Flash Filesystem

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Revision as of 00:11, 19 July 2017 by Missile (talk | contribs) (clarify the intention of cmac check function, this is actually identical to a fix deployed on xbox360 cb)
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NAND structure

Boot Partitions

Boot Partition 0 (0 of 1)

Offset Size Description
0x000000 0x4000 Title 0100000000000819 BCT
0x004000 0x4000 Title 010000000000081A BCT
0x008000 0x4000 Title 0100000000000819 BCT
0x00C000 0x4000 Title 010000000000081A BCT
0x100000 0x40000 Title 0100000000000819 "package1"
0x140000 0x40000 Title 0100000000000819 "package1" (Backup)
0x180000 0x4000 Keyblob area
0x184000 Unknown, 0x20-bytes hash (updated when bcpkg-2-1 updates) + one u64? (may be incremented on bcpkg update) All zero on 1.0.

Boot Partition 1 (1 of 1)

Offset Size Description
0x000000 0x40000 Title 010000000000081A "package1"
0x040000 0x40000 Title 010000000000081A "package1" (Backup)
0x080000 0x40000
0x0C0000 0x40000

Keyblob

Offset Size Description
0x0 0x10 Keyblob AES-CMAC over the remaining 0xA0-bytes (Checked with a mem-diff function which is safe against timing attacks, calls the general panic() func on failure)
0x10 0x10 Keyblob AES CTR
0x20 0x90 Keyblob encrypted payload
0xB0 0x150 Unused, all-zero.

Starting at 0x180000 is an array of 0x200-byte entries, for a total of 32 keyblobs. Each one is unique compared to the others. They are all console unique.

The 0xB0-byte keyblob is installed to the "customer data" section in BCTs (BCT+0x450).

BCT offset 0x2330 is the field controlling which keyblob gets used. NS uses this to inject the appropriate keyblob on system update. Boot also uses this index for repairing corrupt sectors.

With [ 3.0.0 + ] index 2 is used instead of index 1.

The Tegra 210 BCT format can be found in nvidia's cbootimage [1]

User Partitions

Partition name Offset Size Bis Partition ID Description
N/A 0x0 20 GPT header, Bis-storage also allows raw access to the entire NAND eMMC sectors starting at sector0.
PRODINFO 0x00004400 0x003FBC00 27 "CAL0" raw partition containing set:cal data.
PRODINFOF 0x00400000 0x00400000 28 FAT12 filesystem, additional calibration.
BCPKG2-1-Normal-Main 0x00800000 0x00800000 21 For all these packages, data starts at offset 0x4000 and is not console-unique. This is installed from "package2" in firmware package A (0100000000000819) by default. With the exFAT update installed, this is switched to firmware package C (010000000000081B). The data stored here matches the raw /nx/package2 file stored in the 81[9AB] data archives -- there is no additional encryption.
BCPKG2-2-Normal-Sub 0x01000000 0x00800000 22 Identical to BCPKG2-1-Normal-Main, probably used as a backup partition.
BCPKG2-3-SafeMode-Main 0x01800000 0x00800000 23 This is installed from "package2" in firmware package B (010000000000081A).
BCPKG2-4-SafeMode-Sub 0x02000000 0x00800000 24 Identical to BCPKG2-3-SafeMode-Main.
BCPKG2-5-Repair-Main 0x02800000 0x00800000 25 Installed at the factory.
BCPKG2-6-Repair-Sub 0x03000000 0x00800000 26 Identical to BCPKG2-5-Repair-Main.
SAFE 0x03800000 0x04000000 29 FAT32 filesystem.
SYSTEM 0x07800000 0xA0000000 31 (and 32?) FAT32 filesystem.
USER 0xA7800000 0x680000000 30 FAT32 filesystem.
0x747BFFE00 0x200 This is the backup GPT header specified by the main GPT header. This is also the last sector readable with Bis-storage paritionID 20.

If the client process lacks the relevant permission for any of the above partition IDs, error 0x2EE202 is returned.

NCAs stored in NAND are raw, identical to the data readable with Content_Manager_services#ReadEntryRaw.

The filenames for saveimages is just "<lower-case hex u64 saveID>". SYSTEM-partition saveIDs are specified by FS commands, while USER-partition saveIDs are determined by FS-module internally. The high u32 of the saveID is normally either 0x00000000 or 0x80000000.

PRODINFOF

PRODINFOF
├── Certifications
│   └── WirelessCertification.png
└── ptd
    ├── DeviceIdWithEmsBit.dat
    ├── Ecid.dat
    ├── prodCode.dat
    └── log
        ├── Process_asm1.log
        ├── Process_board1.log
        ├── TestFlagLine.log
        ├── TestFlagQc.log
        ├── AGING
        │   └── Sequence.log
        ├── BOARD_TEST
        │   └── Sequence.log
        ├── BOARD_WIRELESS
        │   └── Sequence.log
        ├── FINAL_CHECK
        │   └── Sequence.log
        ├── LCD_AND_KEY
        │   └── Sequence.log
        └── USB_AND_HP
            └── Sequence.log

DeviceIdWithEmsBit.dat

Contains a 0x10-byte uppercase hex string, identical to the DeviceId in the DeviceCert.

SYSTEM

SYSTEM
├── PRF2SAFE.RCV
├── Contents
│   ├── registered
│   │   └── ... NCA
│   └── placehld
│       └── ... NCA
├── save
│   └── ...
└── saveMeta
    └── ... (empty?)

The saves stored under this partition are only for system-titles / etc.

USER

USER
├── PRF2SAFE.RCV
├── Album (Same layout as SD)
├── Contents
│   ├── registered
│   │   └── ... NCA
│   └── placehld
│       └── ... NCA
├── save
│   └── ...
├── saveMeta
│   └── ... 
└── temp 

The saves for all non-system applications, regardless of where the application is located(storageID), is stored here. Each user account which has savedata has a separate saveimage. Save-common for an application is presumably a separate saveimage too. Every saveimage here is only for applications.

SAFE

SAFE
├── PRF2SAFE.RCV
├── Contents
│   ├── registered
│   │   └── ... NCA (nothing installed?)
│   └── placehld
│       └── ... NCA
└── save
    ├── 8000000000000000
    └── 8000000000000120

On a v2.1 system with MountBis, the only thing under here is "PRF2SAFE.RCV".

System Savegames

This is a listing of known System Savedata and what titles they correspond to.

SaveID Owner Notes
0x80000000000000d1 erpt Contains "/journal" report listing + actual crash reports ("/%08x-%04x-%04x-%02x%02x-%04x%08x"), which are serialized via MsgPack.