[ipfire-2.x.git] / config / cfgroot / ids-functions.pl

#!/usr/bin/perl -w
############################################################################
#                                                                          #
# This file is part of the IPFire Firewall.                                #
#                                                                          #
# IPFire is free software; you can redistribute it and/or modify           #
# it under the terms of the GNU General Public License as published by     #
# the Free Software Foundation; either version 2 of the License, or        #
# (at your option) any later version.                                      #
#                                                                          #
# IPFire 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 IPFire; if not, write to the Free Software                    #
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA #
#                                                                          #
# Copyright (C) 2018 IPFire Team <info@ipfire.org>.                        #
#                                                                          #
############################################################################

package IDS;

require '/var/ipfire/general-functions.pl';
require "${General::swroot}/lang.pl";

# Location where all config and settings files are stored.
our $settingsdir = "${General::swroot}/snort";

# Location and name of the tarball which contains the ruleset.
our $rulestarball = "/var/tmp/snortrules.tar.gz";

# File to store any errors, which also will be read and displayed by the wui.
our $storederrorfile = "/tmp/ids_storederror";

# Location where the rulefiles are stored.
our $rulespath = "/etc/snort/rules";

#
## Function for checking if at least 300MB of free disk space are available
## on the "/var" partition.
#
sub checkdiskspace () {
	# Call diskfree to gather the free disk space of /var.
	my @df = `/bin/df -B M /var`;

	# Loop through the output.
	foreach my $line (@df) {
		# Ignore header line.
		next if $line =~ m/^Filesystem/;

		# Search for a line with the device information.
		if ($line =~ m/dev/ ) {
			# Split the line into single pieces.
			my @values = split(' ', $line);
			my ($filesystem, $blocks, $used, $available, $used_perenctage, $mounted_on) = @values;

			# Check if the available disk space is more than 300MB.
			if ($available < 300) {
				# If there is not enough space, print out an error message.
				my $errormessage = "$Lang::tr{'not enough disk space'} < 300MB, /var $available MB";

				# Exit function and return the error message.
				return $errormessage;
			}
		}
	}

	# Everything okay, return nothing.
	return;
}

#
## This function is responsible for downloading the configured snort ruleset.
##
## * At first it obtains from the stored snortsettings which ruleset should be downloaded.
## * The next step is to get the download locations for all available rulesets.
## * After that, the function will check if an upstream proxy should be used and grab the settings.
## * The last step will be to generate the final download url, by obtaining the URL for the desired
##   ruleset, add the settings for the upstream proxy and final grab the rules tarball from the server.
#
sub downloadruleset {
	# Get snort settings.
	my %snortsettings=();
	&General::readhash("$settingsdir/settings", \%snortsettings);

	# Get all available ruleset locations.
	my %rulesetsources=();
	&General::readhash("$settingsdir/ruleset-sources.list", \%rulesetsources);

	# Read proxysettings.
	my %proxysettings=();
	&General::readhash("${General::swroot}/proxy/settings", \%proxysettings);

	# Load required perl module to handle the download.
	use LWP::UserAgent;

	# Init the download module.
	my $downloader = LWP::UserAgent->new;

	# Set timeout to 10 seconds.
	$downloader->timeout(10);

	# Check if an upstream proxy is configured.
	if ($proxysettings{'UPSTREAM_PROXY'}) {
		my ($peer, $peerport) = (/^(?:[a-zA-Z ]+\:\/\/)?(?:[A-Za-z0-9\_\.\-]*?(?:\:[A-Za-z0-9\_\.\-]*?)?\@)?([a-zA-Z0-9\.\_\-]*?)(?:\:([0-9]{1,5}))?(?:\/.*?)?$/);
		my $proxy_url;

		# Check if we got a peer.
		if ($peer) {
			$proxy_url = "http://";

			# Check if the proxy requires authentication.
			if (($proxysettings{'UPSTREAM_USER'}) && ($proxysettings{'UPSTREAM_PASSWORD'})) {
				$proxy_url .= "$proxysettings{'UPSTREAM_USER'}\:$proxysettings{'UPSTREAM_PASSWORD'}\@";
			}

			# Add proxy server address and port.
			$proxy_url .= "$peer\:$peerport";
		} else {
			# Break and return error message.
			return "$Lang::tr{'could not download latest updates'}";
		}

