ProxyServer::checkRequest() - Code Metrics - Inspection of "Fix syntax error of proxy.php" - SimpleMachines/SMF2.1 - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Pull Request — release-2.1 (#5917)

by Mathias

created 2020-01-06 10:02 UTC

ProxyServer::checkRequest() B

↳ Parent: ProxyServer

Complexity

Conditions	9
Paths	10

Size

Total Lines	31
Code Lines	16

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
cc	9
eloc	16
c	0
b	0
f	0
nop	0
dl	0
loc	31
rs	8.0555
nc	10

<?php

/**
 * This is a lightweight proxy for serving images, generally meant to be used alongside SSL
 *
 * Simple Machines Forum (SMF)
 *
 * @package SMF
 * @author Simple Machines https://www.simplemachines.org
 * @copyright 2020 Simple Machines and individual contributors
 * @license https://www.simplemachines.org/about/smf/license.php BSD
 *
 * @version 2.1 RC2
 */

if (!defined('SMF'))
	define('SMF', 'PROXY');

if (!defined('SMF_VERSION'))
	define('SMF_VERSION', '2.1 RC2');

if (!defined('SMF_FULL_VERSION'))
	define('SMF_FULL_VERSION', 'SMF ' . SMF_VERSION);

if (!defined('SMF_SOFTWARE_YEAR'))
	define('SMF_SOFTWARE_YEAR', '2020');

if (!defined('JQUERY_VERSION'))
	define('JQUERY_VERSION', '3.4.1');

if (!defined('POSTGRE_TITLE'))
	define('POSTGRE_TITLE', 'PostgreSQL');

if (!defined('MYSQL_TITLE'))
	define('MYSQL_TITLE', 'MySQL');

if (!defined('SMF_USER_AGENT'))
	define('SMF_USER_AGENT', 'Mozilla/5.0 (' . php_uname('s') . ' ' . php_uname('m') . ') AppleWebKit/605.1.15 (KHTML, like Gecko)  SMF/' . strtr(SMF_VERSION, ' ', '.'));

/**
 * Class ProxyServer
 */
class ProxyServer
{
	/** @var bool $enabled Whether or not this is enabled */
	protected $enabled;

	/** @var int $maxSize The maximum size for files to cache */
	protected $maxSize;

	/** @var string $secret A secret code used for hashing */
	protected $secret;

	/** @var string The cache directory */
	protected $cache;

	/** @var int $maxDays until entries get deleted */
	protected $maxDays;

	/** @var int $cachedtime time object cached */
	protected $cachedtime;

	/** @var string $cachedtype type of object cached */
	protected $cachedtype;

	/** @var int $cachedsize size of object cached */
	protected $cachedsize;

	/** @var string $cachedbody body of object cached */
	protected $cachedbody;

	/**
	 * Constructor, loads up the Settings for the proxy
	 *
	 * @access public
	 */
	public function __construct()
	{
		global $image_proxy_enabled, $image_proxy_maxsize, $image_proxy_secret, $cachedir, $sourcedir;

		require_once(dirname(__FILE__) . '/Settings.php');
		require_once($sourcedir . '/Subs.php');

		// Turn off all error reporting; any extra junk makes for an invalid image.
		error_reporting(0);

		$this->enabled = (bool) $image_proxy_enabled;
		$this->maxSize = (int) $image_proxy_maxsize;
		$this->secret = (string) $image_proxy_secret;
		$this->cache = $cachedir . '/images';
		$this->maxDays = 5;
	}

	/**
	 * Checks whether the request is valid or not
	 *
	 * @access public
	 * @return bool Whether the request is valid
	 */
	public function checkRequest()
	{
		if (!$this->enabled)
			return false;

		// Try to create the image cache directory if it doesn't exist
		if (!file_exists($this->cache))
			if (!mkdir($this->cache) || !copy(dirname($this->cache) . '/index.php', $this->cache . '/index.php'))
				return false;

		// Basic sanity check
		$_GET['request'] = validate_iri($_GET['request']);

		// We aren't going anywhere without these
		if (empty($_GET['hash']) || empty($_GET['request']))
			return false;

