781 lines
32 KiB
PHP
781 lines
32 KiB
PHP
<?php
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/**
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* @link http://www.yiiframework.com/
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* @copyright Copyright (c) 2008 Yii Software LLC
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* @license http://www.yiiframework.com/license/
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*/
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namespace yii\base;
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use Yii;
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use yii\helpers\StringHelper;
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/**
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* Security provides a set of methods to handle common security-related tasks.
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*
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* In particular, Security supports the following features:
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*
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* - Encryption/decryption: [[encryptByKey()]], [[decryptByKey()]], [[encryptByPassword()]] and [[decryptByPassword()]]
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* - Key derivation using standard algorithms: [[pbkdf2()]] and [[hkdf()]]
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* - Data tampering prevention: [[hashData()]] and [[validateData()]]
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* - Password validation: [[generatePasswordHash()]] and [[validatePassword()]]
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*
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* > Note: this class requires 'OpenSSL' PHP extension for random key/string generation on Windows and
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* for encryption/decryption on all platforms. For the highest security level PHP version >= 5.5.0 is recommended.
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*
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* For more details and usage information on Security, see the [guide article on security](guide:security-overview).
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*
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* @author Qiang Xue <qiang.xue@gmail.com>
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* @author Tom Worster <fsb@thefsb.org>
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* @author Klimov Paul <klimov.paul@gmail.com>
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* @since 2.0
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*/
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class Security extends Component
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{
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/**
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* @var string The cipher to use for encryption and decryption.
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*/
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public $cipher = 'AES-128-CBC';
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/**
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* @var array[] Look-up table of block sizes and key sizes for each supported OpenSSL cipher.
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*
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* In each element, the key is one of the ciphers supported by OpenSSL (@see openssl_get_cipher_methods()).
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* The value is an array of two integers, the first is the cipher's block size in bytes and the second is
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* the key size in bytes.
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*
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* > Warning: All OpenSSL ciphers that we recommend are in the default value, i.e. AES in CBC mode.
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*
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* > Note: Yii's encryption protocol uses the same size for cipher key, HMAC signature key and key
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* derivation salt.
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*/
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public $allowedCiphers = [
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'AES-128-CBC' => [16, 16],
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'AES-192-CBC' => [16, 24],
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'AES-256-CBC' => [16, 32],
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];
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/**
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* @var string Hash algorithm for key derivation. Recommend sha256, sha384 or sha512.
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* @see [hash_algos()](https://secure.php.net/manual/en/function.hash-algos.php)
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*/
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public $kdfHash = 'sha256';
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/**
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* @var string Hash algorithm for message authentication. Recommend sha256, sha384 or sha512.
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* @see [hash_algos()](https://secure.php.net/manual/en/function.hash-algos.php)
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*/
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public $macHash = 'sha256';
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/**
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* @var string HKDF info value for derivation of message authentication key.
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* @see hkdf()
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*/
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public $authKeyInfo = 'AuthorizationKey';
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/**
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* @var int derivation iterations count.
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* Set as high as possible to hinder dictionary password attacks.
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*/
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public $derivationIterations = 100000;
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/**
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* @var string strategy, which should be used to generate password hash.
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* Available strategies:
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* - 'password_hash' - use of PHP `password_hash()` function with PASSWORD_DEFAULT algorithm.
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* This option is recommended, but it requires PHP version >= 5.5.0
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* - 'crypt' - use PHP `crypt()` function.
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* @deprecated since version 2.0.7, [[generatePasswordHash()]] ignores [[passwordHashStrategy]] and
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* uses `password_hash()` when available or `crypt()` when not.
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*/
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public $passwordHashStrategy;
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/**
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* @var int Default cost used for password hashing.
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* Allowed value is between 4 and 31.
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* @see generatePasswordHash()
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* @since 2.0.6
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*/
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public $passwordHashCost = 13;
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/**
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* @var boolean if LibreSSL should be used.
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* The recent (> 2.1.5) LibreSSL RNGs are faster and likely better than /dev/urandom.
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*/
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private $_useLibreSSL;
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/**
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* @return bool if LibreSSL should be used
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* Use version is 2.1.5 or higher.
