Title Database

These files contain data relating to install/usage/management of installed 3DS titles. The database files are located at:

• nand/dbs
• sdmc/Nintendo 3DS/<ID0>/<ID1>/dbs

ID0 is the first 0x10-bytes from a SHA256 hash. The installation of SD Card titles was introduced in the 2.0.0-2 update and the SD dbs files are encrypted. These files are extdata images. The NAND extdata images are cleartext, however some of the images contain data encrypted with a console-unique keyslot.

These files are stored under this directory:

Stored on SD card	Stored in CTR-NAND	Filename	CTR-9DB0 ID	Description
Yes	Yes	import.db	0x3	This is an Import Database, it contains entries for titles(or versions of titles) not yet installed, ready for transferring to the title.db. (Automatic Update uses this, so completing the update takes seconds)
Yes	Yes	title.db	0x2	Title database, this contains entries for all installed titles (TWL & CTR) on the 3DS(Each database is responsible for titles installed on it's medium).
No	Yes	tmp_t.db	?	This is the temporary Title database containing one entry for the currently installed Download Play Child.
No	Yes	tmp_i.db	?	Similar to import.db, except it's used in conjunction with tmp_t.db, for installing Download Play Children.
No	Yes	certs.db	?	This contains the certificate chain used to verify TMDs and other certificates.
No	Yes	ticket.db	?	This contains the installed tickets.

The .db Extdata image embeds two almost identical copies(the latter is probably an older backup) of the title database. These database files consist of a pre-header with size of 0x80 identifying the Database Type, followed by a BDRI container. The offsets in the BDRI header are usually relative to the offset to the start of the BDRI header (0x80 in the file)

Pre Header

Start	Length	Description
0x00	8	Database Type "Magic" (see below)
0x08	0x78	Reserved

Database Magic

Database Type	Magic
CTR-NAND import.db	NANDIDB
CTR-NAND title.db	NANDTDB
CTR-NAND tmp_i.db	TEMPIDB
CTR-NAND tmp_t.db	TEMPIDB
SD Card import.db	?
SD Card title.db	TEMPTDB

BDRI

Information stored about titles in these Title Database files are stored in two parts in a BDRI partition. Firstly in a Title Entry Table, and secondly in a Title Info Table.

Start	Length	Description
0x0	4	Database Magic ("BDRI")
0x4	4	Magic Number (0x30000)
0x8	8	Unknown
0x10	8	File Size(including pre header), divided by the value at relative offset 0x18 (usually = 0x80)
0x18	4	Usually 0x80
0x1C	4	Reserved
0x20	0x20	Unknown/Constant
0x40	0x18	Unknown
0x58	8	Relative Title Entry Table Offset
0x60	0x20	Unknown

Title Entry Table

This contains 'Entries' for all the titles stored in the database. However this just appears to be an indexing table, the majority of title information is kept in a Title Info Table, which these index entries point to. Title Entries start immediately after the Title Entry Table Header. And there is no padding between entries.

Header

Start	Length	Description
0x0	4	Unknown/Magic? (usually = 0x2)
0x4	4	Unknown/Magic? (usually = 0x3)
0x8	0x24	Reserved
0x2C	4	Number of used Title Entries
0x30	0x50	Reserved
0x80	4	MAX Number of Title Entries
0x84	4	Unknown
0x88	0x20	Reserved

Title Entry Format

The entries are 0x2C bytes long.

Start	Length	Description
0x0	4	Unknown
0x4	4	Entry Flag. If this isn't = 0x1, then this entry slot is unused
0x8	0x8	Title ID
0x10	4	Title Entry Index
0x14	4	Relative Title Info Offset, divided by the value at offset 0x18 in this Title Entry (usually 0x80)
0x18	0x4	Usually 0x80
0x1c	4	Reserved
0x20	4	Unknown, occasionally this value is the title's "Title ID lower"
0x24	0x4	Unknown
0x28	0x4	Unknown

• The actual Title Info offset is calculated by the following: Offset of BDRI Header + Relative Offset of Title Entry Table + Relative Title Info Offset

Title Info Table

These consist of 0x80 byte long entries, pointed to by the title index entries. They contain information taken from both the application NCCH file(s) and TMD.

Start	Length	Description
0x0	8	Title Size
0x8	4	Title Type(usually 0x40)
0xC	4	Title Version
0x10	4	Flags_0
0x14	4	TMD Content ID
0x18	4	CMD Content ID
0x1c	4	Flags_1
0x20	4	ExtdataID low (zero if title doesn't use Extdata)
0x24	4	Reserved
0x28	8	Flags_2
0x30	0x10	Product Code
0x40	0x10	Reserved
0x50	0x4	Unknown
0x54	0x2c	Reserved

Flags_0

Index	Description
0	Electronic Manual
1	?
2	?
3	?

Flags_1

Index	Description
0	SD Save Data
1	?
2	?
3	?

Flags_2

Index	Description
0	DSiWare Related (Visibility on Home Menu/Export Flag?)
1	?
2	?
3	?
4	Found with DSiWare Titles and titles with an 'Application' Title ID
5	DSiWare Related (Visibility on Home Menu/Export Flag?)
6	?
7	?

NOTES:

It is important to note the database doesn't contain a hash of the .cmd. So if a user has more than one valid set of application data for a given .cmd Content ID they can be manually interchanged without issue. Though renaming a .cmd file to match the Content ID which the title.db is expecting will result in an error, as the CTR for the per-console encryption layer changes depending on the file path, and the MAC of the .cmd is probably generated with the .cmd Content ID in mind.

These NAND/SD /dbs images seem to be loaded by the ARM9 while NATIVE_FIRM is booting.

Tools

extdata_tool - parsing cleartext .db extdata images