Sending commands via ssh argument

[Mark Castagna]

Hello All,
I can use ssh to send a telnet command to a remote host and have the login prompt returned.

Example,
From hostA as any user, ssh -l userA hostB telnet hostC after entering the password for userA I get a login prompt from hostC.

Preliminarily, I've tried rksh, removing /etc/PATH but, it seems to me that ssh only authenticates against a user (etc/passwd) but, doesn't use any shell environment. I'm perplexed.

Thanks,
Mark Castagna

[Steven E. Protter]

Two things:

1) Try pure ssh. ssh replaces telnet. you can send ssh commands in the command string ssh root@disk.itool.com "./etc/profile;ssh sys2.itool.com $commands"

2) Set up the ssh for password free authentication by exchanging public keys. See the doc I'm attaching.

SEP

[Charlie Rubeor]

Could you provide a little more info on what you are trying to accomplish?

The login prompt from hostC is a result of the telnet command. Sending the telnet command via ssh will encrypt the connection between hostA and hostB, but the connection between hostB and hostC will remain clear text. If you are trying to eliminate the login and password prompts, then use ssh on all three hosts, along with the public keys.

AFAIK, ssh does require a valid user and will use the shell as listed in /etc/passwd. I would ssh to hostB, verify that the shell environment is correct on hostB. Then ssh/telnet to hostC and verify the shell environment on hostC.

[Mark Castagna]

Thanks for the document. That will answer some other questions I have.

I probably didn't make myself completely clear. I don't want unscrupulous users to be able to use ssh to access telnet (or any other command).
Thanks again,
Mark

[Charlie Rubeor · Accepted solution]

Thank you, that makes much more sense.

You should be able to configure sudo to limit your users to specific commands, as well as eliminating the ability to pass arguments. i.e., "sudo ssh hostA" would be ok, but "sudo ssh hostA ls" would not be ok.

http://hpux.connect.org.uk/hppd/hpux/Sysadmin/sudo-1.6.7p5/