diff --git a/include/network.php b/include/network.php
index 73fa80f98..7798fd9cd 100644
--- a/include/network.php
+++ b/include/network.php
@@ -9,1079 +9,111 @@ use Friendica\Core\System;
 use Friendica\Core\Config;
 use Friendica\Network\Probe;
 use Friendica\Object\Image;
+use Friendica\Util\Network;
 use Friendica\Util\XML;
 
-/**
- * @brief Curl wrapper
- *
- * If binary flag is true, return binary results.
- * Set the cookiejar argument to a string (e.g. "/tmp/friendica-cookies.txt")
- * to preserve cookies from one request to the next.
- *
- * @param string  $url            URL to fetch
- * @param boolean $binary         default false
- *                                TRUE if asked to return binary results (file download)
- * @param integer $redirects      The recursion counter for internal use - default 0
- * @param integer $timeout        Timeout in seconds, default system config value or 60 seconds
- * @param string  $accept_content supply Accept: header with 'accept_content' as the value
- * @param string  $cookiejar      Path to cookie jar file
- *
- * @return string The fetched content
- */
 function fetch_url($url, $binary = false, &$redirects = 0, $timeout = 0, $accept_content = null, $cookiejar = 0)
 {
-	$ret = z_fetch_url(
-		$url,
-		$binary,
-		$redirects,
-		['timeout'=>$timeout,
-		'accept_content'=>$accept_content,
-		'cookiejar'=>$cookiejar
-		]
-	);
-
-	return($ret['body']);
+	return Network::fetchURL($url, $binary, $redirects, $timeout, $accept_content, $cookiejar);
 }
 
-/**
- * @brief fetches an URL.
- *
- * @param string  $url       URL to fetch
- * @param boolean $binary    default false
- *                           TRUE if asked to return binary results (file download)
- * @param int     $redirects The recursion counter for internal use - default 0
- * @param array   $opts      (optional parameters) assoziative array with:
- *                           'accept_content' => supply Accept: header with 'accept_content' as the value
- *                           'timeout' => int Timeout in seconds, default system config value or 60 seconds
- *                           'http_auth' => username:password
- *                           'novalidate' => do not validate SSL certs, default is to validate using our CA list
- *                           'nobody' => only return the header
- *                           'cookiejar' => path to cookie jar file
- *
- * @return array an assoziative array with:
- *    int 'return_code' => HTTP return code or 0 if timeout or failure
- *    boolean 'success' => boolean true (if HTTP 2xx result) or false
- *    string 'redirect_url' => in case of redirect, content was finally retrieved from this URL
- *    string 'header' => HTTP headers
- *    string 'body' => fetched content
- */
 function z_fetch_url($url, $binary = false, &$redirects = 0, $opts = [])
 {
-	$ret = ['return_code' => 0, 'success' => false, 'header' => '', 'info' => '', 'body' => ''];
-
-	$stamp1 = microtime(true);
-
-	$a = get_app();
-
-	if (blocked_url($url)) {
-		logger('z_fetch_url: domain of ' . $url . ' is blocked', LOGGER_DATA);
-		return $ret;
-	}
-
-	$ch = @curl_init($url);
-
-	if (($redirects > 8) || (!$ch)) {
-		return $ret;
-	}
-
-	@curl_setopt($ch, CURLOPT_HEADER, true);
-
-	if (x($opts, "cookiejar")) {
-		curl_setopt($ch, CURLOPT_COOKIEJAR, $opts["cookiejar"]);
-		curl_setopt($ch, CURLOPT_COOKIEFILE, $opts["cookiejar"]);
-	}
-
-	// These settings aren't needed. We're following the location already.
-	//	@curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
-	//	@curl_setopt($ch, CURLOPT_MAXREDIRS, 5);
-
-	if (x($opts, 'accept_content')) {
-		curl_setopt(
-			$ch,
-			CURLOPT_HTTPHEADER,
-			['Accept: ' . $opts['accept_content']]
-		);
-	}
-
-	@curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
-	@curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
-
-	$range = intval(Config::get('system', 'curl_range_bytes', 0));
-
-	if ($range > 0) {
-		@curl_setopt($ch, CURLOPT_RANGE, '0-' . $range);
-	}
-
-	// Without this setting it seems as if some webservers send compressed content
-	// This seems to confuse curl so that it shows this uncompressed.
-	/// @todo  We could possibly set this value to "gzip" or something similar
-	curl_setopt($ch, CURLOPT_ENCODING, '');
-
-	if (x($opts, 'headers')) {
-		@curl_setopt($ch, CURLOPT_HTTPHEADER, $opts['headers']);
-	}
-
-	if (x($opts, 'nobody')) {
-		@curl_setopt($ch, CURLOPT_NOBODY, $opts['nobody']);
-	}
-
-	if (x($opts, 'timeout')) {
-		@curl_setopt($ch, CURLOPT_TIMEOUT, $opts['timeout']);
-	} else {
-		$curl_time = Config::get('system', 'curl_timeout', 60);
-		@curl_setopt($ch, CURLOPT_TIMEOUT, intval($curl_time));
-	}
-
-	// by default we will allow self-signed certs
-	// but you can override this
-
-	$check_cert = Config::get('system', 'verifyssl');
-	@curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, (($check_cert) ? true : false));
-
-	if ($check_cert) {
-		@curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
-	}
-
-	$proxy = Config::get('system', 'proxy');
-
-	if (strlen($proxy)) {
-		@curl_setopt($ch, CURLOPT_HTTPPROXYTUNNEL, 1);
-		@curl_setopt($ch, CURLOPT_PROXY, $proxy);
-		$proxyuser = @Config::get('system', 'proxyuser');
-
-		if (strlen($proxyuser)) {
-			@curl_setopt($ch, CURLOPT_PROXYUSERPWD, $proxyuser);
-		}
-	}
-
-	if (Config::get('system', 'ipv4_resolve', false)) {
-		curl_setopt($ch, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
-	}
-
-	if ($binary) {
-		@curl_setopt($ch, CURLOPT_BINARYTRANSFER, 1);
-	}
-
-	$a->set_curl_code(0);
-
-	// don't let curl abort the entire application
-	// if it throws any errors.
-
-	$s = @curl_exec($ch);
-	$curl_info = @curl_getinfo($ch);
-
-	// Special treatment for HTTP Code 416
-	// See https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/416
-	if (($curl_info['http_code'] == 416) && ($range > 0)) {
-		@curl_setopt($ch, CURLOPT_RANGE, '');
-		$s = @curl_exec($ch);
-		$curl_info = @curl_getinfo($ch);
-	}
-
-	if (curl_errno($ch) !== CURLE_OK) {
-		logger('fetch_url error fetching ' . $url . ': ' . curl_error($ch), LOGGER_NORMAL);
-	}
-
-	$ret['errno'] = curl_errno($ch);
-
-	$base = $s;
-	$ret['info'] = $curl_info;
-
-	$http_code = $curl_info['http_code'];
-
-	logger('fetch_url ' . $url . ': ' . $http_code . " " . $s, LOGGER_DATA);
-	$header = '';
-
-	// Pull out multiple headers, e.g. proxy and continuation headers
-	// allow for HTTP/2.x without fixing code
-
-	while (preg_match('/^HTTP\/[1-2].+? [1-5][0-9][0-9]/', $base)) {
-		$chunk = substr($base, 0, strpos($base, "\r\n\r\n") + 4);
-		$header .= $chunk;
-		$base = substr($base, strlen($chunk));
-	}
-
-	$a->set_curl_code($http_code);
-	$a->set_curl_content_type($curl_info['content_type']);
-	$a->set_curl_headers($header);
-
-	if ($http_code == 301 || $http_code == 302 || $http_code == 303 || $http_code == 307) {
-		$new_location_info = @parse_url($curl_info['redirect_url']);
-		$old_location_info = @parse_url($curl_info['url']);
-
-		$newurl = $curl_info['redirect_url'];
-
-		if (($new_location_info['path'] == '') && ( $new_location_info['host'] != '')) {
-			$newurl = $new_location_info['scheme'] . '://' . $new_location_info['host'] . $old_location_info['path'];
-		}
-
-		$matches = [];
-
-		if (preg_match('/(Location:|URI:)(.*?)\n/i', $header, $matches)) {
-			$newurl = trim(array_pop($matches));
-		}
-		if (strpos($newurl, '/') === 0) {
-			$newurl = $old_location_info["scheme"]."://".$old_location_info["host"].$newurl;
-		}
-
-		if (filter_var($newurl, FILTER_VALIDATE_URL)) {
-			$redirects++;
-			@curl_close($ch);
-			return z_fetch_url($newurl, $binary, $redirects, $opts);
-		}
-	}
-
-	$a->set_curl_code($http_code);
-	$a->set_curl_content_type($curl_info['content_type']);
-
-	$rc = intval($http_code);
-	$ret['return_code'] = $rc;
-	$ret['success'] = (($rc >= 200 && $rc <= 299) ? true : false);
-	$ret['redirect_url'] = $url;
-
-	if (!$ret['success']) {
-		$ret['error'] = curl_error($ch);
-		$ret['debug'] = $curl_info;
-		logger('z_fetch_url: error: '.$url.': '.$ret['return_code'].' - '.$ret['error'], LOGGER_DEBUG);
-		logger('z_fetch_url: debug: '.print_r($curl_info, true), LOGGER_DATA);
-	}
-
-	$ret['body'] = substr($s, strlen($header));
-	$ret['header'] = $header;
-
-	if (x($opts, 'debug')) {
-		$ret['debug'] = $curl_info;
-	}
-
-	@curl_close($ch);
-
-	$a->save_timestamp($stamp1, 'network');
-
-	return($ret);
+	return Network::zFetchURL($url, $binary, $redirects, $opts);
 }
 