		$hash = $_GET['hash'];
		$request = $_GET['request'];

		if (hash_hmac('sha1', $request, $this->secret) != $hash)
			return false;

		// Ensure any non-ASCII characters in the URL are encoded correctly
		$request = iri_to_url($request);

		// Attempt to cache the request if it doesn't exist
		if (!$this->isCached($request))
			return $this->cacheImage($request);

		return false;
	}

	/**
	 * Serves the request
	 *
	 * @access public
	 */
	public function serve()
	{
		$request = $_GET['request'];
		// Did we get an error when trying to fetch the image
		$response = $this->checkRequest();
		if (!$response)
		{
			// Throw a 404
			send_http_status(404);
			exit;

		}

		// We should have a cached image at this point
		$cached_file = $this->getCachedPath($request);

		// Read from cache if you need to...
		if ($this->cachedbody === null)
		{
			$cached = json_decode(file_get_contents($cached_file), true);
			$this->cachedtime = $cached['time'];
			$this->cachedtype = $cached['content_type'];
			$this->cachedsize = $cached['size'];
			$this->cachedbody = $cached['body'];
		}

		$time = time();

		// Is the cache expired? Delete and reload.
		if ($time - $this->cachedtime > ($this->maxDays * 86400))
		{
			@unlink($cached_file);
			if ($this->checkRequest())
				$this->serve();
			$this->redirectexit($request);
		}

		$eTag = '"' . substr(sha1($request) . $this->cachedtime, 0, 64) . '"';
		if (!empty($_SERVER['HTTP_IF_NONE_MATCH']) && strpos($_SERVER['HTTP_IF_NONE_MATCH'], $eTag) !== false)
		{
			send_http_status(304);
			exit;

		}

		// Make sure we're serving an image
		$contentParts = explode('/', !empty($this->cachedtype) ? $this->cachedtype : '');
		if ($contentParts[0] != 'image')
			exit;


		$max_age = $time - $this->cachedtime + (5 * 86400);
		header('content-type: ' . $this->cachedtype);
		header('content-length: ' . $this->cachedsize);
		header('cache-control: public, max-age=' . $max_age);
		header('last-modified: ' . gmdate('D, d M Y H:i:s', $this->cachedtime) . ' GMT');
		header('etag: ' . $eTag);
		echo base64_decode($this->cachedbody);
	}

	/**
	 * Returns the request's hashed filepath
	 *
	 * @access public
	 * @param string $request The request to get the path for
	 * @return string The hashed filepath for the specified request
	 */
	protected function getCachedPath($request)
	{
		return $this->cache . '/' . sha1($request . $this->secret);
	}

	/**
	 * Check whether the image exists in local cache or not
	 *
	 * @access protected
	 * @param string $request The image to check for in the cache
	 * @return bool Whether or not the requested image is cached
	 */
	protected function isCached($request)
	{
		return file_exists($this->getCachedPath($request));
	}

	/**
	 * Attempts to cache the image while validating it
	 *
	 * Redirects to the origin if
	 *    - the image couldn't be fetched
	 *    - the MIME type doesn't indicate an image
	 *    - the image is too large
	 *
	 * @access protected
	 * @param string $request The image to cache/validate
	 * @return bool Whether the specified image was cached
	 */
	protected function cacheImage($request)
	{
		$dest = $this->getCachedPath($request);
		$ext = strtolower(pathinfo(parse_url($request, PHP_URL_PATH), PATHINFO_EXTENSION));

		$image = fetch_web_data($request);

		// Looks like nobody was home
		if (empty($image))
			$this->redirectexit($request);

		// What kind of file did they give us?
		$finfo = finfo_open(FILEINFO_MIME_TYPE);
		$mime_type = finfo_buffer($finfo, $image);

		// SVG needs a little extra care
		if ($ext == 'svg' && $mime_type == 'text/plain')
			$mime_type = 'image/svg+xml';

		// Make sure the url is returning an image
		if (strpos($mime_type, 'image/') !== 0)
			$this->redirectexit($request);

		// Validate the filesize
		$size = strlen($image);
		if ($size > ($this->maxSize * 1024))
			$this->redirectexit($request);

