X-Git-Url: https://scripts.mit.edu/gitweb/autoinstallsdev/mediawiki.git/blobdiff_plain/19e297c21b10b1b8a3acad5e73fc71dcb35db44a..6932310fd58ebef145fa01eb76edf7150284d8ea:/vendor/firebase/php-jwt/src/JWT.php diff --git a/vendor/firebase/php-jwt/src/JWT.php b/vendor/firebase/php-jwt/src/JWT.php new file mode 100644 index 00000000..6d30e941 --- /dev/null +++ b/vendor/firebase/php-jwt/src/JWT.php @@ -0,0 +1,370 @@ + + * @author Anant Narayanan + * @license http://opensource.org/licenses/BSD-3-Clause 3-clause BSD + * @link https://github.com/firebase/php-jwt + */ +class JWT +{ + + /** + * When checking nbf, iat or expiration times, + * we want to provide some extra leeway time to + * account for clock skew. + */ + public static $leeway = 0; + + /** + * Allow the current timestamp to be specified. + * Useful for fixing a value within unit testing. + * + * Will default to PHP time() value if null. + */ + public static $timestamp = null; + + public static $supported_algs = array( + 'HS256' => array('hash_hmac', 'SHA256'), + 'HS512' => array('hash_hmac', 'SHA512'), + 'HS384' => array('hash_hmac', 'SHA384'), + 'RS256' => array('openssl', 'SHA256'), + ); + + /** + * Decodes a JWT string into a PHP object. + * + * @param string $jwt The JWT + * @param string|array $key The key, or map of keys. + * If the algorithm used is asymmetric, this is the public key + * @param array $allowed_algs List of supported verification algorithms + * Supported algorithms are 'HS256', 'HS384', 'HS512' and 'RS256' + * + * @return object The JWT's payload as a PHP object + * + * @throws UnexpectedValueException Provided JWT was invalid + * @throws SignatureInvalidException Provided JWT was invalid because the signature verification failed + * @throws BeforeValidException Provided JWT is trying to be used before it's eligible as defined by 'nbf' + * @throws BeforeValidException Provided JWT is trying to be used before it's been created as defined by 'iat' + * @throws ExpiredException Provided JWT has since expired, as defined by the 'exp' claim + * + * @uses jsonDecode + * @uses urlsafeB64Decode + */ + public static function decode($jwt, $key, $allowed_algs = array()) + { + $timestamp = is_null(static::$timestamp) ? time() : static::$timestamp; + + if (empty($key)) { + throw new InvalidArgumentException('Key may not be empty'); + } + if (!is_array($allowed_algs)) { + throw new InvalidArgumentException('Algorithm not allowed'); + } + $tks = explode('.', $jwt); + if (count($tks) != 3) { + throw new UnexpectedValueException('Wrong number of segments'); + } + list($headb64, $bodyb64, $cryptob64) = $tks; + if (null === ($header = static::jsonDecode(static::urlsafeB64Decode($headb64)))) { + throw new UnexpectedValueException('Invalid header encoding'); + } + if (null === $payload = static::jsonDecode(static::urlsafeB64Decode($bodyb64))) { + throw new UnexpectedValueException('Invalid claims encoding'); + } + $sig = static::urlsafeB64Decode($cryptob64); + + if (empty($header->alg)) { + throw new UnexpectedValueException('Empty algorithm'); + } + if (empty(static::$supported_algs[$header->alg])) { + throw new UnexpectedValueException('Algorithm not supported'); + } + if (!in_array($header->alg, $allowed_algs)) { + throw new UnexpectedValueException('Algorithm not allowed'); + } + if (is_array($key) || $key instanceof \ArrayAccess) { + if (isset($header->kid)) { + $key = $key[$header->kid]; + } else { + throw new UnexpectedValueException('"kid" empty, unable to lookup correct key'); + } + } + + // Check the signature + if (!static::verify("$headb64.