SELF

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SELF files are a wrapper around encrypted ELF files. The encrypted header contains keys to decrypt each encrypted ELF program, which are decrypted and loaded individually. Because of this, a copy of the ELF headers and ELF program headers are stored in plain text next to the SCE header.

Authentication ID

Offset 0x80 in the SELF header. SceWebCore has 0x8000 set; the only system app with that flag set.

sceAppMgrConvertVs0UserDrivePath checks the authentication id to limit mount points.

0x2800000000008003 seen used by SceWebCore can only access vs0:data/external/cert/ and vs0:data/external/webcore/

0x2800000000008004 seen used by games and 0x210000101CD20007 seen used by PSM can only access vs0:data/external and vs0:sys/external

Relocations

Offset Size Description
0x0 0x4 Relocation Type
0x4 0x4 Long entry: Addend
0x4 0x4 Short entry: 0-19 = Bits 10-29 of offset, 20-31 = addend
0x8 0x4 Long entry: Offset

Relocations can be of two types: 8 byte "short" entries or 12 byte "long" entries. The relocation code is the same as ARM ELF format.


Segment start = Buffer address of segment indexed at "Patch segment"

Symbol start = Buffer address of segment indexed at "Symbol segment"

Address to patch = segment start + offset

P = address to patch

S = "Symbol segment" == 15 ? 0 : symbol start

A = addend

Relocation Type

Start End Description
0 3 Short entry if set
4 7 Symbol segment
8 15 Relocation code
16 19 Patch segment
20 27 Long entry: Optional relocation code 2
28 31 Long entry: Optional distance 2
20 31 Short entry: Lower 12 bits of offset

Supported Relocation Codes (1.69)

Code Description
0 R_ARM_NONE
2 R_ARM_ABS32
3 R_ARM_REL32
10 R_ARM_THM_CALL
28 R_ARM_CALL
29 R_ARM_JUMP24
38 R_ARM_TARGET1 (same as R_ARM_ABS32)
40 R_ARM_V4BX (same as R_ARM_NONE)
41 R_ARM_TARGET2 (same as R_ARM_REL32)
42 R_ARM_PREL31
43 R_ARM_MOVW_ABS_NC
44 R_ARM_MOVT_ABS
47 R_ARM_THM_MOVW_ABS_NC
48 R_ARM_THM_MOVT_ABS