#!/usr/bin/perl

# deluser -- a utility to remove users from the system
# delgroup -- a utilty to remove groups from the system
my $version = "3.112+nmu2";

# Copyright (C) 2000 Roland Bauerschmidt <rb@debian.org>
# Based on 'adduser' as pattern by
#     Guy Maor <maor@debian.org>
#     Ted Hajek <tedhajek@boombox.micro.umn.edu>
#     Ian A. Murdock <imurdock@gnu.ai.mit.edu>

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

####################
# See the usage subroutine for explanation about how the program can be called
####################

use warnings;
use strict;
use Getopt::Long;
use Debian::AdduserCommon;

my $install_more_packages ;

BEGIN {
    local $ENV{PERL_DL_NONLAZY}=1;
    eval 'use File::Find';
    if ($@) {
      $install_more_packages = 1;
    }
    #no warnings "File::Find";
    eval 'use File::Temp';
    if ($@) {
      $install_more_packages = 1;
    }
}


BEGIN {
    eval 'use Locale::gettext';
    if ($@) {
        *gettext = sub { shift };
        *textdomain = sub { "" };
        *LC_MESSAGES = sub { 5 };
    }
    eval {
        require POSIX;
        import POSIX qw(setlocale);
    };
    if ($@) {
        *setlocale = sub { return 1 };
    }
}

setlocale(LC_MESSAGES, "");
textdomain("adduser");

my $action = $0 =~ /delgroup$/ ? "delgroup" : "deluser";
our $verbose = 1;
my %pconfig = ();
my %config = ();
my $configfile;
my @defaults;
my $force;


unless ( GetOptions ("quiet|q" => sub {$verbose = 0; },
            "debug" => sub {$verbose = 2; },
	    "version|v" => sub { &version(); exit 0; },
	    "help|h" => sub { &usage(); exit 0;},
	    "group" => sub { $action = "delgroup";},
	    "conf=s" => \$configfile,
	    "system" => \$pconfig{"system"},
	    "only-if-empty" => \$pconfig{"only_if_empty"},
	    "remove-home" => \$pconfig{"remove_home"},
	    "remove-all-files" => \$pconfig{"remove_all_files"},
	    "backup" => \$pconfig{"backup"},
	    "backup-to=s" => \$pconfig{"backup_to"},
            "force" => \$force
       ) ) {
    &usage;
    exit 1;
}

# everyone can issue "--help" and "--version", but only root can go on
dief (gtx("Only root may remove a user or group from the system.\n")) if ($> != 0);

if (!defined($configfile)) { 
    @defaults = ("/etc/adduser.conf", "/etc/deluser.conf");
} else {
    @defaults = ($configfile);
}

# explicitly set PATH, because super (1) cleans up the path and makes deluser unusable;
# this is also a good idea for sudo (which doesn't clean up)
$ENV{"PATH"}="/bin:/usr/bin:/sbin:/usr/sbin";

my @names = ();
my ($user,$group);

######################
# handling of @names #
######################

while (defined(my $arg = shift(@ARGV))) {
  if (defined($names[0]) && $arg =~ /^--/) {
      dief (gtx("No options allowed after names.\n"));
    } else {			# it's a username
	push (@names, $arg);
    }
}

if(@names == 0) {
    if($action eq "delgroup") {
	print (gtx("Enter a group name to remove: "));
    } else {
	print (gtx("Enter a user name to remove: "));
    }
    chomp(my $answer=<STDIN>);
    push(@names, $answer);
}

if (length($names[0]) == 0 || @names > 2) {
    dief (gtx("Only one or two names allowed.\n"));
}

if(@names == 2) {      # must be deluserfromgroup
    $action = "deluserfromgroup";
    $user = shift(@names);
    $group = shift(@names);
} else {
    if($action eq "delgroup") {
	$group = shift(@names);
    } else {
	$user = shift(@names);
    }
}

undef(@names);


