Failed Conditions
Push — master ( d40a11...28d61e )
by Florent
07:16
created

RSACrypt   A

Complexity

Total Complexity 35

Size/Duplication

Total Lines 311
Duplicated Lines 0 %

Coupling/Cohesion

Components 1
Dependencies 3

Importance

Changes 0
Metric Value
wmc 35
lcom 1
cbo 3
dl 0
loc 311
rs 9
c 0
b 0
f 0

13 Methods

Rating   Name   Duplication   Size   Complexity  
A encrypt() 0 11 3
A decrypt() 0 11 3
B encryptWithRSA15() 0 24 3
B decryptWithRSA15() 0 23 5
A encryptWithRSAOAEP() 0 16 3
A decryptWithRSAOAEP() 0 16 3
A convertIntegerToOctetString() 0 9 2
A convertOctetStringToInteger() 0 4 1
A getRSAEP() 0 8 3
A getRSADP() 0 8 3
A getMGF1() 0 11 2
A encryptRSAESOAEP() 0 19 1
B getRSAESOAEP() 0 24 3
1
<?php
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3
declare(strict_types=1);
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5
/*
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 * The MIT License (MIT)
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 *
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 * Copyright (c) 2014-2018 Spomky-Labs
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 *
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 * This software may be modified and distributed under the terms
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 * of the MIT license.  See the LICENSE file for details.
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 */
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namespace Jose\Component\Encryption\Util;
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use Jose\Component\Core\Util\BigInteger;
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use Jose\Component\Core\Util\Hash;
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use Jose\Component\Core\Util\RSAKey;
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/**
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 * @internal
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 */
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class RSACrypt
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{
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    /**
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     * Optimal Asymmetric Encryption Padding (OAEP).
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     */
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    public const ENCRYPTION_OAEP = 1;
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    /**
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     * Use PKCS#1 padding.
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     */
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    public const ENCRYPTION_PKCS1 = 2;
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    /**
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     * @param RSAKey      $key
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     * @param string      $data
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     * @param int         $mode
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     * @param null|string $hash
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     *
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     * @return string
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     */
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    public static function encrypt(RSAKey $key, string $data, int $mode, ?string $hash = null): string
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    {
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        switch ($mode) {
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            case self::ENCRYPTION_OAEP:
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                return self::encryptWithRSAOAEP($key, $data, $hash);
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            case self::ENCRYPTION_PKCS1:
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                return self::encryptWithRSA15($key, $data);
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            default:
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                throw new \InvalidArgumentException('Unsupported mode.');
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        }
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    }
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    /**
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     * @param RSAKey      $key
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     * @param string      $plaintext
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     * @param int         $mode
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     * @param null|string $hash
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     *
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     * @return string
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     */
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    public static function decrypt(RSAKey $key, string $plaintext, int $mode, ?string $hash = null): string
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    {
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        switch ($mode) {
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            case self::ENCRYPTION_OAEP:
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                return self::decryptWithRSAOAEP($key, $plaintext, $hash);
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            case self::ENCRYPTION_PKCS1:
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                return self::decryptWithRSA15($key, $plaintext);
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            default:
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                throw new \InvalidArgumentException('Unsupported mode.');
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        }
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    }
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    /**
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     * @param RSAKey $key
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     * @param string $data
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     *
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     * @return string
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     */
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    public static function encryptWithRSA15(RSAKey $key, string $data): string
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    {
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        $mLen = mb_strlen($data, '8bit');
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        if ($mLen > $key->getModulusLength() - 11) {
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            throw new \InvalidArgumentException('Message too long');
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        }
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        $psLen = $key->getModulusLength() - $mLen - 3;
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        $ps = '';
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        while (mb_strlen($ps, '8bit') !== $psLen) {
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            $temp = random_bytes($psLen - mb_strlen($ps, '8bit'));
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            $temp = str_replace("\x00", '', $temp);
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            $ps .= $temp;
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        }
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        $type = 2;
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        $data = chr(0).chr($type).$ps.chr(0).$data;
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        $data = BigInteger::createFromBinaryString($data);
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        $c = self::getRSAEP($key, $data);
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        $c = self::convertIntegerToOctetString($c, $key->getModulusLength());
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        return $c;
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    }
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    /**
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     * @param RSAKey $key
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     * @param string $c
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     *
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     * @return string
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     */
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    public static function decryptWithRSA15(RSAKey $key, string $c): string
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    {
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        if (mb_strlen($c, '8bit') !== $key->getModulusLength()) {
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            throw new \InvalidArgumentException('Unable to decrypt');
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        }
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        $c = BigInteger::createFromBinaryString($c);
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        $m = self::getRSADP($key, $c);
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        $em = self::convertIntegerToOctetString($m, $key->getModulusLength());
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        if (0 != ord($em[0]) || ord($em[1]) > 2) {
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            throw new \InvalidArgumentException('Unable to decrypt');
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        }
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        $ps = mb_substr($em, 2, mb_strpos($em, chr(0), 2, '8bit') - 2, '8bit');
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        $m = mb_substr($em, mb_strlen($ps, '8bit') + 3, null, '8bit');
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        if (mb_strlen($ps, '8bit') < 8) {
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            throw new \InvalidArgumentException('Unable to decrypt');
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        }
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        return $m;
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    }
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    /**
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     * Encryption.
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     *
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     * @param RSAKey $key
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     * @param string $plaintext
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     * @param string $hash_algorithm
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     *
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     * @return string
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     */
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    public static function encryptWithRSAOAEP(RSAKey $key, string $plaintext, string $hash_algorithm): string
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    {
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        /** @var Hash $hash */
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        $hash = Hash::$hash_algorithm();
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        $length = $key->getModulusLength() - 2 * $hash->getLength() - 2;
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        if (0 >= $length) {
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            throw new \RuntimeException();
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        }
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        $plaintext = str_split($plaintext, $length);
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        $ciphertext = '';
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        foreach ($plaintext as $m) {
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            $ciphertext .= self::encryptRSAESOAEP($key, $m, $hash);
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        }
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        return $ciphertext;
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    }
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    /**
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     * Decryption.
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     *
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     * @param RSAKey $key
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     * @param string $ciphertext
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     * @param string $hash_algorithm
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     *
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     * @return string
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     */
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    public static function decryptWithRSAOAEP(RSAKey $key, string $ciphertext, string $hash_algorithm): string
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    {
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        if (0 >= $key->getModulusLength()) {
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            throw new \RuntimeException();
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        }
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        $hash = Hash::$hash_algorithm();
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        $ciphertext = str_split($ciphertext, $key->getModulusLength());
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        $ciphertext[count($ciphertext) - 1] = str_pad($ciphertext[count($ciphertext) - 1], $key->getModulusLength(), chr(0), STR_PAD_LEFT);
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        $plaintext = '';
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        foreach ($ciphertext as $c) {
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            $temp = self::getRSAESOAEP($key, $c, $hash);
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            $plaintext .= $temp;
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        }
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        return $plaintext;
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    }
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    /**
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     * @param BigInteger $x
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     * @param int        $xLen
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     *
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     * @return string
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     */
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    private static function convertIntegerToOctetString(BigInteger $x, int $xLen): string
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    {
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        $x = $x->toBytes();
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        if (mb_strlen($x, '8bit') > $xLen) {
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            throw new \RuntimeException('Invalid length.');
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        }
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        return str_pad($x, $xLen, chr(0), STR_PAD_LEFT);
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    }
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    /**
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     * Octet-String-to-Integer primitive.
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     *
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     * @param string $x
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     *
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     * @return BigInteger
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     */
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    private static function convertOctetStringToInteger(string $x): BigInteger
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    {
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        return BigInteger::createFromBinaryString($x);
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    }
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    /**
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     * RSA EP.
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     *
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     * @param RSAKey     $key
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     * @param BigInteger $m
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     *
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     * @return BigInteger
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     */
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    private static function getRSAEP(RSAKey $key, BigInteger $m): BigInteger
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    {
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        if ($m->compare(BigInteger::createFromDecimal(0)) < 0 || $m->compare($key->getModulus()) > 0) {
0 ignored issues
show
Documentation introduced by Spomky
$key->getModulus() is of type object<Jose\Component\Core\Util\BigInteger>, but the function expects a object<self>.

