[Summary view] [Print] [Text view]

   1  <?php
   2  
   3  declare(strict_types=1);
   4  
   5  /*
   6   * The MIT License (MIT)
   7   *
   8   * Copyright (c) 2014-2019 Spomky-Labs
   9   *
  10   * This software may be modified and distributed under the terms
  11   * of the MIT license.  See the LICENSE file for details.
  12   */
  13  
  14  namespace Webauthn\Util;
  15  
  16  use Cose\Algorithm\Signature\ECDSA;
  17  use Cose\Algorithm\Signature\Signature;
  18  
  19  /**
  20   * This class fixes the signature of the ECDSA based algorithms.
  21   *
  22   * @internal
  23   *
  24   * @see https://www.w3.org/TR/webauthn/#signature-attestation-types
  25   */
  26  abstract class CoseSignatureFixer
  27  {
  28      public static function fix(string $signature, Signature $algorithm): string
  29      {
  30          switch ($algorithm::identifier()) {
  31              case ECDSA\ES256K::ID:
  32              case ECDSA\ES256::ID:
  33                  if (64 === mb_strlen($signature, '8bit')) {
  34                      return $signature;
  35                  }
  36  
  37                  return ECDSA\ECSignature::fromAsn1($signature, 64); //TODO: fix this hardcoded value by adding a dedicated method for the algorithms
  38              case ECDSA\ES384::ID:
  39                  if (96 === mb_strlen($signature, '8bit')) {
  40                      return $signature;
  41                  }
  42  
  43                  return ECDSA\ECSignature::fromAsn1($signature, 96);
  44              case ECDSA\ES512::ID:
  45                  if (132 === mb_strlen($signature, '8bit')) {
  46                      return $signature;
  47                  }
  48  
  49                  return ECDSA\ECSignature::fromAsn1($signature, 132);
  50          }
  51  
  52          return $signature;
  53      }
  54  }