SPL services

SPL ("Secure Platform services") is responsible for handling all cryptographic operations within the system and relaying them to the Secure Monitor when necessary.

During [1.0.0-3.0.2], the only existing services were "csrng" and "spl:". However, in [4.0.0+] the "spl:" service was refactored and split into new services with different permission levels. Each service exposes the IPC command list differently in order to prevent cryptographic operations to take place in the wrong context.

In [2.0.0+] where previously only one AES keyslot was used, there is now support for 4 of them and when the session closes, all allocated AES keyslots are automatically freed.

[S2] The spl services were overhauled. New services were added, this appears to replace spl:mig where required for the relevant sysmodules. GenerateAesKek is no longer directly exposed, thus the Kek AccessKey and KeySource are no longer exposed.

csrng

This is "nn::spl::detail::IRandomInterface".

Cmd	Name
0	#GenerateRandomBytes

GenerateRandomBytes

Takes an output type-0xA buffer and fills it with random data from GenerateRandomBytes SMC. Same command for "spl:" and "csrng" services, except for buffer-type.

spl:

This is "nn::spl::detail::IGeneralInterface".

Cmd	Name
0	#GetConfig
1	#ModularExponentiate
5	#SetConfig
7	#GenerateRandomBytes
11	#IsDevelopment
24	[3.0.0+] #SetBootReason
25	[3.0.0+] #GetBootReason

Going by spl:ldn, this likely has a new interface on [S2]:

Cmd	Name
0	GenerateRandomBytes
1	GetConfig
2
3
4
5	GetConfigWithBuffer

GetConfig

Wrapper for GetConfig SMC.

Takes an input u32 ConfigItem. Returns one or more output u64s ConfigValue.

ModularExponentiate

Wrapper for ModularExponentiate SMC.

Takes an output type-0xA buffer DataOut and 3 input type-0x9 buffers DataIn, ExpIn and ModIn.

Performs asymmetric crypto with user supplied modulus and exponent.

Cmd2

This is for the [S2] interface.

Takes no input, returns 0x10-bytes of output.

This returns the first 0xD-bytes from GetConfigWithBuffer ConfigItem 8, byteswapped.

Cmd3

This is for the [S2] interface.

Takes no input. Returns unknown output, usually zeros?

Cmd4

This is for the [S2] interface.

Takes no input. Returns unknown output, usually zeros?

GetConfigWithBuffer

Unofficial name.

Some config is incomplete when accessed with GetConfig, this allows returning the full config.

Takes an input u32 ConfigItem and an output type-0xA buffer.

GenerateAesKek

Wrapper for GenerateAesKek SMC.

Takes an input 16-byte KeySource and two input u32s Generation and Option. Returns an output 16-byte AccessKey.

LoadAesKey

Wrapper for LoadAesKey SMC.

Takes an input u32 KeySlot , an input 16-byte AccessKey and an input 16-byte KeySource.

Sets the specified KeySlot with a key generated from AccessKey and KeySource.

[2.0.0+] Now verifies that the keyslot in use (0..3) is allocated by the current spl session, otherwise errors with 0xD21A. Previously, keyslot was hardcoded to 0.

GenerateAesKey

Takes an input 16-byte AccessKey and an input 16-byte KeySource. Returns an output 16-byte AesKey.

Generates a new key by decrypting (AES-ECB) KeySource with a key generated from the supplied AccessKey and the key set with LoadAesKey SMC.

[2.0.0+] Previously, it always used keyslot 0. Now it tries to allocate a keyslot to be used and returns 0xD01A if they're all busy. When the command is done, the keyslot is released.

SetConfig

Wrapper for SetConfig SMC.

Takes an input u32 ConfigItem and an input u64 ConfigValue.

Only ConfigItem 13 (IsChargerHiZModeEnabled) can be set.

DecryptAndStoreGcKey

Wrapper for DecryptAndImportLotusKey SMC.

Takes an input type-0x9 buffer DataIn, an input 16-byte AccessKey, an input 16-byte KeySource and an input u32 Version (0 for normal keys or 1 for extended keys).

Decrypts DataIn with a key generated from AccessKey and KeySource and imports it for later usage.

[5.0.0+] The Version argument was removed and this now calls the ReencryptDeviceUniqueData SMC instead.

DecryptGcMessage

Takes 3 input type-0x9 buffers DataIn, ModIn and LabelHashIn.

Uses the ModularExponentiateByStorageKey SMC to decrypt DataIn using the private key imported with #DecryptAndStoreGcKey and the supplied ModIn and LabelHashIn.

IsDevelopment

No input. Returns an output u8 bool.

Uses #GetConfig internally.

GenerateSpecificAesKey

Wrapper for GenerateSpecificAesKey SMC.

Takes an input 16-byte KeySource and two input u32s Generation and Option. Returns an output 16-byte AesKey.

