<?php
+/**
+ * @copyright Copyright (C) 2010-2022, the Friendica project
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
namespace Friendica\Util;
-use Friendica\Util\JsonLD;
-use Friendica\Util\DateTimeFormat;
-use Friendica\Protocol\ActivityPub;
+use Friendica\Core\Logger;
+use Friendica\Model\APContact;
+/**
+ * Implements JSON-LD signatures
+ *
+ * Ported from Osada: https://framagit.org/macgirvin/osada
+ */
class LDSignature
{
- public static function isSigned($data)
+ /**
+ * Checks if element 'signature' is found and not empty
+ *
+ * @param array $data
+ * @return bool
+ */
+ public static function isSigned(array $data): bool
{
return !empty($data['signature']);
}
- public static function getSigner($data)
+ /**
+ * Returns actor (signer) from given data
+ *
+ * @param array $data
+ * @return mixed Returns actor or false on error
+ */
+ public static function getSigner(array $data)
{
if (!self::isSigned($data)) {
return false;
}
-/*
- $creator = $data['signature']['creator'];
$actor = JsonLD::fetchElement($data, 'actor', 'id');
-
- $url = (strpos($creator, '#') ? substr($creator, 0, strpos($creator, '#')) : $creator);
-
- $profile = ActivityPub::fetchprofile($url);
- if (!empty($profile)) {
- logger('Taking key from creator ' . $creator, LOGGER_DEBUG);
- } elseif ($url != $actor) {
- $profile = ActivityPub::fetchprofile($actor);
- if (empty($profile)) {
- return false;
- }
- logger('Taking key from actor ' . $actor, LOGGER_DEBUG);
- }
-
-*/
- $actor = JsonLD::fetchElement($data, 'actor', 'id');
- if (empty($actor)) {
+ if (empty($actor) || !is_string($actor)) {
return false;
}
- $profile = ActivityPub::fetchprofile($actor);
+ $profile = APContact::getByURL($actor);
if (empty($profile['pubkey'])) {
return false;
}
$pubkey = $profile['pubkey'];
- $ohash = self::hash(self::signable_options($data['signature']));
- $dhash = self::hash(self::signable_data($data));
+ $ohash = self::hash(self::signableOptions($data['signature']));
+ $dhash = self::hash(self::signableData($data));
$x = Crypto::rsaVerify($ohash . $dhash, base64_decode($data['signature']['signatureValue']), $pubkey);
- logger('LD-verify: ' . intval($x));
+ Logger::notice('LD-verify', ['verified' => (int)$x, 'actor' => $profile['url']]);
if (empty($x)) {
return false;
}
}
- public static function sign($data, $owner)
+ /**
+ * Signs given data by owner's signature
+ *
+ * @param array $data Data to sign
+ * @param array $owner Owner information, like URL
+ * @return array Merged array of $data and signature
+ */
+ public static function sign(array $data, array $owner): array
{
$options = [
'type' => 'RsaSignature2017',
- 'nonce' => random_string(64),
+ 'nonce' => Strings::getRandomHex(64),
'creator' => $owner['url'] . '#main-key',
- 'created' => DateTimeFormat::utcNow(DateTimeFormat::ATOM)
+ 'created' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
];
- $ohash = self::hash(self::signable_options($options));
- $dhash = self::hash(self::signable_data($data));
+ $ohash = self::hash(self::signableOptions($options));
+ $dhash = self::hash(self::signableData($data));
$options['signatureValue'] = base64_encode(Crypto::rsaSign($ohash . $dhash, $owner['uprvkey']));
return array_merge($data, ['signature' => $options]);
}
-
- private static function signable_data($data)
+ /**
+ * Removes element 'signature' from array
+ *
+ * @param array $data
+ * @return array With no element 'signature'
+ */
+ private static function signableData(array $data): array
{
unset($data['signature']);
return $data;
}
-
- private static function signable_options($options)
+ /**
+ * Removes some elements and adds '@context' to it
+ *
+ * @param array $options
+ * @return array With some removed elements and added '@context' element
+ */
+ private static function signableOptions(array $options): array
{
$newopts = ['@context' => 'https://w3id.org/identity/v1'];
- if (!empty($options)) {
- foreach ($options as $k => $v) {
- if (!in_array($k, ['type', 'id', 'signatureValue'])) {
- $newopts[$k] = $v;
- }
- }
- }
- return $newopts;
+
+ unset($options['type']);
+ unset($options['id']);
+ unset($options['signatureValue']);
+
+ return array_merge($newopts, $options);
}
- private static function hash($obj)
+ /**
+ * Hashes normalized object
+ *
+ * @param ??? $obj
+ * @return string SHA256 hash
+ */
+ private static function hash($obj): string
{
return hash('sha256', JsonLD::normalize($obj));
}