PhutilOpaqueEnvelopeKey.php
4f9915ecac81stable

PhutilOpaqueEnvelopeKey.php
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			<?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 {

			private static $key;


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


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


			/**
			* @task internal
			*/
			public static function getKey() {
			if (self::$key === null) {
			try {
			self::$key = Filesystem::readRandomBytes(128);
			} catch (Exception $ex) {

			// NOTE: We can't throw here! Otherwise we might get a stack trace
			// including the string that was passed to PhutilOpaqueEnvelope's
			// constructor. Just die() instead.

			die(
			"Unable to read random bytes in PhutilOpaqueEnvelope. (This ".
			"causes an immediate process exit to avoid leaking the envelope ".
			"contents in a stack trace.)");
			}
			}
			return self::$key;
			}

			}