FrameReader::getMaxLength() - Code Metrics - Inspection of "WebSockets -- frame overhauling, stable fragmentat..." - hfw/socket - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Branch — master (ec9c11)

by y

created 2020-03-11 12:06 UTC

FrameReader::getMaxLength() A

↳ Parent: FrameReader

Complexity

Conditions	1
Paths	1

Size

Total Lines

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
dl	0
loc	3
rs	10
c	0
b	0
f	0
cc	1
nc	1
nop	0

<?php

namespace Helix\Socket\WebSocket;

use Generator;
use InvalidArgumentException;

/**
 * Reads frames from the peer.
 */
class FrameReader {

    // todo? doesn't allow unmasked frames.
    //                         op((char     )|(short     )|(bigint      ))(mask       )
    protected const REGEXP = '/^.([\x80-\xfd]|\xfe(?<n>..)|\xff(?<J>.{8}))(?<mask>.{4})/s';

    const MAX_LENGTH_RANGE = [125, 2 ** 63 - 1];

    /**
     * @var string
     */
    protected $buffer = '';

    /**
     * @var WebSocketClient
     */
    protected $client;

    /**
     * @var array
     */
    protected $head = [];

    /**
     * Payload size limit.
     *
     * Must fall within {@see MAX_LENGTH_RANGE} (inclusive).
     *
     * Defaults to 10 MiB.
     *
     * https://tools.ietf.org/html/rfc6455#section-5.2
     * > ... interpreted as a 64-bit unsigned integer (the
     * > most significant bit MUST be 0) ...
     *
     * @var int
     */
    protected $maxLength = 10 * 1024 * 1024;

    public function __construct (WebSocketClient $client) {
        $this->client = $client;
    }

    /**
     * @return Frame|null
     */
    protected function getFrame () {
        if (!$this->head) {

            if (preg_match(self::REGEXP, $this->buffer, $head)) {
                [, $op, $len] = unpack('C2', $head[0]);
function someFunction() {
    $x = 5;
    echo $x;
}
                $len = [0xfe => 'n', 0xff => 'J'][$len] ?? ($len & 0x7f);
function someFunction() {
    $x = 5;
    echo $x;
}
                $this->head = [
                    'final' => $op & 0x80,
                    'rsv' => $op & Frame::RSV123,
                    'opCode' => $op & 0x0f,
                    'length' => is_int($len) ? $len : unpack($len, $head[$len])[1],
                    'mask' => array_values(unpack('C*', $head['mask'])),
                ];
                $this->buffer = substr($this->buffer, strlen($head[0]));
                $this->validate();
            }
            elseif (strlen($this->buffer) >= 14) { // max head room
                throw new WebSocketError(Frame::CLOSE_PROTOCOL_ERROR, 'Bad frame.');
            }
            else {
                return null;
            }
        }
        $length = $this->head['length'];
        if (strlen($this->buffer) >= $length) {
            $payload = substr($this->buffer, 0, $length);
            $this->buffer = substr($this->buffer, $length);
            $mask = $this->head['mask'];
            for ($i = 0; $i < $length; $i++) {
                $payload[$i] = chr(ord($payload[$i]) ^ $mask[$i % 4]);
            }
            $frame = new Frame($this->head['final'], $this->head['rsv'], $this->head['opCode'], $payload);
            $this->head = [];
            return $frame;
        }
        return null;
    }

    /**
     * Constructs and yields all available frames from the peer.
     *
     * @return Generator|Frame[]
     */
    public function getFrames () {
        $this->buffer .= $this->client->recvAll();
        while ($frame = $this->getFrame()) {
            yield $frame;
        }
    }

    /**
     * @return int
     */
    public function getMaxLength (): int {
        return $this->maxLength;
    }

    /**
     * @param int $bytes
     * @return $this
     */
    public function setMaxLength (int $bytes) {
        if ($bytes < self::MAX_LENGTH_RANGE[0] or $bytes > self::MAX_LENGTH_RANGE[1]) {
            throw new InvalidArgumentException('Max length must be within range [125,2^63-1]');
        }
        $this->maxLength = $bytes;
        return $this;
    }

