Adding match user feature.

webform_encrypt.install

+<?php
+
+function webform_encrypt_uninstall() {
+  variable_del('webform_encrypt_match_user');
+}

webform_encrypt.module

@@ -16,6 +16,23 @@ function webform_encrypt_permission() {
  * Implementation of hook_form_alter()
  */
 function webform_encrypt_form_alter(&$form, $form_state, $form_id) {
+  // Add our config options to the webform settings page.
+  if ($form_id == 'webform_admin_settings') {
+    dsm($form);
+    $form['encrypt'] = array(
+      '#type' => 'fieldset',
+      '#title' => t('Webform Encrypt'),
+      '#collapsible' => TRUE,
+      '#collapsed' => FALSE,
+    );
+    $form['encrypt']['webform_encrypt_match_user'] = array(
+      '#type' => 'checkbox',
+      '#title' => t('Enable email to user matching'),
+      '#description' => t('If enabled, every time webform sends an email, it will attempt to find a user that matches the email address the mail will be sent to in order to correctly determine permissions.'),
+      '#default_value' => variable_get('webform_encrypt_match_user', 0),
+    );
+  }
+
   // Add our fields to the component add/edit form.
   if ($form_id == 'webform_component_edit_form') {
 
@@ -69,11 +86,22 @@ function webform_encrypt_webform_submission_presave($node, &$submission) {
  * Decrypt values when displaying webform submissions.
  */
 function webform_encrypt_webform_submission_render_alter(&$renderable) {
+  // First, determine if 1) if we are dealing with an email or a page view, and 2) if user matching
+  // is enabled.
+  if (variable_get('webform_encrypt_match_user', FALSE) && !empty($renderable['#email'])) {
+    // If we are, then try to match a user to the email address we are sending to.
+    $uid = db_query('SELECT uid FROM {users} WHERE mail = ?', array($renderable['#email']['email']))->fetchField();
+    $account = $uid ? user_load($uid) : NULL;
+  } else {
+    $account = NULL;
+  }
+
+  // Next, we loop through components and decrypt as necessary.
   foreach ($renderable['#submission']->data as $cid => $entry) {
     if (isset($renderable['#node']->webform['components'][$cid]['extra']['encrypt']) &&
         $renderable['#node']->webform['components'][$cid]['extra']['encrypt']) {
       $form_key = $renderable['#node']->webform['components'][$cid]['form_key'];
-      if (user_access('view encrypted values')) {
+      if (user_access('view encrypted values', $account)) {
         $renderable[$form_key]['#value'] = decrypt($entry['value'][0], array('base64' => TRUE));
       } else {
         $renderable[$form_key]['#value'] = t('[Value Encrypted]');