$bodyb64", $sig, $key, $header->alg)) { + throw new SignatureInvalidException('Signature verification failed'); + } + + // Check if the nbf if it is defined. This is the time that the + // token can actually be used. If it's not yet that time, abort. + if (isset($payload->nbf) && $payload->nbf > ($timestamp + static::$leeway)) { + throw new BeforeValidException( + 'Cannot handle token prior to ' . date(DateTime::ISO8601, $payload->nbf) + ); + } + + // Check that this token has been created before 'now'. This prevents + // using tokens that have been created for later use (and haven't + // correctly used the nbf claim). + if (isset($payload->iat) && $payload->iat > ($timestamp + static::$leeway)) { + throw new BeforeValidException( + 'Cannot handle token prior to ' . date(DateTime::ISO8601, $payload->iat) + ); + } + + // Check if this token has expired. + if (isset($payload->exp) && ($timestamp - static::$leeway) >= $payload->exp) { + throw new ExpiredException('Expired token'); + } + + return $payload; + } + + /** + * Converts and signs a PHP object or array into a JWT string. + * + * @param object|array $payload PHP object or array + * @param string $key The secret key. + * If the algorithm used is asymmetric, this is the private key + * @param string $alg The signing algorithm. + * Supported algorithms are 'HS256', 'HS384', 'HS512' and 'RS256' + * @param mixed $keyId + * @param array $head An array with header elements to attach + * + * @return string A signed JWT + * + * @uses jsonEncode + * @uses urlsafeB64Encode + */ + public static function encode($payload, $key, $alg = 'HS256', $keyId = null, $head = null) + { + $header = array('typ' => 'JWT', 'alg' => $alg); + if ($keyId !== null) { + $header['kid'] = $keyId; + } + if ( isset($head) && is_array($head) ) { + $header = array_merge($head, $header); + } + $segments = array(); + $segments[] = static::urlsafeB64Encode(static::jsonEncode($header)); + $segments[] = static::urlsafeB64Encode(static::jsonEncode($payload)); + $signing_input = implode('.', $segments); + + $signature = static::sign($signing_input, $key, $alg); + $segments[] = static::urlsafeB64Encode($signature); + + return implode('.', $segments); + } + + /** + * Sign a string with a given key and algorithm. + * + * @param string $msg The message to sign + * @param string|resource $key The secret key + * @param string $alg The signing algorithm. + * Supported algorithms are 'HS256', 'HS384', 'HS512' and 'RS256' + * + * @return string An encrypted message + * + * @throws DomainException Unsupported algorithm was specified + */ + public static function sign($msg, $key, $alg = 'HS256') + { + if (empty(static::$supported_algs[$alg])) { + throw new DomainException('Algorithm not supported'); + } + list($function, $algorithm) = static::$supported_algs[$alg]; + switch($function) { + case 'hash_hmac': + return hash_hmac($algorithm, $msg, $key, true); + case 'openssl': + $signature = ''; + $success = openssl_sign($msg, $signature, $key, $algorithm); + if (!$success) { + throw new DomainException("OpenSSL unable to sign data"); + } else { + return $signature; + } + } + } + + /** + * Verify a signature with the message, key and method. Not all methods + * are symmetric, so we must have a separate verify and sign method. + * + * @param string $msg The original message (header and body) + * @param string $signature The original signature + * @param string|resource $key For HS*, a string key works. for RS*, must be a resource of an openssl public key + * @param string $alg The algorithm + * + * @return bool + * + * @throws DomainException Invalid Algorithm or OpenSSL failure + */ + private static function verify($msg, $signature, $key, $alg) + { + if (empty(static::$supported_algs[$alg])) { + throw new DomainException('Algorithm not supported'); + } + + list($function, $algorithm) = static::$supported_algs[$alg]; + switch($function) { + case 'openssl': + $success = openssl_verify($msg, $signature, $key, $algorithm); + if (!