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-rw-r--r--apps/encryption/lib/Crypto/Crypt.php422
1 files changed, 253 insertions, 169 deletions
diff --git a/apps/encryption/lib/Crypto/Crypt.php b/apps/encryption/lib/Crypto/Crypt.php
index 93120068c6a..463ca4e22bb 100644
--- a/apps/encryption/lib/Crypto/Crypt.php
+++ b/apps/encryption/lib/Crypto/Crypt.php
@@ -1,32 +1,9 @@
<?php
+
/**
- * @copyright Copyright (c) 2016, ownCloud, Inc.
- *
- * @author Bjoern Schiessle <bjoern@schiessle.org>
- * @author Björn Schießle <bjoern@schiessle.org>
- * @author Christoph Wurst <christoph@winzerhof-wurst.at>
- * @author Clark Tomlinson <fallen013@gmail.com>
- * @author Joas Schilling <coding@schilljs.com>
- * @author Lukas Reschke <lukas@statuscode.ch>
- * @author Morris Jobke <hey@morrisjobke.de>
- * @author Roeland Jago Douma <roeland@famdouma.nl>
- * @author Stefan Weiberg <sweiberg@suse.com>
- * @author Thomas Müller <thomas.mueller@tmit.eu>
- *
- * @license AGPL-3.0
- *
- * This code is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License, version 3,
- * as published by the Free Software Foundation.
- *
- * 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, version 3,
- * along with this program. If not, see <http://www.gnu.org/licenses/>
- *
+ * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
+ * SPDX-License-Identifier: AGPL-3.0-only
*/
namespace OCA\Encryption\Crypto;
@@ -38,8 +15,9 @@ use OCA\Encryption\Exceptions\MultiKeyEncryptException;
use OCP\Encryption\Exceptions\GenericEncryptionException;
use OCP\IConfig;
use OCP\IL10N;
-use OCP\ILogger;
use OCP\IUserSession;
+use phpseclib\Crypt\RC4;
+use Psr\Log\LoggerInterface;
/**
* Class Crypt provides the encryption implementation of the default Nextcloud
@@ -67,9 +45,9 @@ class Crypt {
// default cipher from old Nextcloud versions
public const LEGACY_CIPHER = 'AES-128-CFB';
- public const SUPPORTED_KEY_FORMATS = ['hash', 'password'];
+ public const SUPPORTED_KEY_FORMATS = ['hash2', 'hash', 'password'];
// one out of SUPPORTED_KEY_FORMATS
- public const DEFAULT_KEY_FORMAT = 'hash';
+ public const DEFAULT_KEY_FORMAT = 'hash2';
// default key format, old Nextcloud version encrypted the private key directly
// with the user password
public const LEGACY_KEY_FORMAT = 'password';
@@ -77,53 +55,45 @@ class Crypt {
public const HEADER_START = 'HBEGIN';
public const HEADER_END = 'HEND';
- /** @var ILogger */
- private $logger;
-
- /** @var string */
- private $user;
-
- /** @var IConfig */
- private $config;
+ // default encoding format, old Nextcloud versions used base64
+ public const BINARY_ENCODING_FORMAT = 'binary';
- /** @var IL10N */
- private $l;
+ private string $user;
- /** @var string|null */
- private $currentCipher;
+ private ?string $currentCipher = null;
- /** @var bool */
- private $supportLegacy;
+ private bool $supportLegacy;
/**
- * @param ILogger $logger
- * @param IUserSession $userSession
- * @param IConfig $config
- * @param IL10N $l
+ * Use the legacy base64 encoding instead of the more space-efficient binary encoding.
