smbclient --max-protocol=NT1: why it requres setting MIN protocol too?

[Rowland Penny]

On 25/10/2022 16:45, Michael Tokarev via samba-technical wrote:
> Hi!
> 
> When trying to use current smbclient to connect to, say, a windowsXP 
> machine
> (which implements only NT1 protocol), smbclient has to be told to use lower
> protocol version than it's default - this is intended.
> 
> But the thing is that it doesn't work:
> 
>    $ smbclient --max-protocol=NT1 //testhost/share
>    Unable to initialize messaging context
>    protocol negotiation failed: NT_STATUS_INVALID_PARAMETER_MIX
> 
> Using -m/--max-protocol=NT1 *also* requires setting another option:
> 
>    $ smbclient --max-protocol=NT1 --option='client min protocol = CORE' 
> //testhost/share
> 
> This way it actually works.
> 
> Can't smbclient either warn about this situation, or better yet,
> lower its min protocol automatically if it is greater than
> the requested max protocol?
> 
> Thanks,
> 
> /mjt
> 

I am just trying to understand this, from what I thought I knew. SMB is 
a negotiating protocol, so shouldn't smbclient negotiate the best 
version of SMB to use ? i.e. You shouldn't have to tell it what version 
to use.

Rowland