mirror of
				https://github.com/yiisoft/yii2.git
				synced 2025-11-04 06:37:55 +08:00 
			
		
		
		
	
		
			
				
	
	
		
			694 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
			
		
		
	
	
			694 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
<?php
 | 
						|
/**
 | 
						|
 * @link http://www.yiiframework.com/
 | 
						|
 * @copyright Copyright (c) 2008 Yii Software LLC
 | 
						|
 * @license http://www.yiiframework.com/license/
 | 
						|
 */
 | 
						|
 | 
						|
namespace yii\base;
 | 
						|
 | 
						|
use Yii;
 | 
						|
use yii\helpers\StringHelper;
 | 
						|
 | 
						|
/**
 | 
						|
 * Security provides a set of methods to handle common security-related tasks.
 | 
						|
 *
 | 
						|
 * In particular, Security supports the following features:
 | 
						|
 *
 | 
						|
 * - Encryption/decryption: [[encryptByKey()]], [[decryptByKey()]], [[encryptByPassword()]] and [[decryptByPassword()]]
 | 
						|
 * - Key derivation using standard algorithms: [[pbkdf2()]] and [[hkdf()]]
 | 
						|
 * - Data tampering prevention: [[hashData()]] and [[validateData()]]
 | 
						|
 * - Password validation: [[generatePasswordHash()]] and [[validatePassword()]]
 | 
						|
 *
 | 
						|
 * > Note: this class requires 'OpenSSL' PHP extension for random key/string generation on Windows and
 | 
						|
 * for encryption/decryption on all platforms. For the highest security level PHP version >= 5.5.0 is recommended.
 | 
						|
 *
 | 
						|
 * For more details and usage information on Security, see the [guide article on security](guide:security-overview).
 | 
						|
 *
 | 
						|
 * @author Qiang Xue <qiang.xue@gmail.com>
 | 
						|
 * @author Tom Worster <fsb@thefsb.org>
 | 
						|
 * @author Klimov Paul <klimov.paul@gmail.com>
 | 
						|
 * @since 2.0
 | 
						|
 */
 | 
						|
class Security extends Component
 | 
						|
{
 | 
						|
    /**
 | 
						|
     * @var string The cipher to use for encryption and decryption.
 | 
						|
     */
 | 
						|
    public $cipher = 'AES-128-CBC';
 | 
						|
    /**
 | 
						|
     * @var array[] Look-up table of block sizes and key sizes for each supported OpenSSL cipher.
 | 
						|
     *
 | 
						|
     * In each element, the key is one of the ciphers supported by OpenSSL (@see openssl_get_cipher_methods()).
 | 
						|
     * The value is an array of two integers, the first is the cipher's block size in bytes and the second is
 | 
						|
     * the key size in bytes.
 | 
						|
     *
 | 
						|
     * > Warning: All OpenSSL ciphers that we recommend are in the default value, i.e. AES in CBC mode.
 | 
						|
     *
 | 
						|
     * > Note: Yii's encryption protocol uses the same size for cipher key, HMAC signature key and key
 | 
						|
     * derivation salt.
 | 
						|
     */
 | 
						|
    public $allowedCiphers = [
 | 
						|
        'AES-128-CBC' => [16, 16],
 | 
						|
        'AES-192-CBC' => [16, 24],
 | 
						|
        'AES-256-CBC' => [16, 32],
 | 
						|
    ];
 | 
						|
    /**
 | 
						|
     * @var string Hash algorithm for key derivation. Recommend sha256, sha384 or sha512.
 | 
						|
     * @see [hash_algos()](https://secure.php.net/manual/en/function.hash-algos.php)
 | 
						|
     */
 | 
						|
    public $kdfHash = 'sha256';
 | 
						|
    /**
 | 
						|
     * @var string Hash algorithm for message authentication. Recommend sha256, sha384 or sha512.
 | 
						|
     * @see [hash_algos()](https://secure.php.net/manual/en/function.hash-algos.php)
 | 
						|
     */
 | 
						|
    public $macHash = 'sha256';
 | 
						|
    /**
 | 
						|
     * @var string HKDF info value for derivation of message authentication key.
 | 
						|
     * @see hkdf()
 | 
						|
     */
 | 
						|
    public $authKeyInfo = 'AuthorizationKey';
 | 
						|
    /**
 | 
						|
     * @var int derivation iterations count.
 | 
						|
     * Set as high as possible to hinder dictionary password attacks.
 | 
						|
     */
 | 
						|
    public $derivationIterations = 100000;
 | 
						|
    /**
 | 
						|
     * @var string strategy, which should be used to generate password hash.
 | 
						|
     * Available strategies:
 | 
						|
     * - 'password_hash' - use of PHP `password_hash()` function with PASSWORD_DEFAULT algorithm.
 | 
						|
     *   This option is recommended, but it requires PHP version >= 5.5.0
 | 
						|
     * - 'crypt' - use PHP `crypt()` function.
 | 
						|
     * @deprecated since version 2.0.7, [[generatePasswordHash()]] ignores [[passwordHashStrategy]] and
 | 
						|
     * uses `password_hash()` when available or `crypt()` when not.
 | 
						|
     */
 | 
						|
    public $passwordHashStrategy;
 | 
						|
    /**
 | 
						|
     * @var int Default cost used for password hashing.
 | 
						|
     * Allowed value is between 4 and 31.
 | 
						|
     * @see generatePasswordHash()
 | 
						|
     * @since 2.0.6
 | 
						|
     */
 | 
						|
    public $passwordHashCost = 13;
 | 
						|
 | 
						|
    /**
 | 
						|
     * @var boolean if LibreSSL should be used.
 | 
						|
     * The recent (> 2.1.5) LibreSSL RNGs are faster and likely better than /dev/urandom.
 | 
						|
     */
 | 
						|
    private $_useLibreSSL;
 | 
						|
 | 
						|
 | 
						|
    /**
 | 
						|
     * @return bool if LibreSSL should be used
 | 
						|
     * Use version is 2.1.5 or higher.
 | 
						|
     * @since 2.0.36
 | 
						|
     */
 | 
						|
    protected function shouldUseLibreSSL()
 | 
						|
    {
 | 
						|
        if ($this->_useLibreSSL === null) {
 | 
						|
            // Parse OPENSSL_VERSION_TEXT because OPENSSL_VERSION_NUMBER is no use for LibreSSL.
 | 
						|
            // https://bugs.php.net/bug.php?id=71143
 | 
						|
            $this->_useLibreSSL = defined('OPENSSL_VERSION_TEXT')
 | 
						|
                && preg_match('{^LibreSSL (\d\d?)\.(\d\d?)\.(\d\d?)$}', OPENSSL_VERSION_TEXT, $matches)
 | 
						|
                && (10000 * $matches[1]) + (100 * $matches[2]) + $matches[3] >= 20105;
 | 
						|
        }
 | 
						|
 | 
						|
        return $this->_useLibreSSL;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Encrypts data using a password.
 | 
						|
     * Derives keys for encryption and authentication from the password using PBKDF2 and a random salt,
 | 
						|
     * which is deliberately slow to protect against dictionary attacks. Use [[encryptByKey()]] to
 | 
						|
     * encrypt fast using a cryptographic key rather than a password. Key derivation time is
 | 
						|
     * determined by [[$derivationIterations]], which should be set as high as possible.
 | 
						|
     * The encrypted data includes a keyed message authentication code (MAC) so there is no need
 | 
						|
     * to hash input or output data.
 | 
						|
     * > Note: Avoid encrypting with passwords wherever possible. Nothing can protect against
 | 
						|
     * poor-quality or compromised passwords.
 | 
						|
     * @param string $data the data to encrypt
 | 
						|
     * @param string $password the password to use for encryption
 | 
						|
     * @return string the encrypted data as byte string
 | 
						|
     * @see decryptByPassword()
 | 
						|
     * @see encryptByKey()
 | 
						|
     */
 | 
						|
    public function encryptByPassword($data, $password)
 | 
						|
    {
 | 
						|
        return $this->encrypt($data, true, $password, null);
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Encrypts data using a cryptographic key.
 | 
						|
     * Derives keys for encryption and authentication from the input key using HKDF and a random salt,
 | 
						|
     * which is very fast relative to [[encryptByPassword()]]. The input key must be properly
 | 
						|
     * random -- use [[generateRandomKey()]] to generate keys.
