From 5b4291ee334d83675f1fc68cd63a71e245961881 Mon Sep 17 00:00:00 2001
From: xprism1 <xprism01@gmail.com>
Date: Thu, 24 Aug 2023 23:20:36 +0800
Subject: [PATCH] ctr_cnt: add support for cnt without CupList

---
 README.md      |  4 ++--
 lib/ctr_cnt.py | 63 +++++++++++++++++++++++++++++++++-----------------
 utils.py       |  2 +-
 3 files changed, 45 insertions(+), 24 deletions(-)

diff --git a/README.md b/README.md
index 8867bee..78517b9 100644
--- a/README.md
+++ b/README.md
@@ -31,8 +31,8 @@ python3 ntool.py cci_retail2dev <path_to_cci> (--out <path_to_output_file>)
 - **WARNING: Only perform this on SysNAND if you are able to use ntrboot to recover from a brick!**
 - First, obtain the SystemUpdaterForCTR zip file from NDP if you have a o3DS/o3DS XL/2DS. For n3DS/n3DS XL/n2DS XL, obtain the SystemUpdaterForSNAKE zip file instead
 - Extract the zip file, and choose the appropriate .csu file for your 3DS's region
-- Run `python3 ntool.py csu2retailcias <path_to_csu> updates/`
-- Place the `updates` folder in the root of your 3DS's SD
+- Run `python3 ntool.py csu2retailcias <path_to_csu>`
+- Place the `updates_retail` folder in the root of your 3DS's SD and rename it to `updates`
 - Install [sysUpdater](https://github.com/profi200/sysUpdater), launch it and follow the on-screen instructions
 - You may need to enable `Set developer UNITINFO` in Luma3DS settings
 
diff --git a/lib/ctr_cnt.py b/lib/ctr_cnt.py
index cbc5358..4a5b19e 100644
--- a/lib/ctr_cnt.py
+++ b/lib/ctr_cnt.py
@@ -1,5 +1,6 @@
 from .common import *
 from .keys import *
+from .ctr_cia import CIAReader
 
 class cntRecord(Structure):
     _pack_ = 1
@@ -31,29 +32,43 @@ class cntHdr(Structure):
         pass
 
 class cntReader:
-    def __init__(self, cuplist, cnt): # files named 'CupList' and 'Contents.cnt' respectively
-        self.cuplist = cuplist
+    def __init__(self, cnt, cuplist=''): # files named 'Contents.cnt' and 'CupList' respectively
         self.cnt = cnt
-
-        with open(cuplist, 'rb') as f:
-            cupdata = f.read()
-        
-        tidlist = []
-        for i in range(0, 0x800, 8):
-            if cupdata[i:i + 8] == b'\x00' * 8:
-                break
-            tidlist.append(hex(readle(cupdata[i:i + 8]))[2:].zfill(16))
-        self.tidlist = tidlist
-
-        with open(cnt, 'rb') as f:
-            self.cnt_hdr = cntHdr(f.read(0x1400))
-        
+        self.cuplist = cuplist
         files = {}
-        for i in range(len(tidlist)):
-            files[f'{tidlist[i]}.cia'] = {
-                'size': self.cnt_hdr.content_records[i].offset_end - self.cnt_hdr.content_records[i].offset,
-                'offset': self.cnt_hdr.content_records[i].offset + 0x1400 - 2048
-            }
+
+        if self.cuplist != '':
+            with open(cuplist, 'rb') as f:
+                cupdata = f.read()
+            
+            tidlist = []
+            for i in range(0, 0x800, 8):
+                if cupdata[i:i + 8] == b'\x00' * 8:
+                    break
+                tidlist.append(hex(readle(cupdata[i:i + 8]))[2:].zfill(16))
+            self.tidlist = tidlist
+
+            with open(cnt, 'rb') as f:
+                self.cnt_hdr = cntHdr(f.read(0x1400))
+            
+            for i in range(len(tidlist)):
+                files[f'{tidlist[i]}.cia'] = {
+                    'size': self.cnt_hdr.content_records[i].offset_end - self.cnt_hdr.content_records[i].offset,
+                    'offset': self.cnt_hdr.content_records[i].offset + 0xC00 # Offsets are relative from the start of the content records
+                }
+        else:
+            with open(cnt, 'rb') as f:
+                f.seek(0xC00)
+                content_records = f.read(0x800)
+                for i in range(0, 0x800, 8):
+                    offset = readle(content_records[i:i + 4])
+                    offset_end = readle(content_records[i + 4:i + 8])
+                    if offset == 0:
+                        break
+                    files[f'{(i // 8) + 1}.cia'] = {
+                        'size': offset_end - offset,
+                        'offset': offset + 0xC00
+                    }
         self.files = files
 
     def extract(self):
@@ -68,6 +83,12 @@ class cntReader:
             for data in read_chunks(f, info['size']):
                 g.write(data)
             g.close()
+
+            # Rename CIAs if no cuplist
+            if self.cuplist == '':
+                cia = CIAReader(os.path.join(output_dir, name))
+                titleID = cia.tmd.titleID
+                os.rename(os.path.join(output_dir, name), f"{os.path.join(output_dir, titleID)}.cia")
         
         f.close()
         print(f'Extracted to {output_dir}')
\ No newline at end of file
diff --git a/utils.py b/utils.py
index 74aa783..df407b5 100644
--- a/utils.py
+++ b/utils.py
@@ -669,7 +669,7 @@ def csu2retailcias(path, out=''):
     romfs = RomFSReader('romfs.bin')
     romfs.extract()
 
-    cnt = cntReader('romfs/contents/CupList', 'romfs/contents/Contents.cnt')
+    cnt = cntReader('romfs/contents/Contents.cnt', 'romfs/contents/CupList')
     cnt.extract()
 
     for i in ['cci_header.bin', 'card_info.bin', 'mastering_info.bin', 'initialdata.bin', 'card_device_info.bin', 'content0.game.ncch', 'ncch_header.bin', 'exheader.bin', 'logo.bin', 'plain.bin', 'exefs.bin', 'romfs.bin']: