						if cmd == "exit" or cmd == "quit":
							# Exit
							return True
						if not cmd == "":
							self.__processCommand(shlex.split(cmd))
			except (EOFError, KeyboardInterrupt):
				print
				return True
		# Single command mode
		else:
			if len(args) < 1:
				self.dispUsage()
				return False
			return self.__processCommand(args)

	def __readConfig(self):
		# Read the configuration
		cfg = Configurator()
		cfg.setBaseDir(self.__conf["conf"])
		cfg.readAll()
		cfg.getAllOptions()
		cfg.convertToProtocol()
		self.__stream = cfg.getConfigStream()
	
	@staticmethod
	def dumpConfig(cmd):
		for c in cmd:
			print c
		return True


class ServerExecutionException(Exception):
	pass

if __name__ == "__main__":
	client = Fail2banClient()
	# Exit with correct return value
	if client.start(sys.argv):
		sys.exit(0)
	else:
		sys.exit(-1)