phpmyadmin/src/Core.php
XananasX7 26d7ba4417
security: add allowed_classes => false to Core::safeUnserialize() as defence-in-depth
Core::safeUnserialize() validates the serialized string with a custom parser
before calling unserialize(). The parser only permits scalar types (s, b, i,
d, N) and plain arrays (a), blocking object tokens ('O:' / 'C:'). However,
the final unserialize() call does not pass allowed_classes, which means a
parser bypass or edge-case in the manual tokeniser could still allow object
instantiation.

Adding allowed_classes => false ensures that even if the manual validator is
somehow bypassed (e.g., by a future PHP serialization format change or a
subtle parser bug), unserialize() itself will refuse to instantiate PHP
objects — providing a second layer of protection.

Signed-off-by: El Mehdi Abenhazou <mehdiananas007@gmail.com>
2026-06-03 10:41:11 -03:00

736 lines
21 KiB
PHP

<?php
declare(strict_types=1);
namespace PhpMyAdmin;
use DateTimeZone;
use PhpMyAdmin\Clock\Clock;
use PhpMyAdmin\Error\ErrorHandler;
use PhpMyAdmin\Exceptions\MissingExtensionException;
use PhpMyAdmin\Http\ServerRequest;
use Psr\Clock\ClockInterface;
use Twig\Attribute\AsTwigFilter;
use function __;
use function array_pop;
use function array_walk_recursive;
use function chr;
use function count;
use function explode;
use function filter_var;
use function function_exists;
use function getenv;
use function hash_equals;
use function hash_hmac;
use function header;
use function header_remove;
use function htmlspecialchars;
use function http_build_query;
use function in_array;
use function is_array;
use function is_scalar;
use function is_string;
use function json_decode;
use function mb_strpos;
use function mb_substr;
use function parse_str;
use function parse_url;
use function preg_match;
use function preg_replace;
use function sprintf;
use function str_replace;
use function stripos;
use function strlen;
use function strpos;
use function substr;
use function unserialize;
use function urldecode;
use const FILTER_VALIDATE_IP;
/**
* Core functions used all over the scripts.
*/
class Core
{
/**
* Removes insecure parts in a path; used before include() or
* require() when a part of the path comes from an insecure source
* like a cookie or form.
*
* @param string $path The path to check
*/
public static function securePath(string $path): string
{
// change .. to .
return (string) preg_replace('@\.\.*@', '.', $path);
}
/**
* Returns a link to the PHP documentation
*
* @param string $target anchor in documentation
*
* @return string the URL
*/
public static function getPHPDocLink(string $target): string
{
/* List of PHP documentation translations */
$phpDocLanguages = ['pt_BR', 'zh_CN', 'fr', 'de', 'ja', 'ru', 'es', 'tr'];
$lang = 'en';
if (in_array(Current::$lang, $phpDocLanguages, true)) {
$lang = Current::$lang === 'zh_CN' ? 'zh' : Current::$lang;
}
return self::linkURL('https://www.php.net/manual/' . $lang . '/' . $target);
}
/**
* Warn or fail on missing extension.
*
* @param string $extension Extension name
* @param bool $fatal Whether the error is fatal.
* @param string $extra Extra string to append to message.
*/
public static function warnMissingExtension(
string $extension,
bool $fatal = false,
string $extra = '',
): void {
$message = 'The %s extension is missing. Please check your PHP configuration.';
/* Gettext does not have to be loaded yet here */
if (function_exists('__')) {
$message = __('The %s extension is missing. Please check your PHP configuration.');
}
$doclink = self::getPHPDocLink('book.' . $extension . '.php');
$message = sprintf($message, '[a@' . $doclink . '@Documentation][em]' . $extension . '[/em][/a]');
if ($extra !== '') {
$message .= ' ' . $extra;
}
if ($fatal) {
throw new MissingExtensionException(Sanitize::convertBBCode($message));
}
ErrorHandler::getInstance()->addUserError($message, false);
}
/**
* Checks if the given $page is index.php and returns true if valid.
* It ignores query parameters in $page (script.php?ignored)
*/
public static function checkPageValidity(string $page): bool
{
if ($page === '') {
return false;
}
if ($page === 'index.php') {
return true;
}
$newPage = mb_substr(
$page,
0,
(int) mb_strpos($page . '?', '?'),
);
if ($newPage === 'index.php') {
return true;
}
$newPage = urldecode($page);
$newPage = mb_substr(
$newPage,
0,
(int) mb_strpos($newPage . '?', '?'),
);
return $newPage === 'index.php';
}
/**
* Tries to find the value for the given environment variable name
*
* Searches in $_SERVER, $_ENV then tries getenv() and apache_getenv() in this order.
