<?php
declare(strict_types=1);
namespace ParagonIE\Halite;
use ParagonIE\Halite\Alerts as CryptoException;
use ParagonIE\Halite\Contract;
/**
* Symmetric Key Crypography uses one secret key, while Asymmetric Key Cryptography
* uses a secret key and public key pair
*/
abstract class Key implements Contract\KeyInterface
{
// FLAGS:
const SECRET_KEY = 1;
const PUBLIC_KEY = 2;
const ENCRYPTION = 4;
const SIGNATURE = 8;
const ASYMMETRIC = 16;
// ALIAS:
const AUTHENTICATION = 8;
// SHORTCUTS:
const CRYPTO_SECRETBOX = 5;
const CRYPTO_AUTH = 9;
const CRYPTO_BOX = 20;
const CRYPTO_SIGN = 24;
private $is_public_key = false;
private $is_signing_key = false;
private $is_asymmetric_key = false;
private $key_material = '';
/**
* Don't let this ever succeed
*
* @throws CryptoException\CannotCloneKey
*/
public function __clone()
{
throw new CryptoException\CannotCloneKey;
}
/**
* @param string $keyMaterial - The actual key data
* @param bool $public - Is this a public key?
* @param bool $signing - Is this a signing key?
* @param bool $asymmetric - Is this being used in asymmetric cryptography?
*/
public function __construct(
string $keyMaterial = '',
...$args
) {
// Workaround: Inherited classes have simpler constructors:
$public = \count($args) >= 1 ? $args[0] : false;
$signing = \count($args) >= 2 ? $args[1] : false;
$asymmetric = \count($args) >= 3 ? $args[2] : false;
// String concatenation used to undo a PHP 7 optimization that causes
// the wrong memory to get overwritten by \Sodium\memzero:
$this->key_material .= $keyMaterial;
$this->is_public_key = $public;
$this->is_signing_key = $signing;
if ($public && !$asymmetric) {
// This is implied.
$asymmetric = true;
}
$this->is_asymmetric_key = $asymmetric;
}
/**
* Hide this from var_dump(), etc.
*
* @return array
*/
public function __debugInfo()
{
// We exclude $this->key_material
return [
'is_asymmetric_key' => $this->is_asymmetric_key,
'is_public_key' => $this->is_public_key,
'is_signing_key' => $this->is_signing_key
];
}
/**
* Make sure you wipe the key from memory on destruction
*/
public function __destruct()
{
if (!$this->is_public_key) {
\Sodium\memzero($this->key_material);
$this->key_material = null;
}
}
/**
* Don't allow this object to ever be serialized
*/
public function __sleep()
{
throw new CryptoException\CannotSerializeKey;
}
/**
* Get public keys
*
* @return string
*/
public function __toString()
{
if ($this->is_public_key) {
return $this->key_material;
}
return '';
}
/**
* Get the actual key material
*
* @return string
*/
public function get()
{
return ''.$this->key_material;
}
/**
* Is this a part of a key pair?
*
* @return bool
*/
public function isAsymmetricKey()
{
return $this->is_asymmetric_key;
}
/**
* Is this a signing key?
*
* @return bool
*/
public function isEncryptionKey()
{
return !$this->is_signing_key;
}
/**
* Is this a public key?
*
* @return bool
*/
public function isPublicKey()
{
return $this->is_public_key;
}
/**
* Is this a secret key?
*
* @return bool
*/
public function isSecretKey()
{
return !$this->is_public_key;
}
/**
* Is this a signing key?
*
* @return bool
*/
public function isSigningKey()
{
return $this->is_signing_key;
}
/**
* Does this integer contain this flag?
*
* @param int $int
* @param int $flag
* @return bool
*/
public static function hasFlag(int $int, int $flag): bool
{
return ($int & $flag) !== 0;
}
/**
* Opposite of hasFlag()
*
* @param int $int
* @param int $flag
* @return bool
*/
public static function doesNotHaveFlag(int $int, int $flag): bool
{
return ($int & $flag) === 0;
}
}
|
Download
