Difference between revisions of "NCSD"

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(There is no such thing as NCSD exheader)
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The region-specific NVer title for this NCSD presumably must exist on NAND. The NVer title version may also be used to check whether a system update is required before running the app.
 
The region-specific NVer title for this NCSD presumably must exist on NAND. The NVer title version may also be used to check whether a system update is required before running the app.
 
== NCSD ExHeader ==
 
{| class="wikitable" border="1"
 
|-
 
!  OFFSET
 
!  SIZE
 
!  DESCRIPTION
 
|-
 
|  0x1000
 
|  8
 
|  Title ID of main NCCH
 
|-
 
|  0x1008
 
|  8
 
|  Reserved
 
|-
 
|  0x1010
 
|  0x30
 
|  Initial Data
 
|-
 
|  0x1040
 
|  0xC0
 
|  Reserved
 
|-
 
|  0x1100
 
|  4
 
|  Magic ID, always 'NCCH'
 
|-
 
|  0x1104
 
|  4
 
|  Content size, in media units (1 media unit = 0x200 bytes)
 
|-
 
|  0x1108
 
|  8
 
|  Partition ID
 
|-
 
|  0x1110
 
|  2
 
|  Maker code
 
|-
 
|  0x1112
 
|  2
 
|  Version
 
|-
 
|  0x1114
 
|  4
 
|  Reserved
 
|-
 
|  0x1118
 
|  8
 
|  Program ID
 
|-
 
|  0x1120
 
|  1
 
|  Temp flag
 
|-
 
|  0x1121
 
|  0x2F
 
|  Reserved
 
|-
 
|  0x1150
 
|  0x10
 
|  Product code
 
|-
 
|  0x1160
 
|  0x20
 
|  Extended header hash (SHA-256), over the cleartext ExHeader
 
|-
 
|  0x1180
 
|  4
 
|  Extended header size
 
|-
 
|  0x1184
 
|  4
 
|  Reserved
 
|-
 
|  0x1188
 
|  8
 
|  Flags: byte[5]-byte[7] indicate content type ( system update, application, manual, ... ) size of media unit ( 512*2^byte[6] ) and encryption.
 
|-
 
|  0x1190
 
|  4
 
|  Plain region offset, in media units
 
|-
 
|  0x1194
 
|  4
 
|  Plain region size, in media units
 
|-
 
|  0x1198
 
|  8
 
|  Reserved
 
|-
 
|  0x11A0
 
|  4
 
|  ExeFS offset, in media units
 
|-
 
|  0x11A4
 
|  4
 
|  ExeFS size, in media units
 
|-
 
|  0x11A8
 
|  4
 
|  ExeFS hash region size, in media units
 
|-
 
|  0x11AC
 
|  4
 
|  Reserved
 
|-
 
|  0x11B0
 
|  4
 
|  RomFS offset, in media units
 
|-
 
|  0x11B4
 
|  4
 
|  RomFS size, in media units
 
|-
 
|  0x11B8
 
|  4
 
|  RomFS hash region size, in media units
 
|-
 
|  0x11BC
 
|  4
 
|  Reserved
 
|-
 
|  0x11C0
 
|  0x20
 
|  ExeFS superblock hash, over the cleartext ExeFS
 
|-
 
|  0x11E0
 
|  0x20
 
|  RomFS superblock hash
 
|-
 
|  0x1200
 
|  0x2E00
 
|  Reserved/Unused (Is filled with either 'F's or '0's)
 
|}
 
From the magic 'NCCH' to the end of the 'RomFS superblock hash' the data is identical to the [[NCCH#NCCH Header|NCCH Header]] of the [[NCCH#CXI|Executable NCCH]] Partition (NCCH 0).
 

Revision as of 15:50, 28 July 2012

This page documents the format of NCSD.

Overview

There are two known specialisations of the NCSD container format. The CTR Cart Image (CCI) format and the CTR System Update (CSU). CCI is the format of retail game ROM dumps. CSU is used with developer system updates and tools

NCSD images start with a NCSD header, followed by up to a maximum of 8 NCCH partitions. The first partition(NCCH 0) usually starts at 0x4000, this is generally the main NCCH (Executable). The following info on partitions 1, 2, and 7 are only valid for .CCI. The second partition(NCCH 1) contains the game "Manual"(title ID for the .CFA containing the Manual always starts with '0005'). The third partition(NCCH 2) contains the download play "Child"(The title ID for the .CFA containing the DLP Child always starts with '0006'). The eighth block(NCCH 7) contains "Update Data"(The title ID for the .CFA containing the Update Data always starts with '8000') The format of partitions can be determined from the partition FS flags, while the contents can be determined from the partitions flags.

NCSD header

Offset Size Description
0x000 0x100 RSA-2048 SHA-256 signature of the NCSD header
0x100 4 Magic Number 'NCSD'
0x104 4 Size of the NCSD image, in media units (1 media unit = 0x200 bytes)
0x108 8 Title/Program ID
0x110 8 Partitions FS type
0x118 8 Partitions crypt type
0x120 0x40=(4+4)*8 Offset & Length partition table
0x160 0x20 Exheader SHA-256 hash
0x180 0x4 Additional header size
0x184 0x4 Sector zero offset
0x188 8 Partition Flags: byte[5]-byte[7] indicate content type ( system update, application, manual, ... ) size of media units ( 512*2^byte[6] ) and encryption.
0x190 0x40=8*8 Partitions' Title ID table
0x1D0 0x28 Reserved
0x1F8 8 Unknown
0x200 4 Always 0xFFFFFFFF
0x204 252 Padding?
0x300 4 Used ROM size in bytes
0x304 28 Padding
0x320 8 NVer Title ID (Only Present in retail .CCI)
0x328 8 NVer Title Version (Only Present in retail .CCI)

Parts of the first NCCH block's header are found around 0x1000 for whatever reason. NCSD can hold up to 8 partitions. (i.e. Mario Kart 7 holds 4 NCCHs, most we've seen so far)

The region-specific NVer title for this NCSD presumably must exist on NAND. The NVer title version may also be used to check whether a system update is required before running the app.