/** @file
Provides a helper functions for creating variable authenticated
payloads, signature lists related to secure boot keys.
Copyright (c) 2011 - 2018, Intel Corporation. All rights reserved.
(C) Copyright 2018 Hewlett Packard Enterprise Development LP
Copyright (c) 2021, ARM Ltd. All rights reserved.
Copyright (c) 2021, Semihalf All rights reserved.
Copyright (c) Microsoft Corporation.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#ifndef SECURE_BOOT_VARIABLE_LIB_H_
#define SECURE_BOOT_VARIABLE_LIB_H_
/**
Set the platform secure boot mode into "Custom" or "Standard" mode.
@param[in] SecureBootMode New secure boot mode: STANDARD_SECURE_BOOT_MODE or
CUSTOM_SECURE_BOOT_MODE.
@return EFI_SUCCESS The platform has switched to the special mode successfully.
@return other Fail to operate the secure boot mode.
--*/
EFI_STATUS
EFIAPI
SetSecureBootMode (
IN UINT8 SecureBootMode
);
/**
Fetches the value of SetupMode variable.
@param[out] SetupMode Pointer to UINT8 for SetupMode output
@retval other Error codes from GetVariable.
--*/
EFI_STATUS
EFIAPI
GetSetupMode (
OUT UINT8 *SetupMode
);
/**
Helper function to quickly determine whether SecureBoot is enabled.
@retval TRUE SecureBoot is verifiably enabled.
@retval FALSE SecureBoot is either disabled or an error prevented checking.
**/
BOOLEAN
EFIAPI
IsSecureBootEnabled (
VOID
);
/**
Create a EFI Signature List with data supplied from input argument.
The input certificates from KeyInfo parameter should be DER-encoded
format.
@param[out] SigListsSize A pointer to size of signature list
@param[out] SigListOut A pointer to a callee-allocated buffer with signature lists
@param[in] KeyInfoCount The number of certificate pointer and size pairs inside KeyInfo.
@param[in] KeyInfo A pointer to all certificates, in the format of DER-encoded,
to be concatenated into signature lists.
@retval EFI_SUCCESS Created signature list from payload successfully.
@retval EFI_NOT_FOUND Section with key has not been found.
@retval EFI_INVALID_PARAMETER Embedded key has a wrong format or input pointers are NULL.
@retval Others Unexpected error happens.
--*/
EFI_STATUS
EFIAPI
SecureBootCreateDataFromInput (
OUT UINTN *SigListsSize,
OUT EFI_SIGNATURE_LIST **SigListOut,
IN UINTN KeyInfoCount,
IN CONST SECURE_BOOT_CERTIFICATE_INFO *KeyInfo
);
/**
Create a time based data payload by concatenating the EFI_VARIABLE_AUTHENTICATION_2
descriptor with the input data. NO authentication is required in this function.
@param[in, out] DataSize On input, the size of Data buffer in bytes.
On output, the size of data returned in Data
buffer in bytes.
@param[in, out] Data On input, Pointer to data buffer to be wrapped or
pointer to NULL to wrap an empty payload.
On output, Pointer to the new payload date buffer allocated from pool,
it's caller's responsibility to free the memory when finish using it.
@param[in] Time Pointer to time information to created time based payload.
@retval EFI_SUCCESS Create time based payload successfully.
@retval EFI_OUT_OF_RESOURCES There are not enough memory resources to create time based payload.
@retval EFI_INVALID_PARAMETER The parameter is invalid.
@retval Others Unexpected error happens.
--*/
EFI_STATUS
EFIAPI
CreateTimeBasedPayload (
IN OUT UINTN *DataSize,
IN OUT UINT8 **Data,
IN EFI_TIME *Time
);
/**
Clears the content of the 'db' variable.
@retval EFI_OUT_OF_RESOURCES If memory allocation for EFI_VARIABLE_AUTHENTICATION_2 fails
while VendorGuid is NULL.
@retval other Errors from GetVariable2(), GetTime() and SetVariable()
--*/
EFI_STATUS
EFIAPI
DeleteDb (
VOID
);
/**
Clears the content of the 'dbx' variable.
@retval EFI_OUT_OF_RESOURCES If memory allocation for EFI_VARIABLE_AUTHENTICATION_2 fails
while VendorGuid is NULL.
@retval other Errors from GetVariable2(), GetTime() and SetVariable()
--*/
EFI_STATUS
EFIAPI
DeleteDbx (
VOID
);
/**
Clears the content of the 'dbt' variable.
@retval EFI_OUT_OF_RESOURCES If memory allocation for EFI_VARIABLE_AUTHENTICATION_2 fails
while VendorGuid is NULL.
@retval other Errors from GetVariable2(), GetTime() and SetVariable()
--*/
EFI_STATUS
EFIAPI
DeleteDbt (
VOID
);
/**
Clears the content of the 'KEK' variable.
@retval EFI_OUT_OF_RESOURCES If memory allocation for EFI_VARIABLE_AUTHENTICATION_2 fails
while VendorGuid is NULL.
@retval other Errors from GetVariable2(), GetTime() and SetVariable()
--*/
EFI_STATUS
EFIAPI
DeleteKEK (
VOID
);
/**
Clears the content of the 'PK' variable.
@retval EFI_OUT_OF_RESOURCES If memory allocation for EFI_VARIABLE_AUTHENTICATION_2 fails
while VendorGuid is NULL.
@retval other Errors from GetVariable2(), GetTime() and SetVariable()
--*/
EFI_STATUS
EFIAPI
DeletePlatformKey (
VOID
);
/**
This function will delete the secure boot keys, thus
disabling secure boot.
@return EFI_SUCCESS or underlying failure code.
**/
EFI_STATUS
EFIAPI
DeleteSecureBootVariables (
VOID
);
/**
A helper function to take in a variable payload, wrap it in the
proper authenticated variable structure, and install it in the
EFI variable space.
@param[in] VariableName The name of the key/database.
@param[in] VendorGuid The namespace (ie. vendor GUID) of the variable
@param[in] DataSize Size parameter for target secure boot variable.
@param[in] Data Pointer to signature list formatted secure boot variable content.
@retval EFI_SUCCESS The enrollment for authenticated variable was successful.
@retval EFI_OUT_OF_RESOURCES There are not enough memory resources to create time based payload.
@retval EFI_INVALID_PARAMETER The parameter is invalid.
@retval Others Unexpected error happens.
**/
EFI_STATUS
EFIAPI
EnrollFromInput (
IN CHAR16 *VariableName,
IN EFI_GUID *VendorGuid,
IN UINTN DataSize,
IN VOID *Data
);
/**
Similar to DeleteSecureBootVariables, this function is used to unilaterally
force the state of related SB variables (db, dbx, dbt, KEK, PK, etc.) to be
the built-in, hardcoded default vars.
@param[in] SecureBootPayload Payload information for secure boot related keys.
@retval EFI_SUCCESS SecureBoot keys are now set to defaults.
@retval EFI_ABORTED SecureBoot keys are not empty. Please delete keys first
or follow standard methods of altering keys (ie. use the signing system).
@retval EFI_SECURITY_VIOLATION Failed to create the PK.
@retval Others Something failed in one of the subfunctions.
**/
EFI_STATUS
EFIAPI
SetSecureBootVariablesToDefault (
IN CONST SECURE_BOOT_PAYLOAD_INFO *SecureBootPayload
);
#endif