Re: SSH tunnel key exchange methods

Hi Dave

On Mon, Nov 30, 2015 at 10:41 AM, Akshay Joshi <akshay(dot)joshi(at)enterprisedb
.com> wrote:

> Hi Dave
>
> On Fri, Nov 27, 2015 at 3:01 PM, Dave Page <dpage(at)pgadmin(dot)org> wrote:
>
>> On Fri, Nov 27, 2015 at 9:23 AM, Sven <svoop_6cedifwf9e(at)delirium(dot)ch>
>> wrote:
>> >> The key exchange methods offered when opening an SSH tunnel are all
>> >> SHA1 and therefore too weak:
>> >>
>> >> [sshd] fatal: Unable to negotiate with xxx.xxx.xxx.xxx: no matching
>> >> key exchange method found. Their offer:
>> >> diffie-hellman-group14-sha1,diffie-hellman-group-exchange-sha1,
>> >> diffie-hellman-group1-sha1 [preauth]
>> >
>> > Any news on this? If there's no easy way to add safer kexes, I suggest
>> > you disable the SSH feature altogether. SHA1 is dead and IMO nobody
>> > should trust a connection established with SHA1 kexes in order to talk
>> > to databases.
>>
>> Akshay, you know that code best of all. How do we enable safer kexes?
>>
>
> Today I'll look into it on priority and update accordingly.
>

I have found that "diffie-hellman-group-exchange-sha256" support has
been added to the libssh2 code on September 24, it's not released yet.
Please check https://github.com/libssh2/libssh2/pull/48 . Today I have
tried to update the libssh2, but facing some compilation issues which needs
to be fixed. I am working on it and then check do we need to change our
logic or libssh2 will automatically used "diffie-hellman
-group-exchange-sha256".

>
>> --
>> Dave Page
>> Blog: http://pgsnake.blogspot.com
>> Twitter: @pgsnake
>>
>> EnterpriseDB UK: http://www.enterprisedb.com
>> The Enterprise PostgreSQL Company
>>
>
>
>
> --
> *Akshay Joshi*
> *Principal Software Engineer *
>
>
>
> *Phone: +91 20-3058-9517Mobile: +91 976-788-8246*
>

--
*Akshay Joshi*
*Principal Software Engineer *

*Phone: +91 20-3058-9517Mobile: +91 976-788-8246*