SELF File Format

ORBIS SELFs from PS4 have a somewhat different structure from the ones we see on vita and ps3. The structure is documented as follows:

SELF Header Structure

Offset	Size	Description	Notes
0	4	Magic	4F 15 3D 1D
0x4	4	Unknown	Always 00 01 01 12
0x8	1	Unknown	Always 1
0x9	1	Key Revision	0xC SK, 0xF SL, 0xE SM, 0x8 EBOOT and ELF and SELF, 0x9 SPRX and SDLL and SEXE, can increase by 0x10 increments for each new revision
0xA	2	Padding
0xC	2	MetaData Offset
0xE	2	MetaData Size
0x10	4	Size of SELF
0x14	4	Padding
0x18	2	Number of Segments	1 SK, 2 SL and Modules, 4 SK Elfs, 6 .selfs, 2 .sdll, 6 .sprx, 6 ShellCore, 6 eboot.bin, 2 sexe
0x1A	2	Unknown	Always 0x22
0x1C	4	Padding

Self Segment Structure

Depending on the number of segments, at 0x20 the following structure follows and presents a size multiple of 0x20.

typedef struct
{
 unsigned short unknown_1; 
 unsigned short unknown_2;
 unsigned int padding;
 unsigned long long offset;
 unsigned long long encrypted_compressed_size
 unsigned long long decrypted_decompressed_size ;
} SEGMENT_TABLE;

ELF Segment Structure

After this, follows the ELF Header:

ELF header

Offset		Size (bytes)		Field	Purpose
32-bit	64-bit	32-bit	64-bit
0x00		4		e_ident[EI_MAG0] through e_ident[EI_MAG3]	0x7F followed by ELF(45 4c 46) in ASCII; these four bytes constitute the magic number.
0x04		1		e_ident[EI_CLASS]	This byte is set to either 1 or 2 to signify 32- or 64-bit format, respectively.
0x05		1		e_ident[EI_DATA]	This byte is set to either 1 or 2 to signify little or big endianness, respectively. This affects interpretation of multi-byte fields starting with offset 0x10.
0x06		1		e_ident[EI_VERSION]	Set to 1 for the original version of ELF.
0x07		1		e_ident[EI_OSABI]	Identifies the target operating system ABI. Value ABI 0x00 System V 0x01 HP-UX 0x02 NetBSD 0x03 Linux 0x04 GNU Hurd 0x06 Solaris 0x07 AIX 0x08 IRIX 0x09 FreeBSD 0x0A Tru64 0x0B Novell Modesto 0x0C OpenBSD 0x0D OpenVMS 0x0E NonStop Kernel 0x0F AROS 0x10 Fenix OS 0x11 CloudABI It is often set to 0 regardless of the target platform.
0x08		1		e_ident[EI_ABIVERSION]	Further specifies the ABI version. Its interpretation depends on the target ABI. Linux kernel (after at least 2.6) has no definition of it. In that case, offset and size of EI_PAD are 8.
0x09		7		e_ident[EI_PAD]	currently unused
0x10		2		e_type	Identifies object file type. Value Type 0x00 ET_NONE 0x01 ET_REL 0x02 ET_EXEC 0x03 ET_DYN 0x04 ET_CORE 0xfe00 ET_LOOS 0xfeff ET_HIOS 0xff00 ET_LOPROC 0xffff ET_HIPROC
0x12		2		e_machine	Specifies target instruction set architecture. Some examples are: Value ISA 0x00 No specific instruction set 0x02 SPARC 0x03 x86 0x08 MIPS 0x14 PowerPC 0x16 S390 0x28 ARM 0x2A SuperH 0x32 IA-64 0x3E x86-64 0xB7 AArch64 0xF3 RISC-V
0x14		4		e_version	Set to 1 for the original version of ELF.
0x18		4	8	e_entry	This is the memory address of the entry point from where the process starts executing. This field is either 32 or 64 bits long depending on the format defined earlier.
0x1C	0x20	4	8	e_phoff	Points to the start of the program header table. It usually follows the file header immediately, making the offset 0x34 or 0x40 for 32- and 64-bit ELF executables, respectively.
0x20	0x28	4	8	e_shoff	Points to the start of the section header table.
0x24	0x30	4		e_flags	Interpretation of this field depends on the target architecture.
0x28	0x34	2		e_ehsize	Contains the size of this header, normally 64 Bytes for 64-bit and 52 Bytes for 32-bit format.
0x2A	0x36	2		e_phentsize	Contains the size of a program header table entry.
0x2C	0x38	2		e_phnum	Contains the number of entries in the program header table.
0x2E	0x3A	2		e_shentsize	Contains the size of a section header table entry.
0x30	0x3C	2		e_shnum	Contains the number of entries in the section header table.
0x32	0x3E	2		e_shstrndx	Contains index of the section header table entry that contains the section names.

Followed by the program header

Program header

Offset		Size (bytes)		Field	Purpose
32-bit	64-bit	32-bit	64-bit
0x00		4		p_type	Identifies the type of the segment. Value Name Meaning 0x00000000 PT_NULL Program header table entry unused 0x00000001 PT_LOAD Loadable segment 0x00000002 PT_DYNAMIC Dynamic linking information 0x00000003 PT_INTERP Interpreter information 0x00000004 PT_NOTE Auxiliary information 0x00000005 PT_SHLIB reserved 0x00000006 PT_PHDR segment containing program header table itself 0x60000000 PT_LOOS see below 0x6FFFFFFF PT_HIOS 0x70000000 PT_LOPROC 0x7FFFFFFF PT_HIPROC PT_LOOS to PT_HIOS (PT_LOPROC to PT_HIPROC) is an inclusive reserved ranges for operating system (processor) specific semantics.
	0x04		4	p_flags	Segment-dependent flags (position for 64-bit structure).
0x04	0x08	4	8	p_offset	Offset of the segment in the file image.
0x08	0x10	4	8	p_vaddr	Virtual address of the segment in memory.
0x0C	0x18	4	8	p_paddr	On systems where physical address is relevant, reserved for segment's physical address.
0x10	0x20	4	8	p_filesz	Size in bytes of the segment in the file image. May be 0.
0x14	0x28	4	8	p_memsz	Size in bytes of the segment in memory. May be 0.
0x18		4		p_flags	Segment-dependent flags (position for 32-bit structure).
0x1C	0x30	4	8	p_align	0 and 1 specify no alignment. Otherwise should be a positive, integral power of 2, with p_vaddr equating p_offset modulus p_align.
0x20	0x38				End of Program Header (size)

SCE Special

Just before the start of the metadata a special section exists which contains the following:

Offset	Size	Description	Notes
0	0x8	AuthID
0x8	0x8	KeyType/VendorID?	0xC SK, 0xF SL, 0xE SM, 0x8 EBOOT and ELF and SELF, 0x9 SPRX and SDLL and SEXE
0x10	0x8	Version_1
0x18	0x8	Version_2
N.A/0x20	0x20	Content ID	Only exists if the self is NPDRM
0x20/0x40	0x20	SHA256SUM

Footer Signature (Extra)

Additionally, at the bottom, there is likely a footer signature as well as some extra data (size 0x4D bytes)