使用phpseclib解析“passwd”命令

Question

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

    $new_user_pw

    $new_user_pw
 
"); 
$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

Answer 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
");
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
");
$ssh->read('password:');
$ssh->write("newpw
");
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
");
$ssh->read('password:');
$ssh->write("newpw
");
$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.