svn commit: r303716 - head/crypto/openssh

[Andrey Chernov]

On 07.08.2016 20:43, Andrey Chernov wrote:
> On 07.08.2016 20:37, Slawa Olhovchenkov wrote:
>> On Sun, Aug 07, 2016 at 08:34:55PM +0300, Andrey Chernov wrote:
>>
>>> On 07.08.2016 20:31, Andrey Chernov wrote:
>>>> On 07.08.2016 19:14, Bruce Simpson wrote:
>>>>> On 07/08/16 15:40, Warner Losh wrote:
>>>>>> That’s a cop-out answer. We, as a project, need to articulate to our
>>>>>> users, whom we care about, why this rather obnoxious hit to usability
>>>>>> was taken. The answer must be more complete than “We just disabled
>>>>>> it because upstream disabled it for reasons we’re too lazy to explain
>>>>>> or document how to work around"
>>>>>
>>>>> Alcatel-Lucent OmniSwitch 6800 login broken (pfSense 2.3.2 which
>>>>> accepted the upstream change, workaround no-go)
>>>>>
>>>>> [2.3.2-RELEASE][root at gw.lab]/root: ssh -l admin
>>>>> -oKexAlgorithms=+diffie-hellman-group1-sha1 192.168.1.XXX
>>>>> Fssh_ssh_dispatch_run_fatal: Connection to 192.168.1.XXX port 22: DH GEX
>>>>> group out of range
>>>>>
>>>>
>>>> DH prime size must be at least 2048, openssh now refuse lower values.
>>>> Commonly used DH size 1024 can be easily broken. See https://weakdh.org
>>>>
>>> diffie-hellman-group1-sha1 use DH 1024 and insecure sha1 both.
>>
>> IMHO, this is wrong choise: totaly lost of control now vs teoretical
>> compromise of control in the future.
> 
> Please note that it was not my choice and I can't answer what to do with
> non-upgradeable hardware question, address it to the author. I just tell
> you _why_ it happens.
> 

BTW, compromise is practical enough. From https://weakdh.org/ "A close
reading of published NSA leaks shows that the agency's attacks on VPNs
are consistent with having achieved such a break."