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* @since 2.0.36
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*/
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protected function shouldUseLibreSSL()
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{
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if ($this->_useLibreSSL === null) {
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// Parse OPENSSL_VERSION_TEXT because OPENSSL_VERSION_NUMBER is no use for LibreSSL.
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// https://bugs.php.net/bug.php?id=71143
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$this->_useLibreSSL = defined('OPENSSL_VERSION_TEXT')
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&& preg_match('{^LibreSSL (\d\d?)\.(\d\d?)\.(\d\d?)$}', OPENSSL_VERSION_TEXT, $matches)
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&& (10000 * $matches[1]) + (100 * $matches[2]) + $matches[3] >= 20105;
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}
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return $this->_useLibreSSL;
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}
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/**
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* @return bool if operating system is Windows
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*/
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private function isWindows()
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{
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return DIRECTORY_SEPARATOR !== '/';
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}
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/**
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* Encrypts data using a password.
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* Derives keys for encryption and authentication from the password using PBKDF2 and a random salt,
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* which is deliberately slow to protect against dictionary attacks. Use [[encryptByKey()]] to
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* encrypt fast using a cryptographic key rather than a password. Key derivation time is
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* determined by [[$derivationIterations]], which should be set as high as possible.
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* The encrypted data includes a keyed message authentication code (MAC) so there is no need
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* to hash input or output data.
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* > Note: Avoid encrypting with passwords wherever possible. Nothing can protect against
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* poor-quality or compromised passwords.
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* @param string $data the data to encrypt
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* @param string $password the password to use for encryption
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* @return string the encrypted data as byte string
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* @see decryptByPassword()
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* @see encryptByKey()
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*/
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public function encryptByPassword($data, $password)
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{
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return $this->encrypt($data, true, $password, null);
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}
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/**
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* Encrypts data using a cryptographic key.
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* Derives keys for encryption and authentication from the input key using HKDF and a random salt,
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* which is very fast relative to [[encryptByPassword()]]. The input key must be properly
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* random -- use [[generateRandomKey()]] to generate keys.
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* The encrypted data includes a keyed message authentication code (MAC) so there is no need
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* to hash input or output data.
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* @param string $data the data to encrypt
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* @param string $inputKey the input to use for encryption and authentication
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* @param string $info optional context and application specific information, see [[hkdf()]]
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* @return string the encrypted data as byte string
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* @see decryptByKey()
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* @see encryptByPassword()
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*/
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public function encryptByKey($data, $inputKey, $info = null)
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{
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return $this->encrypt($data, false, $inputKey, $info);
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}
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/**
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* Verifies and decrypts data encrypted with [[encryptByPassword()]].
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* @param string $data the encrypted data to decrypt
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* @param string $password the password to use for decryption
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* @return bool|string the decrypted data or false on authentication failure
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* @see encryptByPassword()
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*/
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public function decryptByPassword($data, $password)
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{
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return $this->decrypt($data, true, $password, null);
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}
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/**
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* Verifies and decrypts data encrypted with [[encryptByKey()]].
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* @param string $data the encrypted data to decrypt
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* @param string $inputKey the input to use for encryption and authentication
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* @param string $info optional context and application specific information, see [[hkdf()]]
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* @return bool|string the decrypted data or false on authentication failure
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* @see encryptByKey()
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*/
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public function decryptByKey($data, $inputKey, $info = null)
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{
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return $this->decrypt($data, false, $inputKey, $info);
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}
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/**
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* Encrypts data.
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*
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* @param string $data data to be encrypted
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* @param bool $passwordBased set true to use password-based key derivation
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* @param string $secret the encryption password or key
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* @param string|null $info context/application specific information, e.g. a user ID
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* See [RFC 5869 Section 3.2](https://tools.ietf.org/html/rfc5869#section-3.2) for more details.
