nextcloud/lib/util.php

1025 lines
29 KiB
PHP
Executable File

<?php
/**
* Class for utility functions
*
*/
class OC_Util {
public static $scripts=array();
public static $styles=array();
public static $headers=array();
private static $rootMounted=false;
private static $fsSetup=false;
public static $coreStyles=array();
public static $coreScripts=array();
/**
* @brief Can be set up
* @param string $user
* @return boolean
* @description configure the initial filesystem based on the configuration
*/
public static function setupFS( $user = '' ) {
//setting up the filesystem twice can only lead to trouble
if(self::$fsSetup) {
return false;
}
// If we are not forced to load a specific user we load the one that is logged in
if( $user == "" && OC_User::isLoggedIn()) {
$user = OC_User::getUser();
}
// load all filesystem apps before, so no setup-hook gets lost
if(!isset($RUNTIME_NOAPPS) || !$RUNTIME_NOAPPS) {
OC_App::loadApps(array('filesystem'));
}
// the filesystem will finish when $user is not empty,
// mark fs setup here to avoid doing the setup from loading
// OC_Filesystem
if ($user != '') {
self::$fsSetup=true;
}
$configDataDirectory = OC_Config::getValue( "datadirectory", OC::$SERVERROOT."/data" );
//first set up the local "root" storage
\OC\Files\Filesystem::initMounts();
if(!self::$rootMounted) {
\OC\Files\Filesystem::mount('\OC\Files\Storage\Local', array('datadir'=>$configDataDirectory), '/');
self::$rootMounted = true;
}
//if we aren't logged in, there is no use to set up the filesystem
if( $user != "" ) {
$quota = self::getUserQuota($user);
if ($quota !== \OC\Files\SPACE_UNLIMITED) {
\OC\Files\Filesystem::addStorageWrapper(function($mountPoint, $storage) use ($quota, $user) {
if ($mountPoint === '/' . $user . '/'){
return new \OC\Files\Storage\Wrapper\Quota(array('storage' => $storage, 'quota' => $quota));
} else {
return $storage;
}
});
}
$userDir = '/'.$user.'/files';
$userRoot = OC_User::getHome($user);
$userDirectory = $userRoot . '/files';
if( !is_dir( $userDirectory )) {
mkdir( $userDirectory, 0755, true );
}
//jail the user into his "home" directory
\OC\Files\Filesystem::init($user, $userDir);
$fileOperationProxy = new OC_FileProxy_FileOperations();
OC_FileProxy::register($fileOperationProxy);
OC_Hook::emit('OC_Filesystem', 'setup', array('user' => $user, 'user_dir' => $userDir));
}
return true;
}
public static function getUserQuota($user){
$userQuota = OC_Preferences::getValue($user, 'files', 'quota', 'default');
if($userQuota === 'default') {
$userQuota = OC_AppConfig::getValue('files', 'default_quota', 'none');
}
if($userQuota === 'none') {
return \OC\Files\SPACE_UNLIMITED;
}else{
return OC_Helper::computerFileSize($userQuota);
}
}
/**
* @return void
*/
public static function tearDownFS() {
\OC\Files\Filesystem::tearDown();
self::$fsSetup=false;
self::$rootMounted=false;
}
/**
* @brief get the current installed version of ownCloud
* @return array
*/
public static function getVersion() {
// hint: We only can count up. Reset minor/patchlevel when
// updating major/minor version number.
return array(5, 80, 07);
}
/**
* @brief get the current installed version string of ownCloud
* @return string
*/
public static function getVersionString() {
return '6.0 pre alpha';
}
/**
* @description get the current installed edition of ownCloud. There is the community
* edition that just returns an empty string and the enterprise edition
* that returns "Enterprise".
