.
*/
// **************************************************************************************************************
//
// The purpose of this script is to dynamically add hosts to your local network. My local network is locked
// down such that known hosts are allocated an IP address in 192.168.0/24 and unknown hosts are allocated an
// IP address in 192.168.1/24. These unknown hosts are severely locked down in what they can do. My Web server
// and DHCP server are one and the same, to make life easy. This script will programmatically add clients to
// the hosts and dhcpd.conf file, making them known hosts. Interestingly, if a client on the local network
// accesses this script, their MAC address should be pre-populated to eliminate the most annoying step in the
// process. Consequently, it would be wise to require some kind of authentication to access this script. This is
// the type of thing that public "hot spots" do, where they allow anyone to connect to the local network but you
// have to add yourself to the known hosts pool before you can do anything useful.
//
// I like to keep my wired clients in the 192.168.0.2-100 range and my wireless clients in the 192.168.0.101-254
// range for organization purposes (it also makes it easier to filter traffic). Thus, this script expects the
// hosts and dhcpd.conf files to have a specific format (the file comments and spacing are the important parts!).
// hosts:
// # Wired Hosts
// 192.168.0.2 wired_host1
// 192.168.0.3 wired_host2
//
// # Wireless Hosts
// 192.168.0.101 wireless_host1
// 192.168.0.102 wireless_host2
//
// dhcpd.conf:
// ...
// host wired_host1
// {
// hardware ethernet: 00:11:22:33:44:55;
// fixed-address: 192.168.0.2;
// }
//
// host wired_host2
// {
// hardware ethernet: 66:77:88:99:AA:BB;
// fixed-address: 192.168.0.3;
// }
//
// This script could easily be manipulated to accomodate your own format preferences or do-away with the wired/
// wireless segregation.
//
// **************************************************************************************************************
// **************************************************************************************************************
//
// Apache will need to be able to sudo your dhcpd init script, and write to dhcpd.conf and the hosts file:
// visudo: www-data ALL=NOPASSWD: /etc/init.d/dhcp3-server
//
// **************************************************************************************************************
$dhcpd_conf_path = "/etc/dhcp3/dhcpd.conf";
$dhcpd_init_path = "/etc/init.d/dhcp3-server";
$hosts_path = "/etc/hosts";
$class_c = "192.168.0.";
$wireless_start = 100;
// Define more connection lengths here if desired
$conn_lengths = array("1 days" => "1 Day", "1 weeks" => "1 Week", "1 month" => "1 Month", "never" => "Never");
// Security question/answer for authentication so not just anyone can add themselves to your network
$question = "What is the name of the network owner's daughter?";
$answer = "Aubrey";
print "\n";
print "\n";
print "Add Host\n";
print "\n";
print "\n";
print "\n";
if ($_GET["submit"] == "true")
{
if (stripos($_POST["answer"], $answer) !== false)
{
$name = $_POST["name"];
$mac = $_POST["mac"];
$conn_length = $_POST["conn_length"];
$_POST["wireless"] == "on" ? $wireless = true : $wireless = false;
$dhcpd = $orig_dhcpd = file($dhcpd_conf_path);
$divider = array_search("# Wireless Hosts\n", $dhcpd) - 1;
foreach ($dhcpd as $line)
{
if (preg_match("/range $class_c(\d+) $class_c(\d+);/", $line, $match))
{
$min_last_octet = (int)$match[1];
$max_last_octet = (int)$match[2];
break;
}
}
if ($wireless)
{
$last_octet = $wireless_start;
$start = $divider;
$max = count($dhcpd);
}
else
{
$last_octet = $min_last_octet;
$start = 0;
$max = $divider;
}
for ($i = $start; $i < $max; $i++)
if (preg_match("/fixed-address $class_c(\d+);/", $dhcpd[$i], $match))
$last_octet = max($last_octet, (int)$match[1]);
$last_octet++;
$ip = $class_c . $last_octet;
if ($last_octet > $max_last_octet)
die("IP $ip not in range!");
if (!$wireless && $last_octet > $wireless_start)
print "Notice: wired IP $ip falls in wireless range.\n\n";
if ($wireless)
$dhcpd[] = "\nhost $name\n{\n\thardware ethernet $mac;\n\tfixed-address $ip;\n}\n";
else
{
for ($i = count($dhcpd)-1; $i >= $divider; $i--)
$dhcpd[$i+1] = $dhcpd[$i];
$dhcpd[$divider] = "\nhost $name\n{\n\thardware ethernet $mac;\n\tfixed-address $ip;\n}\n";
}
//die(print_r($dhcpd));
file_put_contents($dhcpd_conf_path, $dhcpd);
passthru("sudo $dhcpd_init_path restart", $ret);
// Restarting dhcpd failed, probably malformed conf file
if ($ret != 0)
{
// Revert back to previous data, which presumably was working before
file_put_contents($dhcpd_conf_path, $orig_dhcpd);
passthru("sudo $dhcpd_init_path restart", $ret);
die('DHCPD restart failed!');
}
if ($conn_length != "never")
$name .= " " . $name . "_" . date("m_d_Y_H_i", strtotime("+" . $conn_length));
$hosts = file($hosts_path);
if ($wireless)
$hosts[] = "$ip\t$name\n";
else
{
$divider = array_search("# Wireless Hosts\n", $hosts) - 1;
for ($i = count($hosts)-1; $i >= $divider; $i--)
$hosts[$i+1] = $hosts[$i];
$hosts[$divider] = "$ip\t$name\n";
}
file_put_contents($hosts_path, $hosts);
print "
Enable/Disable your connection now.\n";
}
else
print "Security answer incorrect!\n";
}
else
{
// If the remote IP is local, this arp trick will work to get the MAC address
$ip = $_SERVER["REMOTE_ADDR"];
$arp = `ping -c 1 $ip > /dev/null && arp -a | grep '$ip'`;
preg_match("/at (.*) \[ether\] on eth1/U", $arp, $match);
$mac = $match[1];
print "
Welcome to the Garinger wireless network
\n";
print "\n";
}
print "\n";
print "\n";
?>