/dev/crypto

/dev/crypto is the IOSU device node for the cryptographic engine. It can only be opened by the IOSU and it also provides a stripped down library (IOSC) that is implemented on most IOSU modules under the name "crypto_ios_interface". Requests are issued via ioctl()/ioctlv() commands which are then mapped to internal functions inside the IOS-CRYPTO process. This is done using different message queues, each one mapping a subset of commands in a jump table:

0x00: Mapped by the 3rd message queue
0x01: Mapped by the 3rd message queue
0x02: Mapped by the 4th message queue
0x03: Mapped by the 4th message queue
0x04: Mapped by the 4th message queue
0x05: Mapped by the 4th message queue
0x06: Mapped by the 3rd message queue
0x07: Mapped by the 4th message queue
0x08: Mapped by the 4th message queue
0x09: Mapped by the 3rd message queue
0x0A: Mapped by the 3rd message queue
0x0B: Mapped by the 2nd message queue | Mapped by the 4th message queue (async version)
0x0C: Mapped by the 2nd message queue
0x0D: Mapped by the 2nd message queue
0x0E: Mapped by the 4th message queue
0x0F: Mapped by the 2nd message queue | Mapped by the 4th message queue (async version)
0x10: Mapped by the 4th message queue
0x11: Mapped by the 3rd message queue
0x12: Mapped by the 4th message queue
0x13: Mapped by the 4th message queue
0x14: Mapped by the 1st message queue
0x15: Mapped by the 3rd message queue
0x16: Mapped by the 4th message queue
0x17: Mapped by the 4th message queue
0x18: Not mapped
0x19: Mapped by the 2nd message queue
0x1A: Mapped by the 2nd message queue
0x1B: Mapped by the 1st message queue
0x1C: Mapped by the 2nd message queue
0x1D: Mapped by the 1st message queue
0x1E: Mapped by the 1st message queue
0x1F: Mapped by the 4th message queue
0x20: Mapped by the 4th message queue
0x21: Mapped by the 1st message queue
0x22: Mapped by the 3rd message queue

List of functions (ioctl/ioctlv)

Command	Function	Call	Description	Notes
0x01	IOSC_CreateObject()	IOS_Ioctl(FD, 0x01, in_buf, 0x10, out_buf, 4);	Creates a new crypto object and returns a handle for it.
0x02	IOSC_DeleteObject()	IOS_Ioctl(FD, 0x02, in_buf, 4, 0, 0);	Deletes a crypto object.
0x03	IOSC_ImportSecretKey()	IOS_Ioctlv(FD, 0x03, 4, 0, vector);
0x04	keyring_deallocate_entry()	IOS_Ioctlv(FD, 0x04, 1, 3, vector);
0x05	import_pub_key()	IOS_Ioctlv(FD, 0x05, 3, 0, vector);
0x06	export_root()	IOS_Ioctlv(FD, 0x06, 1, 3, vector);
0x07	compute_shared_key()	IOS_Ioctl(FD, 0x07, in_buf, 0x10, 0, 0);
0x08	set_device_id()	IOS_Ioctlv(FD, 0x08, 2, 0, vector);
0x09	get_device_id()	IOS_Ioctlv(FD, 0x09, 1, 1, vector);
0x0A	get_key_size()	IOS_Ioctl(FD, 0x0A, in_buf, 4, out_buf, 4);
0x0B	get_key_userdata_size()	IOS_Ioctl(FD, 0x0B, in_buf, 4, out_buf, 4);
0x0C	IOSC_GenerateHash() / IOSC_GenerateHashAsync();	IOS_Ioctlv(FD, 0x0C, 3, 1, vector); / IOS_IoctlvAsync(FD, 0x0C, 3, 1, vector, queueid, message);		This function has 2 different implementations, one async and the other not.
0x0D	IOSC_Encrypt() / IOSC_EncryptAsync()	IOS_Ioctlv(FD, 0x0D, 3, 1, vector); / IOS_IoctlvAsync(FD, 0x0D, 3, 1, vector, queueid, message);		This function has 2 different implementations, one async and the other not.
0x0E	IOSC_Decrypt() / IOSC_DecryptAsync()	IOS_Ioctlv(FD, 0x0E, 3, 1, vector); / IOS_IoctlvAsync(FD, 0x0E, 3, 1, vector, queueid, message);		This function has 2 different implementations, one async and the other not.
0x0F	verify_public_key_sign()	IOS_Ioctlv(FD, 0x0F, 3, 0, vector);
0x10	IOSC_GenerateBlockMAC() / IOSC_GenerateBlockMACAsync()	IOS_Ioctlv(FD, 0x10, 4, 1, vector); / IOS_IoctlvAsync(FD, 0x10, 4, 1, vector, queueid, message);		This function has 2 different implementations, one async and the other not.
0x11	verify_cert()	IOS_Ioctlv(FD, 0x11, 2, 0, vector);
0x12	get_device_cert()	IOS_Ioctl(FD, 0x12, 0, 0, out_buf, 0x180);
0x13	set_title_key_ownership()	IOS_Ioctlv(FD, 0x13, 2, 0, vector);
0x14	get_title_key_ownership()	IOS_Ioctlv(FD, 0x14, 1, 1, vector);
0x15	IOSC_GenerateRand()	IOS_Ioctl(FD, 0x15, 0, 0, out_buf, out_size);	Generate random data of an arbitrary size.
0x16	generate_secret_key()	IOS_Ioctl(FD, 0x16, in_buf, 4, 0, 0);
0x17	sign()	IOS_Ioctlv(FD, 0x17, 2, 1, vector);
0x18	IOSC_GenerateCertificate()	IOS_Ioctlv(FD, 0x18, 2, 1, vector);
0x19	Unknown	IOS_Ioctl(FD, 0x19, ???, ???, ???, ???);		This command is not mapped by the IOS-CRYPTO process.
0x1A	odm_encrypt()	IOS_Ioctlv(FD, 0x1A, 3, 2, vector);
0x1B	odm_generate_session_key()	IOS_Ioctlv(FD, 0x1B, 3, 1, vector);
0x1C	get_security_level()	IOS_Ioctl(FD, 0x1C, 0, 0, out_buf, 4);	Gets the security level flag from the OTP.
0x1D	cryptoReadHashedBlock()	IOS_Ioctlv(FD, 0x1D, 5, 1, vector);
0x1E	read_wii_seeprom_data()	IOS_Ioctl(FD, 0x1E, 0, 0, out_buf, 0x60);	Reads the old Wii SEEPROM certificate data from OTP's bank 6.
0x1F	generate_wagonu_key()	IOS_Ioctl(FD, 0x1F, ???, ???, ???, ???);	Generates the WagonU key used to encrypt/decrypt data for Wii U to Wii U system transfers.
0x20	IOSC_EncryptBlocks()	IOS_Ioctlv(FD, 0x20, 3, 1, vector);	Software AES encryption, this supports multiple AES-modes(AES-CTR, ...). Used by IOS-PAD to encrypt amiibo data.
0x21	IOSC_DecryptBlocks()	IOS_Ioctlv(FD, 0x21, 3, 1, vector);	Software AES decryption version of the above ioctlv. Used by IOS-PAD to decrypt amiibo data.
0x22	mcp_auth_unk()	IOS_Ioctl(FD, 0x22, in_buf, 4, 0, 0);
0x23	mcp_wagon_archive_unk()	IOS_Ioctl(FD, 0x23, in_buf, 0x10, out_buf, 0x200);

