Nintendo GameCube DVD Format

[Cyndanera]

You can find my write up here: https://www.gc-forever.com/wiki/index.p ... =DVDFormat
If I'm missing anything or it needs corrections feel free to reply below.
Please Note this reverse engineering the format is WIP.

GameCube Disc Format aka NROM(Read-only) or NR-Disc(Rewritable)
XOR Encryption is done using discId and a randomKey by the Disc Controller Firmware, Panasonic MN103S and is controlled by the System Controller MN102H that does BCA

Copy Protection

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Custom Data Sector Format(Data Frames)
Custom Filesystem
Sectors are encrypted by DiskID(Key1) and RandomKey(Key2)
DiskID = GameID + MakerID

RandomKeys:
  0: 3
  1: 48
  2: 32512
  3: 28673
  4: 6
  5: 69
  6: 32256
  7: 24579
  8: 12
  9: 192
  10: 31744
  11: 16391
  12: 24
  13: 384
  14: 30720
  15: 15

Check for the Security Code of 6 BCA marks on the disc, from the 6 positions stored on the BCA encrypted area
The 6 BCA mark positions corrupt the sector data stored on the disc, the BCA data tells the locations.
Disc sectors get decrypted with a DiscID and RandomKey from RandomKey list. using the MN102H & MN103S system controller in the DVD drive
Encryption doesn't have a random key for NR disc instead it's a fixed key after the discID, the fixed key value is 9
Encryption with the gamecode and random key xor encryption is similar to the nintendo ds

Encryption(XOR): DiscID(KEY1) -> RandomKey(KEY2)
Security Check: Get DiscID -> Check BCA Marks -> Run Apploader code -> BOOT

Physical Format

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// Burst-Cutting Area(BCA)
struct_DiscBca
{
    // UserData(unencrypted), 64B
    u8 optInfo[52]; // optional info this can be any data access with the new command on the wii, this is used in NSMB Wii
    u8 manufacturer[2];
    u8 recorderDevice[2];
    u8 bcaSerial;
    u8 discDate[2];
    u8 discTime[2];
    u8 discNumber[3];
    // SecureData(unencrypted), 12B
    u8 key[8];
    u8 id[4];
    // AuthenticationData(encrypted with key), 48B
    PsnRegion psn[6];
    u8 pad[64];
}; // 188B

struct_PsnRegion
{
    u32 start;
    u32 end;
};

struct_DataFrame
{
    u32 id; // PSN(Physical Sector Number)
    u16 ied; // ID Error Detection Code, CRC16
    u8 userdata[2048]; // Data
    u8 cpr_mai[6]; // Copyright Management Information(Unused)
    u32 edc; // Error Detection Code, CRC32
}; // 2064B

struct_ControlDataZone
{
    DiscManufacturingInfo m_dmi;
    PhysicalFormatInfo m_pfi;
};

struct_PhysicalFormatInfo
{
    u8 reversed[6];
    u8 discMagic; // value is -1.
    u8 discSizeMinTransferRate; // The value is fixed on 16.
    u8 discStructure; // The value is fixed on 1.
    u8 recordedDensity; // The value is fixed on 1.
    DataAreaAllocation m_dataAreaAllocation;
    u8 reversed2[2000];
    u8 reversed3[6];
}; // 2048B

struct_DiscManufacturingInfo
{
    u8 reversed[6];
    u8 secret1[6];
    u8 randomNumber2[6];
    u8 secret2[6];
    u8 randomNumber3[6];
    char mediaId[19]; // "Nintendo Game Disk"
    u8 randomNumber4[6];
    u8 bookTypePartVersion; // value must be 1.
    u8 discSizeMinReadoutRate; // The value is fixed on 16.
    u8 discStructure; // The value is fixed on 1.
    u8 recordedDensity; // The value is fixed on 0.
    DataAreaAllocation m_dataAreaAllocation;
    u8 bcaDescriptor; // The value is fixed on 128.
    u8 reversed2[1967];
    u8 reversed3[6];
}; // 2048B

struct_DataAreaAllocation
{
    u8 reversed;
    u16 startSector; // 196608
    u8 reversed2;
    u16 endSector; // 909487
    u8 reversed3[3];
}; // 12 Bytes

Disc Image Format

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struct_root
{
    BootHeader m_header; // boot.bin
    BootHeaderInfo m_bi; // bi2.bin
    AppLoader m_apploader; // appldr.img
    FileSystemTable m_fst; // fst.bin
    u8* userdata; // application is stored here, including boot file
};

struct_BootHeader
{
    u8 ConsoleID; // G = Gamecube, R = Wii.
    u8 Gamecode[2];
    u8 CountryCode;    // J=JAP . P=PAL . E=USA
    u8 MakerCode[2];
    u8 DiscID;
    u8 Version;
    u8 AudioStreaming; //01 = Enable it. 00 = Don't
    u8 StreamBufSize; // For the AudioEnable.
    u8 unused_1[18];    
    u32 DVDMagicWord; // 3258163005
    char GameName[64];
    u8 unused_2[416];
    u32 NKitMagicWord;
    u32 NKitVersion;
    u32 ImageCRC;
    u32 ForceCRC;
    u32 ImageSize;
    u32 JunkID;
    u8 unused_3[488];
    u32 ApploaderSize;
    u32 ApploaderFunc1;
    u32 ApploaderFunc2;
    u32 ApploaderFunc3;
    u8 unused_4[16];
    u32 DOLOffset;
    u32 FSTOffset;
    u32 FSTSize;
    u32 MaxFSTSize;
    u32 FSTAddress;
    u32 UserPos;
    u32 UserLength;
    u32 unused_5;
};

struct_BootHeaderInfo
{
    u32 DebugMonSize;
    u32 SimMemSize;
    u32 ArgOffset;
    u32 DebugFlag;
    u32 DebugOffset;
    u32 DebugSize;
    u32 RegionCode;
    u32 TotalDisc;
    u32 LongFileName;
    u32 padSpec;
    u32 dolLimit;
    u8 pad[8148];
}; // 8192 Bytes

struct_AppLoader
{
    char revision[16]; // Revision compile date (example "2001/12/17")
    u32 entryPoint; // Apploader's entrypoint
    u32 size; // Size of apploader code
    u32 rebootSize; // Size of reboot code
    u8 pad[4]; // zeroes
    u8* code; // PPC code
};

struct_FileSystemTable
{
    u32 entityCount;
    FileSystemEntity* m_entity;
    StringTable* m_string;
};

struct_FileSystemEntity
{
    u8 flags;
    u16 filenameOffset;
    u32 fileOffset;
    u32 fileSize;
};

struct_StringTable
{
    char* name;
    u8 dummy;
};