-/**
- * @brief Send POST request to $url
- *
- * @param string  $url       URL to post
- * @param mixed   $params    array of POST variables
- * @param string  $headers   HTTP headers
- * @param integer $redirects Recursion counter for internal use - default = 0
- * @param integer $timeout   The timeout in seconds, default system config value or 60 seconds
- *
- * @return string The content
- */
 function post_url($url, $params, $headers = null, &$redirects = 0, $timeout = 0)
 {
-	$stamp1 = microtime(true);
-
-	if (blocked_url($url)) {
-		logger('post_url: domain of ' . $url . ' is blocked', LOGGER_DATA);
-		return false;
-	}
-
-	$a = get_app();
-	$ch = curl_init($url);
-
-	if (($redirects > 8) || (!$ch)) {
-		return false;
-	}
-
-	logger('post_url: start ' . $url, LOGGER_DATA);
-
-	curl_setopt($ch, CURLOPT_HEADER, true);
-	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
-	curl_setopt($ch, CURLOPT_POST, 1);
-	curl_setopt($ch, CURLOPT_POSTFIELDS, $params);
-	curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
-
-	if (Config::get('system', 'ipv4_resolve', false)) {
-		curl_setopt($ch, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
-	}
-
-	if (intval($timeout)) {
-		curl_setopt($ch, CURLOPT_TIMEOUT, $timeout);
-	} else {
-		$curl_time = Config::get('system', 'curl_timeout', 60);
-		curl_setopt($ch, CURLOPT_TIMEOUT, intval($curl_time));
-	}
-
-	if (defined('LIGHTTPD')) {
-		if (!is_array($headers)) {
-			$headers = ['Expect:'];
-		} else {
-			if (!in_array('Expect:', $headers)) {
-				array_push($headers, 'Expect:');
-			}
-		}
-	}
-
-	if ($headers) {
-		curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
-	}
-
-	$check_cert = Config::get('system', 'verifyssl');
-	curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, (($check_cert) ? true : false));
-
-	if ($check_cert) {
-		@curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
-	}
-
-	$proxy = Config::get('system', 'proxy');
-
-	if (strlen($proxy)) {
-		curl_setopt($ch, CURLOPT_HTTPPROXYTUNNEL, 1);
-		curl_setopt($ch, CURLOPT_PROXY, $proxy);
-		$proxyuser = Config::get('system', 'proxyuser');
-		if (strlen($proxyuser)) {
-			curl_setopt($ch, CURLOPT_PROXYUSERPWD, $proxyuser);
-		}
-	}
-
-	$a->set_curl_code(0);
-
-	// don't let curl abort the entire application
-	// if it throws any errors.
-
-	$s = @curl_exec($ch);
-
-	$base = $s;
-	$curl_info = curl_getinfo($ch);
-	$http_code = $curl_info['http_code'];
-
-	logger('post_url: result ' . $http_code . ' - ' . $url, LOGGER_DATA);
-
-	$header = '';
-
-	// Pull out multiple headers, e.g. proxy and continuation headers
-	// allow for HTTP/2.x without fixing code
-
-	while (preg_match('/^HTTP\/[1-2].+? [1-5][0-9][0-9]/', $base)) {
-		$chunk = substr($base, 0, strpos($base, "\r\n\r\n") + 4);
-		$header .= $chunk;
-		$base = substr($base, strlen($chunk));
-	}
-
-	if ($http_code == 301 || $http_code == 302 || $http_code == 303 || $http_code == 307) {
-		$matches = [];
-		preg_match('/(Location:|URI:)(.*?)\n/', $header, $matches);
-		$newurl = trim(array_pop($matches));
-
-		if (strpos($newurl, '/') === 0) {
-			$newurl = $old_location_info["scheme"] . "://" . $old_location_info["host"] . $newurl;
-		}
-
-		if (filter_var($newurl, FILTER_VALIDATE_URL)) {
-			$redirects++;
-			logger('post_url: redirect ' . $url . ' to ' . $newurl);
-			return post_url($newurl, $params, $headers, $redirects, $timeout);
-		}
-	}
-
-	$a->set_curl_code($http_code);
-
-	$body = substr($s, strlen($header));
-
-	$a->set_curl_headers($header);
-
-	curl_close($ch);
-
-	$a->save_timestamp($stamp1, 'network');
-
-	logger('post_url: end ' . $url, LOGGER_DATA);
-
-	return $body;
+	return Network::postURL($url, $params, $headers, $redirects, $timeout);
 }
 
-// Generic XML return
-// Outputs a basic dfrn XML status structure to STDOUT, with a <status> variable
-// of $st and an optional text <message> of $message and terminates the current process.
-
 function xml_status($st, $message = '')
 {
-	$result = ['status' => $st];
-
-	if ($message != '') {
-		$result['message'] = $message;
-	}
-
-	if ($st) {
-		logger('xml_status returning non_zero: ' . $st . " message=" . $message);
-	}
-
-	header("Content-type: text/xml");
-
-	$xmldata = ["result" => $result];
-
-	echo XML::fromArray($xmldata, $xml);
-
-	killme();
+	Network::xmlStatus($st, $message);
 }
 
-/**
- * @brief Send HTTP status header and exit.
- *
- * @param integer $val HTTP status result value
- * @param array $description optional message
- *    'title' => header title
- *    'description' => optional message
- */
-
-/**
- * @brief Send HTTP status header and exit.
- *
- * @param integer $val         HTTP status result value
- * @param array   $description optional message
- *                             'title' => header title
- *                             'description' => optional message
- */
 function http_status_exit($val, $description = [])
 {
-	$err = '';
-	if ($val >= 400) {
-		$err = 'Error';
-		if (!isset($description["title"])) {
-			$description["title"] = $err." ".$val;
-		}
-	}
-	if ($val >= 200 && $val < 300)
-		$err = 'OK';
-
-	logger('http_status_exit ' . $val);
-	header($_SERVER["SERVER_PROTOCOL"] . ' ' . $val . ' ' . $err);
-
-	if (isset($description["title"])) {
-		$tpl = get_markup_template('http_status.tpl');
-		echo replace_macros(
-			$tpl,
-			[
-				'$title' => $description["title"],
-				'$description' => $description["description"]]
-		);
-	}
-
-	killme();
+	Network::httpStatusExit($val, $description);
 }
 
-/**
- * @brief Check URL to se if ts's real
- *
- * Take a URL from the wild, prepend http:// if necessary
- * and check DNS to see if it's real (or check if is a valid IP address)
- *
- * @param string $url The URL to be validated
- * @return string|boolean The actual working URL, false else
- */
 function validate_url($url)
 {
-	if (Config::get('system', 'disable_url_validation')) {
-		return $url;
-	}
-
-	// no naked subdomains (allow localhost for tests)
-	if (strpos($url, '.') === false && strpos($url, '/localhost/') === false) {
-		return false;
-	}
-
-	if (substr($url, 0, 4) != 'http') {
-		$url = 'http://' . $url;
-	}
-
-	/// @TODO Really suppress function outcomes? Why not find them + debug them?
-	$h = @parse_url($url);
-
-	if ((is_array($h)) && (@dns_get_record($h['host'], DNS_A + DNS_CNAME + DNS_PTR) || filter_var($h['host'], FILTER_VALIDATE_IP) )) {
-		return $url;
-	}
-
-	return false;
+	return Network::validateURL($url);
 }
 
-/**
- * @brief Checks that email is an actual resolvable internet address
- *
- * @param string $addr The email address
- * @return boolean True if it's a valid email address, false if it's not
- */
 function validate_email($addr)
 {
-	if (Config::get('system', 'disable_email_validation')) {
-		return true;
-	}
-
-	if (! strpos($addr, '@')) {
-		return false;
-	}
-
-	$h = substr($addr, strpos($addr, '@') + 1);
-
-	if (($h) && (dns_get_record($h, DNS_A + DNS_CNAME + DNS_PTR + DNS_MX) || filter_var($h, FILTER_VALIDATE_IP) )) {
-		return true;
-	}
-	return false;
+	return Network::validateEmail($addr);
 }
 
