Test-WebServerSSLCert

-> This function/script is moved to GitHub!

Function Test-WebServerSSLCert {
[CmdletBinding()]
    param(
        [Parameter(Mandatory = $true, ValueFromPipeline = $true, Position = 0)]
        [string]$URL,
        [Parameter(Position = 1)]
        [ValidateRange(1,65535)]
        [int]$Port = 443,
        [Parameter(Position = 2)]
        [Net.WebProxy]$Proxy,
        [Parameter(Position = 3)]
        [int]$Timeout = 60000,
        [switch]$UseUserContext
    )
 
    If ($URL -like "https://*") {
        $ConnectString = "$url`:$port"
    } Else {
        $ConnectString = "https://$url`:$port"
    }
 
    $WebRequest = [Net.WebRequest]::Create($ConnectString)
    $WebRequest.Proxy = $Proxy
    $WebRequest.Credentials = $null
    $WebRequest.Timeout = $Timeout
    $WebRequest.AllowAutoRedirect = $true
    [Net.ServicePointManager]::ServerCertificateValidationCallback = {$true}
    try {$Response = $WebRequest.GetResponse()}
    catch {}
    if ($WebRequest.ServicePoint.Certificate -ne $null) {
        $Cert = [Security.Cryptography.X509Certificates.X509Certificate2]$WebRequest.ServicePoint.Certificate.Handle
        try {$SAN = ($Cert.Extensions | Where-Object {$_.Oid.Value -eq "2.5.29.17"}).Format(0) -split ", "}
        catch {$SAN = $null}
        $chain = New-Object Security.Cryptography.X509Certificates.X509Chain -ArgumentList (!$UseUserContext)
        [void]$chain.ChainPolicy.ApplicationPolicy.Add("1.3.6.1.5.5.7.3.1")
        $Status = $chain.Build($Cert)
        $ConnectionInformation = New-Object PSObject -Property ([Ordered]@{ 
            OriginalUri = $ConnectString; 
            ReturnedUri = $Response.ResponseUri; 
            Certificate = [Security.Cryptography.X509Certificates.X509Certificate2]$WebRequest.ServicePoint.Certificate; 
            Issuer = $WebRequest.ServicePoint.Certificate.Issuer; 
            Subject = $WebRequest.ServicePoint.Certificate.Subject; 
            SubjectAlternativeNames = $SAN; 
            CertificateIsValid = $Status; 
            Response = $Response; 
            ErrorInformation = $chain.ChainStatus | ForEach-Object {$_.Status} 
        })
        $ConnectionInformation.PSObject.TypeNames.Add("Indented.LDAP.ConnectionInformation")
        $ConnectionInformation
        $chain.Reset()
        [Net.ServicePointManager]::ServerCertificateValidationCallback = $null
    } else {
        Write-Error $Error[0]
    }
}