17.4. Configure the /usr/TSS/policy/twpol.txt file

You must modify the default policy file, or create your own. The policyguide.txt file under /usr/TSS/policy directory can help you. Open the policy file twpol.txt with a text editor, vi /usr/TSS/policy/twpol.txt and change it to fit your needs:

@@section GLOBAL TWROOT="/usr"; TWBIN="/usr/bin"; TWPOL="/usr/TSS/policy"; TWDB="/usr/TSS/db"; TWSKEY="/usr/TSS/key"; TWLKEY="/usr/TSS/key"; TWREPORT="/usr/TSS/report"; HOSTNAME=deep.openna.com; @@section FS SEC_CRIT = $(IgnoreNone)-SHa; # Critical files - we can't afford to miss any changes. SEC_SUID = $(IgnoreNone)-SHa; # Binaries with the SUID or SGID flags set. SEC_TCB = $(ReadOnly); # Members of the Trusted Computing Base. SEC_BIN = $(ReadOnly); # Binaries that shouldn't change SEC_CONFIG = $(Dynamic); # Config files that are changed infrequently but accessed often. SEC_LOG = $(Growing); # Files that grow, but that should never change ownership. SEC_INVARIANT = +pug; # Directories that should never change permission or ownership. SIG_LOW = 33; # Non-critical files that are of minimal security impact SIG_MED = 66; # Non-critical files that are of significant security impact SIG_HI = 100; # Critical files that are significant points of vulnerability # Tripwire Binaries (emailto = [email protected], rulename = "Tripwire Binaries", severity = $(SIG_HI)) { $(TWBIN)/siggen -> $(ReadOnly); $(TWBIN)/tripwire -> $(ReadOnly); $(TWBIN)/twadmin -> $(ReadOnly); $(TWBIN)/twprint -> $(ReadOnly); } # Tripwire Data Files - Configuration Files, Policy Files, Keys, Reports, Databases (emailto = [email protected], rulename = "Tripwire Data Files", severity = $(SIG_HI)) { # NOTE: Removing the inode attribute because when Tripwire creates a backup # it does so by renaming the old file and creating a new one (which will # have a new inode number). Leaving inode turned on for keys, which shouldn't # ever change. # NOTE: this rule will trigger on the first integrity check after database # initialization, and each integrity check afterward until a database update # is run, since the database file will not exist before that point. $(TWDB) -> $(Dynamic) -i; $(TWPOL)/tw.pol -> $(SEC_BIN) -i; $(TWBIN)/tw.cfg -> $(SEC_BIN) -i; $(TWLKEY)/$(HOSTNAME)-local.key -> $(SEC_BIN) ; $(TWSKEY)/site.key -> $(SEC_BIN) ; #don't scan the individual reports $(TWREPORT) -> $(Dynamic) (recurse=0); } # These files are critical to a correct system boot. (emailto = [email protected], rulename = "Critical system boot files", severity = 100) { /boot -> $(SEC_CRIT) ; !/boot/System.map ; !/boot/module-info ; } # These files change the behavior of the root account (emailto = [email protected], rulename = "Root config files", severity = 100) { /root -> $(SEC_CRIT) ; /root/.bash_history -> $(SEC_LOG) ; } # Commonly accessed directories that should remain static with regards to owner and group (emailto = [email protected], rulename = "Invariant Directories", severity = $(SIG_MED)) { / -> $(SEC_INVARIANT) (recurse = 0); /home -> $(SEC_INVARIANT) (recurse = 0); /etc -> $(SEC_INVARIANT) (recurse = 0); /chroot -> $(SEC_INVARIANT) (recurse = 0); /cache -> $(SEC_INVARIANT) (recurse = 0); } (emailto = [email protected], rulename = "Shell Binaries") { /bin/bsh -> $(SEC_BIN); /bin/csh -> $(SEC_BIN); /bin/sh -> $(SEC_BIN); } # Rest of critical system binaries (emailto = [email protected], rulename = "OS executables and libraries", severity = $(SIG_HI)) { /bin -> $(ReadOnly) ; /lib -> $(ReadOnly) ; } # Local files (emailto = [email protected], rulename = "User binaries", severity = $(SIG_MED)) { /sbin -> $(SEC_BIN) (recurse = 1); /usr/sbin -> $(SEC_BIN) (recurse = 1); /usr/bin -> $(SEC_BIN) (recurse = 1); } # Temporary directories (emailto = [email protected], rulename = "Temporary directories", recurse = false, severity = $(SIG_LOW)) { /usr/tmp -> $(SEC_INVARIANT); /var/tmp -> $(SEC_INVARIANT); /tmp -> $(SEC_INVARIANT); } # Libraries (emailto = [email protected], rulename = "Libraries", severity = $(SIG_MED)) { /usr/lib -> $(SEC_BIN); } # Include (emailto = [email protected], rulename = "OS Development Files", severity = $(SIG_MED)) { /usr/include -> $(SEC_BIN); } # Shared (emailto = [email protected], rulename = "OS Shared Files", severity = $(SIG_MED)) { /usr/share -> $(SEC_BIN); } # Kernel headers files (emailto = [email protected], rulename = "Kernel Headers Files", severity = $( SIG_HI)) { /usr/src/linux-2.2.14 -> $(SEC_BIN); } # setuid/setgid root programs (emailto = [email protected], rulename = "setuid/setgid", severity = $(SIG_HI)) { /bin/su -> $(SEC_SUID); /sbin/pwdb_chkpwd -> $(SEC_SUID); /sbin/dump -> $(SEC_SUID); /sbin/restore -> $(SEC_SUID); /usr/bin/at -> $(SEC_SUID); /usr/bin/passwd -> $(SEC_SUID); /usr/bin/suidperl -> $(SEC_SUID); /usr/bin/crontab -> $(SEC_SUID); /usr/sbin/sendmail -> $(SEC_SUID); /usr/bin/man -> $(SEC_SUID); /usr/bin/sperl5.00503 -> $(SEC_SUID); /usr/bin/slocate -> $(SEC_SUID); /usr/sbin/utempter -> $(SEC_SUID); /sbin/netreport -> $(SEC_SUID); } (emailto = [email protected], rulename = "Configuration Files") { /etc/hosts -> $(SEC_CONFIG); /etc/inetd.conf -> $(SEC_CONFIG); /etc/initlog.conf -> $(SEC_CONFIG); /etc/inittab -> $(SEC_CONFIG); /etc/resolv.conf -> $(SEC_CONFIG); /etc/syslog.conf -> $(SEC_CONFIG); } (emailto = [email protected], rulename = "Security Control") { /etc/group -> $(SEC_CRIT); /etc/security/ -> $(SEC_CRIT); /lib/security/ -> $(SEC_CRIT); /var/spool/cron -> $(SEC_CRIT); } (emailto = [email protected], rulename = "Login Scripts") { /etc/csh.login -> $(SEC_CONFIG); /etc/profile -> $(SEC_CONFIG); } # These files change every time the system boots (emailto = [email protected], rulename = "System boot changes", severity = $(SIG_HI)) { /dev/log -> $(Dynamic) ; /dev/cua0 -> $(Dynamic) ; /dev/console -> $(Dynamic) ; /dev/tty2 -> $(Dynamic) ; # tty devices /dev/tty3 -> $(Dynamic) ; # are extremely /dev/tty4 -> $(Dynamic) ; # variable /dev/tty5 -> $(Dynamic) ; /dev/tty6 -> $(Dynamic) ; /dev/urandom -> $(Dynamic) ; /dev/initctl -> $(Dynamic) ; /var/lock/subsys -> $(Dynamic) ; /var/run -> $(Dynamic) ; # daemon PIDs /var/log -> $(Dynamic) ; /etc/ioctl.save -> $(Dynamic) ; /etc/.pwd.lock -> $(Dynamic) ; /etc/mtab -> $(Dynamic) ; /lib/modules -> $(Dynamic) ; } # Critical configuration files (emailto = [email protected], rulename = "Critical configuration files", severity = $(SIG_HI)) { /etc/conf.modules -> $(ReadOnly) ; /etc/crontab -> $(ReadOnly) ; /etc/cron.hourly -> $(ReadOnly) ; /etc/cron.daily -> $(ReadOnly) ; /etc/cron.weekly -> $(ReadOnly) ; /etc/cron.monthly -> $(ReadOnly) ; /etc/default -> $(ReadOnly) ; /etc/fstab -> $(ReadOnly) ; /etc/group- -> $(ReadOnly) ; # changes should be infrequent /etc/host.conf -> $(ReadOnly) ; /etc/hosts.allow -> $(ReadOnly) ; /etc/hosts.deny -> $(ReadOnly) ; /etc/lilo.conf -> $(ReadOnly) ; /etc/logrotate.conf -> $(ReadOnly) ; /etc/pwdb.conf -> $(ReadOnly) ; /etc/securetty -> $(ReadOnly) ; /etc/sendmail.cf -> $(ReadOnly) ; /etc/protocols -> $(ReadOnly) ; /etc/services -> $(ReadOnly) ; /etc/rc.d/init.d -> $(ReadOnly) ; /etc/rc.d -> $(ReadOnly) ; /etc/motd -> $(ReadOnly) ; /etc/passwd -> $(ReadOnly) ; /etc/passwd- -> $(ReadOnly) ; /etc/profile.d -> $(ReadOnly) ; /etc/rpc -> $(ReadOnly) ; /etc/sysconfig -> $(ReadOnly) ; /etc/shells -> $(ReadOnly) ; /etc/nsswitch.conf -> $(ReadOnly) ; } # Critical devices (emailto = [email protected], rulename = "Critical devices", severity = $(SIG_HI), recurse = false) { /dev/kmem -> $(Device) ; /dev/mem -> $(Device) ; /dev/null -> $(Device) ; /dev/zero -> $(Device) ; /proc/devices -> $(Device) ; /proc/net -> $(Device) ; /proc/tty -> $(Device) ; /proc/sys -> $(Device) ; /proc/cpuinfo -> $(Device) ; /proc/modules -> $(Device) ; /proc/mounts -> $(Device) ; /proc/dma -> $(Device) ; /proc/filesystems -> $(Device) ; /proc/ide -> $(Device) ; /proc/interrupts -> $(Device) ; /proc/ioports -> $(Device) ; /proc/scsi -> $(Device) ; /proc/kcore -> $(Device) ; /proc/self -> $(Device) ; /proc/kmsg -> $(Device) ; /proc/stat -> $(Device) ; /proc/ksyms -> $(Device) ; /proc/loadavg -> $(Device) ; /proc/uptime -> $(Device) ; /proc/locks -> $(Device) ; /proc/version -> $(Device) ; /proc/meminfo -> $(Device) ; /proc/cmdline -> $(Device) ; /proc/misc -> $(Device) ; }

Once you are ready to use your policy file for the first time, install it with the following command:

[root@deep] /#twadmin --create-polfile /usr/TSS/policy/twpol.txt

Please enter your site passphrase: Wrote policy file: /usr/TSS/policy/tw.pol