-/**
- * @brief Check if URL is allowed
- *
- * Check $url against our list of allowed sites,
- * wildcards allowed. If allowed_sites is unset return true;
- *
- * @param string $url URL which get tested
- * @return boolean True if url is allowed otherwise return false
- */
 function allowed_url($url)
 {
-	$h = @parse_url($url);
-
-	if (! $h) {
-		return false;
-	}
-
-	$str_allowed = Config::get('system', 'allowed_sites');
-	if (! $str_allowed) {
-		return true;
-	}
-
-	$found = false;
-
-	$host = strtolower($h['host']);
-
-	// always allow our own site
-	if ($host == strtolower($_SERVER['SERVER_NAME'])) {
-		return true;
-	}
-
-	$fnmatch = function_exists('fnmatch');
-	$allowed = explode(',', $str_allowed);
-
-	if (count($allowed)) {
-		foreach ($allowed as $a) {
-			$pat = strtolower(trim($a));
-			if (($fnmatch && fnmatch($pat, $host)) || ($pat == $host)) {
-				$found = true;
-				break;
-			}
-		}
-	}
-	return $found;
+	return Network::allowedURL($url);
 }
 
-/**
- * Checks if the provided url domain is on the domain blocklist.
- * Returns true if it is or malformed URL, false if not.
- *
- * @param string $url The url to check the domain from
- *
- * @return boolean
- */
 function blocked_url($url)
 {
-	$h = @parse_url($url);
-
-	if (! $h) {
-		return true;
-	}
-
-	$domain_blocklist = Config::get('system', 'blocklist', []);
-	if (! $domain_blocklist) {
-		return false;
-	}
-
-	$host = strtolower($h['host']);
-
-	foreach ($domain_blocklist as $domain_block) {
-		if (strtolower($domain_block['domain']) == $host) {
-			return true;
-		}
-	}
-
-	return false;
+	return Network::blockedURL($url);
 }
 
-/**
- * @brief Check if email address is allowed to register here.
- *
- * Compare against our list (wildcards allowed).
- *
- * @param  string $email email address
- * @return boolean False if not allowed, true if allowed
- *    or if allowed list is not configured
- */
-function allowed_email($email)
+function allowedEmail($email)
 {
-	$domain = strtolower(substr($email, strpos($email, '@') + 1));
-	if (!$domain) {
-		return false;
-	}
-
-	$str_allowed = Config::get('system', 'allowed_email', '');
-	if (!x($str_allowed)) {
-		return true;
-	}
-
-	$allowed = explode(',', $str_allowed);
-
-	return allowed_domain($domain, $allowed);
+	return Network::allowedEmail($email);
 }
 
-/**
- * Checks for the existence of a domain in a domain list
- *
- * @brief Checks for the existence of a domain in a domain list
- * @param string $domain
- * @param array  $domain_list
- * @return boolean
- */
 function allowed_domain($domain, array $domain_list)
 {
-	$found = false;
-
-	foreach ($domain_list as $item) {
-		$pat = strtolower(trim($item));
-		if (fnmatch($pat, $domain) || ($pat == $domain)) {
-			$found = true;
-			break;
-		}
-	}
-
-	return $found;
+	return Network::allowedDomain($domain, $domain_list);
 }
 
 function avatar_img($email)
 {
-	$avatar['size'] = 175;
-	$avatar['email'] = $email;
-	$avatar['url'] = '';
-	$avatar['success'] = false;
-
-	Addon::callHooks('avatar_lookup', $avatar);
-
-	if (! $avatar['success']) {
-		$avatar['url'] = System::baseUrl() . '/images/person-175.jpg';
-	}
-
-	logger('Avatar: ' . $avatar['email'] . ' ' . $avatar['url'], LOGGER_DEBUG);
-	return $avatar['url'];
+	return Network::avatarImg($email);
 }
 
 
 function parse_xml_string($s, $strict = true)
 {
-	// the "strict" parameter is deactivated
-
-	/// @todo Move this function to the xml class
-	libxml_use_internal_errors(true);
-
-	$x = @simplexml_load_string($s);
-	if (!$x) {
-		logger('libxml: parse: error: ' . $s, LOGGER_DATA);
-		foreach (libxml_get_errors() as $err) {
-			logger('libxml: parse: ' . $err->code." at ".$err->line.":".$err->column." : ".$err->message, LOGGER_DATA);
-		}
-		libxml_clear_errors();
-	}
-	return $x;
+	return Network::parseXmlString($s, $strict);
 }
 
 function scale_external_images($srctext, $include_link = true, $scale_replace = false)
 {
-	// Suppress "view full size"
-	if (intval(Config::get('system', 'no_view_full_size'))) {
-		$include_link = false;
-	}
-
-	// Picture addresses can contain special characters
-	$s = htmlspecialchars_decode($srctext);
-
-	$matches = null;
-	$c = preg_match_all('/\[img.*?\](.*?)\[\/img\]/ism', $s, $matches, PREG_SET_ORDER);
-	if ($c) {
-		foreach ($matches as $mtch) {
-			logger('scale_external_image: ' . $mtch[1]);
-
-			$hostname = str_replace('www.', '', substr(System::baseUrl(), strpos(System::baseUrl(), '://') + 3));
-			if (stristr($mtch[1], $hostname)) {
-				continue;
-			}
-
-			// $scale_replace, if passed, is an array of two elements. The
-			// first is the name of the full-size image. The second is the
-			// name of a remote, scaled-down version of the full size image.
-			// This allows Friendica to display the smaller remote image if
-			// one exists, while still linking to the full-size image
-			if ($scale_replace) {
-				$scaled = str_replace($scale_replace[0], $scale_replace[1], $mtch[1]);
-			} else {
-				$scaled = $mtch[1];
-			}
-			$i = fetch_url($scaled);
-			if (! $i) {
-				return $srctext;
-			}
-
-			// guess mimetype from headers or filename
-			$type = Image::guessType($mtch[1], true);
-
-			if ($i) {
-				$Image = new Image($i, $type);
-				if ($Image->isValid()) {
-					$orig_width = $Image->getWidth();
-					$orig_height = $Image->getHeight();
-
-					if ($orig_width > 640 || $orig_height > 640) {
-						$Image->scaleDown(640);
-						$new_width = $Image->getWidth();
-						$new_height = $Image->getHeight();
-						logger('scale_external_images: ' . $orig_width . '->' . $new_width . 'w ' . $orig_height . '->' . $new_height . 'h' . ' match: ' . $mtch[0], LOGGER_DEBUG);
-						$s = str_replace(
-							$mtch[0],
-							'[img=' . $new_width . 'x' . $new_height. ']' . $scaled . '[/img]'
-							. "\n" . (($include_link)
-								? '[url=' . $mtch[1] . ']' . L10n::t('view full size') . '[/url]' . "\n"
-								: ''),
-							$s
-						);
-						logger('scale_external_images: new string: ' . $s, LOGGER_DEBUG);
-					}
-				}
-			}
-		}
-	}
-
-	// replace the special char encoding
-	$s = htmlspecialchars($s, ENT_NOQUOTES, 'UTF-8');
-	return $s;
+	return Network::scaleExternalImages($srctext, $include_link, $scale_replace);
 }
 
-
 function fix_contact_ssl_policy(&$contact, $new_policy)
 {
-	$ssl_changed = false;
-	if ((intval($new_policy) == SSL_POLICY_SELFSIGN || $new_policy === 'self') && strstr($contact['url'], 'https:')) {
-		$ssl_changed = true;
-		$contact['url']     = 	str_replace('https:', 'http:', $contact['url']);
-		$contact['request'] = 	str_replace('https:', 'http:', $contact['request']);
-		$contact['notify']  = 	str_replace('https:', 'http:', $contact['notify']);
-		$contact['poll']    = 	str_replace('https:', 'http:', $contact['poll']);
-		$contact['confirm'] = 	str_replace('https:', 'http:', $contact['confirm']);
-		$contact['poco']    = 	str_replace('https:', 'http:', $contact['poco']);
-	}
-
-	if ((intval($new_policy) == SSL_POLICY_FULL || $new_policy === 'full') && strstr($contact['url'], 'http:')) {
-		$ssl_changed = true;
-		$contact['url']     = 	str_replace('http:', 'https:', $contact['url']);
-		$contact['request'] = 	str_replace('http:', 'https:', $contact['request']);
-		$contact['notify']  = 	str_replace('http:', 'https:', $contact['notify']);
-		$contact['poll']    = 	str_replace('http:', 'https:', $contact['poll']);
-		$contact['confirm'] = 	str_replace('http:', 'https:', $contact['confirm']);
-		$contact['poco']    = 	str_replace('http:', 'https:', $contact['poco']);
-	}
-
-	if ($ssl_changed) {
-		$fields = ['url' => $contact['url'], 'request' => $contact['request'],
-				'notify' => $contact['notify'], 'poll' => $contact['poll'],
-				'confirm' => $contact['confirm'], 'poco' => $contact['poco']];
-		dba::update('contact', $fields, ['id' => $contact['id']]);
-	}
+	Network::fixContactSslPolicy($contact, $new_policy);
 }
 
-/**
- * @brief Remove Google Analytics and other tracking platforms params from URL
- *
- * @param string $url Any user-submitted URL that may contain tracking params
- * @return string The same URL stripped of tracking parameters
- */
 function strip_tracking_query_params($url)
 {
-	$urldata = parse_url($url);
-	if (is_string($urldata["query"])) {
-		$query = $urldata["query"];
-		parse_str($query, $querydata);
-
-		if (is_array($querydata)) {
-			foreach ($querydata as $param => $value) {
-				if (in_array(
-					$param,
-					[
-						"utm_source", "utm_medium", "utm_term", "utm_content", "utm_campaign",
-						"wt_mc", "pk_campaign", "pk_kwd", "mc_cid", "mc_eid",
-						"fb_action_ids", "fb_action_types", "fb_ref",
-						"awesm", "wtrid",
-						"woo_campaign", "woo_source", "woo_medium", "woo_content", "woo_term"]
-					)
-				) {
-					$pair = $param . "=" . urlencode($value);
-					$url = str_replace($pair, "", $url);
-
-					// Second try: if the url isn't encoded completely
-					$pair = $param . "=" . str_replace(" ", "+", $value);
-					$url = str_replace($pair, "", $url);
-
-					// Third try: Maybey the url isn't encoded at all
-					$pair = $param . "=" . $value;
-					$url = str_replace($pair, "", $url);
-
-					$url = str_replace(["?&", "&&"], ["?", ""], $url);
-				}
-			}
-		}
-
-		if (substr($url, -1, 1) == "?") {
-			$url = substr($url, 0, -1);
-		}
-	}
-
-	return $url;
+	return Network::stripTrackingQueryParams($url);
 }
 
-/**
- * @brief Returns the original URL of the provided URL
- *
- * This function strips tracking query params and follows redirections, either
- * through HTTP code or meta refresh tags. Stops after 10 redirections.
- *
- * @todo Remove the $fetchbody parameter that generates an extraneous HEAD request
- *
- * @see ParseUrl::getSiteinfo
- *
- * @param string $url       A user-submitted URL
- * @param int    $depth     The current redirection recursion level (internal)
- * @param bool   $fetchbody Wether to fetch the body or not after the HEAD requests
- * @return string A canonical URL
- */
 function original_url($url, $depth = 1, $fetchbody = false)
 {
-	$a = get_app();
-
-	$url = strip_tracking_query_params($url);
-
-	if ($depth > 10) {
-		return($url);
-	}
-
-	$url = trim($url, "'");
-
-	$stamp1 = microtime(true);
-
-	$ch = curl_init();
-	curl_setopt($ch, CURLOPT_URL, $url);
-	curl_setopt($ch, CURLOPT_HEADER, 1);
-	curl_setopt($ch, CURLOPT_NOBODY, 1);
-	curl_setopt($ch, CURLOPT_TIMEOUT, 10);
-	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
-	curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
-
-	curl_exec($ch);
-	$curl_info = @curl_getinfo($ch);
-	$http_code = $curl_info['http_code'];
-	curl_close($ch);
-
-	$a->save_timestamp($stamp1, "network");
-
-	if ($http_code == 0)
-		return($url);
-
-	if ((($curl_info['http_code'] == "301") || ($curl_info['http_code'] == "302"))
-		&& (($curl_info['redirect_url'] != "") || ($curl_info['location'] != ""))
-	) {
-		if ($curl_info['redirect_url'] != "") {
-			return(original_url($curl_info['redirect_url'], ++$depth, $fetchbody));
-		} else {
-			return(original_url($curl_info['location'], ++$depth, $fetchbody));
-		}
-	}
-
-	// Check for redirects in the meta elements of the body if there are no redirects in the header.
-	if (!$fetchbody) {
-		return(original_url($url, ++$depth, true));
-	}
-
-	// if the file is too large then exit
-	if ($curl_info["download_content_length"] > 1000000) {
-		return($url);
-	}
-
-	// if it isn't a HTML file then exit
-	if (($curl_info["content_type"] != "") && !strstr(strtolower($curl_info["content_type"]), "html")) {
-		return($url);
-	}
-
-	$stamp1 = microtime(true);
-
-	$ch = curl_init();
-	curl_setopt($ch, CURLOPT_URL, $url);
-	curl_setopt($ch, CURLOPT_HEADER, 0);
-	curl_setopt($ch, CURLOPT_NOBODY, 0);
-	curl_setopt($ch, CURLOPT_TIMEOUT, 10);
-	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
-	curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
-
-	$body = curl_exec($ch);
-	curl_close($ch);
-
-	$a->save_timestamp($stamp1, "network");
-
-	if (trim($body) == "") {
-		return($url);
-	}
-
-	// Check for redirect in meta elements
-	$doc = new DOMDocument();
-	@$doc->loadHTML($body);
-
-	$xpath = new DomXPath($doc);
-
-	$list = $xpath->query("//meta[@content]");
-	foreach ($list as $node) {
-		$attr = [];
-		if ($node->attributes->length) {
-			foreach ($node->attributes as $attribute) {
-				$attr[$attribute->name] = $attribute->value;
-			}
-		}
-
-		if (@$attr["http-equiv"] == 'refresh') {
-			$path = $attr["content"];
-			$pathinfo = explode(";", $path);
-			foreach ($pathinfo as $value) {
-				if (substr(strtolower($value), 0, 4) == "url=") {
-					return(original_url(substr($value, 4), ++$depth));
-				}
-			}
-		}
-	}
-
-	return $url;
+	return Network::originalURL($url, $depth, $fetchbody);
 }
 
 function short_link($url)
 {
-	require_once 'library/slinky.php';
-	$slinky = new Slinky($url);
-	$yourls_url = Config::get('yourls', 'url1');
-	if ($yourls_url) {
-		$yourls_username = Config::get('yourls', 'username1');
-		$yourls_password = Config::get('yourls', 'password1');
-		$yourls_ssl = Config::get('yourls', 'ssl1');
-		$yourls = new Slinky_YourLS();
-		$yourls->set('username', $yourls_username);
-		$yourls->set('password', $yourls_password);
-		$yourls->set('ssl', $yourls_ssl);
-		$yourls->set('yourls-url', $yourls_url);
-		$slinky->set_cascade([$yourls, new Slinky_Ur1ca(), new Slinky_TinyURL()]);
-	} else {
-		// setup a cascade of shortening services
-		// try to get a short link from these services
-		// in the order ur1.ca, tinyurl
-		$slinky->set_cascade([new Slinky_Ur1ca(), new Slinky_TinyURL()]);
-	}
-	return $slinky->short();
+	return Network::shortLink($url);
 }
 
-/**
- * @brief Encodes content to json
- *
- * This function encodes an array to json format
- * and adds an application/json HTTP header to the output.
- * After finishing the process is getting killed.
- *
- * @param array $x The input content
- */
 function json_return_and_die($x)
 {
-	header("content-type: application/json");
-	echo json_encode($x);
-	killme();
+	Network::jsonReturnAndDie($x);
 }
 
-/**
- * @brief Find the matching part between two url
- *
- * @param string $url1
- * @param string $url2
- * @return string The matching part
- */
 function matching_url($url1, $url2)
 {
-	if (($url1 == "") || ($url2 == "")) {
-		return "";
-	}
-
-	$url1 = normalise_link($url1);
-	$url2 = normalise_link($url2);
-
-	$parts1 = parse_url($url1);
-	$parts2 = parse_url($url2);
-
-	if (!isset($parts1["host"]) || !isset($parts2["host"])) {
-		return "";
-	}
-
-	if ($parts1["scheme"] != $parts2["scheme"]) {
-		return "";
-	}
-
-	if ($parts1["host"] != $parts2["host"]) {
-		return "";
-	}
-
-	if ($parts1["port"] != $parts2["port"]) {
-		return "";
-	}
-
-	$match = $parts1["scheme"]."://".$parts1["host"];
-
-	if ($parts1["port"]) {
-		$match .= ":".$parts1["port"];
-	}
-
-	$pathparts1 = explode("/", $parts1["path"]);
-	$pathparts2 = explode("/", $parts2["path"]);
-
-	$i = 0;
-	$path = "";
-	do {
-		$path1 = $pathparts1[$i];
-		$path2 = $pathparts2[$i];
-
-		if ($path1 == $path2) {
-			$path .= $path1."/";
-		}
-	} while (($path1 == $path2) && ($i++ <= count($pathparts1)));
-
-	$match .= $path;
-
-	return normalise_link($match);
+	return Network::matchingURL($url1, $url2);
 }
 
-/**
- * @brief Glue url parts together
- *
- * @param array $parsed URL parts
- *
- * @return string The glued URL
- */
 function unParseUrl($parsed)
 {
-	$get = function ($key) use ($parsed) {
-		return isset($parsed[$key]) ? $parsed[$key] : null;
-	};
-
-	$pass      = $get('pass');
-	$user      = $get('user');
-	$userinfo  = $pass !== null ? "$user:$pass" : $user;
-	$port      = $get('port');
-	$scheme    = $get('scheme');
-	$query     = $get('query');
-	$fragment  = $get('fragment');
-	$authority = ($userinfo !== null ? $userinfo."@" : '') .
-					$get('host') .
-					($port ? ":$port" : '');
-
-	return	(strlen($scheme) ? $scheme.":" : '') .
-		(strlen($authority) ? "//".$authority : '') .
-		$get('path') .
-		(strlen($query) ? "?".$query : '') .
-		(strlen($fragment) ? "#".$fragment : '');
+	return Network::unParseURL($parsed);
 }
diff --git a/src/Util/Network.php b/src/Util/Network.php
new file mode 100644
index 000000000..f25d9c9a2
--- /dev/null
+++ b/src/Util/Network.php
@@ -0,0 +1,1086 @@
+<?php
+/**
+ * @file src/Util/Network.php
+ */
+namespace Friendica\Util;
+
+use Friendica\App;
+use Friendica\Core\Addon;
+use Friendica\Core\L10n;
+use Friendica\Core\System;
+use Friendica\Core\Config;
+use Friendica\Network\Probe;
+use Friendica\Object\Image;
+use Friendica\Util\XML;
+
+require_once 'library/slinky.php';
+
+class Network
+{
+	/**
+	 * @brief Curl wrapper
+	 *
+	 * If binary flag is true, return binary results.
+	 * Set the cookiejar argument to a string (e.g. "/tmp/friendica-cookies.txt")
+	 * to preserve cookies from one request to the next.
+	 *
+	 * @param string  $url            URL to fetch
+	 * @param boolean $binary         default false
+	 *                                TRUE if asked to return binary results (file download)
+	 * @param integer $redirects      The recursion counter for internal use - default 0
+	 * @param integer $timeout        Timeout in seconds, default system config value or 60 seconds
+	 * @param string  $accept_content supply Accept: header with 'accept_content' as the value
+	 * @param string  $cookiejar      Path to cookie jar file
+	 *
+	 * @return string The fetched content
+	 */
+	public static function fetchURL($url, $binary = false, &$redirects = 0, $timeout = 0, $accept_content = null, $cookiejar = 0)
+	{
+		$ret = self::zFetchURL(
+			$url,
+			$binary,
+			$redirects,
+			['timeout'=>$timeout,
+			'accept_content'=>$accept_content,
+			'cookiejar'=>$cookiejar
+			]
+		);
+
+		return($ret['body']);
+	}
+
+	/**
+	 * @brief fetches an URL.
+	 *
+	 * @param string  $url       URL to fetch
+	 * @param boolean $binary    default false
+	 *                           TRUE if asked to return binary results (file download)
+	 * @param int     $redirects The recursion counter for internal use - default 0
+	 * @param array   $opts      (optional parameters) assoziative array with:
+	 *                           'accept_content' => supply Accept: header with 'accept_content' as the value
+	 *                           'timeout' => int Timeout in seconds, default system config value or 60 seconds
+	 *                           'http_auth' => username:password
+	 *                           'novalidate' => do not validate SSL certs, default is to validate using our CA list
+	 *                           'nobody' => only return the header
+	 *                           'cookiejar' => path to cookie jar file
+	 *
+	 * @return array an assoziative array with:
+	 *    int 'return_code' => HTTP return code or 0 if timeout or failure
+	 *    boolean 'success' => boolean true (if HTTP 2xx result) or false
+	 *    string 'redirect_url' => in case of redirect, content was finally retrieved from this URL
+	 *    string 'header' => HTTP headers
+	 *    string 'body' => fetched content
+	 */
+	public static function zFetchURL($url, $binary = false, &$redirects = 0, $opts = [])
+	{
+		$ret = ['return_code' => 0, 'success' => false, 'header' => '', 'info' => '', 'body' => ''];
+
+		$stamp1 = microtime(true);
+
+		$a = get_app();
+
+		if (blocked_url($url)) {
+			logger('z_fetch_url: domain of ' . $url . ' is blocked', LOGGER_DATA);
+			return $ret;
+		}
+
+		$ch = @curl_init($url);
+
+		if (($redirects > 8) || (!$ch)) {
+			return $ret;
+		}
+
+		@curl_setopt($ch, CURLOPT_HEADER, true);
+
+		if (x($opts, "cookiejar")) {
+			curl_setopt($ch, CURLOPT_COOKIEJAR, $opts["cookiejar"]);
+			curl_setopt($ch, CURLOPT_COOKIEFILE, $opts["cookiejar"]);
+		}
+
+		// These settings aren't needed. We're following the location already.
+		//	@curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
+		//	@curl_setopt($ch, CURLOPT_MAXREDIRS, 5);
+
+		if (x($opts, 'accept_content')) {
+			curl_setopt(
+				$ch,
+				CURLOPT_HTTPHEADER,
+				['Accept: ' . $opts['accept_content']]
+			);
+		}
+
+		@curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
+		@curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
+
+		$range = intval(Config::get('system', 'curl_range_bytes', 0));
+
+		if ($range > 0) {
+			@curl_setopt($ch, CURLOPT_RANGE, '0-' . $range);
+		}
+
+		// Without this setting it seems as if some webservers send compressed content
+		// This seems to confuse curl so that it shows this uncompressed.
+		/// @todo  We could possibly set this value to "gzip" or something similar
+		curl_setopt($ch, CURLOPT_ENCODING, '');
+
+		if (x($opts, 'headers')) {
+			@curl_setopt($ch, CURLOPT_HTTPHEADER, $opts['headers']);
+		}
+
+		if (x($opts, 'nobody')) {
+			@curl_setopt($ch, CURLOPT_NOBODY, $opts['nobody']);
+		}
+
+		if (x($opts, 'timeout')) {
+			@curl_setopt($ch, CURLOPT_TIMEOUT, $opts['timeout']);
+		} else {
+			$curl_time = Config::get('system', 'curl_timeout', 60);
+			@curl_setopt($ch, CURLOPT_TIMEOUT, intval($curl_time));
+		}
+
+		// by default we will allow self-signed certs
+		// but you can override this
+
+		$check_cert = Config::get('system', 'verifyssl');
+		@curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, (($check_cert) ? true : false));
+
+		if ($check_cert) {
+			@curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
+		}
+
+		$proxy = Config::get('system', 'proxy');
+
+		if (strlen($proxy)) {
+			@curl_setopt($ch, CURLOPT_HTTPPROXYTUNNEL, 1);
+			@curl_setopt($ch, CURLOPT_PROXY, $proxy);
+			$proxyuser = @Config::get('system', 'proxyuser');
+
+			if (strlen($proxyuser)) {
+				@curl_setopt($ch, CURLOPT_PROXYUSERPWD, $proxyuser);
+			}
+		}
+
+		if (Config::get('system', 'ipv4_resolve', false)) {
+			curl_setopt($ch, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
+		}
+
+		if ($binary) {
+			@curl_setopt($ch, CURLOPT_BINARYTRANSFER, 1);
+		}
+
+		$a->set_curl_code(0);
+
+		// don't let curl abort the entire application
+		// if it throws any errors.
+
+		$s = @curl_exec($ch);
+		$curl_info = @curl_getinfo($ch);
+
+		// Special treatment for HTTP Code 416
+		// See https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/416
+		if (($curl_info['http_code'] == 416) && ($range > 0)) {
+			@curl_setopt($ch, CURLOPT_RANGE, '');
+			$s = @curl_exec($ch);
+			$curl_info = @curl_getinfo($ch);
+		}
+
+		if (curl_errno($ch) !== CURLE_OK) {
+			logger('fetch_url error fetching ' . $url . ': ' . curl_error($ch), LOGGER_NORMAL);
+		}
+
+		$ret['errno'] = curl_errno($ch);
+
+		$base = $s;
+		$ret['info'] = $curl_info;
+
+		$http_code = $curl_info['http_code'];
+
+		logger('fetch_url ' . $url . ': ' . $http_code . " " . $s, LOGGER_DATA);
+		$header = '';
+
+		// Pull out multiple headers, e.g. proxy and continuation headers
+		// allow for HTTP/2.x without fixing code
+
+		while (preg_match('/^HTTP\/[1-2].+? [1-5][0-9][0-9]/', $base)) {
+			$chunk = substr($base, 0, strpos($base, "\r\n\r\n") + 4);
+			$header .= $chunk;
+			$base = substr($base, strlen($chunk));
+		}
+
+		$a->set_curl_code($http_code);
+		$a->set_curl_content_type($curl_info['content_type']);
+		$a->set_curl_headers($header);
+
+		if ($http_code == 301 || $http_code == 302 || $http_code == 303 || $http_code == 307) {
+			$new_location_info = @parse_url($curl_info['redirect_url']);
+			$old_location_info = @parse_url($curl_info['url']);
+
