config/suricata/convert-snort

   1 #!/usr/bin/perl
   2 ###############################################################################
   3 #                                                                             #
   4 # IPFire.org - A linux based firewall                                         #
   5 # Copyright (C) 2019 IPFire Development Team <info@ipfire.org>                #
   6 #                                                                             #
   7 # This program is free software: you can redistribute it and/or modify        #
   8 # it under the terms of the GNU General Public License as published by        #
   9 # the Free Software Foundation, either version 3 of the License, or           #
  10 # (at your option) any later version.                                         #
  11 #                                                                             #
  12 # This program is distributed in the hope that it will be useful,             #
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of              #
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               #
  15 # GNU General Public License for more details.                                #
  16 #                                                                             #
  17 # You should have received a copy of the GNU General Public License           #
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
  19 #                                                                             #
  20 ###############################################################################
  21
  22 use strict;
  23
  24 require '/var/ipfire/general-functions.pl';
  25 require "${General::swroot}/ids-functions.pl";
  26
  27 # Snort settings file, which contains the settings from the WUI.
  28 my $snort_settings_file = "${General::swroot}/snort/settings";
  29
  30 # Main snort config file.
  31 my $snort_config_file = "/etc/snort/snort.conf";
  32
  33 # Snort rules tarball.
  34 my $snort_rules_tarball = "/var/tmp/snortrules.tar.gz";
  35
  36 #
  37 ## Step 1: Setup directory and file layout, if not present and set correct
  38 ##         ownership. The converter runs as a privileged user, but the files
  39 ##         needs to be full access-able by the WUI user and group (nobody:nobody).
  40 #
  41
  42 # Check if the settings directory exists.
  43 unless (-d $IDS::settingsdir) {
  44         # Create the directory.
  45         mkdir($IDS::settingsdir);
  46 }
  47
  48 # Check if the rules directory exists.
  49 unless (-d $IDS::rulespath) {
  50         # Create the directory.
  51         mkdir($IDS::rulespath);
  52 }
  53
  54 # Create file layout, if not exists yet.
  55 &IDS::check_and_create_filelayout();
  56
  57 # Set correct ownership for settingsdir and rulespath.
  58 &IDS::set_ownership("$IDS::settingsdir");
  59 &IDS::set_ownership("$IDS::rulespath");
  60
  61 # Check if a snort settings file exists.
  62 unless( -f "$snort_settings_file") {
  63         print "$snort_settings_file not found - Nothing to do. Exiting!\n";
  64         exit(0);
  65 }
  66
  67 # Check if the snort settings file is empty.
  68 if (-z "$snort_settings_file") {
  69         print "$snort_settings_file is empty - Nothing to do. Exiting!\n";
  70         exit(0);
  71 }
  72
  73 #
  74 ## Step 2: Import snort settings and convert to the required format for the new IDS
  75 ##         (suricata).
  76 #
  77
  78 # Hash which contains the "old" snort settings.
  79 my %snortsettings;
  80
  81 # Hash which contains the IDS (suricata) settings.
  82 #
  83 # Add default value for MONITOR_TRAFFIC_ONLY which will be "on"
  84 # when migrating from snort to the new IDS.
  85 my %idssettings = (
  86         "MONITOR_TRAFFIC_ONLY" => "on",
  87 );
  88
  89 # Hash which contains the RULES settings.
  90 #
  91 # Set default value for UPDATE_INTERVAL to weekly.
  92 my %rulessettings = (
  93         "AUTOUPDATE_INTERVAL" => "weekly",
  94 );
  95
  96 # Get all available network zones.
  97 my @network_zones = &IDS::get_available_network_zones();
  98
  99 # Read-in snort settings file.
 100 &General::readhash("$snort_settings_file", \%snortsettings);
 101
 102 # Loop through the array of network zones.
 103 foreach my $zone (@network_zones) {
 104         # Convert current zone into upper case.
 105         my $zone_upper = uc($zone);
 106
 107         # Check if the current network zone is "red".
 108         if($zone eq "red") {
 109                 # Check if snort was enabled and enabled on red.
 110                 if ($snortsettings{"ENABLE_SNORT"} eq "on") {
 111                         # Enable the IDS.
 112                         $idssettings{"ENABLE_IDS"} = "on";
 113
 114                         # Enable the IDS on RED.
 115                         $idssettings{"ENABLE_IDS_$zone_upper"} = "on";
 116                 }
 117         } else {
 118                 # Check if snort was enabled on the current zone.
 119                 if ($snortsettings{"ENABLE_SNORT_$zone_upper"} eq "on") {
 120                         # Enable the IDS on this zone too.
 121                         $idssettings{"ENABLE_IDS_$zone_upper"} = "on";
 122                 }
 123         }
 124 }
 125
 126 # Grab the choosen ruleset from snort settings hash and store it in the rules
 127 # settings hash.
 128 $rulessettings{"RULES"} = $snortsettings{"RULES"};
 129
 130 # Check if an oinkcode has been provided.
 131 if($snortsettings{"OINKCODE"}) {
 132         # Take the oinkcode from snort settings hash and store it in the rules
 133         # settings hash.
 134         $rulessettings{"OINKCODE"} = $snortsettings{"OINKCODE"};
 135 }
 136
 137 #
 138 ## Step 3: Import guardian settings and whitelist if the addon is installed.
 139 #
 140
 141 # Pakfire meta file for owncloud.
 142 # (File exists when the addon is installed.)
 143 my $guardian_meta = "/opt/pakfire/db/installed/meta-guardian";
 144
 145 # Check if the guardian addon is installed.
 146 if (-f $guardian_meta) {
 147         # File which contains the taken setting for guardian.
 148         my $guardian_settings_file = "${General::swroot}/guardian/settings";
 149
 150         # File which contains the white-listed hosts.
