From 583b2a5ace5be91abf64c2073275d2bf4ca61e46 Mon Sep 17 00:00:00 2001
From: Dreamacro <8615343+Dreamacro@users.noreply.github.com>
Date: Thu, 14 Oct 2021 22:54:43 +0800
Subject: [PATCH] Change: use interface HardwareAddr for dhcp discovery

---
 component/dhcp/dhcp.go | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/component/dhcp/dhcp.go b/component/dhcp/dhcp.go
index b2ca6928f2..b7e9f5069d 100644
--- a/component/dhcp/dhcp.go
+++ b/component/dhcp/dhcp.go
@@ -3,9 +3,10 @@ package dhcp
 import (
 	"context"
 	"errors"
-	"math/rand"
 	"net"
 
+	"github.com/Dreamacro/clash/component/iface"
+
 	"github.com/insomniacslk/dhcp/dhcpv4"
 )
 
@@ -23,7 +24,12 @@ func ResolveDNSFromDHCP(context context.Context, ifaceName string) ([]net.IP, er
 
 	result := make(chan []net.IP, 1)
 
-	discovery, err := dhcpv4.NewDiscovery(randomHardware(), dhcpv4.WithBroadcast(true), dhcpv4.WithRequestedOptions(dhcpv4.OptionDomainNameServer))
+	ifaceObj, err := iface.ResolveInterface(ifaceName)
+	if err != nil {
+		return nil, err
+	}
+
+	discovery, err := dhcpv4.NewDiscovery(ifaceObj.HardwareAddr, dhcpv4.WithBroadcast(true), dhcpv4.WithRequestedOptions(dhcpv4.OptionDomainNameServer))
 	if err != nil {
 		return nil, err
 	}
@@ -80,15 +86,3 @@ func receiveOffer(conn net.PacketConn, id dhcpv4.TransactionID, result chan<- []
 		return
 	}
 }
-
-func randomHardware() net.HardwareAddr {
-	addr := make(net.HardwareAddr, 6)
-
-	addr[0] = 0xff
-
-	for i := 1; i < len(addr); i++ {
-		addr[i] = byte(rand.Intn(254) + 1)
-	}
-
-	return addr
-}