fix(ps): add ConvertFrom-PEM to SetupUtils

.assets/scripts/modules_update.ps1

@@ -40,6 +40,7 @@ begin {
         'do-common'   = @{
             SetupUtils = @{
                 certs  = @(
+                    'ConvertFrom-PEM'
                     'ConvertTo-PEM'
                     'Get-Certificate'
                 )

modules/SetupUtils/Functions/certs.ps1

@@ -1,3 +1,56 @@
+function ConvertFrom-PEM {
+    [CmdletBinding()]
+    [OutputType([System.Security.Cryptography.X509Certificates.X509Certificate2[]])]
+    param (
+        [Parameter(Mandatory, ValueFromPipeline, ParameterSetName = 'FromString')]
+        [string]$InputObject,
+
+        [Parameter(Mandatory, Position = 0, ParameterSetName = 'FromPath')]
+        [ValidateScript({ Test-Path $_ -PathType 'Leaf' }, ErrorMessage = "'{0}' is not a valid file path.")]
+        [string]$Path
+    )
+
+    begin {
+        # list to store input certificate strings
+        $pemTxt = [System.Collections.Generic.List[string]]::new()
+        # hashset for storing parsed pem certificates
+        $pemSplit = [System.Collections.Generic.HashSet[string]]::new()
+        # list to store decoded certificates
+        $x509Certs = [System.Collections.Generic.List[Security.Cryptography.X509Certificates.X509Certificate2]]::new()
+    }
+
+    process {
+        switch ($PsCmdlet.ParameterSetName) {
+            FromPath {
+                # read certificate file
+                Resolve-Path $Path | ForEach-Object {
+                    $pemTxt.Add([IO.File]::ReadAllText($_))
+                }
+                continue
+            }
+            FromString {
+                $InputObject.ForEach({ $pemTxt.Add($_) })
+                continue
+            }
+        }
+    }
+
+    end {
+        # parse certificate string
+        [regex]::Matches(
+            [string]::Join("`n", $pemTxt).Replace("`r`n", "`n"),
+            '(?<=-{5}BEGIN[\w ]+CERTIFICATE-{5}\n)[\S\n]+(?=\n-{5}END[\w ]+CERTIFICATE-{5})'
+        ).Value.ForEach({ $pemSplit.Add($_) | Out-Null })
+        # convert PEM encoded certificates to X509 certificate objects
+        foreach ($pem in $pemSplit) {
+            $decCrt = [Security.Cryptography.X509Certificates.X509Certificate2]::new([Convert]::FromBase64String($pem))
+            $x509Certs.Add($decCrt)
+        }
+
+        return $x509Certs
+    }
+}
+
 function ConvertTo-PEM {
     [CmdletBinding()]
     [OutputType([System.Collections.Generic.List[string]])]

modules/SetupUtils/SetupUtils.psd1

@@ -12,7 +12,7 @@
     RootModule           = 'SetupUtils.psm1'
 
     # Version number of this module.
-    ModuleVersion        = '0.3.1'
+    ModuleVersion        = '0.4.0'
 
     # Supported PSEditions
     CompatiblePSEditions = @('Core')
@@ -71,6 +71,7 @@
     # Functions to export from this module, for best performance, do not use wildcards and do not delete the entry, use an empty array if there are no functions to export.
     FunctionsToExport    = @(
         # certs
+        'ConvertFrom-PEM'
         'ConvertTo-PEM'
         'Get-Certificate'
         # common

modules/SetupUtils/SetupUtils.psm1

@@ -7,6 +7,7 @@ $ErrorActionPreference = 'Stop'
 $exportModuleMemberParams = @{
     Function = @(
         # certs
+        'ConvertFrom-PEM'
         'ConvertTo-PEM'
         'Get-Certificate'
         # common