File: kmsgsd.pl

package info (click to toggle)
psad 1.4.8-1
  • links: PTS
  • area: main
  • in suites: etch, etch-m68k
  • size: 4,756 kB
  • ctags: 1,878
  • sloc: perl: 28,425; ansic: 8,323; makefile: 1,875; sh: 287
file content (141 lines) | stat: -rwxr-xr-x 4,017 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
#!/usr/bin/perl -w
#
###########################################################################
#
# File: kmsgsd
#
# Purpose: kmsgsd separates iptables messages from all other
#          kernel messages.
#
# Strategy: read message from the /var/lib/psad/psadfifo named pipe and 
#           print any firewall related dop/reject/deny messages to
#           the psad data file "/var/log/psad/fwdata".
#
# Author: Michael Rash (mbr@cipherdyne.org)
#
# Credits:  (see the CREDITS file)
#
# Copyright (C) 1999-2006 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
#
###########################################################################
#
# $Id: kmsgsd.pl 1536 2006-05-02 03:06:18Z mbr $
#

use lib '/usr/lib/psad';
use Psad;
use POSIX 'setsid';
use Getopt::Long 'GetOptions';
use strict;

### establish the default path to the config file (can be
### over-ridden with the -c <file> command line option.
my $CONFIG_FILE = '/etc/psad/kmsgsd.conf';

### configuration hash
my %config;

### commands hash
my %cmds;

### flag used for HUP signal
my $hup_flag = 0;

### handle command line arguments
die " ** Specify the path to the psad.conf file with " .
    "\"-c <file>\".\n\n" unless (GetOptions (
    'config=s' => \$CONFIG_FILE
));

### import config
&import_config();

### make sure there is not another kmsgsd already running
&Psad::unique_pid($config{'KMSGSD_PID_FILE'});

### install HUP handler so config can be re-imported
$SIG{'HUP'}  = \&hup_sig;

my $pid = fork;
exit if $pid;
die " ** $0: Couldn't fork: $!" unless defined($pid);
POSIX::setsid() or die " ** $0: Can't start a new session: $!\n";

### write the pid to the pid file
&Psad::writepid($config{'KMSGSD_PID_FILE'});

### open the fwdata file
open LOG, ">> $config{'FW_DATA_FILE'}" or
    die "Could not open $config{'FW_DATA_FILE'}: $!\n";

#===================== main =======================
### main loop
for (;;) {
    open FIFO, "< $config{'PSAD_FIFO'}" or die "Can't open file : $!\n";
    my $service = <FIFO>;  ### don't chomp for better performance
    if (defined $service
        && ($service =~ /Packet\slog/ || $service =~ /IN.+?OUT/)
        && ($service =~ /$config{'FW_MSG_SEARCH'}/
        || $service =~ /$config{'SNORT_SID_STR'}/)) {
        ### log to the fwdata file
        my $old_fh = select LOG;
        $| = 1;
        print $service;
        select $old_fh;
    }
    if ($hup_flag) {
        ### clear the HUP flag and re-import the config
        $hup_flag = 0;
        &import_config();
        close FIFO;
        open FIFO, "< $config{'PSAD_FIFO'}" or
            die "Can't open file : $!\n";
        &Psad::psyslog('psad(kmsgsd)', 'received HUP signal, ' .
            're-importing kmsgsd.conf');
    }
}
### These statements don't get executed, but for completeness...
close LOG;
close FIFO;
exit 0;
#==================== end main =====================
sub import_config() {

    ### read in the configuration file
    &Psad::buildconf(\%config, \%cmds, $CONFIG_FILE);

    ### make sure the configuration is complete
    &required_vars();

    ### Check to make sure the commands specified in the config section
    ### are in the right place, and attempt to correct automatically if not.
    &Psad::check_commands(\%cmds);

    return;
}

sub required_vars() {
    my @required_vars = qw(
        KMSGSD_PID_FILE PSAD_FIFO FW_DATA_FILE
        FW_MSG_SEARCH SNORT_SID_STR
    );
    &Psad::defined_vars($CONFIG_FILE, \@required_vars, \%config);
    return;
}

sub hup_sig() {
    $hup_flag = 1;
    return;
}