Re: [lwip-devel] LWIP IPv4 does not accept broadcast packets when configured interface IP address is 0.0.0.0

[Indan Zupancic]

Hello Andrei,

On 2022-09-22 19:23, Tutuianu, Andrei wrote:
> I did some digging and I found out that the function
> ip4_input_accept does not accept the packet because the
> IP address of the interface is not valid (it checks if
> the interface is up and the IP is not IPADDR_ANY). Is
> the check for invalid address really necessary if the
> IP packet is a broadcast?

You can define LWIP_IP_ACCEPT_UDP_PORT in lwipopt.h to add an exception:

#define LWIP_IP_ACCEPT_UDP_PORT(dst_port) ((dst_port) == 
PP_NTOHS(12345))

Alternatively, have a non-zero default IP address for initial 
configuration.

Greetings,

Indan