Passed
Pull Request — master (#18)
by Marc
03:56
created

Handshake::__construct()   A

Complexity

Conditions 1
Paths 1

Size

Total Lines 7
Code Lines 5

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 6
CRAP Score 1

Importance

Changes 0
Metric Value
dl 0
loc 7
ccs 6
cts 6
cp 1
rs 9.4285
c 0
b 0
f 0
cc 1
eloc 5
nc 1
nop 3
crap 1
1
<?php
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declare(strict_types=1);
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/**
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 * @license http://www.apache.org/licenses/ Apache License 2.0
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 * @license https://github.com/danielmewes/php-rql Apache License 2.0
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 * @Author Daniel Mewes https://github.com/danielmewes
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 * @Author Timon Bolier https://github.com/tbolier
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 *
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 * The Handshake class contains parts of code copied from the original PHP-RQL library under the Apache License 2.0:
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 * @see https://github.com/danielmewes/php-rql/blob/master/rdb/Handshake.php
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 *
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 * Stating the following changes have been done to the parts of the code copied in the Handshake Class:
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 * - Amendments to code styles and control structures.
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 * - Abstraction of code to new methods to improve readability.
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 * - Removed obsolete code.
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 */
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namespace TBolier\RethinkQL\Connection\Socket;
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use Psr\Http\Message\StreamInterface;
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class Handshake implements HandshakeInterface
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{
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    /**
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     * @var string
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     */
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    private $username;
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    /**
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     * @var string
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     */
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    private $password;
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    /**
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     * @var string
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     */
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    private $protocolVersion = 0;
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    /**
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     * @var int
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     */
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    private $state;
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    /**
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     * @var string
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     */
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    private $myR;
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    /**
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     * @var string
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     */
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    private $clientFirstMessage;
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    /**
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     * @var string
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     */
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    private $serverSignature;
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    /**
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     * @var int
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     */
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    private $version;
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    /**
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     * @param string $username
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     * @param string $password
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     * @param int $version
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     */
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    public function __construct(string $username, string $password, int $version)
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    {
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        $this->username = $username;
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        $this->password = $password;
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        $this->state = 0;
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        $this->version = $version;
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    }
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    /**
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     * @inheritdoc
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     * @throws \RuntimeException
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     * @throws Exception
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     */
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    public function hello(StreamInterface $stream): void
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    {
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        try {
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            $handshakeResponse = null;
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            while (true) {
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                if (!$stream->isWritable()) {
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                    throw new Exception('Not connected');
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                }
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                if ($handshakeResponse !== null && preg_match('/^ERROR:\s(.+)$/i', $handshakeResponse,
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                        $errorMatch)) {
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                    throw new Exception($errorMatch[1]);
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                }
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                try {
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                    $msg = $this->nextMessage($handshakeResponse);
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                } catch (Exception $e) {
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                    $stream->close();
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                    throw $e;
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                }
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104 18
                if ($msg === 'successful') {
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                    break;
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                }
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                if ($msg !== '') {
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                    $stream->write($msg);
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                }
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                // Read null-terminated response
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                $handshakeResponse = $stream->getContents();
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            }
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        } catch (Exception $e) {
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            $stream->close();
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            throw $e;
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        }
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    }
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    /**
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     * @param $response
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     * @return string
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     * @throws Exception
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     */
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    private function nextMessage(string $response = null): ?string
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    {
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        switch ($this->state) {
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            case 0:
0 ignored issues
show
Coding Style introduced by
case statements should be defined using a colon.

As per the PSR-2 coding standard, case statements should not be wrapped in curly braces. There is no need for braces, since each case is terminated by the next break.

There is also the option to use a semicolon instead of a colon, this is discouraged because many programmers do not even know it works and the colon is universal between programming languages.

switch ($expr) {
    case "A": { //wrong
        doSomething();
        break;
    }
    case "B"; //wrong
        doSomething();
        break;
    case "C": //right
        doSomething();
        break;
}

To learn more about the PSR-2 coding standard, please refer to the PHP-Fig.

