ttrss/classes/urlhelper.php

610 lines
19 KiB
PHP

<?php
class UrlHelper {
const EXTRA_HREF_SCHEMES = [
"magnet",
"mailto",
"tel"
];
const EXTRA_SCHEMES_BY_CONTENT_TYPE = [
"application/x-bittorrent" => [ "magnet" ],
];
// TODO: class properties can be switched to PHP typing if/when the minimum PHP_VERSION is raised to 7.4.0+
/** @var string */
static $fetch_last_error;
/** @var int */
static $fetch_last_error_code;
/** @var string */
static $fetch_last_error_content;
/** @var string */
static $fetch_last_content_type;
/** @var string */
static $fetch_last_modified;
/** @var string */
static $fetch_effective_url;
/** @var string */
static $fetch_effective_ip_addr;
/** @var bool */
static $fetch_curl_used;
/**
* @param array<string, string|int> $parts
*/
static function build_url(array $parts): string {
$tmp = $parts['scheme'] . "://" . $parts['host'];
if (isset($parts['path'])) $tmp .= $parts['path'];
if (isset($parts['query'])) $tmp .= '?' . $parts['query'];
if (isset($parts['fragment'])) $tmp .= '#' . $parts['fragment'];
return $tmp;
}
/**
* Converts a (possibly) relative URL to a absolute one, using provided base URL.
* Provides some exceptions for additional schemes like data: if called with owning element/attribute.
*
* @param string $base_url Base URL (i.e. from where the document is)
* @param string $rel_url Possibly relative URL in the document
* @param string $owner_element Owner element tag name (i.e. "a") (optional)
* @param string $owner_attribute Owner attribute (i.e. "href") (optional)
* @param string $content_type URL content type as specified by enclosures, etc.
*
* @return false|string Absolute URL or false on failure (either during URL parsing or validation)
*/
public static function rewrite_relative($base_url,
$rel_url,
string $owner_element = "",
string $owner_attribute = "",
string $content_type = "") {
$rel_parts = parse_url($rel_url);
if (!$rel_url) return $base_url;
/**
* If parse_url failed to parse $rel_url return false to match the current "invalid thing" behavior
* of UrlHelper::validate().
*
* TODO: There are many places where a string return value is assumed. We should either update those
* to account for the possibility of failure, or look into updating this function's return values.
*/
if ($rel_parts === false) {
return false;
}
if (!empty($rel_parts['host']) && !empty($rel_parts['scheme'])) {
return self::validate($rel_url);
// protocol-relative URL (rare but they exist)
} else if (strpos($rel_url, "//") === 0) {
return self::validate("https:" . $rel_url);
// allow some extra schemes for A href
} else if (in_array($rel_parts["scheme"] ?? "", self::EXTRA_HREF_SCHEMES, true) &&
$owner_element == "a" &&
$owner_attribute == "href") {
return $rel_url;
// allow some extra schemes for links with feed-specified content type i.e. enclosures
} else if ($content_type &&
isset(self::EXTRA_SCHEMES_BY_CONTENT_TYPE[$content_type]) &&
in_array($rel_parts["scheme"], self::EXTRA_SCHEMES_BY_CONTENT_TYPE[$content_type])) {
return $rel_url;
// allow limited subset of inline base64-encoded images for IMG elements
} else if (($rel_parts["scheme"] ?? "") == "data" &&
preg_match('%^image/(webp|gif|jpg|png|svg);base64,%', $rel_parts["path"]) &&
$owner_element == "img" &&
$owner_attribute == "src") {
return $rel_url;
} else {
$base_parts = parse_url($base_url);
$rel_parts['host'] = $base_parts['host'] ?? "";
$rel_parts['scheme'] = $base_parts['scheme'] ?? "";
if ($rel_parts['path'] ?? "") {
// we append dirname() of base path to relative URL path as per RFC 3986 section 5.2.2
$base_path = with_trailing_slash(dirname($base_parts['path'] ?? ""));
// 1. absolute relative path (/test.html) = no-op, proceed as is
// 2. dotslash relative URI (./test.html) - strip "./", append base path
