Bonjour à tous,
J’ai installé portsentry pour bloquer les scans sur mon serveur.
Il fonctionné hier matin puis maintenant plus rien, j’ai beau essayer des modifications sur le fichier principal rien y fait !
[code]nano /etc/portsentry/portsentry.conf
PortSentry Configuration
$Id: portsentry.conf.Debian,v 1.6 2001/07/19 21:02:20 agx Exp $
Original portsentry.conf by Craig H. Rowland crowland@psionic.com
modified for Debian by Guido Guenther agx@debian.org
IMPORTANT NOTE: You CAN NOT put spaces between your port arguments.
The default ports will catch a large number of common probes
All entries must be in quotes.
#######################
Port Configurations
#######################
Some example port configs for classic and basic Stealth modes
I like to always keep some ports at the “low” end of the spectrum.
This will detect a sequential port sweep really quickly and usually
these ports are not in use (i.e. tcpmux port 1)
** X-Windows Users **: If you are running X on your box, you need to be sure
you are not binding PortSentry to port 6000 (or port 2000 for OpenWindows users).
Doing so will prevent the X-client from starting properly.
These port bindings are ignored for Advanced Stealth Scan Detection Mode.
Un-comment these if you are really anal:
#TCP_PORTS=“1,7,9,11,15,70,79,80,109,110,111,119,138,139,143,512,513,514,515,540,635,1080,1524,2000,2001,4000,4001,5742,6000,6001,6667,12345,12346,20034,27665,30303,32771,32772,32773,32774,31337,40421,40425,49724,54320”
#UDP_PORTS=“1,7,9,66,67,68,69,111,137,138,161,162,474,513,517,518,635,640,641,666,700,2049,31335,27444,34555,32770,32771,32772,32773,32774,31337,54321”
Use these if you just want to be aware:
TCP_PORTS="1,11,15,79,111,119,143,540,635,1080,1524,2000,5742,6667,12345,12346,20034,27665,31337,32771,32772,32773,32774,40421,49724,54320"
UDP_PORTS=“1,7,9,69,161,162,513,635,640,641,700,37444,34555,31335,32770,32771,32772,32773,32774,31337,54321”
Use these for just bare-bones
#TCP_PORTS=“1,11,15,110,111,143,540,635,1080,1524,2000,12345,12346,20034,32771,32772,32773,32774,49724,54320”
#UDP_PORTS=“1,7,9,69,161,162,513,640,700,32770,32771,32772,32773,32774,31337,54321”
###########################################
Advanced Stealth Scan Detection Options
###########################################
This is the number of ports you want PortSentry to monitor in Advanced mode.
Any port below this number will be monitored. Right now it watches
everything below 1024.
On many Linux systems you cannot bind above port 61000. This is because
these ports are used as part of IP masquerading. I don’t recommend you
bind over this number of ports. Realistically: I DON’T RECOMMEND YOU MONITOR
OVER 1024 PORTS AS YOUR FALSE ALARM RATE WILL ALMOST CERTAINLY RISE. You’ve been
warned! Don’t write me if you have have a problem because I’ll only tell
you to RTFM and don’t run above the first 1024 ports.
ADVANCED_PORTS_TCP="1024"
ADVANCED_PORTS_UDP=“1024”
This field tells PortSentry what ports (besides listening daemons) to
ignore. This is helpful for services like ident that services such
as FTP, SMTP, and wrappers look for but you may not run (and probably
shouldn’t IMHO).
By specifying ports here PortSentry will simply not respond to
incoming requests, in effect PortSentry treats them as if they are
actual bound daemons. The default ports are ones reported as
problematic false alarms and should probably be left alone for
all but the most isolated systems/networks.
Default TCP ident and NetBIOS service
ADVANCED_EXCLUDE_TCP=“113,139”
Default UDP route (RIP), NetBIOS, bootp broadcasts.
ADVANCED_EXCLUDE_UDP=“520,138,137,67”
######################
Configuration Files#
######################
Hosts to ignore
IGNORE_FILE="/etc/portsentry/portsentry.ignore"
Hosts that have been denied (running history)
HISTORY_FILE="/var/lib/portsentry/portsentry.history"
Hosts that have been denied this session only (temporary until next restart)
BLOCKED_FILE="/var/lib/portsentry/portsentry.blocked"
##############################
Misc. Configuration Options#
##############################
DNS Name resolution - Setting this to “1” will turn on DNS lookups
for attacking hosts. Setting it to “0” (or any other value) will shut
it off.
RESOLVE_HOST = “0”
###################
Response Options#
###################
Options to dispose of attacker. Each is an action that will
be run if an attack is detected. If you don’t want a particular
option then comment it out and it will be skipped.
