yms/validate.php
author Dan Fuhry <dan@enanocms.org>
Wed, 11 Jan 2017 13:02:34 +0000
changeset 12 31387f4022e5
parent 10 351d40b21cbc
permissions -rw-r--r--
Tolerate up to 0.5Hz difference in OTP timestamps I've received complaints of OTP validation failures during the trial rollout at Datto. I dumped a few OTPs along with the times of validation and found that the user's Yubikey was running its oscillator at 8.32Hz. This commit adds tolerance for up to 0.5Hz of variation to the OTP's timestamp field.

<?php

function page_Special_YubikeyValidate()
{
  global $db, $session, $paths, $template, $plugins; // Common objects
  global $do_gzip;
  $do_gzip = false;
  
  // Check parameters
  if ( !isset($_GET['id']) )
  {
    yms_send_reply('MISSING_PARAMETER', '', array('info' => 'id'));
  }
  
  if ( !isset($_GET['otp']) )
  {
    yms_send_reply('MISSING_PARAMETER', '', array('info' => 'otp'));
  }

  $nonce = null;
  if ( isset($_GET['nonce']) )
  {
    $nonce = $_GET['nonce'];
  }
  
  // first, get API key so we can properly sign responses
  $id = intval($_GET['id']);
  $q = $db->sql_query("SELECT apikey FROM " . table_prefix . "yms_clients WHERE id = $id;");
  if ( !$q )
    $db->_die();
  
  if ( $db->numrows($q) < 1 )
    yms_send_reply("NO_SUCH_CLIENT");
  
  list($g_api_key) = $db->fetchrow_num($q);
  $db->free_result($q);
  
  // check API key
  if ( isset($_GET['h']) )
  {
    $hex_api_key = yms_hex_encode(base64_decode($g_api_key));
    $right_sig = yubikey_sign($_GET, $hex_api_key);
    if ( $right_sig !== $_GET['h'] )
    {
      yms_send_reply('BAD_SIGNATURE');
    }
  }
  
  $GLOBALS['g_api_key'] =& $g_api_key;
  
  yms_send_reply(yms_validate_otp($_GET['otp'], $id), '', array('nonce' => $nonce, 'otp' => $_GET['otp']));
}