School assignment

useradd.pl

#!/usr/bin/perl
#
# Program for adding one user.
#
# Need to have username as input, rest is suggested by program.
# Output is a user in the *nix system.

# Print program start.
print "Add new user\n";

# Subroutine for printing title, suggestion and taking input.
sub subr {
  ($text,$suggestion)=(@_);
  print "$text [$suggestion]: ";
  chomp($temp=<STDIN>);
  if(!$temp) { $temp = $suggestion; }
  return $temp;
}

# Randomize password.
@chars = ('a'..'z','A'..'Z','0'..'9');
$chalen = scalar(@chars);
# Length of password, between 8 and 20.
$passlen = (int(rand 12)+8);
# Seed the random.
srand;
# Go through $passlen times and add a random char each time.
for (0..$passlen) {
  $_rand = int(rand $chalen);
  $randpass .= $chars[$_rand];
}

# Subroutines with titles and suggestions.
while (!$user) { $user = subr("Username", ""); }
$pass = subr("Password", $randpass);
$uid  = subr("UID (negative values use system's suggestion)", "-1");
$homedir = "/home/$user";
$hod  = subr("Home directory", $homedir);
$skel = subr("Initialize home from skeleton", "y");
$com  = subr("Comment on user", "");
$groups = "users,audio,video,games";
$grp  = subr("Group list (comma separated, first one is initial group)", $groups);
$shl  = subr("Shell", "/bin/bash");

# Controls.
int($uid);

# Format comment correctly.
if ($com) {$comment = "-c \"$com\" ";} else { $comment = ""; }
# Set skel.
if ($skel =~ /y/) {$skel = "-m";} else {$skel = "";}
# Format UID
if ($uid < "0") {$uid = "";} else {$uid = "-u $uid";}

# Get primary group.
@grps = split(",", $grp);
$primary = shift(@grps);
# If user only writes one group
unless (scalar(@grps) == 0) {
  $secgroups = join(",", @grps);
  $secgroups = "-G $secgroups";
} else {
  $secgroups = "";
}

$command = "useradd -p $pass -d $hod $skel $uid $comment-g $primary $secgroups -s $shl $user";

print "\n$command\n";
print "Is this OK? [y/N] ";
chomp($confirm=<STDIN>);

if($confirm !~ /y/) { 
  print "Aborting.\n"; 
  exit; 
}

system($command);