CIA

Overview

CIA stands for CTR Importable Archive. These files contain a compiled application which can be installed on CTR NAND, TWL NAND (part of the NAND used by DSi applications) and on the SD card. CIA files can be created with the Nintendo 3DS SDK and installed on the 3DS test units by the Dev Menu.

Format

The CIA format based on WAD format, so the structure is very similar to the WAD structure.

The file is represented in little-endian.

The data is aligned in 64 byte blocks (if a content ends at the middle of the block, the next content will begin from a new block).

CIA Header

This is a 32 bytes long header (8 x uint32).

START	SIZE	DESCRIPTION
0x00	0x04	Archive Header Size (=0x2020 bytes) (Starts with 0x80 @ offset 0x0020)
0x04	0x04	Reserved = 0
0x08	0x04	Certificate chain size
0x0C	0x04	Ticket size
0x10	0x04	TMD file size
0x14	0x04	Banner size (0 if no banner)
0x18	0x04	APP file size
0x1C	0x04	0x80000000

The order of the sections in the header also is the order of them in the CIA file:

• certificate chain
• Ticket
• TMD file data
• APP file data
• banner

The data of the files is decrypted.

Banner

The banner starts with a 0xF0 large data block, whose purpose is currently unknown. Then at offset 0x400 into the banner section is the actual banner, which contains information about the creator, the first title and the second title (you can see them in the system settings):

START	SIZE	DESCRIPTION
0x00	0x04	Magic: 'SMDH'
0x05	0x04	Reserved = 0

This small 'header' is immediately followed by a 0x80 large block for the application name (first title) and then a 0x100 bytes large block for the second title (this title will be shown in the system settings). After that there's alway the same order:

• publisher name (aligned to 0x80 bytes)
• first title (aligned to 0x80 bytes)
• second title (aligned to 0x100 bytes)

This order will repeat 10 times, thus there's a 0x1660 bytes large space for these information.