Extension methods for X509 Certificates

CertificateHelper.cs

namespace BitWise.Utilities.Certificate
{
    using System;
    using System.Globalization;
    using System.Linq;
    using System.Security.Cryptography.X509Certificates;
    //using log4net;

    /// <summary>
    /// Extension methods for X509 certificates
    /// </summary>
    static class CertificateHelper
    {
        /// <summary>
        /// Formatted thumbprint.
        /// </summary>
        /// <param name="x509">The X509Certificate.</param>
        /// <returns></returns>
        public static string FormattedThumbprint(this X509Certificate x509)
        {
            return string.Join(" ", x509.GetCertHash().Select(h => h.ToString("x2")));
        }

        /// <summary>
        /// Gets the UTC value from string.
        /// </summary>
        /// <param name="x509">The X509Certificate.</param>
        /// <param name="dateTimeValue">The date time value.</param>
        /// <returns></returns>
        public static DateTime GetUtcFromString(this X509Certificate x509, string dateTimeValue)
        {
            return x509.GetLocalFromString(dateTimeValue).ToUniversalTime();
        }

        /// <summary>
        /// Gets the local from string.
        /// </summary>
        /// <param name="x509">The self.</param>
        /// <param name="dateTimeValue">The date time value.</param>
        /// <returns></returns>
        public static DateTime GetLocalFromString(this X509Certificate x509, string dateTimeValue)
        {
            return DateTime.Parse(dateTimeValue);
        }

        /// <summary>
        /// Validates the effectiveness.
        /// </summary>
        /// <param name="x509">The X509Certificate.</param>
        /// <param name="cert">The cert.</param>
        /// <param name="logger">The logger.</param>
        public static void ValidateEffectiveness(this X509Certificate x509, string cert, ILog logger)
        {
            try
            {
                var expires = x509.GetUtcFromString(x509.GetExpirationDateString());

                if ((expires - DateTime.UtcNow).TotalDays < 30)
                {
                    //logger.WarnFormat("The {0} certificate [{1}] is set to expire in less than 30 days on {2}", cert, x509.Subject, expires.ToString("o", CultureInfo.InvariantCulture));
                }
                if ((expires - DateTime.UtcNow).TotalDays <= 0)
                {
                    //logger.ErrorFormat("The {0} certificate [{1}]  has expired on {2}", cert, x509.Subject, expires.ToString("o", CultureInfo.InvariantCulture));
                }
            }
            catch (Exception exception)
            {
                //logger.Error("Unable to make determination of certificate's 'freshness'", exception);
            }

        }
    }
}