Bluray disc

Overview

• UDF filesystem (a profile of ECMA-167) in cleartext
• File entries are not encrypted, some files are not encrypted
• Some regions of the disc are encrypted (sector by sector)
• One sector is 2048 bytes

Encryption

The first sector of the disc tells which parts of the disc are unencrypted and which one are encoded.

For example, this is the beginning of "The Last of Us" disc:

00000000: 0000 0003 0000 0000 0000 0000 0000 099f  ................
00000010: 00a2 6160 00ba 73ff 011d dda0 011f ddbf  ..a`..s.........
00000020: 0000 0000 0000 0000 0000 0000 0000 0000  ................

• 0x00000003 is the number of unencrypted regions
• The first unencrypted region is from sector 0x00000000 to sector 0x0000099f
• The first encrypted region is from sector 0x0000099f to sector 0x00a26160
• The second unencrypted region is from sector 0x00a26160 to sector 0x00ba73ff
• The second encrypted region is from sector 0x00ba73ff to sector 0x011ddda0
• The third unencrypted region is from sector 0x011ddda0 to sector 0x011fddbf
• 0x011fddbf sectors is 38636746752 bytes whereas the file is 38636748800 bytes : the last sector is not included for some reason.

Deriving the disc key

The disc key is obtained by encrypting "data1" with AES CBC:

• with the secret 0x380bcf0b53455b3c7817ab4fa3ba90ed
• with the IV 0x69474772af6fdab342743aefaa186287
• no padding
• data1 is available in the IRD file
• it can be found on the disc with a bunch of SCSI commands.

Sector encryption

Each sector is encrypted with AES CBC:

• using the disc key
• no padding

The IV is derived from the sector number with:

int num = sectorNumber;
byte[] iv = new byte[16];
for (int j = 0; j < 16; j++)
{
	iv[16 - j - 1] = (byte)(num & 0xFF);
	num >>= 8;
}

File system layout

• PS3_DISC.SFB
• PS3_GAME/ICON0.PNG
• PS3_GAME/LICDIR/LIC.DAT
• PS3_GAME/PARAM.SFO
• PS3_GAME/PIC1.PNG
• PS3_GAME/PS3LOGO.DAT
• PS3_GAME/SND0.AT3
• PS3_GAME/TROPDIR/
• PS3_GAME/USRDIR/build/
• PS3_GAME/USRDIR/data/
• PS3_GAME/USRDIR/EBOOT.BIN
• PS3_UPDATE/PS3UPDAT.PUP

PS3 Disc Game Structure

Disc Path					XMB icon	SFB/SFO/SFX Mandatory Parameters						Since	Enabled by
						APP_VER	ATTRIBUTE	BOOTABLE	CATEGORY	TITLE	TITLE_ID
dev_bdvd/	PS3_DISC.SFB										Yes	1.00	Enables others with HYBRID_FLAG
	PS3_GAME/	PARAM.SFO				Opt	Opt	Opt	DG	Yes	Yes	1.00	HYBRID_FLAG (g) in PS3_DISC.FSB
		USRDIR/	EBOOT.BIN									1.00	BOOTABLE (1) in parent PARAM.SFO
		INSDIR/	PARAM.SFO		No?	Yes	No	No	AR	No	No	?	HYBRID_FLAG (g) in PS3_DISC.FSB ?
			DATA000.PKG (up to 999)									?
		PKGDIR/	PARAM.SFO			No	Yes	No	DP	Yes	Yes	1.00 ?	ATTRIBUTE (131072) in parent PARAM.SFO
			PKG01/ (up to 99)	PARAM.SFO		No	No	No	IP	Yes	Yes	1.00 ?	ATTRIBUTE (1) in parent PARAM.SFO
				INSTALL.PKG								1.00 ?
		LICDIR/	LIC.DAT									1.00
		TROPDIR/	<NPCOMMID>/	TROPHY.TRP								2.40
	PS3_GM01/ (up to 99?)	PARAM.SFO				Opt	Opt	Opt	DG	Yes	Yes	4.00+ ?	HYBRID_FLAG (g) in PS3_DISC.FSB
		USRDIR/	EBOOT.BIN									4.00+ ?	BOOTABLE (1) in parent PARAM.SFO
		LICDIR/	LIC.DAT									4.00+ ?	dev_bdvd/PS3_GAME/LICDIR/LIC.DAT
	PS3_CONTENT/	THEMEDIR/	PARAM.SFO			No	Yes	No	TR	Yes	No ?	2.00+	HYBRID_FLAG (T) in PS3_DISC.FSB
			D001/	DATA001.P3T (up to 999)								2.00+	ATTRIBUTE (1) in parent PARAM.SFO
		VIDEODIR/	PARAM.SFO			No	Yes	No	VR	Yes	No ?	?	HYBRID_FLAG (V) in PS3_DISC.FSB
			D001/ (up to 999)	PARAM.SFO	?	No	No	No	VI	Yes	No	?	ATTRIBUTE (1) in parent PARAM.SFO
				DATA000.MP4								?
	PS3_EXTRA/	PARAM.SFO				No	Yes	No	XR	Yes	Yes	3.41-	HYBRID_FLAG (g) in PS3_DISC.FSB ?
		D001/ (up to 999)	PARAM.SFX			No	No	No	IP	Yes	No	3.41-	ATTRIBUTE (1) in parent PARAM.SFO
			DATA000.PKG									3.41-
		D002/ (up to 999)	PARAM.SFX			No	No	No	TI	Yes	No	3.41-	ATTRIBUTE (1) in parent PARAM.SFO
			DATA000.P3T									3.41-
		D003/ (up to 999)	PARAM.SFX			No	No	No	VI	Yes	No	3.41-	ATTRIBUTE (1) in parent PARAM.SFO
			DATA000.MP4									3.41-
	PS3_VPRM/	PARAM.SFO				No	No	No	DM	No	No	?	HYBRID_FLAG (v) in PS3_DISC.FSB
	PS3_UPDATE/	PS3UPDAT.PUP										1.00 ?	HYBRID_FLAG (u) in PS3_DISC.FSB

