C#

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. C#

bool success = false;

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

Chilkat.Socket socket = new Chilkat.Socket();

// Connect to a server.
bool useTls = true;
int maxWaitMs = 2000;
success = socket.Connect("www.intel.com",443,useTls,maxWaitMs);
if (success == false) {
    Debug.WriteLine(socket.LastErrorText);
    return;
}

// 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.
Chilkat.Cert cert = new Chilkat.Cert();
socket.GetServerCert(cert);

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);

Debug.WriteLine("Expired: " + Convert.ToString(cert.Expired));
Debug.WriteLine("Revoked: " + Convert.ToString(cert.Revoked));
Debug.WriteLine("Signature Verified: " + Convert.ToString(cert.SignatureVerified));
Debug.WriteLine("Trusted Root: " + Convert.ToString(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