From 4d70042a3817a1df7de8a932cefe218c7223f934 Mon Sep 17 00:00:00 2001
From: Jason <xjasonlyu@gmail.com>
Date: Thu, 19 Dec 2019 22:15:49 +0800
Subject: [PATCH] tune ttl and mtu

---
 core/c/custom/lwipopts.h | 1 +
 core/lwip.go             | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/core/c/custom/lwipopts.h b/core/c/custom/lwipopts.h
index 8145066..bbf9ef8 100644
--- a/core/c/custom/lwipopts.h
+++ b/core/c/custom/lwipopts.h
@@ -36,6 +36,7 @@
 #define NO_SYS 1
 #define LWIP_TIMERS 1
 
+#define IP_DEFAULT_TTL 64
 #define LWIP_ARP 0
 #define ARP_QUEUEING 0
 #define IP_FORWARD 0
diff --git a/core/lwip.go b/core/lwip.go
index 0753f25..0635e03 100644
--- a/core/lwip.go
+++ b/core/lwip.go
@@ -118,4 +118,7 @@ func init() {
 	// Now the loop interface is just the first element in
 	// `C.netif_list`, i.e. `*C.netif_list`.
 	lwipInit()
+
+	// Set MTU.
+	C.netif_list.mtu = 1500
 }