From 7260153439e5ec264b8eb5f7364bd2c73fdb0e39 Mon Sep 17 00:00:00 2001
From: Max Lv <max.c.lv@gmail.com>
Date: Fri, 31 Jul 2015 16:38:25 +0800
Subject: [PATCH] add log for possible ip fragmentation

---
 src/udprelay.c | 14 ++++++--------
 src/udprelay.h |  4 ++--
 2 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/src/udprelay.c b/src/udprelay.c
index a9cb2de7..9d3fa677 100644
--- a/src/udprelay.c
+++ b/src/udprelay.c
@@ -639,10 +639,9 @@ static void remote_recv_cb(EV_P_ ev_io *w, int revents)
         goto CLEAN_UP;
     }
 
-    // Drop large packets > default MTU
-    if (buf_len > MTU) {
-        LOGE("[udp] drop large packets, size: %d", (int)buf_len);
-        goto CLEAN_UP;
+    // packet size > default MTU
+    if (verbose && buf_len > MTU) {
+        LOGE("[udp] possible ip fragment, size: %d", (int)buf_len);
     }
 
 #ifdef UDPRELAY_LOCAL
@@ -833,10 +832,9 @@ static void server_recv_cb(EV_P_ ev_io *w, int revents)
 #endif
 #endif
 
-    // Drop large packets > default MTU
-    if (buf_len > MTU) {
-        LOGE("[udp] drop large packets, size: %d", (int)buf_len);
-        goto CLEAN_UP;
+    // packet size > default MTU
+    if (verbose && buf_len > MTU) {
+        LOGE("[udp] possible ip fragment, size: %d", (int)buf_len);
     }
 
     /*
diff --git a/src/udprelay.h b/src/udprelay.h
index b6879ab6..e48da211 100644
--- a/src/udprelay.h
+++ b/src/udprelay.h
@@ -37,9 +37,9 @@
 
 #include "common.h"
 
-#define MAX_UDP_PACKET_SIZE (2 * 1024) // large enough for a typical MTU 1500
+#define MAX_UDP_PACKET_SIZE (65507)
 
-#define MTU 1421 // 1492 - 1 - 28 - 2 - 40 = 1421, the default MTU for UDP relay
+#define MTU 1397 // 1492 - 1 - 28 - 2 - 64 = 1397, the default MTU for UDP relay
 
 struct server_ctx {
     ev_io io;