* @return string
*/
public static function getEditionString() {
return '';
}
/**
* @brief add a javascript file
*
* @param string $application
* @param filename $file
* @return void
*/
public static function addScript( $application, $file = null ) {
if ( is_null( $file )) {
$file = $application;
$application = "";
}
if ( !empty( $application )) {
self::$scripts[] = "$application/js/$file";
} else {
self::$scripts[] = "js/$file";
}
}
/**
* @brief add a css file
*
* @param string $application
* @param filename $file
* @return void
*/
public static function addStyle( $application, $file = null ) {
if ( is_null( $file )) {
$file = $application;
$application = "";
}
if ( !empty( $application )) {
self::$styles[] = "$application/css/$file";
} else {
self::$styles[] = "css/$file";
}
}
/**
* @brief Add a custom element to the header
* @param string $tag tag name of the element
* @param array $attributes array of attributes for the element
* @param string $text the text content for the element
* @return void
*/
public static function addHeader( $tag, $attributes, $text='') {
self::$headers[] = array(
'tag'=>$tag,
'attributes'=>$attributes,
'text'=>$text
);
}
/**
* @brief formats a timestamp in the "right" way
*
* @param int $timestamp
* @param bool $dateOnly option to omit time from the result
* @return string timestamp
* @description adjust to clients timezone if we know it
*/
public static function formatDate( $timestamp, $dateOnly=false) {
if(\OC::$session->exists('timezone')) {
$systemTimeZone = intval(date('O'));
$systemTimeZone = (round($systemTimeZone/100, 0)*60) + ($systemTimeZone%100);
$clientTimeZone = \OC::$session->get('timezone')*60;
$offset = $clientTimeZone - $systemTimeZone;
$timestamp = $timestamp + $offset*60;
}
$l = OC_L10N::get('lib');
return $l->l($dateOnly ? 'date' : 'datetime', $timestamp);
}
/**
* @brief check if the current server configuration is suitable for ownCloud
* @return array arrays with error messages and hints
*/
public static function checkServer() {
// Assume that if checkServer() succeeded before in this session, then all is fine.
if(\OC::$session->exists('checkServer_suceeded') && \OC::$session->get('checkServer_suceeded')) {
return array();
}
$errors = array();
$defaults = new \OC_Defaults();
$webServerRestart = false;
//check for database drivers
if(!(is_callable('sqlite_open') or class_exists('SQLite3'))
and !is_callable('mysql_connect')
and !is_callable('pg_connect')
and !is_callable('oci_connect')) {
$errors[] = array(
'error'=>'No database drivers (sqlite, mysql, or postgresql) installed.',
'hint'=>'' //TODO: sane hint
);
$webServerRestart = true;
}
//common hint for all file permissions error messages
$permissionsHint = 'Permissions can usually be fixed by '
.'<a href="' . $defaults->getDocBaseUrl() . '/server/5.0/admin_manual/installation/installation_source.html'
.'#set-the-directory-permissions" target="_blank">giving the webserver write access to the root directory</a>.';
// Check if config folder is writable.
if(!is_writable(OC::$SERVERROOT."/config/") or !is_readable(OC::$SERVERROOT."/config/")) {
$errors[] = array(
'error' => "Can't write into config directory",
'hint' => 'This can usually be fixed by '
.'<a href="' . $defaults->getDocBaseUrl() . '/server/5.0/admin_manual/installation/installation_source.html'
.'#set-the-directory-permissions" target="_blank">giving the webserver write access to the config directory</a>.'
);
}
// Check if there is a writable install folder.
if(OC_Config::getValue('appstoreenabled', true)) {
if( OC_App::getInstallPath() === null
|| !is_writable(OC_App::getInstallPath())
|| !is_readable(OC_App::getInstallPath()) ) {
$errors[] = array(
'error' => "Can't write into apps directory",
'hint' => 'This can usually be fixed by '
.'<a href="' . $defaults->getDocBaseUrl() . '/server/5.0/admin_manual/installation/installation_source.html'
.'#set-the-directory-permissions" target="_blank">giving the webserver write access to the apps directory</a> '
.'or disabling the appstore in the config file.'
);
}
}
$CONFIG_DATADIRECTORY = OC_Config::getValue( "datadirectory", OC::$SERVERROOT."/data" );
// Create root dir.
if(!is_dir($CONFIG_DATADIRECTORY)) {
$success=@mkdir($CONFIG_DATADIRECTORY);
if ($success) {
$errors = array_merge($errors, self::checkDataDirectoryPermissions($CONFIG_DATADIRECTORY));
} else {
$errors[] = array(
'error' => "Can't create data directory (".$CONFIG_DATADIRECTORY.")",
'hint' => 'This can usually be fixed by '
.'<a href="' . $defaults->getDocBaseUrl() . '/server/5.0/admin_manual/installation/installation_source.html'
.'#set-the-directory-permissions" target="_blank">giving the webserver write access to the root directory</a>.'
