Differential D20980 Diff 49996 src/error/PhutilOpaqueEnvelopeKey.php

Changeset View

Standalone View

				<?php

				/**
				* Holds the key for @{class:PhutilOpaqueEnvelope} in a logically distant
				* location so it will never appear in stack traces, etc. You should never need
				* to use this class directly. See @{class:PhutilOpaqueEnvelope} for
				* information about opaque envelopes.
				*
				* @task internal Internals
				*/
				final class PhutilOpaqueEnvelopeKey extends Phobject {

				private static $key;


				/* -( Internals )---------------------------------------------------------- */


				/**
				* @task internal
				*/
				private function __construct() {
				// <private>
				}


				/**
				* @task internal
				*/
				public static function getKey() {
				if (self::$key === null) {
				// NOTE: We're using a weak random source because cryptographic levels
				// of security aren't terribly important here and it allows us to use
				// envelopes on systems which don't have a strong random source. Notably,
				// this lets us make it to the readability check for `/dev/urandom` in
				// Phabricator on systems where we can't read it.
				self::$key = '';
				for ($ii = 0; $ii < 8; $ii++) {
				self::$key .= md5(mt_rand(), $raw_output = true);
				}
				}
				return self::$key;
				}

				}