##########################################################
# (1) preseed the config
# (2) read the default /etc/adduser.conf configuration.
# (3) read the default /etc/deluser.conf configuration.
# (4) process commmand line settings
# last match wins
##########################################################

preseed_config (\@defaults,\%config);

foreach(keys(%pconfig)) {
    $config{$_} = $pconfig{$_} if ($pconfig{$_});
}

if (($config{remove_home} || $config{remove_all_files} || $config{backup}) && ($install_more_packages)) {
    fail (8, gtx("In order to use the --remove-home, --remove-all-files, and --backup features,
you need to install the `perl-modules' package. To accomplish that, run
apt-get install perl-modules.\n"));
}

 
my ($pw_uid, $pw_gid, $pw_homedir, $gr_gid, $maingroup);

if($user) {
    my @passwd = getpwnam($user);
    $pw_uid = $passwd[2];
    $pw_gid = $passwd[3];
    $pw_homedir = $passwd[7];
    
    $maingroup = $pw_gid ? getgrgid($pw_gid) : "";
}
if($group) {
    #($gr_name,$gr_passwd,$gr_gid,$gr_members) = getgrnam($group);
    my @group = getgrnam($group);
    $gr_gid = $group[2];
}

# arguments are processed:
#
#  $action = "deluser"
#     $user          name of the user to remove
#
#  $action = "delgroup"
#     $group         name of the group to remove
#
#  $action = "deluserfromgroup"
#     $user          the user to be remove
#     $group         the group to remove him/her from


if($action eq "deluser") {
    &invalidate_nscd();
    
    my($dummy1,$dummy2,$uid);



    # Don't allow a non-system user to be deleted when --system is given
    # Also, "user does not exist" is only a warning with --system, but an
    # error without --system.
    if( $config{"system"} ) {
	if( ($dummy1,$dummy2,$uid) = getpwnam($user) ) {
	    if ( ($uid < $config{"first_system_uid"} ||
		$uid > $config{"last_system_uid" } ) ) {
		printf (gtx("The user `%s' is not a system user. Exiting.\n"), $user) if $verbose;
		exit 1;
	    }
        } else {
	    printf (gtx("The user `%s' does not exist, but --system was given. Exiting.\n"), $user) if $verbose;
	    exit 0;
	}
    }
    
    unless(exist_user($user)) {
	fail (2,gtx("The user `%s' does not exist.\n"),$user);
    }
    
    # Warn in any case if you want to remove the root account 
    if ((defined($pw_uid)) && ($pw_uid == 0) && (!defined($force)))  {
        printf (gtx("WARNING: You are just about to delete the root account (uid 0)\n"));
        printf (gtx("Usually this is never required as it may render the whole system unusable\n"));
        printf (gtx("If you really want this, call deluser with parameter --force\n"));
        printf (gtx("Stopping now without having performed any action\n"));
        exit 9;
    }

    # consistency check
    # if --backup-to is specified, --backup should be set too
    if ($pconfig{"backup_to"}) {
        $config{"backup"} = 1;
    }

    if($config{"remove_home"} || $config{"remove_all_files"}) {
      s_print (gtx("Looking for files to backup/remove ...\n"));
      my @mountpoints;
      open(MOUNT, "mount |")
	      || fail (4 ,gtx("fork for `mount' to parse mount points failed: %s\n", $!));
      while (<MOUNT>) {
	      my @temparray = split;
	      my $fstype = $temparray[4];
	      my $exclude_fstypes = $config{"exclude_fstypes"};
	      if (defined($exclude_fstypes)) {
	      	next if ($fstype =~ /$exclude_fstypes/);
	      }
	      push @mountpoints,$temparray[2];
      }
      close(MOUNT) or dief (gtx("pipe of command `mount' could not be closed: %s\n",$!));
      my(@files,@dirs);
      if($config{"remove_home"} && ! $config{"remove_all_files"}) {

        # collect all files in user home
	sub home_match {
	  # according to the manpage
	  foreach my $mount (@mountpoints) {
	    if( $File::Find::name eq $mount ) {
	      s_printf (gtx("Not backing up/removing `%s', it is a mount point.\n"),$File::Find::name);
	      $File::Find::prune=1;
	      return;
	    }
	  }
	  foreach my $re ( split ' ', $config{"no_del_paths"} ) {
	    if( $File::Find::name =~ qr/$re/ ) {
	      s_printf (gtx("Not backing up/removing `%s', it matches %s.\n"),$File::Find::name,$re);
	      $File::Find::prune=1;
	      return;
	    }
	  }

	  push(@files, $File::Find::name) 
	    if(-f $File::Find::name || -l $File::Find::name);
	  push(@dirs, $File::Find::name)
	    if(-d $File::Find::name);
	} # sub home_match
	
