Re: [lwip-users] https mbed TLS lwip

[Mário Luzeiro]

Hi Trampas,

I had an experience with lwip, mbedTLS and https (all using latest versions 
from repositories)
It took a loooong time to me to make it (kinda) work.

The problems I had (some similar than yours and lots of others) was a 
combinations of multiple factors:
- MCU drivers bugs (on my case the ST DMA issue).
- MCU limited resources: use the faster options you can get for encryption, 
limit the use of memory and allow TLS cache usage.
- Memory and parameter configurations: since browsers can fire 4 .. 8 
connections to get the page, you will need to allow all that connections to be 
accepted.
- Parameter configurations: you will have to fine tune your parameters to your 
use case and resources limitation.

You will have to debug a lot, using webbrowser, wireshark and so on.. until o 
find the best parameters for you.
What you are describing looks the browser can make the first connections and 
then it cannot make new connections because there are no slots left.

Mario

________________________________________
From: lwip-users <lwip-users-bounces+mrluzeiro=address@hidden> on behalf of 
Trampas Stern <address@hidden>
Sent: 18 February 2020 18:40
To: Mailing list for lwIP users
Subject: [lwip-users] https mbed TLS lwip

I am having a problem with the lwip and mbed TLS.  I find that usually after 
reboot chrome can access my lwip https server and the first load of the web 
page seems to work. If I refresh the website then it seems to fail I have 
noticed in Chrome that I get the following errors:

[image.png]

Since the firmware usually works without a problem after reboot I assume there 
is some sort of firmware bug (malloc not being free, etc).  I have not been 
able to nail down what the problem is.

Anyone have any suggestions?

Thanks
Trampas