modules/userprotect/userprotect.module

<?php

// $Id: userprotect.module,v 1.51 2009/11/03 00:58:07 thehunmonkgroup Exp $

/**
 * Implement hook_help().
 *
 * Returns various help texts.
 */
function userprotect_help($path, $arg) {
	switch ($path) {
		case 'admin/config/people/userprotect':
		case 'admin/config/people/userprotect/protected_users':
		  $output = t('These settings override any <a href="!protected_roles">role-based protections</a> for the user in question. For more information on how to configure userprotect settings, see the <a href="!help">help section</a>.', array('!help' => url('admin/help/userprotect'), '!protected_roles' => url('admin/config/people/userprotect/protected_roles')));
			return $output;
	  case 'admin/config/people/userprotect/protected_roles':
		  $output = t('These settings add protections to any user who is in the specified role. They are overridden by any <a href="!protected_users">per-user protections</a> for the user in question. For more information on how to configure userprotect settings, see the <a href="!help">help section</a>.', array('!help' => url('admin/help/userprotect'), '!protected_users' => url('admin/config/people/userprotect/protected_users')));
			return $output;
		case 'admin/config/people/userprotect/administrator_bypass':
		  $output = t('These settings add bypasses to any user who has the \'administer users\' permission. They override the <a href="!protection_defaults">defaults</a> for the user in question. For more information on how to configure userprotect settings, see the <a href="!help">help section</a>.', array('!help' => url('admin/help/userprotect'), '!protection_defaults' => url('admin/config/people/userprotect/protection_defaults')));
			return $output;
	  case 'admin/config/people/userprotect/protection_defaults':
		  $output = t('Set global default protection values here. For more information on how to configure userprotect settings, see the <a href="!help">help section</a>.', array('!help' => url('admin/help/userprotect')));
			return $output;
	  case 'admin/help#userprotect':

		  $output = t('<p>This module provides various editing protection for users.
The protections can be specific to a user, or applied to all users in a role.
The following protections are supported:</p>
<ul>
  <li>username</li>
  <li>e-mail address</li>
  <li>password</li>
  <li>status changes</li>
  <li>roles</li>
  <li>cancellation</li>
  <li>OpenID identities (both adding and deleting)</li>
  <li>all edits (any accessed via user/X/edit)</li>
</ul>

<p>When a protection is enabled for a specified user (or the protection is
enabled because the user belongs to a role that has the protection), it
prevents the editing operation in question that anyone might try to perform
on the user -- unless an administrator who is permitted to bypass the protection
is editing the specified user.  The module will protect fields by disabling
them at user/X/edit.<p>

<p>User administrators may be configured to bypass specified protections, on either
a global or per-administrator basis.</p>

<p>These protections are valid both when trying to edit the user directly from their
user/X/edit page, or using the <a href="!admin_people">mass user editing
operations</a>.</p>

<p>The module also provides protection at the paths user/X/edit and user/X/cancel,
should anyone try to visit those paths directly.</p>

<p><em>Note: this module is compatible with the <a href="!roleassign">
RoleAssign</a> module.</em></p>

<h4>SETTINGS:</h4>

<p>At the <a href="!userprotect_settings">User Protect settings page</a>,
you\'ll find the settings for the module. When the module is initially enabled,
the default settings are such:</p>

<ul>
  <li>User administrators bypass all protections.</li>
  <li>The root user specifically bypasses all protections.</li>
  <li>The anonymous user (uid 0) and root user (uid 1) are protected
       from all edits, cancellation, and OpenID operations.</li>
  <li>All role protections are disabled.</li>
  <li>The \'change own e-mail\', \'change own password\' and \change own openid\'
      permissions are enabled for authenticated users in the <a href="!permissions">
      User Protect permissions settings</a>.
</ul>

<p>This effectively amounts to no protections.  It is suggested that you turn off
as many default administrator bypass settings as possible, and set bypass settings
for specific user administrators -- this allows you to take advantage
of the status, roles, cancellation, openid and edit protections in a meaningful
way. Because of the per-user bypass/protection settings for the anonymous and
root user, this will also begin protecting those users, without compromising
the root user\'s access to the entire site.</p>

<p>Important note: In order to protect a user from cancellation (by visiting
user/X/cancel directly) and/or OpenID edits (by visiting user/X/openid
directly), you must enable the \'cancel\' and/or \'openid\' protection specifically.
Enabling \'all account edits\' does not enable these protections!</p>

<p>Also note that this module only provides protection against actions via the website
interface--operations that a module takes directly are not protected! This module
should play well with other contributed modules, but there is no guarantee that all
protections will remain intact if you install modules outside of the drupal core
installation.</p>

<h4>ADDING PROTECTIONS FOR A SINGLE USER:</h4>

<p>This is done at <a href="!protected_users">per-user protections</a>.
Any time a user is added for protection, they will initially receive the
<a href="!protection_defaults">default protections</a>.</p>


<h4>ADDING PROTECTIONS FOR ROLES:</h4>

<p>This is done at <a href="!protected_roles">role-based protections</a>.
<em>Be cautious</em> about adding protections by role, or you can lock out users
from things unintentionally!</p>

<p>In particular, note the if you enable role protections for a specific role, and
you have no bypasses enabled, you\'ve effectively locked out any role editing for
that role by anybody, unless you come back to the settings page and disable the role
protection!</p>