		# Setup proxy settings.
		$downloader->proxy('http', $proxy_url);
	}

	# Grab the right url based on the configured vendor.
	my $url = $rulesetsources{$snortsettings{'RULES'}};

	# Check if the vendor requires an oinkcode and add it if needed.
	$url =~ s/\<oinkcode\>/$snortsettings{'OINKCODE'}/g;

	# Abort if no url could be determined for the vendor.
	unless ($url) {
		# Abort and return errormessage.
		return "$Lang::tr{'could not download latest updates'}";
	}

	# Pass the requested url to the downloader.
	my $request = HTTP::Request->new(GET => $url);

	# Perform the request and save the output into the "$rulestarball" file.
	my $response = $downloader->request($request, $rulestarball);

	# Check if there was any error.
	unless ($response->is_success) {
		# Return error message.
		return "$response->status_line";
	}

	# If we got here, everything worked fine. Return nothing.
	return;
}

#
## A tiny wrapper function to call the oinkmaster script.
#
sub oinkmaster () {
	# Load perl module to talk to the kernel syslog.
	use Sys::Syslog qw(:DEFAULT setlogsock);

	# Establish the connection to the syslog service.
	openlog('oinkmaster', 'cons,pid', 'user');

	# Call oinkmaster to generate ruleset.
	open(OINKMASTER, "/usr/local/bin/oinkmaster.pl -v -s -u file://$rulestarball -C $settingsdir/oinkmaster.conf -o $rulespath|");

	# Log output of oinkmaster to syslog.
	while(<OINKMASTER>) {
		# The syslog function works best with an array based input,
		# so generate one before passing the message details to syslog.
		my @syslog = ("INFO", "$_");

		# Send the log message.
		syslog(@syslog);
	}

	# Close the pipe to oinkmaster process.
	close(OINKMASTER);

	# Close the log handle.
	closelog();
}

#
## Function to do all the logging stuff if the downloading or updating of the ruleset fails.
#
sub log_error ($) {
	my ($error) = @_;

	# Remove any newline.
	chomp($error);

	# Call private function to log the error message to syslog.
	&_log_to_syslog($error);

	# Call private function to write/store the error message in the storederrorfile.
	&_store_error_message($error);
}

#
## Function to log a given error message to the kernel syslog.
#
sub _log_to_syslog ($) {
	my ($message) = @_;

	# Load perl module to talk to the kernel syslog.
	use Sys::Syslog qw(:DEFAULT setlogsock);

	# The syslog function works best with an array based input,
	# so generate one before passing the message details to syslog.
	my @syslog = ("ERR", "<ERROR> $message");

	# Establish the connection to the syslog service.
	openlog('oinkmaster', 'cons,pid', 'user');

	# Send the log message.
	syslog(@syslog);

	# Close the log handle.
	closelog();
}

#
## Private function to write a given error message to the storederror file.
#
sub _store_error_message ($) {
        my ($message) = @_;

	# Remove any newline.
	chomp($message);

        # Open file for writing.
        open (ERRORFILE, ">$storederrorfile") or die "Could not write to $storederrorfile. $!\n";

