public string Decrypt(string value)
{
string res = "";
try
{
if (value == null)
{
return("");
}
if (value.Trim().Length == 0)
{
return("");
}
string encrypted = decrypt_str(value);
encrypted = encrypted.Substring(64);
byte[] encryptedBytesWithSalt = Convert.FromBase64String(encrypted);
byte[] salt = new byte[8];
byte[] encryptedBytes = new byte[encryptedBytesWithSalt.Length - salt.Length - 8];
Buffer.BlockCopy(encryptedBytesWithSalt, 8, salt, 0, salt.Length);
Buffer.BlockCopy(encryptedBytesWithSalt, salt.Length + 8, encryptedBytes, 0, encryptedBytes.Length);
byte[] key, iv;
DeriveKeyAndIV(passphrase, salt, out key, out iv);
res = DecryptStringFromBytesAes(encryptedBytes, key, iv);
}
catch (Exception exp)
{
clsCommon common = new clsCommon();
common.Log("Decrypt", exp.Message + "(value=" + value + ")", true, exp);
}
return(res);
}
public string Decrypt(string encrypted)
{
string res = "";
try
{
if (encrypted == null)
{
return("");
}
if (encrypted.Trim().Length == 0)
{
return("");
}
// base 64 decode
byte[] encryptedBytesWithSalt = Convert.FromBase64String(encrypted);
// extract salt (first 8 bytes of encrypted)
byte[] salt = new byte[8];
byte[] encryptedBytes = new byte[encryptedBytesWithSalt.Length - salt.Length - 8];
Buffer.BlockCopy(encryptedBytesWithSalt, 8, salt, 0, salt.Length);
Buffer.BlockCopy(encryptedBytesWithSalt, salt.Length + 8, encryptedBytes, 0, encryptedBytes.Length);
// get key and iv
byte[] key, iv;
DeriveKeyAndIV(passphrase, salt, out key, out iv);
res = DecryptStringFromBytesAes(encryptedBytes, key, iv);
res = Uri.UnescapeDataString(res);
}
catch (Exception exp)
{
clsCommon common = new clsCommon();
common.Log("Decrypt", exp.Message + "(value=" + encrypted + ")", true, exp);
}
return(res);
}
public bool IsValidString(string val)
{
bool res = false;
try
{
if (val.ToLower().Trim().Contains("'"))
{
return(false);
}
if (val.ToLower().Trim().Contains('"'))
{
return(false);
}
if (val.ToLower().Trim().Contains("&"))
{
return(false);
}
return(true);
}
catch (Exception exp)
{
clsCommon common = new clsCommon();
common.Log("IsValidString", exp.Message + "(val=" + val + ")", true, exp);
}
return(res);
}
public string GetNewPW()
{
string res = "";
try
{
string new_pass = "******";
return(new_pass);
}
catch (Exception exp)
{
clsCommon common = new clsCommon();
common.Log("GetNewPW", exp.Message, true, exp);
}
return(res);
}
public string Encrypt(string plainText)
{
string res = "";
try
{
if (plainText == null)
{
return("");
}
if (plainText.Trim().Length == 0)
{
return("");
}
// generate salt
byte[] key, iv;
byte[] salt = new byte[8];
RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();
rng.GetNonZeroBytes(salt);
DeriveKeyAndIV(passphrase, salt, out key, out iv);
// encrypt bytes
byte[] encryptedBytes = EncryptStringToBytesAes(plainText, key, iv);
// add salt as first 8 bytes
byte[] encryptedBytesWithSalt = new byte[salt.Length + encryptedBytes.Length + 8];
Buffer.BlockCopy(Encoding.ASCII.GetBytes("Salted__"), 0, encryptedBytesWithSalt, 0, 8);
Buffer.BlockCopy(salt, 0, encryptedBytesWithSalt, 8, salt.Length);
Buffer.BlockCopy(encryptedBytes, 0, encryptedBytesWithSalt, salt.Length + 8, encryptedBytes.Length);
// base64 encode
res = Convert.ToBase64String(encryptedBytesWithSalt);
res = Uri.EscapeUriString(res);
}
catch (Exception exp)
{
clsCommon common = new clsCommon();
common.Log("Encrypt", exp.Message + "(value=" + plainText + ")", true, exp);
}
return(res);
}
public string Encrypt(string value)
{
string res = "";
try
{
if (value == null)
{
return("");
}
if (value.Trim().Length == 0)
{
return("");
}
byte[] key, iv;
byte[] salt = new byte[8];
RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();
rng.GetNonZeroBytes(salt);
DeriveKeyAndIV(passphrase, salt, out key, out iv);
byte[] encryptedBytes = EncryptStringToBytesAes(value, key, iv);
byte[] encryptedBytesWithSalt = new byte[salt.Length + encryptedBytes.Length + 8];
Buffer.BlockCopy(Encoding.ASCII.GetBytes("Salted__"), 0, encryptedBytesWithSalt, 0, 8);
Buffer.BlockCopy(salt, 0, encryptedBytesWithSalt, 8, salt.Length);
Buffer.BlockCopy(encryptedBytes, 0, encryptedBytesWithSalt, salt.Length + 8, encryptedBytes.Length);
res = Convert.ToBase64String(encryptedBytesWithSalt);
string new_pass = sha256(passphrase);
string new_enc = CalcHMACSHA256Hash(res, new_pass) + res;
res = encrypt_str(new_enc);
return(res);
}
catch (Exception exp)
{
clsCommon common = new clsCommon();
common.Log("Encrypt", exp.Message + "(value=" + value + ")", true, exp);
}
return(res);
}