*/
- public function __construct(ILogger $logger, IUserSession $userSession, IConfig $config, IL10N $l) {
- $this->logger = $logger;
- $this->user = $userSession && $userSession->isLoggedIn() ? $userSession->getUser()->getUID() : '"no user given"';
- $this->config = $config;
- $this->l = $l;
+ private bool $useLegacyBase64Encoding;
+
+ public function __construct(
+ private LoggerInterface $logger,
+ IUserSession $userSession,
+ private IConfig $config,
+ private IL10N $l,
+ ) {
+ $this->user = $userSession->isLoggedIn() ? $userSession->getUser()->getUID() : '"no user given"';
$this->supportLegacy = $this->config->getSystemValueBool('encryption.legacy_format_support', false);
+ $this->useLegacyBase64Encoding = $this->config->getSystemValueBool('encryption.use_legacy_base64_encoding', false);
}
/**
* create new private/public key-pair for user
*
- * @return array|bool
+ * @return array{publicKey: string, privateKey: string}|false
*/
public function createKeyPair() {
- $log = $this->logger;
$res = $this->getOpenSSLPKey();
if (!$res) {
- $log->error("Encryption Library couldn't generate users key-pair for {$this->user}",
+ $this->logger->error("Encryption Library couldn't generate users key-pair for {$this->user}",
['app' => 'encryption']);
if (openssl_error_string()) {
- $log->error('Encryption library openssl_pkey_new() fails: ' . openssl_error_string(),
+ $this->logger->error('Encryption library openssl_pkey_new() fails: ' . openssl_error_string(),
['app' => 'encryption']);
}
} elseif (openssl_pkey_export($res,
@@ -138,10 +108,10 @@ class Crypt {
'privateKey' => $privateKey
];
}
- $log->error('Encryption library couldn\'t export users private key, please check your servers OpenSSL configuration.' . $this->user,
+ $this->logger->error('Encryption library couldn\'t export users private key, please check your servers OpenSSL configuration.' . $this->user,
['app' => 'encryption']);
if (openssl_error_string()) {
- $log->error('Encryption Library:' . openssl_error_string(),
+ $this->logger->error('Encryption Library:' . openssl_error_string(),
['app' => 'encryption']);
}
@@ -151,19 +121,14 @@ class Crypt {
/**
* Generates a new private key
*
- * @return resource
+ * @return \OpenSSLAsymmetricKey|false
*/
public function getOpenSSLPKey() {
$config = $this->getOpenSSLConfig();
return openssl_pkey_new($config);
}
- /**
- * get openSSL Config
- *
- * @return array
- */
- private function getOpenSSLConfig() {
+ private function getOpenSSLConfig(): array {
$config = ['private_key_bits' => 4096];
$config = array_merge(
$config,
@@ -173,14 +138,9 @@ class Crypt {
}
/**
- * @param string $plainContent
- * @param string $passPhrase
- * @param int $version
- * @param int $position
- * @return false|string
* @throws EncryptionFailedException
*/
- public function symmetricEncryptFileContent($plainContent, $passPhrase, $version, $position) {
+ public function symmetricEncryptFileContent(string $plainContent, string $passPhrase, int $version, string $position): string|false {
if (!$plainContent) {
$this->logger->error('Encryption Library, symmetrical encryption failed no content given',
['app' => 'encryption']);
@@ -195,7 +155,7 @@ class Crypt {
$this->getCipher());
// Create a signature based on the key as well as the current version
- $sig = $this->createSignature($encryptedContent, $passPhrase.'_'.$version.'_'.$position);
+ $sig = $this->createSignature($encryptedContent, $passPhrase . '_' . $version . '_' . $position);
// combine content to encrypt the IV identifier and actual IV
$catFile = $this->concatIV($encryptedContent, $iv);
@@ -215,29 +175,28 @@ class Crypt {
throw new \InvalidArgumentException('key format "' . $keyFormat . '" is not supported');
}
- $cipher = $this->getCipher();
-
$header = self::HEADER_START
- . ':cipher:' . $cipher
- . ':keyFormat:' . $keyFormat
- . ':' . self::HEADER_END;
+ . ':cipher:' . $this->getCipher()
+ . ':keyFormat:' . $keyFormat;
+
+ if ($this->useLegacyBase64Encoding !== true) {
