Change Login Page Logo

<?php
/**
 * Change the logo on the login page. Make the image no wider than 320px and no taller than 82px.
 */
function custom_login_logo() { ?>

h1 a { background: url(/custom/images/logo_login.png) 50% 50% no-repeat !important; }
<?php
}
add_action('login_head', 'custom_login_logo');

/**
 * Change where the logo on the login page links to
 */
function custom_login_headerurl($url) {
  return bloginfo('url') . '/';
}
add_filter('login_headerurl', 'custom_login_headerurl');

/**
 * Change the title attribute for the logo link on the login page
 */
function custom_login_headertitle($title) {
  return bloginfo('name');
}
add_filter('login_headertitle', 'custom_login_headertitle');