--- /dev/null
+<?php
+
+namespace Drupal\Component\Utility;
+
+/**
+ * Utility class for cryptographically-secure string handling routines.
+ *
+ * @ingroup utility
+ */
+class Crypt {
+
+ /**
+ * Returns a string of highly randomized bytes (over the full 8-bit range).
+ *
+ * This function is better than simply calling mt_rand() or any other built-in
+ * PHP function because it can return a long string of bytes (compared to < 4
+ * bytes normally from mt_rand()) and uses the best available pseudo-random
+ * source.
+ *
+ * In PHP 7 and up, this uses the built-in PHP function random_bytes().
+ * In older PHP versions, this uses the random_bytes() function provided by
+ * the random_compat library, or the fallback hash-based generator from Drupal
+ * 7.x.
+ *
+ * @param int $count
+ * The number of characters (bytes) to return in the string.
+ *
+ * @return string
+ * A randomly generated string.
+ */
+ public static function randomBytes($count) {
+ try {
+ return random_bytes($count);
+ }
+ catch (\Exception $e) {
+ // $random_state does not use drupal_static as it stores random bytes.
+ static $random_state, $bytes;
+ // If the compatibility library fails, this simple hash-based PRNG will
+ // generate a good set of pseudo-random bytes on any system.
+ // Note that it may be important that our $random_state is passed
+ // through hash() prior to being rolled into $output, that the two hash()
+ // invocations are different, and that the extra input into the first one
+ // - the microtime() - is prepended rather than appended. This is to avoid
+ // directly leaking $random_state via the $output stream, which could
+ // allow for trivial prediction of further "random" numbers.
+ if (strlen($bytes) < $count) {
+ // Initialize on the first call. The $_SERVER variable includes user and
+ // system-specific information that varies a little with each page.
+ if (!isset($random_state)) {
+ $random_state = print_r($_SERVER, TRUE);
+ if (function_exists('getmypid')) {
+ // Further initialize with the somewhat random PHP process ID.
+ $random_state .= getmypid();
+ }
+ $bytes = '';
+ // Ensure mt_rand() is reseeded before calling it the first time.
+ mt_srand();
+ }
+
+ do {
+ $random_state = hash('sha256', microtime() . mt_rand() . $random_state);
+ $bytes .= hash('sha256', mt_rand() . $random_state, TRUE);
+ } while (strlen($bytes) < $count);
+ }
+ $output = substr($bytes, 0, $count);
+ $bytes = substr($bytes, $count);
+ return $output;
+ }
+ }
+
+ /**
+ * Calculates a base-64 encoded, URL-safe sha-256 hmac.
+ *
+ * @param mixed $data
+ * Scalar value to be validated with the hmac.
+ * @param mixed $key
+ * A secret key, this can be any scalar value.
+ *
+ * @return string
+ * A base-64 encoded sha-256 hmac, with + replaced with -, / with _ and
+ * any = padding characters removed.
+ */
+ public static function hmacBase64($data, $key) {
+ // $data and $key being strings here is necessary to avoid empty string
+ // results of the hash function if they are not scalar values. As this
+ // function is used in security-critical contexts like token validation it
+ // is important that it never returns an empty string.
+ if (!is_scalar($data) || !is_scalar($key)) {
+ throw new \InvalidArgumentException('Both parameters passed to \Drupal\Component\Utility\Crypt::hmacBase64 must be scalar values.');
+ }
+
+ $hmac = base64_encode(hash_hmac('sha256', $data, $key, TRUE));
+ // Modify the hmac so it's safe to use in URLs.
+ return str_replace(['+', '/', '='], ['-', '_', ''], $hmac);
+ }
+
+ /**
+ * Calculates a base-64 encoded, URL-safe sha-256 hash.
+ *
+ * @param string $data
+ * String to be hashed.
+ *
+ * @return string
+ * A base-64 encoded sha-256 hash, with + replaced with -, / with _ and
+ * any = padding characters removed.
+ */
+ public static function hashBase64($data) {
+ $hash = base64_encode(hash('sha256', $data, TRUE));
+ // Modify the hash so it's safe to use in URLs.
+ return str_replace(['+', '/', '='], ['-', '_', ''], $hash);
+ }
+
+ /**
+ * Compares strings in constant time.
+ *
+ * @param string $known_string
+ * The expected string.
+ * @param string $user_string
+ * The user supplied string to check.
+ *
+ * @return bool
+ * Returns TRUE when the two strings are equal, FALSE otherwise.
+ */
+ public static function hashEquals($known_string, $user_string) {
+ if (function_exists('hash_equals')) {
+ return hash_equals($known_string, $user_string);
+ }
+ else {
+ // Backport of hash_equals() function from PHP 5.6
+ // @see https://github.com/php/php-src/blob/PHP-5.6/ext/hash/hash.c#L739
+ if (!is_string($known_string)) {
+ trigger_error(sprintf("Expected known_string to be a string, %s given", gettype($known_string)), E_USER_WARNING);
+ return FALSE;
+ }
+
+ if (!is_string($user_string)) {
+ trigger_error(sprintf("Expected user_string to be a string, %s given", gettype($user_string)), E_USER_WARNING);
+ return FALSE;
+ }
+
+ $known_len = strlen($known_string);
+ if ($known_len !== strlen($user_string)) {
+ return FALSE;
+ }
+
+ // This is security sensitive code. Do not optimize this for speed.
+ $result = 0;
+ for ($i = 0; $i < $known_len; $i++) {
+ $result |= (ord($known_string[$i]) ^ ord($user_string[$i]));
+ }
+
+ return $result === 0;
+ }
+ }
+
+ /**
+ * Returns a URL-safe, base64 encoded string of highly randomized bytes.
+ *
+ * @param $count
+ * The number of random bytes to fetch and base64 encode.
+ *
+ * @return string
+ * The base64 encoded result will have a length of up to 4 * $count.
+ *
+ * @see \Drupal\Component\Utility\Crypt::randomBytes()
+ */
+ public static function randomBytesBase64($count = 32) {
+ return str_replace(['+', '/', '='], ['-', '_', ''], base64_encode(static::randomBytes($count)));
+ }
+
+}
projects / yaffs-website / blobdiff