+ $header .= ':encoding:' . self::BINARY_ENCODING_FORMAT;
+ }
+
+ $header .= ':' . self::HEADER_END;
return $header;
}
/**
- * @param string $plainContent
- * @param string $iv
- * @param string $passPhrase
- * @param string $cipher
- * @return string
* @throws EncryptionFailedException
*/
- private function encrypt($plainContent, $iv, $passPhrase = '', $cipher = self::DEFAULT_CIPHER) {
+ private function encrypt(string $plainContent, string $iv, string $passPhrase = '', string $cipher = self::DEFAULT_CIPHER): string {
+ $options = $this->useLegacyBase64Encoding ? 0 : OPENSSL_RAW_DATA;
$encryptedContent = openssl_encrypt($plainContent,
$cipher,
$passPhrase,
- 0,
+ $options,
$iv);
if (!$encryptedContent) {
@@ -253,16 +212,14 @@ class Crypt {
/**
* return cipher either from config.php or the default cipher defined in
* this class
- *
- * @return string
*/
- private function getCachedCipher() {
+ private function getCachedCipher(): string {
if (isset($this->currentCipher)) {
return $this->currentCipher;
}
// Get cipher either from config.php or the default cipher defined in this class
- $cipher = $this->config->getSystemValue('cipher', self::DEFAULT_CIPHER);
+ $cipher = $this->config->getSystemValueString('cipher', self::DEFAULT_CIPHER);
if (!isset(self::SUPPORTED_CIPHERS_AND_KEY_SIZE[$cipher])) {
$this->logger->warning(
sprintf(
@@ -303,8 +260,8 @@ class Crypt {
throw new \InvalidArgumentException(
sprintf(
- 'Unsupported cipher (%s) defined.',
- $cipher
+ 'Unsupported cipher (%s) defined.',
+ $cipher
)
);
}
@@ -322,21 +279,11 @@ class Crypt {
return self::LEGACY_CIPHER;
}
- /**
- * @param string $encryptedContent
- * @param string $iv
- * @return string
- */
- private function concatIV($encryptedContent, $iv) {
+ private function concatIV(string $encryptedContent, string $iv): string {
return $encryptedContent . '00iv00' . $iv;
}
- /**
- * @param string $encryptedContent
- * @param string $signature
- * @return string
- */
- private function concatSig($encryptedContent, $signature) {
+ private function concatSig(string $encryptedContent, string $signature): string {
return $encryptedContent . '00sig00' . $signature;
}
@@ -344,38 +291,30 @@ class Crypt {
* Note: This is _NOT_ a padding used for encryption purposes. It is solely
* used to achieve the PHP stream size. It has _NOTHING_ to do with the
* encrypted content and is not used in any crypto primitive.
- *
- * @param string $data
- * @return string
*/
- private function addPadding($data) {
+ private function addPadding(string $data): string {
return $data . 'xxx';
}
/**
* generate password hash used to encrypt the users private key
*
- * @param string $password
- * @param string $cipher
* @param string $uid only used for user keys
- * @return string
*/
- protected function generatePasswordHash($password, $cipher, $uid = '') {
+ protected function generatePasswordHash(string $password, string $cipher, string $uid = '', int $iterations = 600000): string {
$instanceId = $this->config->getSystemValue('instanceid');
$instanceSecret = $this->config->getSystemValue('secret');
$salt = hash('sha256', $uid . $instanceId . $instanceSecret, true);
$keySize = $this->getKeySize($cipher);
- $hash = hash_pbkdf2(
+ return hash_pbkdf2(
'sha256',
$password,
$salt,
- 100000,
+ $iterations,
$keySize,
true
);
-
- return $hash;
}
/**
@@ -393,7 +332,7 @@ class Crypt {
$privateKey,
$hash,
0,
- 0
+ '0'
);
return $encryptedKey;
@@ -420,10 +359,14 @@ class Crypt {
$keyFormat = self::LEGACY_KEY_FORMAT;
}
- if ($keyFormat === self::DEFAULT_KEY_FORMAT) {
- $password = $this->generatePasswordHash($password, $cipher, $uid);
+ if ($keyFormat === 'hash') {
+ $password = $this->generatePasswordHash($password, $cipher, $uid, 100000);
+ } elseif ($keyFormat === 'hash2') {
+ $password = $this->generatePasswordHash($password, $cipher, $uid, 600000);
}
+ $binaryEncoding = isset($header['encoding']) && $header['encoding'] === self::BINARY_ENCODING_FORMAT;
+
// If we found a header we need to remove it from the key we want to decrypt
