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Format-SecureBootUEFI

Wed Jan 30, 2019 6:00 pm

NAME Format-SecureBootUEFI



SYNOPSIS

Formats certificates or hashes into a content object that is returned and creates a file that is ready to be signed.





SYNTAX

Format-SecureBootUEFI [-AppendWrite] [-ContentFilePath <String>] [-SignableFilePath <System.String>] [-Time <System.String>] -Algorithm {sha1 | sha256 |

sha384 | sha512} -Hash <String[]> -Name {PK | KEK | db | dbx} -SignatureOwner <Guid> [<CommonParameters>]



Format-SecureBootUEFI [-AppendWrite] [-ContentFilePath <String>] [-FormatWithCert] [-SignableFilePath <System.String>] [-Time <System.String>]

-CertificateFilePath <String[]> -Name {PK | KEK | db | dbx} -SignatureOwner <Guid> [<CommonParameters>]



Format-SecureBootUEFI [-SignableFilePath <System.String>] [-Time <System.String>] -Delete -Name {PK | KEK | db | dbx} [<CommonParameters>]





DESCRIPTION

The Format-SecureBootUEFI cmdlet receives certificates or hashes as input and formats the input into a content object that is returned. The

Set-SecureBootUEFI cmdlet uses this object to update the variable. If you specify a signable file, this cmdlet creates a file that has the specified

name that has to be signed.



This cmdlet this runs on both UEFI and BIOS (non-UEFI) computers.





PARAMETERS

-Algorithm <String>

Specifies which algorithm to use if this cmdlet is formatting hashes. The acceptable values for this parameter are: SHA1, SHA256, SHA384, and SHA512.



Required? true

Position? named

Default value none

Accept pipeline input? false

Accept wildcard characters? false



-AppendWrite [<SwitchParameter>]

Indicates that the contents of the current variable are appended instead of overwritten.



Required? false

Position? named

Default value none

Accept pipeline input? false

Accept wildcard characters? false



-CertificateFilePath <String[]>

Specifies one or more files that each contain a certificate that is used to generate the content object.



If you specify only the name, the file must be in the current working directory. Otherwise, specify the full path of the file.



Required? true

Position? named

Default value none

Accept pipeline input? false

Accept wildcard characters? false



-ContentFilePath [<String>]

Specifies the name of the file that is created and contains the information for the content object that is generated by this cmdlet.



Required? false

Position? named

Default value none

Accept pipeline input? false

Accept wildcard characters? false



-Delete <SwitchParameter>

Indicates that this cmdlet creates a content object and the appropriate sign-able file that deletes the variable.



Required? true

Position? named

Default value none

Accept pipeline input? false

Accept wildcard characters? false



-FormatWithCert [<SwitchParameter>]

Indicates whether the certificate will be stored or just the public key. If this parameter is set, the whole certificate is stored in the content

object.



Required? false

Position? named

Default value none

Accept pipeline input? false

Accept wildcard characters? false



-Hash <String[]>

Specifies an array of hashes that are used to generate the content.



Required? true

Position? named

Default value none

Accept pipeline input? false

Accept wildcard characters? false



-Name <System.String>

Specifies the name of the UEFI environment variable. The acceptable values for this parameter are: PK, KEK, DB, and DBX.



Required? true

Position? named

Default value none

Accept pipeline input? true(ByValue)

Accept wildcard characters? false



-SignableFilePath [<System.String>]

Specifies the file that contains the contents of the data that is ready to be signed.



If only the name is specified, the file must be in the current working directory. Otherwise, specify the full path of the file.



Required? false

Position? named

Default value none

Accept pipeline input? false

Accept wildcard characters? false



-SignatureOwner <Guid>

Specifies the GUID of the signature owner.



Required? true

Position? named

Default value none

Accept pipeline input? false

Accept wildcard characters? false



-Time [<System.String>]

Specifies the timestamp that is used in the signature. Format this value as follows so that it is accepted as a DateTime object:



"2011-11-01T13:30:00Z"



Required? false

Position? named

Default value none

Accept pipeline input? false

Accept wildcard characters? false



<CommonParameters>

This cmdlet supports the common parameters: Verbose, Debug,

ErrorAction, ErrorVariable, WarningAction, WarningVariable,

OutBuffer, PipelineVariable, and OutVariable. For more information, see

about_CommonParameters (https:/go.microsoft.com/fwlink/?LinkID=113216).



INPUTS

System.String



This cmdlet accepts a string that represents the UEFI variable name that may be output from the Get-SecureBootUEFI cmdlet.





OUTPUTS

Microsoft.SecureBoot.Commands.UEFIFormattedVariable



This cmdlet returns a UEFIFormattedVariable object that contains information about the package that is built up to be set. The following members are

part of the UEFIFormattedVariable object:



-- A string named Name.

-- A string named Time.

-- A Boolean named AppendWrite.

-- An array of bytes named Content.



The UEFIFormattedVariable object can be used to pipe to the Set-SecureBootUEFI cmdlet.





Example 1: Format a private key



PS C:\\> Format-SecureBootUefi -Name PK -SignatureOwner 12345678-1234-1234-1234-123456789abc -CertificateFilePath PK.cer -SignableFilePath

GeneratedFileToSign.bin -Time 2011-11-01T13:30:00Z | Format-List

Name : PK

Time : 2011-11-01T13:30:00Z

AppendWrite : False

Content : {232, 102, 87, 60...}



This command formats the private key in PK.cer that is later piped to the Set-SecureBootUEFI cmdlet.





Example 2: Format a hash



PS C:\\> Format-SecureBootUEFI -Name DBX -SignatureOwner 12345678-1234-1234-1234-123456789abc -Algorithm SHA256 -Hash

0011223344556677889900112233445566778899001122334455667788990011 -SignableFilePath GeneratedFileToSign.bin -Time 2011-11-01T13:30:00Z -AppendWrite |

Format-List

Name : dbx

Time : 2011-11-01T13:30:00Z

AppendWrite : True

Content : {18, 165, 108, 130...}



This command formats the hash to beg appended to the DBX UEFI variable when the result is piped to the Set-SecureBootUEFI cmdlet.





Example 3: Format for a variable to be deleted



PS C:\\> Format-SecureBootUEFI -Name KEK -Delete -SignableFilePath GeneratedFileToSign.bin -Time 2011-11-01T13:30:00Z | Format-List

Name : KEK

Time : 2011-11-01T13:30:00Z

AppendWrite : False

Content :



This command formats the KEK UEFI variable being deleted when the result is piped into the Set-SecureBootUEFI cmdlet.







RELATED LINKS

Confirm-SecureBootUEFI

Get-SecureBootPolicy

Get-SecureBootUEFI

Set-SecureBootUEFI