Question about inbound udp broadcasts

[Ian Boston]

Hi,
I am sorry if this has been asked before, I searched and could not find an answer.

Are UDP broadcasts (ie port > 1023, dest 255.255.255.255) the the local network (ie wifi) of a chromeos device supposed to arrive at applications (eg android apps) running on that device ? [1] indicates that the packets should be routed as expected.

I have a embedded device broadcasting packets which appear on an app running on Android on the local net, but not on ChromeOS running the same app.  ie the app on ChromeOS is non functional on ChromeOS when it relies on a UDP broadcast from an external host.  

In dev mode, I traced packets through iptables to the ingress_port_firewall target which lead me to patchpanel where I spotted [1]. (I am assuming ChromeOS and ChromiumOS are mostly the same in this area)

Best Regards
Ian


1 https://chromium.googlesource.com/chromiumos/platform2/+/refs/heads/main/patchpanel/broadcast_forwarder.cc#39