 | 
						|
     * The encrypted data includes a keyed message authentication code (MAC) so there is no need
 | 
						|
     * to hash input or output data.
 | 
						|
     * @param string $data the data to encrypt
 | 
						|
     * @param string $inputKey the input to use for encryption and authentication
 | 
						|
     * @param string $info optional context and application specific information, see [[hkdf()]]
 | 
						|
     * @return string the encrypted data as byte string
 | 
						|
     * @see decryptByKey()
 | 
						|
     * @see encryptByPassword()
 | 
						|
     */
 | 
						|
    public function encryptByKey($data, $inputKey, $info = null)
 | 
						|
    {
 | 
						|
        return $this->encrypt($data, false, $inputKey, $info);
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Verifies and decrypts data encrypted with [[encryptByPassword()]].
 | 
						|
     * @param string $data the encrypted data to decrypt
 | 
						|
     * @param string $password the password to use for decryption
 | 
						|
     * @return bool|string the decrypted data or false on authentication failure
 | 
						|
     * @see encryptByPassword()
 | 
						|
     */
 | 
						|
    public function decryptByPassword($data, $password)
 | 
						|
    {
 | 
						|
        return $this->decrypt($data, true, $password, null);
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Verifies and decrypts data encrypted with [[encryptByKey()]].
 | 
						|
     * @param string $data the encrypted data to decrypt
 | 
						|
     * @param string $inputKey the input to use for encryption and authentication
 | 
						|
     * @param string $info optional context and application specific information, see [[hkdf()]]
 | 
						|
     * @return bool|string the decrypted data or false on authentication failure
 | 
						|
     * @see encryptByKey()
 | 
						|
     */
 | 
						|
    public function decryptByKey($data, $inputKey, $info = null)
 | 
						|
    {
 | 
						|
        return $this->decrypt($data, false, $inputKey, $info);
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Encrypts data.
 | 
						|
     *
 | 
						|
     * @param string $data data to be encrypted
 | 
						|
     * @param bool $passwordBased set true to use password-based key derivation
 | 
						|
     * @param string $secret the encryption password or key
 | 
						|
     * @param string|null $info context/application specific information, e.g. a user ID
 | 
						|
     * See [RFC 5869 Section 3.2](https://tools.ietf.org/html/rfc5869#section-3.2) for more details.
 | 
						|
     *
 | 
						|
     * @return string the encrypted data as byte string
 | 
						|
     * @throws InvalidConfigException on OpenSSL not loaded
 | 
						|
     * @throws Exception on OpenSSL error
 | 
						|
     * @see decrypt()
 | 
						|
     */
 | 
						|
    protected function encrypt($data, $passwordBased, $secret, $info)
 | 
						|
    {
 | 
						|
        if (!extension_loaded('openssl')) {
 | 
						|
            throw new InvalidConfigException('Encryption requires the OpenSSL PHP extension');
 | 
						|
        }
 | 
						|
        if (!isset($this->allowedCiphers[$this->cipher][0], $this->allowedCiphers[$this->cipher][1])) {
 | 
						|
            throw new InvalidConfigException($this->cipher . ' is not an allowed cipher');
 | 
						|
        }
 | 
						|
 | 
						|
        list($blockSize, $keySize) = $this->allowedCiphers[$this->cipher];
 | 
						|
 | 
						|
        $keySalt = $this->generateRandomKey($keySize);
 | 
						|
        if ($passwordBased) {
 | 
						|
            $key = $this->pbkdf2($this->kdfHash, $secret, $keySalt, $this->derivationIterations, $keySize);
 | 
						|
        } else {
 | 
						|
            $key = $this->hkdf($this->kdfHash, $secret, $keySalt, $info, $keySize);
 | 
						|
        }
 | 
						|
 | 
						|
        $iv = $this->generateRandomKey($blockSize);
 | 
						|
 | 
						|
        $encrypted = openssl_encrypt($data, $this->cipher, $key, OPENSSL_RAW_DATA, $iv);
 | 
						|
        if ($encrypted === false) {
 | 
						|
            throw new \yii\base\Exception('OpenSSL failure on encryption: ' . openssl_error_string());
 | 
						|
        }
 | 
						|
 | 
						|
        $authKey = $this->hkdf($this->kdfHash, $key, null, $this->authKeyInfo, $keySize);
 | 
						|
        $hashed = $this->hashData($iv . $encrypted, $authKey);
 | 
						|
 | 
						|
        /*
 | 
						|
         * Output: [keySalt][MAC][IV][ciphertext]
 | 
						|
         * - keySalt is KEY_SIZE bytes long
 | 
						|
         * - MAC: message authentication code, length same as the output of MAC_HASH
 | 
						|
         * - IV: initialization vector, length $blockSize
 | 
						|
         */
 | 
						|
        return $keySalt . $hashed;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Decrypts data.
