SELF File Format: Difference between revisions
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|- | |- | ||
| 0x20/0x40 || 0x20 || Digest || SHA-256 of the decrypted elf (for example, on 7.55 retail decrypted/mmapped elf libc.sprx hash is 67c19a2b053ee386819dcd316d21c4381b35bd3de283ce7ca2e143c86b34f79a) | | 0x20/0x40 || 0x20 || Digest || SHA-256 of the decrypted elf (for example, on 7.55 retail decrypted/mmapped elf libc.sprx hash is 67c19a2b053ee386819dcd316d21c4381b35bd3de283ce7ca2e143c86b34f79a) | ||
|} | |||
= Metadata = | |||
From leaked 6.00b1 Kernel (containing only one segment) the following information can be deduced: | |||
{| class="wikitable" | |||
! Offset !! Size !! Description !! Notes | |||
|- | |||
| 0 || 0x10 || AES Key || CBC 128 Key for Segment 1 | |||
|- | |||
| 0x10 || 0x10 || AES IV || CBC 128 IV for Segment 1 | |||
|- | |||
| 0x20 || 0x20 || SHA256HMAC || SHA256HMAC for Segment 1 (Decrypted But Compressed in this case) (Without Extra at Footer) | |||
|- | |||
| 0x40 || 0x10 || HMAC Key || SHA256HMAC Key for Segment 1 | |||
|- | |||
| 0x50 || 0x40 || License + BMP Header || ??? | |||
|- | |||
| 0x90 || 0x20 || BMP Entries || 2 (0x10) Entries (First entry is NULL) | |||
|- | |||
| 0xB0 || 0x100 || RSA SIG || RSA Signature that validates Header Meta | |||
|- | |||
|} | |} | ||
Revision as of 21:57, 18 July 2021
ORBIS SELFs (and PUP entries) have a different structure from the PS3 and PSVita ones.
SELF Header Structure
Offset | Size | Description | Notes |
---|---|---|---|
0 | 4 | Magic | 4F 15 3D 1D |
0x4 | 4 | Unknown | Always 00 01 01 12 |
0x8 | 1 | Content Type | 1 on Self, 4 on PUP Entry |
0x9 | 1 | Program Type | |
0xA | 2 | Padding | |
0xC | 2 | Header Size | |
0xE | 2 | Signature Size | Metadata Size? |
0x10 | 4 | Size of SELF | |
0x14 | 4 | Padding | |
0x18 | 2 | Number of Segments | 1 Kernel, 2 SL and Modules, 4 Kernel 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 long long flags; // 0x130006 / 0x00040F / 0x000006 / 0x110006 unsigned long long offset; unsigned long long encrypted_compressed_size; unsigned long long decrypted_decompressed_size; } SEGMENT_TABLE;
Flags ID
enum SegFlags { SF_ORDR = 0x1, // ordered? SF_ENCR = 0x2, // encrypted SF_SIGN = 0x4, // signed SF_DFLG = 0x8, // deflated SF_BFLG = 0x800, // block segment };
Flags Maths
uint32_t Id() { return Flags >> 20; //0 or 1 } bool IsOrdered() { return (Flags & 1) != 0;//0 or 1 } bool IsEncrypted() { return (Flags & 2) != 0;//0 or 2 } bool IsSigned() { return (Flags & 4) != 0;//0 or 4 } bool IsCompressed() { return (Flags & 8) != 0;//0 or 8 } bool IsBlocked() { return (Flags & 0x800) != 0;//0 or 0x800 }
ELF Segment Structure
After this, follows the 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 ( ) 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.
It is often set to | ||||||||||||||||||||||||||||||||||||||
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.
| ||||||||||||||||||||||||||||||||||||||
0x12 | 2 | e_machine | Specifies target instruction set architecture. Some examples are:
| ||||||||||||||||||||||||||||||||||||||
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
Offset | Size (bytes) | Field | Purpose | |||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
32-bit | 64-bit | 32-bit | 64-bit | |||||||||||||||||||||||||||||||||||
0x00 | 4 | p_type | Identifies the type of the segment.
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 | Program Authority ID | |
0x8 | 0x8 | Program Type | |
0x10 | 0x8 | Version 1 | |
0x18 | 0x8 | Version 2 | |
N.A/0x20 | 0x20 | Content ID | Only exists if the SELF is NPDRM |
0x20/0x40 | 0x20 | Digest | SHA-256 of the decrypted elf (for example, on 7.55 retail decrypted/mmapped elf libc.sprx hash is 67c19a2b053ee386819dcd316d21c4381b35bd3de283ce7ca2e143c86b34f79a) |
Metadata
From leaked 6.00b1 Kernel (containing only one segment) the following information can be deduced:
Offset | Size | Description | Notes |
---|---|---|---|
0 | 0x10 | AES Key | CBC 128 Key for Segment 1 |
0x10 | 0x10 | AES IV | CBC 128 IV for Segment 1 |
0x20 | 0x20 | SHA256HMAC | SHA256HMAC for Segment 1 (Decrypted But Compressed in this case) (Without Extra at Footer) |
0x40 | 0x10 | HMAC Key | SHA256HMAC Key for Segment 1 |
0x50 | 0x40 | License + BMP Header | ??? |
0x90 | 0x20 | BMP Entries | 2 (0x10) Entries (First entry is NULL) |
0xB0 | 0x100 | RSA SIG | RSA Signature that validates Header Meta |
Additionally, at the bottom, there is likely a footer signature as well as some extra data (relative size).