*
* @psalm-param non-empty-string $variableName
*/
public static function getEnv(string $variableName): string
{
$value = $_SERVER[$variableName] ?? $_ENV[$variableName] ?? getenv($variableName);
if (is_scalar($value) && (string) $value !== '') {
return (string) $value;
}
if (function_exists('apache_getenv')) {
return (string) apache_getenv($variableName, true); // @codeCoverageIgnore
}
return '';
}
/**
* Returns application/json headers. This includes no caching.
*
* @return array<string, string>
*/
public static function headerJSON(ClockInterface|null $clock = null): array
{
// No caching
$headers = self::getNoCacheHeaders($clock ?? new Clock());
// Media type
$headers['Content-Type'] = 'application/json; charset=UTF-8';
/**
* Disable content sniffing in browser.
* This is needed in case we include HTML in JSON, browser might assume it's html to display.
*/
$headers['X-Content-Type-Options'] = 'nosniff';
return $headers;
}
/** @return array<string, string> */
public static function getNoCacheHeaders(ClockInterface $clock): array
{
$headers = [];
$formattedDateTime = $clock->now()->setTimezone(new DateTimeZone('UTC'))->format('D, d M Y H:i:s \G\M\T');
// rfc2616 - Section 14.21
$headers['Expires'] = $formattedDateTime;
// HTTP/1.1
$headers['Cache-Control'] = 'no-store, no-cache, must-revalidate, pre-check=0, post-check=0, max-age=0';
// HTTP/1.0
$headers['Pragma'] = 'no-cache';
// test case: exporting a database into a .gz file with Safari
// would produce files not having the current time
// (added this header for Safari but should not harm other browsers)
$headers['Last-Modified'] = $formattedDateTime;
return $headers;
}
/**
* @param string $filename Filename to include in headers if empty, none Content-Disposition header will be sent.
* @param string $mimetype MIME type to include in headers.
* @param int $length Length of content (optional)
*
* @return array<string, string>
*/
public static function getDownloadHeaders(
ClockInterface $clock,
string $filename,
string $mimetype,
int $length = 0,
): array {
$headers = self::getNoCacheHeaders($clock);
/* Replace all possibly dangerous chars in filename */
$filename = Sanitize::sanitizeFilename($filename);
if ($filename !== '') {
$headers['Content-Description'] = 'File Transfer';
$headers['Content-Disposition'] = 'attachment; filename="' . $filename . '"';
}
$headers['Content-Type'] = $mimetype;
$headers['Content-Transfer-Encoding'] = 'binary';
if ($length > 0) {
$headers['Content-Length'] = (string) $length;
}
return $headers;
}
/**
* Sends header indicating file download.
*
* @param string $filename Filename to include in headers if empty, none Content-Disposition header will be sent.
* @param string $mimetype MIME type to include in headers.
* @param int $length Length of content (optional)
*/
public static function downloadHeader(string $filename, string $mimetype, int $length = 0): void
{
$headers = self::getDownloadHeaders(new Clock(), $filename, $mimetype, $length);
// The default output in PMA uses gzip,
// so if we want to output uncompressed file, we should reset the encoding.
// See PHP bug https://github.com/php/php-src/issues/8218
header_remove('Content-Encoding');
foreach ($headers as $name => $value) {
header(sprintf('%s: %s', $name, $value));
}
}
/**
* Returns value of an element in $array given by $path.
* $path is a string describing position of an element in an associative array,
* eg. Servers/1/host refers to $array[Servers][1][host]
*
* @param string $path path in the array
* @param mixed[] $array the array
* @param mixed $default default value
*
* @return mixed[]|mixed|null array element or $default
*/
public static function arrayRead(string $path, array $array, mixed $default = null): mixed
{
$keys = explode('/', $path);
$value =& $array;
foreach ($keys as $key) {
if (! isset($value[$key])) {
return $default;
}
$value =& $value[$key];
}
return $value;
}
/**
* Stores value in an array
*
* @param string $path path in the array
* @param mixed[] $array the array
* @param mixed $value value to store
*/
public static function arrayWrite(string $path, array &$array, mixed $value): void
{
$keys = explode('/', $path);
$lastKey = array_pop($keys);
$a =& $array;
foreach ($keys as $key) {
if (! isset($a[$key])) {
$a[$key] = [];
}
$a =& $a[$key];
}
$a[$lastKey] = $value;
}
/**
* Removes value from an array
*
* @param string $path path in the array
* @param mixed[] $array the array
*/
public static function arrayRemove(string $path, array &$array): void
{
$keys = explode('/', $path);
$keysLast = array_pop($keys);
$path = [];
$depth = 0;
$path[0] =& $array;
$found = true;
// go as deep as required or possible
foreach ($keys as $key) {
if (! isset($path[$depth][$key])) {
$found = false;
break;
}
$depth++;
$path[$depth] =& $path[$depth - 1][$key];
}
// if element found, remove it
if ($found) {
unset($path[$depth][$keysLast]);
$depth--;
}
// remove empty nested arrays
/** @infection-ignore-all */
for (; $depth >= 0; $depth--) {
if (isset($path[$depth + 1]) && count($path[$depth + 1]) !== 0) {
break;
}
unset($path[$depth][$keys[$depth]]);
}
}
/**
* Returns link to (possibly) external site using defined redirector.
