Title metadata

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.

TMD file 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
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

C 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[...];