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problemas con fail2ban, no banea nada [SOLUCIONADO]

Publicado: 1 Febrero, 2008 - 21:14 problemas con fail2ban, no banea nada [SOLUCIONADO]

Hola gente, me siento un inutil, pero despues de un rato largo no puedo hacer andar el fail2ban; no banea ninguna ip...Uso debian 4.0r1 y fail2ban 0.7.5-2, A continuacion mando mis archivos de configuracion:
/etc/fail2ban/jail.conf

# Fail2Ban configuration file.
#
# This file was composed for Debian systems from the original one
#  provided now under /usr/share/doc/fail2ban/examples/jail.conf
#  for additional examples.
#
# To avoid merges during upgrades DO NOT MODIFY THIS FILE
# and rather provide your changes in /etc/fail2ban/jail.local
#
# Author: Yaroslav O. Halchenko <debian@onerussian.com>
#
# $Revision: 281 $
#

# The DEFAULT allows a global definition of the options. They can be override
# in each jail afterwards.

[DEFAULT]

# "ignoreip" can be an IP address, a CIDR mask or a DNS host
ignoreip = 127.0.0.1
bantime  = 600
maxretry = 3

# "backend" specifies the backend used to get files modification. Available
# options are "gamin", "polling" and "auto".
# yoh: For some reason Debian shipped python-gamin didn't work as expected
#      This issue left ToDo, so polling is default backend for now
backend = polling

#
# Destination email address used solely for the interpolations in
# jail.{conf,local} configuration files.
destemail = root@localhost

# Default action to take: ban only
action = iptables[name=%(__name__)s, port=%(port)s]

# Following actions can be chosen as an alternatives to the above action.
# To activate, just copy/paste+uncomment chosen 2 (excluding comments) lines
# into jail.local

# Default action to take: ban & send an e-mail with whois report
# to the destemail.
# action = iptables[name=%(__name__)s, port=%(port)s]
#          mail-whois[name=%(__name__)s, dest=%(destemail)s]

# Default action to take: ban & send an e-mail with whois report
# and relevant log lines to the destemail.
# action = iptables[name=%(__name__)s, port=%(port)s]
#          mail-whois-lines[name=%(__name__)s, dest=%(destemail)s, logpath=%(logpath)s]

# Next jails corresponds to the standard configuration in Fail2ban 0.6
# which was shipped in Debian. Please enable any defined here jail by including
#
# [SECTION_NAME]
# enabled = true
#
# in /etc/fail2ban/jail.local.
#

[ssh]

enabled = true
filter  = sshd
action   = iptables[name=ssh,port=222,protocol=tcp]
logpath  = /var/log/auth.log
maxretry = 3
bantime = 600

#
# HTTP servers
#

[apache]

enabled = false
port    = http
filter  = apache-auth
logpath = /var/log/apache*/*access.log
maxretry = 6


[apache-noscript]

enabled = false
port    = http
filter  = apache-noscript
logpath = /var/log/apache*/*error.log
maxretry = 6

#
# FTP servers
#

[vsftpd]

enabled  = false
port     = ftp
filter   = vsftpd
logpath  = /var/log/auth.log
maxretry = 6


[proftpd]

enabled  = false
port     = ftp
filter   = proftpd
logpath  = /var/log/proftpd/proftpd.log
maxretry = 6


[wuftpd]

enabled  = false
port     = ftp
filter   = wuftpd
logpath  = /var/log/auth.log
maxretry = 6


#
# Mail servers
#

[postfix]

enabled  = false
port     = smtp
filter   = postfix
logpath  = /var/log/postfix.log


[couriersmtp]

enabled  = false
port     = smtp
filter   = couriersmtp
logpath  = /var/log/mail.log


[sasl]

enabled  = false
port     = smtp
filter   = sasl
logpath  = /var/log/mail.log

/etc/fail2ban/fail2ban.conf

# Fail2Ban configuration file
#
# Author: Cyril Jaquier
#
# $Revision: 412 $
#

[Definition]

# Option:  loglevel
# Notes.:  Set the log level output.
#          1 = ERROR
#          2 = WARN
#          3 = INFO
#          4 = DEBUG
# Values:  NUM  Default:  3
#
loglevel = 3

# Option:  logtarget
# Notes.:  Set the log target. This could be a file, SYSLOG, STDERR.
# Values:  STDERR SYSLOG file  Default:  /var/log/fail2ban.log
#
logtarget = /var/log/fail2ban.log

# Option: socket
# Notes.: Set the socket file. This is used to communication with the
#         daemon.
# Values: FILE  Default:  /tmp/fail2ban.sock
#
socket = /tmp/fail2ban.sock

Escucho sugerencias...

Mil gracias.

Tiodary

Publicado: 1 Febrero, 2008 - 21:51 Re: problemas con fail2ban, no banea nada [SOLUCIONADO] #1

Mira, te pongo mi archivo /etc/fail2ban/jail.conf. Este si que funciona, ya que es el que tengo puesto en uno de los servidores Debian y los he comprobado (De hecho me llegan los emails avisándome y demás).

