PSSE: Difference between revisions

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(→‎What is PSSE?: Fix grammar and include reference to said PFS)
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| style="background-color:#FFFFFF; color:#123AAA;" |'''description'''  
| style="background-color:#FFFFFF; color:#123AAA;" |'''description'''  
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|-
|0x00||0x50535345 (ASCII "PSSE")||Magic Number / File Header
|0x00||0x50535345 (ASCII "PSSE" / "PSME")||Magic Number / File Header
|-
|-
|0x14||[[System_File_Object_(SFO)_(PSF)#CONTENT_ID|CONTENT_ID]]||Contents of /RW/System/content_id
|0x4|| int32 || Version
|-
|-
|0x40||Signature||Generated by PSMSDK 'publisher key'? - Similar to sce_sys/[[clearsign]] file of NpDrm-Encrypted apps
|0x8 || int32 || Decrypted file size
|-
|-
|0x180||Encrypted Keys||Generated by PSMSDK 'app key' and 'app seed'? - Similar to sce_sys/[[keystone]] file of NpDrm-Encrypted apps
|0x14|| char[0x24] [[System_File_Object_(SFO)_(PSF)#CONTENT_ID|CONTENT_ID]]||Contents of /RW/System/content_id
|-
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|0x680||Encrypted Data||Actual cipher-text for the encrypted file
|0x70|| char[0x10] ||Encrypted IV AES-128-CBC with (PSSE Header Key and PSSE Header IV)
|-
|0x680||Encrypted Data|| 0x8000 encrypted blocks
|-
|-
|}
|}

Revision as of 11:40, 3 October 2021

What is PSSE?

PSSE stands for PlayStation Suite Encrypted. It is an encryption layer that encrypts the PSM game's filesystem.

The encryption layer is comparable to the PS Vita Filesystem in many ways; however, it seemed that there was a bug at Sony, where besides executable files, the first directory level of a PSM app is not encrypted with PSSE, whose directory level is below the root of RO/. Similarly, the PSM SaveData is not encrypted by such layer either.

Data Structure

offset value description
0x00 0x50535345 (ASCII "PSSE" / "PSME") Magic Number / File Header
0x4 int32 Version
0x8 int32 Decrypted file size
0x14 char[0x24] CONTENT_ID Contents of /RW/System/content_id
0x70 char[0x10] Encrypted IV AES-128-CBC with (PSSE Header Key and PSSE Header IV)
0x680 Encrypted Data 0x8000 encrypted blocks

Decryption

PSSE Can be decrypted using the http://bitbucket.org/SilicaAndPina/FuckPSSE plugin by SilicaAndPina