Added Public Function Find-Certificate

CHANGELOG.md

@@ -7,6 +7,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Added public function `Find-Certificate` that returns one or more
+  certificates using certificate selector parameters - [Issue #100](https://github.com/dsccommunity/DscResource.Common/issues/100)
+  - Related to [CertificateDsc Issue #272](https://github.com/dsccommunity/CertificateDsc/issues/272).
+
 ## [0.14.0] - 2022-12-31
 
 ### Added

README.md

@@ -521,6 +521,82 @@ ConvertTo-HashTable -CimInstance $cimInstance
 This creates a array om CimInstances of the class name MSFT_KeyValuePair
 and passes it to ConvertTo-HashTable which returns a hashtable.
 
+### `Find-Certificate`
+
+A common function to find certificates based on multiple search filters,
+including, but not limited to: Thumbprint, Friendly Name, DNS Names,
+Key Usage, Issuers, etc.
+
+Locates one or more certificates using the passed certificate selector
+parameters.
+
+If more than one certificate is found matching the selector criteria,
+they will be returned in order of descending expiration date.
+
+#### Syntax
+
+```plaintext
+Find-Certificate [[-Thumbprint] <String>] [[-FriendlyName] <String>]
+[[-Subject] <String>] [[-DNSName] <String[]>] [[-Issuer] <String>]
+[[-KeyUsage] <String[]>] [[-EnhancedKeyUsage] <String[]>] [[-Store] <String>]
+[[-AllowExpired] <Boolean>] [<CommonParameters>]
+```
+
+### Outputs
+
+**System.Security.Cryptography.X509Certificates.X509Certificate2**
+
+### Example
+
+```PowerShell
+Find-Certificate -Thumbprint '1111111111111111111111111111111111111111'
+```
+
+Return certificate that matches thumbprint.
+
+```PowerShell
+Find-Certificate -KeyUsage 'DataEncipherment', 'DigitalSignature'
+```
+
+Return certificate(s) that have specific key usage.
+
+```PowerShell
+Find-Certificate -DNSName 'www.fabrikam.com', 'www.contoso.com'
+```
+
+Return certificate(s) filtered on specific DNS Names.
+
+```PowerShell
+find-certificate -Subject 'CN=contoso, DC=com'
+```
+
+Return certificate(s) with specific subject.
+
+```PowerShell
+find-certificate -Issuer 'CN=contoso-ca, DC=com' -AllowExpired $true
+```
+
+Return all certificates from specific issuer, including expired certificates.
+
+```PowerShell
+$findCertSplat = @{
+    EnhancedKeyUsage = @('Client authentication','Server Authentication')
+    AllowExpired = $true
+}
+
+Find-Certificate @findCertSplat
+```
+
+Return all certificates that can be used for server or client authentication,
+including expired certificates.
+
+```PowerShell
+Find-Certificate -FriendlyName 'My SSL Cert'
+```
+
+Return certificate based on FriendlyName.
+
+
 ### `Get-ComputerName`
 
