User Defined DUID

User may define a DUID to use in System->Advanced->Networking. The
entered DUID is validated for composition and length, if valid it is
stored in the config.xml. On call of wan_dhcp6_configure() the DUID is
written to file to be read by dhcp6c on launch.

3 files changed, 65 insertions, 0 deletions

diff --git a/src/etc/inc/interfaces.inc b/src/etc/inc/interfaces.inc
index be68bdd..eaac41c 100644
--- a/src/etc/inc/interfaces.inc
+++ b/src/etc/inc/interfaces.inc
@@ -3868,6 +3868,13 @@ function interface_dhcpv6_configure($interface = "wan", $wancfg) {
 	$wanif = get_real_interface($interface, "inet6");
 	$dhcp6cconf = "";
 
+	if (!empty($config['system']['global-v6duid'])) {
+		// Write the DUID file
+		if(!write_dhcp6_duid($config['system']['global-v6duid'])) {
+		    log_error(gettext("Failed to write user DUID file!"));
+		}
+	}
+	
 	if ($wancfg['adv_dhcp6_config_file_override']) {
 		// DHCP6 Config File Override
 		$dhcp6cconf = DHCP6_Config_File_Override($wancfg, $wanif);
diff --git a/src/etc/inc/util.inc b/src/etc/inc/util.inc
index 528fe0e..f8fceea 100644
--- a/src/etc/inc/util.inc
+++ b/src/etc/inc/util.inc
@@ -2542,4 +2542,40 @@ function validateipaddr(&$addr, $type, $label, &$err_msg, $alias=false) {
 
 	return false;
 }
+
+
+/* returns true if $dhcp6duid is a valid duid entrry */
+function is_duid($dhcp6duid) {
+	$values = explode(":", $dhcp6duid);
+	if (count($values) != 16 || strlen($dhcp6duid) != 47) {
+		return false;
+	}
+	for ($i = 0; $i < 16; $i++) {
+		if (ctype_xdigit($values[$i]) == false)
+			return false;
+		if (hexdec($values[$i]) < 0 || hexdec($values[$i]) > 255)
+			return false;
+	}
+	return true;
+}
+
+/* Write the DHCP6 DUID file */
+function write_dhcp6_duid($duidstring) {
+	// Create the hex array from the dhcp6duid config entry and write to file
+	global $g;
+ 	
+ 	if(!is_duid($duidstring)) {
+		log_error(gettext("Error: attempting to write DUID file - Invalid DUID detected"));
+		return false;
+	}
+	$temp = str_replace(":","",$duidstring);
+	$duid_binstring = pack("H*",$temp);
+	if ($fd = fopen("{$g['vardb_path']}/dhcp6c_duid", "wb")) {
+		fwrite($fd, $duid_binstring);
+		fclose($fd);
+		return true;
+	}
+	log_error(gettext("Error: attempting to write DUID file - File write error"));
+	return false;
+}
 ?>
diff --git a/src/usr/local/www/system_advanced_network.php b/src/usr/local/www/system_advanced_network.php
index 06a4e2d..b453045 100644
--- a/src/usr/local/www/system_advanced_network.php
+++ b/src/usr/local/www/system_advanced_network.php
@@ -40,6 +40,7 @@ require_once("shaper.inc");
 $pconfig['ipv6nat_enable'] = isset($config['diag']['ipv6nat']['enable']);
 $pconfig['ipv6nat_ipaddr'] = $config['diag']['ipv6nat']['ipaddr'];
 $pconfig['ipv6allow'] = isset($config['system']['ipv6allow']);
+$pconfig['global-v6duid'] = $config['system']['global-v6duid'];
 $pconfig['prefer_ipv4'] = isset($config['system']['prefer_ipv4']);
 $pconfig['sharednet'] = $config['system']['sharednet'];
 $pconfig['disablechecksumoffloading'] = isset($config['system']['disablechecksumoffloading']);
@@ -83,6 +84,18 @@ if ($_POST) {
 			unset($config['system']['prefer_ipv4']);
 		}
 
+		if (!empty($_POST['global-v6duid'])) {
+			$_POST['global-v6duid'] = strtolower(str_replace("-", ":", $_POST['global-v6duid']));
+			if (!is_duid($_POST['global-v6duid'])) {
+				$input_errors[] = gettext("A valid DUID must be specified");
+			} else {
+				$config['system']['global-v6duid'] = $_POST['global-v6duid'];
+			}
+		}
+		else {
+			unset($config['system']['global-v6duid']);
+		}
+
 		if ($_POST['sharednet'] == "yes") {
 			$config['system']['sharednet'] = true;
 			system_disable_arp_wrong_if();
@@ -186,6 +199,15 @@ $section->addInput(new Form_Checkbox(
 ))->setHelp('By default, if IPv6 is configured and a hostname resolves IPv6 and IPv4 addresses, '. 
 	'IPv6 will be used. If this option is selected, IPv4 will be preferred over IPv6.');
 
+$section->addInput(new Form_Input(
+	'global-v6duid',
+	'DHCP6 DUID',
+	'text',
+	$pconfig['global-v6duid'],
+	['placeholder' => 'xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx']
+	))->setWidth(9)->sethelp('Enter the DUID to use here. Use this option if using RAM Disk, as the DUID will be lost on reboot. The existing DUID may be found in var/db/dhcp6_duid.' .'<br />' .
+			'NOTE: Do not use this option with multiple DHCP6 interfaces.');
+
 $form->add($section);
 $section = new Form_Section('Network Interfaces');