		// Populate object for current serve execution (so you don't have to read it again...)
		$this->cachedtime = time();
		$this->cachedtype = $mime_type;
		$this->cachedsize = $size;
		$this->cachedbody = base64_encode($image);

		// Cache it for later
		return file_put_contents($dest, json_encode(array(
			'content_type' => $this->cachedtype,
			'size' => $this->cachedsize,
			'time' => $this->cachedtime,
			'body' => $this->cachedbody,
		))) !== false;
	}

	/**
	 * A helper function to redirect a request
	 *
	 * @access private
	 * @param string $request
	 */
	private function redirectexit($request)
	{
		header('Location: ' . un_htmlspecialchars($request), false, 301);
		exit;
	}

	/**
	 * Delete all old entries
	 *
	 * @access public
	 */
	public function housekeeping()
	{
		$path = $this->cache . '/';
		if ($handle = opendir($path))
		{
			while (false !== ($file = readdir($handle)))
			{
				$filelastmodified = filemtime($path . $file);

				if ((time() - $filelastmodified) > ($this->maxDays * 86400))
				{
					unlink($path . $file);
				}
			}

			closedir($handle);
		}
	}
}

if (SMF == 'PROXY')

{
	$proxy = new ProxyServer();
	$proxy->serve();
}

?>

1			<?php
2
3			/**
4			* This is a lightweight proxy for serving images, generally meant to be used alongside SSL
5			*
6			* Simple Machines Forum (SMF)
7			*
8			* @package SMF
9			* @author Simple Machines https://www.simplemachines.org
10			* @copyright 2020 Simple Machines and individual contributors
11			* @license https://www.simplemachines.org/about/smf/license.php BSD
12			*
13			* @version 2.1 RC2
14			*/
15
16			if (!defined('SMF'))
17			define('SMF', 'PROXY');
18
19			if (!defined('SMF_VERSION'))
20			define('SMF_VERSION', '2.1 RC2');
21
22			if (!defined('SMF_FULL_VERSION'))
23			define('SMF_FULL_VERSION', 'SMF ' . SMF_VERSION);
24
25			if (!defined('SMF_SOFTWARE_YEAR'))
26			define('SMF_SOFTWARE_YEAR', '2020');
27
28			if (!defined('JQUERY_VERSION'))
29			define('JQUERY_VERSION', '3.4.1');
30
31			if (!defined('POSTGRE_TITLE'))
32			define('POSTGRE_TITLE', 'PostgreSQL');
33
34			if (!defined('MYSQL_TITLE'))
35			define('MYSQL_TITLE', 'MySQL');
36
37			if (!defined('SMF_USER_AGENT'))
38			define('SMF_USER_AGENT', 'Mozilla/5.0 (' . php_uname('s') . ' ' . php_uname('m') . ') AppleWebKit/605.1.15 (KHTML, like Gecko) SMF/' . strtr(SMF_VERSION, ' ', '.'));
39
40			/**
41			* Class ProxyServer
42			*/
43			class ProxyServer
44			{
45			/** @var bool $enabled Whether or not this is enabled */
46			protected $enabled;
47
48			/** @var int $maxSize The maximum size for files to cache */
49			protected $maxSize;
50
51			/** @var string $secret A secret code used for hashing */
52			protected $secret;
53
54			/** @var string The cache directory */
55			protected $cache;
56
57			/** @var int $maxDays until entries get deleted */
58			protected $maxDays;
59
60			/** @var int $cachedtime time object cached */
61			protected $cachedtime;
62
63			/** @var string $cachedtype type of object cached */
64			protected $cachedtype;
65
66			/** @var int $cachedsize size of object cached */
67			protected $cachedsize;
68
69			/** @var string $cachedbody body of object cached */
70			protected $cachedbody;
71
72			/**
73			* Constructor, loads up the Settings for the proxy
74			*
75			* @access public
76			*/
77			public function __construct()
78			{
79			global $image_proxy_enabled, $image_proxy_maxsize, $image_proxy_secret, $cachedir, $sourcedir;
80
81			require_once(dirname(__FILE__) . '/Settings.php');
82			require_once($sourcedir . '/Subs.php');
83
84			// Turn off all error reporting; any extra junk makes for an invalid image.
85			error_reporting(0);
86
87			$this->enabled = (bool) $image_proxy_enabled;
88			$this->maxSize = (int) $image_proxy_maxsize;
89			$this->secret = (string) $image_proxy_secret;
90			$this->cache = $cachedir . '/images';
