Issue #2907951 by aaron.ferris, tombsage: Captcha field validating error

clientside_validation.js

@@ -1061,7 +1061,7 @@
         'type': "POST",
         'data': {
           'value': value,
-          'param': [sid, param.validate, param.token]
+          'param': [sid, param.captcha_validate, param.token, param.captcha_token]
         },
         'dataType': 'json',
         'async': false,

clientside_validation.module

@@ -226,7 +226,9 @@ function _clientside_validation_ajax_captcha() {
     $csid = $_POST['param'][0];
     $captcha_validate = $_POST['param'][1];
     $token = $_POST['param'][2];
-    if (!drupal_valid_token($token, $captcha_validate)) {
+    $captcha_token = $_POST['param'][3];
+
+    if (!clientside_validation_valid_token($token, $captcha_validate, $captcha_token)) {
       return drupal_access_denied();
     }
     $solution = db_query(
@@ -1329,12 +1331,18 @@ function _clientside_validation_set_date($name, $title, $format, &$js_rules, $me
   $js_rules[$name]['messages']['dateFormat'] = theme('clientside_error', $variables);
 }
 
-function _clientside_validation_set_captcha($name, $title, $validate, &$js_rules, $message) {
+function _clientside_validation_set_captcha($name, $title, $validate, &$js_rules, $message, $captcha_token) {
   $title = _clientside_validation_set_title($title);
+
+  // Generate a token to validate the AJAX post values.
+  $token = clientside_validation_generate_token($validate, $captcha_token);
+
   $js_rules[$name]['captcha'] = array(
-    'validate' => $validate,
-    'token' => drupal_get_token($validate),
+    'captcha_validate' => $validate,
+    'token' => $token,
+    'captcha_token' => $captcha_token,
   );
+
   $variables = array(
     'message' => empty($message) ? 'Wrong answer for !title.' : $message,
     'placeholders' => empty($message) ? array('!title' => $title) : array(),
@@ -1661,3 +1669,38 @@ function _clientside_validation_url_validation_callback() {
 
   drupal_json_output($result);
 }
+
+/**
+ * Generate a token to validate AJAX post parameters.
+ *
+ * @param string $captcha_validate
+ *   The Captcha validation method.
+ *
+ * @param string $captcha_token
+ *   A token generated from Captcha.
+ *
+ * @return string
+ *   The generated validation token.
+ */
+function clientside_validation_generate_token($captcha_validate, $captcha_token) {
+  return drupal_hmac_base64($captcha_validate, $captcha_token . drupal_get_private_key() . drupal_get_hash_salt());
+}
+
+/**
+ * Validate a token during AJAX post.
+ *
+ * @param string $token
+ *   The generated validation token.
+ *
+ * @param string $captcha_validate
+ *   The Captcha validation method.
+ *
+ * @param string $captcha_token
+ *   A token generated from Captcha.
+ *
+ * @return boolean
+ *   TRUE if the token validates successfully.
+ */
+function clientside_validation_valid_token($token, $captcha_validate, $captcha_token) {
+  return ($token === clientside_validation_generate_token($captcha_validate, $captcha_token));
+}

clientside_validation_form/clientside_validation_form.module

@@ -226,7 +226,7 @@ function clientside_validation_regular($form_id, $element, &$js_rules, $form_sta
           $title = _clientside_validation_set_title(isset($element['captcha_widgets']['captcha_response']['#title']) ? $element['captcha_widgets']['captcha_response']['#title'] : $element['#name']);
           $message = t('Wrong answer for !title', array('!title' => $title));
           $case_sensitive = strpos($element['#captcha_validate'], 'insensitive') === FALSE;
-          _clientside_validation_set_captcha($element['captcha_widgets']['captcha_response']['#name'], $title, $element['#captcha_validate'], $js_rules, $message);
+          _clientside_validation_set_captcha($element['captcha_widgets']['captcha_response']['#name'], $title, $element['#captcha_validate'], $js_rules, $message, $element['captcha_token']['#value']);
         }
         break;
     }

clientside_validation_webform/clientside_validation_webform.module

@@ -124,7 +124,7 @@ function clientside_validation_webform_after_build_recurse($form_id, &$form, &$f
           $title = _clientside_validation_set_title(isset($element['captcha_widgets']['captcha_response']['#title']) ? $element['captcha_widgets']['captcha_response']['#title'] : $element['#name']);
           $message = t('Wrong answer for !title', array('!title' => $title));
           if (isset($element['captcha_widgets'])) {
-            _clientside_validation_set_captcha($element['captcha_widgets']['captcha_response']['#name'], $title, $element['#captcha_validate'], $js_rules, $message);
+            _clientside_validation_set_captcha($element['captcha_widgets']['captcha_response']['#name'], $title, $element['#captcha_validate'], $js_rules, $message, $element['captcha_token']['#value']);
           }
         }
       }