mod: remove dev and use np to specify nextHop gateway

XinRoom · Jan 12, 2023 · 780f5f4 · 780f5f4
1 parent 56e7eb6
commit 780f5f4
Show file tree

Hide file tree

Showing 4 changed files with 48 additions and 10 deletions.
diff --git a/cmd/go-portScan.go b/cmd/go-portScan.go
@@ -30,7 +30,7 @@ var (
 	rateP     int
 	iL        string
 	devices   bool
-	dev       string
+	nexthop   string
 	httpx     bool
 	netLive   bool
 	bp        bool
@@ -44,7 +44,7 @@ func parseFlag(c *cli.Context) {
 	ipStr = c.String("ip")
 	iL = c.String("iL")
 	portStr = c.String("port")
-	dev = c.String("dev")
+	nexthop = c.String("nexthop")
 	devices = c.Bool("devices")
 	pn = c.Bool("Pn")
 	rateP = c.Int("rateP")
@@ -206,7 +206,7 @@ func run(c *cli.Context) error {
 	option := port.Option{
 		Rate:    rate,
 		Timeout: timeout,
-		Dev:     dev,
+		NextHop: nexthop,
 	}
 	if sT {
 		// tcp
@@ -348,9 +348,10 @@ func main() {
 				Value: true,
 			},
 			&cli.StringFlag{
-				Name:  "dev",
-				Usage: "specified pcap dev name",
-				Value: "",
+				Name:    "nexthop",
+				Aliases: []string{"nh"},
+				Usage:   "specified nexthop gw add to pcap dev",
+				Value:   "",
 			},
 			&cli.IntFlag{
 				Name:    "rate",

diff --git a/core/port/port.go b/core/port/port.go
@@ -105,7 +105,7 @@ type OpenIpPort struct {
 type Option struct {
 	Rate    int    // 每秒速度限制, 单位: s, 会在1s内平均发送, 相当于每个包之间的延迟
 	Timeout int    // TCP连接响应延迟, 单位: ms
-	Dev     string // pcap dev name
+	NextHop string // pcap dev name
 }
 
 // ParsePortRangeStr 解析端口字符串

diff --git a/core/port/syn/device.go b/core/port/syn/device.go
@@ -44,6 +44,28 @@ func GetIfaceMac(ifaceAddr net.IP) (src net.IP, mac net.HardwareAddr) {
 	return nil, nil
 }
 
+// GetMacByGw get srcIp srcMac devname by gw
+func GetMacByGw(gw net.IP) (srcIp net.IP, srcMac net.HardwareAddr, devname string, err error) {
+	srcIp, srcMac = GetIfaceMac(gw)
+	if srcIp == nil {
+		err = errors.New("can not find this dev by gw")
+		return
+	}
+	srcIp = srcIp.To4()
+	devices, err := pcap.FindAllDevs()
+	if err != nil {
+		return
+	}
+	for _, d := range devices {
+		if len(d.Addresses) > 0 && d.Addresses[0].IP.String() == srcIp.String() {
+			devname = d.Name
+			return
+		}
+	}
+	err = errors.New("can not find this dev")
+	return
+}
+
 // GetRouterV4 get ipv6 router by dst ip
 func GetRouterV4(dst net.IP) (srcIp net.IP, srcMac net.HardwareAddr, gw net.IP, devName string, err error) {
 	// 同网段
@@ -74,6 +96,9 @@ func GetRouterV4(dst net.IP) (srcIp net.IP, srcMac net.HardwareAddr, gw net.IP,
 	srcIp = srcIp.To4()
 	devName, _ = GetDevByIp(srcIp)
 	if srcIp == nil || err != nil || srcMac == nil {
+		if err == nil {
+			err = fmt.Errorf("err")
+		}
 		return nil, nil, nil, "", fmt.Errorf("no router, %s", err)
 	}
 	return

diff --git a/core/port/syn/syn.go b/core/port/syn/syn.go
@@ -49,12 +49,24 @@ func NewSynScanner(firstIp net.IP, retChan chan port.OpenIpPort, option port.Opt
 		return
 	}
 
-	// get router info
-	srcIp, srcMac, gw, devName, err := GetRouterV4(firstIp)
+	var devName string
+	var srcIp net.IP
+	var srcMac net.HardwareAddr
+	var gw net.IP
+
+	// specify dev
+	if option.NextHop != "" {
+		gw = net.ParseIP(option.NextHop).To4()
+		srcIp, srcMac, devName, err = GetMacByGw(gw)
+	} else {
+		// get router info
+		srcIp, srcMac, gw, devName, err = GetRouterV4(firstIp)
+	}
 	if err != nil {
 		return
 	}
-	if devName == "" && option.Dev == "" {
+
+	if devName == "" {
 		err = errors.New("get router info fail: no dev name")
 		return
 	}