root/psad/tags/psad-2.1.2/install.pl

#!/usr/bin/perl -w
#
#########################################################################
#
# File: install.pl
#
# Purpose:  install.pl is the installation script for psad.  It is safe
#           to execute install.pl even if psad has already been installed
#           on a system since install.pl will preserve the existing
#           config section within the new script.
#
# Credits:  (see the CREDITS file)
#
# Copyright (C) 1999-2008 Michael Rash (mbr@cipherdyne.org)
#
# License (GNU Public License):
#
#    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
#
# TODO:
#
#########################################################################
#
# $Id$
#

use Cwd;
use File::Path;
use File::Copy;
use Sys::Hostname;
use IO::Socket;
use Getopt::Long;
use strict;

#============== config ===============
my $USRSBIN_DIR  = '/usr/sbin';  ### consistent with FHS (Filesystem
                                 ### Hierarchy Standard)
my $USRBIN_DIR   = '/usr/bin';   ### consistent with FHS

my $psad_conf_file  = 'psad.conf';

### system binaries ###
my $chkconfigCmd = '/sbin/chkconfig';
my $rcupdateCmd  = '/sbin/rc-update';  ### Gentoo
my $updatercdCmd = '/usr/sbin/update-rc.d';  ### Ubuntu
my $makeCmd      = '/usr/bin/make';
my $perlCmd      = '/usr/bin/perl';
my $wgetCmd      = '/usr/bin/wget';
my $runlevelCmd  = '/sbin/runlevel';
#============ end config ============

my %file_vars = (
    'signatures'    => 'SIGS_FILE',
    'auto_dl'       => 'AUTO_DL_FILE',
    'icmp_types'    => 'ICMP_TYPES_FILE',
    'posf'          => 'POSF_FILE',
    'pf.os'         => 'P0F_FILE',
    'snort_rule_dl' => 'SNORT_RULE_DL_FILE',
    'ip_options'    => 'IP_OPTS_FILE'
);

my %exclude_cmds = (
    'wget'         => '',
    'mail'         => '',
    'sendmail'     => '',
    'uname'        => '',
    'df'           => '',
    'psadwatchd'   => '',
    'kmsgsd'       => '',
    'psad'         => '',
    'whois'        => '',
    'fwcheck_psad' => ''
);

### map perl modules to versions
my %required_perl_modules = (
    'Unix::Syslog' => {
        'force-install' => 0,
        'mod-dir' => 'Unix-Syslog'
    },
    'Bit::Vector' => {
        'force-install' => 0,
        'mod-dir' => 'Bit-Vector'
    },
    'Storable', => {
        'force-install' => 0,
        'mod-dir' => 'Storable'
    },
    'Date::Calc', => {
        'force-install' => 0,
        'mod-dir' => 'Date-Calc'
    },
    'Net::IPv4Addr' => {
        'force-install' => 0,
        'mod-dir' => 'Net-IPv4Addr'
    },
    'IPTables::Parse' => {
        'force-install' => 1,
        'mod-dir' => 'IPTables-Parse'
    },
    'IPTables::ChainMgr' => {
        'force-install' => 1,
        'mod-dir' => 'IPTables-ChainMgr'
    },
);

my %config = ();
my %cmds   = ();

my @cmd_search_paths = qw(
    /bin
    /sbin
    /usr/bin
    /usr/sbin
    /usr/local/bin
    /usr/local/sbin
);

### IP regex
my $ip_re = qr|(?:[0-2]?\d{1,2}\.){3}[0-2]?\d{1,2}|;

### get the hostname of the system
my $HOSTNAME = hostname();

my $src_dir = getcwd() or die "[*] Could not get current working directory.";

### for user answers
my $ACCEPT_YES_DEFAULT = 1;
my $ACCEPT_NO_DEFAULT  = 2;
my $NO_ANS_DEFAULT     = 0;

### set the default execution flags and command line args
my $noarchive   = 0;
my $uninstall   = 0;
my $help        = 0;
my $archived_old = 0;
my $skip_syslog_test = 0;
my $skip_module_install   = 0;
my $cmdline_force_install = 0;
my $force_path_update = 0;
my $force_mod_re = '';
my $exclude_mod_re = '';
my $no_rm_old_lib_dir = 0;
my $syslog_conf = '';
my $locale = 'C';  ### default LC_ALL env variable
my $no_locale = 0;
my $init_dir = '/etc/init.d';
my $init_name = 'psad';
my $runlevel = -1;