<h4>ADDING ADMINISTRATOR BYPASS RULES:</h4>

<p>One of the more powerful features of the module is administrator bypass
Any user that has been granted the \'administer users\' permission can
be configured to bypass any protection, either via the
<a href="!protection_defaults">default administrator bypass settings</a>,
or via a <a href="!administrator_bypass">per-administrator setting</a>.
If a bypass is enabled for a user administrator, they will be given editing rights
on that protection regardless if it is enabled for a single user or an entire role.</p>

<p>Note that the per-administrator bypass settings override the default bypass
settings.</p>

<h4>DEFAULT PROTECTION SETTINGS:</h4>

<p>Set the <a href="!protection_defaults">default protections</a> for newly protected users.
In addition, you can enable the auto-protect feature, which will automatically
add the default protections to any newly created user accounts, and set default
bypass options for all user administrators.</p>


<h4>HOW THE MODULE DETERMINES A PROTECTION:</h4>

<p>In order to properly use User Protect, it\'s important to understand how the
module determines if a specified field is to be protected.  Here is the basic
logic:</p>
<ol>
  <li>If the current user is a user administrator, check if they have
  per-administrator bypass settings.  If so, then check to see if they are allowed
  to bypass the protection.  If so, then stop the checks and allow editing
  of the field.</li>
  <li>If not, then if the current user is a user administrator, check if the
  default administrator bypass is enabled for the protection in question. If
  so, then stop the checks and allow editing of the field.
  <li>If not, check if the user is editing their own account.  If so, determine
  the protections for e-mail, password, and openid by examining the userprotect permissions
  for \'change own e-mail\', \'change own password\' and \'change own openid\',
  then continue with the rest of the checks below.
  <li>If not, check if the protection is set for the individual user being edited.
  If so, then stop the checks here, and prevent editing of the field (this effectively
  means that individual protections override role protections).</li>
  <li>If not, then examine all the roles for the user being edited.  If any of
  those roles have the protection enabled, then prevent editing of the field.</li>
  <li>If not, then allow the field to be edited.</li>
</ol>
</p>', array('!admin_people' => url('admin/people'), '!userprotect_settings' => url('admin/config/people/userprotect/protected_users'), '!protected_users' => url('admin/config/people/userprotect/protected_users'), '!protected_roles' => url('admin/config/people/userprotect/protected_roles'), '!administrator_bypass' => url('admin/config/people/userprotect/administrator_bypass'), '!protection_defaults' => url('admin/config/people/userprotect/protection_defaults'), '!roleassign' => url('http://drupal.org/project/roleassign', array('attributes' => array('target' => 'X'), 'absolute' => TRUE)), '!permissions' => url('admin/config/people/permissions', array('fragment' => 'module-userprotect'))));
			return $output;
	}
}

/**
 * Implement hook_form_alter().
 */
function userprotect_form_alter(&$form, &$form_state, $form_id) {

  switch ($form_id) {

    // These are complex cases, and are best handled by manipulating the form values
    // in a custom validate function.
    case 'user_admin_account':
    case 'user_multiple_cancel_confirm':
      // Ensure an array.
      $form['#validate'] = isset($form['#validate']) ? $form['#validate'] : array();
      array_unshift($form['#validate'], 'userprotect_user_admin_account_validate');
      break;
    case 'openid_user_add':
    case 'openid_user_delete_form':
      $account = user_load(arg(1));
      $protected = array();
      if (!userprotect_check_bypass('up_openid') && userprotect_get_user_protection($account, 'up_openid')) {
        switch ($form_id) {
          case 'openid_user_add':
            if (isset($form['openid_identifier'])) {
              $form['openid_identifier']['#disabled'] = TRUE;
              $form['submit']['#disabled'] = TRUE;
            }
            break;
          case 'openid_user_delete_form':
            if (isset($form['actions']['submit'])) {
              $form['actions']['submit']['#disabled'] = TRUE;
              $form['confirm']['#value'] = 0;
            }
            break;
        }
        $protected['up_openid'] = TRUE;
      }
      userprotect_form_display_protections($account, $protected);
      break;
  }
}


/**
 * Implement hook_form_user_profile_form_alter().
 */
function userprotect_form_user_profile_form_alter(&$form, &$form_state) {

