tweak ssh credentials

apss_evaluator · 07-07-2015, 11:21 AM

Hi Linux Guru's

just want to ask if there is a way that I can ssh to target host and the target host will accept the my login but will appear as a different user. Like this:

SOURCE:
[rundeck@host~]ssh rundeck@target

TARGET:
Last login:0705/2015 from rundeck
[user@target ~]

suicidaleggroll · 07-07-2015, 11:52 AM

I don't understand. You want to log in as user1 but have it automatically become user2 once you're logged in? How would that work?

Why don't you just ssh directly to the user you want to be?

apss_evaluator · 07-07-2015, 12:13 PM

Quote:

Originally Posted by suicidaleggroll

I don't understand. You want to log in as user1 but have it automatically become user2 once you're logged in? How would that work?

Why don't you just ssh directly to the user you want to be?

Hi I am also aware of that, but there are some restrictions to the target host on adding a user as "rundeck". Just asking i it is possible

suicidaleggroll · 07-07-2015, 12:50 PM

Is what possible? Please explain your question more clearly, I don't understand what you're asking.

rknichols · 07-07-2015, 12:56 PM

What do you want that is not what you get by using

Code:

ssh -l someuser target_host

apss_evaluator · 07-07-2015, 01:01 PM

Quote:

Originally Posted by suicidaleggroll

Is what possible? Please explain your question more clearly, I don't understand what you're asking.

Just asking if it is possible, if not I'm still okay with it

astrogeek · 07-07-2015, 01:06 PM

What is "it" that you are OK with? I am with suicidal on this, I fully do not understand the question...

apss_evaluator · 07-07-2015, 01:19 PM

Quote:

Originally Posted by astrogeek

What is "it" that you are OK with? I am with suicidal on this, I fully do not understand the question...

sorry if my question is confusing, I still got limited english knowledge, I meant to refer if - is that possible?

to have a rundeck user from host1 connect to host2 but will appear as user@host2 after login

astrogeek · 07-07-2015, 01:25 PM

Quote:

Originally Posted by apss_evaluator

sorry if my question is confusing, I still got limited english knowledge, I meant to refer if - is that possible?

to have a rundeck user from host1 connect to host2 but will appear as user@host2 after login

As asked, the answer is no.

If you need the permissions of user@host after login then you need the login credentials of user@host, so why not just login as user@host in the first place?

suicidaleggroll · 07-07-2015, 01:25 PM

Quote:

Originally Posted by apss_evaluator

sorry if my question is confusing, I still got limited english knowledge, I meant to refer if - is that possible?

to have a rundeck user from host1 connect to host2 but will appear as user@host2 after login

That doesn't really help.

Answer this - Does host2 have a "rundeck" user? Does host2 have a "user" user? Which user do you have the password for? Which user do you want to access files as?

apss_evaluator · 07-07-2015, 01:36 PM

Quote:

Originally Posted by suicidaleggroll

That doesn't really help.

Answer this - Does host2 have a "rundeck" user? Does host2 have a "user" user? Which user do you have the password for? Which user do you want to access files as?

host2 has no rundeck user but has already have "user" user

no specific files needed, lets not stress this out. I think my idea is really impossible :-)

I appreciate for looking on this

jpollard · 07-07-2015, 03:01 PM

I think (not sure) the OP wants the remote user name...

In which case, maybe something like:

http://superuser.com/questions/16316...that-changes-f

can be used. Normally this is disabled (PermitUserEnvironment is set to no), but can be controlled (see manpage on sshd_config) and dthe "AcceptEnv" option

From the manpage on sshd_config:

Code:

     AcceptEnv
             Specifies what environment variables sent by the client will be
             copied into the session's environ(7).  See SendEnv in
             ssh_config(5) for how to configure the client.  Note that envi
             ronment passing is only supported for protocol 2.  Variables are
             specified by name, which may contain the wildcard characters *
             and ?.  Multiple environment variables may be separated by
             whitespace or spread across multiple AcceptEnv directives.  Be
             warned that some environment variables could be used to bypass
             restricted user environments.  For this reason, care should be
             taken in the use of this directive.  The default is not to accept
             any environment variables.

And the entry in the manpage for ssh_config:

Code:

    SendEnv
             Specifies what variables from the local environ(7) should be sent
             to the server.  Note that environment passing is only supported
             for protocol 2.  The server must also support it, and the server
             must be configured to accept these environment variables.  Refer
             to AcceptEnv in sshd_config(5) for how to configure the server.
             Variables are specified by name, which may contain wildcard char
             acters.  Multiple environment variables may be separated by
             whitespace or spread across multiple SendEnv directives.  The
             default is not to send any environment variables.

Now USING it might be a bit tricky - as trying to pass something like "REMOTE_LOGIN" would mean that the environment variable REMOTE_LOGIN has to be initialized before using the ssh command. This could be done via the .login script type of thing - if "REMOTE_LOGIN" doesn't exist, then set it to "$LOGNAME".

It would have to be initialized ONLY if it doesn't exist - if it does exist, then it was "sent" by ssh.

suicidaleggroll · 07-07-2015, 03:10 PM

Quote:

Originally Posted by apss_evaluator

host2 has no rundeck user but has already have "user" user

no specific files needed, lets not stress this out. I think my idea is really impossible :-)

I appreciate for looking on this

As rknichols asked, what are you looking for that isn't already handled by:

ssh user@host2
or
ssh -l user host2

?