framework/main/classes/crypto/class_CryptoHelper.php

   1 <?php
   2 // Own namespace
   3 namespace CoreFramework\Helper\Crypto;
   4
   5 // Import framework stuff
   6 use CoreFramework\Crypto\Cryptable;
   7 use CoreFramework\Factory\ObjectFactory;
   8 use CoreFramework\Object\BaseFrameworkSystem;
   9
  10 /**
  11  * A helper class for cryptographical things like hashing passwords and so on
  12  *
  13  * @author              Roland Haeder <webmaster@shipsimu.org>
  14  * @version             0.0.0
  15  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2017 Core Developer Team
  16  * @license             GNU GPL 3.0 or any newer version
  17  * @link                http://www.shipsimu.org
  18  *
  19  * This program is free software: you can redistribute it and/or modify
  20  * it under the terms of the GNU General Public License as published by
  21  * the Free Software Foundation, either version 3 of the License, or
  22  * (at your option) any later version.
  23  *
  24  * This program is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  31  */
  32 class CryptoHelper extends BaseFrameworkSystem implements Cryptable {
  33         // Exception constants
  34         const EXCEPTION_ENCRYPT_MISSING = 0x1f0;
  35         const EXCEPTION_ENCRYPT_INVALID = 0x1f1;
  36
  37         /**
  38          * An instance of this own clas
  39          */
  40         private static $selfInstance = NULL;
  41
  42         /**
  43          * Instance of the crypto stream
  44          */
  45         private $cryptoStreamInstance = NULL;
  46
  47         /**
  48          * Salt for hashing operations
  49          */
  50         private $salt = '';
  51
  52         /**
  53          * Protected constructor
  54          *
  55          * @return      void
  56          */
  57         protected function __construct () {
  58                 // Call parent constructor
  59                 parent::__construct(__CLASS__);
  60         }
  61
  62         /**
  63          * Creates an instance of this class
  64          *
  65          * @return      $cryptoInstance         An instance of this crypto helper class
  66          */
  67         public static final function createCryptoHelper () {
  68                 // Get a new instance
  69                 $cryptoInstance = new CryptoHelper();
  70
  71                 // Initialize the hasher
  72                 $cryptoInstance->initHasher();
  73
  74                 // Attach a crypto stream
  75                 $cryptoInstance->attachCryptoStream();
  76
  77                 // Return the instance
  78                 return $cryptoInstance;
  79         }
  80
  81         /**
  82          * Get a singleton instance of this class
  83          *
  84          * @return      $selfInstance   An instance of this crypto helper class
  85          */
  86         public static final function getSelfInstance () {
  87                 // Is no instance there?
  88                 if (is_null(self::$selfInstance)) {
  89                         // Then get a new one
  90                         self::$selfInstance = self::createCryptoHelper();
  91                 } // END - if
  92
  93                 // Return the instance
  94                 return self::$selfInstance;
  95         }
  96
  97         /**
  98          * Attaches a crypto stream to this crypto helper by detecting loaded
  99          * modules.
 100          *
 101          * @return      void
 102          */
 103         protected function attachCryptoStream () {
 104                 // Do we have mcrypt loaded?
 105                 if ($this->isPhpExtensionLoaded('mcrypt')) {
 106                         // Then use it
 107                         $this->cryptoStreamInstance = ObjectFactory::createObjectByName('McryptStream', array($this->getRngInstance()));
 108                 } else {
 109                         // If nothing works ...
 110                         $this->cryptoStreamInstance = ObjectFactory::createObjectByName('NullCryptoStream');
 111                 }
 112         }
 113
 114         /**
 115          * Initializes the hasher for different purposes.