  // For each of the fields, first check if any of the user's roles are protecting
  // it, then check if the user themselves is protected from it.  if either is TRUE,
  // then disable the field, and mark a fixed form value so it will be properly submitted.
  $account = user_load(arg(1));
  $protected = array();
  if (isset($form['account']['name']) && !userprotect_check_bypass('up_name') && userprotect_get_user_protection($account, 'up_name')) {
    // If for some reason this field has no initial value, then don't protect it.
    if ($account->name) {
      $form['account']['name']['#disabled'] = TRUE;
      $form['account']['name']['#value'] = $account->name;
      $protected['up_name'] = TRUE;
    }
  }
  if (isset($form['account']['mail']) && !userprotect_check_bypass('up_mail') && userprotect_get_user_protection($account, 'up_mail')) {
    // If for some reason this field has no initial value, then don't protect it.
    if ($account->mail) {
      $form['account']['mail']['#disabled'] = TRUE;
      $form['account']['mail']['#value'] = $account->mail;
      $protected['up_mail'] = TRUE;
    }
  }
  // Password is an exception, as it needs no value, Just unset it, as
  // there's no need to display two empty boxes that are disabled.
  if (isset($form['account']['pass']) && !userprotect_check_bypass('up_pass') && userprotect_get_user_protection($account, 'up_pass')) {
    unset($form['account']['pass']);
    $protected['up_pass'] = TRUE;
  }
  if (isset($form['account']['status']) && !userprotect_check_bypass('up_status') && userprotect_get_user_protection($account, 'up_status')) {
    $form['account']['status']['#disabled'] = TRUE;
    $form['account']['status']['#value'] = $account->status;
    $protected['up_status'] = TRUE;
  }
  // Special hack for RoleAssign module compatibility.
  if (isset($form['account']['roleassign_roles'])) {
    $roles = 'roleassign_roles';
  }
  else {
    $roles = 'roles';
  }
  // Roles is a special case, since it's a tree'd item that needs values.
  // We'll handle that in a custom validation function. Also here we slip
  // the user's account info into the form so it's available to gleen the role
  // info from.
  if (isset($form['account'][$roles]) && !userprotect_check_bypass('up_roles') && userprotect_get_user_protection($account, 'up_roles')) {
    $form['account'][$roles]['#disabled'] = TRUE;
    // Ensure an array.
    $form['account'][$roles]['#element_validate'] = isset($form['account'][$roles]['#element_validate']) ? $form['account'][$roles]['#element_validate'] : array();
    array_unshift($form['account'][$roles]['#element_validate'], 'userprotect_user_edit_fields_validate');
    $form_state['userprotect']['account'] = $account;
    $form_state['userprotect']['field'] = 'roles';
    $protected['up_roles'] = TRUE;
  }

  // At this point, we only need the userprotect-specific validation if the
  // current user and the edited user are not the same.
  if (isset($form['cancel']) && ($GLOBALS['user']->uid != $account->uid)) {
    // Nothing special for cancel--just disable.
    if (!userprotect_check_bypass('up_cancel') && userprotect_get_user_protection($account, 'up_cancel')) {
      $form['cancel']['#disabled'] = TRUE;
      $protected['up_cancel'] = TRUE;
    }
  }
  userprotect_form_display_protections($account, $protected);
}

/**
 * Custom validation function for complex field protections.
 */
function userprotect_user_edit_fields_validate($form, &$form_state) {
  $account = $form_state['userprotect']['account'];
  $field = $form_state['userprotect']['field'];

  switch ($field) {
    case 'roles':
      // Authenticated user isn't a valid checked item.
      unset($account->roles[DRUPAL_AUTHENTICATED_RID]);
      // Add values for all role checkboxes that are valid roles for this user.
      foreach ($account->roles as $rid => $role) {
        if (isset($form[$rid])) {
          form_set_value($form[$rid], 1, $form_state);
        }
      }
      break;
  }
}

/**
 * Implement hook_menu().
 */
function userprotect_menu() {
  $items = array();
  $admin = array('administer userprotect');

  // Admin page link.
  $items['admin/config/people/userprotect'] = array(
    'title' => 'User Protect',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('userprotect_protected_users'),
    'access callback' => 'user_access',
    'access arguments' => $admin,
    'description' => t('Protect inidividual users and/or roles from editing operations.'),
  );
  // Default tab.
  $items['admin/config/people/userprotect/protected_users'] = array(
    'title' => 'Protected users',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'access callback' => 'user_access',
    'access arguments' => $admin,
    'weight' => 1,
  );
  // Protected roles tab.
  $items['admin/config/people/userprotect/protected_roles'] = array(
    'title' => 'Protected roles',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('userprotect_protected_roles'),
    'access callback' => 'user_access',
    'access arguments' => $admin,
    'type' => MENU_LOCAL_TASK,
    'weight' => 2,
  );
  // Administrator bypass tab.
  $items['admin/config/people/userprotect/administrator_bypass'] = array(
    'title' => 'Administrator bypass',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('userprotect_administrator_bypass'),
    'access callback' => 'user_access',
    'access arguments' => $admin,
    'type' => MENU_LOCAL_TASK,
    'weight' => 3,
  );
  // Default settings.
  $items['admin/config/people/userprotect/protection_defaults'] = array(
    'title' => 'Protection defaults',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('userprotect_protection_defaults'),
    'access callback' => 'user_access',
    'access arguments' => $admin,
    'type' => MENU_LOCAL_TASK,
    'weight' => 4,
  );
  // Remove a user from being protected.
  $items['userprotect/delete'] = array(
    'title' => 'Delete protected user',
    'page callback' => 'userprotect_protected_users_delete',
    'type' => MENU_CALLBACK,
    'access callback' => 'user_access',
    'access arguments' => $admin,
  );

  return $items;
}
/**
 * Implement hook_menu_alter().
 *
 *  Since we also have to guard against menu items being called
 *  directly from a URL, this page check is necessary.  The checks
 *  are invoked for user/x/edit and user/x/cancel, and replace user
 *  modules's default access checks.
 */
function userprotect_menu_alter(&$callbacks) {
  $callbacks['user/%user/edit']['access callback'] = 'userprotect_user_edit_access';
  $callbacks['user/%user/cancel']['access callback'] = 'userprotect_user_cancel_access';
}

