Title metadata

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Nintendo Wii Title-Metadata (tmd) file structure

A "title" is a standalone entity -- a game, a channel, etc. Titles can be made up of multiple "contents". (Don't ask me. I just work here.)

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.

typedef unsigned char  u8;
typedef unsigned short u16;
typedef unsigned int   u32; 
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: 0x30 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[...];