See also Content Information Files

Extra "tracks"

Disc Information from PIC in pre-recorded area

This information is in the PIC zone. It can be read with the READ DISC STRUCTURE SCSI command with arguments for BluRay.

For example (on Linux),

  unsigned char read_pic_command[12] = {
    173, // Operation Code=READ_DISC_STRUCTURE
    1,   // Reserved=0, MediaType=1 (BD)
    0,
    0,
    0,
    0,
    0,
    0, // FormatCode=0 (Disc Information)
    pic_size / 256,
    pic_size % 256,
    0,
    0
  };
  
  int drive = open(drive_filename, 0, O_RDONLY);
  if (drive == -1) {
    fputs("Can't open file\n", stderr);
    return 1;
  }

  unsigned char sense_data[12];

  // Actually there is a lot more than that:
  unsigned char* pic = malloc(pic_size);
  memset(pic, 0, pic_size);

  struct sg_io_hdr header;
  memset(&header, 0, sizeof(header));
  header.interface_id = 'S'; // SCSI
  header.dxfer_direction = SG_DXFER_FROM_DEV;
  header.cmd_len = sizeof(read_pic_command);
  header.mx_sb_len = sizeof(sense_data);
  header.iovec_count = 0;
  header.dxfer_len = pic_size;
  header.dxferp = pic;
  header.cmdp = (unsigned char*) read_pic_command;
  header.sbp = sense_data;
  header.timeout = 60 * 1000;
  header.flags = 0;
  header.pack_id = 0;
  header.usr_ptr = NULL;
  header.status = 0;
  header.msg_status = 0;
  header.sb_len_wr = 0;
  header.host_status = 0;
  header.driver_status = 0;
  header.resid = 0;
  header.duration = 0;
  header.info = 0;

  if (ioctl(drive, SG_IO, &header) < 0) {
    fputs("ioctl failed\n", stderr);
    return 1;
  }

  if ((header.info & SG_INFO_OK_MASK) != SG_INFO_OK) {
    fputs("SCSI command failed\n", stderr);
    return 1;
  }

Here's the result for "The Last Of Us":

00000000: 1002 0000 4449 0110 0000 2000 4244 4f01  ....DI.... .BDO.
00000010: 2101 0300 0000 0000 019a f5bf 0010 0000  !...............
00000020: 00ca 73fe 0000 0000 0000 0000 0000 0000  ..s.............
00000030: 0000 0000 0000 0000 0000 0000 0000 0000  ................
00000040: 0000 0000 4449 0111 0001 2000 4244 4f01  ....DI.... .BDO.
00000050: 2101 0300 0000 0000 019a f5bf 0135 8c00  !............5..
00000060: 01ef fffe 0000 0000 0000 0000 0000 0000  ................
00000070: 0000 5b

References

• 3k3y IsoTools, this is a .NET program available in binary form. The ILspy decompiler produces a very readable output.
• PS3 ISO Patcher by BlackDaemon, is a .NET program available in source code