Anyone knows how to ssh / su - by passing the password initially itself?
Like:
ssh username#hostname -p [password]
pbrun su - unix_owner -p [password]
How can I achieve this?
It shouldn't popup for password or any RSA authentication like yes/no.
I think you will probably need a sudoers file to get stuff done in a su like manner without being prompted for a password.
I have never used ssh without a password prompt, but found this which suggests it can be done...
passing a password in clear text is not intended by ssh.
Try to learn about ssh key authentication (google would help), you won't need to type your password anymore.
ok, more detailed, try this:
on the remote machine
> mkdir -p ~/.ssh #if neccessary
> touch ~/.ssh/authorized_keys2
> chmod go-rwx $HOME/.ssh/authorized_keys2
on your local machine:
> ssh-keygen # if neccessary
> cat ~/.ssh/id_rsa.pub | ssh root#remotehost "cat >> .ssh/authorized_keys2 && chmod 0600 ~/.ssh/authorized_keys2"
A better approach would be using ssh keys, like other answers recommend, but if you really need it, you can use expect for that.
Just create a expect.file like this one:
#!/usr/bin/env expect
set username youruser
set pass yourpassword
set host yourhost
spawn ssh ${username}#${host}
expect -re "password:"
send "${pass}\r"
expect -re "$"
interact
and execute it:
expect expect.file
Can't do it. You're invoking the passwd program on the remote machine. If it had a way to change a password without prompting for the old one, ANYONE could change your password if they got onto your console. You'd still need to pass the password in over the ssh link
As for SSH, you could use RSA keys, and those won't prompt you for passwords.
As for SU, it would have to be hardcoded or you would have to create your own application to serve as a wrapper of sorts.
I don't think you can pass in password directly to the ssh command (It will be stored in your history otherwise). Why don't you use keys to skip the authentication prompt.
Related
I am using ssh to connect to remote server from local.
[siebel#local ~]$ ssh remote
siebel#remote password:
I dont want to input the password manually. I want to write a script in which I will give the password as an input. It will enable me to login without manual action.
I don't want to setup passwordless authentication by ssh-keygen. I tried to use expect but spawn is not working. I don't want to install any other utility also.
As I said its strongly discouraged to hardcode passwords for security reasons but what I will suggest, only if you just can't avoid doing it. is to use sshpass.
You can easily do a:
sudo apt install sshpass
following that the following simple command will do the trick for you.
sshpass -p "PASSWORD" ssh -o StrictHostKeyChecking=no USERNAME#REMOTE_HOST:Custom port number(default is 22)
My issue is that everytime I have to login to a given account on a linux server (there are many) I have to go pull a text file not I have to look at the username and ip.
Example: "ssh some_user#xxx.xxx.xxx.x -pxxxxx"
I want to make my life a little easier by creating a shortcut, e.g. "ssh some_user"...
I searched and could not find an answer, likely not using the right terminology.
Thanks!
You can use the ssh client configuration file (.ssh/config). If you have to type ssh -p 1234 mylogin#my.server.with.a.long.name.com, you can populate your config file with
host server
hostname my.server.with.a.long.name.com
user mylogin
port 1234
Then you can simply type ssh server and it will have the same effect. You can have as many entries in your .ssh/config file as you want and even use wildcards (*)
If you are using a recent version of bash, you can furthermore make use of the command_not_found_handle function:
command_not_found_handle () {
if grep "host $1" ~/.ssh/config &>/dev/null; then
ssh $#
else
printf "Sorry: Command not found: $1\n"
return 127
fi
}
Then you can connect simply with
server
I dont know if I understood your problem correct, but a proper ssh config file make life muuuch easier. No IP, no domain, no password, not even a username.
See the man page: http://linux.die.net/man/5/ssh_config
I like things like ssh vm, or scp vm:... no more scp blablubb#192.168.226.xy:...+ passphrase.
Also see ssh-keygen and ssh-copy-id for asymmetric key exchange. Will get you rid of typing passwords.
Generally I recommend to read a ssh tutorial.
I have 20 machines where I need to create a user and set his password. I can create the accounts and set the passwords using a for loop. The inside of the for loop is given as follows
ssh -t user1#$node_name 'sudo useradd user2'
ssh -t user1#$node_name 'sudo passwd user2'
However, this requires me to input the password for user1 first and then input the new password for user2. I tried it for 2 machines and it works. I however do not like the wasteful effort involved and am guessing there would me a more efficient way of doing so. Any ideas?
To remove the need to enter user1's password, you can mess with the sudo -A or -a options on $node_name to get authentication to happen automatically in some other way.
To remove the need to type user2's password, you can try something like this:
ssh -t user1#$node_name "sudo echo $newpass | useradd user2 --stdin"
It will be helpful if somebody could tell me how to connect to a unix server using username and password as arguments.my username and password is "anitha".
