From 2bc9c9f6731bd614ca79eb3d173143ad7f6b7375 Mon Sep 17 00:00:00 2001
From: ppc <albie@ppc.moe>
Date: Wed, 15 Jan 2025 13:55:47 +0000
Subject: [PATCH] perform dfc checks before spad decryption

---
 amnet-native/lib/iccard.ts | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/amnet-native/lib/iccard.ts b/amnet-native/lib/iccard.ts
index a701b6d..516baa1 100644
--- a/amnet-native/lib/iccard.ts
+++ b/amnet-native/lib/iccard.ts
@@ -112,13 +112,22 @@ async function readAmusementICCardContents(idm: string): Promise<AmusementICCard
         return null;
     }
 
-    const accessCode = performDecrypt(new Uint8Array(response.slice(12, 28)));
     const dfcValue = response[37] | (response[36] << 8);
 
+    if (dfcValue in AmusementICVendor && dfcValue !== AmusementICVendor.Unknown) {
+        const accessCode = performDecrypt(new Uint8Array(response.slice(12, 28)));
+        return {
+            type: ICType.Amusement,
+            accessCode: [...accessCode.accessCodeBytes].map(x => x.toString(16).padStart(2, '0')).join(''),
+            vendor: dfcValue,
+            idm
+        };
+    }
+
     return {
         type: ICType.Amusement,
-        accessCode: [...accessCode.accessCodeBytes].map(x => x.toString(16).padStart(2, '0')).join(''),
-        vendor: dfcValue in AmusementICVendor ? dfcValue : AmusementICVendor.Unknown,
+        accessCode: icCard0008Number(idm),
+        vendor: AmusementICVendor.Unknown,
         idm
     };
 }