0000 #!/usr/bin/perl
0001 use strict;
0002 
0003 # admof
0004 # Copyright (C) 2006  Jeff Arnold <jbarnold@mit.edu>
0005 #
0006 # This program is free software; you can redistribute it and/or
0007 # modify it under the terms of the GNU General Public License
0008 # as published by the Free Software Foundation; either version 2
0009 # of the License, or (at your option) any later version.
0010 #
0011 # This program is distributed in the hope that it will be useful,
0012 # but WITHOUT ANY WARRANTY; without even the implied warranty of
0013 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
0014 # GNU General Public License for more details.
0015 #
0016 # You should have received a copy of the GNU General Public License
0017 # along with this program; if not, write to the Free Software
0018 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
0019 #
0020 # See /COPYRIGHT in this repository for more information.
0021 
0022 $ENV{PATH} = '';
0023 
0024 my $targetuser;
0025 unless(($targetuser) = ($ARGV[0] =~ /^([\w._-]+)$/)) {
0026   error("Invalid locker name: <$ARGV[0]>.");
0027 }
0028 my $curuser;
0029 unless(($curuser) = ($ARGV[1] =~ /^([\w._-]+)\@ATHENA\.MIT\.EDU$/)) {
0030   error("An internal error has occurred.\nContact scripts\@mit.edu for assistance.");
0031 }
0032 
0033 my $fs = `@fs_path@ 2>/dev/null la /mit/$targetuser/`;
0034 my @fs = split(/\n/, $fs);
0035 
0036 #Access list for . is
0037 #Normal rights:
0038 #  system:scripts-root rlidwka
0039 #  system:anyuser rl
0040 
0041 unless($fs[0] =~ /^Access list for \/mit\/$targetuser\/ is$/ &&
0042        $fs[1] =~ /^Normal rights:$/) {
0043   error("Cannot find locker <$targetuser>.");
0044 }
0045 
0046 if($ARGV[2] && !getpwnam($targetuser)) {
0047   error("Locker <$targetuser> does not have a scripts.mit.edu account.");
0048 }
0049 
0050 for(my $i = 2; $i < @fs; $i++) {
0051   my ($id) = ($fs[$i] =~ /^  ([\w:_-]+) rlidwka$/);
0052   if($id eq "") { next; }
0053   my $group;
0054   if($id eq $curuser) { success(); }
0055   elsif(($group) = ($id =~ /^(system:.+)/)) {
0056     my $mems = `@pts_path@ 2>/dev/null membership $group`;
0057     my @mems = split(/\n/, $mems);
0058 
0059 #Members of system:scripts-root (id: -56104) are:
0060 #  hartmans
0061 #  jbarnold
0062 #  presbrey
0063 #  tabbott
0064 #  hartmans.root
0065 
0066     next if($mems[0] !~ /^Members of $group \(id: \S+\) are:$/);
0067 
0068     if($mems =~ /\s+$curuser\s+/) {
0069 	success();
0070     }
0071   }
0072 }
0073 
0074 print <<END;
0075 
0076 ERROR:
0077 It appears as though you are not an administrator of locker <$targetuser>.
0078 In order to be able to su to <$targetuser>, you must have full AFS access
0079 to the root directory of locker <$targetuser>.  Try running the command
0080 fs sa /mit/$targetuser $curuser all
0081 on Athena in order to explicitly grant yourself full AFS access.
0082 Contact scripts\@mit.edu if you are unable to solve the problem.
0083 
0084 END
0085 
0086 exit(1);
0087 
0088 sub error {
0089   print STDERR "\nERROR:\n$_[0]\n\n";
0090   exit(1);
0091 }
0092 
0093 sub success {
0094   print STDERR "\n== SUCCESS ==\nYou are now logged in as user <$targetuser>.\n";
0095   print STDERR "To return to being <$curuser>, type \"exit\".\n\n";
0096   exit(33);
0097 }