if (!empty($header)) {
$privateKey = substr($privateKey,
@@ -435,7 +378,9 @@ class Crypt {
$privateKey,
$password,
$cipher,
- 0
+ 0,
+ 0,
+ $binaryEncoding
);
if ($this->isValidPrivateKey($plainKey) === false) {
@@ -453,8 +398,7 @@ class Crypt {
*/
protected function isValidPrivateKey($plainKey) {
$res = openssl_get_privatekey($plainKey);
- // TODO: remove resource check one php7.4 is not longer supported
- if (is_resource($res) || (is_object($res) && get_class($res) === 'OpenSSLAsymmetricKey')) {
+ if (is_object($res) && get_class($res) === 'OpenSSLAsymmetricKey') {
$sslInfo = openssl_pkey_get_details($res);
if (isset($sslInfo['key'])) {
return true;
@@ -470,10 +414,11 @@ class Crypt {
* @param string $cipher
* @param int $version
* @param int|string $position
+ * @param boolean $binaryEncoding
* @return string
* @throws DecryptionFailedException
*/
- public function symmetricDecryptFileContent($keyFileContents, $passPhrase, $cipher = self::DEFAULT_CIPHER, $version = 0, $position = 0) {
+ public function symmetricDecryptFileContent($keyFileContents, $passPhrase, $cipher = self::DEFAULT_CIPHER, $version = 0, $position = 0, bool $binaryEncoding = false) {
if ($keyFileContents == '') {
return '';
}
@@ -493,51 +438,43 @@ class Crypt {
return $this->decrypt($catFile['encrypted'],
$catFile['iv'],
$passPhrase,
- $cipher);
+ $cipher,
+ $binaryEncoding);
}
/**
* check for valid signature
*
- * @param string $data
- * @param string $passPhrase
- * @param string $expectedSignature
* @throws GenericEncryptionException
*/
- private function checkSignature($data, $passPhrase, $expectedSignature) {
- $enforceSignature = !$this->config->getSystemValue('encryption_skip_signature_check', false);
+ private function checkSignature(string $data, string $passPhrase, string $expectedSignature): void {
+ $enforceSignature = !$this->config->getSystemValueBool('encryption_skip_signature_check', false);
$signature = $this->createSignature($data, $passPhrase);
$isCorrectHash = hash_equals($expectedSignature, $signature);
- if (!$isCorrectHash && $enforceSignature) {
- throw new GenericEncryptionException('Bad Signature', $this->l->t('Bad Signature'));
- } elseif (!$isCorrectHash && !$enforceSignature) {
- $this->logger->info("Signature check skipped", ['app' => 'encryption']);
+ if (!$isCorrectHash) {
+ if ($enforceSignature) {
+ throw new GenericEncryptionException('Bad Signature', $this->l->t('Bad Signature'));
+ } else {
+ $this->logger->info('Signature check skipped', ['app' => 'encryption']);
+ }
}
}
/**
* create signature
- *
- * @param string $data
- * @param string $passPhrase
- * @return string
*/
- private function createSignature($data, $passPhrase) {
+ private function createSignature(string $data, string $passPhrase): string {
$passPhrase = hash('sha512', $passPhrase . 'a', true);
return hash_hmac('sha256', $data, $passPhrase);
}
/**
- * remove padding
- *
- * @param string $padded
* @param bool $hasSignature did the block contain a signature, in this case we use a different padding
- * @return string|false
*/
- private function removePadding($padded, $hasSignature = false) {
+ private function removePadding(string $padded, bool $hasSignature = false): string|false {
if ($hasSignature === false && substr($padded, -2) === 'xx') {
return substr($padded, 0, -2);
} elseif ($hasSignature === true && substr($padded, -3) === 'xxx') {
@@ -550,12 +487,8 @@ class Crypt {
* split meta data from encrypted file
* Note: for now, we assume that the meta data always start with the iv
* followed by the signature, if available
- *
- * @param string $catFile
- * @param string $cipher
- * @return array
*/
- private function splitMetaData($catFile, $cipher) {
+ private function splitMetaData(string $catFile, string $cipher): array {
if ($this->hasSignature($catFile, $cipher)) {
$catFile = $this->removePadding($catFile, true);
$meta = substr($catFile, -93);
@@ -580,13 +513,10 @@ class Crypt {
/**
* check if encrypted block is signed
