I'm writing a C Shell program that will be doing su or sudo or ssh. They all want their passwords in console input (the TTY) rather than stdin or the command line.
Does anybody know a solution?
Setting up password-less sudo is not an option.
expect could be an option, but it's not present on my stripped-down system.
For sudo there is a -S option for accepting the password from standard input. Here is the man entry:
-S The -S (stdin) option causes sudo to read the password from
the standard input instead of the terminal device.
This will allow you to run a command like:
echo myPassword | sudo -S ls /tmp
As for ssh, I have made many attempts to automate/script it's usage with no success. There doesn't seem to be any build-in way to pass the password into the command without prompting. As others have mentioned, the "expect" utility seems like it is aimed at addressing this dilemma but ultimately, setting up the correct private-key authorization is the correct way to go when attempting to automate this.
I wrote some Applescript which prompts for a password via a dialog box and then builds a custom bash command, like this:
echo <password> | sudo -S <command>
I'm not sure if this helps.
It'd be nice if sudo accepted a pre-encrypted password, so I could encrypt it within my script and not worry about echoing clear text passwords around. However this works for me and my situation.
For ssh you can use sshpass: sshpass -p yourpassphrase ssh user#host.
You just need to download sshpass first :)
$ apt-get install sshpass
$ sshpass -p 'password' ssh username#server
For sudo you can do this too:
sudo -S <<< "password" command
I've got:
ssh user#host bash -c "echo mypass | sudo -S mycommand"
Works for me.
The usual solution to this problem is setuiding a helper app that performs the task requiring superuser access:
http://en.wikipedia.org/wiki/Setuid
Sudo is not meant to be used offline.
Later edit: SSH can be used with private-public key authentication. If the private key does not have a passphrase, ssh can be used without prompting for a password.
Maybe you can use an expect command?:
expect -c 'spawn ssh root#your-domain.com;expect password;send "your-password\n";interact
That command gives the password automatically.
This can be done by setting up public/private keys on the target hosts you will be connecting to.
The first step would be to generate an ssh key for the user running the script on the local host, by executing:
ssh-keygen
Enter file in which to save the key (/home/myuser/.ssh/id_rsa): <Hit enter for default>
Overwrite (y/n)? y
Then enter a blank password. After that, copy your ssh key onto the target host which you will be connecting to.
ssh-copy-id <remote_user>#<other_host>
remote_user#other_host's password: <Enter remote user's password here>
After registering the ssh keys, you would be able to perform a silent ssh remote_user#other_host from you local host.
When there's no better choice (as suggested by others), then man socat can help:
(sleep 5; echo PASSWORD; sleep 5; echo ls; sleep 1) |
socat - EXEC:'ssh -l user server',pty,setsid,ctty
EXEC’utes an ssh session to server. Uses a pty for communication
between socat and ssh, makes it ssh’s controlling tty (ctty),
and makes this pty the owner of a new process group (setsid), so
ssh accepts the password from socat.
All of the pty,setsid,ctty complexity is necessary and, while you might not need to sleep as long, you will need to sleep. The echo=0 option is worth a look too, as is passing the remote command on ssh's command line.
Take a look at expect linux utility.
It allows you to send output to stdio based on simple pattern matching on stdin.
ssh -t -t me#myserver.io << EOF
echo SOMEPASSWORD | sudo -S do something
sudo do something else
exit
EOF
Set SSH up for Public Key Authentication, with no pasphrase on the Key. Loads of guides on the net. You won't need a password to login then. You can then limit connections for a key based on client hostname. Provides reasonable security and is great for automated logins.
echo <password> | su -c <command> <user>
This is working.
a better sshpass alternative is: passh
https://github.com/clarkwang/passh
Login to a remote server
$ passh -p password ssh user#host
Run a command on remote server
$ passh -p password ssh user#host date
other methods to pass the password
-p The password (Default: `password')
-p env: Read password from env var
-p file: Read password from file
here I explained why it is better than sshpass, and other solutions.
You can also pass various parameters as follows:
echo password | echo y | sudo -S pacman -Syu
(Although that's a bad idea, it's just an example)
I had the same problem. dialog script to create directory on remote pc.
dialog with ssh is easy. I use sshpass (previously installed).
dialog --inputbox "Enter IP" 8 78 2> /tmp/ip
IP=$(cat /tmp/ip)
dialog --inputbox "Please enter username" 8 78 2> /tmp/user
US=$(cat /tmp/user)
dialog --passwordbox "enter password for \"$US\" 8 78 2> /tmp/pass
PASSWORD = $(cat /tmp/pass)
sshpass -p "$PASSWORD" ssh $US#$IP mkdir -p /home/$US/TARGET-FOLDER
rm /tmp/ip
rm /tmp/user
rm /tmp/pass
greetings from germany
titus
Building on #Jahid's answer, this worked for me on macOS 10.13:
ssh <remote_username>#<remote_server> sudo -S <<< <remote_password> cat /etc/sudoers
I once had a use case where I needed to run Sudo and ssh in the same command without stdin specifying all the variables needed.
This is the command I used
echo sudopassword | sudo -S -u username sshpass -p extsshpassword ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no username#ipaddress " CMD on external machine"
Breaking that command into pieces!
This will allow you to run commands through your machine using Superuser:
echo password | sudo -S -u username
This will allow you to pass ssh password and execute commands on external machines:
sshpass -p sshpassword ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no username#ipaddress " CMD on external machine"
make sure you install the sudo and openssh packages on your machine.
One way would be to use read -s option .. this way the password characters are not echoed back to the screen. I wrote a small script for some use cases and you can see it in my blog:
http://www.datauniv.com/blogs/2013/02/21/a-quick-little-expect-script/
USE:
echo password | sudo command
Example:
echo password | sudo apt-get update; whoami
Hope It Helps..
You can provide password as parameter to expect script.
su -c "Command" < "Password"
Hope it is helpful.
We are trying to write a PowerShell script that invokes an external application -- a Redis client (redis-cli.exe) -- and then sends multiple commands to that .exe. We have no issue sending individual commands like the below:
& redis-cli -h localhost -p 6379 SMEMBERS someKey
The problem is that this will start a Redis client, issue a single command, close the client, and then return control to PowerShell. We need to issue multiple commands in a transaction. For example, here are the commands that we want to send to the client:
MULTI
DEL someKey
DEL someSet
EXEC
The Redis client does support sending a LUA script string as a command, but this unfortunately doesn't support the MULTI/EXEC transactional commands. In other words, we need to be able to issue multiple commands like I listed above.
Since redis-cli appears to read input from STDIN you could feed it an array with the command strings like this:
'MULTI', 'EXEC' | & redis-cli -h localhost -p 6379
Using echo (alias for Write-Output) is not required for feeding the array into the pipeline.
You could also store the command array in a variable first:
$cmds = 'MULTI', 'EXEC'
$cmds | & redis-cli -h localhost -p 6379
i am tasked with Perl to ssh into another server and stop/start/restart the process if it is not already started.
i will break this down into small chunks:
::how can i ssh into a server, and read a pid file and bring back the #?::
i can do this: system("ssh serverid.gcsc.att.com -l myid -i /home/myid/.ssh/authorized_keys 'kill -9 1234'"); just fine, kill the process after authenticating into the server.
but how do i read a pid file/any file on that server, and get the value into a variable so that i can then ssh and kill the process?
Easiest way is with backticks.
my $output = `ssh server -l myid -i /home/myid/.ssh/authorized_keys some_command`;
$output will contain the output of your ssh command.
I am trying to get the output of a command in a variable and checking whether its matching with other variable.
$login1=`ssh ****************** date`;
This command when typed manually will expect a prompt " Password: " . When i run it from the script it is ruuning that command and printing that prompt waiting for user to enter, but i dont need that. I just need to get that output and compare
if($login1=~ /Password:/)
{
print " yes";
}
else
{
print "No ";
}
However the script is just stopping at Password prompt . Please suggest me on how to achieve this .
You might want to look at the -f flag for ssh:
-f Requests ssh to go to background just before command execution.
This is useful if ssh is going to ask for passwords or
passphrases, but the user wants it in the background. This
implies -n. The recommended way to start X11 programs at a
remote site is with something like ssh -f host xterm.
If you want to avoid passwords, set up a public/private key pair with no passphrase (dangerous, but much less dangerous than putting a password in a script) and copy the public key to the remote site. IIRC, it goes something like this:
localhost $ ssh-keygen -b 2048 -t ecdsa -N '' -f ./datekey
localhost $ scp ./datekey.pub remotehost:/tmp
localhost $ ssh remotehost
(login)
remotehost $ cat /tmp/datekey.pub >> ~/.ssh/authorized_keys
remotehost $ logout
localhost $ ssh -i ./datekey remotehost date
Make sure you store ./datekey somewhere no other user can access it at all -- not even read access.
If you're just trying to detect, you might simply need to feed it EOF to get it to move along:
$login1=`ssh ****************** date < /dev/null`;