*
* @param string $url URL where to go.
*
* @return string URL for a link.
*/
#[AsTwigFilter('link')]
public static function linkURL(string $url): string
{
if (preg_match('#^https?://#', $url) !== 1) {
return $url;
}
$params = [];
$params['url'] = $url;
$url = Url::getCommon($params);
//strip off token and such sensitive information. Just keep url.
$arr = parse_url($url);
if (! is_array($arr)) {
$arr = [];
}
parse_str($arr['query'] ?? '', $vars);
$query = http_build_query(['url' => $vars['url']]);
if (Config::getInstance()->isSetup()) {
return '../index.php?route=/url&' . $query;
}
return 'index.php?route=/url&' . $query;
}
/**
* Checks whether domain of URL is an allowed domain or not.
* Use only for URLs of external sites.
*
* @param string $url URL of external site.
*/
public static function isAllowedDomain(string $url): bool
{
$parsedUrl = parse_url($url);
if (
! is_array($parsedUrl)
|| ! isset($parsedUrl['host'])
|| isset($parsedUrl['user'])
|| isset($parsedUrl['pass'])
|| isset($parsedUrl['port'])
) {
return false;
}
$domainAllowList = [
/* Include current domain */
$_SERVER['SERVER_NAME'],
/* phpMyAdmin domains */
'wiki.phpmyadmin.net',
'www.phpmyadmin.net',
'phpmyadmin.net',
'demo.phpmyadmin.net',
'docs.phpmyadmin.net',
/* mysql.com domains */
'dev.mysql.com',
'bugs.mysql.com',
/* mariadb domains */
'mariadb.org',
'mariadb.com',
/* php.net domains */
'php.net',
'www.php.net',
/* Github domains*/
'github.com',
'www.github.com',
/* Percona domains */
'www.percona.com',
/* CVE domain */
'www.cve.org',
/* Following are doubtful ones. */
'mysqldatabaseadministration.blogspot.com',
];
return in_array($parsedUrl['host'], $domainAllowList, true);
}
/**
* Replace some html-unfriendly stuff
*
* @param string $buffer String to process
*
* @return string Escaped and cleaned up text suitable for html
*/
public static function mimeDefaultFunction(string $buffer): string
{
$buffer = htmlspecialchars($buffer);
$buffer = str_replace(' ', ' &nbsp;', $buffer);
return (string) preg_replace("@((\015\012)|(\015)|(\012))@", '<br>' . "\n", $buffer);
}
/**
* recursively check if variable is empty
*
* @param mixed $value the variable
*/
public static function emptyRecursive(mixed $value): bool
{
if (is_array($value)) {
$empty = true;
array_walk_recursive(
$value,
/** @param mixed $item */
static function ($item) use (&$empty): void {
$empty = $empty && empty($item);
},
);
return $empty;
}
return empty($value);
}
/**
* Gets the "true" IP address of the current user
*
* @return string|bool the ip of the user
*/
public static function getIp(): string|bool
{
/* Get the address of user */
if (empty($_SERVER['REMOTE_ADDR'])) {
/* We do not know remote IP */
return false;
}
$directIp = $_SERVER['REMOTE_ADDR'];
/* Do we trust this IP as a proxy? If yes we will use it's header. */
$config = Config::getInstance();
if (! isset($config->settings['TrustedProxies'][$directIp])) {
/* Return true IP */
return $directIp;
}
/**
* Parse header in form:
* X-Forwarded-For: client, proxy1, proxy2
*/
// Get header content
$value = self::getEnv($config->settings['TrustedProxies'][$directIp]);
// Grab first element what is client adddress
$value = explode(',', $value)[0];
// checks that the header contains only one IP address,
$isIp = filter_var($value, FILTER_VALIDATE_IP);
if ($isIp !== false) {
// True IP behind a proxy
return $value;
}
// We could not parse header
return false;
}
/**
* Sanitizes MySQL hostname
*
* * strips p: prefix(es)
*
* @param string $name User given hostname
*/
public static function sanitizeMySQLHost(string $name): string
{
while (stripos($name, 'p:') === 0) {
/** @infection-ignore-all */
$name = substr($name, 2);
}
return $name;
}
/**
* Sanitizes MySQL username
*
* * strips part behind null byte
*
* @param string $name User given username
*/
public static function sanitizeMySQLUser(string $name): string
{
$position = strpos($name, chr(0));
