ScePfsMgr

Module

Known NIDs

Version	Name	World	Privilege	NID
1.69	ScePfsMgr	Non-secure	Kernel	0x3CF10F0
3.60	ScePfsMgr	Non-secure	Kernel	0x538BA86B

Libraries

Known NIDs

Version	Name	World	Visibility	NID
1.69-3.60	ScePfsMgrForKernel	Non-secure	Kernel	0xA067B56F
3.60	ScePfsFacadeForKernel	Non-secure	Kernel	0xC26DC7BD

Types

struct pmi_blc_subctx
{
  pmi_blc_subctx *subctx0;
  pmi_blc_subctx *subctx4;
  SceUInt64 auth_ids[16];
  vfs_block_dev_info block_dev;
  uint32_t num_authids;
};

union pfs_pmi_buffer_list_ctx_u0
{
  buffer_list *blist;
  int some_flags;
};

struct pfs_pmi_buffer_list_ctx
{
    pfs_pmi_buffer_list_ctx_u0 unk_0;
    uint32_t unk_4;
    SceUID ScePfsPmi_mutex_id; // 0x08
    char original_path[0x40];  // 0xC
    
    char rnd_drive_id1[0x22]; // 0x4C - "/%s"
    
    char rnd_drive_id2[0x24];  // 0x6E - "%s0:" - used for pfs_pmi_buffer_list_ctx lookup on mount

    uint16_t mode_index;   //0x92
    uint16_t crypto_engine_flag; //0x94 = 0
    
    char klicensee[0x10]; //0x96
    
    uint16_t key_id;
    uint32_t files_salt;
    uint32_t unk_AC; // = 0
    
    SceUID ScePfsFilesDb_mutex_id; // 0xB0
    
    char unk_data1[0xBC]; // 0xB4
    
    pmi_blc_subctx subctx;
    
    //further fields are unknown
} pfs_pmi_buffer_list_ctx;

struct buffer_list
{
    SceUID mutex_id;
    uint32_t unk_4;
    uint32_t unk_8;
    uint32_t unk_C;
    uint32_t unk_10;
    void* blc; //0x14 - one of versions is pfs_pmi_buffer_list_ctx
}buffer_list;


typedef struct CryptEngineData //size is 0x60
{
   uint32_t unk_0;
   uint32_t unk_4;
   uint32_t unk_8;
   uint16_t unk_C;
   uint16_t flag; // 0xE - flag that selects decryption type ?
   
   uint16_t key_id; //0x10
   uint16_t seed1_base; //iv seed
   
   uint32_t unk_14;
   uint32_t unk_18;
   uint32_t unk_1C;
   
   uint32_t unk_20;
   uint32_t unk_24;
   uint32_t size1;
   char key[0x10]; //0x2C
   
   char iv_xor_key[0x10]; //0x3C
   
   char hmac_key[0x14]; //0x4C

}CryptEngineData;

typedef struct CryptEngineSubctx //size is 0x58
{
   uint32_t unk_0;
   uint32_t unk_4;
   uint32_t opt_code; // 0x8 - if 3 then decrypt, if 4 then encrypt, if 2 then encrypt
   CryptEngineData* data; // 0xC
   
   uint32_t unk_10;
   uint32_t source; // 0x14
   uint32_t unk_18;
   uint32_t unk_1C;
   
   uint32_t unk_20;
   uint32_t unk_24;
   uint32_t size2; //0x28
   uint32_t nDigests; // 0x2C - also digest table index
   
   uint32_t unk_30;
   uint32_t seed0_base; // 0x34
   uint32_t dest_offset; // 0x38
   uint32_t size0; // 0x3C
   
   uint32_t size1;
   uint32_t unk_44;
   uint32_t size3; //0x48
   char* hmac_sha1_digest; // digest to verify (possibly table)
   
   void* buffer0; // 0x50
   void* buffer1; // 0x54
   
}CryptEngineSubctx;

typedef struct CryptEngineWorkCtx //size is 0x18
{
   void* unk_0; // pointer to data 0x140 + 0x18 ?
   void* unk_4; // pointer to data 0x140 + 0x18 ?
   CryptEngineSubctx* subctx; // 0x8
   uint32_t error; //set to 0 or error code after executing crypto task
   
   SceUID threadId; // = set with sceKernelGetThreadIdForDriver. used with ksceKernelSignalCondTo
   uint32_t unk_14;
   
}CryptEngineWorkCtx;