 | 
						|
     *
 | 
						|
     * @param string $data encrypted data to be decrypted.
 | 
						|
     * @param bool $passwordBased set true to use password-based key derivation
 | 
						|
     * @param string $secret the decryption password or key
 | 
						|
     * @param string|null $info context/application specific information, @see encrypt()
 | 
						|
     *
 | 
						|
     * @return bool|string the decrypted data or false on authentication failure
 | 
						|
     * @throws InvalidConfigException on OpenSSL not loaded
 | 
						|
     * @throws Exception on OpenSSL error
 | 
						|
     * @see encrypt()
 | 
						|
     */
 | 
						|
    protected function decrypt($data, $passwordBased, $secret, $info)
 | 
						|
    {
 | 
						|
        if (!extension_loaded('openssl')) {
 | 
						|
            throw new InvalidConfigException('Encryption requires the OpenSSL PHP extension');
 | 
						|
        }
 | 
						|
        if (!isset($this->allowedCiphers[$this->cipher][0], $this->allowedCiphers[$this->cipher][1])) {
 | 
						|
            throw new InvalidConfigException($this->cipher . ' is not an allowed cipher');
 | 
						|
        }
 | 
						|
 | 
						|
        list($blockSize, $keySize) = $this->allowedCiphers[$this->cipher];
 | 
						|
 | 
						|
        $keySalt = StringHelper::byteSubstr($data, 0, $keySize);
 | 
						|
        if ($passwordBased) {
 | 
						|
            $key = $this->pbkdf2($this->kdfHash, $secret, $keySalt, $this->derivationIterations, $keySize);
 | 
						|
        } else {
 | 
						|
            $key = $this->hkdf($this->kdfHash, $secret, $keySalt, $info, $keySize);
 | 
						|
        }
 | 
						|
 | 
						|
        $authKey = $this->hkdf($this->kdfHash, $key, null, $this->authKeyInfo, $keySize);
 | 
						|
        $data = $this->validateData(StringHelper::byteSubstr($data, $keySize, null), $authKey);
 | 
						|
        if ($data === false) {
 | 
						|
            return false;
 | 
						|
        }
 | 
						|
 | 
						|
        $iv = StringHelper::byteSubstr($data, 0, $blockSize);
 | 
						|
        $encrypted = StringHelper::byteSubstr($data, $blockSize, null);
 | 
						|
 | 
						|
        $decrypted = openssl_decrypt($encrypted, $this->cipher, $key, OPENSSL_RAW_DATA, $iv);
 | 
						|
        if ($decrypted === false) {
 | 
						|
            throw new \yii\base\Exception('OpenSSL failure on decryption: ' . openssl_error_string());
 | 
						|
        }
 | 
						|
 | 
						|
        return $decrypted;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Derives a key from the given input key using the standard HKDF algorithm.
 | 
						|
     * Implements HKDF specified in [RFC 5869](https://tools.ietf.org/html/rfc5869).
 | 
						|
     * Recommend use one of the SHA-2 hash algorithms: sha224, sha256, sha384 or sha512.
 | 
						|
     * @param string $algo a hash algorithm supported by `hash_hmac()`, e.g. 'SHA-256'
 | 
						|
     * @param string $inputKey the source key
 | 
						|
     * @param string $salt the random salt
 | 
						|
     * @param string $info optional info to bind the derived key material to application-
 | 
						|
     * and context-specific information, e.g. a user ID or API version, see
 | 
						|
     * [RFC 5869](https://tools.ietf.org/html/rfc5869)
 | 
						|
     * @param int $length length of the output key in bytes. If 0, the output key is
 | 
						|
     * the length of the hash algorithm output.
 | 
						|
     * @throws InvalidArgumentException when HMAC generation fails.
