' . t('Adds a Captcha to various forms to help prevent spam submissions.') .'
'; + case 'admin/settings/captcha': + return '' . t('Captchas are meant to counter spam submissions. Captchas are extra fields on a form presented to the anonymous visitors. These fields present a challenge, which should be easy for a human to solve, but hard enough to keep automated scripts and bots out.') . '
'; } return $output; } @@ -26,136 +27,173 @@ function captcha_menu($may_cache) { 'path' => 'admin/settings/captcha', 'title' => t('Captcha'), 'description' => t('Administer how and where Captchas are used.'), - 'callback' => 'drupal_get_form', - 'callback arguments' => array('captcha_admin_settings'), + 'callback' => 'captcha_admin', 'access' => user_access('administer site configuration'), 'type' => MENU_NORMAL_ITEM, ); - $items[] = array( - 'path' => 'admin/settings/captcha/captcha', - 'title' => t('Captcha'), - 'description' => t('Administer how and where Captchas are used.'), - 'access' => user_access('administer site configuration'), - 'type' => MENU_DEFAULT_LOCAL_TASK, - ); - $items[] = array( - 'path' => 'admin/settings/captcha/points', - 'title' => t('Captcha Points'), - 'description' => t('Administer in what forms Captchas are applied.'), - 'callback' => 'drupal_get_form', - 'callback arguments' => array('captcha_admin_points'), - 'access' => user_access('administer site configuration'), - 'type' => MENU_LOCAL_TASK, - ); } return $items; } - +/** + * Return an array with the available captcha types + */ function _captcha_supported_challenges_types(){ static $captcha_challenges = NULL; - + // if cached: return cache if($captcha_challenges != NULL) { return $captcha_challenges; } - $captcha_challenges['none'] = 'none'; - foreach(module_implements('captcha') as $module) { $result = call_user_func_array($module .'_captcha', 'list'); if (isset($result)) { //&& is_array($result)) { foreach($result as $challenge) { - $captcha_challenges[$module.'/'.$challenge] = $module.'/'.$challenge; + $captcha_challenges["$module::$challenge"] = "$module::$challenge"; } } } - - return $captcha_challenges; } -function _captcha_points() { - $captcha_points = variable_get('captcha_points',NULL); - if($captcha_points == NULL) { - $captcha_points = array( - 'comment_form' => t('Comment form'), - 'contact_mail_user' => t('User contact form'), - 'contact_mail_page' => t('Sitewide contact form'), - ); - variable_set('captcha_points',serialize($captcha_points)); +/** + * General Captcha settings handler + * + * If arguments are given: first argument is used as form_id, the second one + * is interpreted as action (such as disable, delete and enable) to execute on + * the form_id. + * Otherwise: returns the general captcha configuration form. + */ +function captcha_admin($form_id='', $op='') { + // if $form_id and action $op given: do the action + if ($form_id) { + switch ($op) { + case 'disable': + // disable the captcha point: set the captcha_type to NULL + db_query("UPDATE {captcha_points} SET captcha_type = NULL WHERE form_id = '%s'", $form_id); + drupal_set_message(t('Disabled captcha point %form_id.', array('%form_id'=>$form_id))); + // TODO: return to referer page? + drupal_goto('admin/settings/captcha'); + break; + case 'delete': + db_query("DELETE FROM {captcha_points} WHERE form_id = '%s'", $form_id); + drupal_set_message(t('Deleted captcha point %form_id.', array('%form_id'=>$form_id))); + drupal_goto('admin/settings/captcha'); + break; + case 'enable': + db_query("DELETE FROM {captcha_points} WHERE form_id = '%s'", $form_id); + db_query("INSERT INTO {captcha_points} (form_id, captcha_type) VALUES ('%s', NULL)", $form_id); + drupal_goto("admin/settings/captcha/$form_id"); + break; } - else { - $captcha_points = unserialize($captcha_points); } - return $captcha_points; + // no $form_id or legal action given: generate general captcha settings form + return drupal_get_form('captcha_admin_settings', $form_id); } -function captcha_admin_points() { - $captcha_points = _captcha_points(); - $output = ''; - - if(function_exists('form_store_get_all')) { - $form = array('#description' => t('Enable/Disable captcha points.')); - $known_forms = form_store_get_all(); - $form['captcha_points']['#tree'] = true; - foreach($known_forms as $item) { - $form['captcha_points'][$item->form_id] = array( +/** + * Form builder function for the general captcha configuration + */ +function captcha_admin_settings($form_id='') { + $form['#action'] = url('admin/settings/captcha'); + // field for the captcha adminstration mode + $form['captcha_administration_mode'] = array( '#type' => 'checkbox', - '#title' => $item->form_id.' - '.