Nintendo Switch Brew

Secure Monitor: Difference between revisions

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= Secure Monitor calls =
= Secure Monitor Calls =
The secure monitor provides two top level handlers of which each provides a range of sub handlers.
The secure monitor provides two top level handlers of which each provides a range of sub handlers.


Secure Monitor calls follow the ARM SMC calling convention up to a small change:
Secure Monitor calls follow the ARM SMC calling convention with a small change:
{| class=wikitable
{| class=wikitable
! Bit number || Bit mask || Description
! Bits || Description
|-
|-
| 31 || 0x80000000 || Set to 0 means Yielding Call; Set to 1 means Fast Call.
| 0-7 || Function Number
|-
|-
| 30 || 0x40000000 || Set to 0 means SMC32 convention; Set to 1 means SMC64.
| 8-15 || Argument Type
|-
|-
| 29-24 || 0x3F000000 || Service Call ranges.
| 16-23 || Reserved
|-
|-
| 23-16 || 0x00FF0000 || Must be zero.
| 24-29 || Call Range
|-
|-
| 15-8 || 0x0000FF00 || Argument type. This is different from the ARM SMC calling convention.
| 30 || Call Convention (0 = SMC32, 1 = SMC64)
|-
|-
| 7-0 || 0x000000FF || Function number within the range call type.
| 31 || Call Type (0 = Yielding Call, 1 = Fast Call)
|}
|}


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| 0xC3000404 || GetResultData
| 0xC3000404 || GetResultData
|-
|-
| 0xC3000E05 || ExpMod
| 0xC3000E05 || ModularExponentiate
|-
|-
| 0xC3000006 || [[#GenerateRandomBytes]] (same as in [[#FunctionId1]])
| 0xC3000006 || [[#GenerateRandomBytes]] (same as in [[#FunctionId1]])
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| 0xC300040B || [[#ComputeCmac]]
| 0xC300040B || [[#ComputeCmac]]
|-
|-
| [1.0.0-4.1.0] 0xC300100C || [[#ImportEsKey]]
| [1.0.0-4.1.0] 0xC300100C || [[#DecryptAndImportEsDeviceKey]]
|-
|-
| [5.0.0+] 0xC300D60C || [[#ReEncryptRsaPrivateKey]]
| [5.0.0+] 0xC300D60C || [[#ReencryptDeviceUniqueData]]
|-
|-
| [1.0.0-4.1.0] 0xC300100D || [[#DecryptRsaPrivateKey]]
| 0xC300100D || [[#DecryptDeviceUniqueData]]
|-
|-
| [5.0.0+] 0xC300100D || [[#DecryptOrImportRsaPrivateKey]]
| [1.0.0-4.1.0] 0xC300100E || [[#DecryptAndImportLotusKey]]
|-
|-
| [1.0.0-4.1.0] 0xC300100E || [[#ImportSecureExpModKey]]
| 0xC300060F || [[#ModularExponentiateByStorageKey]]
|-
|-
| 0xC300060F || [[#SecureExpMod]]
| 0xC3000610 || [[#PrepareEsDeviceUniqueKey]]
|-
|-
| 0xC3000610 || [[#UnwrapTitleKey]]
| 0xC3000011 || [[#LoadPreparedAesKey]]
|-
|-
| 0xC3000011 || [[#LoadTitleKey]]
| 0xC3000012 || [2.0.0+] [[#PrepareEsCommonKey]]
|-
| 0xC3000012 || [2.0.0+] [[#UnwrapCommonTitleKey]]
|}
|}


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Calculates CMAC over input data.
Calculates CMAC over input data.


=== ImportEsKey ===
=== DecryptAndImportEsDeviceKey ===
Takes a session kek created with [[#GenerateAesKek]], a wrapped AES key, and a wrapped RSA private key.
Takes a session kek created with [[#GenerateAesKek]], a wrapped AES key, and a wrapped RSA private key.


The session kek must have been created with [[#CryptoUsecase|CryptoUsecase TitleKey]].
The session kek must have been created with [[#CryptoUsecase|CryptoUsecase TitleKey]].


