multicast messages

[Monki]

Hello FRANCESCO,
one question is, is there the possibility of receiving multicast messages in the Annex or is it easy to implement

monki

[cicciocb]

UDP multicast?

[Monki]

Yes

[Monki]

Yes

[cicciocb]

yes, I think it should work.

[Monki]

Hi Francesco,
I tried it with
udp.begin 5353
onudp udpreceive
wait
udpreceive:
v$ = udp.read$ data
vlog v$
return
But I don't get any message. With b4X (another basic variant) it works

[cicciocb]

I just tried with an esp32-s3 with the toolkit and using the address .255 I receive the messages

image.png

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[Monki]

hello Francesco,
Thanks for your effort, but I think you confused multicast with broadcast, I have a link here https://book.hacktricks.xyz/network-ser ... t-dns-mdns
found in which the functionality is explained

[cicciocb]

Yes you are right, I confused multicast with broadcast but you confused UDP with DNS

Yes, I implemented it in the version 1.51.1 but I removed it in the following version replacing it with NETBIOS

image.png

[Monki]

Good morning Francesco

I have several smart home devices (shelly rgbw2), these send their status via Udp to the multicast address 224.01.1.187 port 5683.
As mentioned above, I created an app for this purpose with B4X, which also works well.
b4x is a basic language that then compiles the code into native bytecode. Here is an excerpt of the Java inline code, perhaps it will be more understandable


Sub CreateMulticastSocket(EventName As String, Port As Int, Group As String)
Dim multi As JavaObject
multi.InitializeNewInstance("java.net.MulticastSocket", Array(Port))
Dim inet As JavaObject
multi.RunMethod("joinGroup", Array(inet.InitializeStatic("java.net.InetAddress").RunMethod("getByName", Array(Group))))
Dim jo As JavaObject = Me
jo.RunMethod("SetMulticastSocket", Array(EventName, multi, udp))
End sub

#if java
import java.net.*;
public void SetMulticastSocket(String EventName, MulticastSocket socket, anywheresoftware.b4a.objects.SocketWrapper.UDPSocket udp) {
udp.init(getBA(), EventName, 8192, socket);
}
#end if