    /**
     * Validates the current head by not throwing.
     *
     * @throws WebSocketError
     */
    protected function validate (): void {
        if ($this->head['length'] > $this->maxLength) {
            throw new WebSocketError(Frame::CLOSE_TOO_LARGE, "Payload would exceed {$this->maxLength} bytes");
        }
        $opCode = $this->head['opCode'];
        $name = Frame::NAMES[$opCode];
        if ($opCode & 0x08) { // control
            if ($opCode > Frame::OP_PONG) {
                throw new WebSocketError(Frame::CLOSE_PROTOCOL_ERROR, "Received {$name}");
            }
            if (!$this->head['final']) {
                throw new WebSocketError(Frame::CLOSE_PROTOCOL_ERROR, "Received fragmented {$name}");
            }
        }
        elseif ($opCode > Frame::OP_BINARY) { // data
            throw new WebSocketError(Frame::CLOSE_PROTOCOL_ERROR, "Received {$name}");
        }
    }
}

1			<?php
2
3			namespace Helix\Socket\WebSocket;
4
5			use Generator;
6			use InvalidArgumentException;
7
8			/**
9			* Reads frames from the peer.
10			*/
11			class FrameReader {
12
13			// todo? doesn't allow unmasked frames.
14			// op((char )\|(short )\|(bigint ))(mask )
15			protected const REGEXP = '/^.([\x80-\xfd]\|\xfe(?<n>..)\|\xff(?<J>.{8}))(?<mask>.{4})/s';
16
17			const MAX_LENGTH_RANGE = [125, 2 ** 63 - 1];
18
19			/**
20			* @var string
21			*/
22			protected $buffer = '';
23
24			/**
25			* @var WebSocketClient
26			*/
27			protected $client;
28
29			/**
30			* @var array
31			*/
32			protected $head = [];
33
34			/**
35			* Payload size limit.
36			*
37			* Must fall within {@see MAX_LENGTH_RANGE} (inclusive).
38			*
39			* Defaults to 10 MiB.
40			*
41			* https://tools.ietf.org/html/rfc6455#section-5.2
42			* > ... interpreted as a 64-bit unsigned integer (the
43			* > most significant bit MUST be 0) ...
44			*
45			* @var int
46			*/
47			protected $maxLength = 10 * 1024 * 1024;
48
49			public function __construct (WebSocketClient $client) {
50			$this->client = $client;
51			}
52
53			/**
54			* @return Frame\|null
55			*/
56			protected function getFrame () {
57			if (!$this->head) {
			0 ignored issues – show Bug Best Practice introduced 2020-03-11 12:08 UTC by Report Bug Copy Issue Report The expression `$this->head` of type `array` is implicitly converted to a boolean; are you sure this is intended? If so, consider using `empty($expr)` instead to make it clear that you intend to check for an array without elements. This check marks implicit conversions of arrays to boolean values in a comparison. While in PHP an empty array is considered to be equal (but not identical) to false, this is not always apparent. Consider making the comparison explicit by using `empty(..)` or `! empty(...)` instead. Loading history...
58			if (preg_match(self::REGEXP, $this->buffer, $head)) {
59			[, $op, $len] = unpack('C2', $head[0]);
			0 ignored issues – show Bug introduced 2020-03-11 12:08 UTC by Report Bug Copy Issue Report The variable `$op` does not exist. Did you forget to declare it? This check marks access to variables or properties that have not been declared yet. While PHP has no explicit notion of declaring a variable, accessing it before a value is assigned to it is most likely a bug. Loading history... Bug introduced 2020-03-11 12:08 UTC by Report Bug Copy Issue Report The variable `$len` seems only to be defined at a later point. Did you maybe move this code here without moving the variable definition? This error can happen if you refactor code and forget to move the variable initialization. Let’s take a look at a simple example: function someFunction() { $x = 5; echo $x; } The above code is perfectly fine. Now imagine that we re-order the statements: function someFunction() { echo $x; $x = 5; } In that case, `$x` would be read before it is initialized. This was a very basic example, however the principle is the same for the found issue. Loading history...
