verifyCode code does not match a2f code

Question

verifyCode code does not match a2f code

monster-space opened this issue 5 years ago · comments

i use this library but every time i verify code it does not match so i make some changes in library i might wrong some where but these changes gives me 100% changes
`<?php

/**

PHP Class for handling Google Authenticator 2-factor authentication.
@author Michael Kliewe
@license http://www.opensource.org/licenses/bsd-license.php BSD License
@link http://www.phpgangsta.de/
*/
class GoogleAuthenticator
{
protected $_codeLength = 6;

/**
- Create new secret.
- 16 characters, randomly chosen from the allowed base32 characters.
- @param int $secretLength
- @return string
  */
  public function createSecret($secretLength = 16)
  {
  $validChars = $this->_getBase32LookupTable();
  // var_dump($validChars);die;
  // Valid secret lengths are 80 to 640 bits
  if ($secretLength < 16 || $secretLength > 128) {
  throw new Exception('Bad secret length');
  }
  $secret = '';
  $rnd = false;
  if (function_exists('random_bytes') && !empty(random_bytes($secretLength))) {
  $rnd = random_bytes($secretLength);
  } elseif (function_exists('mcrypt_create_iv') && empty(random_bytes($secretLength))) {
  $rnd = mcrypt_create_iv($secretLength, MCRYPT_DEV_URANDOM);
  }
  elseif (function_exists('openssl_random_pseudo_bytes') && empty(mcrypt_create_iv($secretLength, MCRYPT_DEV_URANDOM))) {
  $rnd = openssl_random_pseudo_bytes($secretLength, $cryptoStrong);
  if (!$cryptoStrong) {
  $rnd = false;
  }
  }
  if ($rnd !== false) {
  for ($i = 0; $i < $secretLength; ++$i) {
  $secret .= $validChars[ord($rnd[$i]) & 31];
  }
  } else {
  throw new Exception('No source of secure random');
  }
  
  return $secret;
  }
/**
- Calculate the code, with given secret and point in time.
- @param string $secret
- @param int|null $timeSlice
- @return string
  */
  public function getCode($secret, $timeSlice = null)
  {
  if ($timeSlice === null) {
  $timeSlice = floor(time() / 30);
  }
  
  $secretkey = $this->_base32Decode($secret);
  
  // Pack time into binary string
  $time = chr(0).chr(0).chr(0).chr(0).pack('N*', $timeSlice);
  // Hash it with users secret key
  $hm = hash_hmac('SHA1', $time, $secretkey, true);
  // Use last nipple of result as index/offset
  $offset = ord(substr($hm, -1)) & 0x0F;
  // grab 4 bytes of the result
  $hashpart = substr($hm, $offset, 4);
  
  // Unpak binary value
  $value = unpack('N', $hashpart);
  $value = $value[1];
  // Only 32 bits
  $value = $value & 0x7FFFFFFF;
  
  $modulo = pow(10, $this->_codeLength);
  
  return str_pad($value % $modulo, $this->_codeLength, '0', STR_PAD_LEFT);
  }
/**
- Get QR-Code URL for image, from google charts.
- @param string $name
- @param string $secret
- @param string $title
- @param array $params
- @return string
  */
  public function getQRCodeGoogleUrl($name, $secret, $title = null, $params = array())
  {
  $width = !empty($params['width']) && (int) $params['width'] > 0 ? (int) $params['width'] : 175;
  $height = !empty($params['height']) && (int) $params['height'] > 0 ? (int) $params['height'] : 175;
  $level = !empty($params['level']) && array_search($params['level'], array('L', 'M', 'Q', 'H')) !== false ? $params['level'] : 'H';
  
