<?php
/*
* This file is part of Composer.
*
* (c) Nils Adermann <naderman@naderman.de>
* Jordi Boggiano <j.boggiano@seld.be>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Composer\Util;
use Composer\CaBundle\CaBundle;
/**
* @author Chris Smith <chris@cs278.org>
*/
final class TlsHelper
{
/**
* Match hostname against a certificate.
*
* @param mixed $certificate X.509 certificate
* @param string $hostname Hostname in the URL
* @param string $cn Set to the common name of the certificate iff match found
*
* @return bool
*/
public static function checkCertificateHost($certificate, $hostname, &$cn = null)
{
$names = self::getCertificateNames($certificate);
if (empty($names)) {
return false;
}
$combinedNames = array_merge($names['san'], array($names['cn']));
$hostname = strtolower($hostname);
foreach ($combinedNames as $certName) {
$matcher = self::certNameMatcher($certName);
if ($matcher && $matcher($hostname)) {
$cn = $names['cn'];
return true;
}
}
return false;
}
/**
* Extract DNS names out of an X.509 certificate.
*
* @param mixed $certificate X.509 certificate
*
* @return array|null
*/
public static function getCertificateNames($certificate)
{
if (is_array($certificate)) {
$info = $certificate;
} elseif (CaBundle::isOpensslParseSafe()) {
$info = openssl_x509_parse($certificate, false);
}
if (!isset($info['subject']['commonName'])) {
return null;
}
$commonName = strtolower($info['subject']['commonName']);
$subjectAltNames = array();
if (isset($info['extensions']['subjectAltName'])) {
$subjectAltNames = preg_split('{\s*,\s*}', $info['extensions']['subjectAltName']);
$subjectAltNames = array_filter(array_map(function ($name) {
if (0 === strpos($name, 'DNS:')) {
return strtolower(ltrim(substr($name, 4)));
}
return null;
}, $subjectAltNames));
$subjectAltNames = array_values($subjectAltNames);
}
return array(
'cn' => $commonName,
'san' => $subjectAltNames,
);
}
/**
* Get the certificate pin.
*
* By Kevin McArthur of StormTide Digital Studios Inc.
* @KevinSMcArthur / https://github.com/StormTide
*
* See http://tools.ietf.org/html/draft-ietf-websec-key-pinning-02
*
* This method was adapted from Sslurp.
* https://github.com/EvanDotPro/Sslurp
*
* (c) Evan Coury <me@evancoury.com>
*
* For the full copyright and license information, please see below:
*
* Copyright (c) 2013, Evan Coury
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
public static function getCertificateFingerprint($certificate)
{
$pubkeydetails = openssl_pkey_get_details(openssl_get_publickey($certificate));
$pubkeypem = $pubkeydetails['key'];
//Convert PEM to DER before SHA1'ing
$start = '-----BEGIN PUBLIC KEY-----';
$end = '-----END PUBLIC KEY-----';
$pemtrim = substr($pubkeypem, strpos($pubkeypem, $start) + strlen($start), (strlen($pubkeypem) - strpos($pubkeypem, $end)) * (-1));
$der = base64_decode($pemtrim);
return sha1($der);
}
/**
* Test if it is safe to use the PHP function openssl_x509_parse().
*
* This checks if OpenSSL extensions is vulnerable to remote code execution
* via the exploit documented as CVE-2013-6420.
*
* @return bool
*/
public static function isOpensslParseSafe()
{
return CaBundle::isOpensslParseSafe();
}
/**
* Convert certificate name into matching function.
*
* @param string $certName CN/SAN
*
* @return callable|void
*/
private static function certNameMatcher($certName)
{
$wildcards = substr_count($certName, '*');
if (0 === $wildcards) {
// Literal match.
return function ($hostname) use ($certName) {
return $hostname === $certName;
};
}
if (1 === $wildcards) {
$components = explode('.', $certName);
if (3 > count($components)) {
// Must have 3+ components
return;
}
$firstComponent = $components[0];
// Wildcard must be the last character.
if ('*' !== $firstComponent[strlen($firstComponent) - 1]) {
return;
}
$wildcardRegex = preg_quote($certName);
$wildcardRegex = str_replace('\\*', '[a-z0-9-]+', $wildcardRegex);
$wildcardRegex = "{^{$wildcardRegex}$}";
return function ($hostname) use ($wildcardRegex) {
return 1 === preg_match($wildcardRegex, $hostname);
};
}
}
}