Certified File

Certified Files are the most common encrypted files on PS3 and PSVita.

Introduction

Not only ELF/PRX files can be signed with this format, other known Certified Files are:

• revoke list
• PS3 security policy profile
• system software package (e.g. .pkg, .spkg_hdr.X)
• PSVita diff file (never met such a file yet)
• PSVita game cartridge param.sfo (gro0:gc/param.sfo)

Structure

It is important to notice that PS3 uses big-endian whilst PSVita uses little-endian.

Header

typedef struct { // Size is 0x20 for v2, 0x30 for v3
  uint32_t magic;
  uint32_t version;
  uint16_t attribute;
  uint16_t category;
  uint32_t ext_header_size;
  uint64_t file_offset;
  uint64_t file_size;
  union {
    struct {
      uint64_t cf_file_size;
      uint64_t padding;
    };
  };
} __attribute__((packed)) cf_header;

field	offset	type	notes
Magic	0x0	u32	Must be "SCE\0".
Version	0x4	u32	2 for PS3, 3 for PSVita.
Attribute	0x8	u16	Corresponds to the revision of the enc/dec key. See Attribute.
Category	0xA	u16	See Category.
Extended Header size	0xC	u32	For SELF category only, set to 0 for other categories. See Extended Header.
File offset	0x10	u64	Offset to encapsulated data.
File size	0x18	u64	Size of the encapsulated data.
CF file size	0x20	u64	Size of the CF file. Present on version 3 only.
Padding	0x28	u64	Padding. Set to 0. Present on version 3 only.

Category

Value	Type	Name	Remark
1	SELF - SPRX	signed-elf - signed-prx	Used for storing ELF and PRX. Both PS3 and PSVita.
2	SRVK	signed-revoke-list	Used for Revokation. Both PS3 and PSVita.
3	SPKG	signed-package	Used for System Software Packages. Both PS3 and PSVita.
4	SSPP	signed-security-policy-profile	The only file of this category is Default.spp. PS3 only.
5	SDIFF	signed-diff	Used in Prototype PSVita Applier module. PSVita only. Never met such a file yet.
6	SPSFO	signed-param-sfo	Spsfo (signed param.sfo) file is located in game cartridge at path gro0:gc/param.sfo. PSVita only.

Encryption Root Header

Temp name was Metadata Information. Official name is encryption_root_header.

This is not present in fCF (fSELF, fSPP, etc...).

The key and iv fields are encrypted using AES256CBC.

Struct

typedef struct {
  uint8_t key[16];
  uint8_t key_pad[16];
  uint8_t iv[16];
  uint8_t iv_pad[16];
} __attribute__((packed)) encryption_root_header;

Certification Header

Temp name was Metadata Header. Official name is certification_header.

It is only present if the Encryption Root Header is present.

It is decrypted using AES128 with the key and iv entries from the Encryption Root Header.

It is located after the Encryption Root Header in the SELF file.

Struct

typedef struct {
  uint64_t sign_offset;             
  uint32_t sign_algorithm;            // 1 = ECDSA160, 2 = HMACSHA1, 3 = SHA1, 5 = RSA2048
  uint32_t cert_entry_number;
  uint32_t attr_entry_num;              
  uint32_t optional_header_size;
  uint64_t pad;
} __attribute__((packed)) certification_header;

Certification Body

• It is decrypted with the key and iv entries from the Encryption Root Header.

Segment Certification Header

Temp name was Metadata Section Header. Official name is segment_certification_header.

It is only present if the Certification Header is present.

The number of sections is indicated by the segment_count entry in the Certification Header.

The Segment Certification Header is located after the Certification Header in the SELF file.

Struct

typedef struct {
  uint64_t segment_offset;
  uint64_t segment_size;
  uint32_t segment_type;      // 1 = shdr, 2 = phdr, 3 = sceversion
  uint32_t segment_id;       // 0,1,2,3,etc for phdr, always 3 for shdrs, sceversion shdr number for sceversion
  uint32_t sign_algorithm;    // ?1 = none?, 2 = sha1_hmac, 3 = sha1, 6 = sha256_hmac
  uint32_t sign_idx;
  uint32_t decrypt_algorithm; // 1 = none, 2 = aes128cbccfb, 3 = aes128ctr
  uint32_t decrypt_idx;       // -1 when decrypt_algorithm = none
  uint32_t iv_idx;            // -1 when decrypt_algorithm = none
  uint32_t comp_algorithm;    // 1 = plain, 2 = zlib
} __attribute__((packed)) segment_certification_header;

Comments

Notes:

• Segment data is decrypted using decrypt_algorithm with the key and iv from the Segment Certification specified by key_idx and iv_idx.
• The segment_offset of the Segment Certification Header matches in general the offset from the Segment Extended Header.

Segment Certification

Temp name was Metadata Keys, Section Hash. Official name is attribute(s), found sub get_attribute(unsigned char *, unsigned int) on spp_verifier which returns pointer to signature/key/iv by it's id.

The number of Segment Certifications is indicated by the segment_count entry in the Certification Header.

The Segment Certifications are located after the Segment Certification Headers in the SELF file.

Struct

 typedef struct {
  union { // size is 0x60 bytes
    uint8_t signature[0x20]; // hmac_sha1
    uint8_t sign_key[0x40]; // certainly hmac_key
  } signature_type2;
  union { // size is 0x20 bytes
    uint8_t signature[0x20]; // sha1_hash
  } signature_type3;
  union { // size is 0x40 bytes
    uint8_t signature[0x20]; // hmac_sha256
    uint8_t hmac_key[0x20];
  } signature_type6;
  union { // size is 0x20 bytes
    uint8_t key[0x10];
    uint8_t iv[0x10];
  } encryption_params; // present for type 2 and 3
 } __attribute__((packed)) segment_certification;

Comments

Notes:

• The HMAC-SHA1 is calculated on the decrypted data and before the decompression.

Optional Header Table

Temp name was Signature Info, Capabilities Info. Official name is optional_header_table.

The Optional Header Table is located after the Section Hash in the SELF file.

It is only present if optional_header_size in the Certification Header is not zero.

Struct

typedef struct {
	uint32_t type; // 1=capability_header, 2=individual_seed_header, 3=attribute_header
	uint32_t size;
	uint64_t next; // 1 if another optional_header structure follows else 0
	union {
		// type 1
		struct { // 0x20 bytes of data
			uint8_t capability[0x20];
		} capability_header;
		// type 2
		struct { // 0x100 bytes of data
			uint8_t individual_seed[0x100];
		} individual_seed_header;
		// type 3
		struct { // 0x20 bytes of data
			uint8_t attribute[0x20];
		} attribute_header;
	};
} __attribute__((packed)) optional_header;

Comments

• Type 1 contains encrypted_capability. See Capability Flags.

Certification Footer

Temp name was Signature.

It is located at the Certification Header footer_offset in the SELF file.

It is decrypted with the key and iv entries from the Encryption Root Header.

It can be ECDSA160 or RSA2048, according to the Certification Header.

Struct

typedef struct {
  union {
    uint8_t r[21];
    uint8_t s[21];
    uint8_t padding[6];
  } ECDSA160;
  union {
    uint8_t rsa[0x100];
  } RSA2048;
} __attribute__((packed)) certification_footer;

Comments

• footer_offset is the number of bytes which are used to generate the SHA-1 which is used to generate the ECDSA signature. The length should be eveything from the beginning until the signature itself. The decrypted version of the input data is used for signature.

Decryption

Certified Files are all encrypted using the exact same algorithm (except for Fake Certified Files). They can be encrypted, hashed and signed. This section only focuses on the encryption layer.

• Step 0: Get Encryption Root Header Master Keys

On PS3, TO DOCUMENT.

On PSVita, static key and IV are contained within the relevant Secure Module. For example, SPKG keys are located in update_service_sm.self, KPRX keys are located in kprx_auth_sm.self, Secure Modules (SM) as well as kernel_boot_loader.self keys are located in secure_kernel.

• Step 1: Get Encryption Root key and IV

Decrypt the Certification Header using AES256CBC on PSVita (to document for PS3).

This results into the key and IV used in step 2.

• Step 2: Get plain Certification

Use the key and IV decrypted from the Encryption Root Header to decrypt the Certification using AES128CBC on PSVita (what on PS3 ?).

• Step 3: Parse Certification

The SELF Certification is typically stored in the following format (below is a CF metadata example of a 4 sections PSVita SELF).

The SPKG Certification follows the same principles but is slightly different (different Magic/Header).

Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00000000  F0 07 00 00 00 00 00 00 05 00 00 00 04 00 00 00  ð...............  <<< Certification Header
00000010  18 00 00 00 70 01 00 00 00 00 00 00 00 00 00 00  ....p...........  <<< Certification Header
00000020  00 0A 00 00 00 00 00 00 C0 00 00 00 00 00 00 00  ........À.......  <<< First section address
00000030  02 00 00 00 01 00 00 00 06 00 00 00 00 00 00 00  ................
00000040  03 00 00 00 04 00 00 00 05 00 00 00 01 00 00 00  ................
00000050  00 0B 00 00 00 00 00 00 FC B4 07 00 00 00 00 00  ........ü´......  <<< Second section address
00000060  02 00 00 00 02 00 00 00 06 00 00 00 06 00 00 00  ................
00000070  03 00 00 00 0A 00 00 00 0B 00 00 00 01 00 00 00  ................
00000080  00 C0 07 00 00 00 00 00 98 1E 00 00 00 00 00 00  .À......˜.......  <<< Third section address
00000090  02 00 00 00 03 00 00 00 06 00 00 00 0C 00 00 00  ................
000000A0  03 00 00 00 10 00 00 00 11 00 00 00 01 00 00 00  ................
000000B0  00 DF 07 00 00 00 00 00 9D BA 02 00 00 00 00 00  .ß.......º......  <<< Fourth section address
000000C0  02 00 00 00 04 00 00 00 06 00 00 00 12 00 00 00  ................
000000D0  03 00 00 00 16 00 00 00 17 00 00 00 01 00 00 00  ................
000000E0  AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA  ªªªªªªªªªªªªªªªª  <<< First Section Hash
000000F0  AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA  ªªªªªªªªªªªªªªªª  <<< First Section Hash
00000100  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ
00000110  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ
00000120  EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE  îîîîîîîîîîîîîîîî  <<< First Section random key
00000130  EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE  îîîîîîîîîîîîîîîî  <<< First Section random IV
00000140  BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB  »»»»»»»»»»»»»»»»  <<< Second Section Hash
00000150  BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB  »»»»»»»»»»»»»»»»  <<< Second Section Hash
00000160  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ  <<< HMAC key
00000170  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ  <<< HMAC key
00000180  EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE  îîîîîîîîîîîîîîîî  <<< Second Section random key
00000190  EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE  îîîîîîîîîîîîîîîî  <<< Second Section random IV
000001A0  CC CC CC CC CC CC CC CC CC CC CC CC CC CC CC CC  ÌÌÌÌÌÌÌÌÌÌÌÌÌÌÌÌ  <<< Third Section Hash
000001B0  CC CC CC CC CC CC CC CC CC CC CC CC CC CC CC CC  ÌÌÌÌÌÌÌÌÌÌÌÌÌÌÌÌ  <<< Third Section Hash
000001C0  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ  <<< HMAC key
000001D0  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ  <<< HMAC key
000001E0  EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE  îîîîîîîîîîîîîîîî  <<< Third Section random key
000001F0  EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE  îîîîîîîîîîîîîîîî  <<< Third Section random IV
00000200  DD DD DD DD DD DD DD DD DD DD DD DD DD DD DD DD  ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ  <<< Fourth Section Hash
00000210  DD DD DD DD DD DD DD DD DD DD DD DD DD DD DD DD  ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ  <<< Fourth Section Hash
00000220  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ  <<< HMAC key
00000230  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ  <<< HMAC key
00000240  EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE  îîîîîîîîîîîîîîîî  <<< Fourth Section random key
00000250  EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE EE  îîîîîîîîîîîîîîîî  <<< Fourth Section random IV
00000260  01 00 00 00 30 00 00 00 01 00 00 00 00 00 00 00  ....0...........  <<< type (u32), section size (u32), isMoreSections (u32)
00000270  80 00 00 00 C0 00 F0 00 00 00 00 00 FF FF FF FF  €...À.ð.....ÿÿÿÿ 
00000270  80 00 00 00 C0 00 F0 00 00 00 00 00 FF FF FF FF  €...À.ð.....ÿÿÿÿ
00000280  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000290  02 00 00 00 10 01 00 00 01 00 00 00 00 00 00 00  ................  <<< type (u32), section size (u32), isMoreSections (u32)
000002A0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000002B0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000002C0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000002D0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000002E0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000002F0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000300  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000310  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000320  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000330  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000340  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000350  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000360  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000370  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000380  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000390  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000003A0  03 00 00 00 30 00 00 00 00 00 00 00 00 00 00 00  ....0...........  <<< type (u32), section size (u32), isMoreSections (u32)
000003B0  80 09 80 03 00 00 C3 00 00 00 80 09 80 00 00 00  €.€...Ã...€.€...
000003C0  00 00 00 00 00 00 00 00 00 00 00 00 FF FF FF FF  ............ÿÿÿÿ
000003D0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000003E0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000003F0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000400  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000410  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000420  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000430  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000440  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000450  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000460  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000470  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000480  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000490  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000004A0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000004B0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000004C0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000004D0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................  <<< Certification Body end, padding

