How to automate SSH login with password?

Question

How to automate SSH login with password? I'm configuring my test VM, so heavy security is not considered. SSH chosen for acceptable security with minimal configuration.

ex)

echo password | ssh id@server

This is not working.

I remember I did this with some tricks somebody guided me, but I can't remember now the trick I used...

Answer 1

Don't use a password. Generate a passphraseless ssh key and push it to your VM.

If you already have an ssh key, you can skip this step... Just hit enter for the key and both passphrases:

$ ssh-keygen -t rsa -b 2048
Generating public/private rsa key pair.
Enter file in which to save the key (/home/username/.ssh/id_rsa): 
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/username/.ssh/id_rsa.
Your public key has been saved in /home/username/.ssh/id_rsa.pub.

Copy your keys to the target server:

$ ssh-copy-id id@server
id@server's password: 
Now try logging into the machine, with "ssh 'id@server'", and check in:

  .ssh/authorized_keys

to make sure we haven't added extra keys that you weren't expecting.

Finally check logging in...

$ ssh id@server

id@server:~$ 

You may also want to look into using ssh-agent if you want to try keeping your keys protected with a passphrase.

Answer 2

Sure you don't want to use SSH keys rather than passwords? That way it's both secure and automatic.

Answer 3

Hi I hope this guide helps you:

http://jcsalterego.github.com/2011/02/04/getting-comfortable-with-ssh.html

It goes over keyless entry and aliases which might be helpful to you.

Answer 4

why so complicated?

Generate a rsa keypair:

# ssh-keygen

then copy it on the server with one simple command:

# ssh-copy-id hostname

you can now log in without password:

# ssh hostname

Answer 5

This might not be any use to you, but you can do it with Perl:

#!/usr/bin/perl
use warnings;
use strict;

use Net::SSH::Perl;
my $host = 'remote.serv.er';
my $user = 'root';
my $pass = 'hunter2';
my $ssh = Net::SSH::Perl->new('$host');
$ssh->login('$user', '$pass') or die "Oh noes! $!";

Answer 6

Use expect:

#!/usr/bin/expect -f
#  ./ssh.exp password 192.168.1.11 id
set pass [lrange $argv 0 0]
set server [lrange $argv 1 1]
set name [lrange $argv 2 2]

spawn ssh $name@$server
match_max 100000
expect "*?assword:*"
send -- "$pass\r"
send -- "\r"
interact

Example:

# ./1.ex password localhost ooshro
spawn ssh ooshro@localhost
ooshro@localhost's password: 
Linux ubuntu-1010-server-01 2.6.35-25-generic-pae #44-Ubuntu SMP Fri Jan 21 19:01:46 UTC 2011 i686 GNU/Linux
Ubuntu 10.10

Welcome to Ubuntu!
 * Documentation:  https://help.ubuntu.com/
Last login: Tue Mar  1 12:41:12 2011 from localhost