Change linux password with Ansible playbook script when connecting as a non-root user without sudo privileges

Question

I am trying to change password for a non-root Linux user from Ansible playbook. To do so I tried to follow this link

Following the instruction I can successfully change the password of a non-root user by typing the code below in the terminal.

$ echo -e "your_current_pass\nlinuxpassword\nlinuxpassword" | passwd
Changing password for testuser.
(current) UNIX password: Enter new UNIX password: Retype new UNIX password: passwd: password updated successfully

After that I am trying to automate the code with an Ansible playbook like below,

---
- hosts: all
  gather_facts: no

  tasks:
    - name: "Check if user exists"
      register: user1_exists
      raw: getent passwd {{ ansible_user }}
      ignore_errors: true

    - name: "Change {{ ansible_user }} password"
      raw: echo -e "my_current_pass\nmy_new_pass\nmy_new_pass" | passwd
      when: user1_exists|success

I am using the raw module of Ansible here as most of my machines don't have Python installed. I do not have superuser (sudo) permission either to use become: True in playbook.

Also using password based authentication here to run the Ansible playbook on target machine. Not ssh based authentication.

But while I am executing the playbook I am getting this error,

TASK [change user1 password] ***************************************************
fatal: [192.168.0.57]: FAILED! => {"changed": true, "failed": true, "rc": 10, 
"stderr": "Shared connection to 192.168.0.57 closed.\r\n", "stdout": "Changing 
password for testuser.\r\n(current) UNIX password: passwd: Authentication 
token manipulation error\r\npasswd: password unchanged\r\n", "stdout_lines": 
["Changing password for testuser.", "(current) UNIX password: passwd: 
Authentication token manipulation error", "passwd: password unchanged"]}

Could anyone show me the mistakes I am making here?

Solution 1

Use the built-in user module instead of a shell command. This requires become: True in your playbook. Note that the password parameter of the user module requires an encrypted value. The password_hash jinja filter will help you there.

  - name: change user's password
    user:
      name: foo
      password: "{{ 'passwordsaresecret' | password_hash('sha512') }}"

Solution 2

Your playbook is almost correct. I had the same kind of requirement and I used your playbook. There was just one mistake in your playbook, you forgot to enclose your password variables in '{{}}' braces. So I changed your playbook like below and it worked for me.

  hosts: all
  gather_facts: no

  tasks:
    - name: "Check if user exists"
      register: user1_exists
      raw: getent passwd {{ ansible_user }}
      ignore_errors: true

    - name: "Change {{ ansible_user }} password"
      raw: echo -e "{{ ansible_password }}\n{{newpwd}}\n{{newpwd}}" | passwd
      when: user1_exists|success