Dropbear on bare-metal ARM Cortex-M3?

[Farrell Aultman]

Freddie,

I wouldn't waste my time with it.  You'll have to find or write a
POSIX layer.  Also,
dropbear makes liberal use of dynamic memory and without an MMU you'll run into
memory fragmentation.  In addition, you'll likely suffer from terrible
performance on the M3 if
you can even get it small enough to fit into flash and run within the
confines of your RAM.

In short, I recommend picking a processor with a MMU and run Linux.  Another
option is to use a COTS like Mocana.  But that can be expensive.

Farrell

On Tue, Jul 31, 2012 at 7:07 AM, Freddie Chopin <freddie_chopin at op.pl> wrote:
> Hi!
>
> I was wondering whether it's possible (in a reasonable amount of time) to port
> Dropbear to bare-metal platform - one without an OS (like Linux), but with RTOS
> (FreeRTOS) that provides tasks, queues and synchronization (semaphores +
> mutexes) + LwIP TCP/IP stack?
>
> I would require a very minimal implementation of SSH server, without all
> possible encryption options (the code/RAM footprint has to be low) and without
> all possible features - ideally only simpliest SSH server that can pass received
> strings to other parts of code and transfer strings from code via SSH to
> connected client. Of course I'm talking only about command-line interface.
>
> If Dropbear is not a good option for such task, do you have any other
> recommendations?
>
> Thx in advance for your help!
>
> 4\/3!!
>
> FCh
>