It seems like the type of the argument is not accepted by the function/method which you are calling.

In some cases, in particular if PHP’s automatic type-juggling kicks in this might be fine. In other cases, however this might be a bug.

We suggest to add an explicit type cast like in the following example:

function acceptsInteger($int) { }

$x = '123'; // string "123"

// Instead of
acceptsInteger($x);

// we recommend to use
acceptsInteger((integer) $x);
Loading history...
227
            throw new \RuntimeException();
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        }
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        return RSAKey::exponentiate($key, $m);
0 ignored issues
show
Documentation introduced by Spomky
$key is of type object<Jose\Component\Core\Util\RSAKey>, but the function expects a object<self>.

It seems like the type of the argument is not accepted by the function/method which you are calling.

In some cases, in particular if PHP’s automatic type-juggling kicks in this might be fine. In other cases, however this might be a bug.

We suggest to add an explicit type cast like in the following example:

function acceptsInteger($int) { }

$x = '123'; // string "123"

// Instead of
acceptsInteger($x);

// we recommend to use
acceptsInteger((integer) $x);
Loading history...
231
    }
232
233
    /**
234
     * RSA DP.
235
     *
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     * @param RSAKey     $key
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     * @param BigInteger $c
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     *
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     * @return BigInteger
240
     */
241
    private static function getRSADP(RSAKey $key, BigInteger $c): BigInteger
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    {
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        if ($c->compare(BigInteger::createFromDecimal(0)) < 0 || $c->compare($key->getModulus()) > 0) {
0 ignored issues
show
Documentation introduced by Spomky
$key->getModulus() is of type object<Jose\Component\Core\Util\BigInteger>, but the function expects a object<self>.