### make Getopts case sensitive
Getopt::Long::Configure('no_ignore_case');

&usage(1) unless (GetOptions(
    'config=s'          => \$psad_conf_file,  ### specify path to psad.conf
    'force-mod-install' => \$cmdline_force_install,  ### force install of all modules
    'Force-mod-regex=s' => \$force_mod_re,  ### force specific mod install with regex
    'Exclude-mod-regex=s' => \$exclude_mod_re, ### exclude a particular perl module
    'path-update'       => \$force_path_update, ### update command paths
    'Skip-mod-install'  => \$skip_module_install,
    'no-rm-lib-dir'     => \$no_rm_old_lib_dir, ### remove any old /usr/lib/psad dir
    'no-preserve'       => \$noarchive,   ### Don't preserve existing configs.
    'syslog-conf=s'     => \$syslog_conf, ### specify path to syslog config file.
    'no-syslog-test'    => \$skip_syslog_test,
    'uninstall'         => \$uninstall,   ### Uninstall psad.
    'init-dir=s'        => \$init_dir,
    'init-name=s'       => \$init_name,
    'runlevel=i'        => \$runlevel,
    'LC_ALL=s'          => \$locale,
    'no-LC_ALL'         => \$no_locale,
    'help'              => \$help         ### Display help.
));
&usage(0) if $help;

### set LC_ALL env variable
$ENV{'LC_ALL'} = $locale unless $no_locale;

### import paths from default psad.conf
&import_config();

my @LOGR_FILES   = (*STDOUT, $config{'INSTALL_LOG_FILE'});

$force_mod_re = qr|$force_mod_re| if $force_mod_re;
$exclude_mod_re = qr|$exclude_mod_re| if $exclude_mod_re;

$cmds{'make'}     = $makeCmd;
$cmds{'perl'}     = $perlCmd;
$cmds{'runlevel'} = $runlevelCmd;

if (-e $config{'INSTALL_LOG_FILE'}) {
    open INSTALL, "> $config{'INSTALL_LOG_FILE'}" or
        die "[*] Could not open $config{'INSTALL_LOG_FILE'}: $!";
    close INSTALL;
}

my $distro = &get_distro();

if ($distro eq 'redhat' or $distro eq 'fedora') {
    ### add chkconfig only if we are runing on a redhat distro
    $cmds{'chkconfig'} = $chkconfigCmd;
} elsif ($distro eq 'gentoo') {
    ### add rc-update if we are running on a gentoo distro
    $cmds{'rc-update'} = $rcupdateCmd;
} elsif ($distro eq 'ubuntu') {
    ### add update-rc.d if we are running on an ubuntu distro
    $cmds{'update-rc.d'} = $updatercdCmd;
}

unless (-d $init_dir) {
    if (-d '/etc/rc.d/init.d') {
        $init_dir = '/etc/rc.d/init.d';
    } elsif (-d '/etc/rc.d') {  ### for Slackware
        $init_dir = '/etc/rc.d';
    } else {
        die "[*] Cannot find the init script directory, use ",
            "--init-dir <path>\n";
    }
}

### need to make sure this exists before attempting to
### write anything to the install log.
mkdir $config{'PSAD_DIR'}, 0500 unless -d $config{'PSAD_DIR'};

### make sure the system binaries are where we expect
### them to be.
&check_commands();

### check to make sure we are running as root
$< == 0 && $> == 0 or die "You need to be root (or equivalent UID 0",
    " account) to install/uninstall psad!\n";

### occasionally things from old psad installations need to be
### dealt with separately.
&check_old_psad_installation();

if ($uninstall) {
    &uninstall();
} else {
    &install();
}
exit 0;
#================= end main =================

sub install() {

    ### make sure install.pl is being called from the source directory
    unless (-e 'psad' and -d 'IPTables-ChainMgr') {
        die "[*] install.pl can only be executed from the directory\n",
            "    that contains the psad sources!  Exiting.";
    }
    &logr('[+] ' . localtime() . " Installing psad on hostname: $HOSTNAME\n");

