Functions/Uninstall-Certificate.ps1

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

function Uninstall-CCertificate
{
    <#
    .SYNOPSIS
    Removes a certificate from a store for the user or machine account.
     
    .DESCRIPTION
    The `Uninstall-CCertificate` function uses .NET's certificates API to remove a certificate from a given store for the machine or current user. Use the thumbprint to identify which certificate to remove. The thumbprint is unique to each certificate. The user performing the removal must have read and write permission on the store where the certificate is located.
 
    If the certificate isn't in the store, nothing happens, not even an error.
 
    To uninstall a certificate from a remote computer, use the `Session`parameter, which was added in Carbon 2.1.0. You can create a new session with the `New-PSSession` cmdlet.
 
    You can uninstall a certificate using just its thumbprint (this functionality is new in Carbon 2.5.0). `Uninstall-CCertificate` will search through all certificate locations and stores and uninstall all certificates that have the thumbprint. When you enumerate all certificates over a remoting session, you get a terminating `The system cannot open the device or file specified` error, so you can't delete a certificate with just a thumbprint over remoting.
 
    .EXAMPLE
    Uninstall-CCertificate -Thumbprint 570895470234023dsaaefdbcgbefa
 
    Demonstrates how to delete a certificate from all stores it is installed in. `Uninstall-CCertificate` searches every certificate stores and deletes all certificates with the given thumbprint. This functionality was added in Carbon 2.5.0.
 
    .EXAMPLE
    '570895470234023dsaaefdbcgbefa' | Uninstall-CCertificate
 
    Demonstrates that you can pipe a thumbprint to `Uninstall-CCertificate`. The certificate is uninstall from all stores it is in. This functionality was added in Carbon 2.5.0.
 
    .EXAMPLE
    Get-Item -Path 'cert:\LocalMachine\My\570895470234023dsaaefdbcgbefa' | Uninstall-CCertificate
 
    Demonstrates that you can pipe a certificate `Uninstall-CCertificate`. The certificate is uninstalled from all stores it is in. This functionality was added in Carbon 2.5.0.
 
    .EXAMPLE
    > Uninstall-CCertificate -Thumbprint 570895470234023dsaaefdbcgbefa -StoreLocation CurrentUser -StoreName My
     
    Removes the 570895470234023dsaaefdbcgbefa certificate from the current user's Personal certificate store.
     
    .EXAMPLE
    > $cert = Get-CCertificate -FriendlyName 'Carbon Testing Certificate' -StoreLocation LocalMachine -StoreName Root
    > Uninstall-CCertificate -Certificate $cert -StoreLocation LocalMachine -StoreName Root
     
    Removes the certificate with friendly name 'Carbon Testing Certificate' from the local machine's Trusted Root Certification Authorities store.
 
    .EXAMPLE
    Uninstall-CCertificate -Thumbprint 570895470234023dsaaefdbcgbefa -StoreLocation LocalMachine -StoreName 'SharePoint'
 
    Demonstrates how to uninstall a certificate from a custom, non-standard store.
 
    .EXAMPLE
    > Uninstall-CCertificate -Thumbprint 570895470234023dsaaefdbcgbefa -StoreLocation CurrentUser -StoreName My -Session (New-PSSession -ComputerName remote1,remote2)
     
    Demonstrates how to uninstall a certificate from a remote computer.
    #>

    [CmdletBinding(SupportsShouldProcess=$true,DefaultParameterSetName='ByThumbprint')]
    param(
        [Parameter(Mandatory=$true,ParameterSetName='ByThumbprint',ValueFromPipelineByPropertyName=$true,ValueFromPipeline=$true)]
        [Parameter(Mandatory=$true,ParameterSetName='ByThumbprintAndStoreName')]
        [Parameter(Mandatory=$true,ParameterSetName='ByThumbprintAndCustomStoreName')]
        [string]
        # The thumbprint of the certificate to remove.
        #
        # If you want to uninstall the certificate from all stores it is installed in, you can pipe the thumbprint to this parameter or you can pipe a certificate object. (This functionality was added in Carbon 2.5.0.)
        $Thumbprint,
        
        [Parameter(Mandatory=$true,ParameterSetName='ByCertificateAndStoreName')]
        [Parameter(Mandatory=$true,ParameterSetName='ByCertificateAndCustomStoreName')]
        [Security.Cryptography.X509Certificates.X509Certificate2]
        # The certificate to remove
        $Certificate,
        
        [Parameter(Mandatory=$true,ParameterSetName='ByThumbprintAndStoreName')]
        [Parameter(Mandatory=$true,ParameterSetName='ByThumbprintAndCustomStoreName')]
        [Parameter(Mandatory=$true,ParameterSetName='ByCertificateAndStoreName')]
        [Parameter(Mandatory=$true,ParameterSetName='ByCertificateAndCustomStoreName')]
        [Security.Cryptography.X509Certificates.StoreLocation]
        # The location of the certificate's store.
        $StoreLocation,
        
        [Parameter(Mandatory=$true,ParameterSetName='ByThumbprintAndStoreName')]
        [Parameter(Mandatory=$true,ParameterSetName='ByCertificateAndStoreName')]
        [Security.Cryptography.X509Certificates.StoreName]
        # The name of the certificate's store.
        $StoreName,

