NAME¶
config_ndpmon.xml - Configuration file for ndpmon
DESCRIPTION¶
This manual page documents briefly the various options for configuring ndpmon.
NDPMon uses two configuration files, whose locations are:
/etc/ndpmon/config_ndpmon.xml
/var/lib/ndpmon/neighbor_list.xml
DTDs have been written for these two files:
config_ndpmon.dtd
neighbor_list.dtd
The Neighbor List is filled by the program itself, while running or during a
learning period. The configuration file itself has to be filled in by the
administrator.
Basic configuration example
Here is an example of a configuration file for NDPMON:
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE config_ndpmon SYSTEM "/etc/ndpmon/config_ndpmon.dtd">
<config_ndpmon>
<ignor_autoconf>1</ignor_autoconf>
<syslog_facility>LOG_LOCAL1</syslog_facility>
<admin_mail>frederic.beck@loria.fr</admin_mail>
<actions_low_pri>
<sendmail>1</sendmail>
<syslog>1</syslog>
<exec_pipe_program>/usr/lib/ndpmon/demopipeprogram.pl</exec_pipe_program>
</actions_low_pri>
<actions_high_pri>
<sendmail>1</sendmail>
<syslog>1</syslog>
<exec_pipe_program>/usr/lib/ndpmon/demopipeprogram.pl</exec_pipe_program>
</actions_high_pri>
<use_reverse_hostlookups>1</use_reverse_hostlookups>
<routers>
<router>
<mac>00:13:72:14:C4:58</mac>
<lla>fe80:213:72ff:fe14:c458</lla>
<prefixes>
<prefix>
<address>2001:660:4501:32:</address>
<mask>64</mask>
</prefix>
</prefixes>
<addresses>
<address>2001:660:4501:32::1</address>
</addresses>
</router>
</routers>
</config_ndpmon>
ignor_autoconf
/proc/sys/net/ipv6/conf/all/autoconf
/proc/sys/net/ipv6/conf/all/accept_ra
/proc/sys/net/ipv6/conf/all/accept_ra_defrtr
/proc/sys/net/ipv6/conf/all/ra_pinfo
/proc/sys/net/ipv6/conf/all/accept-ra_redirects
By setting this parameter to 0, the host will ignore all Router Advertisements
or ICMPv6 Redirects, and will thus not be sensitive to attacks on these
messages, but should still be able to send the alerts to the monitoring
station. Caution: the administrator must be aware that this will disable the
possibility for the host to use IPv6 Address Autoconfiguration, which could
cause trouble in case of a renumbering or a modification in the network's
topology.
syslog_facility
This parameter sets the facility Syslog will use for logging. To redirect
messages to a dedicated log file, reconfigure the syslog daemon itself.
admin_mail
The email address to which the ndpmon daemon will send alerts. The default is
set to root@localhost.
actions_low_pri/actions_high_pri
Enable or disable the alerts
sendmail: send an email to the administrator email address
syslog: syslog the message
exec_pipe_program: the program to call to capture the reports and do
whatever you want with it (see demopipeprogram.pl
in the source code)
routers
A router is defined with its MAC and Link Local addresses. It also contains the
list of prefixes advertised by this router, and eventually the global
addresses set on its interfaces. This new definition makes possible to check
the tuple (MAC, LLA, PREFIX) in the received Router Advertisements, instead of
checking them separately in version 0.1.
In version 1.4.0, additional tags were introduced to check the parameters of a
Router Advertisement. For details see below.
Configuring the Router Advertisement parameter check
In version 1.4.0, further checks for Router Advertisements (RAs) were introduced
which assume that the RA parameters do not change during operation. Those
values may be learned during the learning phase of NDPMon or they may be
configured manually. This behavior is optional. If you do not include the
additional parameters, no checks will be performed.
Below you will find an example of a more complex router definition:
<router>
<mac>00:11:22:33:44:55</mac>
<lla>fe80:0:0:0:211:22ff:fe33:4455</lla>
<param_curhoplimit>64</param_curhoplimit>
<param_flags_reserved>0</param_flags_reserved>
<param_router_lifetime>10800</param_router_lifetime>
<param_reachable_timer>0</param_reachable_timer>
<param_retrans_timer>0</param)retrans_timer>
<param_mtu>0</param_mtu>
<params_volatile>0</params_volatile>
<prefixes>
<prefix>
<address>2001:db8:1234:5678:0:0:0:0</address>
<mask>64</mask>
<param_flags_reserved>224</param_flags_reserved>
<param_valid_time>2592000</param_valid_time>
<param_preferred_time>604800</param_preferred_time>
</prefix>
</prefixes>
<addresses/>
</router>
params_volatile
Indicates if the router params may change during operation. A value of 0 means
that values do not change, a non-zero values means parameters may change. If
this tag is not present, its value is assumed to be non-zer0 (1). If you want
NDPMon to check RA parameters for this router, include the tag param_voltile
with a value of zero. If param_volatile is set to zero, you should at least
include the router param_flags_reserved tag and the param_tags for each
prefix.
param_flags_reserved
The flags of a RA or a RA prefix information option, stored as an unsigned
integer. If this tag is not present, it does not indicate that this is
unspecified, but that no flags are set!
param_curhoplimit, param_router_lifetime, param_reachable_timer,
param_retrans_timer, param_mtu
Contains the values of the corresponding RA fields (or the MTU option). If those
tags are not present, this indicates that they are not specified, and the
corresponding value of a RA will not be checked.
prefix: param_flags_reserved, param_valid_time, param_preferred_time
The parameters of prefixes advertised. These tags should be present for each
prefix if parameters are checked, because prefix parameters cannot be
unspecified. If they are not present, their value is assumed to be zero (which
is, concerning the prefix lifetimes, usually not desired).
Configuring the countermeasures plugin
Below you will find an example configuration for the countermeasures plugin. If
the tag countermeasures is not present, all countermeasures are suppressed.
<countermeasures>
<kill_illegitimate_router>RESPOND</kill_illegitimate_router>
<kill_wrong_prefix>LAUNCH AFTER 10</kill_wrong_prefix>
<propagate_router_params>CEASE AFTER 10</propagate_router_params>
<indicate_ndpmon_presence>SUPPRESS</indicate_ndpmon_presence>
</countermeasures>
SUPPRESS
The countermeasure is turned off (default value for each configuration tag not
present).
RESPOND
Each call to this countermeasure result in a reaction.
CEASE AFTER max
For max calls, each call to this countermeasure results in a reaction. After the
max'th call, the countermeasure is suppressed. max may be a number up to 255.
This may be used to precent NDPMon from contributing to a Denial of Service
attack, but to have a "first response" countermeasure.
LAUNCH AFTER min
For min calls, this countermeasure is suppressed. After the min'th call, each
call to the countermeasure results in a reaction. min may be a number up to
255.
AUTHOR¶
ndpmon was written by Thibault Cholez.
This manual page was copied from the configuration web page
(
http://ndpmon.sourceforge.net/configuration.html) by John R. Baskwill
<jrb28@psu.edu>, for the Debian project (and may be used by
others).