        # Write error to file.
        print ERRORFILE "$message\n";

        # Close file.
        close (ERRORFILE);
}

1;
Commit	Line	Data
8dcebe53 SS	1	#!/usr/bin/perl -w
	2	############################################################################
	3	# #
	4	# This file is part of the IPFire Firewall. #
	5	# #
	6	# IPFire is free software; you can redistribute it and/or modify #
	7	# it under the terms of the GNU General Public License as published by #
	8	# the Free Software Foundation; either version 2 of the License, or #
	9	# (at your option) any later version. #
	10	# #
	11	# IPFire is distributed in the hope that it will be useful, #
	12	# but WITHOUT ANY WARRANTY; without even the implied warranty of #
	13	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
	14	# GNU General Public License for more details. #
	15	# #
	16	# You should have received a copy of the GNU General Public License #
	17	# along with IPFire; if not, write to the Free Software #
	18	# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA #
	19	# #
	20	# Copyright (C) 2018 IPFire Team <info@ipfire.org>. #
	21	# #
	22	############################################################################
	23
	24	package IDS;
	25
	26	require '/var/ipfire/general-functions.pl';
	27	require "${General::swroot}/lang.pl";
	28
02844177 SS	29	# Location where all config and settings files are stored.
	30	our $settingsdir = "${General::swroot}/snort";
	31
eea2670b	32	# Location and name of the tarball which contains the ruleset.
77910792	33	our $rulestarball = "/var/tmp/snortrules.tar.gz";
eea2670b	34
3983aebd	35	# File to store any errors, which also will be read and displayed by the wui.
77910792	36	our $storederrorfile = "/tmp/ids_storederror";
3983aebd	37
298ef5ba SS	38	# Location where the rulefiles are stored.
	39	our $rulespath = "/etc/snort/rules";
	40
8dcebe53 SS	41	#
	42	## Function for checking if at least 300MB of free disk space are available
	43	## on the "/var" partition.
	44	#
	45	sub checkdiskspace () {
	46	# Call diskfree to gather the free disk space of /var.
	47	my @df = `/bin/df -B M /var`;
	48
	49	# Loop through the output.
	50	foreach my $line (@df) {
	51	# Ignore header line.
	52	next if $line =~ m/^Filesystem/;
	53
	54	# Search for a line with the device information.
	55	if ($line =~ m/dev/ ) {
	56	# Split the line into single pieces.
	57	my @values = split(' ', $line);
	58	my ($filesystem, $blocks, $used, $available, $used_perenctage, $mounted_on) = @values;
	59
	60	# Check if the available disk space is more than 300MB.
	61	if ($available < 300) {
	62	# If there is not enough space, print out an error message.
	63	my $errormessage = "$Lang::tr{'not enough disk space'} < 300MB, /var $available MB";
	64
	65	# Exit function and return the error message.
	66	return $errormessage;
	67	}
	68	}
	69	}
	70
	71	# Everything okay, return nothing.
	72	return;
	73	}
	74
eea2670b SS	75	#
	76	## This function is responsible for downloading the configured snort ruleset.
	77	##
	78	## * At first it obtains from the stored snortsettings which ruleset should be downloaded.
	79	## * The next step is to get the download locations for all available rulesets.
	80	## * After that, the function will check if an upstream proxy should be used and grab the settings.
	81	## * The last step will be to generate the final download url, by obtaining the URL for the desired
	82	## ruleset, add the settings for the upstream proxy and final grab the rules tarball from the server.
	83	#
	84	sub downloadruleset {
	85	# Get snort settings.
	86	my %snortsettings=();
02844177	87	&General::readhash("$settingsdir/settings", \%snortsettings);
eea2670b SS	88
	89	# Get all available ruleset locations.
	90	my %rulesetsources=();
02844177	91	&General::readhash("$settingsdir/ruleset-sources.list", \%rulesetsources);
eea2670b SS	92
	93	# Read proxysettings.
	94	my %proxysettings=();
	95	&General::readhash("${General::swroot}/proxy/settings", \%proxysettings);
	96
	97	# Load required perl module to handle the download.
	98	use LWP::UserAgent;
	99
	100	# Init the download module.
	101	my $downloader = LWP::UserAgent->new;
	102
	103	# Set timeout to 10 seconds.
	104	$downloader->timeout(10);
	105
	106	# Check if an upstream proxy is configured.
	107	if ($proxysettings{'UPSTREAM_PROXY'}) {