Key object handles

The above crypto commands use key/crypto object handles. These handles can be either from IOSC_CreateObject(which can then be initialized with import_secret_key in the case of AES), or a built-in handle. The available built-in handles/keyids are listed below.

The maximum number of keyobject-handles is 0x80, hence the highest valid keyobject-handle is 0x7F. Keyobject-handles <=0x40 are reserved for built-in handles, the rest are available for user-processes. Commands which write keyobjects' keydata are only allowed to use handles with value >0x40(user-process handles).

ID	Type	Description
0x00	ECC-233	Unknown private key. Possibly vWii NG ECC key.
0x01	NONE	Unknown ID (0x04 bytes). Possibly vWii NG ID.
0x02	UNK	Unknown (0x10 bytes).
0x03	UNK	Unknown (0x14 bytes).
0x04	AES-128	Old Wii common key.
0x05	UNK	Unknown (0x10 bytes).
0x06	AES-128	Fixed key stored in IOS-CRYPTO's data.
0x07	AES-128	Wii U SEEPROM key.
0x08	NONE	Unused.
0x09	NONE	Unused.
0x0A	NONE	Unused.
0x0B	UNK	Unknown (0x10 bytes).
0x0C	UNK	Unknown (0x10 bytes).
0x0D	AES-128	ARM Ancast Image (this and the below one are for all ARM-ancast images launched via IOS-MCP).
0x0E	RSA-2048 modulus	ARM Ancast Image (stored inside IOS-CRYPTO's data).
0x0F	RSA-2048 modulus	Unknown (stored inside IOS-CRYPTO's data).
0x10	AES-128	Wii U common key.
0x11	UNK	Unknown (0x10 bytes).
0x12	AES-128	WagonU key.
0x13	AES-128	Old Wii NAND key.
0x14	HMAC SHA-1	Old Wii NAND HMAC.
0x15	AES-128	vWii common key.
0x16	UNK	Unknown (0x10 bytes).
0x17	UNK	Unknown (0x10 bytes).
0x18	UNK	Unknown (0x10 bytes).
0x19	UNK	Unknown (0x10 bytes).
0x1A	UNK	Unknown (0x10 bytes).
0x1B	AES-128	Key to encrypt/decrypt SSL RSA key.
0x1C	UNK	Unknown (0x1E bytes).
0x1D	UNK	Unknown (0x1E bytes).
0x1E	UNK	Unknown (0x10 bytes).
0x1F	UNK	Unknown (0x10 bytes).
0x20	UNK	Unknown (0x40 bytes).
0x21	UNK	Unknown (0x40 bytes).
0x22	UNK	Unknown (0x40 bytes).
0x23	UNK	Unknown (0x40 bytes).
0x24	UNK	Unknown (0x10 bytes).
0x25	UNK	Unknown (0x10 bytes).
0x26	UNK	Unknown (0x10 bytes).
0x27	UNK	Unknown (0x10 bytes).
0x28	UNK	Unknown (0x10 bytes).
0x29 to 0x40	UNK	Unused.