DecryptDeviceUniqueData

Wrapper for DecryptDeviceUniqueData SMC.

Takes an output type-0xA buffer DataOut, an input type-0x9 DataIn, an input 16-byte AccessKey, an input 16-byte KeySource and an input u32 Version (0 for normal keys or 1 for extended keys).

Decrypts DataIn into DataOut with a key generated from AccessKey and KeySource.

Used by SSL for TLS client-privk.

[5.0.0+] The Version argument was removed.

DecryptAesKey

Takes an input 16-byte KeySource and two input u32s Generation and Option. Returns an output 16-byte AesKey.

Decrypts (AES-ECB) KeySource with a key set with LoadAesKey SMC.

[2.0.0+] Introduced same keyslot allocation code as for #GenerateAesKey.

ComputeCtr

Takes an output type-0x46 buffer DataOut, an input u32 KeySlot, an input type-0x45 buffer DataIn and an input 16-byte IvCtr.

Uses ComputeAes SMC to decrypt DataIn into DataOut using the key set in the specified KeySlot.

[2.0.0+] Verifies the keyslot was allocated by the current session.

ComputeCmac

Wrapper for ComputeCmac SMC.

Takes an input type-0x9 buffer DataIn and an input u32 KeySlot. Returns an output 16-byte Cmac.

[2.0.0+] Verifies the keyslot was allocated by the current session.

LoadEsDeviceKey

Wrapper for DecryptAndImportEsDeviceKey SMC.

Takes an input type-0x9 buffer DataIn, an input 16-byte AccessKey, an input 16-byte KeySource and an input u32 Version (0 for normal keys or 1 for extended keys).

Decrypts DataIn with a key generated from AccessKey and KeySource and imports it for later usage.

[5.0.0+] The Version argument was removed and this now calls the ReencryptDeviceUniqueData SMC instead.

PrepareEsTitleKey

Wrapper for PrepareEsDeviceUniqueKey SMC.

Takes an output type-0xA buffer DataOut and 3 input type-0x9 buffers DataIn, ModIn and LabelHashIn. Returns an output u32 DataOutSize.

[3.0.0+] Now takes an input u32 Generation.

Decrypts DataIn into DataOut using the private key imported with #LoadEsDeviceKey and the supplied ModIn. Afterwards, verifies RSA-OAEP encoding using LabelHashIn.

LoadPreparedAesKey

Wrapper for LoadPreparedAesKey SMC.

Takes an input u32 KeySlot and an input 16-byte AccessKey.

[2.0.0+] Verifies the keyslot was allocated in the current session.

PrepareCommonEsTitleKey

Wrapper for PrepareEsCommonKey SMC.

Takes an input 16-byte KeySource. Returns an output 16-byte AccessKey.

[3.0.0+] Now takes an input u32 Generation.

AllocateAesKeySlot

Returns an output u32 KeySlot.

Returns error 0xD01A if all keyslots are taken.

DeallocateAesKeySlot

Takes an input u32 KeySlot.

Returns error 0xD21A if the keyslot wasn't allocated by current session.

GetAesKeySlotAvailableEvent

Returns an output event handle for synchronizing with the AES keyslots.

SetBootReason

Takes an input u32 BootReason.

[4.0.0+] Returns 0xD41A if a value has been previously set without being gotten.

GetBootReason

Returns an output u32 BootReason.

[4.0.0+] Returns 0xD61A if a value has not previously been set and unsets the value after getting it.

spl:mig

This is "nn::spl::detail::ICryptoInterface".

Cmd	Name
0	#GetConfig
1	#ModularExponentiate
5	#SetConfig
7	#GenerateRandomBytes
11	#IsDevelopment
24	[3.0.0+] #SetBootReason
25	[3.0.0+] #GetBootReason
2	#GenerateAesKek
3	#LoadAesKey
4	#GenerateAesKey
14	#DecryptAesKey
15	#ComputeCtr
16	#ComputeCmac
21	[2.0.0+] #AllocateAesKeySlot
22	[2.0.0+] #DeallocateAesKeySlot
23	[2.0.0+] #GetAesKeySlotAvailableEvent

spl:fs

This is "nn::spl::detail::IFsInterface".

Cmd	Name
0	#GetConfig
1	#ModularExponentiate
5	#SetConfig
7	#GenerateRandomBytes
11	#IsDevelopment
24	[3.0.0+] #SetBootReason
25	[3.0.0+] #GetBootReason
2	#GenerateAesKek
3	#LoadAesKey
4	#GenerateAesKey
14	#DecryptAesKey
15	#ComputeCtr
16	#ComputeCmac
21	[2.0.0+] #AllocateAesKeySlot
22	[2.0.0+] #DeallocateAesKeySlot
23	[2.0.0+] #GetAesKeySlotAvailableEvent
9	#DecryptAndStoreGcKey
10	#DecryptGcMessage
12	#GenerateSpecificAesKey
19	#LoadPreparedAesKey
31	[5.0.0+] GetPackage2Hash

spl:ssl

This is "nn::spl::detail::ISslInterface".

