config/cfgroot/network-functions.pl

   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) 2014 IPFire Team <info@ipfire.org>.                        #
  21 #                                                                          #
  22 ############################################################################
  23
  24 package Network;
  25
  26 require "/var/ipfire/general-functions.pl";
  27
  28 use Socket;
  29
  30 my %PREFIX2NETMASK = (
  31         32 => "255.255.255.255",
  32         31 => "255.255.255.254",
  33         30 => "255.255.255.252",
  34         29 => "255.255.255.248",
  35         28 => "255.255.255.240",
  36         27 => "255.255.255.224",
  37         26 => "255.255.255.192",
  38         25 => "255.255.255.128",
  39         24 => "255.255.255.0",
  40         23 => "255.255.254.0",
  41         22 => "255.255.252.0",
  42         21 => "255.255.248.0",
  43         20 => "255.255.240.0",
  44         19 => "255.255.224.0",
  45         18 => "255.255.192.0",
  46         17 => "255.255.128.0",
  47         16 => "255.255.0.0",
  48         15 => "255.254.0.0",
  49         14 => "255.252.0.0",
  50         13 => "255.248.0.0",
  51         12 => "255.240.0.0",
  52         11 => "255.224.0.0",
  53         10 => "255.192.0.0",
  54          9 => "255.128.0.0",
  55          8 => "255.0.0.0",
  56          7 => "254.0.0.0",
  57          6 => "252.0.0.0",
  58          5 => "248.0.0.0",
  59          4 => "240.0.0.0",
  60          3 => "224.0.0.0",
  61          2 => "192.0.0.0",
  62          1 => "128.0.0.0",
  63          0 => "0.0.0.0"
  64 );
  65
  66 my %NETMASK2PREFIX = reverse(%PREFIX2NETMASK);
  67
  68 # Takes an IP address in dotted decimal notation and
  69 # returns a 32 bit integer representing that IP addresss.
  70 # Will return undef for invalid inputs.
  71 sub ip2bin($) {
  72         my $address = shift;
  73
  74         # This function returns undef for undefined input.
  75         if (!defined $address) {
  76                 return undef;
  77         }
  78
  79         my $address_bin = &Socket::inet_pton(AF_INET, $address);
  80         if ($address_bin) {
  81                 $address_bin = unpack('N', $address_bin);
  82         }
  83
  84         return $address_bin;
  85 }
  86
  87 # Does the reverse of ip2bin().
  88 # Will return undef for invalid inputs.
  89 sub bin2ip($) {
  90         my $address_bin = shift;
  91
  92         # This function returns undef for undefined input.
  93         if (!defined $address_bin) {
  94                 return undef;
  95         }
  96
  97         my $address = pack('N', $address_bin);
  98         if ($address) {
  99                 $address = &Socket::inet_ntop(AF_INET, $address);
 100         }
 101
 102         return $address;
 103 }
 104
 105 # Takes a network in either a.b.c.d/a.b.c.d or a.b.c.d/e notation
 106 # and will return an 32 bit integer representing the start
 107 # address and an other one representing the network mask.
 108 sub network2bin($) {
 109         my $network = shift;
 110
 111         my ($address, $netmask) = split(/\//, $network, 2);
 112
 113         if (&check_prefix($netmask)) {
 114                 $netmask = &convert_prefix2netmask($netmask);
 115         }
 116
 117         my $address_bin = &ip2bin($address);
 118         my $netmask_bin = &ip2bin($netmask);
 119
 120         my $network_start = $address_bin & $netmask_bin;
 121
 122         return ($network_start, $netmask_bin);
 123 }
 124
 125 # Returns True for all valid IP addresses
 126 sub check_ip_address($) {
 127         my $address = shift;
 128
 129         # Normalise the IP address and compare the result with
 130         # the input - which should obviously the same.
 131         my $normalised_address = &_normalise_ip_address($address);
 132
 133         return ((defined $normalised_address) && ($address eq $normalised_address));
 134 }
 135
 136 # Returns True for all valid prefixes.
 137 sub check_prefix($) {
 138         my $prefix = shift;
 139
 140         return (exists $PREFIX2NETMASK{$prefix});
 141 }
 142
 143 # Returns True for all valid subnet masks.
 144 sub check_netmask($) {
 145         my $netmask = shift;
 146
 147         return (exists $NETMASK2PREFIX{$netmask});
 148 }
 149
 150 # Returns True for all valid inputs like a.b.c.d/a.b.c.d.
 151 sub check_ip_address_and_netmask($$) {
 152         my $network = shift;
 153
 154         my ($address, $netmask) = split(/\//, $network, 2);
 155
 156         # Check if the IP address is fine.
 157         #
 158         my $result = &check_ip_address($address);
 159         unless ($result) {
 160                 return $result;
 161         }
 162
 163         return &check_netmask($netmask);
 164 }
 165
 166 # Returns True for all valid subnets like a.b.c.d/e or a.b.c.d/a.b.c.d
 167 sub check_subnet($) {
 168         my $subnet = shift;
 169
 170         my ($address, $network) = split(/\//, $subnet, 2);
 171
 172         # Check if the IP address is fine.
 173         my $result = &check_ip_address($address);
 174         unless ($result) {
 175                 return $result;
 176         }
 177
 178         return &check_prefix($network) || &check_netmask($network);
 179 }
 180
 181 # For internal use only. Will take an IP address and
 182 # return it in a normalised style. Like 8.8.8.010 -> 8.8.8.8.
