PKG files

For more information, see Discussion

Package Structure

File Header

While most of the PS4 is little endian, the package file header still uses big endianness as the headers are based on their PS3 predecessors.

 typedef struct {
   uint32_t pkg_magic;          // 0x000
   uint16_t pkg_revision;       // 0x004
   uint16_t pkg_type;           // 0x006
   uint32_t pkg_unk;            // 0x008 - unknown field
   uint32_t pkg_file_count;     // 0x00C
   uint32_t pkg_entry_count;    // 0x010
   uint16_t pkg_sc_entry_count; // 0x014
   uint16_t pkg_entry_count_2;  // 0x016 - same as pkg_entry_count
   uint32_t pkg_table_offset;   // 0x018 - file table offset
   uint32_t pkg_ent_data_size;  // 0x01C
   uint64_t pkg_body_offset;    // 0x020 - offset of PKG entries
   uint64_t pkg_body_size;      // 0x028 - length of all PKG entries
   

   unsigned char pkg_padding[0x10];         // 0x030 - 16 bytes padding
   unsigned char pkg_content_id[0x24];      // 0x040 - packages' content ID as a 36-byte string
   unsigned char pad[0xC];                  // 0x064 - 0x070 - padding
   uint32_t pkg_drm_type;                   // 0x070 - DRM type
   uint32_t pkg_content_type;               // 0x074 - Content type
   // other stuff... 0x78 - 0x100
   

   /* Digest table */
   unsigned char digest_entries1[0x20];     // 0x100 - sha256 digest for main entry 1
   unsigned char digest_entries2[0x20];     // 0x120 - sha256 digest for main entry 2
   unsigned char digest_table_digest[0x20]; // 0x140 - sha256 digest for digest table
   unsigned char digest_body_digest[0x20];  // 0x160 - sha256 digest for main table
   // ... 0x180 - 0x400
   uint32_t pfs_image_count;                // 0x404 - count of PFS images
   uint64_t pfs_flags;                      // 0x408 - PFS flags
   uint64_t pfs_image_offset;               // 0x410 - offset to start of external PFS image
   uint64_t pfs_image_size;                 // 0x418 - size of external PFS image
   // ...
 } pkg_header;

Files

The file table is a list of file entries:

 typedef struct {
   uint32_t id;               // File ID, useful for files without a filename entry
   uint32_t filename_offset;  // Offset into the filenames table (ID 0x200) where this file's name is located
   uint32_t flags1;           // Flags including encrypted flag, etc
   uint32_t flags2;           // Flags including encryption key index, etc
   uint32_t offset;           // Offset into PKG to find the file
   uint32_t size;             // Size of the file
   uint64_t padding;          // blank padding
 } pkg_table_entry;

Some of the files listed in the table with filenames include:

param.sfo - contains information critical to the app / game
playgo-chunk.dat - contains data regarding playgo (see Playgo)
playgo-chunk.sha - contains hash of playgo (see Playgo)
playgo-manifest.xml - contains manifest for playgo (see Playgo)
pronunciation.xml - contains word definitions for PS4's voice recognition software
pronunciation.sig - signature of definition file
pic0.png - small game preview icon
pic1.png - large game preview icon
icon0.png - small icon
icon1.png - large icon

There are also files without plaintext filenames. These are identified by their ID in the file entry table.

PFS

Main article: PFS (only explains un-encrypted, un-signed PFS)

The main portion of a PKG file is its signed and encrypted PFS image. It is encrypted with XTS-AES with a block size of 0x1000. The key is derived from the HMAC-SHA256 of the concatenation of "0x01 0x00 0x00 0x00" in and the EKPFS. The HMAC key is the "crypt seed" which is at offset 0x370 in the PFS itself. The tweak key is the first 16 bytes of the HMAC result, while the data key is the second 16 bytes.

The PFS image in a PKG is different from the decrypted image exposed by the system in /mnt/sandbox/pfsmnt/CUSA00001-app0-nest/pfs_image.dat. This image uses dinode_s32, the signed inode variant, which includes a 32-byte signature for every direct and indirect block. Additionally, the indirect block blocks also have a 32-byte signature for each block within.

Inside the PFS image in a PKG is a single file: pfs_image.dat which is a special type of compressed PFS image with a PFSC header. Inside pfs_image.dat is where the actual game/theme/DLC data lives.

Delivery

Title XML

The PS4 fetches information about pkg files (including where to download them) from an XML file. This XML file contains information such as if the latest patch is mandatory, the latest package version, the manifest, as well as param.sfo information. Below is an example of a typical title XML file:

<titlepatch titleid="CUSAXXXXX">
 <tag name="37" mandatory="true">

  <package version="01.xx" size="" digest="" manifest_url="" content_id="" system_ver="" type="cumulative" remaster="false" patchgo="true">
   <delta_info_set url="" />

   <paramsfo>
    <title></title>
    ...
   </paramsfo>
  </package>

  <latest_playgo_manifest url="" />
 </tag>
</titlepatch>

Notes:

• The 'size' attribute of the 'package' node is in bytes
• The 'system_ver' attribute of the 'package' node should be converted to hexadecimal for system firmware version
• The 'delta_info_set' node may or may not be present depending on the package