/**
 * Access callback for user edit pages.
 *
 * This replaces user_edit_access from user.module.
 *
 * @param $account
 *   An object representing the user to be edited.
 */
function userprotect_user_edit_access($account) {
  // Perform core's access check.
  if ((($GLOBALS['user']->uid == $account->uid) || user_access('administer users')) && $account->uid > 0) {
    // Check to see if the user's roles are protecting edits, or the user
    // account itself is protected.
    if (!userprotect_check_bypass('up_edit') && userprotect_get_user_protection($account, 'up_edit')) {
      // If so, and we're at /user/X/edit, set a message.
      if (arg(0) == 'user' && is_numeric(arg(1)) && arg(2) == 'edit') {
        drupal_set_message(t('%user is currently being protected from any edits.', array('%user' => $account->name)), 'error');
      }
      return FALSE;
    }
    else {
      return TRUE;
    }
  }
  else {
    return FALSE;
  }
}

/**
 * Access callback for user cancel pages.
 *
 * This replaces the logic from user.module.
 *
 * @param $account
 *   An object representing the user to be cancelled.
 */
function userprotect_user_cancel_access($account) {
  // Perform core's access check.
  if (((($GLOBALS['user']->uid == $account->uid) && user_access('cancel account')) || user_access('administer users')) && $account->uid > 0) {
    // At this point, we only need the userprotect-specific validation if:
    //   1. The current user and the edited user are not the same.
    //   2. The current user is a user administrator.
    if (($GLOBALS['user']->uid != $account->uid) && user_access('administer users')) {
      // Check to see if the user's roles are protecting cancellation, or the user
      // account itself is protected.
      if (!userprotect_check_bypass('up_cancel') && userprotect_get_user_protection($account, 'up_cancel')) {
        // If so, and we're at /user/X/cancel, set a message.
        if (arg(0) == 'user' && is_numeric(arg(1)) && arg(2) == 'cancel') {
          drupal_set_message(t('%user is currently being protected from cancellation.', array('%user' => $account->name)), 'error');
        }
        return FALSE;
      }
    }
    else {
      return TRUE;
    }
  }
  else {
    return FALSE;
  }
}

/**
 * Implement hook_permission().
 */
function userprotect_permission() {
  return array(
    'change own e-mail' => array(
      'title' => t('Change own e-mail'),
      'description' => t('Allow users to edit their own e-mail address.'),
    ),
    'change own password' => array(
      'title' => t('Change own password'),
      'description' => t('Allow users to edit their own password.'),
    ),
    'change own openid' => array(
      'title' => t('Change own OpenID'),
      'description' => t('Allow users to edit their own OpenID identities.'),
    ),
    'administer userprotect' => array(
      'title' => t('Administer User Protect'),
      'description' => t('Set up access rules for user administrators for various user-related edits.'),
    ),
  );
}

/**
 * Implement hook_theme().
 */
function userprotect_theme() {
  return array(
    'userprotect_admin_role_table' => array(
      'render element' => 'form',
    ),
    'userprotect_protections_bypass' => array(
      'render element' => 'form',
    ),
  );
}

/**
 * Implement hook_user_insert().
 */
function userprotect_user_insert(&$edit, $account) {

  // A new user is being added.  If auto-protect is enabled, then add protection.
  if (variable_get('userprotect_autoprotect', FALSE)) {
    userprotect_add_user($account->uid, 'user');
    $protected = array_filter(variable_get('userprotect_protection_defaults', userprotect_user_protection_defaults()));
    drupal_set_message(userprotect_display_protections($account, $protected));
  }
}


/**
 * Implement hook_user_cancel().
 */
function userprotect_user_cancel($edit, $account, $method) {
  switch ($method) {
    // Remove a deleted user from the protections table.
    case 'user_cancel_reassign':
    case 'user_cancel_delete':
      db_delete('userprotect')
        ->condition('uid', $account->uid)
        ->execute();
      break;
  }
}

/**
 * Builds a table of protected users, and their protections.
 *
 * @return A form array representing the table.
 */
function userprotect_protected_users() {
  return userprotect_protections_bypass('user');
}

/**
 * Builds a table of user admin bypass values.
 *
 * @return A form array representing the table.
 */
function userprotect_administrator_bypass() {
  return userprotect_protections_bypass('admin');
}

/**
 * Helper funtion.  Builds tables for protected users and admin bypass.
 *
 * @return A form array representing the table.
 */
function userprotect_protections_bypass($type) {

  // Build the header.
  $header = array(array('data' => t('User'), 'field' => 'name', 'sort' => 'asc'));

  $protect_columns = userprotect_get_protection_display();
  foreach ($protect_columns as $field => $data) {
  	$header[] = array('data' => $data, 'field' => $field);
  }
  $header[] = array('data' => t('Operations'));

  $query = db_select('userprotect', 'up');
  $query->innerJoin('users', 'u', 'up.uid = u.uid');
  $query->condition('up.up_type', $type);

  $count_query = clone $query;
  $count_query->addExpression('COUNT(DISTINCT u.uid)');

  $query = $query->extend('PagerDefault')->extend('TableSort');

  // These are all protection fields in the database.
  $protection_fields = array_keys(userprotect_get_protection_display());

  // Grab the protected users.
  $query
    ->fields('up', $protection_fields)
    ->fields('u', array('uid', 'name'))
    ->limit(25)
    ->orderByHeader($header)
    ->setCountQuery($count_query);
  $protected_users = $query->execute();

  // Set some initial values.
  $delete = t('delete');
  $options = array();