 183 sub _normalise_ip_address($) {
 184         my $address = shift;
 185
 186         my $address_bin = &ip2bin($address);
 187         if (!defined $address_bin) {
 188                 return undef;
 189         }
 190
 191         return &bin2ip($address_bin);
 192 }
 193
 194 # Returns the prefix for the given subnet mask.
 195 sub convert_netmask2prefix($) {
 196         my $netmask = shift;
 197
 198         if (exists $NETMASK2PREFIX{$netmask}) {
 199                 return $NETMASK2PREFIX{$netmask};
 200         }
 201
 202         return undef;
 203 }
 204
 205 # Returns the subnet mask for the given prefix.
 206 sub convert_prefix2netmask($) {
 207         my $prefix = shift;
 208
 209         if (exists $PREFIX2NETMASK{$prefix}) {
 210                 return $PREFIX2NETMASK{$prefix};
 211         }
 212
 213         return undef;
 214 }
 215
 216 # Takes an IP address and an offset and
 217 # will return the offset'th IP address.
 218 sub find_next_ip_address($$) {
 219         my $address = shift;
 220         my $offset = shift;
 221
 222         my $address_bin = &ip2bin($address);
 223         $address_bin += $offset;
 224
 225         return &bin2ip($address_bin);
 226 }
 227
 228 # Returns the network address of the given network.
 229 sub get_netaddress($) {
 230         my $network = shift;
 231         my ($network_bin, $netmask_bin) = &network2bin($network);
 232
 233         if (defined $network_bin) {
 234                 return &bin2ip($network_bin);
 235         }
 236
 237         return undef;
 238 }
 239
 240 # Returns the broadcast of the given network.
 241 sub get_broadcast($) {
 242         my $network = shift;
 243         my ($network_bin, $netmask_bin) = &network2bin($network);
 244
 245         return &bin2ip($network_bin ^ ~$netmask_bin);
 246 }
 247
 248 # Returns True if $address is in $network.
 249 sub ip_address_in_network($$) {
 250         my $address = shift;
 251         my $network = shift;
 252
 253         my $address_bin = &ip2bin($address);
 254         return undef unless (defined $address_bin);
 255
 256         my ($network_bin, $netmask_bin) = &network2bin($network);
 257
 258         # Find end address
 259         my $broadcast_bin = $network_bin ^ ~$netmask_bin;
 260
 261         return (($address_bin ge $network_bin) && ($address_bin le $broadcast_bin));
 262 }
 263
 264 sub setup_upstream_proxy() {
 265         my %proxysettings = ();
 266         &General::readhash("${General::swroot}/proxy/settings", \%proxysettings);
 267
 268         if ($proxysettings{'UPSTREAM_PROXY'}) {
 269                 my $credentials = "";
 270
 271                 if ($proxysettings{'UPSTREAM_USER'}) {
 272                         $credentials = $proxysettings{'UPSTREAM_USER'};
 273
 274                         if ($proxysettings{'UPSTREAM_PASSWORD'}) {
 275                                 $credentials .= ":" . $proxysettings{'UPSTREAM_PASSWORD'};
 276                         }
 277
 278                         $credentials .= "@";
 279                 }
 280
 281                 my $proxy = "http://" . $credentials . $proxysettings{'UPSTREAM_PROXY'};
 282
 283                 $ENV{'http_proxy'} = $proxy;
 284                 $ENV{'https_proxy'} = $proxy;
 285                 $ENV{'ftp_proxy'} = $proxy;
 286         }
 287 }
 288
 289 1;
 290
 291 # Remove the next line to enable the testsuite
 292 __END__
 293
 294 sub assert($) {
 295         my $ret = shift;
 296
 297         if ($ret) {
 298                 return;
 299         }
 300
 301         print "ASSERTION ERROR";
 302         exit(1);
 303 }
 304
 305 sub testsuite() {
 306         my $result;
 307
 308         my $address1 = &ip2bin("8.8.8.8");
 309         assert($address1 == 134744072);
 310
 311         my $address2 = &bin2ip($address1);
 312         assert($address2 eq "8.8.8.8");
 313
 314         # Check if valid IP addresses are correctly recognised.
 315         foreach my $address ("1.2.3.4", "192.168.180.1", "127.0.0.1") {
 316                 if (!&check_ip_address($address)) {
 317                         print "$address is not correctly recognised as a valid IP address!\n";
 318                         exit 1;
 319                 };
 320         }
 321
 322         # Check if invalid IP addresses are correctly found.
 323         foreach my $address ("456.2.3.4", "192.768.180.1", "127.1", "1", "a.b.c.d", "1.2.3.4.5", "1.2.3.4/12") {
 324                 if (&check_ip_address($address)) {
 325                         print "$address is recognised as a valid IP address!\n";
 326                         exit 1;
 327                 };
 328         }
 329
 330         $result = &check_ip_address_and_netmask("192.168.180.0/255.255.255.0");
 331         assert($result);
 332
 333         $result = &convert_netmask2prefix("255.255.254.0");
 334         assert($result == 23);
 335
 336         $result = &convert_prefix2netmask(8);
 337         assert($result eq "255.0.0.0");
 338
 339         $result = &find_next_ip_address("1.2.3.4", 2);
 340         assert($result eq "1.2.3.6");
 341
 342         $result = &ip_address_in_network("10.0.1.4", "10.0.0.0/8");
 343         assert($result);
 344
 345         return 0;
 346 }
 347
 348 &testsuite();