if (strpos($rel_parts['path'], './') === 0) {
$rel_parts['path'] = $base_path . substr($rel_parts['path'], 2);
// 3. anything else relative (test.html) - append dirname() of base path
} else if (strpos($rel_parts['path'], '/') !== 0) {
$rel_parts['path'] = $base_path . $rel_parts['path'];
}
//$rel_parts['path'] = str_replace("/./", "/", $rel_parts['path']);
//$rel_parts['path'] = str_replace("//", "/", $rel_parts['path']);
}
return self::validate(self::build_url($rel_parts));
}
}
/** extended filtering involves validation for safe ports and loopback
* @return false|string false if something went wrong, otherwise the URL string
*/
static function validate(string $url, bool $extended_filtering = false) {
$url = clean($url);
# fix protocol-relative URLs
if (strpos($url, "//") === 0)
$url = "https:" . $url;
$tokens = parse_url($url);
// this isn't really necessary because filter_var(... FILTER_VALIDATE_URL) requires host and scheme
// as per https://php.watch/versions/7.3/filter-var-flag-deprecation but it might save time
if (empty($tokens['host']))
return false;
if (!in_array(strtolower($tokens['scheme']), ['http', 'https']))
return false;
//convert IDNA hostname to punycode if possible
if (function_exists("idn_to_ascii")) {
if (mb_detect_encoding($tokens['host']) != 'ASCII') {
if (defined('IDNA_NONTRANSITIONAL_TO_ASCII') && defined('INTL_IDNA_VARIANT_UTS46')) {
$tokens['host'] = idn_to_ascii($tokens['host'], IDNA_NONTRANSITIONAL_TO_ASCII, INTL_IDNA_VARIANT_UTS46);
} else {
$tokens['host'] = idn_to_ascii($tokens['host']);
}
// if `idn_to_ascii` failed
if ($tokens['host'] === false) {
return false;
}
}
}
// separate set of tokens with urlencoded 'path' because filter_var() rightfully fails on non-latin characters
// (used for validation only, we actually request the original URL, in case of urlencode breaking it)
$tokens_filter_var = $tokens;
if ($tokens['path'] ?? false) {
$tokens_filter_var['path'] = implode("/",
array_map("rawurlencode",
array_map("rawurldecode",
explode("/", $tokens['path']))));
}
$url = self::build_url($tokens);
$url_filter_var = self::build_url($tokens_filter_var);
if (filter_var($url_filter_var, FILTER_VALIDATE_URL) === false)
return false;
if ($extended_filtering) {
if (!in_array($tokens['port'] ?? '', [80, 443, '']))
return false;
if (strtolower($tokens['host']) == 'localhost' || $tokens['host'] == '::1' || strpos($tokens['host'], '127.') === 0)
return false;
}
return $url;
}
/**
* @return false|string
*/
static function resolve_redirects(string $url, int $timeout, int $nest = 0) {
// too many redirects
if ($nest > 10)
return false;
if (version_compare(PHP_VERSION, '7.1.0', '>=')) {
$context_options = array(
'http' => array(
'header' => array(
'Connection: close'
),
'method' => 'HEAD',
'timeout' => $timeout,
'protocol_version'=> 1.1)
);
if (Config::get(Config::HTTP_PROXY)) {
$context_options['http']['request_fulluri'] = true;
$context_options['http']['proxy'] = Config::get(Config::HTTP_PROXY);
}
$context = stream_context_create($context_options);
// PHP 8 changed the second param from int to bool, but we still support PHP >= 7.1.0
// @phpstan-ignore-next-line
$headers = get_headers($url, 0, $context);
} else {
// PHP 8 changed the second param from int to bool, but we still support PHP >= 7.1.0
// @phpstan-ignore-next-line
$headers = get_headers($url, 0);
}
if (is_array($headers)) {
$headers = array_reverse($headers); // last one is the correct one
foreach($headers as $header) {
if (stripos($header, 'Location:') === 0) {
$url = self::rewrite_relative($url, trim(substr($header, strlen('Location:'))));
return self::resolve_redirects($url, $timeout, $nest + 1);
}
}
return $url;
}
// request failed?
