#!/usr/bin/env perl
use strict;

#
# Converts a sudoers file to LDIF format in prepration for loading into
# the LDAP server.
#

# BUGS:
#   Does not yet handle multiple lines with : in them
#   Does not yet remove quotation marks from options
#   Does not yet escape + at the beginning of a dn
#   Does not yet handle line wraps correctly
#   Does not yet handle multiple roles with same name (needs tiebreaker)
#
# CAVEATS:
#   Sudoers entries can have multiple RunAs entries that override former ones,
#	with LDAP sudoRunAs{Group,User} applies to all commands in a sudoRole

my %RA;
my %UA;
my %HA;
my %CA;
my $base=$ENV{SUDOERS_BASE} or die "$0: Container SUDOERS_BASE undefined\n";
my @options=();

my $did_defaults=0;

# parse sudoers one line at a time
while (<>){

  # remove comment
  s/#.*//;

  # line continuation
  $_.=<> while s/\\\s*$//s;

  # cleanup newline
  chomp;

  # ignore blank lines
  next if /^\s*$/;

  if (/^Defaults\s+/i) {
    my $opt=$';
    $opt=~s/\s+$//; # remove trailing whitespace
    push @options,$opt;
  } elsif (/^(\S+)\s+(.+)=\s*(.*)/) {

    # Aliases or Definitions
    my ($p1,$p2,$p3)=($1,$2,$3);
    $p2=~s/\s+$//; # remove trailing whitespace
    $p3=~s/\s+$//; # remove trailing whitespace

    if ($p1 eq "User_Alias") {
      $UA{$p2}=$p3;
    } elsif ($p1 eq "Runas_Alias") {
      $RA{$p2}=$p3;
    } elsif ($p1 eq "Host_Alias") {
      $HA{$p2}=$p3;
    } elsif ($p1 eq "Cmnd_Alias") {
      $CA{$p2}=$p3;
    } else {
      if (!$did_defaults++){
        # do this once
        print "dn: cn=defaults,$base\n";
        print "objectClass: top\n";
        print "objectClass: sudoRole\n";
        print "cn: defaults\n";
     print "description: Default sudoOption's go here\n";
        print "sudoOption: $_\n" foreach @options;
        print "\n";
      }
      # Definition
      my @users=split /\s*,\s*/,$p1;
      my @hosts=split /\s*,\s*/,$p2;
      my @cmds= split /\s*,\s*/,$p3;
      @options=();
      print "dn: cn=$users[0],$base\n";
      print "objectClass: top\n";
      print "objectClass: sudoRole\n";
      print "cn: $users[0]\n";
      # will clobber options
      print "sudoUser: $_\n"   foreach expand(\%UA,@users);
      print "sudoHost: $_\n"   foreach expand(\%HA,@hosts);
      foreach (@cmds) {
	if (s/^\(([^\)]+)\)\s*//) {
	  my @runas = split(/:\s*/, $1);
	  if (defined($runas[0])) {
	    print "sudoRunAsUser: $_\n" foreach expand(\%RA, split(/,\s*/, $runas[0]));
	  }
	  if (defined($runas[1])) {
	    print "sudoRunAsGroup: $_\n" foreach expand(\%RA, split(/,\s*/, $runas[1]));
	  }
	}
      }
      print "sudoCommand: $_\n" foreach expand(\%CA,@cmds);
      print "sudoOption: $_\n" foreach @options;
      print "\n";
    }

  } else {
    print "parse error: $_\n";
  }

}

#
# recursively expand hash elements
sub expand{
  my $ref=shift;
  my @a=();

  # preen the line a little
  foreach (@_){
    # if NOPASSWD: directive found, mark entire entry as not requiring
    s/NOPASSWD:\s*// && push @options,"!authenticate";
    s/PASSWD:\s*// && push @options,"authenticate";
    s/NOEXEC:\s*// && push @options,"noexec";
    s/EXEC:\s*// && push @options,"!noexec";
    s/SETENV:\s*// && push @options,"setenv";
    s/NOSETENV:\s*// && push @options,"!setenv";
    s/\w+://; # silently remove other directives
    s/\s+$//; # right trim
  }

  # do the expanding
  push @a,$ref->{$_} ? expand($ref,split /\s*,\s*/,$ref->{$_}):$_ foreach @_;
  @a;
}