	108	my ($peer, $peerport) = (/^(?:[a-zA-Z ]+\:\/\/)?(?:[A-Za-z0-9\_\.\-]?(?:\:[A-Za-z0-9\_\.\-]?)?\@)?([a-zA-Z0-9\.\_\-]?)(?:\:([0-9]{1,5}))?(?:\/.?)?$/);
	109	my $proxy_url;
	110
	111	# Check if we got a peer.
	112	if ($peer) {
	113	$proxy_url = "http://";
	114
	115	# Check if the proxy requires authentication.
	116	if (($proxysettings{'UPSTREAM_USER'}) && ($proxysettings{'UPSTREAM_PASSWORD'})) {
	117	$proxy_url .= "$proxysettings{'UPSTREAM_USER'}\:$proxysettings{'UPSTREAM_PASSWORD'}\@";
	118	}
	119
	120	# Add proxy server address and port.
	121	$proxy_url .= "$peer\:$peerport";
	122	} else {
	123	# Break and return error message.
	124	return "$Lang::tr{'could not download latest updates'}";
	125	}
	126
	127	# Setup proxy settings.
	128	$downloader->proxy('http', $proxy_url);
	129	}
	130
	131	# Grab the right url based on the configured vendor.
	132	my $url = $rulesetsources{$snortsettings{'RULES'}};
	133
	134	# Check if the vendor requires an oinkcode and add it if needed.
	135	$url =~ s/\<oinkcode\>/$snortsettings{'OINKCODE'}/g;
	136
	137	# Abort if no url could be determined for the vendor.
	138	unless ($url) {
	139	# Abort and return errormessage.
	140	return "$Lang::tr{'could not download latest updates'}";
	141	}
	142
	143	# Pass the requested url to the downloader.
	144	my $request = HTTP::Request->new(GET => $url);
	145
	146	# Perform the request and save the output into the "$rulestarball" file.
	147	my $response = $downloader->request($request, $rulestarball);
	148
	149	# Check if there was any error.
	150	unless ($response->is_success) {
	151	# Return error message.
	152	return "$response->status_line";
	153	}
	154
	155	# If we got here, everything worked fine. Return nothing.
156	return;
157	}
8dcebe53	158
25f5cb0d SS	159	#
	160	## A tiny wrapper function to call the oinkmaster script.
	161	#
	162	sub oinkmaster () {
0e40e1e7 SS	163	# Load perl module to talk to the kernel syslog.
	164	use Sys::Syslog qw(:DEFAULT setlogsock);
	165
	166	# Establish the connection to the syslog service.
	167	openlog('oinkmaster', 'cons,pid', 'user');
	168
25f5cb0d	169	# Call oinkmaster to generate ruleset.
02844177	170	open(OINKMASTER, "/usr/local/bin/oinkmaster.pl -v -s -u file://$rulestarball -C $settingsdir/oinkmaster.conf -o $rulespath\|");
0e40e1e7 SS	171
	172	# Log output of oinkmaster to syslog.
	173	while(<OINKMASTER>) {
	174	# The syslog function works best with an array based input,
	175	# so generate one before passing the message details to syslog.
	176	my @syslog = ("INFO", "$_");
	177
	178	# Send the log message.
	179	syslog(@syslog);
	180	}
	181
	182	# Close the pipe to oinkmaster process.
	183	close(OINKMASTER);
	184
	185	# Close the log handle.
	186	closelog();
25f5cb0d SS	187	}
25f5cb0d SS	188
3983aebd SS	189	#
	190	## Function to do all the logging stuff if the downloading or updating of the ruleset fails.
	191	#
	192	sub log_error ($) {
	193	my ($error) = @_;
	194
	195	# Remove any newline.
	196	chomp($error);
	197
eb5592c1 SS	198	# Call private function to log the error message to syslog.
	199	&_log_to_syslog($error);
	200
3983aebd SS	201	# Call private function to write/store the error message in the storederrorfile.
	202	&_store_error_message($error);
	203	}
	204
eb5592c1 SS	205	#
	206	## Function to log a given error message to the kernel syslog.
	207	#
	208	sub _log_to_syslog ($) {
	209	my ($message) = @_;
	210
	211	# Load perl module to talk to the kernel syslog.
	212	use Sys::Syslog qw(:DEFAULT setlogsock);
	213
	214	# The syslog function works best with an array based input,
	215	# so generate one before passing the message details to syslog.
	216	my @syslog = ("ERR", "<ERROR> $message");
	217
	218	# Establish the connection to the syslog service.
	219	openlog('oinkmaster', 'cons,pid', 'user');
	220
	221	# Send the log message.
	222	syslog(@syslog);
	223
	224	# Close the log handle.
	225	closelog();
	226	}
	227
3983aebd SS	228	#
	229	## Private function to write a given error message to the storederror file.
	230	#
	231	sub _store_error_message ($) {
	232	my ($message) = @_;
	233
	234	# Remove any newline.
	235	chomp($message);
	236
	237	# Open file for writing.
	238	open (ERRORFILE, ">$storederrorfile") or die "Could not write to $storederrorfile. $!\n";
	239
	240	# Write error to file.
	241	print ERRORFILE "$message\n";
	242
	243	# Close file.
	244	close (ERRORFILE);
	245	}
	246
8dcebe53	247	1;