mirror of https://github.com/fail2ban/fail2ban
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
552 lines
16 KiB
552 lines
16 KiB
#!/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 time, sys, getopt, os, signal, string
|
|
from ConfigParser import *
|
|
|
|
# Checks if log4py is present.
|
|
try:
|
|
import log4py
|
|
except:
|
|
print "log4py is needed (see README)"
|
|
sys.exit(-1)
|
|
|
|
# Appends our own modules path
|
|
sys.path.append('/usr/lib/fail2ban')
|
|
|
|
from firewall.iptables import Iptables
|
|
from firewall.ipfw import Ipfw
|
|
from firewall.ipfwadm import Ipfwadm
|
|
from logreader.logreader import LogReader
|
|
from confreader.configreader import ConfigReader
|
|
from version import version
|
|
|
|
def usage():
|
|
print "Usage: fail2ban.py [OPTIONS]"
|
|
print
|
|
print "Fail2Ban v"+version+" reads log file that contains password failure report"
|
|
print "and bans the corresponding IP address using iptables."
|
|
print
|
|
print " -b start fail2ban in background"
|
|
print " -d start fail2ban in debug mode"
|
|
print " -e <INTF> ban IP on the INTF interface"
|
|
print " -c <FILE> read configuration file FILE"
|
|
print " -p <FILE> create PID lock in FILE"
|
|
print " -h display this help message"
|
|
print " -i <IP(s)> IP(s) to ignore"
|
|
print " -k kill a currently running Fail2Ban instance"
|
|
print " -l <FILE> log message in FILE"
|
|
print " -r <VALUE> allow a max of VALUE password failure"
|
|
print " -t <TIME> ban IP for TIME seconds"
|
|
print " -v verbose. Use twice for greater effect"
|
|
print " -w <FIWA> select the firewall to use. Can be iptables,"
|
|
print " ipfwadm or ipfw"
|
|
print
|
|
print "Report bugs to <lostcontrol@users.sourceforge.net>"
|
|
sys.exit(0)
|
|
|
|
def checkForRoot():
|
|
""" Check for root user.
|
|
"""
|
|
uid = `os.getuid()`
|
|
if uid == '0':
|
|
return True
|
|
else:
|
|
return False
|
|
|
|
def createDaemon():
|
|
"""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("/")
|
|
# Give the child complete control over permissions.
|
|
os.umask(0)
|
|
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
|
|
|
|
def sigTERMhandler(signum, frame):
|
|
""" Handles the TERM signal when in daemon mode in order to
|
|
exit properly.
|
|
"""
|
|
logSys.debug("Signal handler called with sig "+`signum`)
|
|
killApp()
|
|
|
|
def killApp():
|
|
""" Flush the ban list, remove the PID lock file and exit
|
|
nicely.
|
|
"""
|
|
logSys.warn("Restoring firewall rules...")
|
|
fireWall.flushBanList(conf["debug"])
|
|
removePID(conf["pidlock"])
|
|
logSys.info("Exiting...")
|
|
sys.exit(0)
|
|
|
|
def checkForPID(lockfile):
|
|
""" Checks for running Fail2Ban.
|
|
|
|
Returns the current PID if Fail2Ban is running or False
|
|
if no instance found.
|
|
"""
|
|
try:
|
|
fileHandler = open(lockfile)
|
|
pid = fileHandler.readline()
|
|
return pid
|
|
except IOError:
|
|
return False
|
|
|
|
def createPID(lockfile):
|
|
""" Creates a PID lock file with the current PID.
|
|
"""
|
|
fileHandler = open(lockfile, mode='w')
|
|
pid = os.getpid()
|
|
fileHandler.write(`pid`+'\n')
|
|
fileHandler.close()
|
|
logSys.debug("Created PID lock ("+`pid`+") in "+lockfile)
|
|
|
|
def removePID(lockfile):
|
|
""" Remove PID lock.
|
|
"""
|
|
os.remove(lockfile)
|
|
logSys.debug("Removed PID lock "+lockfile)
|
|
|
|
def killPID(pid):
|
|
""" Kills the process with the given PID using the
|
|
INT signal (same effect as <ctrl>+<c>).