$item->description, - '#default_value' => isset($captcha_points[$item->form_id]), + '#title' => t('Add captcha adminstration links to forms.'), + '#default_value' => variable_get('captcha_administration_mode', FALSE), + '#description' => t('This option is very helpfull to enable/disable captchas on forms. When enabled, users with the "administer site configuration" permission will see captcha adminstration links on all forms.'), + ); + // field set with form_id -> captcha_type configuration + $form["captcha_types"] = array( + '#type' => 'fieldset', + '#title' => t('Select captcha types'), + '#description' => t('Select what kind of captcha challenge you want for each form.'), + '#tree' => TRUE, + '#collapsible' => TRUE, + '#collapsed' => FALSE, + '#theme' => 'captcha_admin_settings_captcha_points', + ); + // list all possible form_id's + $captcha_challenges = _captcha_supported_challenges_types(); + $result = db_query("SELECT * FROM {captcha_points} ORDER BY form_id"); + while ($captcha_point = db_fetch_object($result)) { + $form['captcha_types'][$captcha_point->form_id]['form_id'] = array( + '#value' => $captcha_point->form_id, + ); + // select widget for captcha_type + $form['captcha_types'][$captcha_point->form_id]['captcha_type'] = array( + '#type' => 'select', + '#default_value' => $captcha_point->captcha_type, + '#options' => $captcha_challenges, + ); + // if a form_id was given as argument of this form builder, highlight the captcha_type select widget + if ($form_id == $captcha_point->form_id) { + $form['captcha_types'][$captcha_point->form_id]['captcha_type']['#attributes'] = array('class'=>'error'); + } + // additional operations + $form['captcha_types'][$captcha_point->form_id]['operations'] = array( + '#value' => implode(", ", array( + l(t('delete'), "admin/settings/captcha/{$captcha_point->form_id}/delete"), + )) ); } - $output = system_settings_form($form); - } - else { - drupal_set_message(t('Unable to find Form Store module, Captcha needs it to allow you to change the capcha points.'),'error'); - } - - return $output; + // field for setting the additional captcha description + $form["captcha_description"] = array( + '#type' => 'textfield', + '#title' => t('Captcha description'), + '#description' => t('This description should explain to the anonymous visitor why the captcha needs to be solved.'), + '#default_value' => t(variable_get('captcha_description', CAPTCHA_DESCRIPTION)), + ); + // field for captcha persistency + $form["captcha_persist"] = array( + '#type' => 'checkbox', + '#title' => t('Persistent captchas'), + '#description' => t('If checked, a captcha will be presented to the user each time (s)he wants to submit concerning form. If not checked, once the user has successfully solved a captcha for a form, (s)he will not be presented a captcha for subsequent instances of that form.'), + '#default_value' => variable_get('captcha_persist', FALSE), + ); + // submit button + $form['submit'] = array( + '#type' => 'submit', + '#value' => t('Submit'), + ); + return $form; } -function captcha_admin_points_submit($form_id, $form_values) { - if($form_id == 'captcha_admin_points') { - $known_forms = form_store_get_all(); - $captcha_points = array(); - foreach($form_values['captcha_points'] as $key => $selected) { - if($selected) - $captcha_points[$key] = $known_forms[$key]->description; - } - variable_set('captcha_points',serialize($captcha_points)); - drupal_set_message(t('Your captcha points were sucessful updated, please configure the challenge options in the other tab.'),'status'); +/** + * Custom theme function for a table of (form_id -> captcha_type) settings + */ +function theme_captcha_admin_settings_captcha_points($form) { + foreach (element_children($form) as $key) { + $row = array(); + $row[] = drupal_render($form[$key]['form_id']); + $row[] = drupal_render($form[$key]['captcha_type']); + $row[] = drupal_render($form[$key]['operations']); + $rows[] = $row; } + $header = array('form_id', t('Captcha type'), t('Operations')); + $output = theme('table', $header, $rows); + return $output; } /** - * Helper function generates admin settings page. + * Submission function for captcha_admin_settings form */ -function captcha_admin_settings() { - $captcha_points = _captcha_points(); - $roles = variable_get('captcha_roles',user_roles()); - $captcha_challenges = _captcha_supported_challenges_types(); - - foreach($roles as $role) { - $varsuffix = strtr($role, ' ', '_') .'