  // These are all available protections.
  $protections = array_keys(userprotect_user_protection_defaults());

  // Pass in the header and list of protections to the form so they'll be available
  // to the theming function.
  $form = array();
  $form['protection']['#tree'] = TRUE;
  $form['#header'] = $header;
  $form['#protections'] = $protections;
  $form['#submit'][] = 'userprotect_protections_bypass_submit';
  $form['#theme'] = 'userprotect_protections_bypass';

  // Build the checkboxes options.
  foreach ($protections as $protection) {
  	$options[$protection] = '';
  }

  // For each protected user, build their table row.
  foreach ($protected_users as $protected_user) {
    $defaults = array();

    $user = user_load($protected_user->uid);

    $form['user'][$user->uid]['uid'] = array(
      '#type' => 'value',
      '#value' => $user->uid
    );
    $form[$user->uid]['name'] = array(
      '#theme' => 'username',
      '#account' => $user,
    );
    $form[$user->uid]['operations'] = array('#markup' => $user->uid ? l($delete, "userprotect/delete/$user->uid/$type") : '');
    // Build the protections for the user row.
    foreach ($protections as $protection) {
    	if ($protected_user->$protection) {
    	  $defaults[] = $protection;
    	}
    }

    // The checkboxes for this user.
    $form['protection'][$user->uid] = array(
      '#type' => 'checkboxes',
  	  '#options' => $options,
  	  '#default_value' => $defaults,
  	);
  }

  // An autocomplete field to add new users for protection.
  // This needs a custom validation function to check the user
  // to be added.
  $form['up_add'] = array(
    '#type' => 'textfield',
    '#maxlength' => 60,
    '#autocomplete_path' => 'user/autocomplete',
    '#element_validate' => array('userprotect_up_add_validate'),
    '#userprotect_type' => $type,
  );
  $form['up_add_text'] = array('#markup' => t('Add user'),);
  $form['userprotect_type'] = array(
    '#type' => 'value',
    '#value' => $type,
  );

  $form['pager'] = array(
    '#theme' => 'pager',
    '#tags' => NULL,
  );

  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Save')
  );
  return $form;
}

/**
 * Themes the protected users table.
 *
 * @param $form The form to theme.
 * @return An HTML string representing the constructed form.
 */
function theme_userprotect_protections_bypass($variables) {
  $form = $variables['form'];
  $rows = array();
  // Buikd the row for each user.
  foreach (element_children($form['user']) as $uid) {
  	$row = array();
  	$row[] = drupal_render($form[$uid]['name']);
  	// Build the protections for the user row.
  	foreach ($form['#protections'] as $protection) {
  		$row[] = drupal_render($form['protection'][$uid][$protection]);
  	}
  	$row[] = drupal_render($form[$uid]['operations']);
  	$rows[] = $row;
  }

  // Add the last row with the add textfield.
  $rows[] = array(
    array('data' => drupal_render($form['up_add']), 'colspan' => strval(count($form['#header']) - 1)),
    array('data' => drupal_render($form['up_add_text']), 'colspan' => '1')
  );

  // Theme the table.
  $output = theme('table', array('header' => $form['#header'], 'rows' => $rows));
  $output .= drupal_render_children($form);

  return $output;
}

/**
 * Custom validation function for adding a user for protection.
 */
function userprotect_up_add_validate($form, &$form_state) {
  // If a user has been submitted
  if ($username = $form['#value']) {
    $type = $form['#userprotect_type'];
    // If the user is valid, and they are not already being protected...
    if ($uid = db_query("SELECT uid FROM {users} WHERE name = :name", array(
      ':name' => $username,
    ))->fetchField()) {
      if (!db_query("SELECT uid FROM {userprotect} WHERE uid = :uid AND up_type = :up_type", array(
        ':uid' => $uid,
        ':up_type' => $type,
      ))->fetchField()) {
        if ($uid != 1 && $type == 'admin' && !db_query("SELECT ur.uid FROM {users_roles} ur INNER JOIN {role_permission} rp ON ur.rid = rp.rid WHERE rp.permission = :permission AND ur.uid = :uid", array(
          ':permission' => 'administer users',
          ':uid' => $uid,
        ))->fetchField()) {
          form_set_error('up_add', t('%user does not have user administration privileges.', array('%user' => $username)));
        }
        else {
          // Transform the username into a uid.
          form_set_value($form, $uid, $form_state);
        }
      }
      // Can't add a user twice
      else {
        form_set_error('up_add', t('%user is already on this list.', array('%user' => $username)));
      }

    }
    // Can't add a user that doesn't exist.
    else {
      form_set_error('up_add', t('The username is invalid.'));
    }
  }
}

/**
 * Processes the submitted user protection form.
 */
function userprotect_protections_bypass_submit($form, &$form_state) {

  $type = $form_state['values']['userprotect_type'];

  // A user was added, so add them to the protected users table.
  if ($uid = $form_state['values']['up_add']) {
    userprotect_add_user($uid, $type);
    $username = userprotect_get_username($uid);
    if ($type == 'user') {
      drupal_set_message(t('%user is now protected.', array('%user' => $username)));
    }
    elseif ($type == 'admin') {
      drupal_set_message(t('%user now has bypass capabilities matching the default protections for newly protected users.', array('%user' => $username)));
    }
  }
  if (is_array($form_state['values']['protection'])) {
    // Load the defaults as a reference to all protections.
    $protections_values = userprotect_user_protection_defaults();
    // Loop through each user.
    foreach ($form_state['values']['protection'] as $uid => $protections) {
      $fields = array();
      // Loop through the submitted user's protections, setting them enabled or
      // disabled as appropriate for the update query. Note: $protection is
      // a module generated string, so it's safe.
    	foreach ($protections_values as $protection => $value) {
        $fields[$protection] = $protections[$protection] ? 1 : 0;
    	}

