Visual Basic 6.0

Examine SSL/TLS Server Certificate

See more Socket/SSL/TLS Examples

Demonstrates how an application can examine and check a server's SSL/TLS certificate. Visual Basic 6.0

Dim success As Long
success = 0

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

Dim socket As New ChilkatSocket

' Connect to a server.
Dim useTls As Long
useTls = 1
Dim maxWaitMs As Long
maxWaitMs = 2000
success = socket.Connect("www.intel.com",443,useTls,maxWaitMs)
If (success = 0) Then
    Debug.Print socket.LastErrorText
    Exit Sub
End If

' If we get here, the TLS connection ws made..
' In any SSL/TLS handshake, the server sends its certificate in a TLS handshake message.
' Chilkat will keep it cached within the object that made the connection.
' Get the server's cert and examine a few things.
Dim cert As New ChilkatCert
success = socket.GetServerCert(cert)

Debug.Print "Distinguished Name: " & cert.SubjectDN
Debug.Print "Common Name: " & cert.SubjectCN
Debug.Print "Issuer Distinguished Name: " & cert.IssuerDN
Debug.Print "Issuer Common Name: " & cert.IssuerCN

Debug.Print "Expired: " & cert.Expired
Debug.Print "Revoked: " & cert.Revoked
Debug.Print "Signature Verified: " & cert.SignatureVerified
Debug.Print "Trusted Root: " & cert.TrustedRoot

' Sample output:

' Distinguished Name: C=US, ST=California, O=Intel Corporation, CN=*.intel.com
' Common Name: *.intel.com
' Issuer Distinguished Name: C=GB, ST=Greater Manchester, L=Salford, O=Sectigo Limited, CN=Sectigo RSA Organization Validation Secure Server CA
' Issuer Common Name: Sectigo RSA Organization Validation Secure Server CA
' Expired: False
' Revoked: False
' Signature Verified: True
' Trusted Root: True