Skip to main content
RPC
RPC
Associate III
Jan 21, 2025 4:07 PM UTC
Solved

IP Forwarding

Hello, I have a question about LWIP functionality.

I'd like to know if it's possible to redirect a tcp request received on the pppos interface, to a device that is connected onto the ethernet interface and listening on the desired port.
Thanks in advance!

This topic has been closed for replies.
STeaBest answer
ST Employee
Feb 18, 2025 10:59 AM UTC

Hello @RPC ,

I assume that would be possible as mentioned in LwIP documentation and this can be done by setting 

#define IP_FORWARD   1
(add this to lwipopts.h)

IP_FORWARD==1: Enables the ability to forward IP packets across network interfaces. If you are going to run lwIP on a device with only one network interface, define this to 0. refer to lwIP: IPv4.
Regards


In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.
View in thread

2 replies

STeaBest answer
ST Employee
Feb 18, 2025 10:59 AM UTC

Hello @RPC ,

I assume that would be possible as mentioned in LwIP documentation and this can be done by setting 

#define IP_FORWARD   1
(add this to lwipopts.h)

IP_FORWARD==1: Enables the ability to forward IP packets across network interfaces. If you are going to run lwIP on a device with only one network interface, define this to 0. refer to lwIP: IPv4.
Regards


In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.
    Andrew Neil
    Andrew Neil
    Super User
    Feb 18, 2025 11:16 AM UTC

    https://www.nongnu.org/lwip/2_0_x/group__lwip__opts__ipv4.html#ga881d32ff5ee02af01f758953f1b51d59

    A complex system that works is invariably found to have evolved from a simple system that worked.A complex system designed from scratch never works and cannot be patched up to make it work.
    Terms & ConditionsAccessibility statement