Data segment layout

Address	Size	Description
0x0000	0x20	vfs_add_data PFS_REDIRECT_INF node (Redirect Pseudo Drive.)
0x0020	0x20	vfs_add_data PFS_GDSD_INF node (Gamedata/Savedata Pseudo Drive.)
0x0040	0x20	vfs_add_data PFS_AC_INF node (AC Pseudo Drive.)
0x0060	0x20	unknown
0x0080	0x4	mutex SceUID ScePfsFiBufferList
0x0084	0x4	memblock SceUID ScePfsFiBufferList
0x0088	0x4	char* ScePfsFiBufferList
0x008C	0x4	some offset or size
0x0090	0x4	some offset or size
0x0094	0x4	void*
0x0098	0x4	mutex SceUID ScePfsVdBufferList
0x009C	0x4	memblock SceUID ScePfsVdBufferList
0x00A0	0x4	char* ScePfsVdBufferList
0x00A4	0x4	some offset or size
0x00A8	0x4	some offset or size
0x00AC	0x4	void*
0x00B0	0x4	mutex SceUID ScePfsLruPoolBufferList
0x00B4	0x4	memblock SceUID ScePfsLruPoolBufferList
0x00B8	0x4	char* ScePfsLruPoolBufferList
0x00BC	0x4	some offset or size
0x00C0	0x4	some offset or size
0x00C4	0x4	void*
0x00C8	0x4	mutex SceUID ScePfsLruTblHdrBufferList
0x00CC	0x4	memblock SceUID ScePfsLruTblHdrBufferList
0x00D0	0x4	char* ScePfsLruTblHdrBufferList
0x00D4	0x4	some offset or size
0x00D8	0x4	some offset or size
0x00DC	0x4	void*
0x00E0	0x20	unknown
0x0100	0x10	CMAC buffer used in ScePfsCryptEngineThread subroutines
0x0110	0x4	mutex SceUID ScePfsThePmi
0x0114	0x4	unknown
0x0118	0x4	pfs_pmi_buffer_list_ctx* root
0x011C	0x4	unknown
0x0120	0x4	buffer_list* with mutex SceUID ScePfsPmiBufferList
0x0124	0x4	memblock SceUID ScePfsPmiBufferList
0x0128	0x4	char* ScePfsPmiBufferList
0x012C	0x4	some offset or size
0x0130	0x4	some offset or size
0x0134	0x4	void*
0x0138	0x4	unknown
0x013C	0x4	unknown
0x0140	0x4	0
0x0144	0x4	thread SceUID ScePfsCryptEngineThread
0x0148	0x4	mutex SceUID ScePfsCryptEngineTodoMtx
0x014C	0x4	cond SceUID ScePfsCryptEngineTodoCnd
0x0150	0x4	mutex SceUID ScePfsCryptEngineDoneMtx
0x0154	0x4	cond SceUID ScePfsCryptEngineDoneCnd
0x0158	0x4	pointer to 0x158
0x015C	0x4	pointer to 0x158
0x0160	0x4	pointer to 0x160
0x0164	0x4	pointer to 0x160
0x0168	0x9D8	unknown
0x0B40	0xC0	data chunk of size 0xC0
0x0C00	180	unknown
0x0D80	0x4	mutex SceUID ScePfsCryptBufMutexVC
0x0D84	0x4	mutex SceUID ScePfsCryptBufMutexRM
0x0D88	0x4	mutex SceUID ScePfsCryptBufMutexEMMC
0x0D8C	0x4	memblock SceUID ScePfsCryptBufVC - size 0x40000
0x0D90	0x4	memblock SceUID ScePfsCryptBufVCForShared
0x0D94	0x4	memblock base of ScePfsCryptBufVC
0x0D98	0x4	memblock base of ScePfsCryptBufVCForShared
0x0D9C	0x4	0x000000FF
0x0DA0	0x4	memblock SceUID ScePfsCryptBufRM - size 0x40000
0x0DA4	0x4	memblock SceUID ScePfsCryptBufRMForShared
0x0DA8	0x4	memblock base of ScePfsCryptBufRM
0x0DAC	0x4	memblock base of ScePfsCryptBufRMForShared
0x0DB0	0x4	0x000000FF
0x0DB4	0x4	memblock SceUID ScePfsCryptBufEMM - size 0x40000
0x0DB8	0x4	memblock SceUID ScePfsCryptBufEMMCForShared
0x0DBC	0x4	memblock base of ScePfsCryptBufEMM
0x0DC0	0x4	memblock base of ScePfsCryptBufEMMCForShared
0x0DC4	0x4	0x000000FF
0x0DC8	0x4	cond SceUID ScePfsCryptBufCondVarVC
0x0DCC	0x4	cond SceUID ScePfsCryptBufCondVarRM
0x0DD0	0x4	cond SceUID ScePfsCryptBufCondVarEMMC

Decryption process

Crypto engine

ScePfsMgr heavily uses crypto API from SceSblSsMgrForDriver.

There is a separate thread in ScePfsMgr that is called ScePfsCryptEngineThread.

Almost all calls to the crypto API are done from this single thread.

ScePfsMgr uses a crypto task dispatch mechanism based on mutexes and conditions.

It uses a CryptEngineWorkCtx structure for dispatching the task.

Pointer to that structure is written at offset 0x158 of data section (this needs confirmation).