);
}
} else if(!is_writable($CONFIG_DATADIRECTORY) or !is_readable($CONFIG_DATADIRECTORY)) {
$errors[] = array(
'error'=>'Data directory ('.$CONFIG_DATADIRECTORY.') not writable by ownCloud',
'hint'=>$permissionsHint
);
} else {
$errors = array_merge($errors, self::checkDataDirectoryPermissions($CONFIG_DATADIRECTORY));
}
$moduleHint = "Please ask your server administrator to install the module.";
// check if all required php modules are present
if(!class_exists('ZipArchive')) {
$errors[] = array(
'error'=>'PHP module zip not installed.',
'hint'=>$moduleHint
);
$webServerRestart = true;
}
if(!class_exists('DOMDocument')) {
$errors[] = array(
'error' => 'PHP module dom not installed.',
'hint' => $moduleHint
);
$webServerRestart =true;
}
if(!function_exists('xml_parser_create')) {
$errors[] = array(
'error' => 'PHP module libxml not installed.',
'hint' => $moduleHint
);
$webServerRestart = true;
}
if(!function_exists('mb_detect_encoding')) {
$errors[] = array(
'error'=>'PHP module mb multibyte not installed.',
'hint'=>$moduleHint
);
$webServerRestart = true;
}
if(!function_exists('ctype_digit')) {
$errors[] = array(
'error'=>'PHP module ctype is not installed.',
'hint'=>$moduleHint
);
$webServerRestart = true;
}
if(!function_exists('json_encode')) {
$errors[] = array(
'error'=>'PHP module JSON is not installed.',
'hint'=>$moduleHint
);
$webServerRestart = true;
}
if(!extension_loaded('gd') || !function_exists('gd_info')) {
$errors[] = array(
'error'=>'PHP module GD is not installed.',
'hint'=>$moduleHint
);
$webServerRestart = true;
}
if(!function_exists('gzencode')) {
$errors[] = array(
'error'=>'PHP module zlib is not installed.',
'hint'=>$moduleHint
);
$webServerRestart = true;
}
if(!function_exists('iconv')) {
$errors[] = array(
'error'=>'PHP module iconv is not installed.',
'hint'=>$moduleHint
);
$webServerRestart = true;
}
if(!function_exists('simplexml_load_string')) {
$errors[] = array(
'error'=>'PHP module SimpleXML is not installed.',
'hint'=>$moduleHint
);
$webServerRestart = true;
}
if(floatval(phpversion()) < 5.3) {
$errors[] = array(
'error'=>'PHP 5.3 is required.',
'hint'=>'Please ask your server administrator to update PHP to version 5.3 or higher.'
.' PHP 5.2 is no longer supported by ownCloud and the PHP community.'
);
$webServerRestart = true;
}
if(!defined('PDO::ATTR_DRIVER_NAME')) {
$errors[] = array(
'error'=>'PHP PDO module is not installed.',
'hint'=>$moduleHint
);
$webServerRestart = true;
}
if (((strtolower(@ini_get('safe_mode')) == 'on')
|| (strtolower(@ini_get('safe_mode')) == 'yes')
|| (strtolower(@ini_get('safe_mode')) == 'true')
|| (ini_get("safe_mode") == 1 ))) {
$errors[] = array(
'error'=>'PHP Safe Mode is enabled. ownCloud requires that it is disabled to work properly.',
'hint'=>'PHP Safe Mode is a deprecated and mostly useless setting that should be disabled. '
.'Please ask your server administrator to disable it in php.ini or in your webserver config.'
);
$webServerRestart = true;
}
if (get_magic_quotes_gpc() == 1 ) {
$errors[] = array(
'error'=>'Magic Quotes is enabled. ownCloud requires that it is disabled to work properly.',
'hint'=>'Magic Quotes is a deprecated and mostly useless setting that should be disabled. '
.'Please ask your server administrator to disable it in php.ini or in your webserver config.'
);
$webServerRestart = true;
}
if($webServerRestart) {
$errors[] = array(
'error'=>'PHP modules have been installed, but they are still listed as missing?',
'hint'=>'Please ask your server administrator to restart the web server.'