How can i create a shell script which automatically connect to my unix server with this username and password?
I guess you want to remotely connect to your *nix server from network. Base on my guess, to:
connect to remote *nix server, everybody is using SSH
ssh anitha#anitha ip-to-unix-server
automatically connect, write simple bash shell wrap around your ssh connect command and do something, not suggested, you should use ssh password less login (aka public/private key)
#!/usr/bin/env bash
ip=172.16.0.1 #replace 172.16.0.1 with your unix server's ip
username=anitha #your ssh username
password=anitha #your ssh password
command=who #what do you want to do with remote server
arguments= #arguments for your command
expect -c 'spawn ssh $username#$ip ; expect password ; send "$password\n" ; interact'
connect without typing password, you may need to use SSH password less login
Use sshpass if you really need to use non-interactive keyboard-interactive authentication (pun intended) or better switch to using pubkey-based authentication.
Note that passing the password in clear to the ssh client is very lame as the password gets exposed in the publicly-readable process list where it can be read by anyone. sshpass works around this problem by creating a pseudo-terminal and communicating with the ssh client using it, so at least the password is not exposed at runtime.
Step 1:
jsmith#local-host$ [Note: You are on local-host here]
jsmith#local-host$ ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/jsmith/.ssh/id_rsa):[Enter key]
Enter passphrase (empty for no passphrase): [Press enter key]
Enter same passphrase again: [Pess enter key]
Your identification has been saved in /home/jsmith/.ssh/id_rsa.
Your public key has been saved in /home/jsmith/.ssh/id_rsa.pub.
The key fingerprint is:
33:b3:fe:af:95:95:18:11:31:d5:de:96:2f:f2:35:f9 jsmith#local-host
Step 2:
From Local-host, run this One liner for password less ssh connectivity.
cat ~/.ssh/id_dsa.pub | ssh useronanotherserver#anotherservername 'cat >> ~/.ssh/authorized_keys'
You should use expect, which is an extension of tcl that was made specifically for automating login tasks.
Basic ssh login question: could not able to spawn(ssh) using expect
How to interact with the server programattically after you have established the session: Expect Script to Send Different String Outputs
How can you make SSH read the password from stdin, which it doesn't do by default?
based on this post you can do:
Create a command which open a ssh session using SSH_ASKPASS (seek SSH_ASKPASS on man ssh)
$ cat > ssh_session <<EOF
export SSH_ASKPASS="/path/to/script_returning_pass"
setsid ssh "your_user"#"your_host"
EOF
NOTE: To avoid ssh to try to ask on tty we use setsid
Create a script which returns your password (note echo "echo)
$ echo "echo your_ssh_password" > /path/to/script_returning_pass
Make them executable
$ chmod +x ssh_session
$ chmod +x /path/to/script_returning_pass
try it
$ ./ssh_session
Keep in mind that ssh stands for secure shell, and if you store your user, host and password in plain text files you are misleading the tool an creating a possible security gap
You can use sshpass which is for example in the offical debian repositories. Example:
$ apt-get install sshpass
$ sshpass -p 'password' ssh username#server
You can't with most SSH clients. You can work around it with by using SSH API's, like Paramiko for Python. Be careful not to overrule all security policies.
Distilling this answer leaves a simple and generic script:
#!/bin/bash
[[ $1 =~ password: ]] && cat || SSH_ASKPASS="$0" DISPLAY=nothing:0 exec setsid "$#"
Save it as pass, do a chmod +x pass and then use it like this:
$ echo mypass | pass ssh user#host ...
If its first argument contains password: then it passes its input to its output (cat) otherwise it launches whatver was presented after setting itself as the SSH_ASKPASS program.
When ssh encounters both SSH_ASKPASS AND DISPLAY set, it will launch the program referred to by SSH_ASKPASS, passing it the prompt user#host's password:
An old post reviving...
I found this one while looking for a solution to the exact same problem, I found something and I hope someone will one day find it useful:
Install ssh-askpass program (apt-get, yum ...)
Set the SSH_ASKPASS variable (export SSH_ASKPASS=/usr/bin/ssh-askpass)
From a terminal open a new ssh connection without an undefined TERMINAL variable (setsid ssh user#host)
This looks simple enough to be secure but did not check yet (just using in a local secure context).
Here we are.
FreeBSD mailing list recommends the expect library.
If you need a programmatic ssh login, you really ought to be using public key logins, however -- obviously there are a lot fewer security holes this way as compared to using an external library to pass a password through stdin.
a better sshpass alternative is :
https://github.com/clarkwang/passh
I got problems with sshpass, if ssh server is not added to my known_hosts sshpass will not show me any message, passh do not have this problem.
I'm not sure the reason you need this functionality but it seems you can get this behavior with ssh-keygen.
It allows you to login to a server without using a password by having a private RSA key on your computer and a public RSA key on the server.
http://www.linuxproblem.org/art_9.html