 Returns the computer name cross-plattform. The variable `$env:COMPUTERNAME`

source/Public/Find-Certificate.ps1

@@ -0,0 +1,189 @@
+<#
+    .SYNOPSIS
+        Locates one or more certificates using the passed certificate selector parameters.
+
+        If more than one certificate is found matching the selector criteria, they will be
+        returned in order of descending expiration date.
+
+    .DESCRIPTION
+        A common function to find certificates based on multiple search filters, including,
+        but not limited to: Thumbprint, Friendly Name, DNS Names, Key Usage, Issuers, etc.
+
+    .PARAMETER Thumbprint
+        The thumbprint of the certificate to find.
+
+    .PARAMETER FriendlyName
+        The friendly name of the certificate to find.
+
+    .PARAMETER Subject
+        The subject of the certificate to find.
+
+    .PARAMETER DNSName
+        The subject alternative name of the certificate to export must contain these values.
+
+    .PARAMETER Issuer
+        The issuer of the certificate to find.
+
+    .PARAMETER KeyUsage
+        The key usage of the certificate to find must contain these values.
+
+    .PARAMETER EnhancedKeyUsage
+        The enhanced key usage of the certificate to find must contain these values.
+
+    .PARAMETER Store
+        The Windows Certificate Store Name to search for the certificate in.
+        Defaults to 'My'.
+
+    .PARAMETER AllowExpired
+        Allows expired certificates to be returned.
+
+    .EXAMPLE
+        Find-Certificate -Thumbprint '1111111111111111111111111111111111111111'
+
+        Return certificate that matches thumbprint.
+
+    .EXAMPLE
+        Find-Certificate -KeyUsage 'DataEncipherment', 'DigitalSignature'
+
+        Return certificate(s) that have specific key usage.
+
+    .EXAMPLE
+        Find-Certificate -DNSName 'www.fabrikam.com', 'www.contoso.com'
+
+        Return certificate(s) filtered on specific DNS Names.
+
+    .EXAMPLE
+        find-certificate -Subject 'CN=contoso, DC=com'
+
+        Return certificate(s) with specific subject.
+
+    .EXAMPLE
+        find-certificate -Issuer 'CN=contoso-ca, DC=com' -AllowExpired $true
+
+        Return all certificates from specific issuer, including expired certificates.
+
+    .EXAMPLE
+        Find-Certificate -EnhancedKeyUsage 'Server Authentication' -AllowExpired $true
+
+        Return all certificates that can be used for "Server Authentication", including expired certificates.
+
+    .EXAMPLE
+        Find-Certificate -FriendlyName 'My IIS Site SSL Cert'
+
+        Return certificate based on FriendlyName.
+
+#>
+function Find-Certificate
+{
+    [CmdletBinding()]
+    [OutputType([System.Security.Cryptography.X509Certificates.X509Certificate2[]])]
+    param
+    (
+        [Parameter()]
+        [System.String]
+        $Thumbprint,
+
+        [Parameter()]
+        [System.String]
+        $FriendlyName,
+
+        [Parameter()]
+        [System.String]
+        $Subject,
+
+        [Parameter()]
+        [System.String[]]
+        $DNSName,
+
+        [Parameter()]
+        [System.String]
+        $Issuer,
+
+        [Parameter()]
+        [System.String[]]
+        $KeyUsage,
+
+        [Parameter()]
+        [System.String[]]
+        $EnhancedKeyUsage,
+
+        [Parameter()]
+        [System.String]
+        $Store = 'My',
+
+        [Parameter()]
+        [Boolean]
+        $AllowExpired = $false
+    )
+
+    $certPath = Join-Path -Path 'Cert:\LocalMachine' -ChildPath $Store
+
+    if (-not (Test-Path -Path $certPath))
+    {
+        # The Certificte Path is not valid
+        New-InvalidArgumentException `
+            -Message ($script:localizedData.CertificatePathError -f $certPath) `
+            -ArgumentName 'Store'
+    } # if
+
+    # Assemble the filter to use to select the certificate
+    $certFilters = @()
+
+    if ($PSBoundParameters.ContainsKey('Thumbprint'))
+    {
+        $certFilters += @('($_.Thumbprint -eq $Thumbprint)')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('FriendlyName'))
+    {
+        $certFilters += @('($_.FriendlyName -eq $FriendlyName)')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('Subject'))
+    {
+        $certFilters += @('($_.Subject -eq $Subject)')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('Issuer'))
+    {
+        $certFilters += @('($_.Issuer -eq $Issuer)')
+    } # if
+
+    if (-not $AllowExpired)
+    {
+        $certFilters += @('(((Get-Date) -le $_.NotAfter) -and ((Get-Date) -ge $_.NotBefore))')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('DNSName'))
+    {
+        $certFilters += @('(@(Compare-Object -ReferenceObject $_.DNSNameList.Unicode -DifferenceObject $DNSName | Where-Object -Property SideIndicator -eq "=>").Count -eq 0)')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('KeyUsage'))
+    {
+        $certFilters += @('(@(Compare-Object -ReferenceObject ($_.Extensions.KeyUsages -split ", ") -DifferenceObject $KeyUsage | Where-Object -Property SideIndicator -eq "=>").Count -eq 0)')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('EnhancedKeyUsage'))
+    {
+        $certFilters += @('(@(Compare-Object -ReferenceObject ($_.EnhancedKeyUsageList.FriendlyName) -DifferenceObject $EnhancedKeyUsage | Where-Object -Property SideIndicator -eq "=>").Count -eq 0)')
+    } # if
+
+    # Join all the filters together
+    $certFilterScript = '(' + ($certFilters -join ' -and ') + ')'
+
+    Write-Verbose `
+        -Message ($script:localizedData.SearchingForCertificateUsingFilters -f $store, $certFilterScript) `
+        -Verbose
+
+    $certs = Get-ChildItem -Path $certPath |
+        Where-Object -FilterScript ([ScriptBlock]::Create($certFilterScript))
+
+    # Sort the certificates
+    if ($certs.count -gt 1)
+    {
+        $certs = $certs | Sort-Object -Descending -Property 'NotAfter'
+    } # if
+
+    return $certs
+} # end function Find-Certificate

source/en-US/DscResource.Common.strings.psd1

@@ -43,4 +43,8 @@ ConvertFrom-StringData @'
     ## Assert-RequiredCommandParameter
     RequiredCommandParameter_SpecificParametersMustAllBeSet = The parameters '{0}' must all be specified. (DRC0044)
     RequiredCommandParameter_SpecificParametersMustAllBeSetWhenParameterExist = The parameters '{0}' must all be specified if either parameter '{1}' is specified. (DRC0045)
+
+    ## Find-Certificate
+    CertificatePathError = Certificate Path '{0}' is not valid. (DRC0046)
+    SearchingForCertificateUsingFilters = Looking for certificate in Store '{0}' using filter '{1}'. (DRC0047)
 '@