TITAN 3.0 FCS FAQ
1) Question: Titan isn't
as chatty as it used to be. How do I get the verbose output back?
Answer: Why would you want to? :-)
Actually, Titan and all of its modules were changed to allow you to
pick how much chattiness is appropriate for your environment /mood. I say
mood, because you may want Titan to be chatty when you first learn Titan
conventions, or you may want as much verbosity as possible when running
in verify (-v) audit mode, but there are other times when you will want
Titan to just shut up and do its thing. The verbosity of output has
been made configurable for just these reasons. To change the level of how
much verbosity output you want, modify:
$TITANDIR/lib/misc_functions.sh (TITANDIR/lib is a symlink). Change
"print_level=1" and "echo_out=t_echo.res"
#
# File name that t_echo prints to if it doesn't go to the screen
#
#echo_out="/dev/null"
echo_out="t_echo.res"
#
# t_echo (output_level, output)
#
# Where output_level is one of these:
#
# 0 = Actions done or problems
found, not even error messages
# 1 = Error messages
# 2 = Pass/fail informational,
chatty stuff
# 3 = debug
#
2) Question: Titan has a whole lot of modules that
it disables that I need left alone. How do I get Titan to only fix specific
things?
Answer: Be careful. We wrote each modules for a reason. If your either
sure you need the service, or you are willing to risk leaving it enabled,
then read on. We agree that different systems have different security needs.
A user desktop sitting behind a firewall and assuming (ass-u-me) the other
security layers are in place, and working, doesn't need all of the Titan
modules run on it. We prefer (from the security standpoint) to break things,
and then have you turn on only the services that you can't live without.
Don't despair, we have made it easy for you to accomplish this, but we
would be remiss if we didn't warn you first. If you know what your doing,
and have a good understanding of why Titan disables the things it does,
then (and only then) you are ready for building configuration files for
the different system types under your control. We honestly believe that
after a short time playing with Titan, you will be using the "-c" feature
as your default, and get the most satisfaction out of running Titan this
way. But let me stress again YOU ARE WATERING DOWN YOUR SECURITY. Okay
now lets look at a sample configuration file, and how Titan runs it. This
is a real simple sample. We call this file "simple-sample"
------------------cut---here----------------------------------------------------
# Short sample configuration file
# Titan is smart enough to not run lines starting with a "#" so
put in comments
# to remind yourself why you changed things
# You can mix and match "-f", "-v", (or -i for that matter, not
that -i makes sense
# here)
# Titan expects that each line has two arguments; the module to
run AND the run
# flag
# run the following line in "-v" verify mode. Titan only verifies
the fix is in
# place. no change is made to the system. See system audit Q&A
below!
add-umask.sh -v
# go ahead and change the file ownership's using the "-f" (fix)
flag
file-own.sh -f
# run these module as well in fix mode
utmp.sh -f
vold.sh -f
my-new-module.sh -f
------------------end sample configuration--------------------------------------
3) Question: Wait. Titan as a system audit tool? Tell me more!
Answer: YOU BET! The third biggest uses for Titan (the first
being to FIX security problems; the second is Titan's use as a security
learning tool) and the use security consultants and auditors will like
best about Titan is its ability to be run on a Unix system and report things
that may be security issues. A checklist that runs all the checks and produces
a simple report. There are three ways of accomplishing this. The
first way is to look at "TitanReport," and run it. TitanReport is designed
to run (out of cron) all Titan modules "-verify" and send the results via
e-mail. For all three of these; make sure you pre-set print_level=3. See
Question 1 above. The second way is to run Titan -v, and gathering up the
$TITANDIR/logs/* files and
the "t_echo.res" files. The third way is to build a configuration file
(audit.config) that lists out all the Titan modules you want to run "-verify"
and running "Titan -c audit.config". In this way you can use Titan to audit
firewalls, servers, and desktops using a separate configuration that matches
your security policy (you do have a security policy don't you?)
We encourage you to use the Titan framework, and write your own modules.
If you do, please donate them to Titan. We will take all modules and incorporate
them into the next release of Titan.
4) Question: Which Modules should I use
for a Server, a Firewall, A desktop?
Answer: That depends. Take a look at Server.config,
Firewall.config, and Desktop.config
Here are my recommendations broken down
by OS.
SunOS 4.1.X
Firewall -
All titan modules
should be run and then some! I'd walk through /etc/rc.local and /etc/rc
and disable everything that you didn't want to run at start-up time. Also
consider running ASET in the tune-high mode. Additionally look in the optional
directory for the patch to turn off forwarding of source routed packets.