 151         my $guardian_ignored_file = "${General::swroot}/guardian/ignored";
 152
 153         # Hash which will contain the settings of guardian.
 154         my %guardiansettings;
 155
 156         # Check if the settings file of guardian is empty.
 157         unless (-z $guardian_settings_file) {
 158                 # Read-in settings.
 159                 &General::readhash("$guardian_settings_file", \%guardiansettings);
 160         }
 161
 162         # Check if guardian is not configured to take actions on snort events.
 163         if ($guardiansettings{"GUARDIAN_MONITOR_SNORT"} eq "on") {
 164                 # Change the IDS into MONITOR_TRAFFIC_ONLY mode.
 165                 $idssettings{"MONITOR_TRAFFIC_ONLY"} = "off";
 166         }
 167
 168         # Check if guardian has any white-listed hosts configured.
 169         unless (-z $guardian_ignored_file) {
 170                 # Temporary hash to store the ignored hosts.
 171                 my %ignored_hosts;
 172
 173                 # Read-in white-listed hosts and store them in the hash.
 174                 &General::readhasharray($guardian_ignored_file, \%ignored_hosts);
 175
 176                 # Write-out the white-listed hosts for the IDS system.
 177                 &General::writehasharray($IDS::ignored_file, \%ignored_hosts);
 178
 179                 # Call subfunction to generate the file for white-listing the hosts.
 180                 &IDS::generate_ignored_file();
 181         }
 182
 183 }
 184
 185 #
 186 ## Step 4: Save IDS and rules settings.
 187 #
 188
 189 # Write IDS settings.
 190 &General::writehash("$IDS::ids_settings_file", \%idssettings);
 191
 192 # Write rules settings.
 193 &General::writehash("$IDS::rules_settings_file", \%rulessettings);
 194
 195 #
 196 ## Step 5: Generate and write the file to modify the ruleset.
 197 #
 198
 199 # Converters default is to only monitor the traffic, so set the IDS action to
 200 # "alert".
 201 my $IDS_action = "alert";
 202
 203 # Check if the traffic only should be monitored.
 204 if ($idssettings{"MONITOR_TRAFFIC_ONLY"} eq "off") {
 205         # Swith IDS action to alert only.
 206         $IDS_action = "drop";
 207 }
 208
 209 # Call subfunction and pass the desired IDS action.
 210 &IDS::write_modify_sids_file($IDS_action);
 211
 212 #
 213 ## Step 6: Move rulestarball to its new location.
 214 #
 215
 216 # Check if a rulestarball has been downloaded yet.
 217 if (-f $snort_rules_tarball) {
 218         # Load perl module which contains the move command.
 219         use File::Copy;
 220
 221         # Move the rulestarball to the new location.
 222         move($snort_rules_tarball, $IDS::rulestarball);
 223
 224         # Set correct ownership.
 225         &IDS::set_ownership("$IDS::rulestarball");
 226 }
 227
 228 #
 229 ## Step 7: Call oinkmaster to extract and setup the rules structures.
 230 #
 231
 232 # Check if a rulestarball is present.
 233 if (-f $IDS::rulestarball) {
 234         # Launch oinkmaster by calling the subfunction.
 235         &IDS::oinkmaster();
 236 }
 237
 238 #
 239 ## Step 8: Grab used ruleset files from snort config file and convert
 240 ##         them into the new format.
 241 #
 242
 243 # Check if the snort config file exists.
 244 unless (-f $snort_config_file) {
 245         print "$snort_config_file does not exist - Nothing to do. Exiting!\n";
 246         exit(0);
 247 }
 248
 249 # Array to store the enabled rules files.
 250 my @enabled_rule_files;
 251
 252 # Open snort config file.
 253 open(SNORTCONF, $snort_config_file) or die "Could not open $snort_config_file. $!\n";
 254
 255 # Loop through the file content.
 256 while (my $line = <SNORTCONF>) {
 257         # Skip comments.
 258         next if ($line =~ /\#/);
 259
 260         # Skip blank  lines.
 261         next if ($line =~ /^\s*$/);
 262
 263         # Remove newlines.
 264         chomp($line);
 265
 266         # Check for a line with .rules
 267         if ($line =~ /\.rules$/) {
 268                 # Parse out rule file name
 269                 my $rulefile = $line;
 270                 $rulefile =~ s/\$RULE_PATH\///i;
 271                 $rulefile =~ s/ ?include ?//i;
 272
 273                 # Add the enabled rulefile to the array of enabled rule files.
 274                 push(@enabled_rule_files, $rulefile);
 275         }
 276 }
 277
 278 # Close filehandle.
 279 close(SNORTCONF);
 280
 281 # Pass the array of enabled rule files to the subfunction and write the file.
 282 &IDS::write_used_rulefiles_file(@enabled_rule_files);
 283
 284 #
 285 ## Step 9: Generate file for the HOME Net.
 286 #
 287
 288 # Call subfunction to generate the file.
 289 &IDS::generate_home_net_file();
 290
 291 #
 292 ## Step 10: Setup automatic ruleset updates.
 293 #
 294
 295 # Check if a ruleset is configured.
 296 if($rulessettings{"RULES"}) {
 297         # Call suricatactrl and setup the periodic update mechanism.
 298         &IDS::call_suricatactrl("cron", $rulessettings{'AUTOUPDATE_INTERVAL'});
 299 }
 300
 301 #
 302 ## Step 11: Start the IDS if enabled.
 303 #
 304
 305 # Check if the IDS should be started.
 306 if($idssettings{"ENABLE_IDS"} eq "on") {
 307         # Call suricatactrl and launch the IDS.
 308         &IDS::call_suricatactrl("start");
 309 }