*
- * @param string $catFile
- * @param string $cipher
- * @return bool
* @throws GenericEncryptionException
*/
- private function hasSignature($catFile, $cipher) {
- $skipSignatureCheck = $this->config->getSystemValue('encryption_skip_signature_check', false);
+ private function hasSignature(string $catFile, string $cipher): bool {
+ $skipSignatureCheck = $this->config->getSystemValueBool('encryption_skip_signature_check', false);
$meta = substr($catFile, -93);
$signaturePosition = strpos($meta, '00sig00');
@@ -606,18 +536,14 @@ class Crypt {
/**
- * @param string $encryptedContent
- * @param string $iv
- * @param string $passPhrase
- * @param string $cipher
- * @return string
* @throws DecryptionFailedException
*/
- private function decrypt($encryptedContent, $iv, $passPhrase = '', $cipher = self::DEFAULT_CIPHER) {
+ private function decrypt(string $encryptedContent, string $iv, string $passPhrase = '', string $cipher = self::DEFAULT_CIPHER, bool $binaryEncoding = false): string {
+ $options = $binaryEncoding === true ? OPENSSL_RAW_DATA : 0;
$plainContent = openssl_decrypt($encryptedContent,
$cipher,
$passPhrase,
- 0,
+ $options,
$iv);
if ($plainContent) {
@@ -656,10 +582,9 @@ class Crypt {
/**
* generate initialization vector
*
- * @return string
* @throws GenericEncryptionException
*/
- private function generateIv() {
+ private function generateIv(): string {
return random_bytes(16);
}
@@ -675,18 +600,31 @@ class Crypt {
}
/**
- * @param $encKeyFile
- * @param $shareKey
- * @param $privateKey
- * @return string
+ * @param \OpenSSLAsymmetricKey|\OpenSSLCertificate|array|string $privateKey
* @throws MultiKeyDecryptException
*/
- public function multiKeyDecrypt($encKeyFile, $shareKey, $privateKey) {
+ public function multiKeyDecrypt(string $shareKey, $privateKey): string {
+ $plainContent = '';
+
+ // decrypt the intermediate key with RSA
+ if (openssl_private_decrypt($shareKey, $intermediate, $privateKey, OPENSSL_PKCS1_OAEP_PADDING)) {
+ return $intermediate;
+ } else {
+ throw new MultiKeyDecryptException('multikeydecrypt with share key failed:' . openssl_error_string());
+ }
+ }
+
+ /**
+ * @param \OpenSSLAsymmetricKey|\OpenSSLCertificate|array|string $privateKey
+ * @throws MultiKeyDecryptException
+ */
+ public function multiKeyDecryptLegacy(string $encKeyFile, string $shareKey, $privateKey): string {
if (!$encKeyFile) {
throw new MultiKeyDecryptException('Cannot multikey decrypt empty plain content');
}
- if (openssl_open($encKeyFile, $plainContent, $shareKey, $privateKey, 'RC4')) {
+ $plainContent = '';
+ if ($this->opensslOpen($encKeyFile, $plainContent, $shareKey, $privateKey, 'RC4')) {
return $plainContent;
} else {
throw new MultiKeyDecryptException('multikeydecrypt with share key failed:' . openssl_error_string());
@@ -694,12 +632,55 @@ class Crypt {
}
/**
+ * @param array<string,\OpenSSLAsymmetricKey|\OpenSSLCertificate|array|string> $keyFiles
+ * @throws MultiKeyEncryptException
+ */
+ public function multiKeyEncrypt(string $plainContent, array $keyFiles): array {
+ if (empty($plainContent)) {
+ throw new MultiKeyEncryptException('Cannot multikeyencrypt empty plain content');
+ }
+
+ // Set empty vars to be set by openssl by reference
+ $shareKeys = [];
+ $mappedShareKeys = [];
+
+ // make sure that there is at least one public key to use
+ if (count($keyFiles) >= 1) {
+ // prepare the encrypted keys
+ $shareKeys = [];
+
+ // iterate over the public keys and encrypt the intermediate
+ // for each of them with RSA
+ foreach ($keyFiles as $tmp_key) {
+ if (openssl_public_encrypt($plainContent, $tmp_output, $tmp_key, OPENSSL_PKCS1_OAEP_PADDING)) {
+ $shareKeys[] = $tmp_output;
+ }
+ }
+
+ // set the result if everything worked fine
+ if (count($keyFiles) === count($shareKeys)) {
+ $i = 0;
+
+ // Ensure each shareKey is labelled with its corresponding key id
+ foreach ($keyFiles as $userId => $publicKey) {
+ $mappedShareKeys[$userId] = $shareKeys[$i];
+ $i++;
+ }
+
+ return $mappedShareKeys;
+ }
+ }
