Editing IDStorage

= Location =

== PSP ==

IDStorage area is located after the IPL on the NAND at offset 0xC0000.

= Description =

It is used to store low-level information, such as the serial, [[MAC address]], [[UMD]], WLAN and region. 

The IDStorage area is an associative array and information is stored using key/value pairs (index/leaf). The IDStorage seems a little coupled to the physical storage as each leaf is mapped to an area of 512-byte, which is equal to the pagesize of the PSP standard NAND flash, and it seems 512-byte page operations are intended.

= Structure =

Idstorage leaves are all 512 bytes. Most IDStorage leaves have a pair, although some do not.

Idstorage leaves indexes are 16-bit integers and are stored in an index table of two NAND pages of 512 bytes.

* The index is identified by byte 6 of the spare area (0x73).
* byte 7 is the idstorage version.
* byte is either 1 or 0 depending on whether the idstorage has been formatted or not, and finally byte 9 indicates if the idstorage is read-only or not.

For example, an index appearing at position 27 (byte 54) in the index table would find its associated data at the NAND offset: 0xC0000 + (27 * 512) = 0xC3600.

= Importance in OS =

As major functions such as UMD decryption, Ad Hoc and DNAS Authentication rely on IDStorage leaves, the loss or corruption of leaves can be crippling to the usability of the PSP. Users are strongly recommended to take a [[NAND Backup]], giving them the opportunity to restore their IDStorage using a tool such as [[NandTool]].

The firmware provides a driver to facilitate manipulations. In PSP: idstorage.prx. In PSVita: idstorage.skprx.

= Generation =

Most of the idstorage generation process is detailed in Despertar Del Cementerio (sources available here: https://github.com/mathieulh/Despertar-Del-Cementerio).

* some PSP JigKick files contain information on how to (re)generate idstorage leaves
* DespertarDelCementerio v7 also contains information about idstorage (re)generation.
* the most significant module used by DCv7 used to do this is idsregeneration.prx<br />
(see DCv7 src code https://github.com/mathieulh/Despertar-Del-Cementerio/tree/master/idsregeneration).
* you can see a plethora of "templates" which are used for the generation of the idstorage sections.
* the idstorage regeneration requires 2, probably more parameters -> Region, MAC Address, and likely a timestamp of sorts.
* on ps3 the generation method wasn't found on the JigKick firmware files (and selfs). however, it seems that factory still does this, but by accessing a server, so the information cannot be deduced anymore unless there's access to the server.
* together with the idps (called PSID on PSP), the openPSID is also generated on PSP (written to IdStorage).
* there are 12 sections on PSP, unlike the 11 ones on PS3 EID0.

= IDStorage certified sections =

IDStorage certified sections are a security measure for critical information. For example PSID and OpenPSID are certified (leaves 0x100, 0x101, 0x120, 0x121). For PSPemu on PS3 and PS Vita, the same sort of certificates are contained in PS3 eEID and PS Vita ID Storage, and Kirk commands are implemented to handle them. Moreover, PS3 eEID certificates use almost the same structure and algorithms, whilst PS Vita extends block sizes from 128 to 192 and 256 bits.

Kirk command 0x12 is used to verify IDStorage certificates.

== Structure ==

{|class="wikitable"
|-
! Name !! Size !! Description
|-
| Data || 0x10 || contains the actual data (either PSID or OpenPSID)
|-
| plaintext public key || 0x28 || contains the certificate's public key (without padding)
|-
| R || 0x14 || part of the ECDSA signature pair (R, S)
|-
| S || 0x14 || part of the ECDSA signature pair (R, S)
|-
| public key || 0x28 || ECDSA public key (unknown what this is doing here)
|-
| encrypted private key || 0x20 || encrypted blob that contains the certificate's private key (with padding)
|-
| omac/cmac1 || 0x10 || hash of the previous information in CMAC1/OMAC mode
|}

<source lang="C">
typedef struct ECDSA160_signature { // size is 0x28
   unsigned char r[0x14];
   unsigned char s[0x14];
} ECDSA160_signature;

typedef struct ids_cert_main_psp { // size is 0xA8
char data[0x10];
char pub_key[0x28]; // ?generated using Kirk command 0xC? sent to Kirk command 0x11 for verification
ECDSA160_signature signature;
char constant_pub_key[0x28]; // hardcoded constant, same in all PSP consoles but depends on the certificate index in ID Storage
char enc_priv_key[0x20]; // decrypted and verified by Kirk command 0x10
} ids_cert_main_psp;

typedef struct ids_cert_psp { // size is 0xB8
ids_cert_main_psp cert_data; // data input for generating enc_aes_cmac_hash
char aes_cmac[0x10]; // verified by Kirk command 0x12
} ids_cert_psp;
</source>

= Content =

* Leaves 0x100-0x11F are identical to their backup leaves 0x120-0x13F
* Old PSP revision haven't leaves 0x046, 0x047
* Very old PSP revisions haven't leaf 0x140
* Leaf 0x50 is maybe Serial Number

= Uses =

== IPL ==

The Stage 2 [[IPL]] (main.bin) reads 3 leaves, 0x004, 0x005 and 0x006. These leaves play a significant part in the PSP as they are related to power. In TA-082 and TA-086 PSP's, these leaves are at different locations, causing a brick with the 1.50 IPL.

0x004
 0000000000  6E 79 72 42 01 00 00 00-10 00 00 00 BB 01 AB 1F  nyrB............
 0000000016  D8 00 24 00 14 31 14 00-94 01 48 00 D8 00 00 00  ..$..1....H.....

0x005
 0000000000  67 68 6C 43 01 00 00 00-01 00 00 00 CA D9 E3 9B  ghlC............
 0000000016  0A 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00  ................

0x006
 0000000000  72 64 44 4D 01 00 00 00-07 00 00 00 85 BD 2C 75  rdDM..........,u
 0000000016  00 00 00 85 83 81 80 00-00 00 00 00 00 00 00 00  ................

== Chkreg.prx ==

=== sceChkregGetPsCode ===

Chkreg (chkreg.prx) reads 2 leaves, 0x100 and 0x102 or 0x120 and 0x122. 

It gets PSID from the IdStorage and convert it to PsCode.

Example of PSP PsCode: 00 00 00 01 00 03 00 01

The return from sceChkregGetPsCode is determined to be valid or invalid via KIRK command 0x12, just like other functions using leaves 0x100, 0x120.

== openpsid.prx ==

=== sceOpenPSIDGetPSID ===

sceOpenPSIDGetPSID first reads leaf 0x100 or 0x120 into a buffer using sceIdStorageLookup with the following args:

 sceIdStorageLookup(0x120, 0x38, buf, 0xB8); // ???offset to check???

The buffer is then sent to KIRK using sceUtilsBufferCopyWithRange with the following args:

 sceUtilsBufferCopyWithRange(0, 0, buf, 0xB8, 0x12);

It sends data to 2 modules: OpenPSID and memab. Once the scrambled buffer has been sent, "some check" is performed.

If sceUtilsBufferCopyWithRange is sucessful, this part of sceChkregGetPsCode returns 0, else it returns 0x80000108.

=== sceOpenPSIDGetOpenPSID ===

OpenPSID (openpsid.prx) reads 2 leaves, both relating to the region: 0x101 or 0x121 and 0x102 or 0x122. The OpenPSID is calculated via the above leaves and sceUtilsBufferCopyWithRange.

It first reads 0x101 or 0x121 into a buffer. If this fails it returns 0xC0520001 and reads 0x102 or 0x122 into the buffer. If it fails again, it returns 0xC0520002.

The buffer is then passed to sceUtilsBufferCopyWithRange with the following args:

 sceUtilsBufferCopyWithRange(0, 0, buf, 0xB8, 0x12);

If the sceUtilsBufferCopyWithRange returns 1, OpenPSID returns 0xC0520001, else it returns 0.

== Memab ==

Memab (memab.prx) reads 1 leaf, 0x100 or 0x120.

Mgr (mgr.prx) reads 2 leaves, 0x040 and another unknown leaf.

0x040
 00000001E0  03 86 00 20 F8 47 90 88-58 99 2E 88 F8 47 90 88  ... .G..X....G..
 00000001F0  25 00 00 00 64 99 2E 88-01 00 00 00 D0 99 2E 88  %...d...........

Another unknown leaf.

== Power ==

Power (power.prx) reads 1 leaf, 0x0004. This leaf is related to power and is also read by the IPL.

== Umdman ==

Umdman (umdman.prx) reads 5 leafs, 0x102, 0x103, 0x104, 0x105, 0x106, 0x107. The leaf 0x102 is related to the region, and is probably used to determine what UMD video's can be read on the PSP.

== USB ==

=== usb.prx ===

USB (usb.prx) reads 1 leaf, 0x041. This leaf has information on the USB types.

0x041
 0000000000  4C 05 00 00 0A 03 53 00-6F 00 6E 00 79 00 00 00  L.....S.o.n.y...
 0000000064  00 00 00 00 05 00 00 00-C8 01 00 00 16 03 50 00  ..............P.
 0000000080  53 00 50 00 20 00 54 00-79 00 70 00 65 00 20 00  S.P. .T.y.p.e. .
 0000000096  41 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00  A...............
 0000000128  00 00 00 00 00 00 00 00-00 00 00 00 C9 01 00 00  ................
 0000000144  16 03 50 00 53 00 50 00-20 00 54 00 79 00 70 00  ..P.S.P. .T.y.p.
 0000000160  65 00 20 00 42 00 00 00-00 00 00 00 00 00 00 00  e. .B...........
 0000000208  CA 01 00 00 16 03 50 00-53 00 50 00 20 00 54 00  ......P.S.P. .T.
 0000000224  79 00 70 00 65 00 20 00-43 00 00 00 00 00 00 00  y.p.e. .C.......
 0000000272  00 00 00 00 CB 01 00 00-16 03 50 00 53 00 50 00  ..........P.S.P.
 0000000288  20 00 54 00 79 00 70 00-65 00 20 00 44 00 00 00   .T.y.p.e. .D...
 0000000336  00 00 00 00 00 00 00 00-CC 01 00 00 16 03 50 00  ..............P.
 0000000352  53 00 50 00 20 00 54 00-79 00 70 00 65 00 20 00  S.P. .T.y.p.e. .
 0000000368  45 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00  E...............