 | 
						|
     * @return string the derived key
 | 
						|
     */
 | 
						|
    public function hkdf($algo, $inputKey, $salt = null, $info = null, $length = 0)
 | 
						|
    {
 | 
						|
        if (function_exists('hash_hkdf')) {
 | 
						|
            $outputKey = hash_hkdf($algo, $inputKey, $length, $info, $salt);
 | 
						|
            if ($outputKey === false) {
 | 
						|
                throw new InvalidArgumentException('Invalid parameters to hash_hkdf()');
 | 
						|
            }
 | 
						|
 | 
						|
            return $outputKey;
 | 
						|
        }
 | 
						|
 | 
						|
        $test = @hash_hmac($algo, '', '', true);
 | 
						|
        if (!$test) {
 | 
						|
            throw new InvalidArgumentException('Failed to generate HMAC with hash algorithm: ' . $algo);
 | 
						|
        }
 | 
						|
        $hashLength = StringHelper::byteLength($test);
 | 
						|
        if (is_string($length) && preg_match('{^\d{1,16}$}', $length)) {
 | 
						|
            $length = (int) $length;
 | 
						|
        }
 | 
						|
        if (!is_int($length) || $length < 0 || $length > 255 * $hashLength) {
 | 
						|
            throw new InvalidArgumentException('Invalid length');
 | 
						|
        }
 | 
						|
        $blocks = $length !== 0 ? ceil($length / $hashLength) : 1;
 | 
						|
 | 
						|
        if ($salt === null) {
 | 
						|
            $salt = str_repeat("\0", $hashLength);
 | 
						|
        }
 | 
						|
        $prKey = hash_hmac($algo, $inputKey, $salt, true);
 | 
						|
 | 
						|
        $hmac = '';
 | 
						|
        $outputKey = '';
 | 
						|
        for ($i = 1; $i <= $blocks; $i++) {
 | 
						|
            $hmac = hash_hmac($algo, $hmac . $info . chr($i), $prKey, true);
 | 
						|
            $outputKey .= $hmac;
 | 
						|
        }
 | 
						|
 | 
						|
        if ($length !== 0) {
 | 
						|
            $outputKey = StringHelper::byteSubstr($outputKey, 0, $length);
 | 
						|
        }
 | 
						|
 | 
						|
        return $outputKey;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Derives a key from the given password using the standard PBKDF2 algorithm.
 | 
						|
     * Implements HKDF2 specified in [RFC 2898](http://tools.ietf.org/html/rfc2898#section-5.2)
 | 
						|
     * Recommend use one of the SHA-2 hash algorithms: sha224, sha256, sha384 or sha512.
 | 
						|
     * @param string $algo a hash algorithm supported by `hash_hmac()`, e.g. 'SHA-256'
 | 
						|
     * @param string $password the source password
 | 
						|
     * @param string $salt the random salt
 | 
						|
     * @param int $iterations the number of iterations of the hash algorithm. Set as high as
 | 
						|
     * possible to hinder dictionary password attacks.
 | 
						|
     * @param int $length length of the output key in bytes. If 0, the output key is
 | 
						|
     * the length of the hash algorithm output.
 | 
						|
     * @return string the derived key
 | 
						|
     * @throws InvalidArgumentException when hash generation fails due to invalid params given.
 | 
						|
     */
 | 
						|
    public function pbkdf2($algo, $password, $salt, $iterations, $length = 0)
 | 
						|
    {
 | 
						|
        if (function_exists('hash_pbkdf2') && PHP_VERSION_ID >= 50500) {
 | 
						|
            $outputKey = hash_pbkdf2($algo, $password, $salt, $iterations, $length, true);
 | 
						|
            if ($outputKey === false) {
 | 
						|
                throw new InvalidArgumentException('Invalid parameters to hash_pbkdf2()');
 | 
						|
            }
 | 
						|
 | 
						|
            return $outputKey;
 | 
						|
        }
 | 
						|
 | 
						|
        // todo: is there a nice way to reduce the code repetition in hkdf() and pbkdf2()?
