From 3ba4baa2b3075ee5213efcda8cc3c029d1426283 Mon Sep 17 00:00:00 2001
From: Kelvin Mo <kmo@users.sourceforge.net>
Date: Sat, 6 Jul 2024 12:40:05 +1000
Subject: [PATCH] Fix issue with null $alg in constructor

---
 src/SimpleJWT/Crypt/KeyManagement/AESGCMKeyWrap.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/SimpleJWT/Crypt/KeyManagement/AESGCMKeyWrap.php b/src/SimpleJWT/Crypt/KeyManagement/AESGCMKeyWrap.php
index 6de8d26..f5fa7d8 100644
--- a/src/SimpleJWT/Crypt/KeyManagement/AESGCMKeyWrap.php
+++ b/src/SimpleJWT/Crypt/KeyManagement/AESGCMKeyWrap.php
@@ -52,7 +52,7 @@ class AESGCMKeyWrap extends BaseAlgorithm implements KeyEncryptionAlgorithm {
     private $aesgcm;
 
     public function __construct(?string $alg) {
-        $this->aesgcm = new AESGCM(substr($alg, 0, -2));
+        $this->aesgcm = new AESGCM(($alg == null) ? null : substr($alg, 0, -2));
         parent::__construct($alg);
     }