Server
Run all titan modules
except possibly routed.sh if the system is a router.
Also run tftpServer.sh if the system is a diskless
workstation server, or run tftp-disable.sh if the system does not boot
diskless workstations. Check aliases.sh and decode.sh one may be more restrictive
than your policy allows. Inetd.conf.sh might need to be modified. Also
consider running ASET in the tune-med mode
Desktop
Run all titan scripts
except tftpServer.sh. Inetd.conf.sh might need to be modified. Also consider
running ASET in the tune-low mode
Solaris 2.X
Firewall -
All titan modules
should be run and then some. You might want to turn off sendmail for instance
completely, on the firewall and just pass mail to a protected mailserver.
All other titan modules should be run with the following caveat. On a Proxy
firewall such as TIS that doesn't have a Windowing System GUI (curses based
GUI) All titan modules can be run and in fact I would also either do a
fresh install of the OS and only install the "core" unix utilities or do
a pkgrm of all the un-needed utilities. DO NOT RUN anon-ftp.sh unless the
systems is supposed to be an anonymous ftp server.
So
what are the "unneeded" utilities? I can't answer that without knowing
what you are going to use the firewall for in more details. Here instead
is a list of Solaris 2.X utilities that you should think about removing
from a Proxy firewall.
Any
of the Compiler utilities. You shouldn't be compiling on the firewall.
You also don't want crackers (cracker = criminal hacker) being able to
compile things on your firewall. (note you might make the compile utilities
directory mode 700 owned by root; if you have to compile on the firewall)
All
of the System administration applications as well as the System and network
administration packages. These are made for remote administration. Why
risk having someone else remotely administering your firewall?
All
the Audio applications unless you have some sort of audio alert set up
to detect intrusion attempts (doubtful)
All
the SunOS Binary Compatibility packages. its amazing how many older breaking
tools will no longer work if this package isn't available.
All
the CC/GCC tools (used by the compiler) compile somewhere else or at least
have a build directory that is mode 0700 owned by root. If intruder can
compile on your system then, well, you have already lost.
Unless
your using a GUI *on* the firewall system (such as running FW-1 GUI; fwui
locally) then you can remove all of the GX cg6 device drivers.
Again
if your not using any GUI, then remove all the CDE (common desktop environment)
windowing
system stuff. Note; you can still re-display GUI application to a remote
server without this being installed.
Remove
all the DT (desktop login environment).
Remove
all the HotJava browser portions
Remove
all the UTF-8 unless your using a GUI *on* the Firewall system.
If
you are not using the Federated naming System (man fns) then remove all
the references to this such as SUNWfns
Remove
all the SunOS header files support unless for some reason your using binaries
compiled from a SunOS system. This also applies to the binary compatibility
packages.
All
the X11 fonts also go unless you run a windowing system locally
Any
Java support unless you run java locally (a DMZ Web server might; but the
Firewall shouldn't)
Remove
all the KCMS support unless your using a GUI (even then consider it)
Any
of the WorkShop support can be removed unless you run a Sun workshop application
(such as the C compiler not recommended to be run on the firewall)
The
FlexLM (License Manager) may need to be there so that licensed software
packages can run (FW-1). However if you don't need it, this is one less
daemon running and should be considered for removal. Proxy firewalls most
often don't need the license manager daemon.
On
a firewall system the LP services can often be removed unless you run a
local printer to capture hard copy of log files. If you leave this installed,
you should disable LP unless you actually run a (line) printer. Some sites
leave this installed but disabled until it is needed e.g., until a break-in
and a need for stringent logging.
All
the Motif support can be removed unless the CDE window system is run.
The
SNMP agents are most commonly removed or disabled on a firewall system.
This is because they can give out information to intruders. Unless you
are using SNMP to send alerts to an internal system, then remove the SNMP
packages. If you do use SNMP alerts, make sure and block SNMP on the external
router.
NIS
can often (and should be) removed from the firewall system. Exceptions
are older SunOS 4.1.X systems which needed NIS to run for DNS to work.
If you don't need it; remove it.
The
NTP support is the Network Time Protocol. If you use NTP to synchronize
clocks, leave this in. Systems that might use this are Digital Token Databases
that use time displays (Security Dynamics) or you may be using an atomic
clock service to synchronize your Server or internal systems clocks. if
you do use xntpd or NTP services you should most likely wrapper the service
so that only specific trusted locations can modify your systems sense of
reality. An interesting attack would be to reset the system clock back
20 minutes so that a time based token becomes valid again.