 Offset  Description                   Data
 0x0000  idVendor                      0x4C 0x05                             
 0x0002  ???                           0x00 0x00                             
 0x0004  bLength                       0x0A                                  
 0x0005  ???                           0x03                                  
 0x0006  iManufacturer String          0x53 0x00 0x6F 0x00 0x6E 0x00 0x79    
 0x0044  ? bNum                        0x05                                  
 0x0045  ???                           0x00 0x00 0x00                        
 0x0048  idProduct                     0xC8 0x01                             
 0x004A  ???                           0x00 0x00                             
 0x004C  bLength                       0x16                                  
 0x004D  ? bDescriptorType             0x03                                  
 0x004E  iProduct String               0x50 0x00 0x53 0x00 0x50 0x00 0x20    
                                       0x00 0x54 0x00 0x79 0x00 0x70 0x00    
                                       0x65 0x00 0x20 0x00 0x41              
 0x008C  idProduct                     0xC9 0x01                             
 0x008E  ???                           0x00 0x00                             
 0x0090  bLength                       0x16                                  
 0x0091  ? bDescriptorType             0x03                                  
 0x0092  iProduct String               0x50 0x00 0x53 0x00 0x50 0x00 0x20    
                                       0x00 0x54 0x00 0x79 0x00 0x70 0x00    
                                       0x65 0x00 0x20 0x00 0x42              
 0x00D0  idProduct                     0xCA 0x01                             
 0x00D2  ???                           0x00 0x00                             
 0x00D4  bLength                       0x16                                  
 0x00D5  ? bDescriptorType             0x03                                  
 0x00D6  iProduct String               0x50 0x00 0x53 0x00 0x50 0x00 0x20    
                                       0x00 0x54 0x00 0x79 0x00 0x70 0x00    
                                       0x65 0x00 0x20 0x00 0x43              
 0x0114  idProduct                     0xCB 0x01                             
 0x0116  ???                           0x00 0x00                             
 0x0118  bLength                       0x16                                  
 0x0119  ? bDescriptorType             0x03                                  
 0x011A  iProduct String               0x50 0x00 0x53 0x00 0x50 0x00 0x20    
                                       0x00 0x54 0x00 0x79 0x00 0x70 0x00    
                                       0x65 0x00 0x20 0x00 0x44              
 0x0158  idProduct                     0xCC 0x01                             
 0x015A  ???                           0x00 0x00                             
 0x015C  bLength                       0x16                                  
 0x015D  ? bDescriptorType             0x03                                  
 0x015E  iProduct String               0x50 0x00 0x53 0x00 0x50 0x00 0x20    
                                       0x00 0x54 0x00 0x79 0x00 0x70 0x00    
                                       0x65 0x00 0x20 0x00 0x45

=== usbstor.prx ===

USBstor (usbstor.prx) reads 1 leaf, ?0x040 or 0x043?.

?0x040 or 0x043?
 0000000000  55 73 74 72 53 6F 6E 79-20 20 20 20 50 53 50 20  UstrSony    PSP 
 0000000016  20 20 20 20 20 20 20 20-20 20 20 20 31 2E 30 30              1.00
 0000000032  50 00 53 00 50 00 00 00-00 00 00 00 00 00 00 00  P.S.P........... 

== WLAN ==

WLAN (wlan.prx) reads 2 leaves, 0x044 and 0x045.

0x044
 0000000000  00 16 FE 86 FA 28                                .....(          

0x045
 0000000000  03 00 01                                         ...             

These leaves contains the MAC address of the PSP. This can be changed, but does not effect the hardware, only the address displayed under System Information.

== Sysconf_plugin ==

Sysconf_plugin (sysconf_plugin.prx) reads 1 leaf, 0x044. This is probably why the VSH displays a different MAC address when leaves 0x044/0x045 are changed.

== Vshmain ==

Vshmain (vshmain.prx) reads 1 leaf, 0x046.

0x046
 Empty, however vshmain uses the first byte of this leaf to set a param for vshImposeSetParam. 

= Legality of distribution =

There is question as to whether [[Sony]] are able to take legal action against those found to be distributing IDStorage leaves among the community, for research, repair, or otherwise. The worry is that the leaves are proprietary data (particularly UMD decryption leaves).

= Useful links =

* [https://github.com/esxgx/uofw/blob/master/src/lowio/nand.c]
* [https://gigawiz.github.io/yapspd/html_chapters_split/chap19.html#sec19.2.4]
* [https://xero1.wordpress.com/2007/01/06/hello-world/]
* [https://www.elotrolado.net/hilo_referencia-sobre-el-idstorage_839995]