	File::Find::find({wanted => \&home_match, untaint => 1, no_chdir => 1}, $pw_homedir)
	  if(-d "$pw_homedir");
	push(@files, "/var/mail/$user")
	  if(-e "/var/mail/$user");
      } else {

        # collect all files on system belonging to that user
	sub find_match {
	  my ($dev,$ino,$mode,$nlink,$uid,$gid);
	  (($dev,$ino,$mode,$nlink,$uid,$gid) = lstat($_)) &&
	    ($uid == $pw_uid) &&
	      (
		($File::Find::name =~ /^\/proc\// && ($File::Find::prune = 1)) ||
		(-f $File::Find::name && push(@files, $File::Find::name)) ||
		(-d $File::Find::name && push(@dirs, $File::Find::name)) ||
                (-l $File::Find::name && push(@dirs, $File::Find::name)) ||
                (-S $File::Find::name && push(@dirs, $File::Find::name)) || 
                (-p $File::Find::name && push(@dirs, $File::Find::name))
	      );
              if ( -b $File::Find::name || -c $File::Find::name ) {
               warnf (gtx("Cannot handle special file %s\n"),$File::Find::name);
              }
	} # sub find_match
	
	File::Find::find({wanted => \&find_match, untaint => 1, no_chdir => 1}, '/');
      }

      if($config{"backup"}) {
	 s_printf (gtx("Backing up files to be removed to %s ...\n"),$config{"backup_to"});
	 my $filesfile = new File::Temp(TEMPLATE=>"deluser.XXXXX", DIR=>"/tmp");
	 my $filesfilename = $filesfile->filename;
	 my $backup_name = $config{"backup_to"} . "/$user.tar";
	 print "backup_name = $backup_name";
	 print $filesfile join("\n",@files);
	 $filesfile->close();
         my $tar = &which('tar');
         my $bzip2 = &which('bzip2', 1);
         my $gzip = &which('gzip', 1);
         my $options = '';
	 if($bzip2) {
             $backup_name = "$backup_name.bz2";
             $options = "--bzip2";
	 } elsif($gzip) {
             $backup_name = "$backup_name.gz";
             $options = "--gzip";
	 }
	 &systemcall($tar, $options, "-cf", $backup_name, "--files-from", $filesfilename);
	 chmod 0600, $backup_name;
         my $rootid = 0;
	 chown $rootid, $rootid, $backup_name;
	 unlink($filesfilename);
      }

      if(@files || @dirs) {
	  s_print (gtx("Removing files ...\n"));
	  unlink(@files) if(@files);
	  foreach(reverse(sort(@dirs))) {
	      rmdir($_);
	  }
      }
    }

    if (system("crontab -l $user >/dev/null 2>&1") == 0) {
      # crontab -l returns 1 if there is no crontab
      my $crontab = &which('crontab');
      &systemcall($crontab, "-r", $user);
      s_print (gtx("Removing crontab ...\n"));
    }

    s_printf (gtx("Removing user `%s' ...\n"),$user);
    my @members = get_group_members($maingroup);
    if (@members == 0) {
        s_printf (gtx("Warning: group `%s' has no more members.\n"), $maingroup);    
    }
    my $userdel = &which('userdel');
    &systemcall($userdel, $user);
    &invalidate_nscd();

    systemcall('/usr/local/sbin/deluser.local', $user, $pw_uid,
                $pw_gid, $pw_homedir) if (-x "/usr/local/sbin/deluser.local");