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*
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* @return string the encrypted data as byte string
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* @throws InvalidConfigException on OpenSSL not loaded
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* @throws Exception on OpenSSL error
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* @see decrypt()
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*/
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protected function encrypt($data, $passwordBased, $secret, $info)
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{
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if (!extension_loaded('openssl')) {
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throw new InvalidConfigException('Encryption requires the OpenSSL PHP extension');
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}
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if (!isset($this->allowedCiphers[$this->cipher][0], $this->allowedCiphers[$this->cipher][1])) {
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throw new InvalidConfigException($this->cipher . ' is not an allowed cipher');
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}
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list($blockSize, $keySize) = $this->allowedCiphers[$this->cipher];
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$keySalt = $this->generateRandomKey($keySize);
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if ($passwordBased) {
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$key = $this->pbkdf2($this->kdfHash, $secret, $keySalt, $this->derivationIterations, $keySize);
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} else {
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$key = $this->hkdf($this->kdfHash, $secret, $keySalt, $info, $keySize);
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}
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$iv = $this->generateRandomKey($blockSize);
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$encrypted = openssl_encrypt($data, $this->cipher, $key, OPENSSL_RAW_DATA, $iv);
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if ($encrypted === false) {
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throw new \yii\base\Exception('OpenSSL failure on encryption: ' . openssl_error_string());
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}
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$authKey = $this->hkdf($this->kdfHash, $key, null, $this->authKeyInfo, $keySize);
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$hashed = $this->hashData($iv . $encrypted, $authKey);
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/*
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* Output: [keySalt][MAC][IV][ciphertext]
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* - keySalt is KEY_SIZE bytes long
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* - MAC: message authentication code, length same as the output of MAC_HASH
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* - IV: initialization vector, length $blockSize
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*/
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return $keySalt . $hashed;
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}
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/**
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* Decrypts data.
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*
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* @param string $data encrypted data to be decrypted.
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* @param bool $passwordBased set true to use password-based key derivation
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* @param string $secret the decryption password or key
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* @param string|null $info context/application specific information, @see encrypt()
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*
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* @return bool|string the decrypted data or false on authentication failure
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* @throws InvalidConfigException on OpenSSL not loaded
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* @throws Exception on OpenSSL error
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* @see encrypt()
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*/
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protected function decrypt($data, $passwordBased, $secret, $info)
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{
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if (!extension_loaded('openssl')) {
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throw new InvalidConfigException('Encryption requires the OpenSSL PHP extension');
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}
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if (!isset($this->allowedCiphers[$this->cipher][0], $this->allowedCiphers[$this->cipher][1])) {
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throw new InvalidConfigException($this->cipher . ' is not an allowed cipher');
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}
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list($blockSize, $keySize) = $this->allowedCiphers[$this->cipher];
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$keySalt = StringHelper::byteSubstr($data, 0, $keySize);
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if ($passwordBased) {
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$key = $this->pbkdf2($this->kdfHash, $secret, $keySalt, $this->derivationIterations, $keySize);
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} else {
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$key = $this->hkdf($this->kdfHash, $secret, $keySalt, $info, $keySize);
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}
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$authKey = $this->hkdf($this->kdfHash, $key, null, $this->authKeyInfo, $keySize);
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$data = $this->validateData(StringHelper::byteSubstr($data, $keySize, null), $authKey);
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if ($data === false) {
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return false;
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}
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$iv = StringHelper::byteSubstr($data, 0, $blockSize);
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$encrypted = StringHelper::byteSubstr($data, $blockSize, null);
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$decrypted = openssl_decrypt($encrypted, $this->cipher, $key, OPENSSL_RAW_DATA, $iv);
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if ($decrypted === false) {
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throw new \yii\base\Exception('OpenSSL failure on decryption: ' . openssl_error_string());
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}
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return $decrypted;
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}
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/**
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* Derives a key from the given input key using the standard HKDF algorithm.
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* Implements HKDF specified in [RFC 5869](https://tools.ietf.org/html/rfc5869).
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* Recommend use one of the SHA-2 hash algorithms: sha224, sha256, sha384 or sha512.
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* @param string $algo a hash algorithm supported by `hash_hmac()`, e.g. 'SHA-256'
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* @param string $inputKey the source key
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* @param string $salt the random salt
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* @param string $info optional info to bind the derived key material to application-
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* and context-specific information, e.g. a user ID or API version, see
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* [RFC 5869](https://tools.ietf.org/html/rfc5869)
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* @param int $length length of the output key in bytes. If 0, the output key is
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* the length of the hash algorithm output.
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* @throws InvalidArgumentException when HMAC generation fails.
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* @return string the derived key
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*/
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public function hkdf($algo, $inputKey, $salt = null, $info = null, $length = 0)
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{
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if (function_exists('hash_hkdf')) {
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$outputKey = hash_hkdf($algo, $inputKey, $length, $info, $salt);
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if ($outputKey === false) {
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throw new InvalidArgumentException('Invalid parameters to hash_hkdf()');
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}
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return $outputKey;
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}
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$test = @hash_hmac($algo, '', '', true);
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if (!$test) {
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throw new InvalidArgumentException('Failed to generate HMAC with hash algorithm: ' . $algo);
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}
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$hashLength = StringHelper::byteLength($test);
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if (is_string($length) && preg_match('{^\d{1,16}$}', $length)) {
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$length = (int) $length;
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}
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if (!is_int($length) || $length < 0 || $length > 255 * $hashLength) {
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throw new InvalidArgumentException('Invalid length');
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}
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$blocks = $length !== 0 ? ceil($length / $hashLength) : 1;
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if ($salt === null) {
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$salt = str_repeat("\0", $hashLength);
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}
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$prKey = hash_hmac($algo, $inputKey, $salt, true);
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$hmac = '';
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$outputKey = '';
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for ($i = 1; $i <= $blocks; $i++) {
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$hmac = hash_hmac($algo, $hmac . $info . chr($i), $prKey, true);
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$outputKey .= $hmac;
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}
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if ($length !== 0) {
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$outputKey = StringHelper::byteSubstr($outputKey, 0, $length);
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}
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return $outputKey;
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}
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/**
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* Derives a key from the given password using the standard PBKDF2 algorithm.
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* Implements HKDF2 specified in [RFC 2898](http://tools.ietf.org/html/rfc2898#section-5.2)
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* Recommend use one of the SHA-2 hash algorithms: sha224, sha256, sha384 or sha512.
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* @param string $algo a hash algorithm supported by `hash_hmac()`, e.g. 'SHA-256'
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* @param string $password the source password
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* @param string $salt the random salt
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* @param int $iterations the number of iterations of the hash algorithm. Set as high as
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* possible to hinder dictionary password attacks.
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* @param int $length length of the output key in bytes. If 0, the output key is
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* the length of the hash algorithm output.
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* @return string the derived key
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* @throws InvalidArgumentException when hash generation fails due to invalid params given.
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*/
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public function pbkdf2($algo, $password, $salt, $iterations, $length = 0)
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{
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if (function_exists('hash_pbkdf2') && PHP_VERSION_ID >= 50500) {
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$outputKey = hash_pbkdf2($algo, $password, $salt, $iterations, $length, true);
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if ($outputKey === false) {
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throw new InvalidArgumentException('Invalid parameters to hash_pbkdf2()');
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}
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return $outputKey;
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}
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// todo: is there a nice way to reduce the code repetition in hkdf() and pbkdf2()?
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$test = @hash_hmac($algo, '', '', true);
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if (!$test) {
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throw new InvalidArgumentException('Failed to generate HMAC with hash algorithm: ' . $algo);
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}
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if (is_string($iterations) && preg_match('{^\d{1,16}$}', $iterations)) {
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$iterations = (int) $iterations;
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}
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if (!is_int($iterations) || $iterations < 1) {
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throw new InvalidArgumentException('Invalid iterations');
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}
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if (is_string($length) && preg_match('{^\d{1,16}$}', $length)) {
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$length = (int) $length;
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}
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if (!is_int($length) || $length < 0) {
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throw new InvalidArgumentException('Invalid length');
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}
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$hashLength = StringHelper::byteLength($test);
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$blocks = $length !== 0 ? ceil($length / $hashLength) : 1;
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$outputKey = '';
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for ($j = 1; $j <= $blocks; $j++) {
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$hmac = hash_hmac($algo, $salt . pack('N', $j), $password, true);
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$xorsum = $hmac;
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for ($i = 1; $i < $iterations; $i++) {
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$hmac = hash_hmac($algo, $hmac, $password, true);
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$xorsum ^= $hmac;
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}
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$outputKey .= $xorsum;
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}
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if ($length !== 0) {
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$outputKey = StringHelper::byteSubstr($outputKey, 0, $length);
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}
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return $outputKey;
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}
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/**
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* Prefixes data with a keyed hash value so that it can later be detected if it is tampered.
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* There is no need to hash inputs or outputs of [[encryptByKey()]] or [[encryptByPassword()]]
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* as those methods perform the task.
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* @param string $data the data to be protected
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* @param string $key the secret key to be used for generating hash. Should be a secure
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* cryptographic key.
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* @param bool $rawHash whether the generated hash value is in raw binary format. If false, lowercase
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* hex digits will be generated.
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* @return string the data prefixed with the keyed hash
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* @throws InvalidConfigException when HMAC generation fails.
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* @see validateData()
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* @see generateRandomKey()
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* @see hkdf()
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* @see pbkdf2()
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*/
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public function hashData($data, $key, $rawHash = false)
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{
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$hash = hash_hmac($this->macHash, $data, $key, $rawHash);
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if (!$hash) {
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throw new InvalidConfigException('Failed to generate HMAC with hash algorithm: ' . $this->macHash);
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}
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return $hash . $data;
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}
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/**
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* Validates if the given data is tampered.
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* @param string $data the data to be validated. The data must be previously
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* generated by [[hashData()]].
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* @param string $key the secret key that was previously used to generate the hash for the data in [[hashData()]].
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* function to see the supported hashing algorithms on your system. This must be the same
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* as the value passed to [[hashData()]] when generating the hash for the data.
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* @param bool $rawHash this should take the same value as when you generate the data using [[hashData()]].
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* It indicates whether the hash value in the data is in binary format. If false, it means the hash value consists
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* of lowercase hex digits only.
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* hex digits will be generated.
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* @return string|false the real data with the hash stripped off. False if the data is tampered.
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* @throws InvalidConfigException when HMAC generation fails.
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* @see hashData()
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*/
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public function validateData($data, $key, $rawHash = false)
|
|
{
|
|
$test = @hash_hmac($this->macHash, '', '', $rawHash);
|
|
if (!$test) {
|
|
throw new InvalidConfigException('Failed to generate HMAC with hash algorithm: ' . $this->macHash);
|
|
}
|
|
$hashLength = StringHelper::byteLength($test);
|
|
if (StringHelper::byteLength($data) >= $hashLength) {
|
|
$hash = StringHelper::byteSubstr($data, 0, $hashLength);
|
|
$pureData = StringHelper::byteSubstr($data, $hashLength, null);
|
|
|
|
$calculatedHash = hash_hmac($this->macHash, $pureData, $key, $rawHash);
|
|
|
|
if ($this->compareString($hash, $calculatedHash)) {
|
|
return $pureData;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
private $_randomFile;
|
|
|
|
/**
|
|
* Generates specified number of random bytes.
|
|
* Note that output may not be ASCII.
|
|
* @see generateRandomString() if you need a string.
|
|
*
|
|
* @param int $length the number of bytes to generate
|
|
* @return string the generated random bytes
|
|
* @throws InvalidArgumentException if wrong length is specified
|
|
* @throws Exception on failure.
|
|
*/
|
|
public function generateRandomKey($length = 32)
|
|
{
|
|
if (!is_int($length)) {
|
|
throw new InvalidArgumentException('First parameter ($length) must be an integer');
|
|
}
|
|
|
|
if ($length < 1) {
|
|
throw new InvalidArgumentException('First parameter ($length) must be greater than 0');
|
|
}
|
|
|
|
// always use random_bytes() if it is available
|
|
if (function_exists('random_bytes')) {
|
|
return random_bytes($length);
|
|
}
|
|
|
|
// The recent LibreSSL RNGs are faster and likely better than /dev/urandom.
|
|
// Since 5.4.0, openssl_random_pseudo_bytes() reads from CryptGenRandom on Windows instead
|
|
// of using OpenSSL library. LibreSSL is OK everywhere but don't use OpenSSL on non-Windows.
|
|
if (function_exists('openssl_random_pseudo_bytes')
|
|
&& ($this->shouldUseLibreSSL() || $this->isWindows())
|
|
) {
|
|
$key = openssl_random_pseudo_bytes($length, $cryptoStrong);
|
|
if ($cryptoStrong === false) {
|
|
throw new Exception(
|
|
'openssl_random_pseudo_bytes() set $crypto_strong false. Your PHP setup is insecure.'
|
|
);
|
|
}
|
|
if ($key !== false && StringHelper::byteLength($key) === $length) {
|
|
return $key;
|
|
}
|
|
}
|
|
|
|
// mcrypt_create_iv() does not use libmcrypt. Since PHP 5.3.7 it directly reads
|
|
// CryptGenRandom on Windows. Elsewhere it directly reads /dev/urandom.
|
|
if (function_exists('mcrypt_create_iv')) {
|
|
$key = mcrypt_create_iv($length, MCRYPT_DEV_URANDOM);
|
|
if (StringHelper::byteLength($key) === $length) {
|
|
return $key;
|
|
}
|
|
}
|
|
|
|
// If not on Windows, try to open a random device.
|
|
if ($this->_randomFile === null && !$this->isWindows()) {
|
|
// urandom is a symlink to random on FreeBSD.
|
|
$device = PHP_OS === 'FreeBSD' ? '/dev/random' : '/dev/urandom';
|
|
// Check random device for special character device protection mode. Use lstat()
|
|
// instead of stat() in case an attacker arranges a symlink to a fake device.
|
|
$lstat = @lstat($device);
|
|
if ($lstat !== false && ($lstat['mode'] & 0170000) === 020000) {
|
|
$this->_randomFile = fopen($device, 'rb') ?: null;
|
|
|
|
if (is_resource($this->_randomFile)) {
|
|
// Reduce PHP stream buffer from default 8192 bytes to optimize data
|
|
// transfer from the random device for smaller values of $length.
|
|
// This also helps to keep future randoms out of user memory space.
|
|
$bufferSize = 8;
|
|
|
|
if (function_exists('stream_set_read_buffer')) {
|
|
stream_set_read_buffer($this->_randomFile, $bufferSize);
|
|
}
|
|
// stream_set_read_buffer() isn't implemented on HHVM
|
|
if (function_exists('stream_set_chunk_size')) {
|
|
stream_set_chunk_size($this->_randomFile, $bufferSize);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (is_resource($this->_randomFile)) {
|
|
$buffer = '';
|
|
$stillNeed = $length;
|
|
while ($stillNeed > 0) {
|
|
$someBytes = fread($this->_randomFile, $stillNeed);
|
|
if ($someBytes === false) {
|
|
break;
|
|
}
|
|
$buffer .= $someBytes;
|
|
$stillNeed -= StringHelper::byteLength($someBytes);
|
|
if ($stillNeed === 0) {
|
|
// Leaving file pointer open in order to make next generation faster by reusing it.
|
|
return $buffer;
|
|
}
|
|
}
|
|
fclose($this->_randomFile);
|
|
$this->_randomFile = null;
|
|
}
|
|
|
|
throw new Exception('Unable to generate a random key');
|
|
}
|
|
|
|
/**
|
|
* Generates a random string of specified length.
|
|
* The string generated matches [A-Za-z0-9_-]+ and is transparent to URL-encoding.
|
|
*
|
|
* @param int $length the length of the key in characters
|
|
* @return string the generated random key
|
|
* @throws Exception on failure.
|
|
*/
|
|
public function generateRandomString($length = 32)
|
|
{
|
|
if (!is_int($length)) {
|
|
throw new InvalidArgumentException('First parameter ($length) must be an integer');
|
|
}
|
|
|
|
if ($length < 1) {
|
|
throw new InvalidArgumentException('First parameter ($length) must be greater than 0');
|
|
}
|
|
|
|
$bytes = $this->generateRandomKey($length);
|
|
return substr(StringHelper::base64UrlEncode($bytes), 0, $length);
|
|
}
|
|
|
|
/**
|
|
* Generates a secure hash from a password and a random salt.
|
|
*
|
|
* The generated hash can be stored in database.
|
|
* Later when a password needs to be validated, the hash can be fetched and passed
|
|
* to [[validatePassword()]]. For example,
|
|
*
|
|
* ```php
|
|
* // generates the hash (usually done during user registration or when the password is changed)
|
|
* $hash = Yii::$app->getSecurity()->generatePasswordHash($password);
|
|
* // ...save $hash in database...
|
|
*
|
|
* // during login, validate if the password entered is correct using $hash fetched from database
|
|
* if (Yii::$app->getSecurity()->validatePassword($password, $hash)) {
|
|
* // password is good
|
|
* } else {
|
|
* // password is bad
|
|
* }
|
|
* ```
|
|
*
|
|
* @param string $password The password to be hashed.
|
|
* @param int $cost Cost parameter used by the Blowfish hash algorithm.
|
|
* The higher the value of cost,
|
|
* the longer it takes to generate the hash and to verify a password against it. Higher cost
|
|
* therefore slows down a brute-force attack. For best protection against brute-force attacks,
|
|
* set it to the highest value that is tolerable on production servers. The time taken to
|
|
* compute the hash doubles for every increment by one of $cost.
|
|
* @return string The password hash string. When [[passwordHashStrategy]] is set to 'crypt',
|
|
* the output is always 60 ASCII characters, when set to 'password_hash' the output length
|
|
* might increase in future versions of PHP (https://secure.php.net/manual/en/function.password-hash.php)
|
|
* @throws Exception on bad password parameter or cost parameter.
|
|
* @see validatePassword()
|
|
*/
|
|
public function generatePasswordHash($password, $cost = null)
|
|
{
|
|
if ($cost === null) {
|
|
$cost = $this->passwordHashCost;
|
|
}
|
|
|
|
if (function_exists('password_hash')) {
|
|
/* @noinspection PhpUndefinedConstantInspection */
|
|
return password_hash($password, PASSWORD_DEFAULT, ['cost' => $cost]);
|
|
}
|
|
|
|
$salt = $this->generateSalt($cost);
|
|
$hash = crypt($password, $salt);
|
|
// strlen() is safe since crypt() returns only ascii
|
|
if (!is_string($hash) || strlen($hash) !== 60) {
|
|
throw new Exception('Unknown error occurred while generating hash.');
|
|
}
|
|
|
|
return $hash;
|
|
}
|
|
|
|
/**
|
|
* Verifies a password against a hash.
|
|
* @param string $password The password to verify.
|
|
* @param string $hash The hash to verify the password against.
|
|
* @return bool whether the password is correct.
|
|
* @throws InvalidArgumentException on bad password/hash parameters or if crypt() with Blowfish hash is not available.
|
|
* @see generatePasswordHash()
|
|
*/
|
|
public function validatePassword($password, $hash)
|
|
{
|
|
if (!is_string($password) || $password === '') {
|
|
throw new InvalidArgumentException('Password must be a string and cannot be empty.');
|
|
}
|
|
|
|
if (!preg_match('/^\$2[axy]\$(\d\d)\$[\.\/0-9A-Za-z]{22}/', $hash, $matches)
|
|
|| $matches[1] < 4
|
|
|| $matches[1] > 30
|
|
) {
|
|
throw new InvalidArgumentException('Hash is invalid.');
|
|
}
|
|
|
|
if (function_exists('password_verify')) {
|
|
return password_verify($password, $hash);
|
|
}
|
|
|
|
$test = crypt($password, $hash);
|
|
$n = strlen($test);
|
|
if ($n !== 60) {
|
|
return false;
|
|
}
|
|
|
|
return $this->compareString($test, $hash);
|
|
}
|
|
|
|
/**
|
|
* Generates a salt that can be used to generate a password hash.
