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in reply to Re: getcwd() as different user
in thread getcwd() as different user

Oh grief, I misinterpreted the error to be the result of the "$<" operation. The actual problem is the fact that my now lesser-privileged user is not authorised to perform the next "$< = $> = $newid" iteration.

Hmm, my question should actually read: "How do I perform seteid()" or "How do I temporarily drop my privileges before calling a function? ". The obvious answer is $>. *hides in shame*

-0xbeef

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Re^3: getcwd() as different user
by 0xbeef (Hermit) on Nov 19, 2005 at 12:53 UTC
    If anyone's interested, here's a snippet with the basic working logic. Although the "id -G" portion is not the safest way of doing this, I just don't know how:

    my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime,
+$blksize,$blocks) = stat($targetdir);
$newuser =  getpwuid($uid);
$groups =  `/usr/bin/id -G $newuser`;
$) = "$groups";
$> = $uid;
if ( not chdir("$targetdir")) {
  print "$targetdir is inaccessible to its owner\n";
  next;
} else {
  $currentdir = Cwd::getcwd();
  my $lasterr = $!;
  if (not defined $currentdir) {
    # incorrect underlying mount-point permissions
    print "getcwd() failed for $targetdir:$lasterr\n";
  } else {
    print "getcwd() for $over is OK.");
  }
}

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