The variable $TARGET$ will be substituted with the target attacking
host when an attack is detected. The variable $PORT$ will be substituted
with the port that was scanned.
##################
Ignore Options
##################
These options allow you to enable automatic response
options for UDP/TCP. This is useful if you just want
warnings for connections, but don’t want to react for
a particular protocol (i.e. you want to block TCP, but
not UDP). To prevent a possible Denial of service attack
against UDP and stealth scan detection for TCP, you may
want to disable blocking, but leave the warning enabled.
I personally would wait for this to become a problem before
doing though as most attackers really aren’t doing this.
The third option allows you to run just the external command
in case of a scan to have a pager script or such execute
but not drop the route. This may be useful for some admins
who want to block TCP, but only want pager/e-mail warnings
on UDP, etc.
0 = Do not block UDP/TCP scans.
1 = Block UDP/TCP scans.
2 = Run external command only (KILL_RUN_CMD)
BLOCK_UDP="1"
BLOCK_TCP=“1”
###################
Dropping Routes:#
###################
This command is used to drop the route or add the host into
a local filter table.
The gateway (333.444.555.666) should ideally be a dead host on
the local subnet. On some hosts you can also point this at
localhost (127.0.0.1) and get the same effect. NOTE THAT
333.444.555.66 WILL NOT WORK. YOU NEED TO CHANGE IT!!
ALL KILL ROUTE OPTIONS ARE COMMENTED OUT INITIALLY. Make sure you
uncomment the correct line for your OS. If you OS is not listed
here and you have a route drop command that works then please
mail it to me so I can include it. ONLY ONE KILL_ROUTE OPTION
CAN BE USED AT A TIME SO DON’T UNCOMMENT MULTIPLE LINES.
NOTE: The route commands are the least optimal way of blocking
and do not provide complete protection against UDP attacks and
will still generate alarms for both UDP and stealth scans. I
always recommend you use a packet filter because they are made
for this purpose.
Generic
#KILL_ROUTE="/sbin/route add $TARGET$ 333.444.555.666"
Generic Linux
#KILL_ROUTE="/sbin/route add -host $TARGET$ gw 333.444.555.666"
Newer versions of Linux support the reject flag now. This
is cleaner than the above option.
KILL_ROUTE="/sbin/route add -host $TARGET$ reject"
Generic BSD (BSDI, OpenBSD, NetBSD, FreeBSD)
#KILL_ROUTE="/sbin/route add $TARGET$ 333.444.555.666"
Generic Sun
#KILL_ROUTE="/usr/sbin/route add $TARGET$ 333.444.555.666 1"
NEXTSTEP
#KILL_ROUTE="/usr/etc/route add $TARGET$ 127.0.0.1 1"
FreeBSD
#KILL_ROUTE=“route add -net $TARGET$ -netmask 255.255.255.255 127.0.0.1 -blackhole”
Digital UNIX 4.0D (OSF/1 / Compaq Tru64 UNIX)
#KILL_ROUTE="/sbin/route add -host -blackhole $TARGET$ 127.0.0.1"
Generic HP-UX
#KILL_ROUTE="/usr/sbin/route add net $TARGET$ netmask 255.255.255.0 127.0.0.1"
Using a packet filter is the PREFERRED. The below lines
work well on many OS’s. Remember, you can only uncomment one
KILL_ROUTE option.
ipfwadm support for Linux
#KILL_ROUTE="/sbin/ipfwadm -I -i deny -S $TARGET$ -o"
ipfwadm support for Linux (no logging of denied packets)
#KILL_ROUTE="/sbin/ipfwadm -I -i deny -S $TARGET$"
ipchain support for Linux
#KILL_ROUTE="/sbin/ipchains -I input -s $TARGET$ -j DENY -l"
ipchain support for Linux (no logging of denied packets)
#KILL_ROUTE="/sbin/ipchains -I input -s $TARGET$ -j DENY"
iptables support for Linux
#KILL_ROUTE="/sbin/iptables -I INPUT -s $TARGET$ -j DROP"
iptables support for Linux with limit and LOG support. Logs only
a limited number of packets to avoid a denial of service attack.
KILL_ROUTE="/sbin/iptables -I INPUT -s $TARGET$ -j DROP && /sbin/iptables -I INPUT -s $TARGET$ -m limit --limit 3/minute --limit-burst 5 -j LOG --log-level DEBUG --log-prefix 'Portsentry: dropping: '"
For those of you running FreeBSD (and compatible) you can
use their built in firewalling as well.