);
}
// Cache the result of this function
\OC::$session->set('checkServer_suceeded', count($errors) == 0);
return $errors;
}
/**
* @brief check if there are still some encrypted files stored
* @return boolean
*/
public static function encryptedFiles() {
//check if encryption was enabled in the past
$encryptedFiles = false;
if (OC_App::isEnabled('files_encryption') === false) {
$view = new OC\Files\View('/' . OCP\User::getUser());
if ($view->file_exists('/files_encryption/keyfiles')) {
$encryptedFiles = true;
}
}
return $encryptedFiles;
}
/**
* @brief Check for correct file permissions of data directory
* @paran string $dataDirectory
* @return array arrays with error messages and hints
*/
public static function checkDataDirectoryPermissions($dataDirectory) {
$errors = array();
if (self::runningOnWindows()) {
//TODO: permissions checks for windows hosts
} else {
$permissionsModHint = 'Please change the permissions to 0770 so that the directory'
.' cannot be listed by other users.';
$perms = substr(decoct(@fileperms($dataDirectory)), -3);
if (substr($perms, -1) != '0') {
OC_Helper::chmodr($dataDirectory, 0770);
clearstatcache();
$perms = substr(decoct(@fileperms($dataDirectory)), -3);
if (substr($perms, 2, 1) != '0') {
$errors[] = array(
'error' => 'Data directory ('.$dataDirectory.') is readable for other users',
'hint' => $permissionsModHint
);
}
}
}
return $errors;
}
/**
* @return void
*/
public static function displayLoginPage($errors = array()) {
$parameters = array();
foreach( $errors as $key => $value ) {
$parameters[$value] = true;
}
if (!empty($_POST['user'])) {
$parameters["username"] = $_POST['user'];
$parameters['user_autofocus'] = false;
} else {
$parameters["username"] = '';
$parameters['user_autofocus'] = true;
}
if (isset($_REQUEST['redirect_url'])) {
$redirectUrl = $_REQUEST['redirect_url'];
$parameters['redirect_url'] = urlencode($redirectUrl);
}
$parameters['alt_login'] = OC_App::getAlternativeLogIns();
OC_Template::printGuestPage("", "login", $parameters);
}
/**
* @brief Check if the app is enabled, redirects to home if not
* @return void
*/
public static function checkAppEnabled($app) {
if( !OC_App::isEnabled($app)) {
header( 'Location: '.OC_Helper::linkToAbsolute( '', 'index.php' ));
exit();
}
}
/**
* Check if the user is logged in, redirects to home if not. With
* redirect URL parameter to the request URI.
* @return void
*/
public static function checkLoggedIn() {
// Check if we are a user
if( !OC_User::isLoggedIn()) {
header( 'Location: '.OC_Helper::linkToAbsolute( '', 'index.php',
array('redirectUrl' => OC_Request::requestUri())
));
exit();
}
}
/**
* @brief Check if the user is a admin, redirects to home if not
* @return void
*/
public static function checkAdminUser() {
if( !OC_User::isAdminUser(OC_User::getUser())) {
header( 'Location: '.OC_Helper::linkToAbsolute( '', 'index.php' ));
exit();
}
}
/**
* @brief Check if the user is a subadmin, redirects to home if not
* @return array $groups where the current user is subadmin
*/
public static function checkSubAdminUser() {
if(!OC_SubAdmin::isSubAdmin(OC_User::getUser())) {
header( 'Location: '.OC_Helper::linkToAbsolute( '', 'index.php' ));
exit();
}
return true;
}
/**
* @brief Redirect to the user default page
* @return void
*/
public static function redirectToDefaultPage() {
if(isset($_REQUEST['redirect_url'])) {
$location = OC_Helper::makeURLAbsolute(urldecode($_REQUEST['redirect_url']));
}
else if (isset(OC::$REQUESTEDAPP) && !empty(OC::$REQUESTEDAPP)) {
$location = OC_Helper::linkToAbsolute( OC::$REQUESTEDAPP, 'index.php' );
} else {
$defaultPage = OC_Appconfig::getValue('core', 'defaultpage');
if ($defaultPage) {
$location = OC_Helper::makeURLAbsolute(OC::$WEBROOT.'/'.$defaultPage);
} else {
$location = OC_Helper::linkToAbsolute( 'files', 'index.php' );
}
}
OC_Log::write('core', 'redirectToDefaultPage: '.$location, OC_Log::DEBUG);
header( 'Location: '.$location );
exit();
}
/**
* @brief get an id unique for this instance
* @return string
*/
public static function getInstanceId() {
$id = OC_Config::getValue('instanceid', null);
if(is_null($id)) {
// We need to guarantee at least one letter in instanceid so it can be used as the session_name
$id = 'oc' . self::generateRandomBytes(10);
OC_Config::setValue('instanceid', $id);
}
return $id;
}
/**
* @brief Static lifespan (in seconds) when a request token expires.
