-
Notifications
You must be signed in to change notification settings - Fork 5
/
ClamavPlugin.inc.php
401 lines (363 loc) · 12.5 KB
/
ClamavPlugin.inc.php
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
<?php
/**
* @file plugins/generic/clamav/ClamavPlugin.inc.php
*
* Copyright (c) 2018 University of Pittsburgh
* Distributed under the GNU GPL v2 or later. For full terms see the LICENSE file.
*
* @class ClamavPlugin
* @ingroup plugins_generic_clamav
*
* @brief ClamAV plugin class
*/
import('lib.pkp.classes.plugins.GenericPlugin');
class ClamScanFailureException extends Exception {};
class ClamavPlugin extends GenericPlugin {
const TYPE_SOCKET = 'socket';
const TYPE_EXECUTABLE = 'executable';
const TIMEOUT_DEFAULT = 30;
const UNSCANNED_DEFAULT = 'allow';
const UNSCANNED_ALLOW = 'allow';
const UNSCANNED_BLOCK = 'block';
/**
* Called as a plugin is registered to the registry
* @param $category String Name of category plugin was registered to
* @return boolean True iff plugin initialized successfully; if false,
* the plugin will not be registered.
*/
function register($category, $path, $mainContextId = NULL) {
$success = parent::register($category, $path, $mainContextId);
if (!Config::getVar('general', 'installed') || defined('RUNNING_UPGRADE'))
return true;
if ($success && $this->getEnabled()) {
// Enable Clam AV's preprocessing of uploaded files
HookRegistry::register('SubmissionFile::validate', array($this, 'clamscanHandleUpload'));
// Create handler for AJAX call
HookRegistry::register('LoadHandler', array($this, 'setPageHandler'));
}
return $success;
}
/**
* Get the display name of this plugin.
* @return String
*/
function getDisplayName() {
return __('plugins.generic.clamav.displayName');
}
/**
* Get a description of the plugin.
* @return String
*/
function getDescription() {
return __('plugins.generic.clamav.description');
}
/**
* Site-wide plugins should override this function to return true.
*
* @return boolean
*/
function isSitePlugin() {
return true;
}
/**
* Backwards-compatible method to retrieve the current context across
* multiple versions of PKP applicatiosn
* @return
*/
function _getBackwardsCompatibleContext() {
if(method_exists('Application', 'get')) {
// OJS 3.2 and later
$request = Application::get()->getRequest();
$context = $request->getContext();
} else {
// OJS 3.1.2 and earlier
$context = Request::getContext();
}
return $context;
}
/**
* @copydoc Plugin::getActions()
*/
function getActions($request, $verb) {
$router = $request->getRouter();
import('lib.pkp.classes.linkAction.request.AjaxModal');
return array_merge(
$this->getEnabled() ? array(
new LinkAction(
'settings', new AjaxModal(
$router->url($request, null, null, 'manage', null, array('verb' => 'settings', 'plugin' => $this->getName(), 'category' => 'generic')), $this->getDisplayName()
), __('manager.plugins.settings'), null
),
) : array(), parent::getActions($request, $verb)
);
}
/**
* @copydoc Plugin::manage()
*/
function manage($args, $request) {
switch ($request->getUserVar('verb')) {
case 'settings':
$contextID = (!is_null($this->_getBackwardsCompatibleContext()) ? $this->_getBackwardsCompatibleContext()->getId() : CONTEXT_SITE);
AppLocale::requireComponents(LOCALE_COMPONENT_APP_COMMON, LOCALE_COMPONENT_PKP_MANAGER);
$templateMgr = TemplateManager::getManager($request);
$templateMgr->register_function('plugin_url', array($this, 'smartyPluginUrl'));
$this->import('ClamavSettingsForm');
$form = new ClamavSettingsForm($this, $contextID);
if ($request->getUserVar('save')) {
$form->readInputData();
if ($form->validate()) {
$form->execute();
return new JSONMessage(true);
}
} else {
$form->initData($request);
}
return new JSONMessage(true, $form->fetch($request));
default:
assert(false);
return false;
}
return parent::manage($args, $request);
}
/**
* @copydoc PKPPlugin::getTemplatePath
*/
function getTemplatePath($inCore = false) {
if(method_exists($this, 'getTemplateResource')) {
// OJS 3.1.2 and later
return parent::getTemplatePath($inCore);
} else {
// OJS 3.1.1 and earlier 3.x releases
return parent::getTemplatePath($inCore) . 'templates' . DIRECTORY_SEPARATOR;
}
}
/**
* Get the clam version
* @param $path string Optional path to check. If not provided, the current setting value is used.
