fail2ban/server/failregex.py

147 lines
3.9 KiB
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 re, sre_constants, logging
from template import Template
from timetemplate import TimeTemplates
from prefixtemplate import PrefixTemplates
from hosttemplate import HostTemplates
# Gets the instance of the logger.
logSys = logging.getLogger("fail2ban.filter.failregex")
class Regex:
def __init__(self, regex):
self.__originalRegex = regex
self.__convertedRegex = None
self.__compiledRegex = None
self.__templates = dict()
self.__hostRegex = None
self.__dateRegex = None
self.__prefixRegex = None
def process(self):
regex = self.__originalRegex
for item in self.__templates.values():
regex = regex.replace(item.getTag(), item.getRegex(), 1)
try:
self.__compiledRegex = re.compile(regex)
self.__convertedRegex = regex
except sre_constants.error:
raise RegexException("Unable to compile regular expression '%s'" %
regex)
def register(self, template):
self.__templates[template.getName()] = template
def getTemplate(self, tag):
return self.__templates[tag]
def match(self, line):
return self.__compiledRegex.match(line)
def getOriginalRegex(self):
return self.__originalRegex
def getConvertedRegex(self):
return self.__convertedRegex
class FailRegex:
HOST_TEMPLATES = HostTemplates()
PREFIX_TEMPLATES = PrefixTemplates()
TIME_TEMPLATES = TimeTemplates()
def __init__(self, regex):
self.__regex = Regex(regex)
self.__match = None
self.__found = False
def __autoDetection(self, line):
for host in self.HOST_TEMPLATES.getTemplates():
self.__regex.register(host)
for date in self.TIME_TEMPLATES.getTemplates():
self.__regex.register(date)
for prefix in self.PREFIX_TEMPLATES.getTemplates():
self.__regex.register(prefix)
self.__regex.process()
match = self.__regex.match(line)
if match:
self.__found = True
#logSys.debug("Auto-detection succeeded")
#logSys.debug("failregex is %s" %
# self.__regex.getConvertedRegex())
return match
return None
def search(self, line):
if self.__found:
self.__match = self.__regex.match(line)
else:
self.__match = self.__autoDetection(line)
def hasMatched(self):
if self.__match:
return True
else:
return False
def getOriginalRegex(self):
return self.__regex.getOriginalRegex()
def getHost(self):
template = self.__regex.getTemplate(Template.TEMPLATE_HOST)
host = self.__match.group(template.getName())
if host == None:
# Gets a few information.
s = self.__match.string
r = self.__match.re
raise RegexException("No 'host' found in '%s' using '%s'" % (s, r))
return host
def getTime(self):
template = self.__regex.getTemplate(Template.TEMPLATE_TIME)
time = self.__match.group(template.getName())
if time == None:
# Gets a few information.
s = self.__match.string
r = self.__match.re
raise RegexException("No 'time' found in '%s' using '%s'" % (s, r))
try:
return template.getTime(time)
except Exception:
return None
##
# Exception dedicated to the class Regex.
class RegexException(Exception):
pass