Re: [lwip-users] ppp-new IP forwarding only works one direction (Ethernet to PPP)

[LMao]

Hi Sylvain,

Good news, I got it work  with your patch plus the replacement of 
(PBUF_LINK_HLEN +2), however, set ETH_PAD_SIZE to 2 actually doesn't work. It 
seems fail at ARP and infinitely repeat with the following debug messages:

ethernet_input: dest:ff:ff:ff:ff:ff:ff, src:c8:d7:19:ee:1f:fc, type:806
etharp_update_arp_entry: 192.168.0.211 - c8:d7:19:ee:1f:fc
etharp_find_entry: found empty entry 0
etharp_find_entry: no empty entry found and not allowed to recycle
etharp_arp_input: incoming ARP request
etharp_arp_input: ARP request was not for us.
ethernet_input: dest:ff:ff:ff:ff:ff:ff, src:c8:d7:19:ee:1f:fc, type:806
etharp_update_arp_entry: 192.168.0.211 - c8:d7:19:ee:1f:fc
etharp_find_entry: found empty entry 0
etharp_find_entry: no empty entry found and not allowed to recycle
etharp_arp_input: incoming ARP request
etharp_arp_input: ARP request was not for us.
ethernet_input: dest:ff:ff:ff:ff:ff:ff, src:c8:d7:19:ee:1f:fc, type:806
etharp_update_arp_entry: 192.168.0.211 - c8:d7:19:ee:1f:fc
etharp_find_entry: found empty entry 0
etharp_find_entry: no empty entry found and not allowed to recycle
etharp_arp_input: incoming ARP request
etharp_arp_input: ARP request was not for us.

The reason I originally found it didn't work because I forgot to set the 
default route in my Linux PPP server. Now we need a more elegant way to fix the 
problem. 

Thanks,

Charles

-----Original Message-----
From: address@hidden [mailto:address@hidden On Behalf Of Sylvain Rochet
Sent: Thursday, April 10, 2014 3:49 PM
To: Mailing list for lwIP users
Subject: Re: [lwip-users] ppp-new IP forwarding only works one direction 
(Ethernet to PPP)

Hello Charles,

On Thu, Apr 10, 2014 at 06:37:02PM +0000, address@hidden wrote:
> Below is more debug information and hope it's helpful for fixing the problem.
> 
> Regarding the code stalled at early stage, that's hardware related. I 
> am using ARM7 (AT91SAM7 to be specific), so the data alignment is 4 
> and PBUF_LINK_HLEN is 14 by default, so I replaced all PBUF_LINK_HLEN 
> in the patch with (PBUF_LINK_HLEN + 2). It fixed the run-time problem 
> which keep the code running fine. Now I can build-up the PPP 
> connection. However, the patch seems fix the pbuf issue but it 
> actually breaks the traffic from Ethernet to PPP side which was fine 
> before the patch. If you need me do any test, please let me know.

Humm, you should set ETH_PAD_SIZE to 2 in your lwipopts.h instead of doing that.

Sylvain