Re: [Curdle] Warren Kumari's No Objection on draft-ietf-curdle-ssh-curves-10: (with COMMENT)

["Mark D. Baushke" <[e-mail]>]

Hi Warren,

Warren Kumari writes:
> Mirja beat me to it with the questions re: the additional Copyright
> text -- I'd *thought* I'd seen a reply to that mail, but cannot seem
> to find it at the moment..

My comment was that as I had not introduced the copyright section, I was
not comfortable removing it without approval of the other two authors of
this Draft. I have not yet heard from them on this topic. I have no
objections to the removal myself.

> Also:
>
> "An abort for these purposes is defined as a disconnect of the session
> with an appropriate SSH "protocol error" for the fault provided to or
> by the client. "
>
> Fair enough -- but would it be possible to point at where people can
> go find out what the "appropriate SSH protocol error" is?

Protocol error messages to abort are in Section 11.1 of RFC4253. and the
most likely code would be SSH_DISCONNECT_KEY_EXCHANGE_FAILED (reason
code 3).

See also URL:
https://www.iana.org/assignments/ssh-parameters/ssh-parameters.xhtml#ssh-parameters-3

However, it has been suggested that too narrow a description of the
issue might not be wise.

As this comment has been raised and discussed a few times now. Should I
add a reference?

	An abort for these purposes is defined as a disconnect of the
	session with an appropriate SSH "protocol error" for the fault
	provided to or by the client such as using the reason code
	SSH_DISCONNECT_KEY_EXCHANGE_FAILED for the SSH_MSG_DISCONNECT
	message <xref target="IANA-REASON"/>

I am not happy to be this prescriptive given that I am not certain what
all implementors of this KEX do when the abort happens.

A number of different reason codes might be currently implemented,
including:

           Symbolic name                                reason code
           -------------                                -----------
      SSH_DISCONNECT_PROTOCOL_ERROR                          2
      SSH_DISCONNECT_KEY_EXCHANGE_FAILED                     3
      SSH_DISCONNECT_CONNECTION_LOST                        10
      0xFE000000-0xFFFFFFFF		    Reserved for Private Use


The "IANA_REASON" xref would become this informative reference:

     <reference
         anchor="IANA-REASON"
         target="http://www.iana.org/assignments/ssh-parameters/ssh-parameters.\
xhtml#ssh-parameters-3">
       <front>
         <title>Secure Shell (SSH) Protocol Parameters:
	 Disconnection Messages Reason Codes and Descriptions</title>
         <author>
           <organization>Internet Assigned Numbers Authority (IANA)
           </organization>
         </author>
         <date month="August" year="2019"/>
       </front>
     </reference>


	Thank you,
	-- Mark