[5.0.0] This function was removed and replaced with [[#ReEncryptRsaPrivateKey]].
[5.0.0] This function was removed and replaced with [[#ReencryptDeviceUniqueData]].


=== ReEncryptRsaPrivateKey ===
=== ReencryptDeviceUniqueData ===
Takes in two session keks created with [[#GenerateAesKek]], two wrapped AES keys, an enum member, and a wrapped RSA private key.
Takes in two session keks created with [[#GenerateAesKek]], two wrapped AES keys, an enum member, and a wrapped RSA private key.


Decrypts and validates the wrapped RSA private key with the first kek/wrapped key, and re-encrypts it with the second if valid.
Decrypts and validates the wrapped RSA private key with the first kek/wrapped key, and re-encrypts it with the second if valid.


The re-encrypted key is then passed to the user, for use with [[#DecryptOrImportRsaPrivateKey]].
The re-encrypted key is then passed to the user, for use with [[#DecryptDeviceUniqueData]].


=== DecryptRsaPrivateKey ===
=== DecryptDeviceUniqueData ===
Takes a session kek created with [[#GenerateAesKek]], a wrapped AES key, an enum member, and a wrapped RSA private key.
Takes a session kek created with [[#GenerateAesKek]], a wrapped AES key, an enum member, and a wrapped RSA private key.


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[4.0.0+] The SMC handler when certain conditions pass and FunctionId0==0xC300100D now returns error 0x6 instead of calling the handler funcptr.
[4.0.0+] The SMC handler when certain conditions pass and FunctionId0==0xC300100D now returns error 0x6 instead of calling the handler funcptr.


[5.0.0+] This function was replaced by [[#DecryptOrImportRsaPrivateKey]].
[5.0.0+] This function now takes an additional input [[#DecryptOrImportMode]]. This extends the original functionality to enable importing private keys into the security engine instead of decrypting them.
 
=== DecryptOrImportRsaPrivateKey ===
This function replaced [[#DecryptRsaPrivateKey]] in [[5.0.0]], adding an additional [[#DecryptOrImportMode]].
 
This SMC extends DecryptRsaPrivateKey's original functionality to enable importing private keys into the security engine instead of decrypting them, when certain enum members are passed.


=== ImportSecureExpModKey ===
=== DecryptAndImportLotusKey ===
Takes a session kek created with [[#GenerateAesKek]], and a wrapped RSA key.
Takes a session kek created with [[#GenerateAesKek]], and a wrapped RSA key.


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[5.0.0] This function was removed.
[5.0.0] This function was removed.


=== SecureExpMod ===
=== ModularExponentiateByStorageKey ===
Performs an ExpMod operation using an exponent previously loaded with the [[#ImportSecureExpModKey]] command.
Performs an ExpMod operation using an exponent previously loaded with the [[#DecryptAndImportLotusKey]] command.


[5.0.0+] This now uses any exponent previously loaded with [[#DecryptOrImportRsaPrivateKey]] and takes an [[#SecureExpModMode]].
[5.0.0+] This now uses any exponent previously loaded with [[#DecryptDeviceUniqueData]] and takes an [[#SecureExpModMode]].


=== UnwrapTitleKey ===
=== PrepareEsDeviceUniqueKey ===
Takes an Rsa-Oaep-wrapped TitleKey, an RSA Public Key, and a label hash.
Takes an Rsa-Oaep-wrapped TitleKey, an RSA Public Key, and a label hash.


Performs an ExpMod operation using an exponent previously loaded with the [[#ImportEsKey]] command, and then validates/extracts a Titlekey from the resulting message.
Performs an ExpMod operation using an exponent previously loaded with the [[#DecryptAndImportEsDeviceKey]] command, and then validates/extracts a Titlekey from the resulting message.


Returns a session-unique AES key especially for use in [[#LoadTitleKey]].
Returns a session-unique AES key especially for use in [[#LoadTitleKey]].


[5.0.0+] This now uses any exponent previously loaded with [[#DecryptOrImportRsaPrivateKey]].
[5.0.0+] This now uses any exponent previously loaded with [[#DecryptDeviceUniqueData]].