+			$newurl = $curl_info['redirect_url'];
+
+			if (($new_location_info['path'] == '') && ( $new_location_info['host'] != '')) {
+				$newurl = $new_location_info['scheme'] . '://' . $new_location_info['host'] . $old_location_info['path'];
+			}
+
+			$matches = [];
+
+			if (preg_match('/(Location:|URI:)(.*?)\n/i', $header, $matches)) {
+				$newurl = trim(array_pop($matches));
+			}
+			if (strpos($newurl, '/') === 0) {
+				$newurl = $old_location_info["scheme"]."://".$old_location_info["host"].$newurl;
+			}
+
+			if (filter_var($newurl, FILTER_VALIDATE_URL)) {
+				$redirects++;
+				@curl_close($ch);
+				return z_fetch_url($newurl, $binary, $redirects, $opts);
+			}
+		}
+
+		$a->set_curl_code($http_code);
+		$a->set_curl_content_type($curl_info['content_type']);
+
+		$rc = intval($http_code);
+		$ret['return_code'] = $rc;
+		$ret['success'] = (($rc >= 200 && $rc <= 299) ? true : false);
+		$ret['redirect_url'] = $url;
+
+		if (!$ret['success']) {
+			$ret['error'] = curl_error($ch);
+			$ret['debug'] = $curl_info;
+			logger('z_fetch_url: error: '.$url.': '.$ret['return_code'].' - '.$ret['error'], LOGGER_DEBUG);
+			logger('z_fetch_url: debug: '.print_r($curl_info, true), LOGGER_DATA);
+		}
+
+		$ret['body'] = substr($s, strlen($header));
+		$ret['header'] = $header;
+
+		if (x($opts, 'debug')) {
+			$ret['debug'] = $curl_info;
+		}
+
+		@curl_close($ch);
+
+		$a->save_timestamp($stamp1, 'network');
+
+		return($ret);
+	}
+
+	/**
+	 * @brief Send POST request to $url
+	 *
+	 * @param string  $url       URL to post
+	 * @param mixed   $params    array of POST variables
+	 * @param string  $headers   HTTP headers
+	 * @param integer $redirects Recursion counter for internal use - default = 0
+	 * @param integer $timeout   The timeout in seconds, default system config value or 60 seconds
+	 *
+	 * @return string The content
+	 */
+	public static function postURL($url, $params, $headers = null, &$redirects = 0, $timeout = 0)
+	{
+		$stamp1 = microtime(true);
+
+		if (blocked_url($url)) {
+			logger('post_url: domain of ' . $url . ' is blocked', LOGGER_DATA);
+			return false;
+		}
+
+		$a = get_app();
+		$ch = curl_init($url);
+
+		if (($redirects > 8) || (!$ch)) {
+			return false;
+		}
+
+		logger('post_url: start ' . $url, LOGGER_DATA);
+
+		curl_setopt($ch, CURLOPT_HEADER, true);
+		curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
+		curl_setopt($ch, CURLOPT_POST, 1);
+		curl_setopt($ch, CURLOPT_POSTFIELDS, $params);
+		curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
+
+		if (Config::get('system', 'ipv4_resolve', false)) {
+			curl_setopt($ch, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
+		}
+
+		if (intval($timeout)) {
+			curl_setopt($ch, CURLOPT_TIMEOUT, $timeout);
+		} else {
+			$curl_time = Config::get('system', 'curl_timeout', 60);
+			curl_setopt($ch, CURLOPT_TIMEOUT, intval($curl_time));
+		}
+
+		if (defined('LIGHTTPD')) {
+			if (!is_array($headers)) {
+				$headers = ['Expect:'];
+			} else {
+				if (!in_array('Expect:', $headers)) {
+					array_push($headers, 'Expect:');
+				}
+			}
+		}
+
+		if ($headers) {
+			curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
+		}
+
+		$check_cert = Config::get('system', 'verifyssl');
+		curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, (($check_cert) ? true : false));
+
+		if ($check_cert) {
+			@curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
+		}
+
+		$proxy = Config::get('system', 'proxy');
+
+		if (strlen($proxy)) {
+			curl_setopt($ch, CURLOPT_HTTPPROXYTUNNEL, 1);
+			curl_setopt($ch, CURLOPT_PROXY, $proxy);
+			$proxyuser = Config::get('system', 'proxyuser');
+			if (strlen($proxyuser)) {
+				curl_setopt($ch, CURLOPT_PROXYUSERPWD, $proxyuser);
+			}
+		}
+
+		$a->set_curl_code(0);
+
+		// don't let curl abort the entire application
+		// if it throws any errors.
+
+		$s = @curl_exec($ch);
+
+		$base = $s;
+		$curl_info = curl_getinfo($ch);
+		$http_code = $curl_info['http_code'];
+
+		logger('post_url: result ' . $http_code . ' - ' . $url, LOGGER_DATA);
+
+		$header = '';
+
+		// Pull out multiple headers, e.g. proxy and continuation headers
+		// allow for HTTP/2.x without fixing code
+
+		while (preg_match('/^HTTP\/[1-2].+? [1-5][0-9][0-9]/', $base)) {
+			$chunk = substr($base, 0, strpos($base, "\r\n\r\n") + 4);
+			$header .= $chunk;
+			$base = substr($base, strlen($chunk));
+		}
+
+		if ($http_code == 301 || $http_code == 302 || $http_code == 303 || $http_code == 307) {
+			$matches = [];
+			preg_match('/(Location:|URI:)(.*?)\n/', $header, $matches);
+			$newurl = trim(array_pop($matches));
+
+			if (strpos($newurl, '/') === 0) {
+				$newurl = $old_location_info["scheme"] . "://" . $old_location_info["host"] . $newurl;
+			}
+
+			if (filter_var($newurl, FILTER_VALIDATE_URL)) {
+				$redirects++;
+				logger('post_url: redirect ' . $url . ' to ' . $newurl);
+				return post_url($newurl, $params, $headers, $redirects, $timeout);
+			}
+		}
+
+		$a->set_curl_code($http_code);
+
+		$body = substr($s, strlen($header));
+
+		$a->set_curl_headers($header);
+
+		curl_close($ch);
+
+		$a->save_timestamp($stamp1, 'network');
+
+		logger('post_url: end ' . $url, LOGGER_DATA);
+
+		return $body;
+	}
+
+	/**
+	 * Generic XML return
+	 * Outputs a basic dfrn XML status structure to STDOUT, with a <status> variable
+	 * of $st and an optional text <message> of $message and terminates the current process.
+	 */
+	public static function xmlStatus($st, $message = '')
+	{
+		$result = ['status' => $st];
+
+		if ($message != '') {
+			$result['message'] = $message;
+		}
+
+		if ($st) {
+			logger('xml_status returning non_zero: ' . $st . " message=" . $message);
+		}
+
+		header("Content-type: text/xml");
+
+		$xmldata = ["result" => $result];
+
+		echo XML::fromArray($xmldata, $xml);
+
+		killme();
+	}
+
+	/**
+	 * @brief Send HTTP status header and exit.
+	 *
+	 * @param integer $val         HTTP status result value
+	 * @param array   $description optional message
+	 *                             'title' => header title
+	 *                             'description' => optional message
+	 */
+	public static function httpStatusExit($val, $description = [])
+	{
+		$err = '';
+		if ($val >= 400) {
+			$err = 'Error';
+			if (!isset($description["title"])) {
+				$description["title"] = $err." ".$val;
+			}
+		}
+
+		if ($val >= 200 && $val < 300) {
+			$err = 'OK';
+		}
+
+		logger('http_status_exit ' . $val);
+		header($_SERVER["SERVER_PROTOCOL"] . ' ' . $val . ' ' . $err);
+
+		if (isset($description["title"])) {
+			$tpl = get_markup_template('http_status.tpl');
+			echo replace_macros(
+				$tpl,
+				[
+					'$title' => $description["title"],
+					'$description' => $description["description"]]
+			);
+		}
+
+		killme();
+	}
+
+	/**
+	 * @brief Check URL to se if ts's real
+	 *
+	 * Take a URL from the wild, prepend http:// if necessary
+	 * and check DNS to see if it's real (or check if is a valid IP address)
+	 *
+	 * @param string $url The URL to be validated
+	 * @return string|boolean The actual working URL, false else
+	 */
+	public static function validateURL($url)
+	{
+		if (Config::get('system', 'disable_url_validation')) {
+			return $url;
+		}
+
+		// no naked subdomains (allow localhost for tests)
+		if (strpos($url, '.') === false && strpos($url, '/localhost/') === false) {
+			return false;
+		}
+
+		if (substr($url, 0, 4) != 'http') {
+			$url = 'http://' . $url;
+		}
+
+		/// @TODO Really suppress function outcomes? Why not find them + debug them?
+		$h = @parse_url($url);
+
+		if ((is_array($h)) && (@dns_get_record($h['host'], DNS_A + DNS_CNAME + DNS_PTR) || filter_var($h['host'], FILTER_VALIDATE_IP) )) {
+			return $url;
+		}
+
+		return false;
+	}
+
+	/**
+	 * @brief Checks that email is an actual resolvable internet address
+	 *
+	 * @param string $addr The email address
+	 * @return boolean True if it's a valid email address, false if it's not
+	 */
+	public static function validateEmail($addr)
+	{
+		if (Config::get('system', 'disable_email_validation')) {
+			return true;
+		}
+
+		if (! strpos($addr, '@')) {
+			return false;