|
|
"""
|
|
try:
|
|
return os.kill(pid, 2)
|
|
except OSError:
|
|
logSys.error("Can not kill process " + `pid` + ". Please check that " +
|
|
"Fail2Ban is not running and remove the file " +
|
|
"'/tmp/fail2ban.pid'")
|
|
|
|
if __name__ == "__main__":
|
|
|
|
# Gets an instance of log4py.
|
|
logSys = log4py.Logger().get_instance()
|
|
logSys.set_formatstring("%T %L %M")
|
|
|
|
conf = dict()
|
|
conf["verbose"] = 0
|
|
conf["background"] = False
|
|
conf["debug"] = False
|
|
conf["conffile"] = "/etc/fail2ban.conf"
|
|
conf["pidlock"] = "/tmp/fail2ban.pid"
|
|
conf["logging"] = False
|
|
conf["logfile"] = "/var/log/fail2ban.log"
|
|
conf["maxretry"] = 3
|
|
conf["bantime"] = 600
|
|
conf["ignoreip"] = ''
|
|
conf["interface"] = "eth0"
|
|
conf["firewall"] = "iptables"
|
|
conf["ipfw-start-rule"] = 0
|
|
conf["polltime"] = 1
|
|
|
|
# Reads the command line options.
|
|
try:
|
|
optList, args = getopt.getopt(sys.argv[1:], 'hvbdkc:l:t:i:r:e:w:p:')
|
|
except getopt.GetoptError:
|
|
usage()
|
|
|
|
# Pre-parsing of command line options for the -c option
|
|
for opt in optList:
|
|
if opt[0] == "-c":
|
|
conf["conffile"] = opt[1]
|
|
|
|
# Config file
|
|
configParser = SafeConfigParser()
|
|
configParser.read(conf["conffile"])
|
|
|
|
# background
|
|
try:
|
|
conf["background"] = configParser.getboolean("DEFAULT", "background")
|
|
except ValueError:
|
|
logSys.warn("background option should be a boolean")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("background option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
# debug
|
|
try:
|
|
conf["debug"] = configParser.getboolean("DEFAULT", "debug")
|
|
except ValueError:
|
|
logSys.warn("debug option should be a boolean")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("debug option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
# logfile
|
|
try:
|
|
conf["logfile"] = configParser.get("DEFAULT", "logfile")
|
|
except ValueError:
|
|
logSys.warn("logfile option should be a string")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("logfile option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
# pidlock
|
|
try:
|
|
conf["pidlock"] = configParser.get("DEFAULT", "pidlock")
|
|
except ValueError:
|
|
logSys.warn("pidlock option should be a string")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("pidlock option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
# maxretry
|
|
try:
|
|
conf["maxretry"] = configParser.getint("DEFAULT", "maxretry")
|
|
except ValueError:
|
|
logSys.warn("maxretry option should be an integer")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("maxretry option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
# bantime
|
|
try:
|
|
conf["bantime"] = configParser.getint("DEFAULT", "bantime")
|
|
except ValueError:
|
|
logSys.warn("bantime option should be an integer")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("bantime option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
# ignoreip
|
|
try:
|
|
conf["ignoreip"] = configParser.get("DEFAULT", "ignoreip")
|
|
except ValueError:
|
|
logSys.warn("ignoreip option should be a string")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("ignoreip option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
# interface
|
|
try:
|
|
conf["interface"] = configParser.get("DEFAULT", "interface")
|
|
except ValueError:
|
|
logSys.warn("interface option should be a string")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("interface option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
# firewall
|
|
try:
|
|
conf["firewall"] = configParser.get("DEFAULT", "firewall")