    ### make sure another psad process is not running
    if (&ask_to_stop_psad()) {
        &stop_psad();
    }

    unless (-d $config{'PSAD_RUN_DIR'}) {
        &logr("[+] Creating $config{'PSAD_RUN_DIR'}\n");
        mkdir $config{'PSAD_RUN_DIR'}, 0500;
    }
    unless (-d $config{'PSAD_FIFO_DIR'}) {
        &logr("[+] Creating $config{'PSAD_FIFO_DIR'}\n");
        mkdir $config{'PSAD_FIFO_DIR'}, 0500;
    }

    ### change any existing psad module directory to allow anyone to import
    my $dir_tmp = $config{'PSAD_LIBS_DIR'};
    $dir_tmp =~ s|lib/|lib64/|;
    for my $dir ($config{'PSAD_LIBS_DIR'}, $dir_tmp) {
        if (-d $dir) {
            chmod 0755, $dir;
            unless ($no_rm_old_lib_dir) {
                &logr("[+] Removing $dir/ directory from previous " .
                    "psad installation.\n");
                rmtree $dir;
            }
        }
    }
    unless (-d $config{'PSAD_CONF_DIR'}) {
        &logr("[+] Creating $config{'PSAD_CONF_DIR'}\n");
        mkdir $config{'PSAD_CONF_DIR'}, 0500;
    }
    unless (-d $config{'CONF_ARCHIVE_DIR'}) {
        &logr("[+] Creating $config{'CONF_ARCHIVE_DIR'}\n");
        mkdir $config{'CONF_ARCHIVE_DIR'}, 0500;
    }
    unless (-e $config{'PSAD_FIFO_FILE'}) {
        &logr("[+] Creating named pipe $config{'PSAD_FIFO_FILE'}\n");
        unless (((system "$cmds{'mknod'} -m 600 " .
                "$config{'PSAD_FIFO_FILE'} p")>>8) == 0) {
            &logr("[*] Could not create the named pipe " .
                "\"$config{'PSAD_FIFO_FILE'}\"!\n" .
                "[*] psad requires this file to exist!  Aborting install.\n");
            die;
        }
        unless (-p $config{'PSAD_FIFO_FILE'}) {
            &logr("[*] Could not create the named pipe " .
                "\"$config{'PSAD_FIFO_FILE'}\"!\n" .
                "[*] psad requires this file to exist!  Aborting " .
                "install.\n");
            die;
        }
    }

    unless (-d $config{'PSAD_DIR'}) {
        &logr("[+] Creating $config{'PSAD_DIR'}\n");
        mkdir $config{'PSAD_DIR'}, 0500;
    }
    unless (-e $config{'FW_DATA_FILE'}) {
        &logr("[+] Creating $config{'FW_DATA_FILE'} file\n");
        open F, "> $config{'FW_DATA_FILE'}" or die "[*] Could not open ",
            "$config{'FW_DATA_FILE'}: $!";
        close F;
        chmod 0600, "$config{'FW_DATA_FILE'}";
        &perms_ownership("$config{'FW_DATA_FILE'}", 0600);
    }

    unless (-d $USRSBIN_DIR) {
        &logr("[+] Creating $USRSBIN_DIR\n");
        mkdir $USRSBIN_DIR,0755;
    }
    if (-d 'whois') {
        &logr("[+] Compiling Marco d'Itri's whois client\n");
        system "$cmds{'make'} -C whois";
        if (-e 'whois/whois') {
            ### if an old whois process is still around ("text file
            ### busy" error), then it is ok to not be able to copy
            ### the new whois binary into place; the old one should
            ### work fine.
            &logr("[+] Copying whois binary to $cmds{'whois'}\n");
            copy 'whois/whois', $cmds{'whois'};
            die "[*] Could not copy whois/whois -> $cmds{'whois'}: $!"
                unless -e $cmds{'whois'};
        } else {
            die "[*] Could not compile whois";
        }
    }
    &perms_ownership($cmds{'whois'}, 0755);
    print "\n\n";

    ### install perl modules
    unless ($skip_module_install) {
        for my $module (keys %required_perl_modules) {
            &install_perl_module($module);
        }
    }