For dispatching the task ScePfsMgr uses subroutine located at offset 0xBD88.

When task is dispatched ScePfsCryptEngineTodoMtx mutex is locked, ScePfsCryptEngineTodoCnd condition is signaled, ScePfsCryptEngineTodoMtx is unlocked.

For waiting till task is completed ScePfsMgr uses subroutine located at offset 0xBEA0.

Then ScePfsCryptEngineDoneMtx mutex is locked, wait happens on ScePfsCryptEngineDoneCnd condition, ScePfsCryptEngineDoneMtx mutex is unlocked.

Meanwhile ScePfsCryptEngineThread runs.

It locks ScePfsCryptEngineTodoMtx mutex, waits for ScePfsCryptEngineTodoCnd condition, unlocks ScePfsCryptEngineTodoMtx mutex.

When task is finished ScePfsCryptEngineThread locks ScePfsCryptEngineDoneCnd mutex, signals ScePfsCryptEngineDoneCnd to specific thread, unlocks ScePfsCryptEngineDoneCnd mutex.

Thread id for signaling ScePfsCryptEngineDoneCnd is stored in CryptEngineWorkCtx.

VFS node functions

Dispatching mechanism is used only by VFS node functions.

Nodes that are used:

• PFS_GDSD_INF
• PFS_AC_INF

Node functions that are used:

• 5 - sceIoReadForDriver
• 6 - sceIoWriteForDriver
• 16 - sceIoChstatForDriver
• 19 - sceIoPreadForDriver
• 20 - sceIoPwriteForDriver
• 26 - sceIoChstatByFdForDriver

ScePfsMgrForKernel

scePfsMountForKernel

Version	NID
0.990-3.60	0xA772209C

int scePfsMountForKernel(char* original_path, char* rnd_drive_id, SceUInt64 authid, void *klicensee, uint16_t mode_index);

scePfsMount2ForKernel

Version	NID
0.990-3.60	0x2D48AEA2

int scePfsMount2ForKernel(char *original_path, char *rnd_drive_id, void *klicensee, uint16_t mode_index);

scePfsUnmountForKernel

Version	NID
0.990-3.60	0x680BC384

int scePfsUnmountForKernel(char* rnd_drive_id);

scePfsAcidDirMountForKernel

Version	NID
0.990-3.60	0x4A4A8243

• open mountpoint/dlc_folder directory
• execute ioctl command 0x4402 with klicensee input
• close mountpoint/dlc_folder directory

int scePfsAcidDirMountForKernel(const char *mountpoint, const char *dlc_folder, char *klicensee);

scePfsAcidDirUnmountForKernel

Version	NID
0.990-3.60	0x00C8AF80

• open mountpoint/dlc_folder directory
• execute ioctl command 0x4404
• close mountpoint/dlc_folder directory

int scePfsAcidDirUnmountForKernel(const char *mountpoint, const char *dlc_folder);

scePfsAcidDirApproveForKernel

Version	NID
0.990-3.60	0x8CDA249A

• open mountpoint/dlc_folder directory
• execute ioctl command 0x4403
• close mountpoint/dlc_folder directory

int scePfsAcidDirApproveForKernel(const char *mountpoint, const char *dlc_folder);

scePfsAcidDirSetForKernel

Version	NID
0.990-3.60	0xB0CC0A1A

savedata_ioctl_0x4410

Version	NID
3.60	0x27FB7618

execute 0x4410 command on <device_name>0: get 8 bytes of result

int savedata_ioctl_0x4410(const char *device_name, int *ioctl0_res, int *ioctl1_res);

scePfsApproveForKernel

Version	NID
0.990-3.60	0xD8D0FEE5

• find pfs_pmi_buffer_list_ctx* by mount_point
• check auth ids
• set unk_94 flag

int scePfsApproveForKernel(char *rnd_drive_id, SceUInt64 authid);

ScePfsFacadeForKernel

t_scePfsFacadeReadForDriver

Version	NID
3.60	0xBD5B21F6

This is a thread callback used by SceIofilemgr

This function is not implemented and throws 0x8014231C error

int t_scePfsFacadeReadForDriver(sceIoReadForDriver_args *args);

t_scePfsFacadeWriteForDriver

Version	NID
3.60	0xCB622FFE

This is a thread callback used by SceIofilemgr

int t_scePfsFacadeWriteForDriver(sceIoWriteForDriver_args *args);

t_scePfsFacadePreadForDriver

Version	NID
3.60	0x4238D2D2

This is a thread callback used by SceIofilemgr

int t_scePfsFacadePreadForDriver(sceIoPreadForDriver_args *args);

t_scePfsFacadePwriteForDriver

Version	NID
3.60	0x58E643C5

This is a thread callback used by SceIofilemgr

int t_scePfsFacadePwriteForDriver(sceIoPwriteForDriver_args *args);