(VB.NET) Verify SSL Server Certificate

Demonstrates how to connect to an SSL server and verify its SSL certificate.

Chilkat .NET Downloads Chilkat .NET Framework Chilkat for .NET Core

' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

Dim socket As New Chilkat.Socket

Dim ssl As Boolean = True
Dim maxWaitMillisec As Integer = 20000

' The SSL server hostname may be an IP address, a domain name,
' or "localhost". 
Dim sslServerHost As String
sslServerHost = "www.paypal.com"
Dim sslServerPort As Integer = 443

' Connect to the SSL server:
Dim success As Boolean = socket.Connect(sslServerHost,sslServerPort,ssl,maxWaitMillisec)
If (success <> True) Then
    Debug.WriteLine(socket.LastErrorText)
    Exit Sub
End If


Dim cert As Chilkat.Cert

Dim bExpired As Boolean
Dim bRevoked As Boolean
Dim bSignatureVerified As Boolean
Dim bTrustedRoot As Boolean

cert = socket.GetSslServerCert()
If (socket.LastMethodSuccess <> False) Then

    Debug.WriteLine("Server Certificate:")
    Debug.WriteLine("Distinguished Name: " & cert.SubjectDN)
    Debug.WriteLine("Common Name: " & cert.SubjectCN)
    Debug.WriteLine("Issuer Distinguished Name: " & cert.IssuerDN)
    Debug.WriteLine("Issuer Common Name: " & cert.IssuerCN)

    bExpired = cert.Expired
    bRevoked = cert.Revoked
    bSignatureVerified = cert.SignatureVerified
    bTrustedRoot = cert.TrustedRoot

    Debug.WriteLine("Expired: " & bExpired)
    Debug.WriteLine("Revoked: " & bRevoked)
    Debug.WriteLine("Signature Verified: " & bSignatureVerified)
    Debug.WriteLine("Trusted Root: " & bTrustedRoot)


End If


' Close the connection with the server
' Wait a max of 20 seconds (20000 millsec)
success = socket.Close(20000)