Passed
Push — master ( 9c982a...ad2785 )
by Tony Karavasilev (Тони
19:53
created

TripleDes::fetchAlgorithmMethodName()   A

Complexity

Conditions 2
Paths 2

Size

Total Lines 3
Code Lines 1

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 2
CRAP Score 2

Importance

Changes 1
Bugs 0 Features 0
Metric Value
eloc 1
c 1
b 0
f 0
dl 0
loc 3
ccs 2
cts 2
cp 1
rs 10
cc 2
nc 2
nop 0
crap 2
1
<?php
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/**
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 * The 3DES-168 (T-DES) encryption algorithm class.
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 */
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namespace CryptoManana\SymmetricEncryption;
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use \CryptoManana\Core\Abstractions\MessageEncryption\AbstractBlockCipherAlgorithm as SymmetricBlockCipherAlgorithm;
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/**
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 * Class TripleDes - The 3DES-168 (T-DES) encryption algorithm object.
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 *
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 * @package CryptoManana\SymmetricEncryption
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 */
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class TripleDes extends SymmetricBlockCipherAlgorithm
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{
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    /**
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     * The internal name of the algorithm.
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     */
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    const ALGORITHM_NAME = 'DES-EDE3';
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    /**
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     * The internal secret key size measured in raw bytes length for the algorithm
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     *
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     * @internal For the current algorithm: 192 bits (24 bytes), but 168 bits (21 bytes) are usable
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     */
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    const KEY_SIZE = 24;
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    /**
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     * The internal initialization vector (IV) size measured in raw bytes length for the algorithm
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     *
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     * @internal For the current algorithm: 64 bits (8 bytes)
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     */
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    const IV_SIZE = 8;
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    /**
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     * The internal operational block size measured in raw bytes length for the algorithm
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     *
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     * @internal For the current algorithm: 64 bits (8 bytes)
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     */
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    const BLOCK_SIZE = 8;
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    /**
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     * List of valid block operation modes.
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     *
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     * @var array Block mode codes.
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     */
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    protected static $validBlockModes = [
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        self::CBC_MODE,
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        self::CFB_MODE,
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        self::OFB_MODE,
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        self::ECB_MODE
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    ];
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    /**
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     * Fetch the correctly formatted internal encryption algorithm method name.
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     *
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     * @return string The symmetric encryption algorithm standard.
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     */
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    protected function fetchAlgorithmMethodName()
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    {
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        return ($this->mode === self::ECB_MODE) ? static::ALGORITHM_NAME : static::ALGORITHM_NAME . '-' . $this->mode;
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    }
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    /**
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     * Internal method for the validation of the system support of the given block operation mode.
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     *
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     * @param string $mode The block mode name.
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     *
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     * @throws \Exception Validation errors.
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     *
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     * @codeCoverageIgnore
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     */
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    protected function validateBlockModeSupport($mode)
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    {
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        $mode = strtoupper($mode);
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        $methodName = ($mode === self::ECB_MODE) ? static::ALGORITHM_NAME : static::ALGORITHM_NAME . '-' . $mode;
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        if (!in_array($methodName, openssl_get_cipher_methods(), true)) {
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            throw new \RuntimeException(
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                'The algorithm `' . $methodName . '`is not supported under the current system configuration.'
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            );
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        }
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    }
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}
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