Verify SSL Server Certificate

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

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Dim socket As New Chilkat.Socket()

Dim success As Boolean
success = socket.UnlockComponent("Anything for 30-day trial")
If (success <> true) Then
    MsgBox("Failed to unlock component")
    Exit Sub
End If


Dim ssl As Boolean
ssl = true
Dim maxWaitMillisec As Long
maxWaitMillisec = 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 Long
sslServerPort = 443

'  Connect to the SSL server:
success = socket.Connect(sslServerHost,sslServerPort,ssl,maxWaitMillisec)
If (success <> true) Then
    MsgBox(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 (Not (cert Is Nothing )) Then

    TextBox1.Text = TextBox1.Text & "Server Certificate:" & vbCrLf
    TextBox1.Text = TextBox1.Text & "Distinguished Name: " _
         & cert.SubjectDN & vbCrLf
    TextBox1.Text = TextBox1.Text & "Common Name: " _
         & cert.SubjectCN & vbCrLf
    TextBox1.Text = TextBox1.Text & "Issuer Distinguished Name: " _
         & cert.IssuerDN & vbCrLf
    TextBox1.Text = TextBox1.Text & "Issuer Common Name: " _
         & cert.IssuerCN & vbCrLf

    bExpired = cert.IsExpired()
    bRevoked = cert.Revoked
    bSignatureVerified = cert.SignatureVerified
    bTrustedRoot = cert.TrustedRoot

    TextBox1.Text = TextBox1.Text & "Expired: " _
         & bExpired & vbCrLf
    TextBox1.Text = TextBox1.Text & "Revoked: " _
         & bRevoked & vbCrLf
    TextBox1.Text = TextBox1.Text & "Signature Verified: " _
         & bSignatureVerified & vbCrLf
    TextBox1.Text = TextBox1.Text & "Trusted Root: " _
         & bTrustedRoot & vbCrLf


End If


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