Best Way For Encryption And Decryption Using C#

In this article, we discuss encryption and decryption using C#. We are using the MD5 algorithm. The MD5 message-digest algorithm is a widely used hash function producing a 128-bit hash value. Although MD5 was initially designed to be used as a cryptographic hash function, it has been found to suffer from extensive vulnerabilities.

MD5 algorithm can still be used as a checksum to verify data integrity, but only against unintentional corruption. It remains suitable for other non-cryptographic purposes, for example for determining the partition for a particular key in a partitioned database. We use the MD5 hash generator as the result is a 128-bit byte array which is a valid length for the TripleDES encoder. We use below to declare the Global Variable.

We write encryption and decryption using the C# method here.


using System;
using System.Net;
using System.Security.Cryptography;
using System.Text;

namespace EncryptionDecryption
{
    public static class UtilityClass
    {
        public static string EncryptString(String toEncrypt, bool useHashing)
        {

            byte[] keyArray;
            byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);

            string key = "SELIM_AHMED_1920";
            if (useHashing)
            {
                MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
                keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
                hashmd5.Clear();
            }
            else
                keyArray = UTF8Encoding.UTF8.GetBytes(key);

            TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
            tdes.Key = keyArray;
            tdes.Mode = CipherMode.ECB;
            tdes.Padding = PaddingMode.PKCS7;

            ICryptoTransform cTransform = tdes.CreateEncryptor();
            byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
            tdes.Clear();
            return Convert.ToBase64String(resultArray, 0, resultArray.Length);
        }
        
        public static string DecryptString(String cipherString, bool useHashing)
        {
            byte[] keyArray;
            byte[] toEncryptArray = Convert.FromBase64String(cipherString);

            string key = "SELIM_AHMED_1920";
            if (useHashing)
            {
                MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
                keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
                hashmd5.Clear();
            }
            else
                keyArray = UTF8Encoding.UTF8.GetBytes(key);

            TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
            tdes.Key = keyArray;
            tdes.Mode = CipherMode.ECB;
            tdes.Padding = PaddingMode.PKCS7;

            ICryptoTransform cTransform = tdes.CreateDecryptor();
            byte[] resultArray = null;
            resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
            tdes.Clear();
            return UTF8Encoding.UTF8.GetString(resultArray);
        }
    }
}

using System;

using System.Net;

using System.Security.Cryptography;

using System.Text;

namespace EncryptionDecryption

{

public static class UtilityClass

{

public static string EncryptString(String toEncrypt, bool useHashing)

{

byte[] keyArray;

byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);

string key = "SELIM_AHMED_1920";

if (useHashing)

{

MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();

keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));

hashmd5.Clear();

}

else

keyArray = UTF8Encoding.UTF8.GetBytes(key);

TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();

tdes.Key = keyArray;

tdes.Mode = CipherMode.ECB;

tdes.Padding = PaddingMode.PKCS7;

ICryptoTransform cTransform = tdes.CreateEncryptor();

byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

tdes.Clear();

return Convert.ToBase64String(resultArray, 0, resultArray.Length);

}

public static string DecryptString(String cipherString, bool useHashing)

{

byte[] keyArray;

byte[] toEncryptArray = Convert.FromBase64String(cipherString);