From 492dee5e1aee0fbc2c5fb2d109a95beb0293adc4 Mon Sep 17 00:00:00 2001
From: djmaze <djmaze@djmaze.lan>
Date: Wed, 10 Nov 2021 09:14:57 +0100
Subject: [PATCH] Improved openssl_encrypt support

---
 .../libraries/RainLoop/Actions/UserAuth.php   |  4 +-
 .../libraries/RainLoop/Config/Application.php |  9 +++-
 .../0.0.0/app/libraries/snappymail/crypt.php  | 44 ++++++++++++++++---
 3 files changed, 48 insertions(+), 9 deletions(-)

diff --git a/snappymail/v/0.0.0/app/libraries/RainLoop/Actions/UserAuth.php b/snappymail/v/0.0.0/app/libraries/RainLoop/Actions/UserAuth.php
index 4a066560b..6c6df0b2b 100644
--- a/snappymail/v/0.0.0/app/libraries/RainLoop/Actions/UserAuth.php
+++ b/snappymail/v/0.0.0/app/libraries/RainLoop/Actions/UserAuth.php
@@ -234,9 +234,10 @@ trait UserAuth
 		$this->ClearSignMeData();
 
 		$uuid = \SnappyMail\UUID::generate();
+		\SnappyMail\Crypt::setCipher($this->Config()->Get('security', 'encrypt_cipher', ''));
 		$data = \SnappyMail\Crypt::EncryptRaw($oAccount);
 
-		if ($data['xxtea']) {
+		if ('xxtea' === $data[0]) {
 			static::SetSignMeTokenCookie(array(
 				'e' => $oAccount->Email(),
 				'u' => $uuid,
@@ -272,6 +273,7 @@ trait UserAuth
 				if (empty($sAuthToken)) {
 					return null;
 				}
+				\SnappyMail\Crypt::setCipher($this->Config()->Get('security', 'encrypt_cipher', ''));
 				if (!empty($aTokenData['s'])) {
 					$aAccountHash = \SnappyMail\Crypt::XxteaDecrypt($sAuthToken, \base64_decode($aTokenData['s']));
 				} else if (!empty($aTokenData['i'])) {
diff --git a/snappymail/v/0.0.0/app/libraries/RainLoop/Config/Application.php b/snappymail/v/0.0.0/app/libraries/RainLoop/Config/Application.php
index 544d9de1d..4d3c99a37 100644
--- a/snappymail/v/0.0.0/app/libraries/RainLoop/Config/Application.php
+++ b/snappymail/v/0.0.0/app/libraries/RainLoop/Config/Application.php
@@ -115,6 +115,12 @@ class Application extends \RainLoop\Config\AbstractConfig
 		}
 		$upload_max_filesize = $upload_max_filesize / 1024 / 1024;
 
+		$sCipher = 'aes-256-cbc-hmac-sha1';
+		$aCiphers = \SnappyMail\Crypt::listCiphers();
+		if (!\in_array($sCipher, $aCiphers)) {
+			$sCipher = $aCiphers[\array_rand($aCiphers)];
+		}
+
 		return array(
 
 			'webmail' => array(
@@ -174,7 +180,8 @@ class Application extends \RainLoop\Config\AbstractConfig
 				'hide_x_mailer_header'       => array(true),
 				'admin_panel_host'           => array(''),
 				'admin_panel_key'            => array('admin'),
-				'content_security_policy'    => array('')
+				'content_security_policy'    => array(''),
+				'encrypt_cipher'             => array($sCipher)
 			),
 
 			'ssl' => array(
diff --git a/snappymail/v/0.0.0/app/libraries/snappymail/crypt.php b/snappymail/v/0.0.0/app/libraries/snappymail/crypt.php
index 7c5d66c1c..6565fe74a 100644
--- a/snappymail/v/0.0.0/app/libraries/snappymail/crypt.php
+++ b/snappymail/v/0.0.0/app/libraries/snappymail/crypt.php
@@ -7,7 +7,34 @@ abstract class Crypt
 	/**
 	 * Or use 'aes-256-xts' ?
 	 */
-	const CIPHER = 'aes-256-cbc-hmac-sha1';
+	protected static $cipher = 'aes-256-cbc-hmac-sha1';
+
+	public static function listCiphers() : array
+	{
+		$list = array();
+		if (\function_exists('openssl_get_cipher_methods')) {
+			$list = \openssl_get_cipher_methods();
+			$list = \array_diff($list, \array_map('strtoupper',$list));
+			$list = \array_filter($list, function($v){
+				// DES/ECB/bf/rc insecure, GCM/CCM not supported
+				return !\preg_match('/(^(des|bf|rc))|-(ecb|gcm|ccm)/i', $v);
+			});
+			\natcasesort($list);
+		}
+		return $list;
+	}
+
+	public static function setCipher(string $cipher) : bool
+	{
+		if ($cipher) {
+			$aCiphers = static::listCiphers();
+			if (\in_array($cipher, $aCiphers)) {
+				static::$cipher = $cipher;
+				return true;
+			}
+		}
+		return false;
+	}
 
 	private static function Passphrase() : string
 	{
@@ -43,16 +70,16 @@ abstract class Crypt
 
 	public static function EncryptRaw($data) : array
 	{
-		if (\is_callable('openssl_encrypt')) {
-			$iv = \random_bytes(\openssl_cipher_iv_length(static::CIPHER));
+		if (static::$cipher && \is_callable('openssl_encrypt')) {
+			$iv = \random_bytes(\openssl_cipher_iv_length(static::$cipher));
 			$data = \openssl_encrypt(
 				\json_encode($data),
-				static::CIPHER,
+				static::$cipher,
 				static::Passphrase(),
 				OPENSSL_RAW_DATA,
 				$iv
 			);
-			return [static::CIPHER, $iv, $data];
+			return [static::$cipher, $iv, $data];
 		}
 
 		$salt = \random_bytes(16);
@@ -61,12 +88,15 @@ abstract class Crypt
 
 	public static function OpenSSLDecrypt(string $data, string $iv)
 	{
-		if (!$data || !$iv || !\is_callable('openssl_decrypt')) {
+		if (!$data || !$iv) {
 			return null;
 		}
+		if (!static::$cipher || !\is_callable('openssl_decrypt')) {
+			return static::XxteaDecrypt($data, $iv);
+		}
 		return \json_decode(\openssl_decrypt(
 			$data,
-			static::CIPHER,
+			static::$cipher,
 			static::Passphrase(),
 			OPENSSL_RAW_DATA,
 			$iv