return false;
}
/**
* @param array<string, bool|int|string>|string $options
* @return false|string false if something went wrong, otherwise string contents
*/
// TODO: max_size currently only works for CURL transfers
// TODO: multiple-argument way is deprecated, first parameter is a hash now
public static function fetch($options /* previously: 0: $url , 1: $type = false, 2: $login = false, 3: $pass = false,
4: $post_query = false, 5: $timeout = false, 6: $timestamp = 0, 7: $useragent = false*/) {
self::$fetch_last_error = "";
self::$fetch_last_error_code = -1;
self::$fetch_last_error_content = "";
self::$fetch_last_content_type = "";
self::$fetch_curl_used = false;
self::$fetch_last_modified = "";
self::$fetch_effective_url = "";
self::$fetch_effective_ip_addr = "";
if (!is_array($options)) {
// falling back on compatibility shim
$option_names = [ "url", "type", "login", "pass", "post_query", "timeout", "last_modified", "useragent" ];
$tmp = [];
for ($i = 0; $i < func_num_args(); $i++) {
$tmp[$option_names[$i]] = func_get_arg($i);
}
$options = $tmp;
/*$options = array(
"url" => func_get_arg(0),
"type" => @func_get_arg(1),
"login" => @func_get_arg(2),
"pass" => @func_get_arg(3),
"post_query" => @func_get_arg(4),
"timeout" => @func_get_arg(5),
"timestamp" => @func_get_arg(6),
"useragent" => @func_get_arg(7)
); */
}
$url = $options["url"];
$type = isset($options["type"]) ? $options["type"] : false;
$login = isset($options["login"]) ? $options["login"] : false;
$pass = isset($options["pass"]) ? $options["pass"] : false;
$post_query = isset($options["post_query"]) ? $options["post_query"] : false;
$timeout = isset($options["timeout"]) ? $options["timeout"] : false;
$last_modified = isset($options["last_modified"]) ? $options["last_modified"] : "";
$useragent = isset($options["useragent"]) ? $options["useragent"] : false;
$followlocation = isset($options["followlocation"]) ? $options["followlocation"] : true;
$max_size = isset($options["max_size"]) ? $options["max_size"] : Config::get(Config::MAX_DOWNLOAD_FILE_SIZE); // in bytes
$http_accept = isset($options["http_accept"]) ? $options["http_accept"] : false;
$http_referrer = isset($options["http_referrer"]) ? $options["http_referrer"] : false;
$url = ltrim($url, ' ');
$url = str_replace(' ', '%20', $url);
Debug::log("[UrlHelper] fetching: $url", Debug::LOG_EXTENDED);
$url = self::validate($url, true);
if (!$url) {
self::$fetch_last_error = "Requested URL failed extended validation.";
return false;
}
$url_host = parse_url($url, PHP_URL_HOST);
$ip_addr = gethostbyname($url_host);
if (!$ip_addr || strpos($ip_addr, "127.") === 0) {
self::$fetch_last_error = "URL hostname failed to resolve or resolved to a loopback address ($ip_addr)";
return false;
}
if (function_exists('curl_init') && !ini_get("open_basedir")) {
self::$fetch_curl_used = true;
$ch = curl_init($url);
if (!$ch) return false;
$curl_http_headers = [];
if ($last_modified && !$post_query)
array_push($curl_http_headers, "If-Modified-Since: $last_modified");
if ($http_accept)
array_push($curl_http_headers, "Accept: " . $http_accept);
if (count($curl_http_headers) > 0)
curl_setopt($ch, CURLOPT_HTTPHEADER, $curl_http_headers);
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, $timeout ? $timeout : Config::get(Config::FILE_FETCH_CONNECT_TIMEOUT));
curl_setopt($ch, CURLOPT_TIMEOUT, $timeout ? $timeout : Config::get(Config::FILE_FETCH_TIMEOUT));
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, $followlocation);
curl_setopt($ch, CURLOPT_MAXREDIRS, 20);
curl_setopt($ch, CURLOPT_BINARYTRANSFER, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HEADER, true);
curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
curl_setopt($ch, CURLOPT_USERAGENT, $useragent ? $useragent : Config::get_user_agent());
curl_setopt($ch, CURLOPT_ENCODING, "");
curl_setopt($ch, CURLOPT_COOKIEJAR, "/dev/null");
if ($http_referrer)
curl_setopt($ch, CURLOPT_REFERER, $http_referrer);
if ($max_size) {
curl_setopt($ch, CURLOPT_NOPROGRESS, false);
curl_setopt($ch, CURLOPT_BUFFERSIZE, 16384); // needed to get 5 arguments in progress function?
