Connect via SSH and change password?

Question

linux

In general, there is such a task. There is an admin panel in which there is a functionality to change the user's password.
The idea is this: we call a PHP script that logs in via SSH to the server under root and changes the user's password. We know the root password.
From my predecessor I got this code:

#!/usr/bin/expect
set USER [lindex $argv 0]
set PASS [lindex $argv 1]
set HOST [lindex $argv 2]

spawn ssh [email protected]$HOST

expect "word:"
send "123456\r"
expect "$*"
send "echo \"$USER:$PASS\" | chpasswd  \r"
send "exit\r"
expect eof

Called with PHP like this:

system("./do.py ".$user." ".$new_password." ".$did->did);

The above code does not work, perhaps the problem is incorrect handling of expect.
And it seems to me that there is a more normal option for changing the password. Unfortunately, to put additional software and libraries on the server and clients can not. I can't upload anything to other PCs, even key files.
What is the best way to connect to the server and change the password?

Answer 1

Theoretically, you can reduce the number of unnecessary entities if you pass the entire command in one line.
Something like this (slash passwords):

ssh [email protected] 'echo -e "password\npassword" | passwd username

Answer 2

Some wild shit...

$connection = ssh2_connect($server_host, 22);
if(ssh2_auth_password($connection, $login, $password)){
        $stdio = ssh2_exec($connection, $command);
        stream_set_blocking($stdio, 1);
}

Can you handle errors and write a $command?

Answer 3

You can try replacing this expect script with the sshpass utility (you will have to install it separately)
sshpass -p password ssh [email protected] "echo user1:passwd1 | chpass"
for security reasons, it is better to transfer the password through a file or an environment variable (there is such a possibility)
Well, the correct method (which was recommended above) is to generate the
ssh-keygen key
and go through all the servers (since you know the root password), and enter this key to access via ssh
cat /root/.ssh/id_rsa.pub | ssh [email protected] "cat >> /root/.ssh/authorized_keys"
after which you will go to all servers without a password

Answer 4

well, to change the password in sh scripts, I would not recommend using the passwd command
, it is better to use the chpasswd command
echo "user:password" | chpasswd