* @see OC_Util::callRegister()
* @see OC_Util::isCallRegistered()
* @description
* Also required for the client side to compute the point in time when to
* request a fresh token. The client will do so when nearly 97% of the
* time span coded here has expired.
*/
public static $callLifespan = 3600; // 3600 secs = 1 hour
/**
* @brief Register an get/post call. Important to prevent CSRF attacks.
* @todo Write howto: CSRF protection guide
* @return $token Generated token.
* @description
* Creates a 'request token' (random) and stores it inside the session.
* Ever subsequent (ajax) request must use such a valid token to succeed,
* otherwise the request will be denied as a protection against CSRF.
* The tokens expire after a fixed lifespan.
* @see OC_Util::$callLifespan
* @see OC_Util::isCallRegistered()
*/
public static function callRegister() {
// Check if a token exists
if(!\OC::$session->exists('requesttoken')) {
// No valid token found, generate a new one.
$requestToken = self::generateRandomBytes(20);
\OC::$session->set('requesttoken', $requestToken);
} else {
// Valid token already exists, send it
$requestToken = \OC::$session->get('requesttoken');
}
return($requestToken);
}
/**
* @brief Check an ajax get/post call if the request token is valid.
* @return boolean False if request token is not set or is invalid.
* @see OC_Util::$callLifespan
* @see OC_Util::callRegister()
*/
public static function isCallRegistered() {
if(!\OC::$session->exists('requesttoken')) {
return false;
}
if(isset($_GET['requesttoken'])) {
$token = $_GET['requesttoken'];
} elseif(isset($_POST['requesttoken'])) {
$token = $_POST['requesttoken'];
} elseif(isset($_SERVER['HTTP_REQUESTTOKEN'])) {
$token = $_SERVER['HTTP_REQUESTTOKEN'];
} else {
//no token found.
return false;
}
// Check if the token is valid
if($token !== \OC::$session->get('requesttoken')) {
// Not valid
return false;
} else {
// Valid token
return true;
}
}
/**
* @brief Check an ajax get/post call if the request token is valid. exit if not.
* @todo Write howto
* @return void
*/
public static function callCheck() {
if(!OC_Util::isCallRegistered()) {
exit();
}
}
/**
* @brief Public function to sanitize HTML
*
* This function is used to sanitize HTML and should be applied on any
* string or array of strings before displaying it on a web page.
*
* @param string|array of strings
* @return array with sanitized strings or a single sanitized string, depends on the input parameter.
*/
public static function sanitizeHTML( &$value ) {
if (is_array($value)) {
array_walk_recursive($value, 'OC_Util::sanitizeHTML');
} else {
//Specify encoding for PHP<5.4
$value = htmlentities((string)$value, ENT_QUOTES, 'UTF-8');
}
return $value;
}
/**
* @brief Public function to encode url parameters
*
* This function is used to encode path to file before output.
* Encoding is done according to RFC 3986 with one exception:
* Character '/' is preserved as is.
