<?php
declare(strict_types=1);
/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2021 Spomky-Labs
*
* This software may be modified and distributed under the terms
* of the MIT license. See the LICENSE file for details.
*/
namespace Cose\Key;
use function array_key_exists;
use Assert\Assertion;
use Brick\Math\BigInteger;
use FG\ASN1\Universal\BitString;
use FG\ASN1\Universal\Integer;
use FG\ASN1\Universal\NullObject;
use FG\ASN1\Universal\ObjectIdentifier;
use FG\ASN1\Universal\Sequence;
use InvalidArgumentException;
class RsaKey extends Key
{
public const DATA_N = -1;
public const DATA_E = -2;
public const DATA_D = -3;
public const DATA_P = -4;
public const DATA_Q = -5;
public const DATA_DP = -6;
public const DATA_DQ = -7;
public const DATA_QI = -8;
public const DATA_OTHER = -9;
public const DATA_RI = -10;
public const DATA_DI = -11;
public const DATA_TI = -12;
public function __construct(array $data)
{
parent::__construct($data);
Assertion::eq($data[self::TYPE], self::TYPE_RSA, 'Invalid RSA key. The key type does not correspond to a RSA key');
Assertion::keyExists($data, self::DATA_N, 'Invalid RSA key. The modulus is missing');
Assertion::keyExists($data, self::DATA_E, 'Invalid RSA key. The exponent is missing');
}
public function n(): string
{
return $this->get(self::DATA_N);
}
public function e(): string
{
return $this->get(self::DATA_E);
}
public function d(): string
{
Assertion::true($this->isPrivate(), 'The key is not private.');
return $this->get(self::DATA_D);
}
public function p(): string
{
Assertion::true($this->isPrivate(), 'The key is not private.');
return $this->get(self::DATA_P);
}
public function q(): string
{
Assertion::true($this->isPrivate(), 'The key is not private.');
return $this->get(self::DATA_Q);
}
public function dP(): string
{
Assertion::true($this->isPrivate(), 'The key is not private.');
return $this->get(self::DATA_DP);
}
public function dQ(): string
{
Assertion::true($this->isPrivate(), 'The key is not private.');
return $this->get(self::DATA_DQ);
}
public function QInv(): string
{
Assertion::true($this->isPrivate(), 'The key is not private.');
return $this->get(self::DATA_QI);
}
public function other(): array
{
Assertion::true($this->isPrivate(), 'The key is not private.');
return $this->get(self::DATA_OTHER);
}
public function rI(): string
{
Assertion::true($this->isPrivate(), 'The key is not private.');
return $this->get(self::DATA_RI);
}
public function dI(): string
{
Assertion::true($this->isPrivate(), 'The key is not private.');
return $this->get(self::DATA_DI);
}
public function tI(): string
{
Assertion::true($this->isPrivate(), 'The key is not private.');
return $this->get(self::DATA_TI);
}
public function hasPrimes(): bool
{
return $this->has(self::DATA_P) && $this->has(self::DATA_Q);
}
public function primes(): array
{
return [
$this->p(),
$this->q(),
];
}
public function hasExponents(): bool
{
return $this->has(self::DATA_DP) && $this->has(self::DATA_DQ);
}
public function exponents(): array
{
return [
$this->dP(),
$this->dQ(),
];
}
public function hasCoefficient(): bool
{
return $this->has(self::DATA_QI);
}
public function isPublic(): bool
{
return !$this->isPrivate();
}
public function isPrivate(): bool
{
return array_key_exists(self::DATA_D, $this->getData());
}
public function asPem(): string
{
Assertion::false($this->isPrivate(), 'Unsupported for private keys.');
$bitSring = new Sequence(
new Integer($this->fromBase64ToInteger($this->n())),
new Integer($this->fromBase64ToInteger($this->e()))
);
$der = new Sequence(
new Sequence(
new ObjectIdentifier('1.2.840.113549.1.1.1'),
new NullObject()
),
new BitString(bin2hex($bitSring->getBinary()))
);
return $this->pem('PUBLIC KEY', $der->getBinary());
}
private function fromBase64ToInteger(string $value): string
{
$data = unpack('H*', $value);
if (false === $data) {
throw new InvalidArgumentException('Unable to convert to an integer');
}
$hex = current($data);
return BigInteger::fromBase($hex, 16)->toBase(10);
}
private function pem(string $type, string $der): string
{
return sprintf("-----BEGIN %s-----\n", mb_strtoupper($type)).
chunk_split(base64_encode($der), 64, "\n").
sprintf("-----END %s-----\n", mb_strtoupper($type));
}
}