Re: draft-baushke-ssh-dh-group-sha2-01 (was Re: DH group exchange)

[Damien Miller <djm%mindrot.org@localhost>]

On Thu, 11 Feb 2016, Mark D. Baushke wrote:

> Hi denis,
> 
> Two questions:
> 
>   a) Should the draft list all of the Key Exchange Method Names 
>      in the https://www.ietf.org/assignments/ssh-parameters/ssh-parameters.xml
>      table?
> 
>      If so, does the following capture the desired state?
>   
> Key Exchange Method Name              Reference     Note
> diffie-hellman-group-exchange-sha1    RFC4419       NOT RECOMMENDED
> diffie-hellman-group-exchange-sha256  RFC4419       OPTIONAL
> diffie-hellman-group1-sha1            RFC4253       NOT RECOMMENDED
> diffie-hellman-group14-sha1           RFC4253       OPTIONAL
> ecdh-sha2-nistp256                    RFC5656       REQUIRED
> ecdh-sha2-nistp384                    RFC5656       REQUIRED
> ecdh-sha2-nistp521                    RFC5656       REQUIRED
> ecdh-sha2-*                           RFC5656       OPTIONAL
> ecmqv-sha2                            RFC5656       OPTIONAL
> gss-gex-sha1-*                        RFC4462       NOT RECOMMENDED
> gss-group1-sha1-*                     RFC4462       NOT RECOMMENDED
> gss-group14-sha1-*                    RFC4462       NOT RECOMMENDED
> gss-*                                 RFC4462       OPTIONAL
> rsa1024-sha1                          RFC4432       NOT RECOMMENDED
> rsa2048-sha256                        RFC4432       OPTIONAL
> diffie-hellman-group14-sha256         This Draft    OPTIONAL
> diffie-hellman-group15-sha256         This Draft    REQUIRED
> diffie-hellman-group16-sha512         This Draft    RECOMMENDED
> diffie-hellman-group17-sha512         This Draft    OPTIONAL
> diffie-hellman-group18-sha512         This Draft    OPTIONAL

list looks ok to me

>   b) Is it desirable to specify all of group 14, 15, 16, 17, and 18 as
>      to the hashing algorithm to be used NOW? Or, is it better to drop
>      15 and 17 for now? If so, is it desirable for group14-sha256 to be
>      REQUIRED, RECOMMENDED, or OPTIONAL ?

+1 to dropping the odd-numbered groups and onlist listing group14/16/18