It seems like the type of the argument is not accepted by the function/method which you are calling.

In some cases, in particular if PHP’s automatic type-juggling kicks in this might be fine. In other cases, however this might be a bug.

We suggest to add an explicit type cast like in the following example:

function acceptsInteger($int) { }

$x = '123'; // string "123"

// Instead of
acceptsInteger($x);

// we recommend to use
acceptsInteger((integer) $x);
Loading history...
244
            throw new \RuntimeException();
245
        }
246
247
        return RSAKey::exponentiate($key, $c);
0 ignored issues
show
Documentation introduced by Spomky
$key is of type object<Jose\Component\Core\Util\RSAKey>, but the function expects a object<self>.

It seems like the type of the argument is not accepted by the function/method which you are calling.

In some cases, in particular if PHP’s automatic type-juggling kicks in this might be fine. In other cases, however this might be a bug.

We suggest to add an explicit type cast like in the following example:

function acceptsInteger($int) { }

$x = '123'; // string "123"

// Instead of
acceptsInteger($x);

// we recommend to use
acceptsInteger((integer) $x);
Loading history...
248
    }
249
250
    /**
251
     * MGF1.
252
     *
253
     * @param string $mgfSeed
254
     * @param int    $maskLen
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     * @param Hash   $mgfHash
256
     *
257
     * @return string
258
     */
259
    private static function getMGF1(string $mgfSeed, int $maskLen, Hash $mgfHash): string
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    {
261
        $t = '';
262
        $count = ceil($maskLen / $mgfHash->getLength());
263
        for ($i = 0; $i < $count; $i++) {
264
            $c = pack('N', $i);
265
            $t .= $mgfHash->hash($mgfSeed.$c);
266
        }
267
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        return mb_substr($t, 0, $maskLen, '8bit');
269
    }
270
271
    /**
272
     * RSAES-OAEP-ENCRYPT.
273
     *
274
     * @param RSAKey $key
275
     * @param string $m
276
     * @param Hash   $hash
277
     *
278
     * @return string
279
     */
280
    private static function encryptRSAESOAEP(RSAKey $key, string $m, Hash $hash): string
281
    {
282
        $mLen = mb_strlen($m, '8bit');
283
        $lHash = $hash->hash('');
284
        $ps = str_repeat(chr(0), $key->getModulusLength() - $mLen - 2 * $hash->getLength() - 2);
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        $db = $lHash.$ps.chr(1).$m;
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        $seed = random_bytes($hash->getLength());
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        $dbMask = self::getMGF1($seed, $key->getModulusLength() - $hash->getLength() - 1, $hash/*MGF*/);
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        $maskedDB = strval($db ^ $dbMask);
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        $seedMask = self::getMGF1($maskedDB, $hash->getLength(), $hash/*MGF*/);
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        $maskedSeed = $seed ^ $seedMask;
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        $em = chr(0).$maskedSeed.$maskedDB;
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        $m = self::convertOctetStringToInteger($em);
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        $c = self::getRSAEP($key, $m);
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        $c = self::convertIntegerToOctetString($c, $key->getModulusLength());
296
297
        return $c;
298
    }
299
300
    /**
301
     * RSAES-OAEP-DECRYPT.
302
     *
303
     * @param RSAKey $key
304
     * @param string $c
305
     * @param Hash   $hash
306
     *
307
     * @return string
308
     */
309
    private static function getRSAESOAEP(RSAKey $key, string $c, Hash $hash): string
310
    {
311
        $c = self::convertOctetStringToInteger($c);
312
        $m = self::getRSADP($key, $c);
313
        $em = self::convertIntegerToOctetString($m, $key->getModulusLength());
314
        $lHash = $hash->hash('');
315
        $maskedSeed = mb_substr($em, 1, $hash->getLength(), '8bit');
316
        $maskedDB = mb_substr($em, $hash->getLength() + 1, null, '8bit');
317
        $seedMask = self::getMGF1($maskedDB, $hash->getLength(), $hash/*MGF*/);
318
        $seed = strval($maskedSeed ^ $seedMask);
319
        $dbMask = self::getMGF1($seed, $key->getModulusLength() - $hash->getLength() - 1, $hash/*MGF*/);
320
        $db = $maskedDB ^ $dbMask;
321
        $lHash2 = mb_substr($db, 0, $hash->getLength(), '8bit');
322
        $m = mb_substr($db, $hash->getLength(), null, '8bit');
323
        if (!hash_equals($lHash, $lHash2)) {
324
            throw new \RuntimeException();
325
        }
326
        $m = ltrim($m, chr(0));
327
        if (1 !== ord($m[0])) {
328
            throw new \RuntimeException();
329
        }
330
331
        return mb_substr($m, 1, null, '8bit');
332
    }
333
}
334