=== LoadTitleKey ===
=== LoadPreparedAesKey ===
Takes a session-unique AES key from [[#UnwrapCommonTitleKey]] or [[#UnwrapTitleKey]].
Takes a session-unique AES key from [[#PrepareEsCommonKey]] or [[#PrepareEsDeviceUniqueKey]].


=== UnwrapCommonTitleKey ===
=== PrepareEsCommonKey ===
Takes an AES-wrapped TitleKey and returns a sealed AES key.
Takes an AES-wrapped common TitleKey and returns a sealed AES key.


== FunctionId1 ==
== FunctionId1 ==
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! Value || Name
! Value || Name
|-
|-
| 0xC4000001 || [[#CpuSuspend]]
| 0xC4000001 || [[#SuspendCpu]]
|-
|-
| 0x84000002 || [[#CpuOff]]
| 0x84000002 || [[#PowerOffCpu]]
|-
|-
| 0xC4000003 || [[#CpuOn]]
| 0xC4000003 || [[#PowerOnCpu]]
|-
|-
| 0xC3000004 || [[#GetConfig]] (same as in [[#FunctionId0]])
| 0xC3000004 || [[#GetConfig]] (same as in [[#FunctionId0]])
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| 0xC3000005 || [[#GenerateRandomBytes]] (same as in [[#FunctionId0]])
| 0xC3000005 || [[#GenerateRandomBytes]] (same as in [[#FunctionId0]])
|-
|-
| 0xC3000006 || [[#Panic]]
| 0xC3000006 || [[#ShowError]]
|-
|-
| 0xC3000007 || [2.0.0+] [[#ConfigureCarveout]]
| 0xC3000007 || [2.0.0+] [[#SetKernelCarveoutRegion]]
|-
|-
| 0xC3000008 || [2.0.0+] [[#ReadWriteRegister]]
| 0xC3000008 || [2.0.0+] [[#ReadWriteRegister]]
|}
|}


=== CpuSuspend ===
=== SuspendCpu ===
Takes an u64 '''PowerState''', an u64 '''EntrypointAddress''' and an u64 '''ContextId'''. No output.
Takes an u64 '''PowerState''', an u64 '''EntrypointAddress''' and an u64 '''ContextId'''. No output.


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The kernel calls this SMC on shutdown with '''PowerState''' set to 0x0201001B (power level: 0x02==system; power type: 0x01==powerdown; ID: 0x1B).
The kernel calls this SMC on shutdown with '''PowerState''' set to 0x0201001B (power level: 0x02==system; power type: 0x01==powerdown; ID: 0x1B).


=== CpuOff ===
=== PowerOffCpu ===
No input/output.
No input/output.


Turns off the CPU (CPU1, CPU2 or CPU3).
Turns off the CPU (CPU1, CPU2 or CPU3).


=== CpuOn ===
=== PowerOnCpu ===
Takes an u64 '''TargetCpu''', an u64 '''EntrypointAddress''' and an u64 '''ContextId'''. Returns [[#Result]].
Takes an u64 '''TargetCpu''', an u64 '''EntrypointAddress''' and an u64 '''ContextId'''. Returns [[#Result]].


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The kernel limits '''Size''' to 0x38 (for fitting in return registers).
The kernel limits '''Size''' to 0x38 (for fitting in return registers).


=== Panic ===
=== ShowError ===
Takes an u32 '''Color''' and issues a system panic.
Takes an u32 '''Color''' and issues a system panic.


The kernel always calls this with '''Color''' set to 0xF00.
The kernel always calls this with '''Color''' set to 0xF00.


=== ConfigureCarveout ===
=== SetKernelCarveoutRegion ===
Takes an u64 '''Index''', an u64 '''Address''' and an u64 '''Size'''. Returns [[#Result]].
Takes an u64 '''Index''', an u64 '''Address''' and an u64 '''Size'''. Returns [[#Result]].


Retrieved from "https://switchbrew.org/wiki/Secure_Monitor"