IRC Defender - http://ircdefender.sourceforge.net/
Developed for irc.chatspike.net and the irc community
Lead Developer: Brain
Contributors: WhiteWolf, openglx, reed and others
Module Developers: ol, typobox43, Azhrarn
Website Design: Craig
If you like this software, please drop us an email at
[email protected] so that we can get a rough idea of
how many users are using this program :-)
Supported software
To use this program, your irc software must be listed in the table
below. Support for other styles of ircd may be added on request however
we may ask you for assistance in providing access to the said software
so that we may develop a solution.
+-------------------------------------+-------------+
| irc server | Link module |
+-------------------------------------+-------------+
| UnrealIRCd 3.1.1 -> 3.2 | unreal |
| Bahamut 1.8.x | bahamut |
| UltimateIRCd 3.x | ultimate |
| Bahamut 1.4.x (unstable) | ultimate |
| Hybrid 7.x | hybrid |
| P10 (IRCu, beware ircd, etc.) | p10 |
| UnrealIRCd client mode (deprecated) | client |
| TR-IRCD | trircd |
| ptlink | ptlink6 |
| ircd 2.10 (RFC 2813) | ircd210 |
| InspIRCd Beta 6 to 1.0.7 | inspircd10 |
| InspIRCd 1.1.0 Beta 2 onwards | inspircd11 |
+-------------------------------------+-------------+
Thanks to WhiteWolf for submitting the TR-IRCD module used in ircdefender,
and thanks to openglx for his ptlink6 module, both of which are available
for your use due to their hard work and support of this project.
Also a Big thanks to laXity of irc.bongster.de for his support and access
to an UltimateIRCd test server which was used to develop the
bahamut/ultimate support module, and a big thanks also to beware who
and reed who gave advice and code for the P10 link protocol (also
thanks for writing such an easy-to-follow spec for what is a complex
protocol!).
Shared Blocks And U:Lines
If you link to an InspIRCd server, you must define a tag for
your defender server, for example:
If you link to a hybrid server, you will most likely need to create a
shared {} block (equivalent to a U-line), for your server, for example:
shared { name = "defender.mynetwork.net"; };
This will allow the defender server to set global k-lines (which will
be used whenever defender wishes to ban a host) Be sure to disable
command rate limiting for the defender server, or the "status" command
(see below) will be practically useless! Adding a can_flood in the auth
{} block or increasing the limits should have the desired effect.
If you link to a p10-compatible server such as ircu, you must add
u:lines to all your servers, for example:
U:defender.mynetwork.com:Defender:*
This will serve two purposes, firstly it allows your defender to
perform modehacks (e.g. for the flood module etc) and global kills, and
secondly it doubles as a Q:line, forbidding normal users from using the
nick 'Defender'.
On an ircd2.10 server, glines and globops are emulated by irc defender,
and restarts of the service will reset all emulated glines.
The server numeric
------------------
Certain server types feature what is known as a 'server numeric'. These
are normally allocated to you by the network administration of the
network you link your server to. Depending on the module you select you
will have to define a line in your conf as follows:
numeric=
At present, only three of the four modules in this distribution make use
of numerics, and the formats are as follows:
+-------------------+---------------------------------+---------------+
| module type | numeric format | example |
+-------------------+---------------------------------+---------------+
| unreal | integer number, 1..255 | 156 |
| p10 | two alphanumeric characters | QZ B5 f4 hE |
| trircd | integer number, 1..255 | 28 |
+-------------------+---------------------------------+---------------+
Starting the program
--------------------
See the example config file for details of configuration.
Start the program with "perl defender.pl"
The program will background, and auto join the channel you have defined
where the commands given below are accepted. Please be sure to secure
your channel (e.g. set +O on it) so that normal users may not access
these commands!
Deciding what modules to use
----------------------------
The program is modular, therefore you must select the modules you wish
to use before proceeding with running the program. There are two
special types of module, protocol and log modules, which are special in
the regard that you must ALWAYS have at least one of each loaded and
running. The protocol module provides the interface to the irc network
and the logging module provides the interface to writing logs by
redirecting stdout to handlers or files.
Once you have defined these two files in your config you are able to
pick other modules, see the config for an example. These modules
perform the actual scanning operations on users as they connect or
interact with the service.
Rehashing/Changing modules on the fly
-------------------------------------
While the program is running, you may edit its config file then do a
remote rehash (e.g. via /rehash defender.*) to cause its configuration
files to be re-read. When you do this any modules you have removed from
the configuration will be unloaded, and any you have added will be
freshly loaded. Any that remain unchanged will be re-initialised as
though the bot was just reloaded by hand. It your server software does
not support remote rehashing, then you may do this instead on the bot's
control channel:
botnick rehash
which will have the same effect as a /rehash on servers which support it.