91			$this->maxDays = 5;
92			}
93
94			/**
95			* Checks whether the request is valid or not
96			*
97			* @access public
98			* @return bool Whether the request is valid
99			*/
100			public function checkRequest()
101			{
102			if (!$this->enabled)
103			return false;
104
105			// Try to create the image cache directory if it doesn't exist
106			if (!file_exists($this->cache))
107			if (!mkdir($this->cache) \|\| !copy(dirname($this->cache) . '/index.php', $this->cache . '/index.php'))
108			return false;
109
110			// Basic sanity check
111			$_GET['request'] = validate_iri($_GET['request']);
112
113			// We aren't going anywhere without these
114			if (empty($_GET['hash']) \|\| empty($_GET['request']))
115			return false;
116
117			$hash = $_GET['hash'];
118			$request = $_GET['request'];
119
120			if (hash_hmac('sha1', $request, $this->secret) != $hash)
121			return false;
122
123			// Ensure any non-ASCII characters in the URL are encoded correctly
124			$request = iri_to_url($request);
125
126			// Attempt to cache the request if it doesn't exist
127			if (!$this->isCached($request))
128			return $this->cacheImage($request);
129
130			return false;
131			}
132
133			/**
134			* Serves the request
135			*
136			* @access public
137			*/
138			public function serve()
139			{
140			$request = $_GET['request'];
141			// Did we get an error when trying to fetch the image
142			$response = $this->checkRequest();
143			if (!$response)
144			{
145			// Throw a 404
146			send_http_status(404);
147			exit;
			0 ignored issues – show Best Practice introduced 2019-04-06 07:27 UTC by Report Bug Copy Issue Report Using `exit` here is not recommended. In general, usage of exit should be done with care and only when running in a scripting context like a CLI script. Loading history...
148			}
149
150			// We should have a cached image at this point
151			$cached_file = $this->getCachedPath($request);
152
153			// Read from cache if you need to...
154			if ($this->cachedbody === null)
155			{
156			$cached = json_decode(file_get_contents($cached_file), true);
157			$this->cachedtime = $cached['time'];
158			$this->cachedtype = $cached['content_type'];
159			$this->cachedsize = $cached['size'];
160			$this->cachedbody = $cached['body'];
161			}
162
163			$time = time();
164
165			// Is the cache expired? Delete and reload.
166			if ($time - $this->cachedtime > ($this->maxDays * 86400))
167			{
168			@unlink($cached_file);
169			if ($this->checkRequest())
170			$this->serve();
171			$this->redirectexit($request);
172			}
173
174			$eTag = '"' . substr(sha1($request) . $this->cachedtime, 0, 64) . '"';
175			if (!empty($_SERVER['HTTP_IF_NONE_MATCH']) && strpos($_SERVER['HTTP_IF_NONE_MATCH'], $eTag) !== false)
176			{
177			send_http_status(304);
178			exit;
			0 ignored issues – show Best Practice introduced 2018-10-21 22:13 UTC by Report Bug Copy Issue Report Using `exit` here is not recommended. In general, usage of exit should be done with care and only when running in a scripting context like a CLI script. Loading history...
179			}
180
181			// Make sure we're serving an image
182			$contentParts = explode('/', !empty($this->cachedtype) ? $this->cachedtype : '');
183			if ($contentParts[0] != 'image')
184			exit;
			0 ignored issues – show Best Practice introduced 2018-10-21 22:13 UTC by Report Bug Copy Issue Report Using `exit` here is not recommended. In general, usage of exit should be done with care and only when running in a scripting context like a CLI script. Loading history...
185
186			$max_age = $time - $this->cachedtime + (5 * 86400);
187			header('content-type: ' . $this->cachedtype);
188			header('content-length: ' . $this->cachedsize);
189			header('cache-control: public, max-age=' . $max_age);
190			header('last-modified: ' . gmdate('D, d M Y H:i:s', $this->cachedtime) . ' GMT');
191			header('etag: ' . $eTag);
