PocketMine-MP/src/network/mcpe/encryption/EncryptionUtils.php
2023-07-14 11:55:47 +01:00

85 lines
2.7 KiB
PHP

<?php
/*
*
* ____ _ _ __ __ _ __ __ ____
* | _ \ ___ ___| | _____| |_| \/ (_)_ __ ___ | \/ | _ \
* | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
* | __/ (_) | (__| < __/ |_| | | | | | | | __/_____| | | | __/
* |_| \___/ \___|_|\_\___|\__|_| |_|_|_| |_|\___| |_| |_|_|
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* @author PocketMine Team
* @link http://www.pocketmine.net/
*
*
*/
declare(strict_types=1);
namespace pocketmine\network\mcpe\encryption;
use pocketmine\network\mcpe\JwtUtils;
use pocketmine\utils\Utils;
use function base64_encode;
use function bin2hex;
use function gmp_init;
use function gmp_strval;
use function hex2bin;
use function openssl_digest;
use function openssl_error_string;
use function openssl_pkey_derive;
use function openssl_pkey_get_details;
use function str_pad;
use const STR_PAD_LEFT;
final class EncryptionUtils{
private function __construct(){
//NOOP
}
private static function validateKey(\OpenSSLAsymmetricKey $key) : void{
$keyDetails = Utils::assumeNotFalse(openssl_pkey_get_details($key));
if(!isset($keyDetails["ec"]["curve_name"])){
throw new \InvalidArgumentException("Key must be an EC key");
}
$curveName = $keyDetails["ec"]["curve_name"];
if($curveName !== JwtUtils::BEDROCK_SIGNING_KEY_CURVE_NAME){
throw new \InvalidArgumentException("Key must belong to the " . JwtUtils::BEDROCK_SIGNING_KEY_CURVE_NAME . " elliptic curve, got $curveName");
}
}
public static function generateSharedSecret(\OpenSSLAsymmetricKey $localPriv, \OpenSSLAsymmetricKey $remotePub) : \GMP{
self::validateKey($localPriv);
self::validateKey($remotePub);
$hexSecret = openssl_pkey_derive($remotePub, $localPriv, 48);
if($hexSecret === false){
throw new \InvalidArgumentException("Failed to derive shared secret: " . openssl_error_string());
}
return gmp_init(bin2hex($hexSecret), 16);
}
public static function generateKey(\GMP $secret, string $salt) : string{
return Utils::assumeNotFalse(openssl_digest($salt . hex2bin(str_pad(gmp_strval($secret, 16), 96, "0", STR_PAD_LEFT)), 'sha256', true));
}
public static function generateServerHandshakeJwt(\OpenSSLAsymmetricKey $serverPriv, string $salt) : string{
$derPublicKey = JwtUtils::emitDerPublicKey($serverPriv);
return JwtUtils::create(
[
"x5u" => base64_encode($derPublicKey),
"alg" => "ES384"
],
[
"salt" => base64_encode($salt)
],
$serverPriv
);
}
}