Fix static DHCP address validation

1) Use gen_subnetv4 and gen_subnetv4_max rather than doing the guts of the calculation inline. (The ~gen_subnet_mask_long($ifcfgsn) thing was the cause of the problem)
2) Add validation checks to stop people using the network address or broadcast address as a statically allocated DHCP address.

Should fix Redmine #5651

1 files changed, 13 insertions, 4 deletions

diff --git a/src/usr/local/www/services_dhcp_edit.php b/src/usr/local/www/services_dhcp_edit.php
index 3a6b753..b07bb0d 100644
--- a/src/usr/local/www/services_dhcp_edit.php
+++ b/src/usr/local/www/services_dhcp_edit.php
@@ -252,12 +252,21 @@ if ($_POST) {
 			}
 		}
 
-		$lansubnet_start = ip2ulong(long2ip32(ip2long($ifcfgip) & gen_subnet_mask_long($ifcfgsn)));
-		$lansubnet_end = ip2ulong(long2ip32(ip2long($ifcfgip) | (~gen_subnet_mask_long($ifcfgsn))));
-		if ((ip2ulong($_POST['ipaddr']) < $lansubnet_start) ||
-		    (ip2ulong($_POST['ipaddr']) > $lansubnet_end)) {
+		$lansubnet_start = ip2ulong(gen_subnetv4($ifcfgip, $ifcfgsn));
+		$lansubnet_end = ip2ulong(gen_subnetv4_max($ifcfgip, $ifcfgsn));
+		$ipaddr_int = ip2ulong($_POST['ipaddr']);
+		if (($ipaddr_int < $lansubnet_start) ||
+		    ($ipaddr_int > $lansubnet_end)) {
 			$input_errors[] = sprintf(gettext("The IP address must lie in the %s subnet."), $ifcfgdescr);
 		}
+
+		if ($ipaddr_int == $lansubnet_start) {
+			$input_errors[] = sprintf(gettext("The IP address cannot be the %s network address."), $ifcfgdescr);
+		}
+
+		if ($ipaddr_int == $lansubnet_end) {
+			$input_errors[] = sprintf(gettext("The IP address cannot be the %s broadcast address."), $ifcfgdescr);
+		}
 	}
 
 	if (($_POST['gateway'] && !is_ipaddrv4($_POST['gateway']))) {