 | 
						|
        $test = @hash_hmac($algo, '', '', true);
 | 
						|
        if (!$test) {
 | 
						|
            throw new InvalidArgumentException('Failed to generate HMAC with hash algorithm: ' . $algo);
 | 
						|
        }
 | 
						|
        if (is_string($iterations) && preg_match('{^\d{1,16}$}', $iterations)) {
 | 
						|
            $iterations = (int) $iterations;
 | 
						|
        }
 | 
						|
        if (!is_int($iterations) || $iterations < 1) {
 | 
						|
            throw new InvalidArgumentException('Invalid iterations');
 | 
						|
        }
 | 
						|
        if (is_string($length) && preg_match('{^\d{1,16}$}', $length)) {
 | 
						|
            $length = (int) $length;
 | 
						|
        }
 | 
						|
        if (!is_int($length) || $length < 0) {
 | 
						|
            throw new InvalidArgumentException('Invalid length');
 | 
						|
        }
 | 
						|
        $hashLength = StringHelper::byteLength($test);
 | 
						|
        $blocks = $length !== 0 ? ceil($length / $hashLength) : 1;
 | 
						|
 | 
						|
        $outputKey = '';
 | 
						|
        for ($j = 1; $j <= $blocks; $j++) {
 | 
						|
            $hmac = hash_hmac($algo, $salt . pack('N', $j), $password, true);
 | 
						|
            $xorsum = $hmac;
 | 
						|
            for ($i = 1; $i < $iterations; $i++) {
 | 
						|
                $hmac = hash_hmac($algo, $hmac, $password, true);
 | 
						|
                $xorsum ^= $hmac;
 | 
						|
            }
 | 
						|
            $outputKey .= $xorsum;
 | 
						|
        }
 | 
						|
 | 
						|
        if ($length !== 0) {
 | 
						|
            $outputKey = StringHelper::byteSubstr($outputKey, 0, $length);
 | 
						|
        }
 | 
						|
 | 
						|
        return $outputKey;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Prefixes data with a keyed hash value so that it can later be detected if it is tampered.
 | 
						|
     * There is no need to hash inputs or outputs of [[encryptByKey()]] or [[encryptByPassword()]]
 | 
						|
     * as those methods perform the task.
 | 
						|
     * @param string $data the data to be protected
 | 
						|
     * @param string $key the secret key to be used for generating hash. Should be a secure
 | 
						|
     * cryptographic key.
 | 
						|
     * @param bool $rawHash whether the generated hash value is in raw binary format. If false, lowercase
 | 
						|
     * hex digits will be generated.
 | 
						|
     * @return string the data prefixed with the keyed hash
 | 
						|
     * @throws InvalidConfigException when HMAC generation fails.
 | 
						|
     * @see validateData()
 | 
						|
     * @see generateRandomKey()
 | 
						|
     * @see hkdf()
 | 
						|
     * @see pbkdf2()
 | 
						|
     */
 | 
						|
    public function hashData($data, $key, $rawHash = false)
 | 
						|
    {
 | 
						|
        $hash = hash_hmac($this->macHash, $data, $key, $rawHash);
 | 
						|
        if (!$hash) {
 | 
						|
            throw new InvalidConfigException('Failed to generate HMAC with hash algorithm: ' . $this->macHash);
 | 
						|
        }
 | 
						|
 | 
						|
        return $hash . $data;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Validates if the given data is tampered.
 | 
						|
     * @param string $data the data to be validated. The data must be previously
 | 
						|
     * generated by [[hashData()]].
 | 
						|
     * @param string $key the secret key that was previously used to generate the hash for the data in [[hashData()]].
 | 
						|
     * function to see the supported hashing algorithms on your system. This must be the same
 | 
						|
     * as the value passed to [[hashData()]] when generating the hash for the data.
 | 
						|
     * @param bool $rawHash this should take the same value as when you generate the data using [[hashData()]].
 | 
						|
     * It indicates whether the hash value in the data is in binary format. If false, it means the hash value consists
 | 
						|
     * of lowercase hex digits only.
 | 
						|
     * hex digits will be generated.
 | 
						|
     * @return string|false the real data with the hash stripped off. False if the data is tampered.
 | 
						|
     * @throws InvalidConfigException when HMAC generation fails.
 | 
						|
     * @see hashData()
 | 
						|
     */
 | 
						|
    public function validateData($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;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * 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');
 | 
						|
        }
 | 
						|
 | 
						|
        return random_bytes($length);
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * 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);
 | 
						|
    }
 | 
						|
}
 |