Open
Windows and open look packages can be removed on Proxy Firewalls without
a GUI, as well as Firewall Systems that don't manage the firewall via local
GUI.
The
Power management support can be removed on a firewall. I don't know of
any firewalls that should shut themselves down after N minutes of idle
time. However powerd can be used to shutdown systems on low power conditions.
If you use UPS and don't use another software package supplied by the UPS
vendor, powerd might be useful to have. If you do leave this running make
sure and wrapper the service.
The
Solstice Enterprise agent can probably be removed as well.
Sparc
Compilers binary compatibility can be removed unless you are cross compiling
SunOS binaries on your firewall (not recommended)
The
Solaris Naming Enabler I can't find what it does.
Spell
Checking Engine can probably be removed from most firewalls
SUNWsregu
can be removed
SUNWsrh
can be removed
All
the ToolTalk utilities can be removed
All
the vold utilities can be removed unless you are lazy about mounting floppies
or CD's.
All
the XGL, XIL, and X window system can be removed unless you run a local
GUI.
Server
All titan modules
should be run except the following.
anon-ftp.setup.sh
should only be run on a system that you want people to anonymously ftp
to (limited number of systems).
lpsched.sh
should be left on if the system is a print server or if persons login and
print from the system.
nsswitch.sh
may need to be modified for Servers if NIS or DNS is being used.
disable_ip_holes
may need to be modified if the Server is a router. You will probably want
to allow the ip_forwarding in this case.
The
snpmdx and dmi titan modules would not be run if the system was being remotely
monitored/managed via SNMP.
inetd.sh
may need to be modified if other services that run out of inetd.conf are
required on the server.
routed.sh
would not be run on a Server system that was acting as a router.
vold.sh
would not be run on a system where users were allowed to mount software
from floppy or CD media. Caution should be taken that they can't mount
a suid root copy of ksh and thus bypass security. That is why you might
want to disable vold.
ziplock.sh
should probably NOT be run on any system that isn't a firewall system.
And then only on a proxy or tightly controlled system.
Desktop
All
titan modules can be run except the following.
anon-ftp.setup.sh
should not be run.
automount.sh
may be left on if the Automounter of file systems is permitted
inetd.sh
may need to be modified if things like calendar manager is run on the desktop
lpsched.sh
might be left on so users can print.
nsswitch.sh
may need to be modified if DNS and NIS is used.
vold.sh
should not be run if users are allowed to mount floppies or CD's locally
ziplock.sh
should NOT be run on desktops.
Note- depending on the
windowing system used you may need to leave on some RPC services
5) Question: Why the SCCS directories?
Answer: The intent is so that if changes are
made to titan modules we have a record of who did what and when. SCCS was
used instead of other source control modules because most all unicies have
SCCS. e.g., its the lowest common denominator.
6 )Question: How do I build my own titan module?
Answer: Start out with the arch/sol2sun4/src/stubs/skeleton
script. It was put there for just that reason. Lets examine it in detail.
The first line ":" this character is similar
to using "#!/bin/sh" the difference is that it is possible that "sh" doesn't
live in "/bin" thus if we use ":" we tell the system to use the kernel
default shell which for unix is the bourn shell "sh"
The second line sets the umask value so that
any files created by the script have a sane default file mask.
The next few lines are Copyright and License
notices and required for legal purposes.
#
umask 022
# This tool suite was written
by and is copyright by Brad Powell Dan Farmer, and
# Matt Archibald 1992, 1993,
1994, 1995, 1996, 1997, 1998 with input
# from Casper Dik, and Alec
Muffett.
# The copyright holder disclaims
all responsibility or liability with
# respect to its usage or
its effect upon hardware or computer
# systems, and maintains
copyright as set out in the "LICENSE"
# document which accompanies
distribution.
Next we have a setup section and the sanity
check section. We use "MYNAME" so that error messages will echo the name
of the script that the error occurred from. The sanity check calls the
sub-script "sanity_check" which checks for execution by "root" as well
as checks that the user passed the required number of arguments (-Verify,
-Intro, -Fix)
# did things work out
or not?
action=`./sanity_check
$MYNAME $1`
if test $? -ne root;
then
exit 1
fi
The next part of a titan module is the Introduction
section Intro(). We use a simple trick so that any text you place between
the "EOF_INTRO" keywords gets echoed to the screen when the user starts
a titan script with the "-i", "-I" or "-Introduction" flag. e.g., if a
user runs "add_umask.sh -i" all the lines in the add_umask.sh script between
the "EOF_INTRO" words are displayed to his/her terminal using the cat command.
