Title: Password generation
Submitter: Alan Prescott (other recipes)
Last Updated: 2002/11/29
Version no: 1.0
Category: Security Solutions

Description:

Improved version of make_password submitted by Shane Caraveo. This one adds options to use upper case characters, numerics and special characters.

Source: Text Source

function make_password($length,$strength=0) {
  $vowels = 'aeiouy';
  $consonants = 'bdghjlmnpqrstvwxz';
  if ($strength & 1) {
    $consonants .= 'BDGHJLMNPQRSTVWXZ';
  }
  if ($strength & 2) {
    $vowels .= "AEIOUY";
  }
  if ($strength & 4) {
    $consonants .= '0123456789';
  }
  if ($strength & 8) {
    $consonants .= '@#$%^';
  }
  $password = '';
  $alt = time() % 2;
  srand(time());
  for ($i = 0; $i < $length; $i++) {
    if ($alt == 1) {
      $password .= $consonants[(rand() % strlen($consonants))];
      $alt = 0;
    } else {
        $password .= $vowels[(rand() % strlen($vowels))];
      $alt = 1;
    }
  }
  return $password;
}

Discussion:

After seeing the comments regarding password security I amended Shane's original code to include a strength option. This is a bit mask of the various options: 1 adds in upper case consonants, 2 adds in upper case vowels, 4 adds in numbers and 8 adds in special characters.
make_password(8,3); would geberate an 8 character password with upper and lower consonants and vowels.
make_password(8,5); would generate an 8 character password with upper case consonants and numbers.
It can still generate a valid dictionary entry at random (unless numbers and special characters are included)