  $urlencoded = urlencode('otpauth://totp/'.$name.'?secret='.$secret.'');
  if (isset($title)) {
  $urlencoded .= urlencode('&issuer='.urlencode($title));
  }
  
  return 'https://chart.googleapis.com/chart?chs='.$width.'x'.$height.'&chld='.$level.'|0&cht=qr&chl='.$urlencoded.'';
  }
/**
- Check if the code is correct. This will accept codes starting from $discrepancy30sec ago to $discrepancy30sec from now.
- @param string $secret
- @param string $code
- @param int $discrepancy This is the allowed time drift in 30 second units (8 means 4 minutes before or after)
- @param int|null $currentTimeSlice time slice if we want use other that time()
- @return bool
  */
  public function verifyCode($secret, $code, $discrepancy = 1, $currentTimeSlice = null)
  {
  if ($currentTimeSlice === null) {
  $currentTimeSlice = floor(time() / 30);
  }
  // var_export(strlen($code));
  if (strlen($code) < 6) {
  return false;
  }
  
  for ($i = -$discrepancy; $i <= $discrepancy; ++$i) {
  $calculatedCode = $this->getCode($secret, $currentTimeSlice + $i);
  // var_export($this->timingSafeEquals($calculatedCode, $code));
  if ($this->timingSafeEquals($calculatedCode, $code)) {
  return true;
  }
  }
  
  return false;
  }
/**
- Set the code length, should be >=6.
- @param int $length
- @return PHPGangsta_GoogleAuthenticator
  */
  public function setCodeLength($length)
  {
  $this->_codeLength = $length;
  
  return $this;
  }
/**
- Helper class to decode base32.
- @param $secret
- @return bool|string
  */
  protected function _base32Decode($secret)
  {
  if (empty($secret)) {
  return '';
  }
  
  $base32chars = $this->_getBase32LookupTable();
  $base32charsFlipped = array_flip($base32chars);
  
  $paddingCharCount = substr_count($secret, $base32chars[32]);
  $allowedValues = array(6, 4, 3, 1, 0);
  if (!in_array($paddingCharCount, $allowedValues)) {
  return false;
  }
  for ($i = 0; $i < 4; ++$i) {
  if ($paddingCharCount == $allowedValues[$i] &&
  substr($secret, -($allowedValues[$i])) != str_repeat($base32chars[32], $allowedValues[$i])) {
  return false;
  }
  }
  $secret = str_replace('=', '', $secret);
  $secret = str_split($secret);
  $binaryString = '';
  for ($i = 0; $i < count($secret); $i = $i + 8) {
  $x = '';
  if (!in_array($secret[$i], $base32chars)) {
  return false;
  }
  for ($j = 0; $j < 8; ++$j) {
  $x .= str_pad(base_convert(@$base32charsFlipped[@$secret[$i + $j]], 10, 2), 5, '0', STR_PAD_LEFT);
  }
  $eightBits = str_split($x, 8);
  for ($z = 0; $z < count($eightBits); ++$z) {
  $binaryString .= (($y = chr(base_convert($eightBits[$z], 2, 10))) || ord($y) == 48) ? $y : '';
  }
  }
  
  return $binaryString;
  }
/**
- Get array with all 32 characters for decoding from/encoding to base32.
- @return array
  */
  protected function _getBase32LookupTable()
  {
  return array(
  'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', // 7
  'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', // 15
  'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', // 23
  'Y', 'Z', '2', '3', '4', '5', '6', '7', // 31
  '=', // padding char
  );
  }
/**
- A timing safe equals comparison
- more info here: http://blog.ircmaxell.com/2014/11/its-all-about-time.html.
- @param string $safeString The internal (safe) value to be checked
- @param string $userString The user submitted (unsafe) value
- @return bool True if the two strings are identical
  */
  protected function timingSafeEquals($safeString, $userString)
  {
  // if (function_exists('hash_equals')) {
  // return hash_equals($safeString, $userString);
  // }
  
  $safeLen = strlen($safeString);
  $userLen = strlen($userString);
  
  if ($userLen !== $safeLen) {
  return false;
  }
  
  // var_dump($safeLen);
  // var_dump($userLen);die;
  $result = 0;
  
  for ($i = 0; $i < $userLen; ++$i) {
  $result |= (ord($safeString[$i]) ^ ord($userString[$i]));
  }
  
  // They are only identical strings if $result is exactly 0...
  // return $result ===0;
  return $result;
  }
  }
  `