Load order
----------
As with most modular programs, the load order of your modules is
important. Each module in defender has a set of dependencies, and a set
of features it provides, so that modules can safely depend on each
other in a stable and reliable way. It is up to you to ensure your
modules are loaded in the right order not to cause conflicts and are
not loaded multiple times. For example, if module A depends on module
B, you must ensure that B appears before A in your modules= line in the
config. Modules are loaded in order entered into the config file, from
left to right.
Listing loaded modules
----------------------
To list all loaded modules, and show the program uptime, simply type:
status
on it's control channel.
If you wish for (very) verbose output you may type:
status all
if you want the program to report verbose information for one module
only you may do this by typing:
status [module-name]
where module-name is the name of a module which is loaded.
Included modules
================
The following modules are included in the base distribution:
fyle
----
This module scans for anatoly/fyle drones, e.g. bots with nicks such as
`|{{] which join and part large channels in search of people to spam
infection urls to. It will ban them by heuristics, giving virus like
gecos, nick and ident combinations a heavier weighting. The paranoia=
score in the config indicates how sensitive this should be, you are
STRONGLY recommended to leave it at the default of 7.
Supported commands: fyle scan [nick] [ident] [gecos]
Note that to make this module work you will require the words.txt file
from the project page at http://www.sourceforge.net/projects/ircdefender/
killchan
--------
The killchan module will deny users access to specified channels. To use
the killchan module, use the following commands on the control channel:
killchan add [channel] [reason]
killchan list
killchan del [channel]
When a non-oper joins a blacklisted channel, they will be temporarily
G-Lined (the default is for 30 minutes). If an oper joins the forbidden
channel they will just be warned that the channel is blacklisted, so they
dont accidentally tell any non-opers to join.
TIP: It is a GOOD idea to put a killchan on your defender control channel,
if your ircd only supports the most basic of channel security features
such as +i, +s and +k. This way, if a normal user splitrides into the
control channel, gets invited by an oper by accident (or on purpose!)
or obtains the key, the killchan setting will G-Line them as soon as
they join, while still letting opers gain access to the pseudoclient.
This will also protect the channel whenever defender is running even
if for example services, GNUWorld or whatever enforces the channel
security on your control channel is unavailable due to DoS or netsplit,
so that while ever there is a pseudoclient to issue commands to, it
will ALWAYS be inaccessible to non-opers.
message
-------
This simple module replies with a server notice if the bot is messaged,
asking users to refer to your support channel for help.
fizzer
------
This module eliminates fizzer drones. It has no configuration options
or commands.
re_notice
---------
This module allows you to send a notice to all users on your network
which match a given regular expression pattern. For example, you could
send a message to all AOL users, or to all users in finland, or to all
users with broken idents (or even all users whose ident contains a
number, the possibilities are huge!) The module supports one command:
re_notice [regexp] [message]
The regexp is not automatically anchored, so where required remember to
use ^ and $ to anchor your regexp. (if you are unsure on the syntax of
regular expressions, google is as good source of help as anything).
nickflood
---------
This module detects nickfloods. You must add a value to your config
file as follows:
nickflood_limit=5
This will /KILL all users who exceed 5 nickchanges in 5 seconds. When a
user is killed, a message is put onto the control channel to announce it.
flood
-----
This module prevents large-scale botnet flooding of channels on your
network. It provides a layer of protection which a channel cannot
disable accidentally or otherwise (however they can override any locks
by setting chanserv modelocks). The module has three thresholds and an
interval, which can be set in the config file as follows:
flood_log=5
flood_globops=10
flood_lock=15
flood_interval=5
The first value is how many joins and parts constitute logging to the
channel. If a channel has this many joins and parts, it will be logged
on the channel you designated as Defender's "home" channel, e.g.:
Channel #test has had 6 joins/parts in the past 5 seconds,
10 triggers oper alert.
The second value, if exceeded, causes the service to put out a GLOBOPS
similar to above except sent to all opers.
If the third value is exceeded, the channel is locked down with the
modes +miCKc to prevent further flooding, and the lock is automatically
undone after a minute.
The fourth value is the 'interval', e.g. how long to let the counters
build up for. For example if you set this to 5, all the counters will
be X joins/5 secs.
secureoper
----------
This module watches for oper-ups. It can only be run when your defender
is running using a server protocol and not when your defender is
operating as an opered client. It will also require you to U:Line the
server on your network so that it can deoper clients. You must define a
list of regexp nicknames in the file opernicks.conf (in the config
directory), seperated by newlines. For example, [Brain] (remember to
escape characters such as [ and !) Any users that oper up who's nicks
do not match nicks in the config file will be de-opered by the service,
providing a second level of security against:
o Users who try to add o:lines for themselves for example during
trial links
o Admins who may try and add local oper status for their friends
o Containment of compromised boxes where o:lines are added by
intruders
etc etc...
You might think that these situations can be limited if your selection
process is strict enough, but why take the risk? :-)
cgiirc
------
This module blocks cgi:irc users from accessing your network without
accessing it from an authorised site.
As of version 1.4.0 this module maintains a list of authorised CGI:IRC
sites, each of which is a regexp which matches the sites hostname.
