From a51cc8075d9ba279306ead148cb5fdbbdee3ff28 Mon Sep 17 00:00:00 2001
From: Junxiao Shi <git@mail1.yoursunny.com>
Date: Tue, 10 Dec 2024 09:48:23 +0000
Subject: [PATCH] fix gateway detection

---
 hostinfo.go | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/hostinfo.go b/hostinfo.go
index 3dc620d..74364d9 100644
--- a/hostinfo.go
+++ b/hostinfo.go
@@ -34,13 +34,19 @@ func gatherHostInfo() (hi HostInfo, e error) {
 		logEntry.Error("netlink.LinkByIndex error", zap.Error(e))
 		return hi, nil
 	}
+
 	routes, e := nl.RouteList(link, unix.AF_INET6)
 	if e != nil {
 		logEntry.Error("netlink.RouteList error", zap.Error(e))
 		return hi, nil
 	}
+
 	for _, route := range routes {
-		if route.Dst == nil {
+		maskLen := 0
+		if route.Dst != nil {
+			maskLen, _ = route.Dst.Mask.Size()
+		}
+		if maskLen == 0 {
 			hi.GatewayIP, _ = netip.AddrFromSlice(route.Gw)
 		}
 	}