Drush policy.

policy.drush.inc

<?php

/**
 * @file
 * Drush policy.
 */

/**
 * Implements drush_hook_COMMAND_validate().
 */
function drush_policy_sql_sync_validate($source = NULL, $destination = NULL) {
  if (strpos( $destination, 'prod') !== FALSE) {
    return drush_set_error(dt('Blocked by drush policy: dont overwrite the production DB.'));
  }
}

/**
 * Implements drush_hook_COMMAND_validate().
 */
function drush_policy_rsync_validate($source = NULL, $destination = NULL) {
  if (strpos($destination, 'prod') !== FALSE) {
    return drush_set_error(dt('Blocked by drush policy: dont overwrite the production files.'));
  }
}