CertificateIntrospection Class

Namespace: System.Net.Security
Assembly: System (in System.dll)

Note: This documentation pertains to a specific version of the .NET Framework. API behavior may vary across versions. Always consult the documentation for your target framework version.

Overview

The CertificateIntrospection class provides static methods for inspecting the properties of an X.509 certificate without requiring the certificate to be installed in a certificate store. This is useful for scenarios where you need to validate or extract information from certificates programmatically, such as during client authentication or secure communication setup.

This class is part of the .NET Framework and is designed to work with X.509 certificates, which are fundamental to establishing secure connections using protocols like TLS/SSL.

Remarks

CertificateIntrospection simplifies the process of accessing certificate details. Instead of complex cryptographic operations or store management, developers can directly query attributes like the subject name, issuer name, validity period, public key information, and extensions. This class promotes efficient and secure handling of certificate data in applications.

Methods

Example Usage

The following C# code demonstrates how to use the CertificateIntrospection class to retrieve information from an X.509 certificate.


using System;
using System.Security.Cryptography.X509;
using System.Net.Security;

public class CertificateInspector
{
    public static void InspectCertificate(string certificatePath)
    {
        try
        {
            // Load the certificate from a file
            X509Certificate2 certificate = new X509Certificate2(certificatePath);

            Console.WriteLine($"--- Certificate Details for: {certificate.FriendlyName} ---");

            // Get Subject Name
            string subjectName = CertificateIntrospection.GetSubjectName(certificate);
            Console.WriteLine($"Subject Name: {subjectName}");

            // Get Issuer Name
            string issuerName = CertificateIntrospection.GetIssuerName(certificate);
            Console.WriteLine($"Issuer Name: {issuerName}");

            // Get Validity Period
            var validityInfo = CertificateIntrospection.GetValidityPeriod(certificate);
            Console.WriteLine($"Validity Period:");
            foreach (var status in validityInfo)
            {
                Console.WriteLine($"- {status.Status}: {status.StatusInformation}");
            }
            Console.WriteLine($"Valid From: {certificate.NotBefore}");
            Console.WriteLine($"Valid To: {certificate.NotAfter}");

            // Get Public Key Info
            string publicKeyInfo = CertificateIntrospection.GetPublicKeyInfo(certificate);
            Console.WriteLine($"Public Key Info: {publicKeyInfo}");

            // Get Extensions
            X509ExtensionCollection extensions = CertificateIntrospection.GetExtensions(certificate);
            Console.WriteLine($"Number of Extensions: {extensions.Count}");
            foreach (X509Extension extension in extensions)
            {
                Console.WriteLine($"  - {extension.Oid.FriendlyName} ({extension.Oid.Value})");
            }

            Console.WriteLine("--------------------------------------------");
        }
        catch (Exception ex)
        {
            Console.WriteLine($"Error inspecting certificate: {ex.Message}");
        }
    }

    // Example usage within a Main method
    public static void Main(string[] args)
    {
        // Replace with the actual path to your certificate file
        string certFilePath = "path/to/your/certificate.cer";
        InspectCertificate(certFilePath);
    }
}

Requirements

Namespace: System.Net.Security
Assembly: System.dll

See Also