我搜索了如何使用自定義以太網類型發送原始以太網數據包，但很多人都在談論 tcp 和 udp 協議。我需要打開一個原始套接字，獲取所有具有我自定義以太網類型的數據包，讀取有效負載并發送回具有不同自定義以太網類型的數據包。func main() { //set promiscuos mode cmd := exec.Command("ifconfig", "eth0", "promisc") err := cmd.Run() if err != nil { fmt.Println("Error: " + err.Error()) return } //open raw socket with custom ethertype_1 and bind to interface fd, err := syscall.Socket(syscall.AF_PACKET, syscall.SOCK_RAW, Htons(ETHER_TYPE_1)) if err != nil { fmt.Println("Error: " + err.Error()) return } err = syscall.BindToDevice(fd, "eth0") if err != nil { fmt.Println("Error: " + err.Error()) return } f := os.NewFile(uintptr(fd), fmt.Sprintf("fd %d", fd)) for { buf := make([]byte, 1024) numRead, err := f.Read(buf) if err != nil { fmt.Println(err) } go ReadSocket(buf, numRead) }func ReadSocket(buf []byte, numRead int) { packet := BufToEthPacket(buf, numRead) fmt.Printf("Destination MAC: % X\n", packet.dstMac) fmt.Printf("Source MAC: % X\n", packet.srcMac) fmt.Printf("ether type: %X\n", packet.ethType) fmt.Printf("Payload: % X\n", packet.payload) var myPacket EthPacket myPacket.srcMac = packet.dstMac myPacket.dstMac = packet.srcMac myPacket.ethType = ETHER_TYPE_2 myPacket.payload = packet.payload var myBuf = EthPacketToBuf(myPacket) //open raw socket with custom ethertype_2 and bind to interface fd, err := syscall.Socket(syscall.AF_PACKET, syscall.SOCK_RAW, Htons(ETHER_TYPE_2)) if err != nil { fmt.Println("Error: " + err.Error()) return } err = syscall.BindToDevice(fd, "eth0") if err != nil { fmt.Println("Error: " + err.Error()) return }}我收到了數據包，但f.Write(myBuf)返回以下錯誤：Error: write fd 5: no such device or address我做錯了什么？
1 回答
海綿寶寶撒
TA貢獻1809條經驗 獲得超8個贊
Usingos.Write將在后臺執行write系統調用，這意味著實際文件。要將數據“寫入”到網絡套接字，您需要使用sendto系統調用。
以下示例使用自定義以太類型發送數據。所以只是一個帶有一些數據的以太網數據包。
package main
import (
"log"
"net"
"os"
"syscall"
)
func main() {
ifname := os.Args[1]
iface, err := net.InterfaceByName(ifname)
if err != nil {
log.Fatal("get link by name:", err)
}
srcMac := iface.HardwareAddr
if len(srcMac) == 0 {
srcMac = []byte{0, 0, 0, 0, 0, 0}
}
dstMac := []byte{0x00, 0x01, 0x02, 0x03, 0x04, 0x05}
fd, _ := syscall.Socket(syscall.AF_PACKET, syscall.SOCK_RAW, int(htons(syscall.ETH_P_ALL)))
addr := syscall.SockaddrLinklayer{
Ifindex: iface.Index,
Halen: 6, // Ethernet address length is 6 bytes
Addr: [8]uint8{
dstMac[0],
dstMac[1],
dstMac[2],
dstMac[3],
dstMac[4],
dstMac[5],
},
}
ethHeader := []byte{
dstMac[0], dstMac[1], dstMac[2], dstMac[3], dstMac[4], dstMac[5],
srcMac[0], srcMac[1], srcMac[2], srcMac[3], srcMac[4], srcMac[5],
0x12, 0x34, // your custom ethertype
}
// Your custom data
p := append(ethHeader, []byte("Hello World")...)
err = syscall.Sendto(fd, p, 0, &addr)
if err != nil {
log.Fatal("Sendto:", err)
}
}
// htons converts a short (uint16) from host-to-network byte order.
func htons(i uint16) uint16 {
return (i<<8)&0xff00 | i>>8
}
- 1 回答
- 0 關注
- 144 瀏覽
添加回答
舉報
0/150
提交
取消