192			echo base64_decode($this->cachedbody);
193			}
194
195			/**
196			* Returns the request's hashed filepath
197			*
198			* @access public
199			* @param string $request The request to get the path for
200			* @return string The hashed filepath for the specified request
201			*/
202			protected function getCachedPath($request)
203			{
204			return $this->cache . '/' . sha1($request . $this->secret);
205			}
206
207			/**
208			* Check whether the image exists in local cache or not
209			*
210			* @access protected
211			* @param string $request The image to check for in the cache
212			* @return bool Whether or not the requested image is cached
213			*/
214			protected function isCached($request)
215			{
216			return file_exists($this->getCachedPath($request));
217			}
218
219			/**
220			* Attempts to cache the image while validating it
221			*
222			* Redirects to the origin if
223			* - the image couldn't be fetched
224			* - the MIME type doesn't indicate an image
225			* - the image is too large
226			*
227			* @access protected
228			* @param string $request The image to cache/validate
229			* @return bool Whether the specified image was cached
230			*/
231			protected function cacheImage($request)
232			{
233			$dest = $this->getCachedPath($request);
234			$ext = strtolower(pathinfo(parse_url($request, PHP_URL_PATH), PATHINFO_EXTENSION));
235
236			$image = fetch_web_data($request);
237
238			// Looks like nobody was home
239			if (empty($image))
240			$this->redirectexit($request);
241
242			// What kind of file did they give us?
243			$finfo = finfo_open(FILEINFO_MIME_TYPE);
244			$mime_type = finfo_buffer($finfo, $image);
245
246			// SVG needs a little extra care
247			if ($ext == 'svg' && $mime_type == 'text/plain')
248			$mime_type = 'image/svg+xml';
249
250			// Make sure the url is returning an image
251			if (strpos($mime_type, 'image/') !== 0)
252			$this->redirectexit($request);
253
254			// Validate the filesize
255			$size = strlen($image);
256			if ($size > ($this->maxSize * 1024))
257			$this->redirectexit($request);
258
259			// Populate object for current serve execution (so you don't have to read it again...)
260			$this->cachedtime = time();
261			$this->cachedtype = $mime_type;
262			$this->cachedsize = $size;
263			$this->cachedbody = base64_encode($image);
264
265			// Cache it for later
266			return file_put_contents($dest, json_encode(array(
267			'content_type' => $this->cachedtype,
268			'size' => $this->cachedsize,
269			'time' => $this->cachedtime,
270			'body' => $this->cachedbody,
271			))) !== false;
272			}
273
274			/**
275			* A helper function to redirect a request
276			*
277			* @access private
278			* @param string $request
279			*/
280			private function redirectexit($request)
281			{
282			header('Location: ' . un_htmlspecialchars($request), false, 301);
283			exit;
284			}
285
286			/**
287			* Delete all old entries
288			*
289			* @access public
290			*/
291			public function housekeeping()
292			{
293			$path = $this->cache . '/';
294			if ($handle = opendir($path))
295			{
296			while (false !== ($file = readdir($handle)))
297			{
298			$filelastmodified = filemtime($path . $file);
299
300			if ((time() - $filelastmodified) > ($this->maxDays * 86400))
301			{
302			unlink($path . $file);
303			}
304			}
305
306			closedir($handle);
307			}
308			}
309			}
310
311			if (SMF == 'PROXY')
			0 ignored issues – show introduced 2019-04-06 07:27 UTC by Report Bug Copy Issue Report The condition `SMF == 'PROXY'` is always `false`. Loading history...
312			{
313			$proxy = new ProxyServer();
314			$proxy->serve();
315			}
316
317			?>

SimpleMachines / SMF2.1

Pull Request — release-2.1 (#5917)

ProxyServer::checkRequest() B

Complexity

Size

Duplication

Importance

Duplication Side-by-Side

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