*
* @param string $component part of URI to encode
* @return string
*/
public static function encodePath($component) {
$encoded = rawurlencode($component);
$encoded = str_replace('%2F', '/', $encoded);
return $encoded;
}
/**
* @brief Check if the htaccess file is working
* @return bool
* @description Check if the htaccess file is working by creating a test
* file in the data directory and trying to access via http
*/
public static function isHtAccessWorking() {
// testdata
$fileName = '/htaccesstest.txt';
$testContent = 'testcontent';
// creating a test file
$testFile = OC_Config::getValue( "datadirectory", OC::$SERVERROOT."/data" ).'/'.$fileName;
if(file_exists($testFile)) {// already running this test, possible recursive call
return false;
}
$fp = @fopen($testfile, 'w');
@fwrite($fp, $testcontent);
@fclose($fp);
// accessing the file via http
$url = OC_Helper::makeURLAbsolute(OC::$WEBROOT.'/data'.$fileName);
$fp = @fopen($url, 'r');
$content=@fread($fp, 2048);
@fclose($fp);
// cleanup
@unlink($testfile);
// does it work ?
if($content==$testContent) {
return false;
} else {
return true;
}
}
/**
* @brief test if webDAV is working properly
* @return bool
* @description
* The basic assumption is that if the server returns 401/Not Authenticated for an unauthenticated PROPFIND
* the web server it self is setup properly.
*
* Why not an authenticated PROPFIND and other verbs?
* - We don't have the password available
* - We have no idea about other auth methods implemented (e.g. OAuth with Bearer header)
*
*/
public static function isWebDAVWorking() {
if (!function_exists('curl_init')) {
return true;
}
$settings = array(
'baseUri' => OC_Helper::linkToRemote('webdav'),
);
// save the old timeout so that we can restore it later
$oldTimeout = ini_get("default_socket_timeout");
// use a 5 sec timeout for the check. Should be enough for local requests.
ini_set("default_socket_timeout", 5);
$client = new \Sabre_DAV_Client($settings);
// for this self test we don't care if the ssl certificate is self signed and the peer cannot be verified.
$client->setVerifyPeer(false);
$return = true;
try {
// test PROPFIND
$client->propfind('', array('{DAV:}resourcetype'));
} catch (\Sabre_DAV_Exception_NotAuthenticated $e) {
$return = true;
} catch (\Exception $e) {
OC_Log::write('core', 'isWebDAVWorking: NO - Reason: '.$e->getMessage(). ' ('.get_class($e).')', OC_Log::WARN);
$return = false;
}
// restore the original timeout
ini_set("default_socket_timeout", $oldTimeout);
return $return;
}
/**
* Check if the setlocal call does not work. This can happen if the right
* local packages are not available on the server.
* @return bool
*/
public static function isSetLocaleWorking() {
// setlocale test is pointless on Windows
if (OC_Util::runningOnWindows() ) {
return true;
}
$result = setlocale(LC_ALL, 'en_US.UTF-8', 'en_US.UTF8');
if($result == false) {
return false;
}
return true;
}
/**
* @brief Check if the PHP module fileinfo is loaded.
* @return bool
*/
public static function fileInfoLoaded() {
return function_exists('finfo_open');
}
/**
* @brief Check if the ownCloud server can connect to the internet
* @return bool
*/
public static function isInternetConnectionWorking() {
// in case there is no internet connection on purpose return false
if (self::isInternetConnectionEnabled() === false) {
return false;
}
// try to connect to owncloud.org to see if http connections to the internet are possible.
$connected = @fsockopen("www.owncloud.org", 80);
if ($connected) {
fclose($connected);
return true;
} else {
// second try in case one server is down
$connected = @fsockopen("apps.owncloud.com", 80);
if ($connected) {
fclose($connected);
return true;
} else {
return false;
}
}
}
/**
* @brief Check if the connection to the internet is disabled on purpose
* @return bool
*/
public static function isInternetConnectionEnabled(){
return \OC_Config::getValue("has_internet_connection", true);
}
/**
* @brief clear all levels of output buffering
* @return void
*/
public static function obEnd(){
while (ob_get_level()) {
ob_end_clean();
}
}
/**
* @brief Generates a cryptographic secure pseudo-random string
* @param Int $length of the random string
* @return String
* Please also update secureRNGAvailable if you change something here
*/
public static function generateRandomBytes($length = 30) {
// Try to use openssl_random_pseudo_bytes
if (function_exists('openssl_random_pseudo_bytes')) {
$pseudoByte = bin2hex(openssl_random_pseudo_bytes($length, $strong));
if($strong == true) {
return substr($pseudoByte, 0, $length); // Truncate it to match the length
}
}
// Try to use /dev/urandom
if (!self::runningOnWindows()) {
$fp = @file_get_contents('/dev/urandom', false, null, 0, $length);
if ($fp !== false) {
$string = substr(bin2hex($fp), 0, $length);
return $string;
}
}
// Fallback to mt_rand()
$characters = '0123456789';
$characters .= 'abcdefghijklmnopqrstuvwxyz';
$charactersLength = strlen($characters)-1;
$pseudoByte = "";
// Select some random characters
for ($i = 0; $i < $length; $i++) {
$pseudoByte .= $characters[mt_rand(0, $charactersLength)];
}
return $pseudoByte;
}
/**
* @brief Checks if a secure random number generator is available
* @return bool
*/
public static function secureRNGAvailable() {
// Check openssl_random_pseudo_bytes
if(function_exists('openssl_random_pseudo_bytes')) {
openssl_random_pseudo_bytes(1, $strong);
if($strong == true) {
return true;
}
}
// Check /dev/urandom
if (!self::runningOnWindows()) {
$fp = @file_get_contents('/dev/urandom', false, null, 0, 1);
if ($fp !== false) {
return true;
}
}
return false;
}
/**
* @Brief Get file content via curl.
