Parse “passwd” command with phpseclib

问题

I tried to parse "passwd" command to my machine with phpseclib but it can't go through the first password typing. Look at the code below.

$ssh->write("
    passwd $new_user\n
    $new_user_pw\n
    $new_user_pw\n 
"); 
$ssh->setTimeout(5);
echo $ssh->read('root@machine:~$');

Output i got is:

Last login: Tue Jun 17 12:23:01 2014 from 109.175.60.43 [root@machine ~]# [root@machine ~]# [root@machine ~]# passwd 8917f498 Changing password for user 8917f498. New password:

Or can I do this with another way?

Thanks

回答1:

If you do passwd on yourself you'll be prompted for the old pw before being allowed to set the new pw. And on my Linux system I wasn't able to do passwd on another user without doing root. That may result in you being for your prompted for your password as well.

As a general rule, the way I found out what the prompt is is by doing $ssh->setTimeout() with an empty $ssh->read() call. eg.

$ssh->enablePTY();
$ssh->exec('sudo passwd testuser');
$ssh->setTimeout(3);
echo $ssh->read();

That outputs Enter new UNIX password:. So I rewrite my program thusly:

$ssh->enablePTY();
$ssh->exec('sudo passwd testuser');
$ssh->setTimeout(3);
$ssh->read('password:');
$ssh->write("newpw\n");
echo $ssh->read();

That outputs Retype new UNIX password:. So I then revise my program accordingly:

$ssh->enablePTY();
$ssh->exec('sudo passwd testuser');
$ssh->setTimeout(3);
$ssh->read('password:');
$ssh->write("newpw\n");
$ssh->read('password:');
$ssh->write("newpw\n");
echo $ssh->read();

That outputs passwd: password updated successfully. Now that I know it works I remove the $ssh->setTimeout(3) and update the last $ssh->read() to get this:

$ssh->enablePTY();
$ssh->exec('sudo passwd testuser');
$ssh->read('password:');
$ssh->write("newpw\n");
$ssh->read('password:');
$ssh->write("newpw\n");
$ssh->read('passwd:');

And that's it! It'll change the password without waiting for six seconds like your version does. That last $ssh->read() may not be necessary though. I'll let you play around with that.

回答2:

Ok, I fixed it.

This code works:

$ssh->enablePTY(); 
        $ssh->exec('passwd $new_user'); 
        echo $ssh->read('password:'); 
        $ssh->write("$new_pw\n"); 
        $ssh->setTimeout(3); 
        $ssh->write("$new_pw\n"); 
        $ssh->setTimeout(3); 
        echo $ssh->read('password changed');

回答3:

Using a single liner is a better option. I prefer using this:

$username = 'root';
$password = 'myReallySecurePassword';
$ssh->exec(sprintf('echo "%s" | sudo passwd --stdin %s', $password, $username));

Above will work on most modern Linux distros. If you aren't able to change the password somehow and running an older Linux distro, try this:

$username = 'root';
$password = 'myReallySecurePassword';
$ssh->exec(sprintf('echo -e "%s\n%s" | passwd %s', $password, $password, $username));

来源：https://stackoverflow.com/questions/24269189/parse-passwd-command-with-phpseclib

标签

php

Linux

ssh

phpseclib

libssh