[DEFAULT]

# "ignoreip" can be an IP address, a CIDR mask or a DNS host
ignoreip = 127.0.0.1 192.168.1.6
bantime  = 36000
maxretry = 3

# "backend" specifies the backend used to get files modification. Available
# options are "gamin", "polling" and "auto".
# yoh: For some reason Debian shipped python-gamin didn't work as expected
#      This issue left ToDo, so polling is default backend for now
backend = polling

#
# Destination email address used solely for the interpolations in
# jail.{conf,local} configuration files.
destemail = miemail@midominio.com

# Default action to take: ban only
action = iptables[name=%(__name__)s, port=%(port)s]
	 mail-whois-lines[name=%(__name__)s, dest=%(destemail)s, logpath=%(logpath)s]


[ssh]

enabled = true
port    = ssh
filter  = sshd
logpath  = /var/log/auth.log
maxretry = 5


[apache]

enabled = true
port    = http
filter  = apache-auth
logpath = /var/log/apache*/*error.log
maxretry = 5


[apache-noscript]

enabled = false
port    = http
filter  = apache-noscript
logpath = /var/log/apache*/*error.log
maxretry = 5


[vsftpd]

enabled  = false
port     = ftp
filter   = vsftpd
logpath  = /var/log/auth.log
maxretry = 5


[proftpd]

enabled  = true
port     = ftp
filter   = proftpd
logpath  = /var/log/auth.log
failregex = proftpd: \(pam_unix\) authentication failure; .* rhost=<HOST>
maxretry = 5


[wuftpd]

enabled  = false
port     = ftp
filter   = wuftpd
logpath  = /var/log/auth.log
maxretry = 5


[postfix]

enabled  = true
port     = smtp
filter   = postfix
logpath  = /var/log/mail.log
maxretry = 5


[courierpop3]

enabled  = true
port     = pop3
filter   = courierlogin
failregex = courierpop3login: LOGIN FAILED.*ip=\[.*:<HOST>\]
logpath  = /var/log/mail.log
maxretry = 5


[courierimap]

enabled  = true
port     = imap2
filter   = courierlogin
failregex = imapd: LOGIN FAILED.*ip=\[.*:<HOST>\]
logpath  = /var/log/mail.log
maxretry = 5


[sasl]

enabled  = true
port     = smtp
filter   = sasl
failregex = warning: [-._\w]+\[<HOST>\]: SASL (?:LOGIN|PLAIN|(?:CRAM|DIGEST)-MD5) authentication failed
logpath  = /var/log/mail.log
maxretry = 5

En cuanto al archivo /etc/fail2ban/fail2ban.conf,lo tengo exactamente igual que el tuyo.

Un saludo.

Publicado: 4 Febrero, 2008 - 16:45 Re: problemas con fail2ban, no banea nada [SOLUCIONADO] #2

gracias lyman creo que el problema esta en /etc/fail2ban/filter.d/sshd.conf en donde esta la linea que detectaria los ataques, si la pruebo con fail2ban-regex nunca me devuelve ninguna coincidencia....el archivo contiene lo siguiente:

# Fail2Ban configuration file
#
# Author: Cyril Jaquier
#
# $Revision: 471 $
#

[Definition]

# Option:  failregex
# Notes.:  regex to match the password failures messages in the logfile. The
#          host must be matched by a group named "host". The tag "<HOST>" can
#          be used for standard IP/hostname matching.
# Values:  TEXT
#
failregex = (?:(?:Authentication failure|Failed [-/\w+]+) for(?: [iI](?:llegal|n                                              valid) user)?|[Ii](?:llegal|nvalid) user|ROOT LOGIN REFUSED) .*(?: from|FROM) <H                                              OST>(?: port \d*)?(?: ssh\d*)?\s*$

#failregex = (?:Authentication failure|Failed [-/\w+]+) for .*(?: from|FROM) <HO                                              ST>

# Option:  ignoreregex
# Notes.:  regex to ignore. If this regex matches, the line is ignored.
# Values:  TEXT
#
ignoreregex =
parmapena:/etc/fail2ban/filter.d# cat sshd.conf
# Fail2Ban configuration file
#
# Author: Cyril Jaquier
#
# $Revision: 471 $
#

[Definition]

# Option:  failregex
# Notes.:  regex to match the password failures messages in the logfile. The
#          host must be matched by a group named "host". The tag "<HOST>" can
#          be used for standard IP/hostname matching.
# Values:  TEXT
#
failregex = (?:(?:Authentication failure|Failed [-/\w+]+) for(?: [iI](?:llegal|nvalid) user)?|[Ii](?:llegal|nvalid) user|ROOT LOGIN REFUSED) .*(?: from|FROM) <HOST>(?: port \d*)?(?: ssh\d*)?\s*$

#failregex = (?:Authentication failure|Failed [-/\w+]+) for .*(?: from|FROM) <HOST>

# Option:  ignoreregex
# Notes.:  regex to ignore. If this regex matches, the line is ignored.
# Values:  TEXT
#

Gracias nuevamente.

Salutti
tiodary

Publicado: 4 Febrero, 2008 - 19:10 Re: problemas con fail2ban, no banea nada [SOLUCIONADO] #3

Pasos que yo seguiría:
1) dpkg-reconfigure fail2ban, y lo dejaría tal y como viene por defecto.
2) Crear /etc/fail2ban/jail.local (copiar el jail.conf) y efectuar ahí las modificaciones posteriores
3) Si se usa un puerto que no es el que viene por defecto, indicarlo así:
[ssh]
enabled = true
port = 222
filter = sshd
logpath = /var/log/auth.log
maxretry = 3
4) Si aún así no te funciona, este es el failregex de sshd en una máquina que está funcionando:

failregex = (?:error: PAM: )?Authentication failure for .* from <HOST>s*$
            Failed [-/w]+ for .* from <HOST>(?: port d*)?(?: sshd*)?s*$
            ROOT LOGIN REFUSED.* FROM <HOST>s*$
            [iI](?:llegal|nvalid) user .* from <HOST>s*$
            User .+ from <HOST> not allowed because not listed in AllowUserss*$
            User .+ from <HOST> not allowed because none of user's groups are listed in AllowGroupss*$

Suerte!

Publicado: 5 Febrero, 2008 - 15:01 Re: problemas con fail2ban, no banea nada [SOLUCIONADO] #4

gracias a todos! lo solucione instalando la version 0.8.1-3 desde los backports....

salutti
tiodary