From 52215ec63accf390761aa0e0108a8031e99093e8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=BA=90=E6=96=87=E9=9B=A8?=
 <41315874+fumiama@users.noreply.github.com>
Date: Fri, 13 May 2022 23:13:30 +0800
Subject: [PATCH] drop commandline mtu

---
 README.md               | 14 ++++++++------
 config/cfg.go           |  1 +
 main.go                 |  3 +--
 upper/services/wg/wg.go | 16 ++++++++--------
 4 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/README.md b/README.md
index 56bb4e5..8295b2c 100644
--- a/README.md
+++ b/README.md
@@ -7,7 +7,7 @@
 ## Usage
 > If you are running in windows, remember to select the `wintun.dll` of your arch in `lower/wintun` and place it alongside the compiled exe
 ```bash
-wg [-c config.yaml] [-d|w] [-g] [-h] [-m mtu] [-p] [-l log.txt]
+wg [-c config.yaml] [-d|w] [-g] [-h] [-p] [-l log.txt]
 ```
 #### Instructions
 ```bash
@@ -18,21 +18,21 @@ wg [-c config.yaml] [-d|w] [-g] [-h] [-m mtu] [-p] [-l log.txt]
   -h    display this help
   -l string
         write log to file (default "-")
-  -m int
-        set the mtu of wg (default 1432)
   -p    show my publickey
   -w    only show logs above warn level
 ```
 
-- **macos mojave**: max mtu (under ipv4 endpoint) is `9159`
-- **ipv6 endpoint**: the recommand mtu is `1280~1400` to prevent the big segments from being dropped
-
 ## Config file example
+
+- **macos mojave**: max mtu (under ipv4 endpoint) is `9159`
+- **ipv6 endpoint**: the recommand mtu is `1280~1500` to prevent the big segments from being dropped
+
 ```yaml
 IP: 192.168.233.1
 SubNet: 192.168.233.0/24
 PrivateKey: 暲菉斂狧污爉窫擸紈卆帞蔩慈睠庮扝憚瞼縀
 EndPoint: 0.0.0.0:56789
+MTU: 1500
 Peers:
   -
       IP: "192.168.233.2"
@@ -42,6 +42,7 @@ Peers:
       AllowedIPs: ["192.168.233.2/32"]
       KeepAliveSeconds: 0
       QueryList: ["192.168.233.3"]
+      MTU: 1400
       QuerySeconds: 10
       AllowTrans: false
   -
@@ -50,6 +51,7 @@ Peers:
       PublicKey: 牢喨粷詸衭譛浾蘹櫠砙杹蟫瑳叩刋橋経挵蘀
       EndPoint: ""
       AllowedIPs: ["192.168.233.3/32"]
+      MTU: 1300
       KeepAliveSeconds: 0
       AllowTrans: false
 ```
\ No newline at end of file
diff --git a/config/cfg.go b/config/cfg.go
index 4a3faf9..d65301a 100644
--- a/config/cfg.go
+++ b/config/cfg.go
@@ -14,6 +14,7 @@ type Config struct {
 	SubNet     string `yaml:"SubNet"`
 	PrivateKey string `yaml:"PrivateKey"`
 	EndPoint   string `yaml:"EndPoint"`
+	MTU        int64  `yaml:"MTU"`
 	Peers      []Peer `yaml:"Peers"`
 }
 
diff --git a/main.go b/main.go
index 7cec9f4..7d4401a 100644
--- a/main.go
+++ b/main.go
@@ -21,7 +21,6 @@ func main() {
 	gen := flag.Bool("g", false, "generate key pair")
 	showp := flag.Bool("p", false, "show my publickey")
 	file := flag.String("c", "config.yaml", "specify conf file")
-	mtu := flag.Int("m", 1500-68, "set the mtu of wg")
 	debug := flag.Bool("d", false, "print debug logs")
 	warn := flag.Bool("w", false, "only show logs above warn level")
 	logfile := flag.String("l", "-", "write log to file")
@@ -129,7 +128,7 @@ func main() {
 	}
 
 	defer w.Stop()
-	w.Run(upper.ServiceWireGold, upper.ServiceWireGold, uint16(*mtu))
+	w.Run(upper.ServiceWireGold, upper.ServiceWireGold)
 }
 
 func displayHelp(hint string) {
diff --git a/upper/services/wg/wg.go b/upper/services/wg/wg.go
index 173a826..e2bc0a8 100644
--- a/upper/services/wg/wg.go
+++ b/upper/services/wg/wg.go
@@ -2,8 +2,8 @@ package wg
 
 import (
 	"errors"
-	"fmt"
 	"net"
+	"strconv"
 
 	base14 "github.com/fumiama/go-base16384"
 	curve "github.com/fumiama/go-x25519"
@@ -48,13 +48,13 @@ func NewWireGold(c *config.Config) (wg WG, err error) {
 	return
 }
 
-func (wg *WG) Start(srcport, destport, mtu uint16) {
-	wg.init(srcport, destport, mtu)
+func (wg *WG) Start(srcport, destport uint16) {
+	wg.init(srcport, destport)
 	go wg.me.ListenFromNIC()
 }
 
-func (wg *WG) Run(srcport, destport, mtu uint16) {
-	wg.init(srcport, destport, mtu)
+func (wg *WG) Run(srcport, destport uint16) {
+	wg.init(srcport, destport)
 	_, err := wg.me.ListenFromNIC()
 	if err != nil {
 		logrus.Panicln(err)
@@ -65,7 +65,7 @@ func (wg *WG) Stop() {
 	_ = wg.me.Close()
 }
 
-func (wg *WG) init(srcport, dstport, mtu uint16) {
+func (wg *WG) init(srcport, dstport uint16) {
 	cidrsmap := make(map[string]bool, 32)
 	_, mysubnet, err := net.ParseCIDR(wg.c.SubNet)
 	if err != nil {
@@ -93,10 +93,10 @@ func (wg *WG) init(srcport, dstport, mtu uint16) {
 		MyIPwithMask: wg.c.IP + "/32",
 		MyEndpoint:   wg.c.EndPoint,
 		PrivateKey:   &wg.key,
-		NIC:          lower.NewNIC(wg.c.IP, wg.c.SubNet, fmt.Sprintf("%d", mtu), cidrs...),
+		NIC:          lower.NewNIC(wg.c.IP, wg.c.SubNet, strconv.FormatInt(wg.c.MTU, 64), cidrs...),
 		SrcPort:      srcport,
 		DstPort:      dstport,
-		MTU:          mtu,
+		MTU:          uint16(wg.c.MTU),
 	})
 
 	for _, peer := range wg.c.Peers {