if ($position !== false) {
return substr($name, 0, $position);
}
return $name;
}
/**
* Safe unserializer wrapper
*
* It does not unserialize data containing objects
*
* @param string $data Data to unserialize
*/
public static function safeUnserialize(string $data): mixed
{
/* validate serialized data */
$length = strlen($data);
$depth = 0;
for ($i = 0; $i < $length; $i++) {
$value = $data[$i];
switch ($value) {
case '}':
/* end of array */
if ($depth <= 0) {
return null;
}
$depth--;
break;
case 's':
/* string */
// parse sting length
$strlen = (int) substr($data, $i + 2);
// string start
$i = strpos($data, ':', $i + 2);
if ($i === false) {
return null;
}
// skip string, quotes and ;
$i += 2 + $strlen + 1;
if ($data[$i] !== ';') {
return null;
}
break;
case 'b':
case 'i':
case 'd':
case 'N':
/* bool, integer or double */
// skip value to separator
$i = strpos($data, ';', $i);
if ($i === false) {
return null;
}
break;
case 'a':
/* array */
// find array start
$i = strpos($data, '{', $i);
if ($i === false) {
return null;
}
// remember nesting
$depth++;
break;
default:
/* any other elements are not wanted */
return null;
}
}
// check unterminated arrays
if ($depth > 0) {
return null;
}
// The manual parser above only permits scalars and plain arrays (s/b/i/d/N/a);
// any object token ('O:'/'C:') causes an early return null. Explicitly passing
// allowed_classes => false here adds defence-in-depth in case of parser edge
// cases and makes the intent clear to static analysis tools.
return unserialize($data, ['allowed_classes' => false]);
}
/**
* Sign the sql query using hmac using the session token
*
* @param string $sqlQuery The sql query
*/
public static function signSqlQuery(string $sqlQuery): string
{
$secret = $_SESSION[' HMAC_secret '] ?? '';
return hash_hmac('sha256', $sqlQuery, $secret . Config::getInstance()->config->blowfish_secret);
}
/**
* Check that the sql query has a valid hmac signature
*
* @param string $sqlQuery The sql query
* @param string $signature The Signature to check
*/
public static function checkSqlQuerySignature(string $sqlQuery, string $signature): bool
{
$secret = $_SESSION[' HMAC_secret '] ?? '';
$hmac = hash_hmac('sha256', $sqlQuery, $secret . Config::getInstance()->config->blowfish_secret);
return hash_equals($hmac, $signature);
}
public static function populateRequestWithEncryptedQueryParams(ServerRequest $request): ServerRequest
{
$queryParams = $request->getQueryParams();
$parsedBody = $request->getParsedBody();
unset($_GET['eq'], $_POST['eq'], $_REQUEST['eq']);
if (! isset($queryParams['eq']) && (! is_array($parsedBody) || ! isset($parsedBody['eq']))) {
return $request;
}
$encryptedQuery = '';
if (
is_array($parsedBody)
&& isset($parsedBody['eq'])
&& is_string($parsedBody['eq'])
&& $parsedBody['eq'] !== ''
) {
$encryptedQuery = $parsedBody['eq'];
unset($parsedBody['eq'], $queryParams['eq']);
} elseif (isset($queryParams['eq']) && is_string($queryParams['eq']) && $queryParams['eq'] !== '') {
$encryptedQuery = $queryParams['eq'];
unset($queryParams['eq']);
}
$decryptedQuery = null;
if ($encryptedQuery !== '') {
$decryptedQuery = Url::decryptQuery($encryptedQuery);
}
if ($decryptedQuery === null) {
$request = $request->withQueryParams($queryParams);
if (is_array($parsedBody)) {
return $request->withParsedBody($parsedBody);
}
return $request;
}
$urlQueryParams = (array) json_decode($decryptedQuery);
foreach ($urlQueryParams as $urlQueryParamKey => $urlQueryParamValue) {
if (is_array($parsedBody)) {
$parsedBody[$urlQueryParamKey] = $urlQueryParamValue;
$_POST[$urlQueryParamKey] = $urlQueryParamValue;
} else {
$queryParams[$urlQueryParamKey] = $urlQueryParamValue;
$_GET[$urlQueryParamKey] = $urlQueryParamValue;
}
$_REQUEST[$urlQueryParamKey] = $urlQueryParamValue;
}
$request = $request->withQueryParams($queryParams);
if (is_array($parsedBody)) {
return $request->withParsedBody($parsedBody);
}
return $request;
}
}