60			$len = [0xfe => 'n', 0xff => 'J'][$len] ?? ($len & 0x7f);
			0 ignored issues – show Bug introduced 2020-03-11 12:08 UTC by Report Bug Copy Issue Report The variable `$len` seems only to be defined at a later point. Did you maybe move this code here without moving the variable definition? This error can happen if you refactor code and forget to move the variable initialization. Let’s take a look at a simple example: function someFunction() { $x = 5; echo $x; } The above code is perfectly fine. Now imagine that we re-order the statements: function someFunction() { echo $x; $x = 5; } In that case, `$x` would be read before it is initialized. This was a very basic example, however the principle is the same for the found issue. Loading history...
61			$this->head = [
62			'final' => $op & 0x80,
63			'rsv' => $op & Frame::RSV123,
64			'opCode' => $op & 0x0f,
65			'length' => is_int($len) ? $len : unpack($len, $head[$len])[1],
66			'mask' => array_values(unpack('C*', $head['mask'])),
67			];
68			$this->buffer = substr($this->buffer, strlen($head[0]));
69			$this->validate();
70			}
71			elseif (strlen($this->buffer) >= 14) { // max head room
72			throw new WebSocketError(Frame::CLOSE_PROTOCOL_ERROR, 'Bad frame.');
73			}
74			else {
75			return null;
76			}
77			}
78			$length = $this->head['length'];
79			if (strlen($this->buffer) >= $length) {
80			$payload = substr($this->buffer, 0, $length);
81			$this->buffer = substr($this->buffer, $length);
82			$mask = $this->head['mask'];
83			for ($i = 0; $i < $length; $i++) {
84			$payload[$i] = chr(ord($payload[$i]) ^ $mask[$i % 4]);
85			}
86			$frame = new Frame($this->head['final'], $this->head['rsv'], $this->head['opCode'], $payload);
87			$this->head = [];
88			return $frame;
89			}
90			return null;
91			}
92
93			/**
94			* Constructs and yields all available frames from the peer.
95			*
96			* @return Generator\|Frame[]
97			*/
98			public function getFrames () {
99			$this->buffer .= $this->client->recvAll();
100			while ($frame = $this->getFrame()) {
101			yield $frame;
102			}
103			}
104
105			/**
106			* @return int
107			*/
108			public function getMaxLength (): int {
109			return $this->maxLength;
110			}
111
112			/**
113			* @param int $bytes
114			* @return $this
115			*/
116			public function setMaxLength (int $bytes) {
117			if ($bytes < self::MAX_LENGTH_RANGE[0] or $bytes > self::MAX_LENGTH_RANGE[1]) {
118			throw new InvalidArgumentException('Max length must be within range [125,2^63-1]');
119			}
120			$this->maxLength = $bytes;
121			return $this;
122			}
123
124			/**
125			* Validates the current head by not throwing.
126			*
127			* @throws WebSocketError
128			*/
129			protected function validate (): void {
130			if ($this->head['length'] > $this->maxLength) {
131			throw new WebSocketError(Frame::CLOSE_TOO_LARGE, "Payload would exceed {$this->maxLength} bytes");
132			}
133			$opCode = $this->head['opCode'];
134			$name = Frame::NAMES[$opCode];
135			if ($opCode & 0x08) { // control
136			if ($opCode > Frame::OP_PONG) {
137			throw new WebSocketError(Frame::CLOSE_PROTOCOL_ERROR, "Received {$name}");
138			}
139			if (!$this->head['final']) {
140			throw new WebSocketError(Frame::CLOSE_PROTOCOL_ERROR, "Received fragmented {$name}");
141			}
142			}
143			elseif ($opCode > Frame::OP_BINARY) { // data
144			throw new WebSocketError(Frame::CLOSE_PROTOCOL_ERROR, "Received {$name}");
145			}
146			}
147			}

hfw / socket

Branch — master (ec9c11)

FrameReader::getMaxLength() A

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