|
|
except ValueError:
|
|
logSys.warn("firewall option should be a string")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("firewall option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
# ipfw-start-rule
|
|
try:
|
|
conf["ipfw-start-rule"] = configParser.getint("DEFAULT",
|
|
"ipfw-start-rule")
|
|
except ValueError:
|
|
logSys.warn("ipfw-start-rule option should be an integer")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("ipfw-start-rule option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
# polltime
|
|
try:
|
|
conf["polltime"] = configParser.getint("DEFAULT", "polltime")
|
|
except ValueError:
|
|
logSys.warn("polltime option should be an integer")
|
|
logSys.warn("Using default value")
|
|
except NoOptionError:
|
|
logSys.warn("polltime option not in config file")
|
|
logSys.warn("Using default value")
|
|
|
|
for opt in optList:
|
|
if opt[0] == "-h":
|
|
usage()
|
|
if opt[0] == "-v":
|
|
conf["verbose"] = conf["verbose"] + 1
|
|
if opt[0] == "-b":
|
|
conf["background"] = True
|
|
if opt[0] == "-d":
|
|
conf["debug"] = True
|
|
if opt[0] == "-e":
|
|
conf["interface"] = opt[1]
|
|
if opt[0] == "-l":
|
|
conf["logging"] = True
|
|
conf["logfile"] = opt[1]
|
|
if opt[0] == "-t":
|
|
try:
|
|
conf["bantime"] = int(opt[1])
|
|
except ValueError:
|
|
logSys.warn("banTime must be an integer")
|
|
logSys.warn("Using default value")
|
|
if opt[0] == "-i":
|
|
conf["ignoreip"] = opt[1]
|
|
if opt[0] == "-r":
|
|
conf["retrymax"] = int(opt[1])
|
|
if opt[0] == "-w":
|
|
conf["firewall"] = opt[1]
|
|
if opt[0] == "-p":
|
|
conf["pidlock"] = opt[1]
|
|
if opt[0] == "-k":
|
|
pid = checkForPID(conf["pidlock"])
|
|
if pid:
|
|
killPID(int(pid))
|
|
logSys.warn("Killed Fail2Ban with PID "+pid)
|
|
sys.exit(0)
|
|
else:
|
|
logSys.error("No running Fail2Ban found")
|
|
sys.exit(-1)
|
|
|
|
# Process some options
|
|
for c in conf:
|
|
if c == "verbose":
|
|
logSys.warn("Verbose level is "+`conf[c]`)
|
|
if conf[c] == 1:
|
|
logSys.set_loglevel(log4py.LOGLEVEL_VERBOSE)
|
|
elif conf[c] > 1:
|
|
logSys.set_loglevel(log4py.LOGLEVEL_DEBUG)
|
|
elif c == "debug" and conf[c]:
|
|
logSys.set_loglevel(log4py.LOGLEVEL_DEBUG)
|
|
logSys.set_formatstring(log4py.FMT_DEBUG)
|
|
elif c == "background" and conf[c]:
|
|
retCode = createDaemon()
|
|
signal.signal(signal.SIGTERM, sigTERMhandler)
|
|
logSys.set_target(conf["logfile"])
|
|
if not retCode:
|
|
logSys.error("Unable to start daemon")
|
|
sys.exit(-1)
|
|
elif c == "logging" and conf[c]:
|
|
try:
|
|
open(conf["logfile"], "a")
|
|
logSys.set_target(conf["logfile"])
|
|
except IOError:
|
|
logSys.warn("Unable to log to "+conf["logfile"])
|
|
logSys.warn("Using default output for logging")
|
|
elif c == "ignoreip":
|
|
ignoreIPList = conf[c].split(' ')
|
|
elif c == "firewall":
|
|
conf[c] = string.lower(conf[c])
|
|
if conf[c] == "ipfw":
|
|
fireWallName = "Ipfw"
|
|
elif conf[c] == "ipfwadm":
|
|
fireWallName = "Ipfwadm"
|
|
else:
|
|
fireWallName = "Iptables"
|
|
|
|
# Checks for root user. This is necessary because log files
|
|
# are owned by root and firewall needs root access.
|
|
if not checkForRoot():
|
|
logSys.error("You must be root")
|
|
if not conf["debug"]:
|
|
sys.exit(-1)
|
|
|
|
# Checks that no instance of Fail2Ban is currently running.
|
|
pid = checkForPID(conf["pidlock"])
|
|
if pid:
|
|
logSys.error("Fail2Ban already running with PID "+pid)
|
|
sys.exit(-1)
|
|
else:
|
|
createPID(conf["pidlock"])
|
|
|
|
logSys.debug("ConfFile is "+conf["conffile"])
|
|
logSys.debug("BanTime is "+`conf["bantime"]`)
|
|
logSys.debug("retryAllowed is "+`conf["maxretry"]`)