$success) { + throw new DomainException("OpenSSL unable to verify data: " . openssl_error_string()); + } else { + return $signature; + } + case 'hash_hmac': + default: + $hash = hash_hmac($algorithm, $msg, $key, true); + if (function_exists('hash_equals')) { + return hash_equals($signature, $hash); + } + $len = min(static::safeStrlen($signature), static::safeStrlen($hash)); + + $status = 0; + for ($i = 0; $i < $len; $i++) { + $status |= (ord($signature[$i]) ^ ord($hash[$i])); + } + $status |= (static::safeStrlen($signature) ^ static::safeStrlen($hash)); + + return ($status === 0); + } + } + + /** + * Decode a JSON string into a PHP object. + * + * @param string $input JSON string + * + * @return object Object representation of JSON string + * + * @throws DomainException Provided string was invalid JSON + */ + public static function jsonDecode($input) + { + if (version_compare(PHP_VERSION, '5.4.0', '>=') && !(defined('JSON_C_VERSION') && PHP_INT_SIZE > 4)) { + /** In PHP >=5.4.0, json_decode() accepts an options parameter, that allows you + * to specify that large ints (like Steam Transaction IDs) should be treated as + * strings, rather than the PHP default behaviour of converting them to floats. + */ + $obj = json_decode($input, false, 512, JSON_BIGINT_AS_STRING); + } else { + /** Not all servers will support that, however, so for older versions we must + * manually detect large ints in the JSON string and quote them (thus converting + *them to strings) before decoding, hence the preg_replace() call. + */ + $max_int_length = strlen((string) PHP_INT_MAX) - 1; + $json_without_bigints = preg_replace('/:\s*(-?\d{'.$max_int_length.',})/', ': "$1"', $input); + $obj = json_decode($json_without_bigints); + } + + if (function_exists('json_last_error') && $errno = json_last_error()) { + static::handleJsonError($errno); + } elseif ($obj === null && $input !== 'null') { + throw new DomainException('Null result with non-null input'); + } + return $obj; + } + + /** + * Encode a PHP object into a JSON string. + * + * @param object|array $input A PHP object or array + * + * @return string JSON representation of the PHP object or array + * + * @throws DomainException Provided object could not be encoded to valid JSON + */ + public static function jsonEncode($input) + { + $json = json_encode($input); + if (function_exists('json_last_error') && $errno = json_last_error()) { + static::handleJsonError($errno); + } elseif ($json === 'null' && $input !== null) { + throw new DomainException('Null result with non-null input'); + } + return $json; + } + + /** + * Decode a string with URL-safe Base64. + * + * @param string $input A Base64 encoded string + * + * @return string A decoded string + */ + public static function urlsafeB64Decode($input) + { + $remainder = strlen($input) % 4; + if ($remainder) { + $padlen = 4 - $remainder; + $input .= str_repeat('=', $padlen); + } + return base64_decode(strtr($input, '-_', '+/')); + } + + /** + * Encode a string with URL-safe Base64. + * + * @param string $input The string you want encoded + * + * @return string The base64 encode of what you passed in + */ + public static function urlsafeB64Encode($input) + { + return str_replace('=', '', strtr(base64_encode($input), '+/', '-_')); + } + + /** + * Helper method to create a JSON error. + * + * @param int $errno An error number from json_last_error() + * + * @return void + */ + private static function handleJsonError($errno) + { + $messages = array( + JSON_ERROR_DEPTH => 'Maximum stack depth exceeded', + JSON_ERROR_CTRL_CHAR => 'Unexpected control character found', + JSON_ERROR_SYNTAX => 'Syntax error, malformed JSON' + ); + throw new DomainException( + isset($messages[$errno]) + ? $messages[$errno] + : 'Unknown JSON error: ' . $errno + ); + } + + /** + * Get the number of bytes in cryptographic strings. + * + * @param string + * + * @return int + */ + private static function safeStrlen($str) + { + if (function_exists('mb_strlen')) { + return mb_strlen($str, '8bit'); + } + return strlen($str); + } +}