#KILL_ROUTE="/sbin/ipfw add 1 deny all from $TARGET$:255.255.255.255 to any"
For those running ipfilt (OpenBSD, etc.)
NOTE THAT YOU NEED TO CHANGE external_interface TO A VALID INTERFACE!!
#KILL_ROUTE="/bin/echo ‘block in log on external_interface from $TARGET$/32 to any’ | /sbin/ipf -f -"
###############
TCP Wrappers#
###############
This text will be dropped into the hosts.deny file for wrappers
to use. There are two formats for TCP wrappers:
Format One: Old Style - The default when extended host processing
options are not enabled.
#KILL_HOSTS_DENY=“ALL: $TARGET$”
Format Two: New Style - The format used when extended option
processing is enabled. You can drop in extended processing
options, but be sure you escape all ‘%’ symbols with a backslash
to prevent problems writing out (i.e. %c %h )
KILL_HOSTS_DENY=“ALL: $TARGET$ : DENY”
###################
External Command#
###################
This is a command that is run when a host connects, it can be whatever
you want it to be (pager, etc.). This command is executed before the
route is dropped or after depending on the KILL_RUN_CMD_FIRST option below
I NEVER RECOMMEND YOU PUT IN RETALIATORY ACTIONS AGAINST THE HOST SCANNING
YOU!
TCP/IP is an unauthenticated protocol and people can make scans appear out
of thin air. The only time it is reasonably safe (and I never think it is
reasonable) to run reverse probe scripts is when using the “classic” -tcp mode.
This mode requires a full connect and is very hard to spoof.
The KILL_RUN_CMD_FIRST value should be set to “1” to force the command
to run before the blocking occurs and should be set to “0” to make the
command run after the blocking has occurred.
#KILL_RUN_CMD_FIRST = “0”
#KILL_RUN_CMD="/some/path/here/script $TARGET$ $PORT$ $MODE$"
for examples see /usr/share/doc/portsentry/examples/
KILL_RUN_CMD = “/sbin/iptables -I INPUT -s $TARGET$ -j DROP && echo ‘Tentative de Scan par $TARGET$’ | mail -s ‘Tentative de Scan’ XXXXX@gmail.com”
#####################
Scan trigger value#
#####################
Enter in the number of port connects you will allow before an
alarm is given. The default is 0 which will react immediately.
A value of 1 or 2 will reduce false alarms. Anything higher is
probably not necessary. This value must always be specified, but
generally can be left at 0.
NOTE: If you are using the advanced detection option you need to
be careful that you don’t make a hair trigger situation. Because
Advanced mode will react for any host connecting to a non-used
port below your specified range, you have the opportunity to
really break things. (i.e someone innocently tries to connect to
you via SSL [TCP port 443] and you immediately block them). Some
of you may even want this though. Just be careful.
SCAN_TRIGGER=“0”
######################
Port Banner Section#
######################
Enter text in here you want displayed to a person tripping the PortSentry.
I don’t recommend taunting the person as this will aggravate them.
Leave this commented out to disable the feature
Stealth scan detection modes don’t use this feature
#PORT_BANNER="** UNAUTHORIZED ACCESS PROHIBITED *** YOUR CONNECTION ATTEMPT HAS BEEN LOGGED. GO AWAY."
EOF[/code]
[code]nano /etc/default/portsentry
/etc/default/portsentry
This file is read by /etc/init.d/portsentry. See the portsentry.8
manpage for details.
The options in this file refer to commandline arguments (all in lowercase)
of portsentry. Use only one tcp and udp mode at a time.
TCP_MODE="atcp"
UDP_MODE=“audp”[/code]
[code]cat /etc/portsentry/portsentry.ignore
/etc/portsentry/portsentry.ignore: Contains all IPs portsentry(8)
will never block.
This file was generated by /usr/lib/portsentry/portsentry-build-ignore-file.
DO NOT EDIT - edit /etc/portsentry/portsentry.ignore.static instead and use
“/etc/init.d/portsentry restart” to reload the configuration.
IPs from /etc/portsentry/portsentry.ignore.static:
127.0.0.1/32
0.0.0.0
66.249.64.0/19
109.XXX.XXX.XXX # Mon IP Publique
dynamically fetched IPs(via ifconfig -a):
91.XXX.XXX.XXX # IP de mon serveur
127.0.0.1[/code]
J’ai bien entendu redémarré portsentry après modification et pour le coup, je ne vois pas d’où vient le problème.
Qu’en pensez-vous ?
J’ai fait des tests hier soir et ce matin via des outils en ligne avec nmap et aucune IP bloqué.
Si vous voulez faire un test directement de chez vous avec nmap, je vous enverrai mon IP en MP.
Merci beaucoup