Manifest

It should be noted that PS4 package files have a maximum size of 4GB (or 4096MB), therefore large (most) games are split into chunks or pieces. This is kept track of in the manifest file, which contains json fields which document things such as the size of the final package after the chunks are spliced together, the digest of the final package, the number of chunks, as well as information for each chunk such as the pkg url, offset for splicing, size of the file, and the sha1 hash value of the individual chunk.

originalFileSize: [size]
packageDigest: "[sha256 digest]"
numberOfSplitFiles: [num]

pieces:
 [n]:
  url: "[url of pkg chunk]"
  fileOffset: [offset]
  fileSize: [size, often 4294967296 until last chunk]
  hashValue: "[sha1 hash of chunk]"

Sample Packages

Apps/Games

• Amazon/LOVEFiLM App

http://gs2.ww.prod.dl.playstation.net/gs2/appkgo/prod/CUSA00126_00/1/f_012ccf9936265867696e3906c9bd9f0fd1869111fa372b2d1fad0ca4127ba67b/f/EP4183-CUSA00126_00-AIV00000000000EU.pkg

• Headset Begleit-App

http://gs2.ww.prod.dl.playstation.net/gs2/appkgo/prod/CUSA00468_00/2/f_2e42a175df474235aa4e1fd5e5b6fe744433ce5165a109d9f25e8a56cc2dae02/f/EP9000-CUSA00468_00-HEADSETCOMPANION.pkg

• IGN App

http://gs2.ww.prod.dl.playstation.net/gs2/appkgo/prod/CUSA00268_00/2/f_d505314f45cf63825aba7b0d12e8d4d11248d43cb9da25ade13319a4dfc0835d/f/EP4436-CUSA00268_00-WEBMAF0000000IGN.pkg

• Maxdome App

http://gs2.ww.prod.dl.playstation.net/gs2/appkgo/prod/CUSA00115_00/5/f_ce26675e7d8ea8a746486ebe08772d680a597603293b866a1ac79efc519362eb/f/EP4374-CUSA00115_00-MAXDOMEFULLAPP00.pkg

• Netflix App

http://gs2.ww.prod.dl.playstation.net/gs2/appkgo/prod/CUSA00127_00/1/f_7ebe28278e8c18913cb0118bdb960e852d44aec490c238e74e899749c793cbaf/f/EP4350-CUSA00127_00-NETFLIXPOLLUX001.pkg

• SingStar App

http://gs2.ww.prod.dl.playstation.net/gs2/appkgo/prod/CUSA00033_00/3/f_3228ceaa0d67c882a7d21d67790e1216dd6dd1a5c69e93a3d6bf6edb46bcaca2/f/EP9000-CUSA00033_00-SINGSTARE3XX2013.pkg

• VidZone App

http://gs2.ww.prod.dl.playstation.net/gs2/appkgo/prod/CUSA00235_00/5/f_6e74c11865320274ad56655f051502a3935bf33de4af448a268cac707e50025a/f/EP4071-CUSA00235_00-0000000000000000.pkg

• YouTube App

http://gs2.ww.prod.dl.playstation.net/gs2/appkgo/prod/CUSA01116_00/3/f_46f1700767dd845e919dd18aeb8fc1e96c4ba8ac6053b75f5ff3a0b8745d524a/f/EP4381-CUSA01116_00-YOUTUBESCEE00000.pkg

Themes

• 20th Anniversary Dynamic Theme

http://gs2.ww.prod.dl.playstation.net/gs2/acpkgo/prod/CUSA01501_00/5/f_3074fd8eb8322540c8742865a722c6773b031f68d517df3e18d7037fe58af7b0/f/EP9000-CUSA01501_00-20THANNITHEME001.pkg

• AR-Roboter Dynamic Theme

http://gs2.ww.prod.dl.playstation.net/gs2/acpkgo/prod/CUSA00001_00/13/f_aef3a991112dfa798166c951f32b20870b1313f586bdc7788678ba6659671259/f/IP9100-CUSA00001_00-PLAYROOM0THEME01.pkg

• Rechtecke Dynamic Theme

http://gs2.ww.prod.dl.playstation.net/gs2/acpkgo/prod/CUSA01501_00/3/f_65216ee84a210c1541f395558498b451952b1a81fd4a9a0ae77e32b97aeb6122/f/EP9000-CUSA01501_00-0000000000000002.pkg

• Papierskulptur Dynamic Theme

http://gs2.ww.prod.dl.playstation.net/gs2/acpkgo/prod/CUSA01501_00/2/f_fc5c05478edf8847dc118d07225d6e58c630f088f5eae4d0559c88bdda674de6/f/EP9000-CUSA01501_00-0000000000000001.pkg

• Spiralen Dynamic Theme

http://gs2.ww.prod.dl.playstation.net/gs2/acpkgo/prod/CUSA01501_00/1/f_a6fb07c75a9776ca2f71e557a98620318bf11378c69d812f147c9f0fe12ee1c6/f/EP9000-CUSA01501_00-0000000000000003.pkg

Source: https://boerse.to/thema/datenbank-fuer-ps4-psn-links.1979635/

See also: PKG_files/rawlist1, PKG_files/rawlist2