* @param string $url Url to get content
* @return string of the response or false on error
* This function get the content of a page via curl, if curl is enabled.
* If not, file_get_element is used.
*/
public static function getUrlContent($url){
if (function_exists('curl_init')) {
$curl = curl_init();
curl_setopt($curl, CURLOPT_HEADER, 0);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($curl, CURLOPT_CONNECTTIMEOUT, 10);
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($curl, CURLOPT_MAXREDIRS, 10);
curl_setopt($curl, CURLOPT_USERAGENT, "ownCloud Server Crawler");
if(OC_Config::getValue('proxy', '') != '') {
curl_setopt($curl, CURLOPT_PROXY, OC_Config::getValue('proxy'));
}
if(OC_Config::getValue('proxyuserpwd', '') != '') {
curl_setopt($curl, CURLOPT_PROXYUSERPWD, OC_Config::getValue('proxyuserpwd'));
}
$data = curl_exec($curl);
curl_close($curl);
} else {
$contextArray = null;
if(OC_Config::getValue('proxy', '') != '') {
$contextArray = array(
'http' => array(
'timeout' => 10,
'proxy' => OC_Config::getValue('proxy')
)
);
} else {
$contextArray = array(
'http' => array(
'timeout' => 10
)
);
}
$ctx = stream_context_create(
$contextArray
);
$data = @file_get_contents($url, 0, $ctx);
}
return $data;
}
/**
* @return bool - well are we running on windows or not
*/
public static function runningOnWindows() {
return (substr(PHP_OS, 0, 3) === "WIN");
}
/**
* Handles the case that there may not be a theme, then check if a "default"
* theme exists and take that one
* @return string the theme
*/
public static function getTheme() {
$theme = OC_Config::getValue("theme", '');
if($theme === '') {
if(is_dir(OC::$SERVERROOT . '/themes/default')) {
$theme = 'default';
}
}
return $theme;
}
/**
* @brief Clear the opcode cache if one exists
* This is necessary for writing to the config file
* in case the opcode cache does not re-validate files
* @return void
*/
public static function clearOpcodeCache() {
// APC
if (function_exists('apc_clear_cache')) {
apc_clear_cache();
}
// Zend Opcache
if (function_exists('accelerator_reset')) {
accelerator_reset();
}
// XCache
if (function_exists('xcache_clear_cache')) {
xcache_clear_cache(XC_TYPE_VAR, 0);
}
// Opcache (PHP >= 5.5)
if (function_exists('opcache_reset')) {
opcache_reset();
}
}
/**
* Normalize a unicode string
* @param string $value a not normalized string
* @return bool|string
*/
public static function normalizeUnicode($value) {
if(class_exists('Patchwork\PHP\Shim\Normalizer')) {
$normalizedValue = \Patchwork\PHP\Shim\Normalizer::normalize($value);
if($normalizedValue === false) {
\OC_Log::write( 'core', 'normalizing failed for "' . $value . '"', \OC_Log::WARN);
} else {
$value = $normalizedValue;
}
}
return $value;
}
/**
* @return string
*/
public static function basename($file) {
$file = rtrim($file, '/');
$t = explode('/', $file);
return array_pop($t);
}
}