    	// Update the user's protections.
      db_update('userprotect')
        ->fields($fields)
        ->condition('uid', $uid)
        ->condition('up_type', $type)
        ->execute();
    }
    if ($type == 'user') {
      drupal_set_message(t('Protection settings updated.'));
    }
    elseif ($type == 'admin') {
      drupal_set_message(t('Bypass settings updated.'));
    }
  }
}

/**
 * Menu callback.  Removes a user from being protected.
 *
 * @param $uid The user ID to remove.
 */
function userprotect_protected_users_delete($uid, $type) {
  if ($uid) {
    db_delete('userprotect')
      ->condition('uid', $uid)
      ->condition('up_type', $type)
      ->execute();
    $username = userprotect_get_username($uid);
    if ($type == 'user') {
      drupal_set_message(t('%user is no longer protected.', array('%user' => $username)));
      drupal_goto('admin/config/people/userprotect/protected_users');
    }
    elseif ($type == 'admin') {
      drupal_set_message(t('%user is no longer enabled for bypass.', array('%user' => $username)));
      drupal_goto('admin/config/people/userprotect/administrator_bypass');
    }
  }
  else {
    drupal_set_message(t('Invalid selection.'), 'error');
    drupal_goto('admin/config/people/userprotect');
  }
}

/**
 * Builds a form for the role protection settings.
 *
 * @return An array representing the form.
 */
function userprotect_protected_roles() {

  $form = array();

  // Get the list of all protections, and the current default settings.
  $options = userprotect_get_protection_display();

  // Build the header.
  $header = array(t('Role'));
  foreach ($options as $field => $data) {
  	$header[] = $data;
  }

  // Grab all roles but the anonymous role, and grab the current default settings.
  $roles = user_roles(TRUE);
  $protected_roles = variable_get('userprotect_role_protections', array());

  // This is a complete list of protections for reference.
  $protections = array_keys(userprotect_user_protection_defaults());

  // Pass in the header and protections so they're available for the theme function.
  // Also, we want this as one big array to save in the variables table, so tree it.
  $form['role_table']['#header'] = $header;
  $form['role_table']['#theme'] = 'userprotect_admin_role_table';
  $form['role_table']['#protections'] = $protections;
  $form['role_table']['userprotect_role_protections']['#tree'] = TRUE;

  // Build a row for each role.
  foreach ($roles as $rid => $role) {
    $form['role_table']['userprotect_role_protections'][$rid]['name'] = array('#markup' => $role);
    // Build protections for the row.
    foreach ($protections as $protection) {
      $form['role_table']['userprotect_role_protections'][$rid][$protection] = array(
        '#type' => 'checkbox',
      );
      if (isset($protected_roles[$rid][$protection])) {
        $form['role_table']['userprotect_role_protections'][$rid][$protection]['#default_value'] = $protected_roles[$rid][$protection];
      }
    }
  }

  return system_settings_form($form);
}

/**
 * Builds a form for the userprotect default settings.
 *
 * @return An array representing the form.
 */
function userprotect_protection_defaults() {

  // Get the list of all protections, and the current default settings.
  $options = userprotect_get_protection_display();
  $current_defaults = variable_get('userprotect_protection_defaults', userprotect_user_protection_defaults());

  // Transform the defaults into proper checkboxes defaults.
  $defaults = array_keys(array_filter($current_defaults));

  // A set of checkboxes that lists the default protection settings.
  $form['userprotect_protection_defaults'] = array(
    '#type' => 'checkboxes',
    '#title' => t('User protection defaults'),
    '#description' => t('The selected protections will be assigned to users when they are first added for protection.'),
    '#options' => $options,
    '#default_value' => $defaults,
  );
  // A checkbox to enable the auto-protect functionality.
  $form['userprotect_autoprotect'] = array(
    '#type' => 'checkbox',
    '#title' => t('Auto-protect new users'),
    '#description' => t('If selected, all newly created users will automatically be protected and assigned the default protections above.'),
    '#default_value' => variable_get('userprotect_autoprotect', FALSE),
  );
  // A set of checkboxes that lists the default protection settings.
  $form['userprotect_administrator_bypass_defaults'] = array(
    '#type' => 'checkboxes',
    '#title' => t('Administrator bypass defaults'),
    '#description' => t('If selected, all users with the \'administer users\' permission will be allowed to bypass the protection<br \><em>Note: this default setting is overridden by the <a href="!per_user_bypass">per-user administrator bypass settings</a>.</em>.', array('!per_user_bypass' => url('admin/config/people/userprotect/administrator_bypass'))),
    '#options' => $options,
    '#default_value' => variable_get('userprotect_administrator_bypass_defaults', userprotect_administrator_bypass_defaults()),
  );

  return system_settings_form($form);
}

/**
 * Themes the role protections table.
 *
 * @param $form The form for the table.
 * @return An HTML string representing the table.
 */
function theme_userprotect_admin_role_table($variables) {
  $form = $variables['form'];
  $rows = array();
  // Build a row for each role
  foreach (element_children($form['userprotect_role_protections']) as $rid) {
  	$row = array();
  	$row[] = drupal_render($form['userprotect_role_protections'][$rid]['name']);
  	// Build the protections for each row.
  	foreach ($form['#protections'] as $protection) {
  		$row[] = drupal_render($form['userprotect_role_protections'][$rid][$protection]);
  	}
  	$rows[] = $row;
  }

