#!/bin/bash # # Security level implementation... # Writen by Vandoorselaere Yoann # if [[ -f /usr/share/msec/lib.sh ]]; then . /usr/share/msec/lib.sh else echo "Can't find /usr/share/msec/lib.sh, exiting." exit 1 fi # Log in append only mode echo -e "Changing attribute of /var/log/* to append only...\n" # All events logged on tty12 echo "Loging all messages on tty12 : " AddRules "*.* /dev/tty12" /etc/syslog.conf # Prevent all kind of connection except from localhost echo "Denying all kind of connection except localhost : " AddRules "ALL:ALL EXCEPT localhost:DENY" /etc/hosts.deny # Login as root on the console allowed : echo "Denying login as root (except on the console) :" AddRules "tty1" /etc/securetty quiet AddRules "tty2" /etc/securetty quiet AddRules "tty3" /etc/securetty quiet AddRules "tty4" /etc/securetty quiet AddRules "tty5" /etc/securetty quiet AddRules "tty6" /etc/securetty AddRules "vc/1" /etc/securetty quiet AddRules "vc/2" /etc/securetty quiet AddRules "vc/3" /etc/securetty quiet AddRules "vc/4" /etc/securetty quiet AddRules "vc/5" /etc/securetty quiet AddRules "vc/6" /etc/securetty # Security check echo "Updating file check variable : " echo -e "\t- Check security : yes." AddRules "CHECK_SECURITY=yes" /etc/security/msec/security.conf quiet echo -e "\t- Check important permissions : yes." AddRules "CHECK_PERMS=yes" /etc/security/msec/security.conf quiet echo -e "\t- Check suid root file : yes." AddRules "CHECK_SUID_ROOT=yes" /etc/security/msec/security.conf quiet echo -e "\t- Check suid root file integrity (backdoor check) : yes." AddRules "CHECK_SUID_MD5=yes" /etc/security/msec/security.conf quiet echo -e "\t- Check suid group file : yes." AddRules "CHECK_SUID_GROUP=yes" /etc/security/msec/security.conf quiet echo -e "\t- Check world writable file : yes." AddRules "CHECK_WRITEABLE=yes" /etc/security/msec/security.conf quiet echo -e "\t- Check unowned file : yes." AddRules "CHECK_UNOWNED=yes" /etc/security/msec/security.conf quiet echo -e "\t- Check promiscuous mode : yes." AddRules "CHECK_PROMISC=yes" /etc/security/msec/security.conf quiet echo -e "\t- Check listening port : yes." AddRules "CHECK_OPEN_PORT=yes" /etc/security/msec/security.conf quiet echo -e "\t- Check passwd file integrity : yes." AddRules "CHECK_PASSWD=yes" /etc/security/msec/security.conf quiet echo -e "\t- Check shadow file integrity : yes." AddRules "CHECK_SHADOW=yes" /etc/security/msec/security.conf quiet echo -e "\t- Security warning on tty : yes." AddRules "TTY_WARN=yes" /etc/security/msec/security.conf quiet echo -e "\t- Security warning by mail : yes." AddRules "MAIL_WARN=yes" /etc/security/msec/security.conf quiet AddRules "MAIL_USER=root" /etc/security/msec/security.conf quiet echo -e "\t- Security warning in syslog : yes." AddRules "SYSLOG_WARN=yes" /etc/security/msec/security.conf # end security check # Check every 1 minutes for promisc problem echo "Adding promisc check in crontab (scheduled every minutes) :" AddRules "*/1 * * * * root /usr/share/msec/promisc_check.sh" /etc/crontab echo "Adding \"diff\" & \"global\" security check in crontab (scheduled every midnight) :" AddRules "0 4 * * * root /usr/share/msec/security.sh" /etc/crontab # Server update export SECURE_LEVEL=4 echo "Setting secure level variable to 4 :" AddRules "SECURE_LEVEL=4" /etc/sysconfig/msec IFS=" " echo -n "Disabling all service, except : {" for service in `chkconfig --list | awk '{print $1}'`; do if grep -qx ${service} /etc/security/msec/server.4; then echo -n " ${service}" fi done echo " } : " for service in `chkconfig --list | awk '{print $1}'`; do chkconfig --del "${service}" if ! chkconfig --msec --add "${service}"; then echo -e "\t- Services ${service} scheduled to be disabled at next boot." fi done echo -e "done.\n"; echo "Setting umask to 022 (u=rw,g=rx) for root, 077 (u=rw) for user :" AddRules "UMASK_ROOT=022" /etc/sysconfig/msec AddRules "UMASK_USER=077" /etc/sysconfig/msec if [[ -f /lib/libsafe.so.2 ]]; then echo "Enabling stack overflow protection :" AddRules "/lib/libsafe.so.2" /etc/ld.so.preload fi # Console timeout echo "Setting console timeout :" AddRules "TMOUT=7200" /etc/sysconfig/msec # No history file echo "No history file :" AddRules "HISTFILESIZE=0" /etc/sysconfig/msec # Ip spoofing protection echo "IP spoofing protection :" AddRules "nospoof on" /etc/host.conf AddRules "spoofalert on" /etc/host.conf # icmp echo echo "Ignoring icmp echo :" AddRules "net.ipv4.icmp_echo_ignore_all=1" /etc/sysctl.conf AddRules "net.ipv4.icmp_echo_ignore_broadcasts=1" /etc/sysctl.conf # bad error echo "Enabling bad error message Protection :" AddRules "net.ipv4.icmp_ignore_bogus_error_responses=1" /etc/sysctl.conf # log strange packets echo "Enabling logging Spoofed Packets, Source Routed Packets, Redirect Packets :" AddRules "net.ipv4.conf.all.log_martians=1" /etc/sysctl.conf LoadSysctl # issues echo "Removing /etc/issue.net :" RemoveIssueNet # Do not boot on a shell ForbidReboot ForbidAutologin # Group were modified in lib.sh... grpconv ForbidUserList RootSshLogin 4