From b3923cfe405d78b0262f537525de8ae011eaaf02 Mon Sep 17 00:00:00 2001
From: NinjaCheetah <58050615+NinjaCheetah@users.noreply.github.com>
Date: Sun, 3 Mar 2024 22:05:30 -0500
Subject: [PATCH] This makes 00000001.app work

---
 src/libWiiPy/content.py |  6 +++---
 src/libWiiPy/crypto.py  | 11 ++++++-----
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/src/libWiiPy/content.py b/src/libWiiPy/content.py
index 2d47b0c..5eebe2b 100644
--- a/src/libWiiPy/content.py
+++ b/src/libWiiPy/content.py
@@ -35,7 +35,7 @@ class ContentRegion:
             self.num_contents = len(self.content_records)
             # Calculate the offsets of each content in the content region.
             for content in self.content_records[:-1]:
-                start_offset = int(16 * round(content.content_size / 16)) + self.content_start_offsets[-1]
+                start_offset = int(64 * round(content.content_size / 64)) + self.content_start_offsets[-1]
                 self.content_start_offsets.append(start_offset)
 
     def get_enc_content(self, index: int) -> bytes:
@@ -55,7 +55,7 @@ class ContentRegion:
             # Seek to the start of the requested content based on the list of offsets.
             content_region_data.seek(self.content_start_offsets[index])
             # Calculate the number of bytes we need to read by rounding the size to the nearest 16 bytes.
-            bytes_to_read = int(16 * round(self.content_records[index].content_size / 16))
+            bytes_to_read = int(64 * round(self.content_records[index].content_size / 64))
             # Read the file based on the size of the content in the associated record.
             content_enc = content_region_data.read(bytes_to_read)
             return content_enc
@@ -77,7 +77,7 @@ class ContentRegion:
         """
         # Load the encrypted content at the specified index and then decrypt it with the Title Key.
         content_enc = self.get_enc_content(index)
-        content_dec = decrypt_content(content_enc, title_key, self.content_records[index].index)
+        content_dec = decrypt_content(content_enc, title_key, self.content_records[index].index, self.content_records[index].content_size)
         # Hash the decrypted content and ensure that the hash matches the one in its Content Record.
         # If it does not, then something has gone wrong in the decryption, and an error will be thrown.
         content_dec_hash = hashlib.sha1(content_dec)
diff --git a/src/libWiiPy/crypto.py b/src/libWiiPy/crypto.py
index 7c4c0ee..4e8abef 100644
--- a/src/libWiiPy/crypto.py
+++ b/src/libWiiPy/crypto.py
@@ -39,7 +39,7 @@ def decrypt_title_key(title_key_enc, common_key_index, title_id):
     return title_key
 
 
-def decrypt_content(content_enc, title_key, content_index):
+def decrypt_content(content_enc, title_key, content_index, content_length):
     """Gets the decrypted version of the encrypted content.
 
     Requires the index of the common key to use, and the Title ID of the title that the Title Key is for.
@@ -62,15 +62,16 @@ def decrypt_content(content_enc, title_key, content_index):
         content_index_bin += b'\x00'
     # In CBC mode, content must be padded out to a 16-byte boundary, so do that here, and then remove bytes added after.
     padded = False
-    if (len(content_enc) % 64) != 0:
+    if (len(content_enc) % 128) != 0:
         print("needs padding to 16 bytes")
-        content_enc = pad(content_enc, 64, "pkcs7")
+        content_enc = pad(content_enc, 128, "pkcs7")
         padded = True
     # Create a new AES object with the values provided, with the content's unique ID as the IV.
     aes = AES.new(title_key, AES.MODE_CBC, content_index_bin)
     # Decrypt the content using the AES object.
     content_dec = aes.decrypt(content_enc)
     # Remove padding bytes, if any were added.
-    #if padded:
-        #content_dec = unpad(content_dec, AES.block_size)
+    if padded:
+        while len(content_dec) > content_length:
+            content_dec = content_dec[:-1]
     return content_dec