    &logr("[+] Installing Snort-2.3.3 signatures in " .
        "$config{'SNORT_RULES_DIR'}\n");
    unless (-d $config{'SNORT_RULES_DIR'}) {
        mkdir $config{'SNORT_RULES_DIR'}, 0500
            or die "[*] Could not create $config{'SNORT_RULES_DIR'}: $!";
    }
    opendir D, 'snort_rules' or die "[*] Could not open ",
        "the snort_rules directory: $!";
    my @files = readdir D;
    closedir D;

    for my $file (@files) {
        next unless $file =~ /\.rules$/ or $file =~ /\.config$/;
        &logr("[+] Installing snort_rules/${file}\n");
        copy "snort_rules/${file}", "$config{'SNORT_RULES_DIR'}/${file}" or
            die "[*] Could not copy snort_rules/${file} -> ",
                "$config{'SNORT_RULES_DIR'}/${file}: $!";
        &perms_ownership("$config{'SNORT_RULES_DIR'}/${file}", 0600);
    }
    print "\n\n";

    &logr("[+] Compiling kmsgsd, and psadwatchd:\n");

    ### remove any previously compiled kmsgsd
    unlink 'kmsgsd' if -e 'kmsgsd';

    ### remove any previously compiled psadwatchd
    unlink 'psadwatchd' if -e 'psadwatchd';

    ### compile the C psad daemons
    system $cmds{'make'};
    &logr("[-] Could not compile kmsgsd.c.\n") unless (-e 'kmsgsd');
    &logr("[-] Could not compile psadwatchd.c.\n") unless (-e 'psadwatchd');

    ### install fwcheck_psad.pl
    print "\n\n";
    &logr("[+] Verifying compilation of fwcheck_psad.pl script:\n");
    unless (((system "$cmds{'perl'} -c fwcheck_psad.pl")>>8) == 0) {
        die "[*] fwcheck_psad.pl does not compile with \"perl -c\".  Download ",
            "the latest sources from:\n\nhttp://www.cipherdyne.org/\n";
    }

    ### make sure the psad (perl) daemon compiles.  The other three
    ### daemons have all been re-written in C.
    &logr("[+] Verifying compilation of psad perl daemon:\n");
    unless (((system "$cmds{'perl'} -c psad")>>8) == 0) {
        die "[*] psad does not compile with \"perl -c\".  Download the",
            " latest sources from:\n\nhttp://www.cipherdyne.org/\n";
    }

    ### install nf2csv
    &logr("[+] Verifying compilation of nf2csv script:\n");
    unless (((system "$cmds{'perl'} -c nf2csv")>>8) == 0) {
        die "[*] nf2csv does not compile with \"perl -c\".  Download ",
            "the latest sources from:\n\nhttp://www.cipherdyne.org/\n";
    }

    ### put the nf2csv script in place
    unlink '/usr/sbin/nf2csv' if -e '/usr/sbin/nf2csv';  ### old path
    &logr("[+] Copying nf2csv -> ${USRBIN_DIR}/nf2csv\n");
    unlink "${USRBIN_DIR}/nf2csv" if -e "${USRBIN_DIR}/nf2csv";
    copy 'nf2csv', "${USRBIN_DIR}/nf2csv" or die "[*] Could ",
        "not copy nf2csv -> ${USRBIN_DIR}/nf2csv: $!";
    &perms_ownership("${USRBIN_DIR}/nf2csv", 0755);

    ### put the fwcheck_psad.pl script in place
    &logr("[+] Copying fwcheck_psad.pl -> $cmds{'fwcheck_psad'}\n");
    unlink $cmds{'fwcheck_psad'} if -e $cmds{'fwcheck_psad'};
    copy 'fwcheck_psad.pl', $cmds{'fwcheck_psad'} or die "[*] Could ",
        "not copy fwcheck_psad.pl -> $cmds{'fwcheck_psad'}: $!";
    &perms_ownership($cmds{'fwcheck_psad'}, 0500);