|
|
|
|
# Reads the config file and create a LogReader instance for
|
|
# each log file to check.
|
|
confReader = ConfigReader(logSys, conf["conffile"]);
|
|
confReader.openConf()
|
|
logList = list()
|
|
for t in confReader.getSections():
|
|
l = confReader.getLogOptions(t)
|
|
if l["enabled"]:
|
|
lObj = LogReader(logSys, l["logfile"], l["timeregex"],
|
|
l["timepattern"], l["failregex"], conf["bantime"])
|
|
lObj.setName(t)
|
|
logList.append(lObj)
|
|
|
|
# Creates one instance of Iptables (thanks to Pyhton dynamic
|
|
# features).
|
|
fireWallObj = eval(fireWallName)
|
|
fireWall = fireWallObj(conf["bantime"], logSys, conf["interface"])
|
|
|
|
# IPFW needs rules number. The configuration option "ipfw-start-rule"
|
|
# defines the first rule number used by Fail2Ban.
|
|
if fireWallName == "Ipfw":
|
|
fireWall.setCrtRuleNbr(conf["ipfw-start-rule"])
|
|
|
|
# We add 127.0.0.1 to the ignore list has we do not want
|
|
# to be ban ourself.
|
|
for element in logList:
|
|
element.addIgnoreIP("127.0.0.1")
|
|
while len(ignoreIPList) > 0:
|
|
ip = ignoreIPList.pop()
|
|
for element in logList:
|
|
element.addIgnoreIP(ip)
|
|
|
|
logSys.info("Fail2Ban v"+version+" is running")
|
|
failListFull = dict()
|
|
# Main loop
|
|
while True:
|
|
try:
|
|
sys.stdout.flush()
|
|
sys.stderr.flush()
|
|
|
|
# Checks if some IP have to be remove from ban
|
|
# list.
|
|
fireWall.checkForUnBan(conf["debug"])
|
|
|
|
# If the log file has not been modified since the
|
|
# last time, we sleep for 1 second. This is active
|
|
# polling so not very effective.
|
|
modList = list()
|
|
for element in logList:
|
|
if element.isModified():
|
|
modList.append(element)
|
|
|
|
if len(modList) == 0:
|
|
time.sleep(conf["polltime"])
|
|
continue
|
|
|
|
# Gets the failure list from the log file. For a given IP,
|
|
# takes only the service which has the most password failures.
|
|
failList = dict()
|
|
for element in modList:
|
|
e = element.getFailures()
|
|
for key in e.iterkeys():
|
|
if failList.has_key(key):
|
|
if failList[key][0] < e[key][0]:
|
|
failList[key] = (e[key][0], e[key][1], element)
|
|
else:
|
|
failList[key] = (e[key][0], e[key][1], element)
|
|
|
|
# Add the last log failures to the global failure list.
|
|
for key in failList.iterkeys():
|
|
if failListFull.has_key(key):
|
|
failListFull[key] = (failListFull[key][0] + 1,
|
|
failList[key][1], failList[key][2])
|
|
else:
|
|
failListFull[key] = failList[key]
|
|
|
|
# Remove the oldest failure attempts from the global list.
|
|
unixTime = time.time()
|
|
failListFullTemp = failListFull.copy()
|
|
for key in failListFullTemp.iterkeys():
|
|
failTime = failListFullTemp[key][2].getFindTime()
|
|
if failListFullTemp[key][1] < unixTime - failTime:
|
|
del failListFull[key]
|
|
|
|
# We iterate the failure list and ban IP that make
|
|
# *retryAllowed* login failures.
|
|
failListFullTemp = failListFull.copy()
|
|
for key in failListFullTemp.iterkeys():
|
|
element = failListFullTemp[key]
|
|
if element[0] >= conf["maxretry"]:
|
|
logSys.info(element[2].getName()+": "+key+" has "+
|
|
`element[0]`+" login failure(s). Banned.")
|
|
fireWall.addBanIP(key, conf["debug"])
|
|
del failListFull[key]
|
|
|
|
except KeyboardInterrupt:
|
|
# When the user press <ctrl>+<c> we exit nicely.
|
|
killApp()
|