Cmd	Name
0	#GetConfig
1	#ModularExponentiate
5	#SetConfig
7	#GenerateRandomBytes
11	#IsDevelopment
24	[3.0.0+] #SetBootReason
25	[3.0.0+] #GetBootReason
2	#GenerateAesKek
3	#LoadAesKey
4	#GenerateAesKey
14	#DecryptAesKey
15	#ComputeCtr
16	#ComputeCmac
21	[2.0.0+] #AllocateAesKeySlot
22	[2.0.0+] #DeallocateAesKeySlot
23	[2.0.0+] #GetAesKeySlotAvailableEvent
13	#DecryptDeviceUniqueData
26	[5.0.0+] DecryptAndStoreSslClientCertKey
27	[5.0.0+] ModularExponentiateWithSslClientCertKey

spl:es

This is "nn::spl::detail::IEsInterface".

Cmd	Name
0	#GetConfig
1	#ModularExponentiate
5	#SetConfig
7	#GenerateRandomBytes
11	#IsDevelopment
24	[3.0.0+] #SetBootReason
25	[3.0.0+] #GetBootReason
2	#GenerateAesKek
3	#LoadAesKey
4	#GenerateAesKey
14	#DecryptAesKey
15	#ComputeCtr
16	#ComputeCmac
21	[2.0.0+] #AllocateAesKeySlot
22	[2.0.0+] #DeallocateAesKeySlot
23	[2.0.0+] #GetAesKeySlotAvailableEvent
13	#DecryptDeviceUniqueData
17	#LoadEsDeviceKey
18	#PrepareEsTitleKey
20	[2.0.0+] #PrepareCommonEsTitleKey
28	[5.0.0+] DecryptAndStoreDrmDeviceCertKey
29	[5.0.0+] ModularExponentiateWithDrmDeviceCertKey
31	[6.0.0+] PrepareEsArchiveKey
32	[6.0.0+] #LoadPreparedAesKey
33	[18.0.0+]

spl:manu

This is "nn::spl::detail::IManuInterface".

Cmd	Name
0	#GetConfig
1	#ModularExponentiate
5	#SetConfig
7	#GenerateRandomBytes
11	#IsDevelopment
24	[3.0.0+] #SetBootReason
25	[3.0.0+] #GetBootReason
2	#GenerateAesKek
3	#LoadAesKey
4	#GenerateAesKey
14	#DecryptAesKey
15	#ComputeCtr
16	#ComputeCmac
21	[2.0.0+] #AllocateAesKeySlot
22	[2.0.0+] #DeallocateAesKeySlot
23	[2.0.0+] #GetAesKeySlotAvailableEvent
13	#DecryptDeviceUniqueData
30	[5.0.0+] ReencryptDeviceUniqueData

(S2) spl:ldn

This is "nn::spl::detail::ILdnInterface".

This has IPC max_sessions 1?

Cmd	Name
0	GenerateRandomBytes
1	GetConfig
2
3
4
5	GetConfigWithBuffer
7000
7001
7002
7003
7004
7005

The below 7000+ cmds take a KeySource (equivalent to NX-GenerateAesKey) and an u32. Bitmask 0x1F of the u32 is the Generation, 0x20 is valid but doesn't seem to do anything. Values >=0x21 throw error. A 0x10-byte outbuf is used for the output key. Cmd7004/Cmd7005 use a 0x20-byte outbuf. These are equivalent to GenerateAesKek+GenerateAesKey combined.

Cmd7000-Cmd7003 use NX keys, while Cmd7004/Cmd7005 use Ounce keys.

All of these use AES-ECB with the input KeySource, with the buffer as the output.

Cmd7000

Takes an input 16-byte KeySource, an input u32, and an output type-0xA buffer AesKey.

Generates a key using the NX-equivalent of the ldn Kek-action_keysource.

Cmd7001

Takes an input 16-byte KeySource, an input u32, and an output type-0xA buffer AesKey.

Generates a key using the NX-equivalent of the ldn Kek-data_keysource.

Cmd7002

Takes an input 16-byte KeySource, an input u32, and an output type-0xA buffer AesKey.

Cmd7003

Takes an input 16-byte KeySource, an input u32, and an output type-0xA buffer AesKey.

Cmd7004

Takes an input 32-byte KeySource, an input u32, and an output type-0xA buffer AesKey.

Ounce version of Cmd7000. ldn only uses the first 0x10-bytes of the output key.

Cmd7005

Takes an input 32-byte KeySource, an input u32, and an output type-0xA buffer AesKey.

Ounce version of Cmd7001. ldn only uses the first 0x10-bytes of the output key.