 116          *
 117          * @return      void
 118          */
 119         protected function initHasher () {
 120                 // Initialize the random number generator which is required by some crypto methods
 121                 $this->setRngInstance(ObjectFactory::createObjectByConfiguredName('rng_class'));
 122
 123                 // Generate a salt for the hasher
 124                 $this->generateSalt();
 125         }
 126
 127         /**
 128          * Generates the salt based on configured length
 129          *
 130          * @return      void
 131          */
 132         private function generateSalt () {
 133                 // Get a random string from the RNG
 134                 $randomString = $this->getRngInstance()->randomString() . $this->createUuid();
 135
 136                 // Get config entry for salt length
 137                 $length = $this->getConfigInstance()->getConfigEntry('salt_length');
 138
 139                 // Keep only defined number of characters
 140                 $this->salt = substr(sha1($randomString), -$length, $length);
 141         }
 142
 143         /**
 144          * Returns a UUID (Universal Unique IDentifier) if PECL extension uuid was
 145          * found or an empty string it not.
 146          *
 147          * @return      $uuid   UUID with leading dash or empty string
 148          */
 149         public function createUuid () {
 150                 // Init empty UUID
 151                 $uuid = '';
 152
 153                 // Is the UUID extension loaded and enabled? (see pecl)
 154                 if ($this->getConfigInstance()->getConfigEntry('extension_uuid_loaded') === TRUE) {
 155                         // Then add it as well
 156                         $uuid = uuid_create();
 157                 } // END - if
 158
 159                 // Return it
 160                 return $uuid;
 161         }
 162
 163         /**
 164          * Hashes a string with salt and returns the hash. If an old previous hash
 165          * is supplied the method will use the first X chars of that hash for hashing
 166          * the password. This is useful if you want to check if password is identical
 167          * for authorization purposes.
 168          *
 169          * @param       $str            Unhashed string
 170          * @param       $oldHash        A hash from previous hashed string
 171          * @param       $withFixed      Whether to include a fixed salt (not recommended in p2p applications)
 172          * @return      $hashed         The hashed and salted string
 173          */
 174         public function hashString ($str, $oldHash = '', $withFixed = TRUE) {
 175                 // Cast the string
 176                 $str = (string) $str;
 177
 178                 // Default is the default salt ;-)
 179                 $salt = $this->salt;
 180
 181                 // Is the old password set?
 182                 if (!empty($oldHash)) {
 183                         // Use the salt from hash, first get length
 184                         $length = $this->getConfigInstance()->getConfigEntry('salt_length');
 185
 186                         // Then extract the X first characters from the hash as our salt
 187                         $salt = substr($oldHash, 0, $length);
 188                 } // END - if
 189
 190                 // Hash the password with salt
 191                 //* DEBUG: */ echo "salt=".$salt."/plain=".$str."<br />\n";
 192                 if ($withFixed === TRUE) {
 193                         // Use additional fixed salt
 194                         $hashed = $salt . md5(sprintf($this->getConfigInstance()->getConfigEntry('hash_extra_mask'),
 195                                 $salt,
 196                                 $this->getRngInstance()->getFixedSalt(),
 197                                 $str
 198                         ));
 199                 } else {
 200                         // Use salt+string to hash
 201                         $hashed = $salt . md5(sprintf($this->getConfigInstance()->getConfigEntry('hash_normal_mask'),
 202                                 $salt,
 203                                 $str
 204                         ));
 205                 }
 206
 207                 // And return it
 208                 return $hashed;
 209         }
 210
 211         /**
 212          * Encrypt the string with fixed salt
 213          *
 214          * @param       $str            The unencrypted string
 215          * @param       $key            Optional key, if none provided, a random key will be generated
 216          * @return      $encrypted      Encrypted string
 217          */
 218         public function encryptString ($str, $key = NULL) {
 219                 // Encrypt the string through the stream
 220                 $encrypted = $this->cryptoStreamInstance->encryptStream($str, $key);
 221
 222                 // Return the string
 223                 return $encrypted;
 224         }
 225
 226         /**
 227          * Decrypt the string with fixed salt
 228          *
 229          * @param       $encrypted      Encrypted string
 230          * @return      $str            The unencrypted string
 231          */
 232         public function decryptString ($encrypted) {
 233                 // Encrypt the string through the stream
 234                 $str = $this->cryptoStreamInstance->decryptStream($encrypted);
 235
 236                 // Return the string
 237                 return $str;
 238         }
 239
 240 }