  // Theme the table.
  $output = t('<h3>Protections by role</h3>');
  $output .= theme('table', array('header' => $form['#header'], 'rows' => $rows));
  $output .= t('<div class="description">Setting a protection for a role will enable that protection for all users in the role.</div>');
  $output .= drupal_render_children($form);

  return $output;
}

/**
 * Custom validation function for protecting users from the user
 * administration operations.
 */
function userprotect_user_admin_account_validate($form, &$form_state) {

  // Get the checked users, and the operation name.
  $uids = array_filter($form_state['values']['accounts']);
  $operation_rid = explode('-', $form_state['values']['operation']);
  $operation = $operation_rid[0];

  // Perform the check for each submitted user.
  foreach ($uids as $uid) {
    $account = user_load($uid);

	  switch ($operation) {
      case 'block':
      case 'unblock':
        // Check to see if any of the user's roles are protected from status changes,
        // then check to see if the user is protected.
        if (!userprotect_check_bypass('up_status') && userprotect_get_user_protection($account, 'up_status')) {
          // If so, then unset the checked user so they will not be processed, and display a warning.
          form_set_value($form['accounts'][$uid], 0, $form_state);
          drupal_set_message(t('%user is protected from status changes, and was not updated.', array('%user' => $account->name)), 'error');
          unset($uids[$uid]);
        }
        break;
      case 'cancel':
        // Check to see if any of the user's roles are protected from cancellation,
        // then check to see if the user is protected.
        if (!userprotect_check_bypass('up_cancel') && userprotect_get_user_protection($account, 'up_cancel')) {
          // If so, then unset the checked user so they will not be processed, and display a warning.
          // Note that the array element has to be completely removed here in order to prevent the
          // user from being cancelled, due to the nature of the mass cancellation callback.
          unset($form_state['values']['accounts'][$uid]);
          drupal_set_message(t('%user is protected from cancellation, and was not cancelled.', array('%user' => $account->name)), 'error');
          unset($uids[$uid]);
        }
        break;
      case 'add_role':
      case 'remove_role':
      // RoleAssign module compatibility hack.
      case 'roleassign_add_role':
      case 'roleassign_remove_role':
        // Check to see if any of the user's roles are protected from status changes,
        // then check to see if the user is protected.
        if (!userprotect_check_bypass('up_roles') && userprotect_get_user_protection($account, 'up_roles')) {
          // If so, then unset the checked user so they will not be processed, and display a warning.
          form_set_value($form['accounts'][$uid], 0, $form_state);
          drupal_set_message(t('%user is protected from role changes, and was not updated.', array('%user' => $account->name)), 'error');
          unset($uids[$uid]);
        }
        break;
    }
  }

  // If we've unset all of the users that were checked, then don't continue
  // with the form processing.
  if (!count($uids)) {
    drupal_set_message('No users selected.', 'error');
    drupal_goto('admin/people');
  }
}

/**
 * Builds an array of the inital default protections.
 *
 * @return The default protections array.
 */
function userprotect_user_protection_defaults() {
  return array('up_name' => 0,
    'up_mail' => 0,
    'up_pass' => 0,
    'up_status' => 1,
    'up_roles' => 0,
    'up_openid' => 0,
    'up_cancel' => 1,
    'up_edit' => 0,
  );
}

/**
 * Builds an array of the inital default bypass settings for user admins.
 *
 * @return The default bypass array.
 */
function userprotect_administrator_bypass_defaults() {

  $defaults = array();
  $protections = userprotect_user_protection_defaults();
  foreach ($protections as $protection => $value) {
  	$defaults[$protection] = $protection;
  }

  return $defaults;
}

/**
 * Builds an array of all protections and their human-readable text string.
 *
 * @return The constructed array.
 */
function userprotect_get_protection_display() {
  return array('up_name' => t('username'),
    'up_mail' => t('e-mail'),
    'up_pass' => t('password'),
    'up_status' => t('status'),
    'up_roles' => t('roles'),
    'up_openid' => t('openid'),
    'up_cancel' => t('cancel'),
    'up_edit' => t('all account edits'),
  );
}

/**
 * Conditionally displays a user message on edit forms listing current
 * protections.
 *
 * @param $account The user account object.
 * @param $protected An array of protections the current user is receiving.
 */
function userprotect_form_display_protections($account, $protected) {
  // If we're initially displaying an edit form, throw a message if
  // there are any protected fields, so the editor has a clue.
  if (!empty($protected) && !$_POST) {
    drupal_set_message(userprotect_display_protections($account, $protected));
  }
}

/**
 * Builds a displayable text string of the protections currently in effect for
 * the specified user.
 *
 * @param $account The user account object.
 * @param $protected An array of protections the current user is receiving.
 *
 * @return A text string representing the current protections.
 */
function userprotect_display_protections($account, $protected) {

