PHP - Generar password automaticament

$passwordn = md5(uniqid(mt_rand(), true));

$passwordn = substr($passwordn, 0, 10);

$passwordn = password_hash(uniqid(mt_rand(), true), PASSWORD_DEFAULT);

$pass = 'eda2014';

	// Protegemos la contraseña...

	$passHash = password_hash($pass, PASSWORD_DEFAULT);

<?php

function generar_pass_aleatorio($longitud){

  $semilla   = array();

  $semilla[] = array('a','e','i','o','u');

  $semilla[] = array('b','c','d','f','g','h','j','k','l','m','n','p','q','r','s','t','v','w','x','y','z');

  $semilla[] = array('0','1','2','3','4','5','6','7','8','9');

  $semilla[] = array('A','E','I','O','U');

  $semilla[] = array('B','C','D','F','G','H','J','K','L','M','N','P','Q','R','S','T','V','W','X','Y','Z');

  $pass = '';

  for ($bucle = 0; $bucle < $longitud; $bucle++) {

    $valor    = mt_rand(0, count($semilla) - 1);

    $posicion = mt_rand(0, count($semilla[$valor]) - 1);

    $pass .= $semilla[$valor][$posicion];

  }

  return $pass;

}

// [8] correspode a la longitud que quieras darle

$pass = generar_pass_aleatorio(8, false);

echo '<h2>El $pass es:  '.$pass.'</h2>';

	// Protegemos la contraseña...

	$passHash = password_hash($pass, PASSWORD_DEFAULT);

echo '<h2>El $passHash es:  '.$passHash.'</h2>';

?>