Encryption and Decryption

Question

i want to insert encrypted password into database and check the password from Decrypted password to login login. Pls help me how to check encrypted password with decrypted password from database to login

Ananth G · Answer

Encryption Sometimes we want to encrypt the values that time we use MD5 Encryption and Decryption Here i give the code for Encryption and Decryption. passPhrase ,saltValue ,initVector this variables are the key for Encryption and Decryption public static string passPhrase = "YOUR KEY1"; public static string saltValue = "YOUR KE2"; public static string initVector = "YOUR KE3"; public static string FunForEncrypt(string objText) { int keySize = 256; int passwordIterations = 03; string hashAlgorithm = "MD5"; byte[] initVectorBytes = Encoding.ASCII.GetBytes(initVector); byte[] saltValueBytes = Encoding.ASCII.GetBytes(saltValue); byte[] plainTextBytes = Encoding.UTF8.GetBytes(objText); PasswordDeriveBytes password = new PasswordDeriveBytes ( passPhrase, saltValueBytes, hashAlgorithm, passwordIterations ); byte[] keyBytes = password.GetBytes(keySize / 8); RijndaelManaged symmetricKey = new RijndaelManaged(); symmetricKey.Mode = CipherMode.CBC; ICryptoTransform encryptor = symmetricKey.CreateEncryptor ( keyBytes, initVectorBytes ); MemoryStream memoryStream = new MemoryStream(); CryptoStream cryptoStream = new CryptoStream ( memoryStream, encryptor, CryptoStreamMode.Write ); cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length); cryptoStream.FlushFinalBlock(); byte[] cipherTextBytes = memoryStream.ToArray(); memoryStream.Close(); cryptoStream.Close(); string cipherText = Convert.ToBase64String(cipherTextBytes); cipherText = HttpUtility.UrlEncode(cipherText); return cipherText; } Decryption : this below code used to Decrypt the text public static string FunForDecrypt(string cipherText) { string plainText = ""; int keySize = 256; int passwordIterations = 03; string hashAlgorithm = "MD5"; try { cipherText = HttpUtility.UrlDecode(cipherText); byte[] initVectorBytes = Encoding.ASCII.GetBytes(initVector); byte[] saltValueBytes = Encoding.ASCII.GetBytes(saltValue); byte[] cipherTextBytes = Convert.FromBase64String(cipherText); PasswordDeriveBytes password = new PasswordDeriveBytes ( passPhrase, saltValueBytes, hashAlgorithm, passwordIterations ); byte[] keyBytes = password.GetBytes(keySize / 8); RijndaelManaged symmetricKey = new RijndaelManaged(); symmetricKey.Mode = CipherMode.CBC; ICryptoTransform decryptor = symmetricKey.CreateDecryptor ( keyBytes, initVectorBytes ); MemoryStream memoryStream = new MemoryStream(cipherTextBytes); CryptoStream cryptoStream = new CryptoStream ( memoryStream, decryptor, CryptoStreamMode.Read ); byte[] plainTextBytes = new byte[cipherTextBytes.Length]; int decryptedByteCount = cryptoStream.Read ( plainTextBytes, 0, plainTextBytes.Length ); memoryStream.Close(); cryptoStream.Close(); plainText = Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount); } catch (Exception ex) { plainText = ""; } return plainText; }

Sibeesh Venu · Answer

Hi , You can create those functions as mentioned in this articles. http://www.codeproject.com/Articles/14150/Encrypt-and-Decrypt-Data-with-C http://www.codeproject.com/Articles/5719/Simple-encrypting-and-decrypting-data-in-C Please read those article , you will get complete idea behind encryption and decryption. Please accept as answer if it helped you Kindest Regards Sibeesh http://sibeeshpassion.com/

Sibeesh Venu · Answer

HI Priya, Please see the below links http://www.aspsnippets.com/Articles/Encrypt-and-Decrypt-Username-or-Password-stored-in-database-in-ASPNet-using-C-and-VBNet.aspx http://www.codeproject.com/Questions/304187/how-to-create-password-encrypt-decrypt-in-csharp http://www.codeproject.com/Questions/304187/how-to-create-password-encrypt-decrypt-in-csharp Please accept as answer if it helped you Kindest Regards Sibeesh http://sibeeshpassion.com/

Demir Acar · Answer

What's your lenght of your field ? increase your's field lenght if still continue your's method is wrong .

priya mishra · Answer

Hi, my encryption code is working but at the time of decryption.This gives error : Invalid length for a Base-64 char array or string. My code is public DataSet Add_CheckData() { System.Text.UTF8Encoding encoder = new System.Text.UTF8Encoding(); System.Text.Decoder passDecode = encoder.GetDecoder(); byte[] decodedPassword = Convert.FromBase64String(_Password); int charCount = passDecode.GetCharCount(decodedPassword, 0, decodedPassword.Length); char[] decodedChar = new char[charCount]; passDecode.GetChars(decodedPassword, 0, decodedPassword.Length, decodedChar, 0); string result = new string(decodedChar); SqlParameter[] p = new SqlParameter[] { new SqlParameter("@uname",_UserName), new SqlParameter("@pwd",result) }; return SqlHelper.ExecuteDataset(Obj_con.get_Connection(), CommandType.StoredProcedure, "SP_CheckData", p); } } }

priya mishra · Answer

Is there is any method like convert.ToEncrypt() and Convert.ToDecrypt () to encrypt and decrypt data. Pls tell me i am begineer Thank you

Encryption and Decryption

Answers (6)