_captcha'; - $form[$varsuffix] = array( - '#type' => 'fieldset', - '#title' => t('Captcha points for the role @role', array('@role' => $role)), - '#description' => t('Select what kind of challenge you want to pose to the user in each captcha point.'), - '#collapsible' => TRUE, - '#collapsed' => TRUE, - ); - foreach($captcha_points as $captcha_point => $captcha_point_description) { - $varname = $captcha_point .'_'. $varsuffix; - $form[$varsuffix][$varname] = array( - '#type' => 'select', - '#title' => t('@point', array('@point' => $captcha_point_description)), - '#default_value' => variable_get($varname, 'captcha/Math'), - '#options' => $captcha_challenges, - ); +function captcha_admin_settings_submit($form_id, $form_values) { + if ($form_id == 'captcha_admin_settings') { + variable_set('captcha_administration_mode', $form_values['captcha_administration_mode']); + foreach($form_values['captcha_types'] as $form_id => $data) { + $captcha_type = $data['captcha_type']; + if ($captcha_type == 'none') { + db_query("UPDATE {captcha_points} SET captcha_type = NULL WHERE form_id = '%s'", $form_id); + } + else { + db_query("UPDATE {captcha_points} SET captcha_type = '%s' WHERE form_id = '%s'", $captcha_type, $form_id); } } - - return system_settings_form($form); + variable_set('captcha_description', $form_values['captcha_description']); + variable_set('captcha_persist', $form_values['captcha_persist']); + drupal_set_message(t('Your captcha settings were saved.'), 'status'); + } } /** @@ -165,89 +203,115 @@ function captcha_form_alter($form_id, &$ global $captcha; global $user; - $seed = $form['form_token']['#default_value']; - if($_SESSION['captcha'][$seed]['success'] === TRUE) - return; - - foreach($user->roles as $role) { - $candidate_trigger = $form_id .'_'. strtr($role, ' ', '_') .'_captcha'; - $captcha_type = variable_get($candidate_trigger,NULL); - - if($captcha_type != NULL) { - //Found one valid captcha challenge for this point. - break; + if (user_access('administer site configuration') && variable_get('captcha_administration_mode', FALSE)) { + // For administrators: show captcha info and offer link to configure it + $captcha_type = db_result(db_query("SELECT captcha_type FROM {captcha_points} WHERE form_id = '%s'", $form_id)); + if ($captcha_type) { + $form['captcha'] = array( + '#type' => 'item', + '#title' => t('Captcha administration'), + '#description' => t('The captcha challenge %captcha_type is enabled here for anonymous visitors: !disable.', array( + '%captcha_type' => $captcha_type, + '!disable' => l(t('disable captcha'), "admin/settings/captcha/$form_id/disable", array(), drupal_get_destination()))), + ); } + else { + $form['captcha'] = array( + '#type' => 'item', + '#title' => t('Captcha administration'), + '#description' => l(t('Place a captcha challenge here for anonymous visitors.'), "admin/settings/captcha/$form_id/enable"), + ); } - - if($captcha_type == 'none') { - //One of the user roles doesn't have captcha challenge for this point, aborting. + } + elseif ($user->uid) { + // captcha is only for anonymous users, so return return; } - elseif($captcha_type == NULL) { - //captcha_type null; + else { + $seed = $form['form_token']['#default_value']; + // do not present captcha if not captcha-persistent and user has already solved a captcha for this form + if(!variable_get('captcha_persist', FALSE) && ($_SESSION['captcha'][$seed]['success'] === TRUE)) { return; } - - $challenge = explode('/',$captcha_type); - - $result = module_invoke($challenge[0], 'captcha', 'generate', $challenge[1]); + // get captcha type and return if no captcha set + $captcha_type = db_result(db_query("SELECT captcha_type FROM {captcha_points} form_id = '%s'", $form_id)); + if (!$captcha_type) { + return; + } + // get captcha module + list($captcha_module, $captcha_type) = explode('::', $captcha_type); + $result = module_invoke($captcha_module, 'captcha', 'generate', $captcha_type); if (!