|
|
*
|
|
* The PHP [crypt()](https://secure.php.net/manual/en/function.crypt.php) built-in function
|
|
* requires, for the Blowfish hash algorithm, a salt string in a specific format:
|
|
* "$2a$", "$2x$" or "$2y$", a two digit cost parameter, "$", and 22 characters
|
|
* from the alphabet "./0-9A-Za-z".
|
|
*
|
|
* @param int $cost the cost parameter
|
|
* @return string the random salt value.
|
|
* @throws InvalidArgumentException if the cost parameter is out of the range of 4 to 31.
|
|
*/
|
|
protected function generateSalt($cost = 13)
|
|
{
|
|
$cost = (int) $cost;
|
|
if ($cost < 4 || $cost > 31) {
|
|
throw new InvalidArgumentException('Cost must be between 4 and 31.');
|
|
}
|
|
|
|
// Get a 20-byte random string
|
|
$rand = $this->generateRandomKey(20);
|
|
// Form the prefix that specifies Blowfish (bcrypt) algorithm and cost parameter.
|
|
$salt = sprintf('$2y$%02d$', $cost);
|
|
// Append the random salt data in the required base64 format.
|
|
$salt .= str_replace('+', '.', substr(base64_encode($rand), 0, 22));
|
|
|
|
return $salt;
|
|
}
|
|
|
|
/**
|
|
* Performs string comparison using timing attack resistant approach.
|
|
* @see http://codereview.stackexchange.com/questions/13512
|
|
* @param string $expected string to compare.
|
|
* @param string $actual user-supplied string.
|
|
* @return bool whether strings are equal.
|
|
*/
|
|
public function compareString($expected, $actual)
|
|
{
|
|
if (!is_string($expected)) {
|
|
throw new InvalidArgumentException('Expected expected value to be a string, ' . gettype($expected) . ' given.');
|
|
}
|
|
|
|
if (!is_string($actual)) {
|
|
throw new InvalidArgumentException('Expected actual value to be a string, ' . gettype($actual) . ' given.');
|
|
}
|
|
|
|
if (function_exists('hash_equals')) {
|
|
return hash_equals($expected, $actual);
|
|
}
|
|
|
|
$expected .= "\0";
|
|
$actual .= "\0";
|
|
$expectedLength = StringHelper::byteLength($expected);
|
|
$actualLength = StringHelper::byteLength($actual);
|
|
$diff = $expectedLength - $actualLength;
|
|
for ($i = 0; $i < $actualLength; $i++) {
|
|
$diff |= (ord($actual[$i]) ^ ord($expected[$i % $expectedLength]));
|
|
}
|
|
|
|
return $diff === 0;
|
|
}
|
|
|
|
/**
|
|
* Masks a token to make it uncompressible.
|
|
* Applies a random mask to the token and prepends the mask used to the result making the string always unique.
|
|
* Used to mitigate BREACH attack by randomizing how token is outputted on each request.
|
|
* @param string $token An unmasked token.
|
|
* @return string A masked token.
|
|
* @since 2.0.12
|
|
*/
|
|
public function maskToken($token)
|
|
{
|
|
// The number of bytes in a mask is always equal to the number of bytes in a token.
|
|
$mask = $this->generateRandomKey(StringHelper::byteLength($token));
|
|
return StringHelper::base64UrlEncode($mask . ($mask ^ $token));
|
|
}
|
|
|
|
/**
|
|
* Unmasks a token previously masked by `maskToken`.
|
|
* @param string $maskedToken A masked token.
|
|
* @return string An unmasked token, or an empty string in case of token format is invalid.
|
|
* @since 2.0.12
|
|
*/
|
|
public function unmaskToken($maskedToken)
|
|
{
|
|
$decoded = StringHelper::base64UrlDecode($maskedToken);
|
|
$length = StringHelper::byteLength($decoded) / 2;
|
|
// Check if the masked token has an even length.
|
|
if (!is_int($length)) {
|
|
return '';
|
|
}
|
|
|
|
return StringHelper::byteSubstr($decoded, $length, $length) ^ StringHelper::byteSubstr($decoded, 0, $length);
|
|
}
|
|
}
|