Status DHCP Leases handle expire never

Note: We can let the code pass "never" (or any other unexpected stuff)
to adjust_gmt()
adjust_gmt() should anyway handle the case when strtotime() cannot
understand the input string and thus returns false. In that case we
return the input string as-is so it will be displayed as the time. That
way the user will see it and can report easily whatever other unexpected
char data was in the leases file.
It also prevents "false" (zero) being converted to the date-time string
and thus becoming the Unix epoch 1 Jan 1970 on the display.
Latest forum report of this kind of thing:
https://forum.pfsense.org/index.php?topic=90083.0

1 files changed, 16 insertions, 6 deletions

diff --git a/usr/local/www/status_dhcp_leases.php b/usr/local/www/status_dhcp_leases.php
index 191d9f5..24c41b8 100644
--- a/usr/local/www/status_dhcp_leases.php
+++ b/usr/local/www/status_dhcp_leases.php
@@ -107,9 +107,12 @@ function adjust_gmt($dt) {
 	}
 	if ($dhcpleaseinlocaltime == "yes") {
 		$ts = strtotime($dt . " GMT");
-		return strftime("%Y/%m/%d %I:%M:%S%p", $ts);
-	} else
-		return $dt;
+		if ($ts !== false) {
+			return strftime("%Y/%m/%d %I:%M:%S%p", $ts);
+		}
+	}
+	/* If we did not need to convert to local time or the conversion failed, just return the input. */
+	return $dt;
 }
 
 function remove_duplicate($array, $field)
@@ -186,9 +189,16 @@ foreach($leases_content as $lease) {
 				$f = $f+3;
 				break;
 			case "ends":
-				$leases[$l]['end'] = $data[$f+2];
-				$leases[$l]['end'] .= " " . $data[$f+3];
-				$f = $f+3;
+				if ($data[$f+1] == "never") {
+					// Quote from dhcpd.leases(5) man page:
+					// If a lease will never expire, date is never instead of an actual date.
+					$leases[$l]['end'] = gettext("Never");
+					$f = $f+1;
+				} else {
+					$leases[$l]['end'] = $data[$f+2];
+					$leases[$l]['end'] .= " " . $data[$f+3];
+					$f = $f+3;
+				}
 				break;
 			case "tstp":
 				$f = $f+3;