    s_print (gtx("Done.\n"));
    exit 0;
}

    
if($action eq "delgroup") {
    &invalidate_nscd();
    unless(exist_group($group)) {
	printf( gtx("The group `%s' does not exist.\n"),$group) if $verbose;
        exit 3;
    }
    my($dummy,$gid,$members);
    if( !(($dummy, $dummy, $gid, $members ) = getgrnam($group)) ) {
	fail (4 ,gtx("getgrnam `%s' failed. This shouldn't happen.\n"), $group);
    }
    if( $config{"system"} && 
	($gid < $config{"first_system_gid"} ||
	 $gid > $config{"last_system_gid" } )) {
        printf (gtx("The group `%s' is not a system group. Exiting.\n"), $group) if $verbose;
	exit 3;
    }
    if( $config{"only_if_empty"} && $members ne "") {
	fail (5, gtx("The group `%s' is not empty!\n"),$group);
    }
    
    setpwent;
    while ((my $acctname,my $primgrp) = (getpwent)[0,3]) {
	if( $primgrp eq $gr_gid ) {
	    fail (7, gtx("`%s' still has `%s' as their primary group!\n"),$acctname,$group);
	}
    }
    endpwent;

    s_printf (gtx("Removing group `%s' ...\n"),$group);
    my $groupdel = &which('groupdel');
    &systemcall($groupdel,$group);
    &invalidate_nscd();
    s_print (gtx("Done.\n"));
    exit 0;
}


if($action eq "deluserfromgroup")
{
    &invalidate_nscd();
    unless(exist_user($user)) {
	fail (2, gtx("The user `%s' does not exist.\n"),$user);
    }
    unless(exist_group($group)) {
	fail (3, gtx("The group `%s' does not exist.\n"),$group);
    }
    if($maingroup eq $group) {
	fail (7, gtx("You may not remove the user from their primary group.\n"));
    }

    my @members = get_group_members($group);
    my $ismember = 0;

    for(my $i = 0; $i <= $#members; $i++) {
	if($members[$i] eq $user) {
	    $ismember = 1;
	    splice(@members,$i,1);
	}
    }

    unless($ismember) {
	fail (6, gtx("The user `%s' is not a member of group `%s'.\n"),$user,$group);
    }

    s_printf (gtx("Removing user `%s' from group `%s' ...\n"),$user,$group);
    #systemcall("usermod","-G", join(",",@groups), $user );
    my $gpasswd = &which('gpasswd');
    &systemcall($gpasswd,'-M', join(',',@members), $group);
    &invalidate_nscd();
    s_print (gtx("Done.\n"));
}


######

sub fail {
  my ($errorcode, $format, @args) = @_;
  printf STDERR "$0: $format",@args;
  exit $errorcode;

}

sub version {
    printf (gtx("deluser version %s\n\n"), $version);
    printf (gtx("Removes users and groups from the system.\n"));
    
    printf gtx("Copyright (C) 2000 Roland Bauerschmidt <roland\@copyleft.de>\n\n");

    printf gtx("deluser is based on adduser by Guy Maor <maor\@debian.org>, Ian Murdock\n".
	  "<imurdock\@gnu.ai.mit.edu> and Ted Hajek <tedhajek\@boombox.micro.umn.edu>\n\n");

    printf gtx("This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at
your option) any later version.

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License, /usr/share/common-licenses/GPL, for more details.\n");
}

sub usage {
    printf gtx(
"deluser USER
  remove a normal user from the system
  example: deluser mike

  --remove-home             remove the users home directory and mail spool
  --remove-all-files        remove all files owned by user
  --backup                  backup files before removing.
  --backup-to <DIR>         target directory for the backups.
                            Default is the current directory.
  --system                  only remove if system user

delgroup GROUP
deluser --group GROUP
  remove a group from the system
  example: deluser --group students

  --system                  only remove if system group
  --only-if-empty           only remove if no members left

deluser USER GROUP
  remove the user from a group
  example: deluser mike students

general options:
  --quiet | -q      don't give process information to stdout
  --help | -h       usage message
  --version | -v    version number and copyright
  --conf | -c FILE  use FILE as configuration file\n\n");
}

sub exist_user {
    my $exist_user = shift;
    return(defined getpwnam($exist_user));
}

sub exist_group {
    my $exist_group = shift;
    return(defined getgrnam($exist_group));
}

# vim:set ai et sts=4 sw=4 tw=0:
