In memory of Ben “bushing” Byer, who passed away on Monday, February 8th, 2016.

Title metadata

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Title metadata is a format used to store information about a title (a single standalone game, channel, etc.) and all its installed contents, including which contents they consist of and their SHA1 hashes.

Many operations are done in terms of 64-byte blocks, which means you will often see padding out to the nearest 64-byte boundary at the end of a field.

Structure

Header

Start Length Description
0x000 4 Signature type
0x004 256 Signature
0x104 60 Padding modulo 64
0x140 64 Issuer
0x180 1 Version
0x181 1 ca_crl_version
0x182 1 signer_crl_version
0x183 1 Padding modulo 64
0x184 8 System Version (the ios that the title need)
0x18C 8 Title ID
0x194 4 Title type
0x198 2 Group ID
0x19A 62 reserved
0x1D8 4 Access rights
0x1DC 2 Title version
0x1DE 2 Number of contents (nbr_cont)
0x1E0 2 boot index
0x1E2 2 Padding modulo 64
0x1E4 36*nbr_cont Contents

Content

Start Length Description
0x00 4 Content ID
0x04 2 Index
0x06 2 Type
0x08 8 Size
0x10 20 SHA1 hash

Certificates

Start Length Description
0x000 4 Signature type
0x004 256 Signature
0x104 32 Issuer
0x124 4 Tag
0x128 64 Name
0x168 Key

Example code application

 typedef unsigned char  u8;
 typedef unsigned short u16;
 typedef unsigned int   u32; 
/* On a 32bit system, long is only 4 bytes- use long long instead */
 typedef unsigned long u64;
 typedef struct {
   u32 cid;		// content id
   u16 index;		// # number of the file
   u16  type;
   u64 size;
   u8  hash [20]; 		//  SHA1 hash content
 } content_record; 			// size: 0x24 bytes
 enum sig_type {
      RSA_2048 = 0x00010001,
      RSA_4096 = 0x00010000
 };
 typedef struct {
        u32 sig_type; 
        u8 sig[256];
        u8 fill1[60];
        u8 issuer[64]; // Root-CA%08x-CP%08x
        u8 version;
        u8 ca_crl_version;
        u8 signer_crl_version;
        u8 fill2;
        u64 sys_version;
        u64 title_id;
        u32 title_type;
        u16 group_id; // publisher
        u8 reserved[62];
        u32 access_rights;
        u16 title_version;
        u16 num_contents;
        u16 boot_index;
        u16 fill3;
        content_record contents[num_contents];
 } tmd;

The tmd is then followed by a chain of certificates, where each certificate is of the general form

  u32 sig_type;  //
  u8 sig[256];   // 256 for RSA_2048, 512 for RSA_4096
  u8 issuer[32];
  u32 tag;  // identifies what is being signed
  u8 name[64]; // name of thing being signed
  u8 key[...];

There is also a structure called a TmdView which is select sections of the Tmd. It has a length of 0x60+0x10*number_of_contents. The structure is somewhat like this [as returned by ES_GetTmdView] :

struct tmd_view_content_t
{
	uint32_t id;
	uint16_t index;
	uint16_t type;
	uint64_t size;
};

struct tmd_view_t
{
	uint8_t version; // 0x0000;
	uint8_t filler[3];
	uint64_t ios_title_id; //0x0004
	uint64_t title_id; // 0x00c
	uint32_t title_type; //0x0014
	uint16_t group_id; //0x0018
	uint8_t reserved[0x3e]; //0x001a this is the same reserved 0x3e bytes from the tmd
	uint16_t title_version; //0x0058
	uint16_t number_contents; //0x005a
	tmd_view_content_t contents[]; //0x005c
};