Linux – Changing user password through GUI app

guilinuxpasswd

I was making a GUI application to manage users and groups in Linux!

I'm done with the part where it creates a new user, but stuck with the part where it gives the newly created user a new password.
What my app simply does is to take the required input (username, list of groups, and password) through a GUI and runs a script passing this info as argument.
Let's say we have a user account, xyz.
If I want to change the password for this account, then all I need to do is simply run the command:

passwd xyz

This will ask for new password. Now I can create a new account using scripts because all the required info is passed in the command line.

useradd -m -G users -g "groups" -s /bin/bash "UserName"

I can run a script through Qt app and create the user, but
in passwd cmd, the input is asked in the other line. How does one deal with that?

Best Answer

I think the right answer here is: don't shell to a command-line tool — use a library call. This will let you handle errors better, and avoids risk-prone passing of the password on a command line.

One library you can use is libuser, which is relatively simple and has C and Python bindings.

Related Solutions

Linux – How to set the password of a new user after the account has already been created

Easiest way to do this from the command line is to use the passwd command with root privileges.

passwd username

From man 1 passwd

NAME
       passwd - update user's authentication token
SYNOPSIS
       passwd  [-k]  [-l]  [-u [-f]] [-d] [-n mindays] [-x maxdays]
       [-w warndays] [-i inactivedays] [-S] [--stdin] [username]
DESCRIPTION
       The passwd utility is used to update user's authentication token(s).

After you set the user password, you can force the user to change it on next login using the chage command (also with root privileges) which expires the password.

chage -d 0 username

When the user successfully authenticates with the password you set, the user will automatically be prompted to change it. After a successful password change, the user will be disconnected, forcing re-authentication with the new password.

See man 1 chage for more information on password expiry.

Debian – Clone Linux user (copy user, based on another one)

This script will do it (updated as per comments):

#!/bin/bash
SRC=$1
DEST=$2

SRC_GROUPS=$(id -Gn ${SRC} | sed "s/ /,/g" | sed -r 's/\<'${SRC}'\>\b,?//g')
SRC_SHELL=$(awk -F : -v name=${SRC} '(name == $1) { print $7 }' /etc/passwd)

sudo useradd --groups ${SRC_GROUPS} --shell ${SRC_SHELL} --create-home ${DEST}
sudo passwd ${DEST}

It gets the source user's groups (not including the group that's the same as their login) and shell, then creates a new user with the same shell and secondary groups.

Usage: clone-user src_user_name new_user_name

There is no error checking, it's just a quick and dirty clone script.

Best Answer

Related Solutions

Linux – How to set the password of a new user after the account has already been created

Debian – Clone Linux user (copy user, based on another one)

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