server limits commands to MAX_CMD_LEN

[Matt Johnston]

Hi Szabolcs,

4k sounds like an OK limit, I'll increase that. Handling
larger limits like shells (200k+?) would be harder -
Dropbear expects SSH packets to be under 32kB.

Cheers,
Matt

On Wed, Jul 01, 2015 at 06:32:36PM +0200, Szabolcs Nagy wrote:
> some of my long ssh commands failed with
> 
> exec request failed on channel 0
> 
> and it seems the dropbear server rejected them because of the limits
> in sysoptions.h:
> 
> #define MAX_CMD_LEN 1024 /* max length of a command */
> //...
> #define MAX_STRING_LEN 2400 /* Sun SSH needs this long for algos */
> 
> i assume these affect scp too, so i think it would make sense
> if they were at least the historical PATH_MAX (4K).
> 
> (MAX_CMD_LEN is probably not needed if MAX_STRING_LEN already
> limits the command buffer size).
> 
> or am i expected to manually tweak these limits if i want
> to run commands using long filenames?
> 
> thanks