encryption Issue

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,

plainTextBytes.Length

);

memoryStream.Close();

cryptoStream.Close();

plainText = Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount);

}

catch (Exception ex)

{

plainText = "";

}

return plainText;

}

3 Replies

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Nitin Sontakke10y ago
Accepted answer
I am not 100% sure, but if you could just try with using just 8 char long encryption key please.
The key used for encryption is not clear in above code.
Just try with a key value which is 8 char long, for example, "Secure01", "Cosmos09", etc.
+3
Ananth G10y ago
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;
}
+1
Midhun Tp10y ago
Hi,
There should be an IV(Initialization Vector) whose size should be 16bytes. Please go through below threads -
http://stackoverflow.com/questions/944833/specified-initialization-vector-iv-does-not-match-the-block-size-for-this-algo
http://stackoverflow.com/questions/6638621/specified-initialization-vector-iv-does-not-match-the-block-size-for-this-algo
http://stackoverflow.com/questions/15019236/specified-initialization-vectoriv-does-not-match-the-block-size-for-this-algor
-3