  // Get the protections display text.
  $display = userprotect_get_protection_display();

  $protections = array();
  // For each protection, check if any of the user's roles are protected, or the user is
  // protected.
  foreach ($protected as $protection => $value) {
  	$protections[] = $display[$protection];
  }
  // Display if there are protections and it's an admin user.
  if (count($protections) && user_access('administer users')) {
    $output = t('%user has been protected from the following editing operations: !operations', array('%user' => $account->name, '!operations' => implode(', ', $protections)));
  }
  else {
    $output = '';
  }

  return $output;
}

/**
 * Adds a user to the protections table.
 *
 * @param $uid The UID of the user to be added.
 * @param $type The type of protection to add, either 'user', or 'admin'.
 */
function userprotect_add_user($uid, $type) {
  // Grab the default protections to enable for this user.
  $protections = variable_get('userprotect_protection_defaults', userprotect_user_protection_defaults());

  // Set initial fields.
  $fields = array(
    'uid' => $uid,
    'up_type' => $type,
  );

  // Add the protections.
  foreach ($protections as $protection => $value) {
    $fields[$protection] = $protections[$protection] ? 1 : 0;
  }

  db_insert('userprotect')
    ->fields($fields)
    ->execute();
}

/**
 * Gives the username of a protected user.
 *
 * @param $uid The user ID.
 * @return The username.
 */
function userprotect_get_username($uid) {
  return db_query('SELECT name FROM {users} WHERE uid = :uid', array(
    ':uid' => $uid,
  ))->fetchField();
}

/**
 * Checks to see if the current user can bypass a protection.
 *
 * @param $protection The protection to check for bypass.
 * @param $uid An optional user to perform the bypass check on (default is current user).
 *
 * @return TRUE if the user can bypass, FALSE otherwise.
 */
function userprotect_check_bypass($protection, $uid = NULL) {

  $bypass = &drupal_static(__FUNCTION__, array());
  $bypass_defaults = &drupal_static(__FUNCTION__ . '_defaults', NULL);

  // If not a user admin, no checks necessary.
  if (!user_access('administer users')) {
    return FALSE;
  }

  // Take the current user unless otherwise specified.
  $uid = isset($uid) ? $uid : $GLOBALS['user']->uid;

  // Set the static array for the current admin.
  if (!isset($bypass[$uid])) {
    $result = db_query("SELECT * FROM {userprotect} WHERE uid = :uid AND up_type = :up_type", array(
      ':uid' => $uid,
      ':up_type' => 'admin',
    ));
    if ($admin_array = $result->fetchAssoc()) {
      $bypass[$uid] = $admin_array;
    }
  }

  // If a per administrator bypass setting exists, return it.
  if (isset($bypass[$uid][$protection])) {
    return $bypass[$uid][$protection];
  }
  // Otherwise return the default bypass setting.
  else {
    if (!isset($bypass_defaults)) {
      $bypass_defaults = variable_get('userprotect_administrator_bypass_defaults', userprotect_administrator_bypass_defaults());
    }

    return isset($bypass_defaults[$protection]) ? $bypass_defaults[$protection] : FALSE;
  }

}

/**
 * Checks to see if the specified user has the specified protection.
 *
 * @param $account The user object to check.
 * @param $protection The protection to check for.
 * @return TRUE if the user has the specified protection, FALSE otherwise.
 */
function userprotect_get_user_protection($account, $protection) {

  $protections = &drupal_static(__FUNCTION__, array());
  $role_protections = &drupal_static(__FUNCTION__ . '_roles', NULL);

  $uid = $account->uid;
  $roles = $account->roles;

  // Users editing their own accounts have the permissions for e-mail
  // and password determined by the role-based setting in the userprotect
  // section at admin/config/people/permissions. This is done for consistency
  //  with the way core handles the self-editing of usernames.
  if ($uid == $GLOBALS['user']->uid && in_array($protection, array('up_name', 'up_mail', 'up_pass', 'up_openid', 'up_edit'))) {
    switch ($protection) {
      case 'up_name':
        return !user_access('change own username');
      case 'up_mail':
        return !user_access('change own e-mail');
      case 'up_pass':
        return !user_access('change own password');
      case 'up_openid':
        return !user_access('change own openid');
      // Always let user access their own edit page.
      case 'up_edit':
        return FALSE;
    }
  }

  // If this user hasn't been added to the result array yet, then pull their information.
  if (!isset($protections[$uid])) {

    $result = db_query("SELECT * FROM {userprotect} WHERE uid = :uid AND up_type = :up_type", array(
      ':uid' => $uid,
      ':up_type' => 'user',
    ));
    if ($user_array = $result->fetchAssoc()) {
      $protections[$uid] = $user_array;
    }
  }

  // If per-user protections exist for this user, stop here and return the value of the protection.
  if (isset($protections[$uid][$protection])) {
    return $protections[$uid][$protection];
  }

  // Grab the role protections if they haven't already been initialized.
  if (!isset($role_protections)) {
    $role_protections = variable_get('userprotect_role_protections', array());
  }

  if (!empty($role_protections)) {
    // For each role, check to see if it's enabled for that protection.
    // Return TRUE as soon as we find a protected role.
    foreach ($roles as $rid => $role) {
      if ($role_protections[$rid][$protection]) {
        return TRUE;
      }
    }
  }

  // No protection enabled.
  return FALSE;
}