Using shell_exec('passwd') to change a user's password

Question

I need to be able to change the users' password through a web page (in a controlled environment). So, for that, I'm using this code:

<?php
$output = shell_exec("sudo -u dummy passwd testUser testUserPassword");
$output2 = shell_exec("dummyPassword");
echo $output;
echo $output2;
echo "done";
?>

My problem is that this script is not changing the password for the user "testUser". What am I doing wrong?

Thanks

Answer 1

Another option is to have a shell script, say called passwd_change.sh somewhere that looks like this:

#!/usr/bin/expect -f
set username [lindex $argv 0]
set password [lindex $argv 1]

spawn passwd $username
expect "(current) UNIX password: " 
send "$password\r"
expect "Enter new UNIX password: "
send "$password\r"
expect "Retype new UNIX password: "
send "$password\r"
expect eof

Then in your php code do:

<?php
shell_exec("sudo -u root /path/to/passwd_change.sh testUser testUserPass");
?>