+		}
+
+		$h = substr($addr, strpos($addr, '@') + 1);
+
+		if (($h) && (dns_get_record($h, DNS_A + DNS_CNAME + DNS_PTR + DNS_MX) || filter_var($h, FILTER_VALIDATE_IP) )) {
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	 * @brief Check if URL is allowed
+	 *
+	 * Check $url against our list of allowed sites,
+	 * wildcards allowed. If allowed_sites is unset return true;
+	 *
+	 * @param string $url URL which get tested
+	 * @return boolean True if url is allowed otherwise return false
+	 */
+	public static function allowedURL($url)
+	{
+		$h = @parse_url($url);
+
+		if (! $h) {
+			return false;
+		}
+
+		$str_allowed = Config::get('system', 'allowed_sites');
+		if (! $str_allowed) {
+			return true;
+		}
+
+		$found = false;
+
+		$host = strtolower($h['host']);
+
+		// always allow our own site
+		if ($host == strtolower($_SERVER['SERVER_NAME'])) {
+			return true;
+		}
+
+		$fnmatch = function_exists('fnmatch');
+		$allowed = explode(',', $str_allowed);
+
+		if (count($allowed)) {
+			foreach ($allowed as $a) {
+				$pat = strtolower(trim($a));
+				if (($fnmatch && fnmatch($pat, $host)) || ($pat == $host)) {
+					$found = true;
+					break;
+				}
+			}
+		}
+		return $found;
+	}
+
+	/**
+	 * Checks if the provided url domain is on the domain blocklist.
+	 * Returns true if it is or malformed URL, false if not.
+	 *
+	 * @param string $url The url to check the domain from
+	 *
+	 * @return boolean
+	 */
+	public static function blockedURL($url)
+	{
+		$h = @parse_url($url);
+
+		if (! $h) {
+			return true;
+		}
+
+		$domain_blocklist = Config::get('system', 'blocklist', []);
+		if (! $domain_blocklist) {
+			return false;
+		}
+
+		$host = strtolower($h['host']);
+
+		foreach ($domain_blocklist as $domain_block) {
+			if (strtolower($domain_block['domain']) == $host) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * @brief Check if email address is allowed to register here.
+	 *
+	 * Compare against our list (wildcards allowed).
+	 *
+	 * @param  string $email email address
+	 * @return boolean False if not allowed, true if allowed
+	 *    or if allowed list is not configured
+	 */
+	public static function allowedEmail($email)
+	{
+		$domain = strtolower(substr($email, strpos($email, '@') + 1));
+		if (!$domain) {
+			return false;
+		}
+
+		$str_allowed = Config::get('system', 'allowed_email', '');
+		if (!x($str_allowed)) {
+			return true;
+		}
+
+		$allowed = explode(',', $str_allowed);
+
+		return allowed_domain($domain, $allowed);
+	}
+
+	/**
+	 * Checks for the existence of a domain in a domain list
+	 *
+	 * @brief Checks for the existence of a domain in a domain list
+	 * @param string $domain
+	 * @param array  $domain_list
+	 * @return boolean
+	 */
+	public static function allowedDomain($domain, array $domain_list)
+	{
+		$found = false;
+
+		foreach ($domain_list as $item) {
+			$pat = strtolower(trim($item));
+			if (fnmatch($pat, $domain) || ($pat == $domain)) {
+				$found = true;
+				break;
+			}
+		}
+
+		return $found;
+	}
+
+	public static function avatarImg($email)
+	{
+		$avatar['size'] = 175;
+		$avatar['email'] = $email;
+		$avatar['url'] = '';
+		$avatar['success'] = false;
+
+		Addon::callHooks('avatar_lookup', $avatar);
+
+		if (! $avatar['success']) {
+			$avatar['url'] = System::baseUrl() . '/images/person-175.jpg';
+		}
+
+		logger('Avatar: ' . $avatar['email'] . ' ' . $avatar['url'], LOGGER_DEBUG);
+		return $avatar['url'];
+	}
+
+	public static function parseXmlString($s, $strict = true)
+	{
+		// the "strict" parameter is deactivated
+
+		/// @todo Move this function to the xml class
+		libxml_use_internal_errors(true);
+
+		$x = @simplexml_load_string($s);
+		if (!$x) {
+			logger('libxml: parse: error: ' . $s, LOGGER_DATA);
+			foreach (libxml_get_errors() as $err) {
+				logger('libxml: parse: ' . $err->code." at ".$err->line.":".$err->column." : ".$err->message, LOGGER_DATA);
+			}
+			libxml_clear_errors();
+		}
+		return $x;
+	}
+
+	public static function scaleExternalImages($srctext, $include_link = true, $scale_replace = false)
+	{
+		// Suppress "view full size"
+		if (intval(Config::get('system', 'no_view_full_size'))) {
+			$include_link = false;
+		}
+
+		// Picture addresses can contain special characters
+		$s = htmlspecialchars_decode($srctext);
+
+		$matches = null;
+		$c = preg_match_all('/\[img.*?\](.*?)\[\/img\]/ism', $s, $matches, PREG_SET_ORDER);
+		if ($c) {
+			foreach ($matches as $mtch) {
+				logger('scale_external_image: ' . $mtch[1]);
+
+				$hostname = str_replace('www.', '', substr(System::baseUrl(), strpos(System::baseUrl(), '://') + 3));
+				if (stristr($mtch[1], $hostname)) {
+					continue;
+				}
+
+				// $scale_replace, if passed, is an array of two elements. The
+				// first is the name of the full-size image. The second is the
+				// name of a remote, scaled-down version of the full size image.
+				// This allows Friendica to display the smaller remote image if
+				// one exists, while still linking to the full-size image
+				if ($scale_replace) {
+					$scaled = str_replace($scale_replace[0], $scale_replace[1], $mtch[1]);
+				} else {
+					$scaled = $mtch[1];
+				}
+				$i = fetch_url($scaled);
+				if (! $i) {
+					return $srctext;
+				}
+
+				// guess mimetype from headers or filename
+				$type = Image::guessType($mtch[1], true);
+
+				if ($i) {
+					$Image = new Image($i, $type);
+					if ($Image->isValid()) {
+						$orig_width = $Image->getWidth();
+						$orig_height = $Image->getHeight();
+
+						if ($orig_width > 640 || $orig_height > 640) {
+							$Image->scaleDown(640);
+							$new_width = $Image->getWidth();
+							$new_height = $Image->getHeight();
+							logger('scale_external_images: ' . $orig_width . '->' . $new_width . 'w ' . $orig_height . '->' . $new_height . 'h' . ' match: ' . $mtch[0], LOGGER_DEBUG);
+							$s = str_replace(
+								$mtch[0],
+								'[img=' . $new_width . 'x' . $new_height. ']' . $scaled . '[/img]'
+								. "\n" . (($include_link)
+									? '[url=' . $mtch[1] . ']' . L10n::t('view full size') . '[/url]' . "\n"
+									: ''),
+								$s
+							);
+							logger('scale_external_images: new string: ' . $s, LOGGER_DEBUG);
+						}
+					}
+				}
+			}
+		}
+
+		// replace the special char encoding
+		$s = htmlspecialchars($s, ENT_NOQUOTES, 'UTF-8');
+		return $s;
+	}
+
+	public static function fixContactSslPolicy(&$contact, $new_policy)
+	{
+		$ssl_changed = false;
+		if ((intval($new_policy) == SSL_POLICY_SELFSIGN || $new_policy === 'self') && strstr($contact['url'], 'https:')) {
+			$ssl_changed = true;
+			$contact['url']     = 	str_replace('https:', 'http:', $contact['url']);
+			$contact['request'] = 	str_replace('https:', 'http:', $contact['request']);
+			$contact['notify']  = 	str_replace('https:', 'http:', $contact['notify']);
+			$contact['poll']    = 	str_replace('https:', 'http:', $contact['poll']);
+			$contact['confirm'] = 	str_replace('https:', 'http:', $contact['confirm']);
+			$contact['poco']    = 	str_replace('https:', 'http:', $contact['poco']);
+		}
+
+		if ((intval($new_policy) == SSL_POLICY_FULL || $new_policy === 'full') && strstr($contact['url'], 'http:')) {
+			$ssl_changed = true;
+			$contact['url']     = 	str_replace('http:', 'https:', $contact['url']);
+			$contact['request'] = 	str_replace('http:', 'https:', $contact['request']);
+			$contact['notify']  = 	str_replace('http:', 'https:', $contact['notify']);
+			$contact['poll']    = 	str_replace('http:', 'https:', $contact['poll']);
+			$contact['confirm'] = 	str_replace('http:', 'https:', $contact['confirm']);
+			$contact['poco']    = 	str_replace('http:', 'https:', $contact['poco']);
+		}
+
+		if ($ssl_changed) {
+			$fields = ['url' => $contact['url'], 'request' => $contact['request'],
+					'notify' => $contact['notify'], 'poll' => $contact['poll'],
+					'confirm' => $contact['confirm'], 'poco' => $contact['poco']];
+			dba::update('contact', $fields, ['id' => $contact['id']]);
+		}
+	}
+
+	/**
+	 * @brief Remove Google Analytics and other tracking platforms params from URL
+	 *