    ### put the psad daemons in place
    &logr("[+] Copying psad -> ${USRSBIN_DIR}/psad\n");
    unlink "${USRSBIN_DIR}/psad" if -e "${USRSBIN_DIR}/psad";
    copy 'psad', "${USRSBIN_DIR}/psad" or die "[*] Could not copy ",
        "psad -> ${USRSBIN_DIR}/psad: $!";
    &perms_ownership("${USRSBIN_DIR}/psad", 0500);

    &logr("[+] Copying psadwatchd -> ${USRSBIN_DIR}/psadwatchd\n");
    unlink "${USRSBIN_DIR}/psadwatchd" if -e "${USRSBIN_DIR}/psadwatchd";
    copy 'psadwatchd', "${USRSBIN_DIR}/psadwatchd" or die "[*] Could not ",
        "copy psadwatchd -> ${USRSBIN_DIR}/psadwatchd: $!";
    &perms_ownership("${USRSBIN_DIR}/psadwatchd", 0500);

    &logr("[+] Copying kmsgsd -> ${USRSBIN_DIR}/kmsgsd\n");
    unlink "${USRSBIN_DIR}/kmsgsd" if -e "${USRSBIN_DIR}/kmsgsd";
    copy 'kmsgsd', "${USRSBIN_DIR}/kmsgsd" or die "[*] Could not copy ",
        "kmsgsd -> ${USRSBIN_DIR}/kmsgsd: $!";
    &perms_ownership("${USRSBIN_DIR}/kmsgsd", 0500);

    unless (-d $config{'PSAD_CONF_DIR'}) {
        &logr("[+] Creating $config{'PSAD_CONF_DIR'}\n");
        mkdir $config{'PSAD_CONF_DIR'},0500;
    }

    ### get syslog daemon (e.g. syslog, rsyslog syslog-ng, or metalog)
    my $syslog_str = &query_syslog();

    my $preserve_rv = 0;
    if (-e "$config{'PSAD_CONF_DIR'}/psad.conf") {
        $preserve_rv = &query_preserve_config();
    }

    ### the order of the config files is important (legacy FW_MSG_SEARCH
    ### vars in psad.conf).
    my $prod_file = "$config{'PSAD_CONF_DIR'}/psad.conf";
    if (-e $prod_file) {
        &archive($prod_file) unless $noarchive;
        if ($preserve_rv) {
            &preserve_config('psad.conf', $prod_file);
        } else {
            &logr("[+] Copying psad.conf -> $prod_file\n");
            copy 'psad.conf', $prod_file or die "[*] Could not ",
                "copy psad.conf -> $prod_file: $!";
        }
    } else {
        &logr("[+] Copying psad.conf -> $prod_file\n");
        copy 'psad.conf', $prod_file or die "[*] Could not copy ",
            "psad.conf -> $prod_file: $!";
    }

    if ($force_path_update or not $preserve_rv) {
        &update_command_paths($prod_file);
    }

    &perms_ownership($prod_file, 0600);

    ### install auto_dl, signatures, icmp_types, posf, and pf.os files
    for my $filename qw(signatures icmp_types
            posf auto_dl snort_rule_dl pf.os ip_options) {
        my $file = $config{$file_vars{$filename}};
        if (-e $file) {
            &archive($file) unless $noarchive;
            ### FIXME, need a real config preservation routine for these files.
            unless (&query_preserve_sigs_autodl($file)) {
                &logr("[+] Copying $filename -> $file\n");
                copy $filename, $file or die "[*] Could not ",
                    "copy $filename -> $file: $!";
                &perms_ownership($file, 0600);
            }
        } else {
            &logr("[+] Copying $filename -> $file\n");
            copy $filename, $file or die "[*] Could not ",
                "copy $filename -> $file: $!";
            &perms_ownership($file, 0600);
        }
    }

    ### archive and remove legacy config files
    for my $filename qw(kmsgsd.conf psadwatchd.conf alert.conf
            fw_search.conf) {
        my $path = "$config{'PSAD_CONF_DIR'}/$filename";
        if (-e $path) {
            &archive($path);
            unlink $path;
        }
    }
    &logr("\n");

    unless ($preserve_rv) {  ### we want to preserve the existing config

        ### get email address(es)
        my $email_str = &query_email();
        if ($email_str) {
            &put_string('EMAIL_ADDRESSES', $email_str,
                "$config{'PSAD_CONF_DIR'}/psad.conf");
        }