Edit the config file cgiirc.conf, and place into the config file a list
of regexps (one per line) which match the hostnames which are allowed to
use CGI:IRC.
As of v1.3.6, this module will set a timed G-line (ten minutes) when it
detects a cgi:irc client, to prevent hammering of the server and
spamming of the control channel.
regexp_akill
------------
This module allows you to set regexp based akills on users based on
nick, ident, host and gecos. Please see the comments in the module file
for examples.
Supported commands: regexp_akill add [hostmask] [reason]
regexp_akill del [hostmask]
regexp_akill list
As of v1.3.6, this module will set a timed G-line (ten minutes) when it
matches a banned nick, host or GECOS to prevent hammering of the server
and spamming of the control channel.
version
-------
This module serves two purposes. Firstly it can maintain a version
blacklist to stop blacklisted client versions from connecting to your
network. You should create a tab-separated file in your data dir,
formatted as follows:
regexp G ban-reason
regexp2 G ban-reason2
regexp3 W warning-1
The first field is a regexp. If the regexp matches the version of a
connecting client (e.g. "mirc.+6..+") then an action will be taken.
The action to be taken is represented by the second field, which can
be a G or a W. placing a G in this field makes the module G-line the
user, the third parameter being placed into the ban reason. Placing a
W in this field makes the module warn the user via privmsg, notifying
them so that they may fix the problem. In this case the text given in
the third field is sent to the user as-is.
Example config:
---------------
Bottler.+ G XDCC Looker bots are not allowed here!
mIRC.+5.+Bey W You are running an insecure mirc version, please upgrade
mIRC.+3.+ W Why are you running a 10 year old copy of mirc?
eggdrop.+ G NO BOTS!
x-chats2.0.5 W Insecure x-chat version, please upgrade asap
This module also supports simple surveying of client verisons, so that
you can for example determine what number of users are using mIRC, or
x-chat, or irssi.
As of v1.3.6, this module will set a timed G-line (ten minutes) when it
detects a banned version response, to prevent hammering of the server
and spamming of the control channel.
conn_average
------------
This module will monitor the connections per minute on all your servers
and fire off an alert via GLOBOPS if the limit increases past an
administrator defined level. You must add a line such as the following
to your defender.conf:
conn_average_max=100
This indicates that if the connections per minute over the entire
network increases past 100, the notice should be sent out.
spammage
--------
The spammage module is new to 1.4.x, and will detect repeated lines in
a channel, wether or not these lines actually come from seperate clients,
or the same client. Once triggered, all clients which repeat this line will
be G-lined for ten minutes.
Because this is relatively resource intensive, a channel must be monitored
explicitly by issuing the 'monitor' command on the control channel. The valid
commands are as follows:
spammage monitor [#channel] [threshold] [reason]
spammage unmonitor [#channel]
When a channel is being monitored, a line must be repeated [threshold] times
before the protection is activated. Once the protection is activated, users
sending the line as privmsg or notice will be glined with the given reason.
Any user who types any other line resets the spam counter to zero. Note that
this makes this module particularly effective against certain types of
spambots, but weak against others. Use this module where you think it would
have a noticable effect (e.g. where all the bots repeat the same phrase).
+---------------------------------------------+
| Parts of this software based on PotBot |
| (a simple perl bot: http://potbot.lv6.net/) |
+---------------------------------------------+
Contact:
You may contact the authors of this software at #Defender on
irc.chatspike.net, or by the sourceforge project page at
http://ircdefender.sourceforge.net/
-------------------------------------------------------------------------------
GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software Foundation, Inc.
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
Preamble
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GNU GENERAL PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. This License applies to any program or other work which contains
a notice placed by the copyright holder saying it may be distributed
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NO WARRANTY
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END OF TERMS AND CONDITIONS
How to Apply These Terms to Your New Programs
If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.
To do so, attach the following notices to the program. It is safest
to attach them to the start of each source file to most effectively
convey the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.
Copyright (C)
This program 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.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Also add information on how to contact you by electronic and paper mail.
If the program is interactive, make it output a short notice like this
when it starts in an interactive mode:
Gnomovision version 69, Copyright (C) year name of author
Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
This is free software, and you are welcome to redistribute it
under certain conditions; type `show c' for details.
The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License. Of course, the commands you use may
be called something other than `show w' and `show c'; they could even be
mouse-clicks or menu items--whatever suits your program.
You should also get your employer (if you work as a programmer) or your
school, if any, to sign a "copyright disclaimer" for the program, if
necessary. Here is a sample; alter the names:
Yoyodyne, Inc., hereby disclaims all copyright interest in the program
`Gnomovision' (which makes passes at compilers) written by James Hacker.
, 1 April 1989
Ty Coon, President of Vice
This General Public License does not permit incorporating your program into
proprietary programs. If your program is a subroutine library, you may
consider it more useful to permit linking proprietary applications with the
library. If this is what you want to do, use the GNU Library General
Public License instead of this License.