+	 * @param string $url Any user-submitted URL that may contain tracking params
+	 * @return string The same URL stripped of tracking parameters
+	 */
+	public static function stripTrackingQueryParams($url)
+	{
+		$urldata = parse_url($url);
+		if (is_string($urldata["query"])) {
+			$query = $urldata["query"];
+			parse_str($query, $querydata);
+
+			if (is_array($querydata)) {
+				foreach ($querydata as $param => $value) {
+					if (in_array(
+						$param,
+						[
+							"utm_source", "utm_medium", "utm_term", "utm_content", "utm_campaign",
+							"wt_mc", "pk_campaign", "pk_kwd", "mc_cid", "mc_eid",
+							"fb_action_ids", "fb_action_types", "fb_ref",
+							"awesm", "wtrid",
+							"woo_campaign", "woo_source", "woo_medium", "woo_content", "woo_term"]
+						)
+					) {
+						$pair = $param . "=" . urlencode($value);
+						$url = str_replace($pair, "", $url);
+
+						// Second try: if the url isn't encoded completely
+						$pair = $param . "=" . str_replace(" ", "+", $value);
+						$url = str_replace($pair, "", $url);
+
+						// Third try: Maybey the url isn't encoded at all
+						$pair = $param . "=" . $value;
+						$url = str_replace($pair, "", $url);
+
+						$url = str_replace(["?&", "&&"], ["?", ""], $url);
+					}
+				}
+			}
+
+			if (substr($url, -1, 1) == "?") {
+				$url = substr($url, 0, -1);
+			}
+		}
+
+		return $url;
+	}
+
+	/**
+	 * @brief Returns the original URL of the provided URL
+	 *
+	 * This function strips tracking query params and follows redirections, either
+	 * through HTTP code or meta refresh tags. Stops after 10 redirections.
+	 *
+	 * @todo Remove the $fetchbody parameter that generates an extraneous HEAD request
+	 *
+	 * @see ParseUrl::getSiteinfo
+	 *
+	 * @param string $url       A user-submitted URL
+	 * @param int    $depth     The current redirection recursion level (internal)
+	 * @param bool   $fetchbody Wether to fetch the body or not after the HEAD requests
+	 * @return string A canonical URL
+	 */
+	public static function originalURL($url, $depth = 1, $fetchbody = false)
+	{
+		$a = get_app();
+
+		$url = strip_tracking_query_params($url);
+
+		if ($depth > 10) {
+			return($url);
+		}
+
+		$url = trim($url, "'");
+
+		$stamp1 = microtime(true);
+
+		$ch = curl_init();
+		curl_setopt($ch, CURLOPT_URL, $url);
+		curl_setopt($ch, CURLOPT_HEADER, 1);
+		curl_setopt($ch, CURLOPT_NOBODY, 1);
+		curl_setopt($ch, CURLOPT_TIMEOUT, 10);
+		curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
+		curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
+
+		curl_exec($ch);
+		$curl_info = @curl_getinfo($ch);
+		$http_code = $curl_info['http_code'];
+		curl_close($ch);
+
+		$a->save_timestamp($stamp1, "network");
+
+		if ($http_code == 0) {
+			return($url);
+		}
+
+		if ((($curl_info['http_code'] == "301") || ($curl_info['http_code'] == "302"))
+			&& (($curl_info['redirect_url'] != "") || ($curl_info['location'] != ""))
+		) {
+			if ($curl_info['redirect_url'] != "") {
+				return(original_url($curl_info['redirect_url'], ++$depth, $fetchbody));
+			} else {
+				return(original_url($curl_info['location'], ++$depth, $fetchbody));
+			}
+		}
+
+		// Check for redirects in the meta elements of the body if there are no redirects in the header.
+		if (!$fetchbody) {
+			return(original_url($url, ++$depth, true));
+		}
+
+		// if the file is too large then exit
+		if ($curl_info["download_content_length"] > 1000000) {
+			return($url);
+		}
+
+		// if it isn't a HTML file then exit
+		if (($curl_info["content_type"] != "") && !strstr(strtolower($curl_info["content_type"]), "html")) {
+			return($url);
+		}
+
+		$stamp1 = microtime(true);
+
+		$ch = curl_init();
+		curl_setopt($ch, CURLOPT_URL, $url);
+		curl_setopt($ch, CURLOPT_HEADER, 0);
+		curl_setopt($ch, CURLOPT_NOBODY, 0);
+		curl_setopt($ch, CURLOPT_TIMEOUT, 10);
+		curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
+		curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
+
+		$body = curl_exec($ch);
+		curl_close($ch);
+
+		$a->save_timestamp($stamp1, "network");
+
+		if (trim($body) == "") {
+			return($url);
+		}
+
+		// Check for redirect in meta elements
+		$doc = new DOMDocument();
+		@$doc->loadHTML($body);
+
+		$xpath = new DomXPath($doc);
+
+		$list = $xpath->query("//meta[@content]");
+		foreach ($list as $node) {
+			$attr = [];
+			if ($node->attributes->length) {
+				foreach ($node->attributes as $attribute) {
+					$attr[$attribute->name] = $attribute->value;
+				}
+			}
+
+			if (@$attr["http-equiv"] == 'refresh') {
+				$path = $attr["content"];
+				$pathinfo = explode(";", $path);
+				foreach ($pathinfo as $value) {
+					if (substr(strtolower($value), 0, 4) == "url=") {
+						return(original_url(substr($value, 4), ++$depth));
+					}
+				}
+			}
+		}
+
+		return $url;
+	}
+
+	public static function shortLink($url)
+	{
+		$slinky = new Slinky($url);
+		$yourls_url = Config::get('yourls', 'url1');
+		if ($yourls_url) {
+			$yourls_username = Config::get('yourls', 'username1');
+			$yourls_password = Config::get('yourls', 'password1');
+			$yourls_ssl = Config::get('yourls', 'ssl1');
+			$yourls = new Slinky_YourLS();
+			$yourls->set('username', $yourls_username);
+			$yourls->set('password', $yourls_password);
+			$yourls->set('ssl', $yourls_ssl);
+			$yourls->set('yourls-url', $yourls_url);
+			$slinky->set_cascade([$yourls, new Slinky_Ur1ca(), new Slinky_TinyURL()]);
+		} else {
+			// setup a cascade of shortening services
+			// try to get a short link from these services
+			// in the order ur1.ca, tinyurl
+			$slinky->set_cascade([new Slinky_Ur1ca(), new Slinky_TinyURL()]);
+		}
+		return $slinky->short();
+	}
+
+	/**
+	 * @brief Encodes content to json
+	 *
+	 * This function encodes an array to json format
+	 * and adds an application/json HTTP header to the output.
+	 * After finishing the process is getting killed.
+	 *
+	 * @param array $x The input content
+	 */
+	public static function jsonReturnAndDie($x)
+	{
+		header("content-type: application/json");
+		echo json_encode($x);
+		killme();
+	}
+
+	/**
+	 * @brief Find the matching part between two url
+	 *
+	 * @param string $url1
+	 * @param string $url2
+	 * @return string The matching part
+	 */
+	public static function matchingURL($url1, $url2)
+	{
+		if (($url1 == "") || ($url2 == "")) {
+			return "";
+		}
+
+		$url1 = normalise_link($url1);
+		$url2 = normalise_link($url2);
+
+		$parts1 = parse_url($url1);
+		$parts2 = parse_url($url2);
+
+		if (!isset($parts1["host"]) || !isset($parts2["host"])) {
+			return "";
+		}
+
+		if ($parts1["scheme"] != $parts2["scheme"]) {
+			return "";
+		}
+
+		if ($parts1["host"] != $parts2["host"]) {
+			return "";
+		}
+
+		if ($parts1["port"] != $parts2["port"]) {
+			return "";
+		}
+
+		$match = $parts1["scheme"]."://".$parts1["host"];
+
+		if ($parts1["port"]) {
+			$match .= ":".$parts1["port"];
+		}
+
+		$pathparts1 = explode("/", $parts1["path"]);
+		$pathparts2 = explode("/", $parts2["path"]);
+
+		$i = 0;
+		$path = "";
+		do {
+			$path1 = $pathparts1[$i];
+			$path2 = $pathparts2[$i];
+
+			if ($path1 == $path2) {
+				$path .= $path1."/";
+			}
+		} while (($path1 == $path2) && ($i++ <= count($pathparts1)));
+
+		$match .= $path;
+
+		return normalise_link($match);
+	}
+
+	/**
+	 * @brief Glue url parts together
+	 *
+	 * @param array $parsed URL parts
+	 *
+	 * @return string The glued URL
+	 */
+	public static function unParseURL($parsed)
+	{
+		$get = function ($key) use ($parsed) {
+			return isset($parsed[$key]) ? $parsed[$key] : null;
+		};
+
+		$pass      = $get('pass');
+		$user      = $get('user');
+		$userinfo  = $pass !== null ? "$user:$pass" : $user;
+		$port      = $get('port');
+		$scheme    = $get('scheme');
+		$query     = $get('query');
+		$fragment  = $get('fragment');
+		$authority = ($userinfo !== null ? $userinfo."@" : '') .
+						$get('host') .
+						($port ? ":$port" : '');
+
+		return	(strlen($scheme) ? $scheme.":" : '') .
+			(strlen($authority) ? "//".$authority : '') .
+			$get('path') .
+			(strlen($query) ? "?".$query : '') .
+			(strlen($fragment) ? "#".$fragment : '');
+	}
+}