        ### Give the admin the opportunity to set the strings that are
        ### parsed out of iptables messages.  This is useful since the
        ### admin may have configured the firewall to use a logging prefix
        ### of "Audit" or something else other than the default string
        ### "DROP".
        my $fw_search_aref = &get_fw_search_strings();
        if ($fw_search_aref) {
            open F, "< $config{'PSAD_CONF_DIR'}/psad.conf"
                or die "[*] Could not open ",
                    "$config{'PSAD_CONF_DIR'}/psad.conf: $!";
            my @lines = <F>;
            close F;
            open T, "> $config{'PSAD_CONF_DIR'}/psad.conf.tmp"
                or die "[*] Could not open ",
                    "$config{'PSAD_CONF_DIR'}/psad.conf.tmp: $!";
            for my $line (@lines) {
                if ($line =~ /^\s*FW_MSG_SEARCH\s/) {
                    for my $fw_str (@$fw_search_aref) {
                        &logr(qq{[+] Setting FW_MSG_SEARCH to "$fw_str" } .
                            "in $config{'PSAD_CONF_DIR'}/psad.conf\n");
                        printf T "%-28s%s;\n", 'FW_MSG_SEARCH', $fw_str;
                    }
                } else {
                    print T $line unless $line =~ /^\s*FW_MSG_SEARCH\s/;
                }
            }
            close T;
            move "$config{'PSAD_CONF_DIR'}/psad.conf.tmp",
                "$config{'PSAD_CONF_DIR'}/psad.conf"
                or die "[*] Could not move ",
                "$config{'PSAD_CONF_DIR'}/psad.conf.tmp -> ",
                "$config{'PSAD_CONF_DIR'}/psad.conf: $!";
        }
        ### Give the admin the opportunity to set the HOME_NET variable.
        &set_home_net("$config{'PSAD_CONF_DIR'}/psad.conf");

        ### see if the admin would like to have psad send info to
        ### DShield
        if (&query_dshield()) {
            &put_string('ENABLE_DSHIELD_ALERTS', 'Y',
                "$config{'PSAD_CONF_DIR'}/psad.conf");
        }

        ### Set the hostname
        my $file = "$config{'PSAD_CONF_DIR'}/psad.conf";
        &logr("[+] Setting hostname to \"$HOSTNAME\" in $file\n");
        &set_hostname($file);
    }

    &put_string('SYSLOG_DAEMON', $syslog_str,
        "$config{'PSAD_CONF_DIR'}/psad.conf");

    if ($syslog_str ne 'ulogd') {
        my $restarted_syslog = 0;
        if ($syslog_str eq 'syslogd') {
            if (-e $syslog_conf) {
                &append_fifo_syslog($syslog_conf);
                if (((system "$cmds{'killall'} -HUP syslogd 2> /dev/null")>>8) == 0) {
                    &logr("[+] HUP signal sent to syslogd.\n");
                    $restarted_syslog = 1;
                }
            }
        } elsif ($syslog_str eq 'rsyslogd') {
            if (-e $syslog_conf) {
                &append_fifo_syslog($syslog_conf);
                if (((system "$cmds{'killall'} -HUP rsyslogd 2> /dev/null")>>8) == 0) {
                    &logr("[+] HUP signal sent to rsyslogd.\n");
                    $restarted_syslog = 1;
                }
            }

        } elsif ($syslog_str eq 'syslog-ng') {
            if (-e $syslog_conf) {
                &append_fifo_syslog_ng($syslog_conf);
                if (((system "$cmds{'killall'} -HUP syslog-ng 2> /dev/null")>>8) == 0) {
                    &logr("[+] HUP signal sent to syslog-ng.\n");
                    $restarted_syslog = 1;
                }
            }
        } elsif ($syslog_str eq 'metalog') {
            if (-e $syslog_conf) {
                &config_metalog($syslog_conf);
                &logr("[-] Metalog support is shaky in psad.  " .
                    "Use at your own risk.\n");
                ### don't send warning about not restarting metalog daemon
                $restarted_syslog = 1;
            }
        }

        unless ($restarted_syslog) {
            &logr("[-] Could not restart any syslog daemons.\n");
        }
    }