// holy shit closures in php
// download & upload are *expected* sizes respectively, could be zero
curl_setopt($ch, CURLOPT_PROGRESSFUNCTION, function($curl_handle, $download_size, $downloaded, $upload_size, $uploaded) use(&$max_size, $url) {
//Debug::log("[curl progressfunction] $downloaded $max_size", Debug::$LOG_EXTENDED);
if ($downloaded > $max_size) {
Debug::log("[UrlHelper] fetch error: curl reached max size of $max_size bytes downloading $url, aborting.", Debug::LOG_VERBOSE);
return 1;
}
return 0;
});
}
if (Config::get(Config::HTTP_PROXY)) {
curl_setopt($ch, CURLOPT_PROXY, Config::get(Config::HTTP_PROXY));
}
if ($post_query) {
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $post_query);
}
if ($login && $pass)
curl_setopt($ch, CURLOPT_USERPWD, "$login:$pass");
$ret = @curl_exec($ch);
if (curl_errno($ch) === 23 || curl_errno($ch) === 61) {
curl_setopt($ch, CURLOPT_ENCODING, 'none');
$ret = @curl_exec($ch);
}
$headers_length = curl_getinfo($ch, CURLINFO_HEADER_SIZE);
$headers = explode("\r\n", substr($ret, 0, $headers_length));
$contents = substr($ret, $headers_length);
foreach ($headers as $header) {
if (strstr($header, ": ") !== false) {
list ($key, $value) = explode(": ", $header);
if (strtolower($key) == "last-modified") {
self::$fetch_last_modified = $value;
}
}
if (substr(strtolower($header), 0, 7) == 'http/1.') {
self::$fetch_last_error_code = (int) substr($header, 9, 3);
self::$fetch_last_error = $header;
}
}
$http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
self::$fetch_last_content_type = curl_getinfo($ch, CURLINFO_CONTENT_TYPE);
self::$fetch_effective_url = curl_getinfo($ch, CURLINFO_EFFECTIVE_URL);
if (!self::validate(self::$fetch_effective_url, true)) {
self::$fetch_last_error = "URL received after redirection failed extended validation.";
return false;
}
self::$fetch_effective_ip_addr = gethostbyname(parse_url(self::$fetch_effective_url, PHP_URL_HOST));
if (!self::$fetch_effective_ip_addr || strpos(self::$fetch_effective_ip_addr, "127.") === 0) {
self::$fetch_last_error = "URL hostname received after redirection failed to resolve or resolved to a loopback address (".self::$fetch_effective_ip_addr.")";
return false;
}
self::$fetch_last_error_code = $http_code;
if ($http_code != 200 || $type && strpos(self::$fetch_last_content_type, "$type") === false) {
if (curl_errno($ch) != 0) {
self::$fetch_last_error .= "; " . curl_errno($ch) . " " . curl_error($ch);
} else {
self::$fetch_last_error = "HTTP Code: $http_code ";
}
self::$fetch_last_error_content = $contents;
curl_close($ch);
return false;
}
if (!$contents) {
self::$fetch_last_error = curl_errno($ch) . " " . curl_error($ch);
curl_close($ch);
return false;
}
curl_close($ch);
$is_gzipped = RSSUtils::is_gzipped($contents);
if ($is_gzipped && is_string($contents)) {
$tmp = @gzdecode($contents);
if ($tmp) $contents = $tmp;
}
return $contents;
} else {
self::$fetch_curl_used = false;
if ($login && $pass){
$url_parts = array();
preg_match("/(^[^:]*):\/\/(.*)/", $url, $url_parts);
$pass = urlencode($pass);
if ($url_parts[1] && $url_parts[2]) {
$url = $url_parts[1] . "://$login:$pass@" . $url_parts[2];
}
}