The next section of a titan script is the Check()
function. This is the pert of the script that is used when a titan script
is run in the "-v" verify mode. Look through a few of the titan scripts
to see some of the ways the Check() function checks out the system. The
only standard thing that titan does in a Check() function is to produce
a "PASSES CHECK" or a "FAILS CHECK" so users can figure out if this titan
fix is needed or already applied to the system. Notice that all three sections
Intro(), Check(), and Fix() are bound by brackets "{and}" at the beginning
and end of the function. Example Check function using a simple if, then,
else, fi sequence.
Check() {
if [ -f /etc/init.d/init.dmi
]; then
echo " dmi daemon is
enabled: FAILS CHECK"
exit 1
else
echo " dmi doesn't start
at boot time: PASSES CHECK"
fi
}
The next portion of a titan script is the Fix()
function. This is where we actually change or modify system files. This
function is only invoked when the user specifically runs a titan script
with the "-f", "-F", "-fix" flag. The structure is similar to the Intro()
and Check() structure but commonly has more lines since files are modified.
Example Fix() function which moves and renames start-up files so that on
system boot these scripts are no longer run by the system; thus disabling
that function. Again we use a simple if, then, else, fi sequence.
Fix() {
if [ -f /etc/init.d/init.dmi
]; then
echo " Saving /etc/init.d/init.dmi
to /etc/init.d-init.dmi.ORIG"
/bin/mv /etc/init.d/init.dmi
/etc/init.d-init.dmi.ORIG.$$
/bin/mv /etc/rc2.d/K77dmi
/etc/rc2.d-K77dmi.ORIG.$$
/bin/mv /etc/rc3.d/S77dmi
/etc/rc3.d/S77dmi.ORIG.$$
chmod 0100 /etc/init.d-init.dmi.ORIG.$$
chmod 0100 /etc/rc2.d-K77dmi.ORIG.$$
chmod 0100 /etc/rc3.d/S77dmi.ORIG.$$
if [ $? -ne 0 ]; then
echo " ERROR: Could not
rename /etc/rc3.d/S77dmi ; exiting"
exit 1
else
echo "Done ... "
fi
fi
}
The last section of a titan script is the action
section. This is pretty generic for all scripts. We basically check to
see which flag the user specified and then run that function. e.g. if the
user typed "foo.sh -f" then we run the Fix() function. If the users types
anything that isn't a n "-i, -v, -f" (capital or lower case) then we simply
print out an error message with the usage lines and exit.
That is basically it.
There are a few other functions you should
be aware of.
The "Titan-Config" (Titan-Config -i" (install) script figures out your
OS type and makes links to the proper Titan modules. Titan-Config also asks
if you want to create a backup of all the files Titan modifies. This is
needed in the event you want to recover from titan being too aggressive
about security and breaking some of your functionality. The untit.sh utility
is called when "Titan-Config -d" (de-install) is used. Untit.sh removes all
changes Titan performed (assuming you made a backup when you ran "Titan-Config
-i"
The Titan script runs *all* commands in the
$TITANDIR/bin/modules directory that are
a) a file, and b) are executable. Thus you can move all the scripts
that you don't want run to another location or simply change the mode of
the file, and Titan will not run them.
Example: By just creating a new script called
"runme.sh" which accepts the standard titan arguments (-i, -v or -f) and
putting it into the $TITANDIR/bin/modules directory, and calling "Titan
-F" would cause all the scripts that are in the $TITANDIR/bin/modules
directory to be run with the "-f" flag including your new module.
Example2: Removing all the scripts except script
a.sh, b.sh, c.sh and running "Titan -v" would cause titan to only run a.sh,
b.sh, and c.sh with the "-v "flag. No other script would be run. An easier
way would be to build a configuration file and list the modules you want
run including the run flag, and running "Titan -c config.file"
misc_functions.sh is there so that you can use the t_echo (t_echo
[0,1,2,3]) function to set the level of verbosity on the output of your
script.
sanity_check script is there so that you don't
have to build that functionality into your script, all you need do is supply
the MYNAME, and call sanity_check from your new titan script.
MYNAME=`basename $0`
# did things work out
or not?
action=`./sanity_check
$MYNAME $1`
if test $? -ne root ;
then
exit 1
fi
Lastly the is_root sub-function is called by
the sanity_check script to check and report if the caller is running as
root.
7) Question: Where do I get the latest version of titan?
Answer: http://trouble.org/titan/index.html
8) Question: If I write a titan module and want to share it, how do
I get it into the next release?
Answer: Send a message to titan@trouble.org
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Documentation Page
Last Modified: 0:00 PDT, October 31, 1998