    if (-x $cmds{'iptables'} and not $skip_syslog_test) {
        &logr("[+] Found iptables. Testing syslog configuration:\n");
        ### make sure we actually see packets being logged by
        ### the firewall.
        if ($syslog_str ne 'ulogd') {
            if (&test_syslog_config($syslog_str)) {
                &logr("[+] Successful $syslog_str reconfiguration.\n\n");
            } else {
                if (&query_init_script_restart_syslog()) {

                    my $restarted = 0;
                    if ($syslog_str eq 'syslog-ng') {
                        if (-e "$init_dir/syslog-ng") {
                            system "$init_dir/syslog-ng restart";
                            $restarted = 1;
                        }
                    } elsif ($syslog_str eq 'rsyslogd') {
                        if (-e "$init_dir/sysklogd") {
                            system "$init_dir/sysklogd restart";
                            $restarted = 1;
                        } elsif (-e "$init_dir/syslog") {
                            system "$init_dir/syslog restart";
                            $restarted = 1;
                        }
                    } else {
                        if (-e "$init_dir/rsyslog") {
                            system "$init_dir/rsyslog restart";
                            $restarted = 1;
                        }
                    }
                    ### test syslog config again now that we
                    ### have restarted syslog via the init script
                    ### instead of relying on a HUP signal to
                    ### syslog
                    if ($restarted) {
                        if (&test_syslog_config($syslog_str)) {
                            &logr("[+] Successful $syslog_str reconfiguration.\n\n");
                        } else {
                            &logr("[-] Unsuccessful $syslog_str reconfiguration.\n");
                            &logr("    Consult the psad man page for the basic " .
                                "$syslog_str requirement to get psad to work.\n\n");
                        }
                    }
                } else {
                    &logr("[-] Ok, hoping that psad can get packet data anyway.\n");
                }
            }
        }
    }

    ### download signatures?
    &download_signatures() if &query_signatures();

    &install_manpage('psad.8');
    &install_manpage('psadwatchd.8');
    &install_manpage('kmsgsd.8');
    &install_manpage('nf2csv.1');

    my $init_file = '';
    if ($distro eq 'redhat') {
        $init_file = 'init-scripts/psad-init.redhat';
    } elsif ($distro eq 'fedora') {
        $init_file = 'init-scripts/psad-init.fedora';
    } elsif ($distro eq 'gentoo') {
        $init_file = 'init-scripts/psad-init.gentoo';
    } else {
        $init_file = 'init-scripts/psad-init.generic';
    }

    if ($init_dir) {
        &logr("[+] Copying $init_file -> ${init_dir}/$init_name\n");
        copy $init_file, "${init_dir}/$init_name" or die "[*] Could not copy ",
            "$init_file -> ${init_dir}/$init_name: $!";
        &perms_ownership("${init_dir}/$init_name", 0744);
        &enable_psad_at_boot($distro);
    }

    &logr("\n========================================================\n");
    if ($archived_old) {
        &logr("[+] Copies of your original configs have been made " .
            "in: $config{'CONF_ARCHIVE_DIR'}\n");
    }
    if ($preserve_rv) {
        &logr("\n[+] psad has been installed (with your original config merged).\n");
    } else {
        &logr("\n[+] psad has been installed.\n");
    }
    if ($init_dir) {
        &logr("\n[+] To start psad, run \"${init_dir}/psad start\"\n");
    } else {
        &logr("\n[+] To start psad, run ${USRSBIN_DIR}/psad\"\n");
    }
    return;
}

sub import_config() {
    open C, "< $psad_conf_file"
        or die "[*] Could not open $psad_conf_file: $!";
    while (<C>) {
        next if /^\s*#/;
        if (/^\s*(\S+)\s+(.*?)\;/) {
            my $varname = $1;
            my $val     = $2;
            if ($val =~ m|/.+| and $varname =~ /^\s*(\S+)Cmd$/) {
                ### found a command
                $cmds{$1} = $val;
            } else {
                $config{$varname} = $val;
            }
        }
    }
    close C;

    ### resolve internal vars within variable values
    &expand_vars();

    &required_vars();

    return;
}

sub expand_vars() {

    my $has_sub_var = 1;