[CR]eate [USER] -> cruser

Tool to create users on Linux system.

Mechanism of users creation are inspired by Google Cloud, when username are automatically taken from SSH-key(and email after).

List of users are need to be provided in the authorized_keys file format.

Requirements

Tool don't use any external libraries, but relies on some default(in most Linux distros) CLI tools:

• id - used to check, if user exist in the system, get user's gid and uid
• useradd - used for user creation
• visudo - used for validation of sudoers lines

Example:

• File users:

ssh-rsa aaaaaaaaaaaaaaaaaaaaaa test@gmail.com
ssh-rsa bbbbbbbbbbbbbbbbbbbbbb test@gmail.com
ssh-rsa cccccccccccccccccccccc hello@gmail.com
ssh-rsa cccccccccccccccccccccc hello@gmail.com

• Result of running command cruser -file users will be:
  • Created users test and hello
  • Sudoers lines are generated and validated with visudo
  • Line test ALL=(ALL) NOPASSWD:ALL added to the file /etc/sudoers.d/test
  • Line hello ALL=(ALL) NOPASSWD:ALL added to the file /etc/sudoers.d/hello
  • Provided SSH keys are added to the /home/test/.ssh/authorized_keys and /home/hello/.ssh/authorized_keys
  • Duplicated lines are skipped
  • test@gmail.com and hello@gmail.com are added as comment entry in the /etc/password file

Build:

make build

Running demo:

make demo

Missing features:

• Adding SSH-keys for existing users. Currently only newly created users supported
• Reading SSH-keys list form remote location(S3, github, etc)
• More flexible Sudoers configuration(only NOPASSWD:ALL are supported now)