Following the same principles, a plain SPKG Certification Body looks like this:

Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00000000  00 02 00 00 00 00 00 00 05 00 00 00 03 00 00 00  ................ <<< Certification Header
00000010  0E 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................ <<< Certification Header
00000020  00 03 00 00 00 00 00 00 40 00 00 00 00 00 00 00  ........@.......
00000030  01 00 00 00 01 00 00 00 06 00 00 00 00 00 00 00  ................
00000040  01 00 00 00 FF FF FF FF FF FF FF FF 01 00 00 00  ....ÿÿÿÿÿÿÿÿ....
00000050  40 03 00 00 00 00 00 00 40 00 00 00 00 00 00 00  @.......@.......
00000060  02 00 00 00 02 00 00 00 06 00 00 00 04 00 00 00  ................
00000070  01 00 00 00 FF FF FF FF FF FF FF FF 01 00 00 00  ....ÿÿÿÿÿÿÿÿ....
00000080  80 03 00 00 00 00 00 00 00 00 80 00 00 00 00 00  €.........€.....
00000090  03 00 00 00 03 00 00 00 06 00 00 00 08 00 00 00  ................
000000A0  03 00 00 00 0C 00 00 00 0D 00 00 00 01 00 00 00  ................
000000B0  AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA  ªªªªªªªªªªªªªªªª  <<< Hash
000000C0  AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA  ªªªªªªªªªªªªªªªª  <<< Hash
000000D0  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ
000000E0  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ
000000F0  BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB  »»»»»»»»»»»»»»»»  <<< Hash
00000100  BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB  »»»»»»»»»»»»»»»»  <<< Hash
00000110  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ
00000120  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ
00000130  CC CC CC CC CC CC CC CC CC CC CC CC CC CC CC CC  ÌÌÌÌÌÌÌÌÌÌÌÌÌÌÌÌ  <<< Hash
00000140  CC CC CC CC CC CC CC CC CC CC CC CC CC CC CC CC  ÌÌÌÌÌÌÌÌÌÌÌÌÌÌÌÌ  <<< Hash
00000150  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ  <<< Random key
00000160  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ  <<< Random IV
00000170  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ  <<< Random key
00000180  FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF  ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ  <<< Random IV
00000190  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000001A0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000001B0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000001C0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000001D0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000001E0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
000001F0  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000200  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000210  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000220  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000230  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000240  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000250  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000260  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG
00000270  11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11  ................  <<< RSA SIG

• Step 4: Get plain CF sections

Use the keys and IVs with the specified algorithm from the Segment Certification to decrypt the respective sections.

• Step 5: Uncompress CF sections if needed

CF sections can be compressed. This is reported in the Segment Certification Header.