        [Parameter(Mandatory=$true,ParameterSetName='ByThumbprintAndCustomStoreName')]
        [Parameter(Mandatory=$true,ParameterSetName='ByCertificateAndCustomStoreName')]
        [string]
        # The name of the non-standard, custom store where the certificate should be un-installed.
        $CustomStoreName,

        [Parameter(ParameterSetName='ByThumbprintAndStoreName')]
        [Parameter(ParameterSetName='ByThumbprintAndCustomStoreName')]
        [Parameter(ParameterSetName='ByCertificateAndStoreName')]
        [Parameter(ParameterSetName='ByCertificateAndCustomStoreName')]
        [Management.Automation.Runspaces.PSSession[]]
        # Use the `Session` parameter to uninstall a certificate on remote computer(s) using PowerShell remoting. Use `New-PSSession` to create a session.
        #
        # Due to a bug in PowerShell, you can't remove a certificate by just its thumbprint over remoting. Using just a thumbprint requires us to enumerate through all installed certificates. When you do this over remoting, PowerShell throws a terminating `The system cannot open the device or file specified` error.
        #
        # This parameter was added in Carbon 2.1.0.
        $Session
    )
    
    process
    {
        Set-StrictMode -Version 'Latest'

        Use-CallerPreference -Cmdlet $PSCmdlet -Session $ExecutionContext.SessionState

        if( $PSCmdlet.ParameterSetName -like 'ByCertificate*' )
        {
            $Thumbprint = $Certificate.Thumbprint
        }
    
        $invokeCommandParameters = @{}
        if( $Session )
        {
            $invokeCommandParameters['Session'] = $Session
        }

        if( $PSCmdlet.ParameterSetName -eq 'ByThumbprint' )
        {
            # Must be in this order. Delete LocalMachine certs *first* so they don't show
            # up in CurrentUser stores. If you delete a certificate that "cascades" into
            # the CurrentUser store first, you'll get errors when running non-
            # interactively as SYSTEM.
            Get-ChildItem -Path 'Cert:\LocalMachine','Cert:\CurrentUser' -Recurse |
                Where-Object { -not $_.PsIsContainer } |
                Where-Object { $_.Thumbprint -eq $Thumbprint } |
                ForEach-Object {
                    $cert = $_
                    $description = $cert.FriendlyName
                    if( -not $description )
                    {
                        $description = $cert.Subject
                    }

                    $certPath = $_.PSPath | Split-Path -NoQualifier
                    Write-Verbose ('Uninstalling certificate ''{0}'' ({1}) at {2}.' -f $description,$cert.Thumbprint,$certPath)
                    $_
                } |
                Remove-Item
            return
        }

        Invoke-Command @invokeCommandParameters -ScriptBlock {
            [CmdletBinding()]
            param(
                [string]
                # The thumbprint of the certificate to remove.
                $Thumbprint,
        
                [Security.Cryptography.X509Certificates.StoreLocation]
                # The location of the certificate's store.
                $StoreLocation,
        
                # The name of the certificate's store.
                $StoreName,

                [string]
                # The name of the non-standard, custom store where the certificate should be un-installed.
                $CustomStoreName
            )

            Set-StrictMode -Version 'Latest'

            if( $CustomStoreName )
            {
                $storeNamePath = $CustomStoreName
            }
            else
            {
                $storeNamePath = $StoreName
                if( $StoreName -eq [Security.Cryptography.X509Certificates.StoreName]::CertificateAuthority )
                {
                    $storeNamePath = 'CA'
                }
            }

            $certPath = Join-Path -Path 'Cert:\' -ChildPath $StoreLocation
            $certPath = Join-Path -Path $certPath -ChildPath $storeNamePath
            $certPath = Join-Path -Path $certPath -ChildPath $Thumbprint

            if( -not (Test-Path -Path $certPath -PathType Leaf) )
            {
                Write-Debug -Message ('Certificate {0} not found.' -f $certPath)
                return
            }

            $cert = Get-Item -Path $certPath

            if( $CustomStoreName )
            {
                $store = New-Object 'Security.Cryptography.X509Certificates.X509Store' $CustomStoreName,$StoreLocation
            }
            else
            {
                $store = New-Object 'Security.Cryptography.X509Certificates.X509Store' ([Security.Cryptography.X509Certificates.StoreName]$StoreName),$StoreLocation
            }

            $store.Open( ([Security.Cryptography.X509Certificates.OpenFlags]::ReadWrite) )

            try
            {
                $target = $cert.FriendlyName
                if( -not $target )
                {
                    $target = $cert.Subject
                }

                if( $PSCmdlet.ShouldProcess( ("certificate {0} ({1})" -f $certPath,$target), "remove" ) )
                {
                    Write-Verbose ('Uninstalling certificate ''{0}'' ({1}) at {2}.' -f $target,$cert.Thumbprint,$certPath)
                    $store.Remove( $cert )
                }
            }
            finally
            {
                $store.Close()
            }
        } -ArgumentList $Thumbprint,$StoreLocation,$StoreName,$CustomStoreName
    }
}

Set-Alias -Name 'Remove-Certificate' -Value 'Uninstall-CCertificate'