Editing NPD

NPD is a packet format used on PS3 in [[NPDRM]] contents. It corresponds to 2 sort of packets: the ones in SDAT/[[EDAT files]] and the ones in [[SELF_-_SPRX#Supplemental_Header_Table|SELF/SPRX NPDRM header]] in [[NPDRM]] SELF/SPRX files only. NPD likely stands for Network Playstation Data or Network Playstation Drm. PS Vita equivalent is "DRM".

= Location =

NPD packets are stored in [[EDAT files]] and in [[NPDRM]] [[SELF - SPRX]] files.

= Structure =

{| class="wikitable" style="text-align: center;"
|-
! Offset !! Name !! Size !! Type !! Notes
|-
| 0x00 || Magic || 4 || char[4] ||"NPD\0" (4E 50 44 00)
|-
| 0x04 || Version || 4 || uint32_t || ex: 1, 2, 3, 4. See [[EDAT_files#Footer]] for the precise NPD packager version.
|-
| 0x08 || [[NPDRM#DRM Type|DRM Type]] || 4 || uint32_t || For PS2 EDAT, PS3 FW requires it to be with activation (i.e. Local DRM). For [[PKG_files#Misc.2FNote|PS1 PKG]], PS3 FW 4.00 introduced some changes for installing them with regard to the EDAT DRM type.
|-
| 0x0C || [[App Types|Application Type]] || 4 || uint32_t ||
|-
| 0x10 || [[PARAM.SFO#CONTENT_ID|CONTENT ID]] || 0x30 || uint8_t[0x30] || Content ID (with padding to fit 48 bytes)
|-
| 0x40 || Digest || 0x10 || uint8[0x10] || QA digest. It seems to be a SHA-1 hash of the non-finalized file (debug self/sprx created with make_fself_npdrm) or of the original EDAT data. Original data are unknown until the whole file is read, so it cannot be used as a check, however it can be used as watermark or zeroed on forged file.
|-
| 0x50 || NPD CID-FN Hash || 0x10 || uint8_t[0x10] || CID-FN hash. AES-CMAC hash of concatenation of Content ID (48 bytes) and EDAT/SELF filename (eg "MINIS.EDAT", "EBOOT.BIN") using the [[Keys#NPDRM_Keys|CID-FN hash AES-CMAC key]]. Example: aes_cmac(55 50 30 35 37 36 2D 4E 50 55 5A 30 30 31 34 39 5F 30 30 2D 56 41 4E 47 55 41 52 44 32 30 30 30 30 30 30 31 00 00 00 00 00 00 00 00 00 00 00 00 4D 49 4E 49 53 2E 45 44 41 54, npd_cid_fn_hash_aes_cmac_key).
|-
| 0x60 || NPD Header hash || 0x10 || uint8_t[0x10] || Header hash. AES CMAC hash of the 0x60 bytes from the beginning of the file using (klicensee XOR [[Keys#NPD_Header_Hash_XOR_Key|npd_header_hash_xor_key]]) as AES-CMAC key.
|-
| 0x70 || Activation time || 8 || ?64-bit time or with 32-bit padding? || Start of the validity period, filled with 00 if not used.
|-
| 0x78 || Expiration time || 8 || ?64-bit time or with 32-bit padding? || End of the validity period, filled with 00 if not used.
|}

<source lang="C">
typedef struct PS3_NPD { //size is 0x80 bytes
  uint32_t magic; // 4E 50 44 00 ("NPD.")
  uint32_t version;
  uint32_t drm_type;
  uint32_t app_type;
  uint8_t content_id[0x30];
  uint8_t digest[0x10];
  uint8_t cid_fn_hash[0x10];
  uint8_t header_hash[0x10];
  uint64_t activation_time;
  uint64_t expiration_time;
} PS3_NPD;
</source>

= Tools =

* The main tool to deal with NPD packets is [https://github.com/ErikPshat/make_npdata-hykem/ make_npdata by Hykem].