Disable DHCP server on interfaces with subnet >= 31. Fixes #6930

1 files changed, 14 insertions, 2 deletions

diff --git a/src/usr/local/www/interfaces.php b/src/usr/local/www/interfaces.php
index 292cd00..234a0c6 100644
--- a/src/usr/local/www/interfaces.php
+++ b/src/usr/local/www/interfaces.php
@@ -548,8 +548,20 @@ if ($_POST['apply']) {
 		$input_errors[] = gettext("The interface description cannot contain only numbers.");
 	}
 	/* input validation */
-	if (isset($config['dhcpd']) && isset($config['dhcpd'][$if]['enable']) && (!preg_match("/^staticv4/", $_POST['type']))) {
-		$input_errors[] = gettext("The DHCP Server is active on this interface and it can be used only with a static IP configuration. Please disable the DHCP Server service on this interface first, then change the interface configuration.");
+	if (isset($config['dhcpd']) && isset($config['dhcpd'][$if]['enable'])) {
+		if (!preg_match("/^staticv4/", $_POST['type'])) {
+			$input_errors[] = gettext("The DHCP Server is active " .
+			    "on this interface and it can be used only with " .
+			    "a static IP configuration. Please disable the " .
+			    "DHCP Server service on this interface first, " .
+			    "then change the interface configuration.");
+		} elseif (!empty($_POST['subnet']) && $_POST['subnet'] >= 31) {
+			$input_errors[] = gettext("The DHCP Server is active " .
+			    "on this interface and it can be used only with " .
+			    "IPv4 subnet < 31. Please disable the " .
+			    "DHCP Server service on this interface first, " .
+			    "then change the interface configuration.");
+		}
 	}
 	if (isset($config['dhcpdv6']) && isset($config['dhcpdv6'][$if]['enable']) && ($_POST['type6'] != "staticv6" && $_POST['type6'] != "track6")) {
 		$input_errors[] = gettext("The DHCP6 Server is active on this interface and it can be used only with a static IPv6 configuration. Please disable the DHCPv6 Server service on this interface first, then change the interface configuration.");