+ throw new MultiKeyEncryptException('multikeyencryption failed ' . openssl_error_string());
+ }
+
+ /**
* @param string $plainContent
* @param array $keyFiles
* @return array
* @throws MultiKeyEncryptException
+ * @deprecated 27.0.0 use multiKeyEncrypt
*/
- public function multiKeyEncrypt($plainContent, array $keyFiles) {
+ public function multiKeyEncryptLegacy($plainContent, array $keyFiles) {
// openssl_seal returns false without errors if plaincontent is empty
// so trigger our own error
if (empty($plainContent)) {
@@ -711,7 +692,7 @@ class Crypt {
$shareKeys = [];
$mappedShareKeys = [];
- if (openssl_seal($plainContent, $sealed, $shareKeys, $keyFiles, 'RC4')) {
+ if ($this->opensslSeal($plainContent, $sealed, $shareKeys, $keyFiles, 'RC4')) {
$i = 0;
// Ensure each shareKey is labelled with its corresponding key id
@@ -728,4 +709,107 @@ class Crypt {
throw new MultiKeyEncryptException('multikeyencryption failed ' . openssl_error_string());
}
}
+
+ /**
+ * returns the value of $useLegacyBase64Encoding
+ *
+ * @return bool
+ */
+ public function useLegacyBase64Encoding(): bool {
+ return $this->useLegacyBase64Encoding;
+ }
+
+ /**
+ * Uses phpseclib RC4 implementation
+ */
+ private function rc4Decrypt(string $data, string $secret): string {
+ $rc4 = new RC4();
+ /** @psalm-suppress InternalMethod */
+ $rc4->setKey($secret);
+
+ return $rc4->decrypt($data);
+ }
+
+ /**
+ * Uses phpseclib RC4 implementation
+ */
+ private function rc4Encrypt(string $data, string $secret): string {
+ $rc4 = new RC4();
+ /** @psalm-suppress InternalMethod */
+ $rc4->setKey($secret);
+
+ return $rc4->encrypt($data);
+ }
+
+ /**
+ * Custom implementation of openssl_open()
+ *
+ * @param \OpenSSLAsymmetricKey|\OpenSSLCertificate|array|string $private_key
+ * @throws DecryptionFailedException
+ */
+ private function opensslOpen(string $data, string &$output, string $encrypted_key, $private_key, string $cipher_algo): bool {
+ $result = false;
+
+ // check if RC4 is used
+ if (strcasecmp($cipher_algo, 'rc4') === 0) {
+ // decrypt the intermediate key with RSA
+ if (openssl_private_decrypt($encrypted_key, $intermediate, $private_key, OPENSSL_PKCS1_PADDING)) {
+ // decrypt the file key with the intermediate key
+ // using our own RC4 implementation
+ $output = $this->rc4Decrypt($data, $intermediate);
+ $result = (strlen($output) === strlen($data));
+ }
+ } else {
+ throw new DecryptionFailedException('Unsupported cipher ' . $cipher_algo);
+ }
+
+ return $result;
+ }
+
+ /**
+ * Custom implementation of openssl_seal()
+ *
+ * @deprecated 27.0.0 use multiKeyEncrypt
+ * @throws EncryptionFailedException
+ */
+ private function opensslSeal(string $data, string &$sealed_data, array &$encrypted_keys, array $public_key, string $cipher_algo): int|false {
+ $result = false;
+
+ // check if RC4 is used
+ if (strcasecmp($cipher_algo, 'rc4') === 0) {
+ // make sure that there is at least one public key to use
+ if (count($public_key) >= 1) {
+ // generate the intermediate key
+ $intermediate = openssl_random_pseudo_bytes(16, $strong_result);
+
+ // check if we got strong random data
+ if ($strong_result) {
+ // encrypt the file key with the intermediate key
+ // using our own RC4 implementation
+ $sealed_data = $this->rc4Encrypt($data, $intermediate);
+ if (strlen($sealed_data) === strlen($data)) {
+ // prepare the encrypted keys
+ $encrypted_keys = [];
+
+ // iterate over the public keys and encrypt the intermediate
+ // for each of them with RSA
+ foreach ($public_key as $tmp_key) {
+ if (openssl_public_encrypt($intermediate, $tmp_output, $tmp_key, OPENSSL_PKCS1_PADDING)) {
+ $encrypted_keys[] = $tmp_output;
+ }
+ }
+
+ // set the result if everything worked fine
+ if (count($public_key) === count($encrypted_keys)) {
+ $result = strlen($sealed_data);
+ }
+ }
+ }
+ }
+ } else {
+ throw new EncryptionFailedException('Unsupported cipher ' . $cipher_algo);
+ }
+
+ return $result;
+ }
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-08-14 21:06:18 +0000