instructions

fail2ban-master/fail2ban/server/failmanager.py

@@ -0,0 +1,169 @@
+# emacs: -*- mode: python; py-indent-offset: 4; indent-tabs-mode: t -*-
+# vi: set ft=python sts=4 ts=4 sw=4 noet :
+
+# 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+# Author: Cyril Jaquier
+# 
+
+__author__ = "Cyril Jaquier"
+__copyright__ = "Copyright (c) 2004 Cyril Jaquier"
+__license__ = "GPL"
+
+from threading import Lock
+import logging
+
+from .ticket import FailTicket, BanTicket
+from ..helpers import getLogger, BgService
+
+# Gets the instance of the logger.
+logSys = getLogger(__name__)
+logLevel = logging.DEBUG
+
+
+class FailManager:
+	
+	def __init__(self):
+		self.__lock = Lock()
+		self.__failList = dict()
+		self.__maxRetry = 3
+		self.__maxTime = 600
+		self.__failTotal = 0
+		self.maxMatches = 5
+		self.__bgSvc = BgService()
+	
+	def setFailTotal(self, value):
+		self.__failTotal = value
+		
+	def getFailTotal(self):
+		return self.__failTotal
+	
+	def getFailCount(self):
+		# may be slow on large list of failures, should be used for test purposes only...
+		with self.__lock:
+			return len(self.__failList), sum([f.getRetry() for f in list(self.__failList.values())])
+
+	def setMaxRetry(self, value):
+		self.__maxRetry = value
+	
+	def getMaxRetry(self):
+		return self.__maxRetry
+	
+	def setMaxTime(self, value):
+		self.__maxTime = value
+	
+	def getMaxTime(self):
+		return self.__maxTime
+
+	def addFailure(self, ticket, count=1, observed=False):
+		attempts = 1
+		with self.__lock:
+			fid = ticket.getID()
+			try:
+				fData = self.__failList[fid]
+				# if the same object - the same matches but +1 attempt:
+				if fData is ticket:
+					matches = None
+					attempt = 1
+				else:
+					# will be incremented / extended (be sure we have at least +1 attempt):
+					matches = ticket.getMatches() if self.maxMatches else None
+					attempt = ticket.getAttempt()
+					if attempt <= 0:
+						attempt += 1
+				unixTime = ticket.getTime()
+				fData.adjustTime(unixTime, self.__maxTime)
+				fData.inc(matches, attempt, count)
+				# truncate to maxMatches:
+				if self.maxMatches:
+					matches = fData.getMatches()
+					if len(matches) > self.maxMatches:
+						fData.setMatches(matches[-self.maxMatches:])
+				else:
+					fData.setMatches(None)
+			except KeyError:
+				# not found - already banned - prevent to add failure if comes from observer:
+				if observed or isinstance(ticket, BanTicket):
+					return ticket.getRetry()
+				# if already FailTicket - add it direct, otherwise create (using copy all ticket data):
+				if isinstance(ticket, FailTicket):
+					fData = ticket;
+				else:
+					fData = FailTicket.wrap(ticket)
+				if count > ticket.getAttempt():
+					fData.setRetry(count)
+				self.__failList[fid] = fData
+
+			attempts = fData.getRetry()
+			self.__failTotal += 1
+
+			if logSys.getEffectiveLevel() <= logLevel:
+				# yoh: Since composing this list might be somewhat time consuming
+				# in case of having many active failures, it should be ran only
+				# if debug level is "low" enough
+				failures_summary = ', '.join(['%s:%d' % (k, v.getRetry())
+											  for k,v in  self.__failList.items()])
+				logSys.log(logLevel, "Total # of detected failures: %d. Current failures from %d IPs (IP:count): %s"
+							 % (self.__failTotal, len(self.__failList), failures_summary))
+
+		self.__bgSvc.service()
+		return attempts
+	
+	def size(self):
+		return len(self.__failList)
+	
+	def cleanup(self, time):
+		time -= self.__maxTime
+		with self.__lock:
+			todelete = [fid for fid,item in self.__failList.items() \
+				if item.getTime() <= time]
+			if len(todelete) == len(self.__failList):
+				# remove all:
+				self.__failList = dict()
+			elif not len(todelete):
+				# nothing:
+				return
+			if len(todelete) / 2.0 <= len(self.__failList) / 3.0:
+				# few as 2/3 should be removed - remove particular items:
+				for fid in todelete:
+					del self.__failList[fid]
+			else:
+				# create new dictionary without items to be deleted:
+				self.__failList = dict((fid,item) for fid,item in self.__failList.items() \
+					if item.getTime() > time)
+		self.__bgSvc.service()
+	
+	def delFailure(self, fid):
+		with self.__lock:
+			try:
+				del self.__failList[fid]
+			except KeyError:
+				pass
+	
+	def toBan(self, fid=None):
+		with self.__lock:
+			for fid in ([fid] if fid is not None and fid in self.__failList else self.__failList):
+				data = self.__failList[fid]
+				if data.getRetry() >= self.__maxRetry:
+					del self.__failList[fid]
+					return data
+		self.__bgSvc.service()
+		raise FailManagerEmpty
+
+
+class FailManagerEmpty(Exception):
+	pass