[CentOS] Q: respecting .ssh/id_rsa

Fri May 8 15:28:24 UTC 2015
Kirk Bocek <t004 at kbocek.com>


On 5/8/2015 7:22 AM, Valeri Galtsev wrote:
> On Fri, May 8, 2015 8:58 am, James B. Byrne wrote:
>> While attempting to debug something else I ran across this:
>>
>> ssh -vvv somehost
>> . . .
>> debug1: Connection established.
>> debug1: permanently_set_uid: 0/0
>> debug1: identity file /root/.ssh/identity type -1
>> debug1: identity file /root/.ssh/identity-cert type -1
>> debug3: Not a RSA1 key file /root/.ssh/id_rsa.
>> debug2: key_type_from_name: unknown key type '-----BEGIN'
>> debug3: key_read: missing keytype
>> debug3: key_read: missing whitespace
>> . . .
>>
>> However if I verify the key I see this:
>>
>> ssh-keygen -l -f ~/.ssh/id_rsa.pub
>> 4096 08:70:3b:92:4c:96:1c:6a:03:a4:ae:66:8d:9e:6c:93
>> /root/.ssh/id_rsa.pub (RSA)
>>
>> Which seems ok to me. The permissions also seem ok:
>>
>> .ssh]# ll
>> total 40
>> -rw-------. 1 root root  3863 Oct 11  2012 authorized_keys
>> -rw-------. 1 root root  3243 Aug  9  2012 id_rsa
>> -rw-r--r--. 1 root root   757 Aug  9  2012 id_rsa.pub
>> -rw-r--r--. 1 root root 11071 May  8 09:42 known_hosts
> When checking permissions don't forget to check permissions on parent
> directories (all levels up to the /). E.g., if your home directory is
> world writable, ssh will ignore authorized_keys as well, as the above
> permissions _can_ be changed by everybody. The same is true if / is
> ridiculously world writable (I've never seen that myself, but I do mean:
> check all levels of what the path ~/.ssh is).
>
> It's not clear from your description, but I'm sure you have the following
> right: id_rsa and id_rsa.pub is a pair you have on local machine (the one
> you ssh from). autorized_keys is on the remote machine (the one you
> connect to), and it contains the contents of id_rsa.pub that you have on
> local machine (i.e. you copied id_rsa.pub from local machine to remote and
> dumped it into ~/.ssh/autorized_keys on it).
>
> I would also check that in sshd config file (usually:
> /etc/ssh/sshd_config) on remote machine you do have line
>
> PubkeyAuthentication yes
>
> Good luck!
>
> Valeri
>
>> The password-less connections complete in any case but I am perplexed
>> as to what is the problem with the root identity key that ssh is
>> reporting.
>>
>> Can anyone explain to me what this means?
>>
>>

Also check that the selinux context on all files and directories are set 
to "ssh_home_t".

 From the home dir:

#chcon -R -t ssh_home_t .ssh