Completed
Branch webservice-support (1bfa77)
by John
02:37
created

Security::decodeMerchantParameters()   A

Complexity

Conditions 1
Paths 1

Size

Total Lines 4
Code Lines 2

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 2
CRAP Score 1

Importance

Changes 0
Metric Value
dl 0
loc 4
ccs 2
cts 2
cp 1
rs 10
c 0
b 0
f 0
cc 1
eloc 2
nc 1
nop 1
crap 1
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<?php
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namespace Omnipay\Redsys\Message;
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use Omnipay\Common\Exception\RuntimeException;
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/**
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 * Security
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 *
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 * This class provides common encoding, decoding and signing functions.
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 * While all of this code could be called statically, it is left as a
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 * regular class in order to faciliate unit testing. If alternate
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 * encryption methods are provided later, the VERSION const can be
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 * switched to a constructor option (and validated against a whitelist).
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 */
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class Security
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{
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    /** @var string */
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    const VERSION = 'HMAC_SHA256_V1';
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    /**
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     * Encode merchant parameters
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     *
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     * @param array $data  The parameters to encode
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     *
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     * @return string Encoded data
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     */
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    public function encodeMerchantParameters($data)
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    {
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        return base64_encode(json_encode($data));
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    }
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    /**
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     * Decode merchant parameters
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     *
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     * @param string $data  The encoded string of parameters
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     *
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     * @return array Decoded data
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     */
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    public function decodeMerchantParameters($data)
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    {
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        return (array)json_decode(base64_decode(strtr($data, '-_', '+/')));
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    }
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    /**
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     * Encrypt message with given key and default IV
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     *
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     * @param string $message  The message to encrypt
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     * @param string $key      The key used to encrypt the message
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     *
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     * @return string Encrypted message
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     *
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     * @throws RuntimeException
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     */
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    protected function encryptMessage($message, $key)
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    {
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        $iv = implode(array_map('chr', array(0, 0, 0, 0, 0, 0, 0, 0)));
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        if ($this->hasValidEncryptionMethod()) {
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            $ciphertext = mcrypt_encrypt(MCRYPT_3DES, $key, $message, MCRYPT_MODE_CBC, $iv);
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        } else {
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            throw new RuntimeException('No valid encryption extension installed');
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        }
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        return $ciphertext;
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    }
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    /**
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     * Check if the system has a valid encryption method available
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     *
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     * @todo add or switch to extension_loaded()?
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     *
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     * @return bool
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     */
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    public function hasValidEncryptionMethod()
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    {
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        return function_exists('mcrypt_encrypt');
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    }
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    /**
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     * Create signature hash used to verify messages
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     *
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     * @todo Add if-check on algorithm to match against signature version as new param?
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     *
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     * @param string $message  The message to encrypt
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     * @param string $salt     Unique salt used to generate the ciphertext
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     * @param string $key      The key used to encrypt the message
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     *
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     * @return string Generated signature
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     */
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    public function createSignature($message, $salt, $key)
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    {
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        $ciphertext = $this->encryptMessage($salt, $key);
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        return base64_encode(hash_hmac('sha256', $message, $ciphertext, true));
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    }
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    public function createReturnSignature($message, $salt, $key)
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    {
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        return strtr($this->createSignature($message, $salt, $key), '+/', '-_');
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    }
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}
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