$result) { - //The user selected module returned nothing, maybe it is disabled or it's wrong, we should watchdog that and the quit. - watchdog('captcha', - t('Problems when trying to retrieve captcha %challenge challenge from %module', - array('%challenge' => $challenge[1], '%module' => $challenge[0])), - WATCHDOG_ERROR); return; } - - $form = array_merge($form,$result['form']); - - if(!isset($form['#validate'])) + $captcha_description = variable_get('captcha_description', CAPTCHA_DESCRIPTION); + if ($captcha_description) { + $form['captcha'] = array( + '#type' => 'fieldset', + '#title' => t('Captcha'), + '#description' => t($captcha_description), + ); + } + else { + $form['captcha'] = array(); + } + $form['captcha'] = array_merge($form['captcha'], $result['form']); + // handle validate and prerender attributes + if(!isset($form['#validate'])) { $form['#validate'] = array(); + } $form['#validate'] += array('captcha_validate' => array()); $form['#pre_render'] = array('captcha_prerender'); - + // save captcha data in session $_SESSION['captcha'][$seed]['success'] = FALSE; $_SESSION['captcha'][$seed]['form_id'] = $form_id; $_SESSION['captcha'][$seed]['form'] = $result['form']; - $_SESSION['captcha'][$seed]['new_value'] = $result['value']; + $_SESSION['captcha'][$seed]['new_captcha_solution'] = $result['value']; $_SESSION['captcha'][$seed]['preprocess'] = isset($result['preprocess'])? $result['preprocess'] : FALSE; - $_SESSION['captcha'][$seed]['module'] = $challenge[0]; - $_SESSION['captcha'][$seed]['type'] = $challenge[1]; + $_SESSION['captcha'][$seed]['module'] = $captcha_module; + $_SESSION['captcha'][$seed]['type'] = $captcha_type; + } + //handle position of captcha: just above (last) submit button + foreach(element_children($form) as $key) { + if ($form[$key]['#type'] == 'submit') { + $submit_key = $key; + } + } + if (!$form[$submit_key]['#weight']) { + $form[$submit_key]['#weight'] = 30; + } + $form['captcha']['#weight'] = $form[$submit_key]['#weight'] - 1; } -function captcha_validate($form_id, $form_item) { - $seed = $form_item['form_token']; - +/** + * Implementation of form #validate. + */ +function captcha_validate($form_id, $form_values) { + $seed = $form_values['form_token']; + // get answer and preprocess if needed + $captcha_answer = $form_values['captcha_challenge']; if($_SESSION['captcha'][$seed]['preprocess']) { - $value = module_invoke($_SESSION['captcha'][$seed]['module'],'captcha','process',$_SESSION['captcha'][$seed]['type'],$form_item['captcha_challenge']); - } - else { - $value = $form_item['captcha_challenge']; + $captcha_answer = module_invoke($_SESSION['captcha'][$seed]['module'], 'captcha', 'process', $_SESSION['captcha'][$seed]['type'], $captcha_answer); } - - if($value == $_SESSION['captcha'][$seed]['value']) { + // check answer + if($captcha_answer == $_SESSION['captcha'][$seed]['captcha_solution']) { $_SESSION['captcha'][$seed]['success'] = TRUE; return; } - form_set_error('captcha_response', t('The answer you entered to the captcha challenge is incorrect.')); + else { + form_set_error('captcha_challenge', t('The answer you entered to the captcha challenge is incorrect.')); + } } /** * Implementation of form #pre_render. - * */ function captcha_prerender($form_id, $form) { - $seed = $form['#post']['form_token']; - $_SESSION['captcha'][$seed]['value'] = $_SESSION['captcha'][$seed]['new_value']; - if($_SESSION['captcha'][$seed]['success']) { - unset($form['captcha_challenge']); - unset($_SESSION['captcha'][$seed]); - } + $seed = $form['form_token']['#default_value']; + // store the captcha solution in the session array + $_SESSION['captcha'][$seed]['captcha_solution'] = $_SESSION['captcha'][$seed]['new_captcha_solution']; } - - /** * Default implementation of hook_captcha */ @@ -264,12 +328,11 @@ function captcha_captcha() { $answer = mt_rand(1, 20); $x = mt_rand(1, $answer); $y = $answer - $x; - - $result['value'] = (string)($answer); + $result['value'] = "$answer"; $result['form']['captcha_challenge'] = array ( '#type' => 'textfield', - '#title' => t('Math Question: What is %problem?', array('%problem' => $x .' + '. $y)), - '#description' => t('Please solve the math problem above and type in the result. e.g. for 1+1, type 2.'), + '#title' => t('Math Question: What is %problem?', array('%problem' => "$x + $y")), + '#description' => t('Solve this simple math problem and enter the result. E.g. for 1+3, type 4.'), '#weight' => 0, '#required' => TRUE, );