* @param $type string Type of connection to be used: executable or socket.
* @return string
* */
function getClamVersion($path = '', $type=self::TYPE_EXECUTABLE) {
if ($path === '') {
$path = $this->getSetting(CONTEXT_SITE, 'clamavPath');
}
if ($type === self::TYPE_EXECUTABLE && !empty($path) && is_executable($path)) {
$version = exec($path . ' --version');
if (preg_match('/^ClamAV .*/', $version)) {
return $version;
}
} else if ($type === self::TYPE_SOCKET && !empty($path)) {
$output = '';
$errno = 0;
$errorMessage = "";
$clamDaemon = stream_socket_client("$path", $errno, $errorMessage);
if ($clamDaemon) {
// clamd wants non-blocking socket connections
stream_set_blocking($clamDaemon, false);
// get version of clamd
// \0 is null character.
stream_socket_sendto($clamDaemon, "zVERSION\0");
$output = $this->_clamDaemonShortPolling($clamDaemon);
return $output;
}
}
return '';
}
/**
* Private helper method to scan a file using the clamscan executable, returning a virus message if matched
* @param $uploadedFile string Path to the uploaded file in OJS's files directory
* @throws ClamScanFailureException
* @return boolean|string
*/
function _clamscanFile($uploadedFile) {
if ($this->getClamVersion() && !empty($uploadedFile)) {
$output = "";
$exitCode = "";
$clamAVPath = $this->getSetting(CONTEXT_SITE, 'clamavPath');
$scan = exec($clamAVPath . ' --no-summary -i ' . $uploadedFile, $output, $exitCode);
//process the result
preg_match('/:(.*)/',$output[0],$matches);
$virusID=trim($matches[1]);
switch ($exitCode) {
//clean
case 0:
return false;
//virus found!
case 1:
return $virusID;
//failed to scan
case 2:
default:
}
}
throw new ClamScanFailureException("ClamAV failed to scan the file");
}
/**
* Private helper method to scan a file using the clamav daemon
* @param $uploadedFile string The path to the file to be scanned
* @return boolean|string
*/
function _clamDaemonFile($uploadedFile) {
$clamavSocketPath = $this->getSetting(CONTEXT_SITE, 'clamavSocketPath');
$maxInstreamSize = 1024; // TODO: need to universalize this based on a plugin setting
$output = "";
$errno = 0;
$errorMessage = "";
// stream_socket_client() seems to be preferred over older socket
// connections nowadays
$clamDaemon = stream_socket_client("$clamavSocketPath", $errno, $errorMessage);
// open file for reading in binary mode
$tmpFile = fopen($uploadedFile, 'rb');
if ($clamDaemon && $tmpFile) {
// clamd wants non-blocking socket connections
stream_set_blocking($clamDaemon, false);
// begin IDSESSION with clamd. z prefix indicates null delimiter.
// \0 is null character.
stream_socket_sendto($clamDaemon, "zIDSESSION\0");
/*
* INSTREAM begins data stream for virus scanning. Data is sent
* in chunks, with format <length><data> where <length> is the size
* of the following data in bytes expressed as a 4-byte unsigned
* integer in network byte order.
*
* We're using pack() to generate the big-endian-formatted numbers.
*
* As per the clamd man page, clamd requires a non-blocking
* connection which means we need to roll our own polling solution--
* this is managed by _clamDaemonShortPolling().
*/
stream_socket_sendto($clamDaemon, "zINSTREAM\0");
while (!feof($tmpFile)) {
$data = fread($tmpFile, $maxInstreamSize);
$package = pack("N", strlen($data)).$data;
stream_socket_sendto($clamDaemon, $package);
}
// terminating INSTREAM with zero-length chunk
$data = pack("N", "");
stream_socket_sendto($clamDaemon, $data);
// wait for output
$output = $this->_clamDaemonShortPolling($clamDaemon);
// closing IDSESSION
stream_socket_sendto($clamDaemon, "nEND\0");
fclose($tmpFile);
fclose($clamDaemon);
if($output['safe'] === true) {
return false;
}
if($output['safe'] === false) {
return $output['message'];
}
}
throw new ClamScanFailureException("ClamAV Daemon failed to scan the file");
}
/**
* Private helper method to manage short polling a socket and return output
* @param $socket stream resource The streaming socket resource.
