[Freeipa-devel] [PATCH] 0001: Silence sshd messages during install

[Jan Cholasta]

Hi,

On 9.7.2016 14:46, Ben Lipton wrote:
> On 07/07/2016 11:19 AM, Ben Lipton wrote:
>>
>> Thanks for the review! Comments below.
>>
>>
>> On 07/01/2016 07:42 AM, Martin Basti wrote:
>>>
>>>
>>>
>>> On 29.06.2016 20:46, Ben Lipton wrote:
>>>> The attached patch silences some annoying messages I've been getting
>>>> when upgrading the freeipa-client package on F24:
>>>> """
>>>> WARNING: 'UseLogin yes' is not supported in Fedora and may cause
>>>> several problems.
>> This will be fixed by openssh-7.2p2-9.fc24
>> (https://bugzilla.redhat.com/show_bug.cgi?id=1350347) so we probably
>> shouldn't worry about it.
>>>> Could not load host key: /etc/ssh/ssh_host_dsa_key
>> This is because by default sshd looks for all of
>> /etc/ssh/ssh_host_dsa_key, /etc/ssh/ssh_host_ecdsa_key,
>> /etc/ssh/ssh_host_ed25519_key and /etc/ssh/ssh_host_rsa_key, but
>> Fedora doesn't generate a DSA key by default.
>>>> """
>>>>
>>>> Since the script causing the message only looks at the return code
>>>> from sshd to determine the right options to use, I thought it might
>>>> be ok to discard the output. What do you think?
>>>>
>>>> Ben
>>>>
>>>>
>>>
>>> Hello, I don't like to hiding errors/warnings. Can you determine and
>>> solve the root cause?
>>
>> I definitely agree with this in principle, but in this case the
>> purpose of this code is to try different, potentially wrong,
>> parameters to sshd until it finds a combination that it accepts. It
>> seems like in some environments this would produce error messages that
>> aren't actionable and don't indicate any problem for package function,
>> which is why I didn't think these messages were necessarily worth
>> preserving.
>>
>> On the other hand, if the code makes the wrong decision about sshd
>> version we might be interested in error logs that show why. Can we log
>> this to a file instead of the console, maybe?
>>
>> If you'd prefer just addressing the root cause, a patch that prevents
>> the missing host key error is attached, but it won't stop the error
>> messages showing up when openssh is an older version.
>>
>> Thanks,
>> Ben
>>
>>
> Whoops, realized that my patch created a tempfile and didn't delete it.
> Updated.

I think the first version of the patch was OK. sshd is called only to 
check which set of authorized keys options to use, we don't really care 
about anything else, so we can safely ignore whatever it puts to stderr.

Honza

-- 
Jan Cholasta