// TODO: should this support POST requests or not? idk
$context_options = array(
'http' => array(
'header' => array(
'Connection: close'
),
'method' => 'GET',
'ignore_errors' => true,
'timeout' => $timeout ? $timeout : Config::get(Config::FILE_FETCH_TIMEOUT),
'protocol_version'=> 1.1)
);
if (!$post_query && $last_modified)
array_push($context_options['http']['header'], "If-Modified-Since: $last_modified");
if ($http_accept)
array_push($context_options['http']['header'], "Accept: $http_accept");
if ($http_referrer)
array_push($context_options['http']['header'], "Referer: $http_referrer");
if (Config::get(Config::HTTP_PROXY)) {
$context_options['http']['request_fulluri'] = true;
$context_options['http']['proxy'] = Config::get(Config::HTTP_PROXY);
}
$context = stream_context_create($context_options);
$old_error = error_get_last();
self::$fetch_effective_url = self::resolve_redirects($url, $timeout ? $timeout : Config::get(Config::FILE_FETCH_CONNECT_TIMEOUT));
if (!self::validate(self::$fetch_effective_url, true)) {
self::$fetch_last_error = "URL received after redirection failed extended validation.";
return false;
}
self::$fetch_effective_ip_addr = gethostbyname(parse_url(self::$fetch_effective_url, PHP_URL_HOST));
if (!self::$fetch_effective_ip_addr || strpos(self::$fetch_effective_ip_addr, "127.") === 0) {
self::$fetch_last_error = "URL hostname received after redirection failed to resolve or resolved to a loopback address (".self::$fetch_effective_ip_addr.")";
return false;
}
$data = @file_get_contents($url, false, $context);
foreach ($http_response_header as $header) {
if (strstr($header, ": ") !== false) {
list ($key, $value) = explode(": ", $header);
$key = strtolower($key);
if ($key == 'content-type') {
self::$fetch_last_content_type = $value;
// don't abort here b/c there might be more than one
// e.g. if we were being redirected -- last one is the right one
} else if ($key == 'last-modified') {
self::$fetch_last_modified = $value;
} else if ($key == 'location') {
self::$fetch_effective_url = $value;
}
}
if (substr(strtolower($header), 0, 7) == 'http/1.') {
self::$fetch_last_error_code = (int) substr($header, 9, 3);
self::$fetch_last_error = $header;
}
}
if (self::$fetch_last_error_code != 200) {
$error = error_get_last();
if (($error['message'] ?? '') != ($old_error['message'] ?? '')) {
self::$fetch_last_error .= "; " . $error["message"];
}
self::$fetch_last_error_content = $data;
return false;
}
$is_gzipped = RSSUtils::is_gzipped($data);
if ($is_gzipped && $data) {
$tmp = @gzdecode($data);
if ($tmp) $data = $tmp;
}
return $data;
}
}
/**
* @return false|string false if the provided URL didn't match expected patterns, otherwise the video ID string
*/
public static function url_to_youtube_vid(string $url) {
$url = str_replace("youtube.com", "youtube-nocookie.com", $url);
$regexps = [
"/\/\/www\.youtube-nocookie\.com\/v\/([\w-]+)/",
"/\/\/www\.youtube-nocookie\.com\/embed\/([\w-]+)/",
"/\/\/www\.youtube-nocookie\.com\/watch?v=([\w-]+)/",
"/\/\/youtu.be\/([\w-]+)/",
];
foreach ($regexps as $re) {
$matches = [];
if (preg_match($re, $url, $matches)) {
return $matches[1];
}
}
return false;
}
}