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131 18
                return $this->createHandshakeMessage($response);
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            case 1:
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                return $this->verifyProtocol($response);
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            case 2:
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                return $this->createAuthenticationMessage($response);
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            case 3:
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                return $this->verifyAuthentication($response);
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            default:
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                throw new Exception('Illegal handshake state');
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        }
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    }
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    /**
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     * @param string $password
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     * @param string $salt
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     * @param int $iterations
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     * @return string
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     */
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    private function pkbdf2Hmac(string $password, string $salt, int $iterations): string
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    {
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        $t = hash_hmac('sha256', $salt . "\x00\x00\x00\x01", $password, true);
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        $u = $t;
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        for ($i = 0; $i < $iterations - 1; ++$i) {
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            $t = hash_hmac('sha256', $t, $password, true);
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            $u ^= $t;
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        }
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        return $u;
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    }
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    /**
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     * @param $response
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     * @return string
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     */
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    private function createHandshakeMessage($response): string
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    {
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        $response === null or die('Illegal handshake state');
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        $this->myR = base64_encode(openssl_random_pseudo_bytes(18));
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        $this->clientFirstMessage = 'n=' . $this->username . ',r=' . $this->myR;
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        $binaryVersion = pack('V', $this->version);
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        $this->state = 1;
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        return
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            $binaryVersion
178 18
            . json_encode(
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                [
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                    'protocol_version' => $this->protocolVersion,
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                    'authentication_method' => 'SCRAM-SHA-256',
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                    'authentication' => 'n,,' . $this->clientFirstMessage,
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                ]
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            )
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            . \chr(0);
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    }
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    /**
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     * @param $response
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     * @return string
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     * @throws Exception
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     */
193 16
    private function verifyProtocol($response): string
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    {
195 16
        if (strpos($response, 'ERROR') === 0) {
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            throw new Exception(
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                'Received an unexpected reply. You may be attempting to connect to '
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                . 'a RethinkDB server that is too old for this driver. The minimum '
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                . 'supported server version is 2.3.0.'
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            );
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        }
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        $json = json_decode($response, true);
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        if ($json['success'] === false) {
205 1
            throw new Exception('Handshake failed: ' . $json["error"]);
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        }
207 15
        if ($this->protocolVersion > $json['max_protocol_version']
208 15
            || $this->protocolVersion < $json['min_protocol_version']) {
209 1
            throw new Exception('Unsupported protocol version.');
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        }
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        $this->state = 2;
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214 14
        return '';
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    }
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    /**
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     * @param $response
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     * @return string
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     * @throws Exception
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     */
222 14
    private function createAuthenticationMessage($response): string
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    {
224 14
        $json = json_decode($response, true);
225 14
        if ($json['success'] === false) {
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            throw new Exception('Handshake failed: ' . $json['error']);
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        }
228 14
        $serverFirstMessage = $json['authentication'];
229 14
        $authentication = [];
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        foreach (explode(',', $json['authentication']) as $var) {
231 14
            $pair = explode('=', $var);
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            $authentication[$pair[0]] = $pair[1];
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        }
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        $serverR = $authentication['r'];
235 14
        if (strpos($serverR, $this->myR) !== 0) {
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            throw new Exception('Invalid nonce from server.');
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        }
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        $salt = base64_decode($authentication['s']);
239 14
        $iterations = (int)$authentication['i'];
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        $clientFinalMessageWithoutProof = 'c=biws,r=' . $serverR;
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        $saltedPassword = $this->pkbdf2Hmac($this->password, $salt, $iterations);
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        $clientKey = hash_hmac('sha256', 'Client Key', $saltedPassword, true);
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        $storedKey = hash('sha256', $clientKey, true);
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        $authMessage =
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            $this->clientFirstMessage . ',' . $serverFirstMessage . ',' . $clientFinalMessageWithoutProof;
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        $clientSignature = hash_hmac('sha256', $authMessage, $storedKey, true);
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        $clientProof = $clientKey ^ $clientSignature;
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        $serverKey = hash_hmac('sha256', 'Server Key', $saltedPassword, true);
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        $this->serverSignature = hash_hmac('sha256', $authMessage, $serverKey, true);
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        $this->state = 3;
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        return
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            json_encode(
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                [
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                    'authentication' => $clientFinalMessageWithoutProof . ',p=' . base64_encode($clientProof),
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                ]
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            )
265 14
            . \chr(0);
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    }
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    /**
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     * @param $response
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     * @return string
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     * @throws Exception
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     */
273 14
    private function verifyAuthentication($response): string
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    {
275 14
        $json = json_decode($response, true);
276 14
        if ($json['success'] === false) {
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            throw new Exception('Handshake failed: ' . $json['error']);
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        }
279 14
        $authentication = [];
280 14
        foreach (explode(',', $json['authentication']) as $var) {
281 14
            $pair = explode('=', $var);
282 14
            $authentication[$pair[0]] = $pair[1];
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        }
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285 14
        $this->checkSignature(base64_decode($authentication['v']));
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        $this->state = 4;
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289 14
        return 'successful';
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    }
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    /**
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     * @param $signature
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     */
295 14
    private function checkSignature($signature)
296
    {
297 14
        if (!hash_equals($signature, $this->serverSignature)) {
298
            throw new Exception('Invalid server signature.');
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        }
300 14
    }
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}
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