* @param $delay int Time between short polls, measured in nanoseconds
* @param $intervals int Number of intervals to check; after $intervals checks, return.
* @throws ClamScanFailureException
* @return string
*/
function _clamDaemonShortPolling($socket, $delay = 100000000, $intervals = 10) {
// author's note: cludge cludge cludge cludge. TODO: look into long polling for unix sockets?
$output = "";
$intervals = $this->getSetting(CONTEXT_SITE, 'clamavSocketTimeout')*10;
$failover = $this->getSetting(CONTEXT_SITE, 'allowUnscannedFiles');
for ($i = 0; $i < $intervals; $i++) {
// sleep() does not accept fractional seconds and usleep uses a surprising amount of CPU, leaving us with time_nanosleep().
time_nanosleep(0, $delay);
$output = stream_get_contents($socket);
if ($output !== "") {
if($output == "1: stream: OK\0") {
return Array('safe' => true, 'message' => $output);
} else {
return Array('safe' => false, 'message' => substr($output, 11));
}
}
throw new ClamScanFailureException("ClamAV failed to scan the file");
}
}
/**
* Hook callback: scan an uploaded file with ClamAV
* @see submissionfilesuploadform::validate()
*/
function clamscanHandleUpload($hookName, $args) {
$fileId = $args[2]['fileId'];
$props = $args[2];
$allowedLocales = $args[3];
$file = Services::get('file')->get($fileId);
$path = $file->path;
$uploadedFile = Config::getVar('files', 'files_dir') . '/' . $path;
//scan for viruses if file exists
if (null !== $file) {
$useSocket = $this->getSetting(CONTEXT_SITE, 'clamavUseSocket');
import('lib.pkp.classes.validation.ValidatorFactory');
$schemaService = Services::get('schema');
$rejectionMessage = array();
$validator = \ValidatorFactory::make(
$props,
$schemaService->getValidationRules(SCHEMA_SUBMISSION_FILE, $allowedLocales),
$rejectionMessage
);
try {
if ($useSocket === true) {
$message = $this->_clamDaemonFile($uploadedFile);
} else {
$message = $this->_clamscanFile($uploadedFile);
}
//No viruses found! Continue with submission
if ($message === false) {
return false;
} else {
//ClamAV reported a virus or failed to complete the scan
//Prepare to notify the user and halt the upload process
$rejectionMessage = ["threatname"=>$message];
//If Clam found a virus, it will return the signature name as a string
if ($message == true) {
//create a user notification
$validator->errors()->add('clamAV::virusDetected', __('plugins.generic.clamav.uploadBlocked',$rejectionMessage));
}
}
}
//Scanning errors will generate a custom exception
catch (ClamScanFailureException $e){
//Couldn't scan, but ClamAV plugin settings are permissive, continue with submission anyway
$setting=$this->getSetting(CONTEXT_SITE, 'allowUnscannedFiles');
if ( $this->getSetting(CONTEXT_SITE, 'allowUnscannedFiles')===self::UNSCANNED_ALLOW) {
return false;
} else {
//Otherwise notify the user that there was an error
//the user will see the general error message from the locale file
$validator->errors()->add('clamAV::failedToScan', __('plugins.generic.clamav.error'));
}
}
//The file is considered unsafe. Interrupt submission process and clean up the working copy/metadata
$errors = $schemaService->formatValidationErrors($validator->errors(), $schemaService->get(SCHEMA_SUBMISSION_FILE), $allowedLocales);
if ($args[0]===null){
$args[0]=$errors;
} elseif (is_array($args[0])) {
array_push($args[0],$errors);
}
// returning true aborts processing
return true;
}
}
/**
* Route requests for the clam version to custom page handler
*
* @see PKPPageRouter::route()
* @param $hookName string
* @param $params array
*/
public function setPageHandler($hookName, $params) {
$page = $params[0];
$op = $params[1];
if ($this->getEnabled() && $page === 'clamav' && $op === 'clamavVersion') {
$this->import('ClamavVersionHandler');
define('HANDLER_CLASS', 'ClamavVersionHandler');
return true;
}
return false;
}
}
?>