(I think raw sockets may require admin privs; at least Claude suggested this https://go.dev/play/p/ZdqkgiGyr-v )
On Saturday, March 22, 2025 at 2:48:01 PM UTC Jason E. Aten wrote: > The Claude 3 Sonnet LLM gives this, which runs fine (I tested) on Windoze > and the Go playground: > > https://go.dev/play/p/YjNQ5Ru_eLq > > On Saturday, March 22, 2025 at 10:12:19 AM UTC Kanak Bhatia wrote: > >> Hey everyone, >> >> I’m trying to learn how to build a raw UDP socket in Go (on Windows) >> using golang.org/x/sys/windows. My goal is to send and receive raw UDP >> packets. >> >> *What I’m trying to do:* >> >> 1. *Create a raw socket:* >> >> socket, err := windows.Socket(windows.AF_INET, windows.SOCK_RAW, >> windows.IPPROTO_IP) if err != nil { fmt.Printf("Error creating socket: >> %v\n", err) return } defer windows.Closesocket(socket) >> >> *2. Send a UDP message:* >> func sendUDPPacket(socket windows.Handle, srcPort, destPort int, targetIP >> string, data string) error { >> payload := []byte(data) >> packet := createUDPHeader(srcPort, destPort, payload) >> >> // Define the target address (IP + Port) >> addr := windows.SockaddrInet4{Port: destPort} >> copy(addr.Addr[:], []byte{127, 0, 0, 1}) // Sending to localhost >> >> // Send the packet >> return windows.Sendto(socket, packet, 0, &addr) >> } >> >> *3. Receive a UDP message:* >> func receiveUDPPacket(socket windows.Handle) { >> buffer := make([]byte, 1024) >> >> for { >> // Receive data from the socket >> n, from, err := windows.Recvfrom(socket, buffer, 0) >> if err != nil { >> fmt.Println("Error receiving data:", err) >> break >> } >> >> // Extract the header (8 bytes) and payload >> fmt.Printf("📩 Received raw packet (%d bytes): %x\n", n, buffer[:n]) >> fmt.Printf("👉 Payload: %s\n", buffer[8:n]) >> fmt.Printf("👉 From: %+v\n", from) >> } >> } >> ------------------------------ >> >> *The problem:* >> >> Sending works perfectly, but receiving fails immediately with this error: >> go run main.go 8000 8001 >> 🚀 Type your message (type 'exit' to quit): >> 💬 Enter message: Error receiving data: An invalid argument was supplied. >> hello >> ✅ Message sent! >> 💬 Enter message: hello 2 >> ✅ Message sent! >> >> >> *I’m stuck and would love some help:* >> >> I’m still learning how raw sockets and protocols actually work. >> >> -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion visit https://groups.google.com/d/msgid/golang-nuts/609decdc-f9f2-4501-99a9-2f41863110bcn%40googlegroups.com.
