From bebc4c46edc49503c900823efe3b595ae2578abb Mon Sep 17 00:00:00 2001
From: PackageInstaller <yjzyl9008@gmail.com>
Date: Sat, 11 Oct 2025 21:05:19 +0800
Subject: [PATCH] update decrypt.py

---
 decrypt.py | 55 ++++++++++++++++++++++++++++++------------------------
 1 file changed, 31 insertions(+), 24 deletions(-)

diff --git a/decrypt.py b/decrypt.py
index 057461a..7dceeb8 100644
--- a/decrypt.py
+++ b/decrypt.py
@@ -1,35 +1,42 @@
 import os
 import multiprocessing
 
-def xorhead(data):
-    result = bytearray(data)
-    for i in range(0, 32):
-        result[i] ^= (len(data) + i).to_bytes(4, 'big')[3]
-    return bytes(result)
+def get_ab_encrypt_key(md5_name: str) -> int:
+    sv = 0
+    for char in md5_name:
+        sv += ord(char)
+    sv &= 0xFF
 
-def xordata(data):
-    result = bytearray(data)
-    for i in range(0, len(data) - 32):
-        result[i + 32] ^= (i + 32).to_bytes(4, 'big')[3]
-        if i + 32 >= 4096:
-            return bytes(result)
-    return bytes(result)
+    if (sv & 1) != 0:
+        key = sv + 4
+    else:
+        key = sv + 2
+    return key & 0xFF
 
-def decrypt(file):
-    print(file)
-    path = "bundles/" + file
-    data = open(path,'rb').read()
-    with open("bundles-decrypt/" + file, "wb") as f:
-        f.write(xordata(xorhead(data)))
+def xor_decrypt_data(data: bytes, key: int) -> bytes:
+    dec = bytearray(data)
+    for i in range(len(dec)):
+        dec[i] ^= key
+    return bytes(dec)
+
+
+def decrypt(file: str):
+    print(f"{file}")
+    key_str, _ = os.path.splitext(file)
+    key = get_ab_encrypt_key(key_str)
+    with open(os.path.join("bundles", file), 'rb') as f:
+        enc = f.read()
+    dec = xor_decrypt_data(enc, key)
+    with open(os.path.join("bundles-decrypt", file), "wb") as f:
+        f.write(dec)
 
 if __name__ == "__main__":
     if not os.path.isdir("bundles"):
-        print("copy bundle folders here")
+        print("请将需要解密的 'bundles' 文件夹放在此脚本旁边。")
+        exit()
+        
     if not os.path.isdir("bundles-decrypt"):
         os.mkdir("bundles-decrypt")
 
-    os.system("mkdir -p bundles-decrypt")
-    pool = multiprocessing.Pool()
-    pool.map(decrypt, os.listdir("bundles"))
-    pool.close()
-    pool.join()
\ No newline at end of file
+    with multiprocessing.Pool() as pool:
+        pool.map(decrypt, os.listdir("bundles"))
\ No newline at end of file